National Library of Energy BETA

Sample records for grid-connected hydrokinetic tidal

  1. First Commercial, Grid-Connected, Hydrokinetic Tidal Energy Project...

    Office of Science (SC) Website

    First Commercial, Grid-Connected, Hydrokinetic Tidal Energy Project in North America Small Business Innovation Research (SBIR) and Small Business Technology Transfer (STTR) SBIR...

  2. Acoustic Effects of Hydrokinetic Tidal Turbines

    SciTech Connect (OSTI)

    Polagye, Brian

    2011-11-01

    This presentation from the Water Peer Review highlights one of the program's marine and hyrokinetics environmental projects to determine the likely acoustic effects from a tidal energy device.

  3. Maine Deploys First U.S. Commercial, Grid-Connected Tidal Energy...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    of President Obama's all-of-the-above energy strategy to create jobs and strengthen U.S. global competitiveness," said Energy Secretary Steven Chu. "The Eastport tidal energy...

  4. Field Measurements at River and Tidal Current Sites for Hydrokinetic Energy Development: Best Practices Manual

    SciTech Connect (OSTI)

    Neary, Vincent S; Gunawan, Budi

    2011-09-01

    In this report, existing data collection techniques and protocols for characterizing open channel flows are reviewed and refined to further address the needs of the MHK industry. The report provides an overview of the hydrodynamics of river and tidal channels, and the working principles of modern acoustic instrumentation, including best practices in remote sensing methods that can be applied to hydrokinetic energy site characterization. Emphasis is placed upon acoustic Doppler velocimeter (ADV) and acoustic-Doppler current profiler (ADCP) instruments, as these represent the most practical and economical tools for use in the MHK industry. Incorporating the best practices as found in the literature, including the parameters to be measured, the instruments to be deployed, the instrument deployment strategy, and data post-processing techniques. The data collected from this procedure aims to inform the hydro-mechanical design of MHK systems with respect to energy generation and structural loading, as well as provide reference hydrodynamics for environmental impact studies. The standard metrics and protocols defined herein can be utilized to guide field experiments with MHK systems.

  5. GROWDERS Demonstration of Grid Connected Electricity Systems...

    Open Energy Info (EERE)

    GROWDERS Demonstration of Grid Connected Electricity Systems (Smart Grid Project) (Spain) Jump to: navigation, search Project Name GROWDERS Demonstration of Grid Connected...

  6. Assessment and Mapping of the Riverine Hydrokinetic Resource...

    Office of Environmental Management (EM)

    and results of the most rigorous assessment to date of the riverine hydrokinetic energy resource in the contiguous 48 states and Alaska, excluding tidal waters. Assessment...

  7. Assessment and Mapping of the Riverine Hydrokinetic Resource...

    Open Energy Info (EERE)

    riverine hydrokinetic energy resource in the contiguous 48 states and Alaska, excluding tidal waters. The assessment provides estimates of the gross, naturally available...

  8. Environmental Effects of Hydrokinetic Turbines on Fish: Desktop...

    Broader source: Energy.gov (indexed) [DOE]

    provide information to support assessment of the potential for injury and mortality of fish that encounter hydrokinetic turbines of various designs installed in tidal and river...

  9. Integration Technology for PHEV-Grid-Connectivity, with Support...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Technology for PHEV-Grid-Connectivity, with Support for SAE Electrical Standards Integration Technology for PHEV-Grid-Connectivity, with Support for SAE Electrical Standards 2010...

  10. Public Meeting: Physical Characterization of Smart and Grid-Connected...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Smart and Grid-Connected Commercial and Residential Building End-Use Equipment and Appliances Public Meeting: Physical Characterization of Smart and Grid-Connected Commercial and...

  11. Nevada Deploys Grid-Connected Electricity from Enhanced Geothermal...

    Office of Environmental Management (EM)

    Nevada Deploys Grid-Connected Electricity from Enhanced Geothermal Systems Nevada Deploys Grid-Connected Electricity from Enhanced Geothermal Systems May 16, 2013 - 12:00am Addthis...

  12. United States Launches First Grid-Connected Offshore Wind Turbine...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    United States Launches First Grid-Connected Offshore Wind Turbine United States Launches First Grid-Connected Offshore Wind Turbine August 22, 2013 - 12:00am Addthis Leveraging an...

  13. Grid-Connected Renewable Energy Systems | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Grid-Connected Renewable Energy Systems Grid-Connected Renewable Energy Systems July 7, 2015 - 8:21pm Addthis When connecting a home energy system to the electric grid, research...

  14. Marine and Hydrokinetic Technology Database

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    DOE’s Marine and Hydrokinetic Technology Database provides up-to-date information on marine and hydrokinetic renewable energy, both in the U.S. and around the world. The database includes wave, tidal, current, and ocean thermal energy, and contains information on the various energy conversion technologies, companies active in the field, and development of projects in the water. Depending on the needs of the user, the database can present a snapshot of projects in a given region, assess the progress of a certain technology type, or provide a comprehensive view of the entire marine and hydrokinetic energy industry. Results are displayed as a list of technologies, companies, or projects. Data can be filtered by a number of criteria, including country/region, technology type, generation capacity, and technology or project stage. The database was updated in 2009 to include ocean thermal energy technologies, companies, and projects.

  15. Effects of Tidal Turbine Noise on Fish Hearing and Tissues - Draft Final Report - Environmental Effects of Marine and Hydrokinetic Energy

    SciTech Connect (OSTI)

    Halvorsen, Michele B.; Carlson, Thomas J.; Copping, Andrea E.

    2011-09-30

    Snohomish Public Utility District No.1 plans to deploy two 6 meter OpenHydro tidal turbines in Admiralty Inlet in Puget Sound, under a FERC pilot permitting process. Regulators and stakeholders have raised questions about the potential effect of noise from the turbines on marine life. Noise in the aquatic environment is known to be a stressor to many types of aquatic life, including marine mammals, fish and birds. Marine mammals and birds are exceptionally difficult to work with for technical and regulatory reasons. Fish have been used as surrogates for other aquatic organisms as they have similar auditory structures. This project was funded under the FY09 Funding Opportunity Announcement (FOA) to Snohomish PUD, in partnership with the University of Washington - Northwest National Marine Renewable Energy Center, the Sea Mammal Research Unit, and Pacific Northwest National Laboratory. The results of this study will inform the larger research project outcomes. Proposed tidal turbine deployments in coastal waters are likely to propagate noise into nearby waters, potentially causing stress to native organisms. For this set of experiments, juvenile Chinook salmon (Oncorhynchus tshawytscha) were used as the experimental model. Plans exist for prototype tidal turbines to be deployed into their habitat. Noise is known to affect fish in many ways, such as causing a threshold shift in auditory sensitivity or tissue damage. The characteristics of noise, its spectra and level, are important factors that influence the potential for the noise to injure fish. For example, the frequency range of the tidal turbine noise includes the audiogram (frequency range of hearing) of most fish. This study was performed during FY 2011 to determine if noise generated by a 6-m diameter OpenHydro turbine might affect juvenile Chinook salmon hearing or cause barotrauma. Naturally spawning stocks of Chinook salmon that utilize Puget Sound are listed as threatened (http://www.nwr.noaa.gov/ESA-Salmon-Listings/Salmon-Populations/Chinook/CKPUG.cfm); the fish used in this experiment were hatchery raised and their populations are not in danger of depletion. After they were exposed to simulated tidal turbine noise, the hearing of juvenile Chinook salmon was measured and necropsies performed to check for tissue damage. Experimental groups were (1) noise exposed, (2) control (the same handling as treatment fish but without exposure to tidal turbine noise), and (3) baseline (never handled). Experimental results indicate that non-lethal, low levels of tissue damage may have occurred but that there were no effects of noise exposure on the auditory systems of the test fish.

  16. Geothermal/Grid Connection | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View New PagesSustainable UrbanKentucky:Bore TechnologiesAssessment InsettingGrid Connection <

  17. Geothermal/Grid Connection | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource History View New Pages Recent ChangesInformationGeothermal/Grid Connection

  18. United States Launches First Grid-Connected Offshore Wind Turbine...

    Broader source: Energy.gov (indexed) [DOE]

    an EERE investment, the University of Maine deployed the nation's first grid-connected offshore floating wind turbine prototype off the coast of Castine, Maine. The university...

  19. Public Meeting: Physical Characterization of Grid-Connected Commercial...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    (K. Lynn) More Documents & Publications Public Meeting: Physical Characterization of Smart and Grid-Connected Commercial and Residential Building End-Use Equipment and...

  20. Energy Management Problems Under Uncertainties for Grid-Connected Microgrids

    E-Print Network [OSTI]

    Zhang, Wei

    1 Energy Management Problems Under Uncertainties for Grid-Connected Microgrids : a Chance prob- lems under uncertainties for a grid-connected microgrid. The problems are motivated by practical microgrid problems such as peak power shaving and frequency regulation. The problems require constraints

  1. Marine & Hydrokinetic Technologies

    SciTech Connect (OSTI)

    2011-07-01

    This fact sheet describes the Wind and Water Power Program's current approach to supporting the development and deployment of marine and hydrokinetic technologies.

  2. High Penetration, Grid Connected Photovoltaic Technology Codes and Standards: Preprint

    SciTech Connect (OSTI)

    Basso, T. S.

    2008-05-01

    This paper reports the interim status in identifying and reviewing photovoltaic (PV) codes and standards (C&S) and related electrical activities for grid-connected, high-penetration PV systems with a focus on U.S. electric utility distribution grid interconnection.

  3. Submersible Generator for Marine Hydrokinetics

    SciTech Connect (OSTI)

    Robert S. Cinq-Mars; Timothy Burke; Dr. James Irish; Brian Gustafson; Dr. James Kirtley; Dr. Aiman Alawa

    2011-09-01

    A submersible generator was designed as a distinct and critical subassembly of marine hydrokinetics systems, specifically tidal and stream energy conversion. The generator is designed to work with both vertical and horizontal axis turbines. The final product is a high-pole-count, radial-flux, permanent magnet, rim mounted generator, initially rated at twenty kilowatts in a two-meter-per-second flow, and designed to leverage established and simple manufacturing processes. The generator was designed to work with a 3 meter by 7 meter Gorlov Helical Turbine or a marine hydrokinetic version of the FloDesign wind turbine. The team consisted of experienced motor/generator design engineers with cooperation from major US component suppliers (magnetics, coil winding and electrical steel laminations). Support for this effort was provided by Lucid Energy Technologies and FloDesign, Inc. The following tasks were completed: � Identified the conditions and requirements for MHK generators. � Defined a methodology for sizing and rating MHK systems. � Selected an MHK generator topology and form factor. � Completed electromechanical design of submersible generator capable of coupling to multiple turbine styles. � Investigated MHK generator manufacturing requirements. � Reviewed cost implications and financial viability. � Completed final reporting and deliverables

  4. Nevada Deploys First U.S. Commercial, Grid-Connected Enhanced...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Deploys First U.S. Commercial, Grid-Connected Enhanced Geothermal System Nevada Deploys First U.S. Commercial, Grid-Connected Enhanced Geothermal System April 12, 2013 - 12:00pm...

  5. Meeting the New CARB ZEV Mandate Requirements: Grid-Connected Hybrids and City EVs

    E-Print Network [OSTI]

    Burke, Andrew

    2001-01-01

    gov Erin Kassoy Arthur D. Little 10061 Bubb Road Cupertino,15, 2001 Erin Kassoy Arthur D. Little Both Grid Connected

  6. Aalborg Universitet Generation-Side Power Scheduling in a Grid-Connected DC Microgrid

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    Aalborg Universitet Generation-Side Power Scheduling in a Grid-Connected DC Microgrid Hernández). Generation-Side Power Scheduling in a Grid-Connected DC Microgrid. In IEEE ICDCM 2015. IEEE. General rights.aau.dk on: juli 04, 2015 #12;Generation-Side Power Scheduling in a Grid-Connected DC Microgrid Adriana C

  7. Energy dispatch schedule optimization and cost benefit analysis for grid-connected, photovoltaic-battery storage systems

    E-Print Network [OSTI]

    Nottrott, A.; Kleissl, J.; Washom, B.

    2013-01-01

    Grid-connected photovoltaic systems with battery storagesfor grid-connected photovoltaic systems, IEEE Transactionshybrid photovoltaic and battery energy storage system, IEEE

  8. Abrasion Testing of Critical Components of Hydrokinetic Devices

    SciTech Connect (OSTI)

    Worthington, Monty; Ali, Muhammad; Ravens, Tom

    2013-12-06

    The objective of the Abrasion Testing of Critical Components of Hydrokinetic Devices (Project) was to test critical components of hydrokinetic devices in waters with high levels of suspended sediment – information that is widely applicable to the hydrokinetic industry. Tidal and river sites in Alaska typically have high suspended sediment concentrations. High suspended sediment also occurs in major rivers and estuaries throughout the world and throughout high latitude locations where glacial inputs introduce silt into water bodies. In assessing the vulnerability of technology components to sediment induced abrasion, one of the greatest concerns is the impact that the sediment may have on device components such as bearings and seals, failures of which could lead to both efficiency loss and catastrophic system failures.

  9. Assessment of Projected Life-Cycle Costs for Wave, Tidal, Ocean...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Assessment of Projected Life-Cycle Costs for Wave, Tidal, Ocean Current, and In-Stream Hydrokinetic Power Assessment of Projected Life-Cycle Costs for Wave, Tidal, Ocean Current,...

  10. Tidal Energy Research

    SciTech Connect (OSTI)

    Stelzenmuller, Nickolas; Aliseda, Alberto; Palodichuk, Michael; Polagye, Brian; Thomson, James; Chime, Arshiya; Malte, Philip

    2014-03-31

    This technical report contains results on the following topics: 1) Testing and analysis of sub-scale hydro-kinetic turbines in a flume, including the design and fabrication of the instrumented turbines. 2) Field measurements and analysis of the tidal energy resource and at a site in northern Puget Sound, that is being examined for turbine installation. 3) Conceptual design and performance analysis of hydro-kinetic turbines operating at high blockage ratio, for use for power generation and flow control in open channel flows.

  11. DOE Publishes Notice of Public Meeting for Smart Grid-connected...

    Broader source: Energy.gov (indexed) [DOE]

    of the meeting will be: Discuss issues concerning the physical characterization of smart and grid-connected commercial and residential buildings end-use equipment and...

  12. Enviro effects of hydrokinetic turbines on fish | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    effects of hydrokinetic turbines on fish Enviro effects of hydrokinetic turbines on fish Enviro effects of hydrokinetic turbines on fish 47fish-hkturbineinteractionseprijacobs...

  13. Development of New Three-Level Current-Source Inverter for Grid Connected Photovoltaic System

    E-Print Network [OSTI]

    Fujimoto, Hiroshi

    Development of New Three-Level Current-Source Inverter for Grid Connected Photovoltaic System and inverter, and its feasibility on grid connected photovoltaic system application. Using this new topology photovoltaic system 1. INTRODUCTION Solid state inverters allow to put photovoltaic (PV) systems into the power

  14. Aalborg Universitet Control System interaction in the VSC-HVDC Grid Connected Offshore Wind Power

    E-Print Network [OSTI]

    Bak, Claus Leth

    Aalborg Universitet Control System interaction in the VSC-HVDC Grid Connected Offshore Wind Power-HVDC Grid Connected Offshore Wind Power Plant. In Proceedings of the Cigré Symposium 2015. CIGRE. General Offshore Wind Power Plant Jakob Glasdam1,2 , Lukasz Hubert Kocewiak1 , Jesper Hjerrild1 , Claus Leth Bak2 1

  15. Aalborg Universitet Economic Power Dispatch of Distributed Generators in a Grid-Connected Microgrid

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    Aalborg Universitet Economic Power Dispatch of Distributed Generators in a Grid-Connected Microgrid., & Vasquez, J. C. (2015). Economic Power Dispatch of Distributed Generators in a Grid-Connected Microgrid-Connected Microgrid Adriana C. Luna, Nelson L. Diaz, Fabio Andrade, Mois`es Graells§, Josep M. Guerrero, and Juan C

  16. Grid-Connected Marine Current Generation System Power Smoothing Control Using Supercapacitors

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Grid-Connected Marine Current Generation System Power Smoothing Control Using Supercapacitors fluctuations in the generator power. This paper deals with power smoothing control of grid connected MCT system a smoothed grid-injected power in case of swell disturbances. Index Terms-Marine current turbine, power

  17. Power control of a wind farm with active stall wind turbines and AC grid connection

    E-Print Network [OSTI]

    Power control of a wind farm with active stall wind turbines and AC grid connection Anca D. Hansen1 on the wind farm level. The ability of active stall wind farms with AC grid connection to regulate the power, is therefore directed towards optimising the integration of large wind farms within the electrical power grid

  18. Remote performance check and automated failure identification for grid-connected PV systems

    E-Print Network [OSTI]

    Heinemann, Detlev

    Remote performance check and automated failure identification for grid-connected PV systems cloudy skies. This determines the quality of the PV simulation and finally the period of time, satellite data, PVSAT-2 1. Introduction Failure-free operation of grid-connected photovoltaic (PV) systems

  19. Storage Size Determination for Grid-Connected Photovoltaic Systems

    E-Print Network [OSTI]

    Ru, Yu; Martinez, Sonia

    2011-01-01

    In this paper, we study the problem of determining the size of battery storage used in grid-connected photovoltaic (PV) systems. In our setting, electricity is generated from PV and is used to supply the demand from loads. Excess electricity generated from the PV can be stored in a battery to be used later on, and electricity must be purchased from the electric grid if the PV generation and battery discharging cannot meet the demand. The objective is to minimize the electricity purchase from the electric grid while at the same time choosing an appropriate battery size. More specifically, we want to find a unique critical value (denoted as $E_{max}^c$) of the battery size such that the cost of electricity purchase remains the same if the battery size is larger than or equal to $E_{max}^c$, and the cost is strictly larger if the battery size is smaller than $E_{max}^c$. We propose an upper bound on $E_{max}^c$, and show that the upper bound is achievable for certain scenarios. For the case with ideal PV generat...

  20. OCEANS`13 MTS/IEEE SAN DIEGO, SEPTEMBER 2013 1 Electromechanical Emulation of Hydrokinetic

    E-Print Network [OSTI]

    Siefert, Chris

    interesting due to the high power density of river and tidal water currents as well as ocean waves that have Abstract--The pace of research and development efforts to integrate renewable power sources into modern paramount. In particular, hydrokinetic power is appealing due to its high energy density and superior

  1. Lifetime-dependent Battery Usage Optimization for Grid-Connected Residential Systems

    E-Print Network [OSTI]

    Simunic, Tajana

    utility energy prices. Our approach enables us determine the true operational cost and lifetimeLifetime-dependent Battery Usage Optimization for Grid-Connected Residential Systems Jagannathan Venkatesh# , Shengbo Chen* , Peerapol Tinnakornsrisuphap*, Tajana Simunic Rosing# # University of California

  2. An economic analysis of grid-connected residential solar photovoltaic power systems

    E-Print Network [OSTI]

    Carpenter, Paul R.

    The question of the utility grid-connected residential market for photovoltaics is examined from a user-ownership perspective. The price is calculated at which the user would be economically indifferent between

  3. QUALIFIED FORECAST OF ENSEMBLE POWER PRODUCTION BY SPATIALLY DISPERSED GRID-CONNECTED PV SYSTEMS

    E-Print Network [OSTI]

    Heinemann, Detlev

    , Energy Meteorology Group, D-26111 Oldenburg, Germany, elke.lorenz@uni-oldenburg.de + UniversityQUALIFIED FORECAST OF ENSEMBLE POWER PRODUCTION BY SPATIALLY DISPERSED GRID- CONNECTED PV SYSTEMS Schneider° * University of Oldenburg, Institute of Physics, Energy and Semiconductor Research Laboratory

  4. Maine Deploys First U.S. Commercial, Grid-Connected Tidal Energy Project |

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACTThousandReport) |AdministrationStanfordLabMailCharles Hanley

  5. Marine and Hydrokinetic Technology (MHK) Instrumentation, Measurement...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Technology (MHK) Instrumentation, Measurement, and Computer Modeling Workshop Marine and Hydrokinetic Technology (MHK) Instrumentation, Measurement, and Computer Modeling Workshop...

  6. New Report States That Hydrokinetic Turbines Have Minimal Environmenta...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    New Report States That Hydrokinetic Turbines Have Minimal Environmental Impacts on Fish New Report States That Hydrokinetic Turbines Have Minimal Environmental Impacts on Fish...

  7. Environmental Effects of Hydrokinetic Turbines on Fish: Desktop...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Environmental Effects of Hydrokinetic Turbines on Fish: Desktop and Laboratory Flume Studies Environmental Effects of Hydrokinetic Turbines on Fish: Desktop and Laboratory Flume...

  8. Proceedings of the Hydrokinetic and Wave Energy Technologies...

    Office of Environmental Management (EM)

    Proceedings of the Hydrokinetic and Wave Energy Technologies Technical and Environmental Issues Workshop Proceedings of the Hydrokinetic and Wave Energy Technologies Technical and...

  9. Assessment and Mapping of the Riverine Hydrokinetic Resource...

    Broader source: Energy.gov (indexed) [DOE]

    Assessment and Mapping of the Riverine Hydrokinetic Resource in the Continental United States Marine and Hydrokinetic Energy Projects Water Power for a Clean Energy Future...

  10. Request for Information Regarding the Testing of Marine and Hydrokinet...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Request for Information Regarding the Testing of Marine and Hydrokinetic Systems Request for Information Regarding the Testing of Marine and Hydrokinetic Systems January 14, 2015 -...

  11. Potential Impacts of Hydrokinetic and Wave Energy Conversion...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Potential Impacts of Hydrokinetic and Wave Energy Conversion Technologies on Aquatic Environments Potential Impacts of Hydrokinetic and Wave Energy Conversion Technologies on...

  12. Effects of Tidal Turbine Noise on Fish Task 2.1.3.2: Effects on Aquatic Organisms: Acoustics/Noise - Fiscal Year 2011 - Progress Report - Environmental Effects of Marine and Hydrokinetic Energy

    SciTech Connect (OSTI)

    Halvorsen, Michele B.; Carlson, Thomas J.; Copping, Andrea E.

    2011-09-30

    Naturally spawning stocks of Chinook salmon (Oncorhynchus tshawytscha) that utilize Puget Sound are listed as threatened (http://www.nwr.noaa.gov/ESA-Salmon-Listings/Salmon-Populations/ Chinook/CKPUG.cfm). Plans exist for prototype tidal turbines to be deployed into their habitat. Noise is known to affect fish in many ways, such as causing a threshold shift in auditory sensitivity or tissue damage. The characteristics of noise, its spectra and level, are important factors that influence the potential for the noise to injure fish. For example, the frequency range of the tidal turbine noise includes the audiogram (frequency range of hearing) of most fish. This study (Effects on Aquatic Organisms, Subtask 2.1.3.2: Acoustics) was performed during FY 2011 to determine if noise generated by a 6-m-diameter open-hydro turbine might affect juvenile Chinook salmon hearing or cause barotrauma. After they were exposed to simulated tidal turbine noise, the hearing of juvenile Chinook salmon was measured and necropsies performed to check for tissue damage. Experimental groups were (1) noise exposed, (2) control (the same handling as treatment fish but without exposure to tidal turbine noise), and (3) baseline (never handled). Preliminary results indicate that low levels of tissue damage may have occurred but that there were no effects of noise exposure on the auditory systems of the test fish.

  13. Reactive power control of grid-connected wind farm based on adaptive dynamic programming

    E-Print Network [OSTI]

    He, Haibo

    Reactive power control of grid-connected wind farm based on adaptive dynamic programming Yufei Tang and integration with the grid. This controller can effectively dampen the oscillation of the wind farm system under grid fault. In general, there are mainly three kinds of wind power generators: squirrel

  14. Modeling and Grid impedance Variation Analysis of Parallel Connected Grid Connected Inverter

    E-Print Network [OSTI]

    Bak, Claus Leth

    of power converter are important issues todays as the grid is becoming much more power electronics filtering and resonance damping methods are studied in islanded micro- grid application to reduceModeling and Grid impedance Variation Analysis of Parallel Connected Grid Connected Inverter based

  15. Environmental impacts of large-scale grid-connected ground-mounted PV installations

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Environmental impacts of large-scale grid-connected ground-mounted PV installations Antoine Beylota-scale ground-mounted PV installations by considering a life-cycle approach. The methodology is based. Mobile PV installations with dual-axis trackers show the largest impact potential on ecosystem quality

  16. Power Smoothing Control in a Grid-Connected Marine Current Turbine System for Compensating

    E-Print Network [OSTI]

    Boyer, Edmond

    Power Smoothing Control in a Grid-Connected Marine Current Turbine System for Compensating Swell speed may lead to strong fluctuations in the power extracted by a marine current turbine (MCT). During disturbances. Index Terms--Marine current turbine, power fluctuation, swell effect, power smoothing control

  17. FAILURE DETECTION ROUTINE FOR GRID CONNECTED PV SYSTEMS AS PART OF THE PVSAT-2 PROJECT

    E-Print Network [OSTI]

    Heinemann, Detlev

    FAILURE DETECTION ROUTINE FOR GRID CONNECTED PV SYSTEMS AS PART OF THE PVSAT-2 PROJECT S. Stettler1.stettler@enecolo.ch, tel. +41 44 994 9001, fax. +41 44 994 9005 ABSTRACT: Identification of energy losses in PV systems up automatically analysing the performance of PV systems and, in case of a malfunction, determining possible causes

  18. Utility Grid-Connected Distributed Power Systems National Solar Energy Conference

    E-Print Network [OSTI]

    capacity and energy benefits. The Solar Buildings Program provides design assistance and incentivesUtility Grid-Connected Distributed Power Systems National Solar Energy Conference ASES Solar 96-effective in these applications by about the year 2000. In the first three years, SMUD has installed over 340 residential

  19. 564 IEEE JOURNAL OF PHOTOVOLTAICS, VOL. 2, NO. 4, OCTOBER 2012 Dynamic Stability of Three-Phase Grid-Connected

    E-Print Network [OSTI]

    Pota, Himanshu Roy

    564 IEEE JOURNAL OF PHOTOVOLTAICS, VOL. 2, NO. 4, OCTOBER 2012 Dynamic Stability of Three-Phase Grid-Connected Photovoltaic System Using Zero Dynamic Design Approach M. A. Mahmud, Student Member of the dynamic response of a three-phase grid-connected photovoltaic (PV) system. To control the grid cur- rent

  20. Sandia Energy - Marine Hydrokinetics Technology: Market Acceleration

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    on aquatic organisms, with early emphasis on the effects of electromagnetic fields (EMF), acoustic noise from currenttidal, wave and riverine hydrokinetic generators, toxicity...

  1. Energy 101: Marine and Hydrokinetic Energy

    ScienceCinema (OSTI)

    None

    2014-06-26

    See how marine and hydrokinetic technologies harness the energy of the ocean's waves, tides, and currents and convert it into electricity to power our homes, buildings and cities.

  2. Marine and Hydrokinetic Technologies Fact Sheet

    Office of Energy Efficiency and Renewable Energy (EERE)

    This fact sheet describes the Wind and Water Power Program's current approach to supporting the development and deployment of marine and hydrokinetic technologies.

  3. Energy 101: Marine and Hydrokinetic Energy

    SciTech Connect (OSTI)

    2013-04-29

    See how marine and hydrokinetic technologies harness the energy of the ocean's waves, tides, and currents and convert it into electricity to power our homes, buildings and cities.

  4. Sandia Energy - Investigations on Marine Hydrokinetic Turbine...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Marine Hydrokinetic Turbine Foil Structural Health Monitoring Presented at GMREC METS Home Renewable Energy Energy Water Power News News & Events Systems Analysis Investigations on...

  5. Energy dispatch schedule optimization and cost benefit analysis for grid-connected, photovoltaic-battery storage systems

    E-Print Network [OSTI]

    Nottrott, A.; Kleissl, J.; Washom, B.

    2013-01-01

    G. Corey, Energy Storage for the Electricity Grid: Benefitsthe energy storage dispatch schedule for a grid-connected,energy storage technologies as a means to integrate renewable energy resources into electric grids

  6. July 11 Public Meeting: Physical Characterization of Grid-Connected Commercial And Residential Building End-Use Equipment And Appliances

    Broader source: Energy.gov [DOE]

    These documents contain the three slide decks presented at the public meeting on the Physical Characterization of Grid-Connected Commercial and Residential Buildings End-Use Equipment and Appliances, held on July 11, 2014 in Washington, DC.

  7. Simulating Collisions for Hydrokinetic Turbines

    SciTech Connect (OSTI)

    Richmond, Marshall C.; Romero Gomez, Pedro DJ; Rakowski, Cynthia L.

    2013-10-01

    Evaluations of blade-strike on an axial-flow Marine Hydrokinetic turbine were conducted using a conventional methodology as well as an alternative modeling approach proposed in the present document. The proposed methodology integrates the following components into a Computa- tional Fluid Dynamics (CFD) model: (i) advanced eddy-resolving flow simulations, (ii) ambient turbulence based on field data, (iii) moving turbine blades in highly transient flows, and (iv) Lagrangian particles to mimic the potential fish pathways. The sensitivity of blade-strike prob- ability to the following conditions was also evaluated: (i) to the turbulent environment, (ii) to fish size and (iii) to mean stream flow velocity. The proposed methodology provided fraction of collisions and offered the capability of analyzing the causal relationships between the flow envi- ronment and resulting strikes on rotating blades. Overall, the conventional methodology largely overestimates the probability of strike, and lacks the ability to produce potential fish and aquatic biota trajectories as they interact with the rotating turbine. By using a set of experimental corre- lations of exposure-response of living fish colliding on moving blades, the occurrence, frequency and intensity of the particle collisions was next used to calculate the survival rate of fish crossing the MHK turbine. This step indicated survival rates always greater than 98%. Although the proposed CFD framework is computationally more expensive, it provides the advantage of evaluating multiple mechanisms of stress and injury of hydrokinetic turbine devices on fish.

  8. Marine and Hydrokinetic Energy Projects, Fiscal Years 2008-2014

    SciTech Connect (OSTI)

    2014-03-24

    This report covers the Wind and Water Power Technologies Office's Marine and Hydrokinetic Energy Projects from 2008 to 2014.

  9. Smart Energy Management and Control for Fuel Cell Based Micro-Grid Connected Neighborhoods

    SciTech Connect (OSTI)

    Dr. Mohammad S. Alam

    2006-03-15

    Fuel cell power generation promises to be an efficient, pollution-free, reliable power source in both large scale and small scale, remote applications. DOE formed the Solid State Energy Conversion Alliance with the intention of breaking one of the last barriers remaining for cost effective fuel cell power generation. The Alliance’s goal is to produce a core solid-state fuel cell module at a cost of no more than $400 per kilowatt and ready for commercial application by 2010. With their inherently high, 60-70% conversion efficiencies, significantly reduced carbon dioxide emissions, and negligible emissions of other pollutants, fuel cells will be the obvious choice for a broad variety of commercial and residential applications when their cost effectiveness is improved. In a research program funded by the Department of Energy, the research team has been investigating smart fuel cell-operated residential micro-grid communities. This research has focused on using smart control systems in conjunction with fuel cell power plants, with the goal to reduce energy consumption, reduce demand peaks and still meet the energy requirements of any household in a micro-grid community environment. In Phases I and II, a SEMaC was developed and extended to a micro-grid community. In addition, an optimal configuration was determined for a single fuel cell power plant supplying power to a ten-home micro-grid community. In Phase III, the plan is to expand this work to fuel cell based micro-grid connected neighborhoods (mini-grid). The economic implications of hydrogen cogeneration will be investigated. These efforts are consistent with DOE’s mission to decentralize domestic electric power generation and to accelerate the onset of the hydrogen economy. A major challenge facing the routine implementation and use of a fuel cell based mini-grid is the varying electrical demand of the individual micro-grids, and, therefore, analyzing these issues is vital. Efforts are needed to determine the most appropriate means of implementing micro-grids and the costs and processes involved with their extended operation. With the development and availability of fuel cell based stand-alone power plants, an electrical mini-grid, encompassing several connected residential neighborhoods, has become a viable concept. A primary objective of this project is to define the parameters of an economically efficient fuel cell based mini-grid. Since pure hydrogen is not economically available in sufficient quantities at the present time, the use of reforming technology to produce and store excess hydrogen will also be investigated. From a broader perspective, the factors that bear upon the feasibility of fuel cell based micro-grid connected neighborhoods are similar to those pertaining to the electrification of a small town with a localized power generating station containing several conventional generating units. In the conventional case, the town or locality would also be connected to the larger grid system of the utility company. Therefore, in the case of the fuel cell based micro-grid connected neighborhoods, this option should also be available. The objectives of this research project are: To demonstrate that smart energy management of a fuel cell based micro-grid connected neighborhood can be efficient and cost-effective;To define the most economical micro-grid configuration; and, To determine how residential micro-grid connected fuel cell(s) can contribute to America's hydrogen energy future.

  10. Assessing the Effects of Marine and Hydrokinetic Energy Development on Marine and Estuarine Resources

    SciTech Connect (OSTI)

    Ward, Jeffrey A.; Schultz, Irvin R.; Woodruff, Dana L.; Roesijadi, Guritno; Copping, Andrea E.

    2010-07-30

    The world’s oceans and estuaries offer an enormous potential to meet the nation’s growing demand for energy. The use of marine and hydrokinetic (MHK) devices to harness the power of wave and tidal energy could contribute significantly toward meeting federal- and state-mandated renewable energy goals while supplying a substantial amount of clean energy to coastal communities. Locations along the eastern and western coasts of the United States between 40° and 70° north latitude are ideal for MHK deployment, and recent estimates of energy potential for the coasts of Washington, Oregon, and California suggest that up to 25 gigawatts could be generated from wave and tidal devices in these areas. Because energy derived from wave and tidal devices is highly predictable, their inclusion in our energy portfolio could help balance available sources of energy production, including hydroelectric, coal, nuclear, wind, solar, geothermal, and others.

  11. Agenda for Public Meeting on the Physical Characterization of Grid-Connected Commercial and Residential Buildings End-Use Equipment and Appliances

    Broader source: Energy.gov [DOE]

    Download the agenda below for the July 11 Public Meeting on the Physical Characterization of Grid-Connected Commercial and  Residential Buildings End-Use Equipment and Appliances.

  12. Maine Tidal Power Initiative: Environmental Impact Protocols For Tidal Power

    SciTech Connect (OSTI)

    Peterson, Michael Leroy; Zydlewski, Gayle Barbin; Xue, Huijie; Johnson, Teresa R.

    2014-02-02

    The Maine Tidal Power Initiative (MTPI), an interdisciplinary group of engineers, biologists, oceanographers, and social scientists, has been conducting research to evaluate tidal energy resources and better understand the potential effects and impacts of marine hydro-kinetic (MHK) development on the environment and local community. Project efforts include: 1) resource assessment, 2) development of initial device design parameters using scale model tests, 3) baseline environmental studies and monitoring, and 4) human and community responses. This work included in-situ measurement of the environmental and social response to the pre-commercial Turbine Generator Unit (TGU®) developed by Ocean Renewable Power Company (ORPC) as well as considering the path forward for smaller community scale projects.

  13. MHK Projects/Piscataqua Tidal Hydrokinetic Energy Project | Open Energy

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas:Montezuma,Information MHKMHK5 < MHK ProjectsHawaiiInformationIsland

  14. Environmental Effects of Hydrokinetic Turbines on Fish: Desktop and Laboratory Flume Studies

    SciTech Connect (OSTI)

    Jacobson, Paul T.; Amaral, Stephen V.; Castro-Santos, Theodore; Giza, Dan; Haro, Alexander J.; Hecker, George; McMahon, Brian; Perkins, Norman; Pioppi, Nick

    2012-12-31

    This collection of three reports describes desktop and laboratory flume studies that provide information to support assessment of the potential for injury and mortality of fish that encounter hydrokinetic turbines of various designs installed in tidal and river environments. Behavioral responses to turbine exposure also are investigated to support assessment of the potential for disruptions to upstream and downstream movements of fish. The studies: (1) conducted an assessment of potential injury mechanisms using available data from studies with conventional hydro turbines; (2) developed theoretical models for predicting blade strike probabilities and mortality rates; and (3) performed flume testing with three turbine designs and several fish species and size groups in two laboratory flumes to estimate survival rates and document fish behavior. The project yielded three reports which this document comprises. The three constituent documents are addressed individually below Fish Passage Through Turbines: Application of Conventional Hydropower Data to Hydrokinetic Technologies Fish passing through the blade sweep of a hydrokinetic turbine experience a much less harsh physical environment than do fish entrained through conventional hydro turbines. The design and operation of conventional turbines results in high flow velocities, abrupt changes in flow direction, relatively high runner rotational and blade speeds, rapid and significant changes in pressure, and the need for various structures throughout the turbine passageway that can be impacted by fish. These conditions generally do not occur or are not significant factors for hydrokinetic turbines. Furthermore, compared to conventional hydro turbines, hydrokinetic turbines typically produce relatively minor changes in shear, turbulence, and pressure levels from ambient conditions in the surrounding environment. Injuries and mortality from mechanical injuries will be less as well, mainly due to low rotational speeds and strike velocities, and an absence of structures that can lead to grinding or abrasion injuries. Additional information is needed to rigorously assess the nature and magnitude of effects on individuals and populations, and to refine criteria for design of more fish-friendly hydrokinetic turbines. Evaluation of Fish Injury and Mortality Associated with Hydrokinetic Turbines Flume studies exposed fish to two hydrokinetic turbine designs to determine injury and survival rates and to assess behavioral responses. Also, a theoretical model developed for predicting strike probability and mortality of fish passing through conventional hydro turbines was adapted for use with hydrokinetic turbines and applied to the two designs evaluated during flume studies. The flume tests were conducted with the Lucid spherical turbine (LST), a Darrieus-type (cross flow) turbine, and the Welka UPG, an axial flow propeller turbine. Survival rates for rainbow trout tested with the LST were greater than 98% for both size groups and approach velocities evaluated. Turbine passage survival rates for rainbow trout and largemouth bass tested with the Welka UPG were greater than 99% for both size groups and velocities evaluated. Injury rates of turbine-exposed fish were low with both turbines and generally comparable to control fish. Video observations of the LST demonstrated active avoidance of turbine passage by a large proportion fish despite being released about 25 cm upstream of the turbine blade sweep. Video observations from behavior trials indicated few if any fish pass through the turbines when released farther upstream. The theoretical predictions for the LST indicated that strike mortality would begin to occur at an ambient current velocity of about 1.7 m/s for fish with lengths greater than the thickness of the leading edge of the blades. As current velocities increase above 1.7 m/s, survival was predicted to decrease for fish passing through the LST, but generally remained high (greater than 90%) for fish less than 200 mm in length. Strike mortality was not predicted to occur duri

  15. US Department of Energy (DOE) National Lab Activities in Marine Hydrokinetics: Scaled Model

    E-Print Network [OSTI]

    Siefert, Chris

    US Department of Energy (DOE) National Lab Activities in Marine Hydrokinetics: Scaled Model Testing turbines specifically designed by the US Department of Energy for its Marine and Hydrokinetic Research. Keywords-- current energy conversion, performance testing, reference models, marine hydrokinetic

  16. Understanding the Benefits of Dispersed Grid-Connected Photovoltaics: From Avoiding the Next Major Outage to Taming Wholesale Power Markets

    SciTech Connect (OSTI)

    Letendre, Steven E.; Perez, Richard

    2006-07-15

    Thanks to new solar resource assessment techniques using cloud cover data available from geostationary satellites, it is apparent that grid-connected PV installations can serve to enhance electric grid reliability, preventing or hastening recovery from major power outages and serving to mitigate extreme price spikes in wholesale energy markets. (author)

  17. Monitoring and analysis of two grid connected PV systems Michael BRESSAN* Valrie DUPE**, Bruno JAMMES**, Thierry TALBERT*, Corinne ALONSO**

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Monitoring and analysis of two grid connected PV systems Michael BRESSAN* Valérie DUPE**, Bruno, avenue du Colonel Roche 66100, Perpignan, France BP 54200 31031 Toulouse cedex 4 5.2 PV System and monitored for fault detection ad predictive reliability. The first PV grid, is at CNRS-PROMES laboratory

  18. OFF-SHORE WIND AND GRID-CONNECTED PV: HIGH PENETRATION PEAK SHAVING FOR NEW YORK CITY

    E-Print Network [OSTI]

    Perez, Richard R.

    OFF-SHORE WIND AND GRID-CONNECTED PV: HIGH PENETRATION PEAK SHAVING FOR NEW YORK CITY Richard Perez-shore wind and PV generation using the city of New York as a test case. While wind generation is not known one year's worth of hourly site & time-specific data including electrical demand PV and off-shore wind

  19. Utility Scale Wind Turbines on a Grid Connected Island Mohit Dua, Anthony L. Rogers, James F. Manwell,

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    Utility Scale Wind Turbines on a Grid Connected Island Mohit Dua, Anthony L. Rogers, James F utility scale wind turbines on Fox Islands, located 12 miles from the coast of Maine in the United States of electricity itself. Three locations are analyzed in detail as potential sites for wind turbine installations

  20. FORECAST OF ENSEMBLE POWER PRODUCTION BY GRID-CONNECTED PV SYSTEMS Elke Lorenz*, Detlev Heinemann*, Hashini Wickramarathne*, Hans Georg Beyer +

    E-Print Network [OSTI]

    Heinemann, Detlev

    of Physics, Energy and Semiconductor Research Laboratory, Energy Meteorology Group, 26111 Oldenburg, GermanyH, Spicherer Straße 48, D-86157 Augsburg, Germany ABSTRACT: The contribution of power production by PV systemsFORECAST OF ENSEMBLE POWER PRODUCTION BY GRID-CONNECTED PV SYSTEMS Elke Lorenz*, Detlev Heinemann

  1. Electricity storage for grid-connected household dwellings with PV panels

    SciTech Connect (OSTI)

    Mulder, Grietus; Six, Daan; Ridder, Fjo De

    2010-07-15

    Classically electricity storage for PV panels is mostly designed for stand-alone applications. In contrast, we focus in this article on houses connected to the grid with a small-scale storage to store a part of the solar power for postponed consumption within the day or the next days. In this way the house owner becomes less dependent on the grid and does only pay for the net shortage of his energy production. Local storage solutions pave the way for many new applications like omitting over-voltage of the line and bridging periods of power-line black-out. Since 2009 using self-consumption of PV energy is publicly encouraged in Germany, which can be realised by electric storage. This paper develops methods to determine the optimal storage size for grid-connected dwellings with PV panels. From measurements in houses we were able to establish calculation rules for sizing the storage. Two situations for electricity storage are covered: - the storage system is an optimum to cover most of the electricity needs; - it is an optimum for covering the peak power need of a dwelling. After these calculation rules a second step is needed to determine the size of the real battery. The article treats the aspects that should be taken into consideration before buying a specific battery like lead-acid and lithium-ion batteries. (author)

  2. ORNL/TM-2011/419 Field Measurements at River and Tidal

    E-Print Network [OSTI]

    Siefert, Chris

    National Laboratory 3 Northwest National Marine Renewable Energy Center, University of Washington 4 IIHRORNL/TM-2011/419 Field Measurements at River and Tidal Current Sites for Hydrokinetic Energy Reports produced after January 1, 1996, are generally available free via the U.S. Department of Energy

  3. Environmental Effects of Hydrokinetic Turbines on Fish: Desktop...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Environmental Effects of Hydrokinetic Turbines on Fish: Desktop and Laboratory Flume Studies 2012 Project Manager: Paul T. Jacobson 1 Principal Investigators: Stephen V. Amaral 2...

  4. Sandia Energy - Biofouling Studies on Sandia's Marine Hydrokinetic...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    News News & Events Systems Analysis Materials Science Biofouling Studies on Sandia's Marine Hydrokinetic Coatings Initiated at PNNL's Sequim Bay Previous Next Biofouling Studies...

  5. Upcoming Funding Opportunity for Marine and Hydrokinetic Development...

    Broader source: Energy.gov (indexed) [DOE]

    of Energy (DOE) announced a Notice of Intent to issue a funding opportunity titled "Marine and Hydrokinetic (MHK) Research and Development University Consortium." The goal of...

  6. Funding Opportunity Announcement for a Marine and Hydrokinetic...

    Broader source: Energy.gov (indexed) [DOE]

    the U.S. Department of Energy (DOE) announced a 4 million funding opportunity titled "Marine and Hydrokinetic Development University Consortium." This funding opportunity is...

  7. Sandia Energy - Biofouling Studies on Sandia's Marine Hydrokinetic...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energy Water Power Partnership News News & Events Biofouling Studies on Sandia's Marine Hydrokinetic (MHK) Coatings Initiated at PNNL's Sequim Bay Previous Next Biofouling...

  8. Upcoming Funding Opportunity for Competitive Marine and Hydrokinetic...

    Broader source: Energy.gov (indexed) [DOE]

    Competitive Marine and Hydrokinetic (MHK) Demonstrations at the Navy's Wave Energy Test Site (WETS)." The goal of this funding opportunity is to collect important performance and...

  9. Request for Information for Marine and Hydrokinetic Environmental...

    Broader source: Energy.gov (indexed) [DOE]

    Water Power Program is seeking feedback from the marine and hydrokinetic (MHK) industry, academia, research laboratories, government agencies, and other stakeholders regarding the...

  10. Funding Opportunity Announcement for a Marine and Hydrokinetic...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Announces 7.25 Million for Projects to Advance America's Emerging Marine & Hydrokinetic Industry Energy Department Announces 10 Million for Full-Scale Wave Energy Device Testing...

  11. 2014-04-30 Public Meeting Agenda: Physical Characterization of Smart and Grid-Connected Commercial and Residential Buildings End-Use Equipment and Appliances

    Broader source: Energy.gov [DOE]

    This document is the agenda for the Physical Characterization of Smart and Grid-Connected Commercial and Residential Buildings End-Use Equipment and Appliances public meeting being held on April 30, 2014.

  12. 2014-04-30 Public Meeting Presentation Slides: Physical Characterization of Smart and Grid-Connected Commercial and Residential Buildings End-Use Equipment and Appliances

    Broader source: Energy.gov [DOE]

    These documents contain slide decks presented at the Physical Characterization of Smart and Grid-Connected Commercial and Residential Buildings End-Use Equipment and Appliances public meeting held on April 30, 2014.

  13. Compatibility Study of Protective Relaying in a Grid-Connected Fuel Cell

    SciTech Connect (OSTI)

    Staunton, R.H.

    2004-04-15

    A 200-kW fuel cell produced by International Fuel Cells (IFC), a United Technologies Company, began operation at the National Transportation Research Center (NTRC) in early June 2003. The NTRC is a joint Oak Ridge National laboratory (ORNL) and University of Tennessee research facility located in Knoxville, Tennessee. This research activity investigated the protective relaying functions of this fully commercialized fuel cell power plant, which uses ''synthesized'' protective relays. The project's goal is to characterize the compatibility between the fuel cell's interconnection protection system and the local distribution system or electric power system (EPS). ORNL, with assistance from the Electric Power Research Institute-Power Electronics Applications Center (EPRI-PEAC) in Knoxville, Tennessee, monitored and characterized the system compatibility over a period of 6 months. Distribution utility engineers are distrustful of or simply uncomfortable with the protective relaying and hardware provided as part of distributed generation (DG) plants. Part of this mistrust is due to the fact that utilities generally rely on hardware from certain manufacturers whose reliability is well established based on performance over many years or even decades. Another source of concern is the fact that fuel cells and other types of DG do not use conventional relays but, instead, the protective functions of conventional relays are simulated by digital circuits in the distributed generator's grid interface control unit. Furthermore, the testing and validation of internal protection circuits of DG are difficult to accomplish and can be changed by the vendor at any time. This study investigated and documented the safety and protective relaying present in the IFC fuel cell, collected data on the operation of the fuel cell, recorded event data during EPS disturbances, and assessed the compatibility of the synthesized protective circuits and the local distribution system. The project also addressed other important and timely issues. For instance, the study includes an evaluation of the effectiveness of the fuel cell's synthesized relay protection scheme relative to the recently issued IEEE 1547 interconnection standard. Together, these activities should serve to reduce the number of unknowns pertaining to unconventional protective circuits, to the benefit of DG manufacturers, vendors, prospective and current users of DG, and electricity suppliers/distributors. Although more grid-connect fuel cell interruptions were encountered in this study than originally anticipated, and the investigation and findings became quite complex, every effort was made to clearly summarize the interconnection causes and issues throughout the report and especially in the summary found in Sect. 4. ORNL's funding of this study is sponsored equally by (1) the Department of Energy's (DOE's) Office of Distributed Energy Resources and (2) the Distributed Generation Technologies program of the Tennessee Valley Authority (TVA).

  14. Evaluating Effects of Stressors from Marine and Hydrokinetic Energy

    SciTech Connect (OSTI)

    Copping, Andrea E.; Blake, Kara M.; Hanna, Luke A.; Brandt, Charles A.; Ward, Jeffrey A.; Brandenberger, Jill M.; Gill, Gary A.; Carlson, Thomas J.; Elster, Jennifer L.; Jones, Mark E.; Watson, Bruce E.; Jepsen, Richard A.; Metzinger, Kurt

    2012-09-30

    Potential environmental effects of marine and hydrokinetic (MHK) energy development are not well understood, yet regulatory agencies are required to make decisions in spite of substantial uncertainty about environmental impacts and their long-term consequences. An understanding of risks associated with interactions between MHK installations and aquatic receptors, including animals, habitats, and ecosystems, can help define key uncertainties and focus regulatory actions and scientific studies on interactions of most concern. During FY 2012, Pacific Northwest National Laboratory (PNNL) continued to follow project developments on the two marine and hydrokinetic projects reviewed for Environmental Risk Evaluation System (ERES) screening analysis in FY 2011: a tidal project in the Gulf of Maine using Ocean Renewable Power Company TidGenTM turbines and a wave project planned for the coast of Oregon using Aquamarine Oyster surge devices. The ERES project in FY 2012 also examined two stressor–receptor interactions previously identified through the screening process as being of high importance: 1) the toxicity effects of antifouling coatings on MHK devices on aquatic resources and 2) the risk of a physical strike encounter between an adult killer whale and an OpenHydro turbine blade. The screening-level assessment of antifouling paints and coatings was conducted for two case studies: the Snohomish County Public Utility District No. 1 (SnoPUD) tidal turbine energy project in Admiralty Inlet, Puget Sound, Washington, and the Ocean Power Technologies (OPT) wave buoy project in Reedsport, Oregon. Results suggest minimal risk to aquatic biota from antifouling coatings used on MHK devices deployed in large estuaries or open ocean environments. For the strike assessment of a Southern Resident Killer Whale (SRKW) encountering an OpenHydro tidal turbine blade, PNNL teamed with colleagues from Sandia National Laboratories (SNL) to carry out an analysis of the mechanics and biological consequences of different blade strike scenarios. Results of these analyses found the following: 1) a SRKW is not likely to experience significant tissue injury from impact by an OpenHydro turbine blade; and 2) if whale skin behaves similarly to the materials considered as surrogates for the upper dermal layers of whale skin, it would not be torn by an OpenHydro blade strike. The PNNL/SNL analyses could not provide insight into the potential for more subtle changes to SRKWs from an encounter with a turbine, such as changes in behavior, or inform turbine interactions for other whales or other turbines. These analyses were limited by the available time frame in which results were needed and focused on the mechanical response of whale tissues and bone to blade strike. PNNL proposes that analyses of additional turbine designs and interactions with other marine mammals that differ in size, body conformation, and mass be performed.

  15. Performance Evaluation of HYCOM-GOM for Hydrokinetic Resource Assessment in the Florida Strait

    SciTech Connect (OSTI)

    Neary, Vincent S; Gunawan, Budi; Ryou, Albert S

    2012-06-01

    The U.S. Department of Energy (DoE) is assessing and mapping the potential off-shore ocean current hydrokinetic energy resources along the U.S. coastline, excluding tidal currents, to facilitate market penetration of water power technologies. This resource assessment includes information on the temporal and three-dimensional spatial distribution of the daily averaged power density, and the overall theoretical hydrokinetic energy production, based on modeled historical simulations spanning a 7-year period of record using HYCOM-GOM, an ocean current observation assimilation model that generates a spatially distributed three-dimensional representation of daily averaged horizontal current magnitude and direction time series from which power density time series and their statistics can be derived. This study ascertains the deviation of HYCOM-GOM outputs, including transport (flow) and power density, from outputs based on three independent observation sources to evaluate HYCOM-GOM performance. The three independent data sources include NOAA s submarine cable data of transport, ADCP data at a high power density location, and HF radar data in the high power density region of the Florida Strait. Comparisons with these three independent observation sets indicate discrepancies with HYCOM model outputs, but overall indicate that the HYCOM-GOM model can provide an adequate assessment of the ocean current hydrokinetic resource in high power density regions like the Florida Strait. Additional independent observational data, in particular stationary ADCP measurements, would be useful for expanding this model performance evaluation study. ADCP measurements are rare in ocean environments not influenced by tides, and limited to one location in the Florida Strait. HF radar data, although providing great spatial coverage, is limited to surface currents only.

  16. Tidal Energy System for On-Shore Power Generation

    SciTech Connect (OSTI)

    Bruce, Allan J

    2012-06-26

    Addressing the urgent need to develop LCOE competitive renewable energy solutions for US energy security and to replace fossil-fuel generation with the associated benefits to environment impacts including a reduction in CO2 emissions, this Project focused on the advantages of using hydraulic energy transfer (HET) in large-scale Marine Hydrokinetic (MHK) systems for harvesting off-shore tidal energy in US waters. A recent DOE resource assessment, identifies water power resources have a potential to meet 15% of the US electric supply by 2030, with MHK technologies being a major component. The work covered a TRL-4 laboratory proof-in-concept demonstration plus modeling of a 15MW full scale system based on an approach patented by NASA-JPL, in which submerged high-ratio gearboxes and electrical generators in conventional MHK turbine systems are replaced by a submerged hydraulic radial pump coupled to on-shore hydraulic motors driving a generator. The advantages are; first, the mean-time-between-failure (MTBF), or maintenance, can be extended from approximately 1 to 5 years and second, the range of tidal flow speeds which can be efficiently harvested can be extended beyond that of a conventional submerged generator. The approach uses scalable, commercial-off-the-shelf (COTS) components, facilitating scale-up and commercialization. All the objectives of the Project have been successfully met (1) A TRL4 system was designed, constructed and tested. It simulates a tidal energy turbine, with a 2-m diameter blade in up to a 2.9 m/sec flow. The system consists of a drive motor assembly providing appropriate torque and RPM, attached to a radial piston pump. The pump circulates pressurized, environmentally-friendly, HEES hydraulic fluid in a closed loop to an axial piston motor which drives an electrical generator, with a resistive load. The performance of the components, subsystems and system were evaluated during simulated tidal cycles. The pump is contained in a tank for immersion testing. The COTS pump and motor were selected to scale to MW size and were oversized for the TRL-4 demonstration, operating at only 1-6% of rated values. Nevertheless, in for 2-18 kW drive power, in agreement with manufacturer performance data, we measured efficiencies of 85-90% and 75-80% for the pump and motor, respectively. These efficiencies being 95-96% at higher operating powers. (2) Two follow-on paths were identified. In both cases conventional turbine systems can be modified, replacing existing gear box and generator with a hydraulic pump and on-shore components. On a conventional path, a TRL5/6 15kW turbine system can be engineered and tested on a barge at an existing site in Maine. Alternatively, on an accelerated path, a TRL-8 100kW system can be engineered and tested by modifying a team member's existing MHK turbines, with barge and grid-connected test sites in-place. On both paths the work can be expedited and cost effective by reusing TRL-4 components, modifying existing turbines and using established test sites. (3) Sizing, performance modeling and costing of a scaled 15MW system, suitable for operation in Maine's Western Passage, was performed. COTS components are identified and the performance projections are favorable. The estimated LCOE is comparable to wind generation with peak production at high demand times. (4) We determined that a similar HET approach can be extended to on-shore and off-shore wind turbine systems. These are very large energy resources which can be addressed in parallel for even great National benefit. (5) Preliminary results on this project were presented at two International Conferences on renewable energy in 2012, providing a timely dissemination of information. We have thus demonstrated a proof-in-concept of a novel, tidal HET system that eliminates all submerged gears and electronics to improve reliability. Hydraulic pump efficiencies of 90% have been confirmed in simulated tidal flows between 1 and 3 m/s, and at only 1-6% of rated power. Total system efficiencies have also been modeled, up to MW-scale, for ti

  17. PVGIS approach for assessing the performances of the first PV grid-connected power plant in Morocco

    E-Print Network [OSTI]

    Barhdadi, Abdelfettah

    2012-01-01

    In this paper, we apply the PVGIS method for estimating the performance of the first grid-connected PV micro-power plant in Morocco. PVGIS approach provides analysis and assessment of in-site solar energy resources and predicts with good accuracy the potential of PV systems in term of electricity production. We find that annual total power generation of the micro-power is slightly higher than that initially expected at the installation stage and actually measured. The yearly predicted and measured power production values agree to about 2 %. However, individual monthly production can have larger discrepancy.

  18. Proceedings of the Hydrokinetic and Wave Energy Technologies Technical and Environmental Issues Workshop

    SciTech Connect (OSTI)

    2006-03-01

    Renewable energy technologies offer the promise of non-polluting alternatives to fossil and nuclear-fueled power plants to meet growing demand for electrical energy. Two emerging categories of renewable energy technologies, hydrokinetic and wave energy conversion devices, offer ways to tap the energy of moving water without impoundment (dams) or diversion required by many conventional hydroelectric facilities. These technologies include devices designed for deployment in natural streams, tidal estuaries, ocean currents, and constructed waterways, as well as devices designed to capture the energy of ocean waves. On October 26-28, 2005, 54 representatives from government, non-governmental organizations, and private business met to (1) identify the varieties of hydrokinetic energy and wave technology devices, their stages of development, and the projected cost to bring each to market; (2) identify where these technologies can best operate; (3) identify the potential environmental issues associated with these technologies and possible mitigation measures; (4) develop a list of research needs and/or practical solutions to address unresolved environmental issues. These workshop proceedings include detailed summaries of the 24 presentations made and the discussions that followed.

  19. Three-Phase Modular Cascaded H-Bridge Multilevel Inverter with Individual MPPT for Grid-Connected Photovoltaic Systems

    SciTech Connect (OSTI)

    Xiao, Bailu [ORNL; Hang, Lijun [ORNL; Riley, Cameron [University of Tennessee, Knoxville (UTK); Tolbert, Leon M [ORNL; Ozpineci, Burak [ORNL

    2013-01-01

    A three-phase modular cascaded H-bridge multilevel inverter for a grid-connected photovoltaic (PV) system is presented in this paper. To maximize the solar energy extraction of each PV string, an individual maximum power point tracking (MPPT) control scheme is applied, which allows the independent control of each dc-link voltage. PV mismatches may introduce unbalanced power supplied to the three-phase system. To solve this issue, a control scheme with modulation compensation is proposed. The three-phase modular cascaded multilevel inverter prototype has been built. Each H-bridge is connected to a 185 W solar panel. Simulation and experimental results are presented to validate the proposed ideas.

  20. Abstract--This paper deals with the design of a nonlinear con-troller for single-phase grid-connected photovoltaic (PV) systems

    E-Print Network [OSTI]

    Pota, Himanshu Roy

    -connected photovoltaic (PV) systems to maintain the current injected into the grid in phase with grid voltage. This paper also deals with the stability of internal dynamics of PV systems which is a basic requirement in atmospheric conditions. Index Terms--DC link voltage, grid current, grid-connected PV system, maximum power

  1. IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, VOL. 57, NO. 10, OCTOBER 2010 3431 A Universal Grid-Connected Fuel-Cell Inverter for

    E-Print Network [OSTI]

    Mazumder, Sudip K.

    IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, VOL. 57, NO. 10, OCTOBER 2010 3431 A Universal Grid--This paper describes a universal fuel-cell-based grid- connected inverter design with digital. The critical design issues focus on the impact and optimization of transformer leakage inductance with regard

  2. A novel multi-model neuro-fuzzy-based MPPT for three-phase grid-connected photovoltaic system

    SciTech Connect (OSTI)

    Chaouachi, Aymen; Kamel, Rashad M.; Nagasaka, Ken

    2010-12-15

    This paper presents a novel methodology for Maximum Power Point Tracking (MPPT) of a grid-connected 20 kW photovoltaic (PV) system using neuro-fuzzy network. The proposed method predicts the reference PV voltage guarantying optimal power transfer between the PV generator and the main utility grid. The neuro-fuzzy network is composed of a fuzzy rule-based classifier and three multi-layered feed forwarded Artificial Neural Networks (ANN). Inputs of the network (irradiance and temperature) are classified before they are fed into the appropriated ANN for either training or estimation process while the output is the reference voltage. The main advantage of the proposed methodology, comparing to a conventional single neural network-based approach, is the distinct generalization ability regarding to the nonlinear and dynamic behavior of a PV generator. In fact, the neuro-fuzzy network is a neural network based multi-model machine learning that defines a set of local models emulating the complex and nonlinear behavior of a PV generator under a wide range of operating conditions. Simulation results under several rapid irradiance variations proved that the proposed MPPT method fulfilled the highest efficiency comparing to a conventional single neural network and the Perturb and Observe (P and O) algorithm dispositive. (author)

  3. Multnomah County Hydrokinetic Feasibility Study: Final Feasibility Study Report

    SciTech Connect (OSTI)

    Stephen Spain

    2012-03-15

    HDR has completed a study of the technical, regulatory, and economic feasibility of installing hydrokinetic turbines under the Morrison, Broadway, and Sellwood bridges. The primary objective of installing hydrokinetic turbines is a demonstration of in-stream hydrokinetic technologies for public education and outreach. Due to the low gradient of the Lower Willamette and the effects of the tide, velocities in the area in consideration are simply not high enough to economically support a commercial installation. While the velocities in the river may at times provide enough energy for a commercial turbine to reach capacity, the frequency and duration of high flow events which provide suitable velocities is not sufficient to support a commercial hydrokinetic installation. We have observed that over an 11 year period, daily average velocities in the Lower Willamette exceeded a nominal cut-in speed of 0.75 m/s only 20% of the time, leaving net zero power production for the remaining 80% of days. The Sellwood Bridge site was estimated to have the best hydrokinetic resource, with an estimated average annual production of about 9,000 kWh. The estimated production could range from 2,500 kWh to 15,000 kWh. Based on these energy estimates, the amount of revenue generated through either a power purchase agreement (PPA) or recovered through net metering is not sufficient to repay the project costs within the life of the turbine. The hydrokinetic resource at the Morrison and Broadway Bridges is slightly smaller than at the Sellwood Bridge. While the Broadway and Morrison Bridges have existing infrastructure that could be utilized, the project is not expected to generate enough revenue to repay the investment. Despite low velocities and energy production, the sites themselves are favorable for installation of a demonstration or experimental project. With high public interest in renewable energy, the possibility exists to develop a hydrokinetic test site which could provide developers and scientists a location to temporarily deploy and test hydrokinetic devices, and also function as an educational tool for the general public. Bridge piers provide an excellent pre-existing anchor point for hydrokinetic devices, and existing infrastructure at the Morrison and Broadway Bridges may reduce installation costs. Opportunity exists to partner with local universities with engineering and environmental interest in renewable energy. A partnership with Portland State University�¢����s engineering school could provide students with an opportunity to learn about hydrokinetics through senior design projects. Oregon State University and University of Washington, which are partnered through the Northwest National Marine Renewable Energy Center (NNMREC) to study and test hydrokinetic technology, are also relatively local to the site. In addition to providing an opportunity for both public and private entities to learn technically about in-stream kinetics, this approach will encourage grant funding for outreach, education, and product development, while also serving as a positive community relations opportunity for the County and its partners.

  4. April 30 Public Meeting: Physical Characterization of Smart and Grid-Connected Commercial and Residential Building End-Use Equipment and Appliances

    Broader source: Energy.gov [DOE]

    These documents contain slide decks presented at the Physical Characterization of Smart and Grid-Connected Commercial and Residential Buildings End-Use Equipment and Appliances public meeting held on April 30, 2014. The first document includes the first presentation from the meeting: DOE Vision and Objectives. The second document includes all other presentations from the meeting: Terminology and Definitions; End-User and Grid Services; Physical Characterization Framework; Value, Benefits & Metrics.

  5. Marine Hydrokinetic Energy Regulators Workshop: Lessons from Wind

    SciTech Connect (OSTI)

    Baring-Gould, E. Ian

    2015-09-03

    Ian Baring-Gould presented these lessons learned from wind energy to an audience of marine hydrokinetic regulators. Lessons learned spanned the areas of technology advances, using collaborative approaches to involve key stakeholders; using baseline studies to measure and prioritize wildlife impacts, and look at avoidance and mitigation options early in the process.

  6. Identifying How Marine and Hydrokinetic Devices Affect Aquatic Environments

    SciTech Connect (OSTI)

    Cada, G. F.; Copping, Andrea E.; Roberts, Jesse

    2011-04-24

    Significant research is under way to determine the potential environmental effects of marine and hydrokinetic energy systems. This research, being guided and funded by the U.S. Department of Energy, is intended to address knowledge gaps and facilitate installation and operation of these systems.

  7. Quadrennial Technology Review 2015: Technology Assessments--Marine and Hydrokinetic Power

    SciTech Connect (OSTI)

    Sam Baldwin, Gilbert Bindewald, Austin Brown, Charles Chen, Kerry Cheung, Corrie Clark, Joe Cresko,

    2015-10-07

    Marine and hydrokinetic (MHK) technologies convert the energy of waves, tides, and river and ocean currents into electricity. With more than 50% of the U.S. population living within 50 miles of the nation’s coasts, MHK technologies hold significant potential to supply renewable electricity to consumers in coastal load centers, particularly in the near term in areas with high costs of electricity and longer term in high resource areas in close proximity to major coastal load centers. MHK resource assessments identify a total U.S. technical resource potential of approximately 1250–1850 terawatt-hours (TWh) of generation per year from ocean wave, ocean current, ocean tidal, and river current energy. Of this, the U.S. continental technical resource potential is approximately 500–750 TWh/year. For context, roughly 90,000 homes can be powered by 1 TWh of electricity generation each year. A cost-effective MHK industry could provide a substantial amount of electricity for the nation owing in large part to its unique advantages as a source of energy, including its vast resource potential, its close proximity to major coastal load centers, and its long-term predictability and near-term forecastability.

  8. Hydro-kinetic approach to relativistic heavy ion collisions

    E-Print Network [OSTI]

    Akkelin, S V; Karpenko, Iu A; Sinyukov, Yu M

    2008-01-01

    We develop a combined hydro-kinetic approach which incorporates hydrodynamical expansion of the systems formed in \\textit{A}+\\textit{A} collisions and their dynamical decoupling described by escape probabilities. The method corresponds to a generalized relaxation time ($\\tau_{\\text{rel}}$) approximation for Boltzmann equation applied to inhomogeneous expanding systems; at small $\\tau_{\\text{rel}}$ it also allows one to catch the viscous effects in hadronic component - hadron-resonance gas. We demonstrate how the approximation of sudden freeze-out can be obtained within this dynamical picture of continuous emission and find that hypersurfaces, corresponding to sharp freeze-out limit, are momentum dependent. The pion $m_{T}$ spectra are computed in the developed hydro-kinetic model, and compared with those obtained from ideal hydrodynamics with the Cooper-Frye isothermal prescription. Our results indicate that there does not exist a universal freeze-out temperature for pions with different momenta, and support ...

  9. 2014 Water Power Program Peer Review: Marine and Hydrokinetic Technologies, Compiled Presentations (Presentation)

    SciTech Connect (OSTI)

    Not Available

    2014-02-01

    This document represents a collection of all presentations given during the EERE Wind and Water Power Program's 2014 Marine and Hydrokinetic Peer Review. The purpose of the meeting was to evaluate DOE-funded hydropower and marine and hydrokinetic R&D projects for their contribution to the mission and goals of the Water Power Program and to assess progress made against stated objectives.

  10. Modeling Tidal Stream Energy Extraction and its Effects on Transport Processes in a Tidal Channel and Bay System Using a Three-dimensional Coastal Ocean Model

    SciTech Connect (OSTI)

    Yang, Zhaoqing; Wang, Taiping; Copping, Andrea E.

    2013-02-28

    This paper presents a numerical modeling study for simulating in-stream tidal energy extraction and assessing its effects on the hydrodynamics and transport processes in a tidal channel and bay system connecting to coastal ocean. A marine and hydrokinetic (MHK) module was implemented in a three-dimensional (3-D) coastal ocean model using the momentum sink approach. The MHK model was validated with the analytical solutions for tidal channels under one-dimensional (1-D) conditions. Model simulations were further carried out to compare the momentum sink approach with the quadratic bottom friction approach. The effects of 3-D simulations on the vertical velocity profile, maximum extractable energy, and volume flux reduction across the channel were investigated through a series of numerical experiments. 3-D model results indicate that the volume flux reduction at the maximum extractable power predicted by the 1-D analytical model or two-dimensional (2-D) depth-averaged numerical model may be overestimated. Maximum extractable energy strongly depends on the turbine hub height in the water column, and which reaches a maximum when turbine hub height is located at mid-water depth. Far-field effects of tidal turbines on the flushing time of the tidal bay were also investigated. Model results demonstrate that tidal energy extraction has a greater effect on the flushing time than volume flux reduction, which could negatively affect the biogeochemical processes in estuarine and coastal waters that support primary productivity and higher forms of marine life.

  11. Laboratory Experiments on the Effects of Blade Strike from Hydrokinetic Energy Technologies on Larval and Juvenile Freshwater Fishes

    SciTech Connect (OSTI)

    Schweizer, Peter E; Cada, Glenn F; Bevelhimer, Mark S

    2012-03-01

    There is considerable interest in the development of marine and hydrokinetic energy projects in rivers, estuaries, and coastal ocean waters of the United States. Hydrokinetic (HK) technologies convert the energy of moving water in river or tidal currents into electricity, without the impacts of dams and impoundments associated with conventional hydropower or the extraction and combustion of fossil fuels. The Federal Energy Regulatory Commission (FERC) maintains a database that displays the geographical distribution of proposed HK projects in inland and tidal waters (FERC 2012). As of March 2012, 77 preliminary permits had been issued to private developers to study HK projects in inland waters, the development of which would total over 8,000 MW. Most of these projects are proposed for the lower Mississippi River. In addition, the issuance of another 27 preliminary permits for HK projects in inland waters, and 3 preliminary permits for HK tidal projects (totaling over 3,100 MW) were under consideration by FERC. Although numerous HK designs are under development (see DOE 2009 for a description of the technologies and their potential environmental effects), the most commonly proposed current-based projects entail arrays of rotating devices, much like submerged wind turbines, that are positioned in the high-velocity (high energy) river channels. The many diverse HK designs imply a diversity of environmental impacts, but a potential impact common to most is the risk for blade strike to aquatic organisms. In conventional hydropower generation, research on fish passage through reaction turbines at low-head dams suggested that strike and mortality for small fish could be low. As a consequence of the large surface area to mass ratio of small fish, the drag forces in the boundary layer flow at the surface of a rotor blade may pull small fish around the leading edge of a rotor blade without making physical contact (Turnpenny 1998, Turnpenny et al. 2000). Although there is concern that small, fragile fish early life stages may be unable to avoid being struck by the blades of hydrokinetic turbines, we found no empirical data in the published literature that document survival of earliest life-stage fish in passage by rotor blades. In addition to blade strike, research on passage of fish through conventional hydropower turbines suggested that fish mortalities from passage through the rotor swept area could also occur due to shear stresses and pressure chances in the water column (Cada et al. 1997, Turnpenny 1998). However, for most of the proposed HK turbine designs the rotors are projected to operate a lower RPM (revolutions per minute) than observed from conventional reaction turbines; the associated shear stress and pressure changes are expected to be lower and pose a smaller threat to fish survival (DOE 2009). Only a limited number of studies have been conducted to examine the risk of blade strike from hydrokinetic technologies to fish (Turnpenny et al. 1992, Normandeau et al. 2009, Seitz et al. 2011, EPRI 2011); the survival of drifting or weakly swimming fish (especially early life stages) that encounter rotor blades from hydrokinetic (HK) devices is currently unknown. Our study addressed this knowledge gap by testing how fish larvae and juveniles encountered different blade profiles of hydrokinetic devices and how such encounters influenced survivorship. We carried out a laboratory study designed to improve our understanding of how fish larvae and juvenile fish may be affected by encounters with rotor blades from HK turbines in the water column of river and ocean currents. (For convenience, these early life stages will be referred to as young of the year, YOY). The experiments developed information needed to quantify the risk (both probability and consequences) of rotor-blade strike to YOY fish. In particular, this study attempted to determine whether YOY drifting in a high-velocity flow directly in the path of the blade leading edge will make contact with the rotor blade or will bypass the blade while entrained in the boundary l

  12. MHK Projects/Indian River Tidal Hydrokinetic Energy Project | Open Energy

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas:Montezuma,Information MHKMHK5 < MHK ProjectsHawaii < MHK ProjectsITRI

  13. Marine & Hydrokinetic Technology Readiness Initiative TIDAL ENERGY SYSTEM FOR ON-SHORE POWER GENERATION

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield MunicipalTechnical Report:Speeding accessby aLED Street LightingFrom theHighI _s - "U N C- .

  14. JEDI Marine and Hydrokinetic Model: User Reference Guide

    SciTech Connect (OSTI)

    Goldberg, M.; Previsic, M.

    2011-04-01

    The Jobs and Economic Development Impact Model (JEDI) for Marine and Hydrokinetics (MHK) is a user-friendly spreadsheet-based tool designed to demonstrate the economic impacts associated with developing and operating MHK power systems in the United States. The JEDI MHK User Reference Guide was developed to assist users in using and understanding the model. This guide provides information on the model's underlying methodology, as well as the sources and parameters used to develop the cost data utilized in the model. This guide also provides basic instruction on model add-in features, operation of the model, and a discussion of how the results should be interpreted.

  15. Marine and Hydrokinetic Technology Glossary | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas:Montezuma,Information MHKMHK5TransportManitouChangeMarcMarine and Hydrokinetic

  16. Development of a low cost integrated 15 kW A.C. solar tracking sub-array for grid connected PV power system applications

    SciTech Connect (OSTI)

    Stern, M.; West, R.; Fourer, G.; Whalen, W.; Van Loo, M.; Duran, G.

    1997-02-01

    Utility Power Group has achieved a significant reduction in the installed cost of grid-connected PV systems. The two part technical approach focused on (1) The utilization of a large area factory assembled PV panel, and (2) The integration and packaging of all sub-array power conversion and control functions within a single factory produced enclosure. Eight engineering prototype 15kW ac single axis solar tracking sub-arrays were designed, fabricated, and installed at the Sacramento Municipal Utility District{close_quote}s Hedge Substation site in 1996 and are being evaluated for performance and reliability. A number of design enhancements will be implemented in 1997 and demonstrated by the field deployment and operation of over twenty advanced sub-array PV power systems. {copyright} {ital 1997 American Institute of Physics.}

  17. Tidal Energy Basics

    Broader source: Energy.gov [DOE]

    Some of the oldest ocean energy technologies use tidal power. For tidal differences to be harnessed into electricity, the difference between high and low tides must be more than 16 feet (or at least 5 meters). However, there are only about 40 sites on Earth with tidal ranges of this magnitude.

  18. Hydro-kinetic approach to relativistic heavy ion collisions

    E-Print Network [OSTI]

    S. V. Akkelin; Y. Hama; Iu. A. Karpenko; Yu. M. Sinyukov

    2008-08-28

    We develop a combined hydro-kinetic approach which incorporates a hydrodynamical expansion of the systems formed in \\textit{A}+\\textit{A} collisions and their dynamical decoupling described by escape probabilities. The method corresponds to a generalized relaxation time ($\\tau_{\\text{rel}}$) approximation for the Boltzmann equation applied to inhomogeneous expanding systems; at small $\\tau_{\\text{rel}}$ it also allows one to catch the viscous effects in hadronic component - hadron-resonance gas. We demonstrate how the approximation of sudden freeze-out can be obtained within this dynamical picture of continuous emission and find that hypersurfaces, corresponding to a sharp freeze-out limit, are momentum dependent. The pion $m_{T}$ spectra are computed in the developed hydro-kinetic model, and compared with those obtained from ideal hydrodynamics with the Cooper-Frye isothermal prescription. Our results indicate that there does not exist a universal freeze-out temperature for pions with different momenta, and support an earlier decoupling of higher $p_{T}$ particles. By performing numerical simulations for various initial conditions and equations of state we identify several characteristic features of the bulk QCD matter evolution preferred in view of the current analysis of heavy ion collisions at RHIC energies.

  19. Live Webinar on the Funding Opportunity for Marine and Hydrokinetic Research and Development University Consortium

    Office of Energy Efficiency and Renewable Energy (EERE)

    On April 24, 2014 from 1:00 - 2:30 PM EDT, the Water Power Program will hold a live webinar to provide information to potential applicants for the Marine and Hydrokinetic (MHK) Research and...

  20. Blanc, I., Beloin-Saint-Pierre, D., Payet, J., Jacquin, P., Adra, N., Mayer, D., Espace-PV: key sensitive parameters for environmental impacts of grid-connected PV systems with LCA , In Proceedings of the 23rd

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Blanc, I., Beloin-Saint-Pierre, D., Payet, J., Jacquin, P., Adra, N., Mayer, D., « Espace-PV: key sensitive parameters for environmental impacts of grid-connected PV systems with LCA », In Proceedings-936338-24-8, pp. 3779-3781. DOI: 10.4229/23rdEUPVSEC2008-6DV.5.9 ESPACE-PV: KEY SENSITIVE PARAMETERS

  1. Panel: Microgrid Research and Field Testing IEEE PES General Meeting, 24-28 June 2007, Tampa, FL 1 In general, a microgrid can operate in both the grid-connected

    E-Print Network [OSTI]

    Panel: Microgrid Research and Field Testing IEEE PES General Meeting, 24-28 June 2007, Tampa, FL 1 Abstract In general, a microgrid can operate in both the grid-connected mode and the islanded mode where the microgrid is interfaced to the main power system by a fast semiconductor switch called static switch, (SS

  2. Marine and Hydrokinetic Energy Development Technical Support and General Environmental Studies Report on Outreach to Stakeholders for Fiscal Year 2009

    SciTech Connect (OSTI)

    Copping, Andrea E.; Geerlofs, Simon H.

    2010-01-22

    Report on activities working with stakeholders in the emerging marine and hydrokinetic energy industry during FY09, for DOE EERE Office of Waterpower.

  3. Puget Sound Tidal Energy In-Water Testing and Development Project Final Technical Report

    SciTech Connect (OSTI)

    Craig W. Collar

    2012-11-16

    Tidal energy represents potential for the generation of renewable, emission free, environmentally benign, and cost effective energy from tidal flows. A successful tidal energy demonstration project in Puget Sound, Washington may enable significant commercial development resulting in important benefits for the northwest region and the nation. This project promoted the United States Department of Energy�s Wind and Hydropower Technologies Program�s goals of advancing the commercial viability, cost-competitiveness, and market acceptance of marine hydrokinetic systems. The objective of the Puget Sound Tidal Energy Demonstration Project is to conduct in-water testing and evaluation of tidal energy technology as a first step toward potential construction of a commercial-scale tidal energy power plant. The specific goal of the project phase covered by this award was to conduct all activities necessary to complete engineering design and obtain construction approvals for a pilot demonstration plant in the Admiralty Inlet region of the Puget Sound. Public Utility District No. 1 of Snohomish County (The District) accomplished the objectives of this award through four tasks: Detailed Admiralty Inlet Site Studies, Plant Design and Construction Planning, Environmental and Regulatory Activities, and Management and Reporting. Pre-Installation studies completed under this award provided invaluable data used for site selection, environmental evaluation and permitting, plant design, and construction planning. However, these data gathering efforts are not only important to the Admiralty Inlet pilot project. Lessons learned, in particular environmental data gathering methods, can be applied to future tidal energy projects in the United States and other parts of the world. The District collaborated extensively with project stakeholders to complete the tasks for this award. This included Federal, State, and local government agencies, tribal governments, environmental groups, and others. All required permit and license applications were completed and submitted under this award, including a Final License Application for a pilot hydrokinetic license from the Federal Energy Regulatory Commission. The tasks described above have brought the project through all necessary requirements to construct a tidal pilot project in Admiralty Inlet with the exception of final permit and license approvals, and the selection of a general contractor to perform project construction.

  4. THORs Power Method for Hydrokinetic Devices - Final Report

    SciTech Connect (OSTI)

    J. Turner Hunt; Joel Rumker

    2012-08-08

    Ocean current energy represents a vast untapped source of renewable energy that exists on the outer continental shelf areas of the 5 major continents. Ocean currents are unidirectional in nature and are perpetuated by thermal and salinity sea gradients, as well as coriolis forces imparted from the earth's rotation. This report details THORs Power Method, a breakthrough power control method that can provide dramatic increases to the capacity factor over and above existing marine hydrokinetic (MHK) devices employed in the extraction of energy from ocean currents. THORs Power Method represents a constant speed, variable depth operational method that continually locates the ocean current turbine at a depth at which the rated power of the generator is routinely achieved. Variable depth operation is achieved by using various vertical force effectors, including ballast tanks for variable weight, a hydrodynamic wing for variable lift or down force and drag flaps for variable vehicle drag forces.

  5. Clarence Strait Tidal Energy Project, Tenax Energy Tropical Tidal...

    Open Energy Info (EERE)

    Page Edit History Clarence Strait Tidal Energy Project, Tenax Energy Tropical Tidal Test Centre, Jump to: navigation, search 1 Retrieved from "http:en.openei.orgw...

  6. Acoustic Monitoring of Beluga Whale Interactions with Cook Inlet Tidal Energy Project

    SciTech Connect (OSTI)

    Worthington, Monty

    2014-02-05

    Cook Inlet, Alaska is home to some of the greatest tidal energy resources in the U.S., as well as an endangered population of beluga whales (Delphinapterus leucas). Successfully permitting and operating a tidal power project in Cook Inlet requires a biological assessment of the potential and realized effects of the physical presence and sound footprint of tidal turbines on the distribution, relative abundance, and behavior of Cook Inlet beluga whales. ORPC Alaska, working with the Project Team—LGL Alaska Research Associates, University of Alaska Anchorage, TerraSond, and Greeneridge Science—undertook the following U.S. Department of Energy (DOE) study to characterize beluga whales in Cook Inlet – Acoustic Monitoring of Beluga Whale Interactions with the Cook Inlet Tidal Energy Project (Project). ORPC Alaska, LLC, is a wholly-owned subsidiary of Ocean Renewable Power Company, LLC, (collectively, ORPC). ORPC is a global leader in the development of hydrokinetic power systems and eco-conscious projects that harness the power of ocean and river currents to create clean, predictable renewable energy. ORPC is developing a tidal energy demonstration project in Cook Inlet at East Foreland where ORPC has a Federal Energy Regulatory Commission (FERC) preliminary permit (P-13821). The Project collected baseline data to characterize pre-deployment patterns of marine mammal distribution, relative abundance, and behavior in ORPC’s proposed deployment area at East Foreland. ORPC also completed work near Fire Island where ORPC held a FERC preliminary permit (P-12679) until March 6, 2013. Passive hydroacoustic devices (previously utilized with bowhead whales in the Beaufort Sea) were adapted for study of beluga whales to determine the relative abundance of beluga whale vocalizations within the proposed deployment areas. Hydroacoustic data collected during the Project were used to characterize the ambient acoustic environment of the project site pre-deployment to inform the FERC pilot project process. The Project compared results obtained from this method to results obtained from other passive hydrophone technologies and to visual observation techniques performed simultaneously. This Final Report makes recommendations on the best practice for future data collection, for ORPC’s work in Cook Inlet specifically, and for tidal power projects in general. This Project developed a marine mammal study design and compared technologies for hydroacoustic and visual data collection with potential for broad application to future tidal and hydrokinetic projects in other geographic areas. The data collected for this Project will support the environmental assessment of future Cook Inlet tidal energy projects, including ORPC’s East Foreland Tidal Energy Project and any tidal energy developments at Fire Island. The Project’s rigorous assessment of technology and methodologies will be invaluable to the hydrokinetic industry for developing projects in an environmentally sound and sustainable way for areas with high marine mammal activity or endangered populations. By combining several different sampling methods this Project will also contribute to the future preparation of a comprehensive biological assessment of ORPC’s projects in Cook Inlet.

  7. Marine and Hydrokinetic Renewable Energy Devices, Potential Navigational Hazards and Mitigation Measures

    SciTech Connect (OSTI)

    Cool, Richard, M.; Hudon, Thomas, J.; Basco, David, R.; Rondorf, Neil, E.

    2009-12-01

    On April 15, 2008, the Department of Energy (DOE) issued a Funding Opportunity Announcement for Advanced Water Power Projects which included a Topic Area for Marine and Hydrokinetic Renewable Energy Market Acceleration Projects. Within this Topic Area, DOE identified potential navigational impacts of marine and hydrokinetic renewable energy technologies and measures to prevent adverse impacts on navigation as a sub-topic area. DOE defines marine and hydrokinetic technologies as those capable of utilizing one or more of the following resource categories for energy generation: ocean waves; tides or ocean currents; free flowing water in rivers or streams; and energy generation from the differentials in ocean temperature. PCCI was awarded Cooperative Agreement DE-FC36-08GO18177 from the DOE to identify the potential navigational impacts and mitigation measures for marine hydrokinetic technologies. A technical report addressing our findings is available on this Science and Technology Information site under the Product Title, "Marine and Hydrokinetic Renewable Energy Technologies: Potential Navigational Impacts and Mitigation Measures". This product is a brochure, primarily for project developers, that summarizes important issues in that more comprehensive report, identifies locations where that report can be downloaded, and identifies points of contact for more information.

  8. DISCRETE ELEMENT MODELING OF BLADE–STRIKE FREQUENCY AND SURVIVAL OF FISH PASSING THROUGH HYDROKINETIC TURBINES

    SciTech Connect (OSTI)

    Romero Gomez, Pedro DJ; Richmond, Marshall C.

    2014-04-17

    Evaluating the consequences from blade-strike of fish on marine hydrokinetic (MHK) turbine blades is essential for incorporating environmental objectives into the integral optimization of machine performance. For instance, experience with conventional hydroelectric turbines has shown that innovative shaping of the blade and other machine components can lead to improved designs that generate more power without increased impacts to fish and other aquatic life. In this work, we used unsteady computational fluid dynamics (CFD) simulations of turbine flow and discrete element modeling (DEM) of particle motion to estimate the frequency and severity of collisions between a horizontal axis MHK tidal energy device and drifting aquatic organisms or debris. Two metrics are determined with the method: the strike frequency and survival rate estimate. To illustrate the procedure step-by-step, an exemplary case of a simple runner model was run and compared against a probabilistic model widely used for strike frequency evaluation. The results for the exemplary case showed a strong correlation between the two approaches. In the application case of the MHK turbine flow, turbulent flow was modeled using detached eddy simulation (DES) in conjunction with a full moving rotor at full scale. The CFD simulated power and thrust were satisfactorily comparable to experimental results conducted in a water tunnel on a reduced scaled (1:8.7) version of the turbine design. A cloud of DEM particles was injected into the domain to simulate fish or debris that were entrained into the turbine flow. The strike frequency was the ratio of the count of colliding particles to the crossing sample size. The fish length and approaching velocity were test conditions in the simulations of the MHK turbine. Comparisons showed that DEM-based frequencies tend to be greater than previous results from Lagrangian particles and probabilistic models, mostly because the DEM scheme accounts for both the geometric aspects of the passage event ---which the probabilistic method does--- as well as the fluid-particle interactions ---which the Lagrangian particle method does. The DEM-based survival rates were comparable to laboratory results for small fish but not for mid-size fish because of the considerably different turbine diameters. The modeling framework can be used for applications that aim at evaluating the biological performance of MHK turbine units during the design phase and to provide information to regulatory agencies needed for the environmental permitting process.

  9. A 24-h forecast of solar irradiance using artificial neural network: Application for performance prediction of a grid-connected PV plant at Trieste, Italy

    SciTech Connect (OSTI)

    Mellit, Adel; Pavan, Alessandro Massi

    2010-05-15

    Forecasting of solar irradiance is in general significant for planning the operations of power plants which convert renewable energies into electricity. In particular, the possibility to predict the solar irradiance (up to 24 h or even more) can became - with reference to the Grid Connected Photovoltaic Plants (GCPV) - fundamental in making power dispatching plans and - with reference to stand alone and hybrid systems - also a useful reference for improving the control algorithms of charge controllers. In this paper, a practical method for solar irradiance forecast using artificial neural network (ANN) is presented. The proposed Multilayer Perceptron MLP-model makes it possible to forecast the solar irradiance on a base of 24 h using the present values of the mean daily solar irradiance and air temperature. An experimental database of solar irradiance and air temperature data (from July 1st 2008 to May 23rd 2009 and from November 23rd 2009 to January 24th 2010) has been used. The database has been collected in Trieste (latitude 45 40'N, longitude 13 46'E), Italy. In order to check the generalization capability of the MLP-forecaster, a K-fold cross-validation was carried out. The results indicate that the proposed model performs well, while the correlation coefficient is in the range 98-99% for sunny days and 94-96% for cloudy days. As an application, the comparison between the forecasted one and the energy produced by the GCPV plant installed on the rooftop of the municipality of Trieste shows the goodness of the proposed model. (author)

  10. Simulating Environmental Changes Due to Marine Hydrokinetic Energy Installations

    E-Print Network [OSTI]

    Siefert, Chris

    increasing attention upon renewable energy as a global solution to both energy and environmental challenges. Renewable energy sources such as wind power, solar power, or hydroelectric dams are increasingly implemented their potential environmental effects. When MHK devices extract energy from a system, volumetric flows and tidal

  11. Wave and Hydrokinetics Interest Group 1st Meeting of 2009/2010 Year

    E-Print Network [OSTI]

    Wave and Hydrokinetics Interest Group 1st Meeting of 2009/2010 Year: With a Focus on wave Energy, Inc. All rights reserved. Marine Wave Energy Interest Group · Bill Toman, PG&E WaveConnect Project Manager is Chairman · Agenda 8:30-9:00 USA Project Status: PG&E WaveConnect, OPT Reedsport and Coos Bay

  12. Effects of Large Energetic Vortices on Axial-Flow Hydrokinetic Turbines B. Gunawan1

    E-Print Network [OSTI]

    Siefert, Chris

    Effects of Large Energetic Vortices on Axial-Flow Hydrokinetic Turbines B. Gunawan1 , V.S. Neary1 C production in a model MHK turbine. Results show that the power generated by the turbine is significantly at the centerline of the energy extraction plane, or axial-flow turbine hub elevation, provide high resolution

  13. Siting Study Framework and Survey Methodology for Marine and Hydrokinetic Energy Projects in Offshore Southeast Florida

    SciTech Connect (OSTI)

    Vinick, Charles

    2011-09-26

    Presentation from the 2011 Water Peer Review in which principal investigator discusses project progess to Investigate areas offshore southeast Florida that appeared most suitable for siting of marine and hydrokinetic energy conversion facilities that may be proposed in the Atlantic Ocean offshore of southeast Florida.

  14. Marine and Hydrokinetic Renewable Energy Technologies: Potential Navigational Impacts and Mitigation Measures

    SciTech Connect (OSTI)

    Cool, Richard, M.; Hudon, Thomas, J.; Basco, David, R.; Rondorf, Neil, E.

    2009-12-10

    On April 15, 2008, the Department of Energy (DOE) issued a Funding Opportunity Announcement for Advanced Water Power Projects which included a Topic Area for Marine and Hydrokinetic Renewable Energy Market Acceleration Projects. Within this Topic Area, DOE identified potential navigational impacts of marine and hydrokinetic renewable energy technologies and measures to prevent adverse impacts on navigation as a sub-topic area. DOE defines marine and hydrokinetic technologies as those capable of utilizing one or more of the following resource categories for energy generation: ocean waves; tides or ocean currents; free flowing water in rivers or streams; and energy generation from the differentials in ocean temperature. PCCI was awarded Cooperative Agreement DE-FC36-08GO18177 from the DOE to identify the potential navigational impacts and mitigation measures for marine hydrokinetic technologies, as summarized herein. The contract also required cooperation with the U.S. Coast Guard (USCG) and two recipients of awards (Pacific Energy Ventures and reVision) in a sub-topic area to develop a protocol to identify streamlined, best-siting practices. Over the period of this contract, PCCI and our sub-consultants, David Basco, Ph.D., and Neil Rondorf of Science Applications International Corporation, met with USCG headquarters personnel, with U.S. Army Corps of Engineers headquarters and regional personnel, with U.S. Navy regional personnel and other ocean users in order to develop an understanding of existing practices for the identification of navigational impacts that might occur during construction, operation, maintenance, and decommissioning. At these same meetings, “standard” and potential mitigation measures were discussed so that guidance could be prepared for project developers. Concurrently, PCCI reviewed navigation guidance published by the USCG and international community. This report summarizes the results of this effort, provides guidance in the form of a checklist for assessing the navigational impacts of potential marine and hydrokinetic projects, and provides guidance for improving the existing navigational guidance promulgated by the USCG in Navigation Vessel Inspection Circular 02 07. At the request of the USCG, our checklist and mitigation guidance was written in a generic nature so that it could be equally applied to offshore wind projects. PCCI teleconferenced on a monthly basis with DOE, Pacific Energy Ventures and reVision in order to share information and review work products. Although the focus of our effort was on marine and hydrokinetic technologies, as defined above, this effort drew upon earlier work by the USCG on offshore wind renewable energy installations. The guidance provided herein can be applied equally to marine and hydrokinetic technologies and to offshore wind, which are collectively referred to by the USCG as Renewable Energy Installations.

  15. Live Webinar on the Marine and Hydrokinetic Demonstrations at The Navy's Wave Energy Test Site Funding Opportunity Announcement

    Broader source: Energy.gov [DOE]

    On Wednesday, May 7, 2014 from 3:00 PM - 4:30 PM EDT the Water Power Program will hold an informational webinar on the Marine and Hydrokinetic (MHK) Demonstrations at The Navy's Wave Energy Test...

  16. US Synthetic Corp (TRL 4 Component)- The Development of Open, Water Lubricated Polycrystalline Diamond Thrust Bearings for use in Marine Hydrokinetic (MHK) Energy Machines

    Broader source: Energy.gov [DOE]

    US Synthetic Corp (TRL 4 Component) - The Development of Open, Water Lubricated Polycrystalline Diamond Thrust Bearings for use in Marine Hydrokinetic (MHK) Energy Machines

  17. Environmental Effects of Sediment Transport Alteration and Impacts on Protected Species: Edgartown Tidal Energy Project

    SciTech Connect (OSTI)

    Barrett, Stephen B.; Schlezinger, David, Ph.D; Cowles, Geoff, Ph.D; Hughes, Patricia; Samimy; Roland, I.; and Terray, E, Ph.D.

    2012-12-29

    The Islands of Martha�¢����s Vineyard and Nantucket are separated from the Massachusetts mainland by Vineyard and Nantucket Sounds; water between the two islands flows through Muskeget Channel. The towns of Edgartown (on Martha�¢����s Vineyard) and Nantucket recognize that they are vulnerable to power supply interruptions due to their position at the end of the power grid, and due to sea level rise and other consequences of climate change. The tidal energy flowing through Muskeget Channel has been identified by the Electric Power Research Institute as the strongest tidal resource in Massachusetts waters. The Town of Edgartown proposes to develop an initial 5 MW (nameplate) tidal energy project in Muskeget Channel. The project will consist of 14 tidal turbines with 13 providing electricity to Edgartown and one operated by the University of Massachusetts at Dartmouth for research and development. Each turbine will be 90 feet long and 50 feet high. The electricity will be brought to shore by a submarine cable buried 8 feet below the seabed surface which will landfall in Edgartown either on Chappaquiddack or at Katama. Muskeget Channel is located between Martha�¢����s Vineyard and Nantucket. Its depth ranges between 40 and 160 feet in the deepest portion. It has strong currents where water is transferred between Nantucket Sound and the Atlantic Ocean continental shelf to the south. This makes it a treacherous passage for navigation. Current users of the channel are commercial and recreational fishing, and cruising boats. The US Coast Guard has indicated that the largest vessel passing through the channel is a commercial scallop dragger with a draft of about 10 feet. The tidal resource in the channel has been measured by the University of Massachusetts-Dartmouth and the peak velocity flow is approximately 5 knots. The technology proposed is the helical Gorlov-type turbine positioned with a horizontal axis that is positively buoyant in the water column and held down by anchors. This is the same technology proposed by Ocean Renewable Power Company in the Western Passage and Cobscook Bay near Eastport Maine. The blades rotate in two directions capturing the tides energy both during flood and ebb tides. The turbines will be anchored to the bottom and suspended in the water column. Initial depth of the turbines is expected to be about 25 feet below the surface to avoid impacting navigation while also capturing the strongest currents. The Town of Edgartown was initially granted a Preliminary Permit by the Federal Energy Regulatory Commission (FERC) on March 1, 2008, and has recently received a second permit valid through August 2014. The Preliminary Permit gives Edgartown the exclusive right to apply for a power generation license for power generated from the hydrokinetic energy in the water flowing in this area. Edgartown filed a Draft Pilot License Application with FERC on February 1, 2010 and an Expanded Environmental Notification Form with the Massachusetts Environmental Policy Act (MEPA) Office at the same time. It expects to file a Final License Application in late 2013. Harris Miller Miller & Hanson (HMMH) of Burlington Massachusetts is acting as the Project Manager for the Town of Edgartown and collaborating with other partners of the project including the University of Massachusetts - Dartmouth's Marine Renewable Energy Center and the Massachusetts Clean Energy Center. HMMH was awarded a grant under the Department of Energy's Advanced Water Program to conduct marine science and hydrokinetic site-specific environmental studies for projects actively seeking a FERC License. HMMH, on behalf of the Town, is managing this comprehensive study of the marine environment in Muskeget Channel and potential impacts of the tidal project on indicator species and habitats. The University of Massachusetts School of Marine Science and Technology (SMAST) conducted oceanographic studies of tidal currents, tide level, benthic habit

  18. Report to Congress on the Potential Environmental Effects of Marine and Hydrokinetic Energy Technologies

    SciTech Connect (OSTI)

    Cada, Glenn

    2009-12-01

    This report focuses on potential impacts of marine and hydrokinetic technologies to aquatic environments (i.e. rivers, estuaries, and oceans), fish and fish habitats, ecological relationships, and other marine and freshwater aquatic resources. The report does not address impacts to terrestrial ecosystems and organisms that are common to other electricity-generating technologies (e.g., construction and maintenance of transmission lines) or possible effects on the human environment, including: human use conflicts, aesthetics, viewsheds, noise in the terrestrial environment, light, recreation, transportation, navigation, cultural resources, socioeconomic impacts.

  19. 2011 Marine Hydrokinetic Device Modeling Workshop: Final Report; March 1, 2011

    SciTech Connect (OSTI)

    Li, Y.; Reed, M.; Smith, B.

    2011-10-01

    This report summarizes the NREL Marine and Hydrokinetic Device Modeling Workshop. The objectives for the modeling workshop were to: (1) Review the designs of existing MHK device prototypes and discuss design and optimization procedures; (2) Assess the utility and limitations of modeling techniques and methods presently used for modeling MHK devices; (3) Assess the utility and limitations of modeling methods used in other areas, such as naval architecture and ocean engineering (e.g., oil & gas industry); and (4) Identify the necessary steps to link modeling with other important components that analyze MHK devices (e.g., tank testing, PTO design, mechanical design).

  20. Microsoft PowerPoint - MVD Hydrokinetics, SW Regional Hydropower Conference, 10 June 2010, rev 1.pptx

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shines light on darkMicroorganismsnow widely usingOverview ofWeSchoolHydrokinetic

  1. Chapter 4: Advancing Clean Electric Power Technologies | Marine and Hydrokinetic Power Technology Assessment

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergyTher i n c i p a lCaribElectricSouthApplying caulk to 13.1Carbon DioxideHydrokinetic

  2. Measurement of velocity deficit at the downstream of a 1:10 axial hydrokinetic turbine B. Gunawan1

    E-Print Network [OSTI]

    Siefert, Chris

    plane from upstream to downstream of the turbine at x/D = -10, -5, -3, -2, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10Measurement of velocity deficit at the downstream of a 1:10 axial hydrokinetic turbine model B, Minneapolis, MN 55414. ABSTRACT Wake recovery constrains the downstream spacing and density of turbines

  3. Title: Sustainable Communities Based on a New Clean Energy Source -Marine & Hydrokinetic Power: Roosevelt Island and Beyond

    E-Print Network [OSTI]

    Walter, M.Todd

    Title: Sustainable Communities Based on a New Clean Energy Source - Marine & Hydrokinetic Power Earth Hour "a symbol of our commitment to sustainable energy for all," and underscored the need to "fuel in September launched an initiative to achieve universal and sustainable access to this vital resource, called

  4. Estimation of the Risks of Collision or Strike to Freshwater Aquatic Organisms Resulting from Operation of Instream Hydrokinetic Turbines

    SciTech Connect (OSTI)

    Schweizer, Peter E; Cada, Glenn F; Bevelhimer, Mark S

    2010-05-01

    Hydrokinetic energy technologies have been proposed as renewable, environmentally preferable alternatives to fossil fuels for generation of electricity. Hydrokinetic technologies harness the energy of water in motion, either from waves, tides or from river currents. For energy capture from free-flowing rivers, arrays of rotating devices are most commonly proposed. The placement of hydrokinetic devices in large rivers is expected to increase the underwater structural complexity of river landscapes. Moore and Gregory (1988) found that structural complexity increased local fish populations because fish and other aquatic biota are attracted to structural complexity that provides microhabitats with steep flow velocity gradients (Liao 2007). However, hydrokinetic devices have mechanical parts, blades, wings or bars that move through the water column, posing a potential strike or collision risk to fish and other aquatic biota. Furthermore, in a setting with arrays of hydrokinetic turbines the cumulative effects of multiple encounters may increase the risk of strike. Submerged structures associated with a hydrokinetic (HK) project present a collision risk to aquatic organisms and diving birds (Cada et al. 2007). Collision is physical contact between a device or its pressure field and an organism that may result in an injury to that organism (Wilson et al. 2007). Collisions can occur between animals and fixed submerged structures, mooring equipment, horizontal or vertical axis turbine rotors, and structures that, by their individual design or in combination, may form traps. This report defines strike as a special case of collision where a moving part, such as a rotor blade of a HK turbine intercepts the path of an organism of interest, resulting in physical contact with the organism. The severity of a strike incidence may range from minor physical contact with no adverse effects to the organism to severe strike resulting in injury or death of the organism. Harmful effects to animal populations could occur directly (e.g., from strike mortality of individuals) or indirectly (e.g., if the loss of prey species to strike reduces food for predators). Although actively swimming or passively drifting animals may collide with any of the physical structures associated with hydrokinetic devices, turbine rotors are the most likely sources for risk of strike or significant collision (DOE 2009). It is also possible that during a close encounter with a HK device no physical contact will be made between the device and the organism, either because the animal avoids the device by successfully changing its direction of movement, or by successfully evading any moving parts of the device. Oak Ridge National Laboratory (ORNL) has been funded by the US Department of Energy (DOE) Waterpower Program to evaluate strike potential and consequences for Marine and Hydrokinetic (MHK) technologies in rivers and estuaries of the United States. We will use both predictive models and laboratory/field experiments to evaluate the likelihood and consequences of strike at HK projects in rivers. Efforts undertaken at ORNL address three objectives: (1) Assess strike risk for marine and freshwater organisms; (2) Develop experimental procedures to assess the risk and consequences of strike; and (3) Conduct strike studies in experimental flumes and field installations of hydrokinetic devices. During the first year of the study ORNL collected information from the Federal Energy Regulatory Commission (FERC) MHK database about geographical distribution of proposed hydrokinetic projects (what rivers or other types of systems), HK turbine design (horizontal axis, vertical axis, other), description of proposed axial turbine (number of blades, size of blades, rotation rate, mitigation measures), and number of units per project. Where site specific information was available, we compared the location of proposed projects rotors within the channel (e.g., along cutting edge bank, middle of thalweg, near bottom or in midwater) to the general locations of fish in the river (shoreline,

  5. International Standards Development for Marine and Hydrokinetic Renewable Energy - Final Report on Technical Status

    SciTech Connect (OSTI)

    Rondorf, Neil E.; Busch, Jason; Kimball, Richard

    2011-10-29

    This report summarizes the progress toward development of International Standards for Marine and Hydrokinetic Renewable Energy, as funded by the U.S. Department of Energy (DOE) under the International Electrotechnical Commission (IEC) Technical Committee 114. The project has three main objectives: 1. Provide funding to support participation of key U.S. industry technical experts in 6 (originally 4) international working groups and/or project teams (the primary standards-making committees) and to attend technical meetings to ensure greater U.S. involvement in the development of these standards. 2. Provide a report to DOE and industry stakeholders summarizing the IEC standards development process for marine and hydrokinetic renewable energy, new international standards and their justifications, and provide standards guidance to industry members. 3. Provide a semi-annual (web-based) newsletter to the marine renewable energy community. The newsletter will educate industry members and stakeholders about the processes, progress, and needs of the US efforts to support the international standards development effort. The newsletter is available at www.TC114.us

  6. Temperature and Tidal Dynamics in a Branching Estuarine System

    E-Print Network [OSTI]

    Wagner, Richard Wayne

    2012-01-01

    distribution of tidal energy. When specific locations ordissipation which may alter tidal energy in other parts ofAdditionally, changes to tidal energy reflection within a

  7. Microsoft Word - RM1_Tidal Turbine_UW Tidal Resource-Abstract...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    turbine operating in a narrow, tidal channel. The site is a generalized version of Tacoma Narrows, Puget Sound, Washington. The resource is a mixed, mainly semidiurnal tidal...

  8. DOE in the News: Tidal Power in Maine on PBS Newshour | Department...

    Broader source: Energy.gov (indexed) [DOE]

    for Information Regarding a Proposed Funding Opportunity for Administration of the Wave Energy Converter Prize Upcoming Funding Opportunity for Marine and Hydrokinetic...

  9. Sandia Energy - EC Publications

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    HEALTH MONITORING OF MARINE HYDROKINETIC STRUCTURES (91) Field Measurements at River and Tidal Current Sites for Hydrokinetic Energy Development: Best Practices Manual (40) Flow...

  10. Remote Monitoring of the Structural Health of Hydrokinetic Composite Turbine Blades

    SciTech Connect (OSTI)

    J.L. Rovey K. Chandrashekhara

    2012-09-21

    A health monitoring approach is investigated for hydrokinetic turbine blade applications. In-service monitoring is critical due to the difficult environment for blade inspection and the cost of inspection downtime. Composite blade designs have advantages that include long life in marine environments and great control over mechanical properties. Experimental strain characteristics are determined for static loads and free-vibration loads. These experiments are designed to simulate the dynamic characteristics of hydrokinetic turbine blades. Carbon/epoxy symmetric composite laminates are manufactured using an autoclave process. Four-layer composite beams, eight-layer composite beams, and two-dimensional eight-layer composite blades are instrumented for strain. Experimental results for strain measurements from electrical resistance gages are validated with theoretical characteristics obtained from in-house finite-element analysis for all sample cases. These preliminary tests on the composite samples show good correlation between experimental and finite-element strain results. A health monitoring system is proposed in which damage to a composite structure, e.g. delamination and fiber breakage, causes changes in the strain signature behavior. The system is based on embedded strain sensors and embedded motes in which strain information is demodulated for wireless transmission. In-service monitoring is critical due to the difficult environment for blade inspection and the cost of inspection downtime. Composite blade designs provide a medium for embedding sensors into the blades for in-situ health monitoring. The major challenge with in-situ health monitoring is transmission of sensor signals from the remote rotating reference frame of the blade to the system monitoring station. In the presented work, a novel system for relaying in-situ blade health measurements in hydrokinetic systems is described and demonstrated. An ultrasonic communication system is used to transmit sensor data underwater from the rotating frame of the blade to a fixed relay station. Data are then broadcast via radio waves to a remote monitoring station. Results indicate that the assembled system can transmit simulated sensor data with an accuracy of ±5% at a maximum sampling rate of 500 samples/sec. A power investigation of the transmitter within the blade shows that continuous max-sampling operation is only possible for short durations (~days), and is limited due to the capacity of the battery power source. However, intermittent sampling, with long periods between samples, allows for the system to last for very long durations (~years). Finally, because the data transmission system can operate at a high sampling rate for short durations or at a lower sampling rate/higher duty cycle for long durations, it is well-suited for short-term prototype and environmental testing, as well as long-term commercially-deployed hydrokinetic machines.

  11. Tidal evolution of close binary asteroid systems

    E-Print Network [OSTI]

    Taylor, PA; Margot, JL

    2010-01-01

    a positive fractional power of the tidal frequency (at leasttidal bulges of the components as these will depend on the square (or higher powers)power, natural deviations from a spherical shape may exceed the amplitude of the tidal

  12. Simulating Blade-Strike on Fish passing through Marine Hydrokinetic Turbines

    SciTech Connect (OSTI)

    Romero Gomez, Pedro DJ; Richmond, Marshall C.

    2014-06-16

    The study reported here evaluated the occurrence, frequency, and intensity of blade strike of fish on an axial-flow marine hydrokinetic turbine by using two modeling approaches: a conventional kinematic formulation and a proposed Lagrangian particle- based scheme. The kinematic model included simplifying assumptions of fish trajectories such as distribution and velocity. The proposed method overcame the need for such simplifications by integrating the following components into a computational fluid dynamics (CFD) model: (i) advanced eddy-resolving flow simulation, (ii) generation of ambient turbulence based on field data, (iii) moving turbine blades in highly transient flows, and (iv) Lagrangian particles to mimic the potential fish pathways. The test conditions to evaluate the blade-strike probability and fish survival rate were: (i) the turbulent environment, (ii) the fish size, and (iii) the approaching flow velocity. The proposed method offered the ability to produce potential fish trajectories and their interaction with the rotating turbine. Depending upon the scenario, the percentile of particles that registered a collision event ranged from 6% to 19% of the released sample size. Next, by using a set of experimental correlations of the exposure-response of living fish colliding with moving blades, the simulated collision data were used as input variables to estimate the survival rate of fish passing through the operating turbine. The resulting survival rates were greater than 96% in all scenarios, which is comparable to or better than known survival rates for conventional hydropower turbines. The figures of strike probability and mortality rate were amplified by the kinematic model. The proposed method offered the advantage of expanding the evaluation of other mechanisms of stress and injury on fish derived from hydrokinetic turbines and related devices.

  13. Dissecting the pressure field in tidal flow

    E-Print Network [OSTI]

    amplitude [N x 107 ] phase relative to the velocity [deg] power [W x107 ] 1 2 3 4 tidal excursion parameterDissecting the pressure field in tidal flow past a headland: When is form drag "real?" Sally Warner waves eddies H L LHH H L L LH #12;Numerical model Gaussian-shaped headland Barotropic tidal velocity D L

  14. Grid Connectivity Research, Development & Demonstration Projects

    Broader source: Energy.gov [DOE]

    2013 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting

  15. Grid Connected Functionalities | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,Executive CompensationEnergyGetDepartment of|GreenerGrid ApplicationsGrid

  16. General relativistic tidal heating for Moller pseudotensor

    E-Print Network [OSTI]

    Lau Loi So

    2015-09-30

    Thorne elucidated that the relativistic tidal heating is the same as the Newtonian theory. Moreover, Thorne also claimed that the tidal heating is independent of how one localizes gravitational energy and is unambiguously given by a certain formula. Purdue and Favata calculated the tidal heating for different classical pseudotensors including Moller and obtained the results all matched with the Newtonian perspective. After re-examined this Moller pseudotensor, we find that there does not exist any tidal heating value. Thus we claim that the relativistic tidal heating is pseudotensor independent under the condition that if the peusdotensor is a Freud typed superpotential.

  17. General relativistic tidal heating for Moller pseudotensor

    E-Print Network [OSTI]

    So, Lau Loi

    2015-01-01

    Thorne elucidated that the relativistic tidal heating is the same as the Newtonian theory. Moreover, Thorne also claimed that the tidal heating is independent of how one localizes gravitational energy and is unambiguously given by a certain formula. Purdue and Favata calculated the tidal heating for different classical pseudotensors including Moller and obtained the results all matched with the Newtonian perspective. After re-examined this Moller pseudotensor, we find that there does not exist any tidal heating value. Thus we claim that the relativistic tidal heating is pseudotensor independent under the condition that if the peusdotensor is a Freud typed superpotential.

  18. ARRAY OPTIMIZATION FOR TIDAL ENERGY EXTRACTION IN A TIDAL CHANNEL – A NUMERICAL MODELING ANALYSIS

    SciTech Connect (OSTI)

    Yang, Zhaoqing; Wang, Taiping; Copping, Andrea

    2014-04-18

    This paper presents an application of a hydrodynamic model to simulate tidal energy extraction in a tidal dominated estuary in the Pacific Northwest coast. A series of numerical experiments were carried out to simulate tidal energy extraction with different turbine array configurations, including location, spacing and array size. Preliminary model results suggest that array optimization for tidal energy extraction in a real-world site is a very complex process that requires consideration of multiple factors. Numerical models can be used effectively to assist turbine siting and array arrangement in a tidal turbine farm for tidal energy extraction.

  19. Siting Study Framework and Survey Methodology for Marine and Hydrokinetic Energy Project in Offshore Southeast Florida

    SciTech Connect (OSTI)

    Vinick, Charles; Riccobono, Antonino, MS; Messing, Charles G., Ph.D.; Walker, Brian K., Ph.D.; Reed, John K., Ph.D.

    2012-02-28

    Dehlsen Associates, LLC was awarded a grant by the United States Department of Energy (DOE) Golden Field Office for a project titled 'Siting Study Framework and Survey Methodology for Marine and Hydrokinetic Energy Project in Offshore Southeast Florida,' corresponding to DOE Grant Award Number DE-EE0002655 resulting from DOE funding Opportunity Announcement Number DE-FOA-0000069 for Topic Area 2, and it is referred to herein as 'the project.' The purpose of the project was to enhance the certainty of the survey requirements and regulatory review processes for the purpose of reducing the time, efforts, and costs associated with initial siting efforts of marine and hydrokinetic energy conversion facilities that may be proposed in the Atlantic Ocean offshore Southeast Florida. To secure early input from agencies, protocols were developed for collecting baseline geophysical information and benthic habitat data that can be used by project developers and regulators to make decisions early in the process of determining project location (i.e., the siting process) that avoid or minimize adverse impacts to sensitive marine benthic habitat. It is presumed that such an approach will help facilitate the licensing process for hydrokinetic and other ocean renewable energy projects within the study area and will assist in clarifying the baseline environmental data requirements described in the U.S. Department of the Interior Bureau of Ocean Energy Management, Regulation and Enforcement (formerly Minerals Management Service) final regulations on offshore renewable energy (30 Code of Federal Regulations 285, published April 29, 2009). Because projects generally seek to avoid or minimize impacts to sensitive marine habitats, it was not the intent of this project to investigate areas that did not appear suitable for the siting of ocean renewable energy projects. Rather, a two-tiered approach was designed with the first step consisting of gaining overall insight about seabed conditions offshore southeastern Florida by conducting a geophysical survey of pre-selected areas with subsequent post-processing and expert data interpretation by geophysicists and experienced marine biologists knowledgeable about the general project area. The second step sought to validate the benthic habitat types interpreted from the geophysical data by conducting benthic video and photographic field surveys of selected habitat types. The goal of this step was to determine the degree of correlation between the habitat types interpreted from the geophysical data and what actually exists on the seafloor based on the benthic video survey logs. This step included spot-checking selected habitat types rather than comprehensive evaluation of the entire area covered by the geophysical survey. It is important to note that non-invasive survey methods were used as part of this study and no devices of any kind were either temporarily or permanently attached to the seabed as part of the work conducted under this project.

  20. Dynamical modeling of tidal streams

    SciTech Connect (OSTI)

    Bovy, Jo, E-mail: bovy@ias.edu [Institute for Advanced Study, Einstein Drive, Princeton, NJ 08540 (United States)

    2014-11-01

    I present a new framework for modeling the dynamics of tidal streams. The framework consists of simple models for the initial action-angle distribution of tidal debris, which can be straightforwardly evolved forward in time. Taking advantage of the essentially one-dimensional nature of tidal streams, the transformation to position-velocity coordinates can be linearized and interpolated near a small number of points along the stream, thus allowing for efficient computations of a stream's properties in observable quantities. I illustrate how to calculate the stream's average location (its 'track') in different coordinate systems, how to quickly estimate the dispersion around its track, and how to draw mock stream data. As a generative model, this framework allows one to compute the full probability distribution function and marginalize over or condition it on certain phase-space dimensions as well as convolve it with observational uncertainties. This will be instrumental in proper data analysis of stream data. In addition to providing a computationally efficient practical tool for modeling the dynamics of tidal streams, the action-angle nature of the framework helps elucidate how the observed width of the stream relates to the velocity dispersion or mass of the progenitor, and how the progenitors of 'orphan' streams could be located. The practical usefulness of the proposed framework crucially depends on the ability to calculate action-angle variables for any orbit in any gravitational potential. A novel method for calculating actions, frequencies, and angles in any static potential using a single orbit integration is described in the Appendix.

  1. Tidally-induced thermonuclear Supernovae

    E-Print Network [OSTI]

    S. Rosswog; E. Ramirez-Ruiz; W. R. Hix

    2008-11-13

    We discuss the results of 3D simulations of tidal disruptions of white dwarfs by moderate-mass black holes as they may exist in the cores of globular clusters or dwarf galaxies. Our simulations follow self-consistently the hydrodynamic and nuclear evolution from the initial parabolic orbit over the disruption to the build-up of an accretion disk around the black hole. For strong enough encounters (pericentre distances smaller than about 1/3 of the tidal radius) the tidal compression is reversed by a shock and finally results in a thermonuclear explosion. These explosions are not restricted to progenitor masses close to the Chandrasekhar limit, we find exploding examples throughout the whole white dwarf mass range. There is, however, a restriction on the masses of the involved black holes: black holes more massive than $2\\times 10^5$ M$_\\odot$ swallow a typical 0.6 M$_\\odot$ dwarf before their tidal forces can overwhelm the star's self-gravity. Therefore, this mechanism is characteristic for black holes of moderate masses. The material that remains bound to the black hole settles into an accretion disk and produces an X-ray flare close to the Eddington limit of $L_{\\rm Edd} \\simeq 10^{41} {\\rm erg/s} M_{\\rm bh}/1000 M$_\\odot$), typically lasting for a few months. The combination of a peculiar thermonuclear supernova together with an X-ray flare thus whistle-blows the existence of such moderate-mass black holes. The next generation of wide field space-based instruments should be able to detect such events.

  2. Environmentally Benign and Permanent Modifications to Prevent Biofouling on Marine and Hydrokinetic Devices

    SciTech Connect (OSTI)

    Zheng Zhang

    2012-04-19

    Semprus Biosciences is developing environmentally benign and permanent modifications to prevent biofouling on Marine and Hydrokinetic (MHK) devices. Biofouling, including growth on external surfaces by bacteria, algae, barnacles, mussels, and other marine organisms, accumulate quickly on MHK devices, causing mechanical wear and changes in performance. Biofouling on crucial components of hydrokinetic devices, such as rotors, generators, and turbines, imposes substantial mass and hydrodynamic loading with associated efficiency loss and maintenance costs. Most antifouling coatings leach toxic ingredients, such as copper and tributyltin, through an eroding process, but increasingly stringent regulation of biocides has led to interest in the development of non-biocidal technologies to control fouling. Semprus Biosciences research team is developing modifications to prevent fouling from a broad spectrum of organisms on devices of all shapes, sizes, and materials for the life of the product. The research team designed and developed betaine-based polymers as novel underwater coatings to resist the attachment of marine organisms. Different betaine-based monomers and polymers were synthesized and incorporated within various coating formulations. The formulations and application methods were developed on aluminum panels with required adhesion strength and mechanical properties. The coating polymers were chemically stable under UV, hydrolytic and oxidative environments. The sulfobetaine formulations are applicable as nonleaching and stable underwater coatings. For the first time, coating formulations modified with highly packed sulfobetaine polymers were prepared and demonstrated resistance to a broad spectrum of marine organisms. Assays for comparing nonfouling performance were developed to evaluate protein adsorption and bacteria attachment. Barnacle settlement and removal were evaluated and a 60-day field test was performed. Silicone substrates including a commercial fouling release coating were used for comparison. Compared with the unmodified silicone substrates, the sulfobetaine-modified formulations were able to exhibit a 98% reduction in fibrinogen adsorption, 97.0% (E. coli), 99.6% (S. aureus), and 99.5% (C. lytica) reduction in bacteria attachment, and 100% reduction in barnacles cyprid attachment. In addition to the significant improvement in fouling resistance of various organisms, the 60-day field test also showed an evident efficacy from visual assessment, foul rating, and fouling removal test. The research confirmed that the novel antifouling mechanism of betaine polymers provides a new avenue for marine coating development. The developed coatings out-performed currently used nontoxic underwater coatings in a broad spectrum of fouling resistance. By further developing formulations and processing methods for specific devices, the technology is ready for the next stage of development with demonstration in MHK systems.

  3. TIDAL NOVAE IN COMPACT BINARY WHITE DWARFS

    SciTech Connect (OSTI)

    Fuller, Jim; Lai Dong [Department of Astronomy, Cornell University, Ithaca, NY 14850 (United States)

    2012-09-01

    Compact binary white dwarfs (WDs) undergoing orbital decay due to gravitational radiation can experience significant tidal heating prior to merger. In these WDs, the dominant tidal effect involves the excitation of outgoing gravity waves in the inner stellar envelope and the dissipation of these waves in the outer envelope. As the binary orbit decays, the WDs are synchronized from outside in (with the envelope synchronized first, followed by the core). We examine the deposition of tidal heat in the envelope of a carbon-oxygen WD and study how such tidal heating affects the structure and evolution of the WD. We show that significant tidal heating can occur in the star's degenerate hydrogen layer. This layer heats up faster than it cools, triggering runaway nuclear fusion. Such 'tidal novae' may occur in all WD binaries containing a CO WD, at orbital periods between 5 minutes and 20 minutes, and precede the final merger by 10{sup 5}-10{sup 6} years.

  4. Marine and Hydrokinetic Technology (MHK) Instrumentation, Measurement, and Computer Modeling Workshop

    SciTech Connect (OSTI)

    Musial, W.; Lawson, M.; Rooney, S.

    2013-02-01

    The Marine and Hydrokinetic Technology (MHK) Instrumentation, Measurement, and Computer Modeling Workshop was hosted by the National Renewable Energy Laboratory (NREL) in Broomfield, Colorado, July 9-10, 2012. The workshop brought together over 60 experts in marine energy technologies to disseminate technical information to the marine energy community and collect information to help identify ways in which the development of a commercially viable marine energy industry can be accelerated. The workshop was comprised of plenary sessions that reviewed the state of the marine energy industry and technical sessions that covered specific topics of relevance. Each session consisted of presentations, followed by facilitated discussions. During the facilitated discussions, the session chairs posed several prepared questions to the presenters and audience to encourage communication and the exchange of ideas between technical experts. Following the workshop, attendees were asked to provide written feedback on their takeaways and their best ideas on how to accelerate the pace of marine energy technology development. The first four sections of this document give a general overview of the workshop format, provide presentation abstracts and discussion session notes, and list responses to the post-workshop questions. The final section presents key findings and conclusions from the workshop that suggest how the U.S. Department of Energy and national laboratory resources can be utilized to most effectively assist the marine energy industry.

  5. Identification and Prioritization of Analysis Cases for Marine and Hydrokinetic Energy Risk Screening

    SciTech Connect (OSTI)

    Anderson, Richard M.; Unwin, Stephen D.; Van Cleve, Frances B.

    2010-06-16

    In this report we describe the development of the Environmental Risk Evaluation System (ERES), a risk-informed analytical process for estimating the environmental risks associated with the construction and operation of marine and hydrokinetic energy generation projects. The development process consists of two main phases of analysis. In the first phase, preliminary risk analyses will take the form of screening studies in which key environmental impacts and the uncertainties that create risk are identified, leading to a better-focused characterization of the relevant environmental effects. Existence of critical data gaps will suggest areas in which specific modeling and/or data collection activities should take place. In the second phase, more detailed quantitative risk analyses will be conducted, with residual uncertainties providing the basis for recommending risk mitigation and monitoring activities. We also describe the process used for selecting three cases for fiscal year 2010 risk screening analysis using the ERES. A case is defined as a specific technology deployed in a particular location involving certain environmental receptors specific to that location. The three cases selected satisfy a number of desirable criteria: 1) they correspond to real projects whose deployment is likely to take place in the foreseeable future; 2) the technology developers are willing to share technology and project-related data; 3) the projects represent a diversity of technology-site-receptor characteristics; 4) the projects are of national interest, and 5) environmental effects data may be available for the projects.

  6. Sandia National Laboratories environmental fluid dynamics code. Marine Hydrokinetic Module User's Manual

    SciTech Connect (OSTI)

    James, Scott Carlton; Roberts, Jesse D.

    2014-03-01

    This document describes the marine hydrokinetic (MHK) input file and subroutines for the Sandia National Laboratories Environmental Fluid Dynamics Code (SNL-EFDC), which is a combined hydrodynamic, sediment transport, and water quality model based on the Environmental Fluid Dynamics Code (EFDC) developed by John Hamrick [1], formerly sponsored by the U.S. Environmental Protection Agency, and now maintained by Tetra Tech, Inc. SNL-EFDC has been previously enhanced with the incorporation of the SEDZLJ sediment dynamics model developed by Ziegler, Lick, and Jones [2-4]. SNL-EFDC has also been upgraded to more accurately simulate algae growth with specific application to optimizing biomass in an open-channel raceway for biofuels production [5]. A detailed description of the input file containing data describing the MHK device/array is provided, along with a description of the MHK FORTRAN routine. Both a theoretical description of the MHK dynamics as incorporated into SNL-EFDC and an explanation of the source code are provided. This user manual is meant to be used in conjunction with the original EFDC [6] and sediment dynamics SNL-EFDC manuals [7]. Through this document, the authors provide information for users who wish to model the effects of an MHK device (or array of devices) on a flow system with EFDC and who also seek a clear understanding of the source code, which is available from staff in the Water Power Technologies Department at Sandia National Laboratories, Albuquerque, New Mexico.

  7. Marine and Hydrokinetic Technology (MHK) Instrumentation, Measurement, and Computer Modeling Workshop

    SciTech Connect (OSTI)

    Musial, W.; Lawson, M.; Rooney, S.

    2013-02-01

    The Marine and Hydrokinetic Technology (MHK) Instrumentation, Measurement, and Computer Modeling Workshop was hosted by the National Renewable Energy Laboratory (NREL) in Broomfield, Colorado, July 9–10, 2012. The workshop brought together over 60 experts in marine energy technologies to disseminate technical information to the marine energy community, and to collect information to help identify ways in which the development of a commercially viable marine energy industry can be accelerated. The workshop was comprised of plenary sessions that reviewed the state of the marine energy industry and technical sessions that covered specific topics of relevance. Each session consisted of presentations, followed by facilitated discussions. During the facilitated discussions, the session chairs posed several prepared questions to the presenters and audience to encourage communication and the exchange of ideas between technical experts. Following the workshop, attendees were asked to provide written feedback on their takeaways from the workshop and their best ideas on how to accelerate the pace of marine energy technology development. The first four sections of this document give a general overview of the workshop format, provide presentation abstracts, supply discussion session notes, and list responses to the post-workshop questions. The final section presents key findings and conclusions from the workshop that suggest what the most pressing MHK technology needs are and how the U.S. Department of Energy (DOE) and national laboratory resources can be utilized to assist the marine energy industry in the most effective manner.

  8. Tidal Electric | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-EnhancingEt Al., 2013)Open Energy Information ThreeTianDi GrowthTibagiTidal

  9. Turbulence and internal waves in tidal flow over topography

    E-Print Network [OSTI]

    Gayen, Bishakhdatta

    2012-01-01

    M. C. 2006 An estimate of tidal energy lost to turbulence atcant loss of low-mode tidal energy at 28.9 ? . Geophys. Res.of turbulent kinetic energy over a tidal cycle. Maximum T KE

  10. Dispersion and Tidal Dynamics of Channel-Shoal Estuaries

    E-Print Network [OSTI]

    Holleman, Christopher Dean

    2013-01-01

    San Pablo Bay: ? M 2 and tidal energy flux for the hNS0? M 2 and tidal energy flux for hNS0. . . . . . . . . . .areas dissipate incident tidal energy, countering the added

  11. Sandia Energy - Tidal & Current Modeling Development and Validation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Tidal & Current Modeling Development and Validation Home Stationary Power Energy Conversion Efficiency Water Power Technology Development Tidal & Current Modeling Development and...

  12. Tidal deformations of a spinning compact object

    E-Print Network [OSTI]

    Pani, Paolo; Maselli, Andrea; Ferrari, Valeria

    2015-01-01

    The deformability of a compact object induced by a perturbing tidal field is encoded in the tidal Love numbers, which depend sensibly on the object's internal structure. These numbers are known only for static, spherically-symmetric objects. As a first step to compute the tidal Love numbers of a spinning compact star, here we extend powerful perturbative techniques to compute the exterior geometry of a spinning object distorted by an axisymmetric tidal field to second order in the angular momentum. The spin of the object introduces couplings between electric and magnetic deformations and new classes of induced Love numbers emerge. For example, a spinning object immersed in a quadrupolar, electric tidal field can acquire some induced mass, spin, quadrupole, octupole and hexadecapole moments to second order in the spin. The deformations are encoded in a set of inhomogeneous differential equations which, remarkably, can be solved analytically in vacuum. We discuss certain subtleties in defining the multipole mom...

  13. Tidal deformations of a spinning compact object

    E-Print Network [OSTI]

    Paolo Pani; Leonardo Gualtieri; Andrea Maselli; Valeria Ferrari

    2015-06-30

    The deformability of a compact object induced by a perturbing tidal field is encoded in the tidal Love numbers, which depend sensibly on the object's internal structure. These numbers are known only for static, spherically-symmetric objects. As a first step to compute the tidal Love numbers of a spinning compact star, here we extend powerful perturbative techniques to compute the exterior geometry of a spinning object distorted by an axisymmetric tidal field to second order in the angular momentum. The spin of the object introduces couplings between electric and magnetic deformations and new classes of induced Love numbers emerge. For example, a spinning object immersed in a quadrupolar, electric tidal field can acquire some induced mass, spin, quadrupole, octupole and hexadecapole moments to second order in the spin. The deformations are encoded in a set of inhomogeneous differential equations which, remarkably, can be solved analytically in vacuum. We discuss certain subtleties in defining the multipole moments of the central object, which are due to the difficulty in separating the tidal field from the linear response of the object in the solution. By extending the standard procedure to identify the linear response in the static case, we prove analytically that the Love numbers of a Kerr black hole remain zero to second order in the spin. As a by-product, we provide the explicit form for a slowly-rotating, tidally-deformed Kerr black hole to quadratic order in the spin, and discuss its geodesic and geometrical properties.

  14. 12th Annual Wave & Tidal 2015

    Broader source: Energy.gov [DOE]

    The UK is currently the undisputed global leader in marine energy, with more wave and tidal stream devices installed than the rest of the world combined. This leading position is built on an...

  15. Evaluation of behaviour and survival of fish exposed to an axial-flow hydrokinetic turbine

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Amaral, Stephen; Bevelhimer, Mark S; Cada, Glenn F; Giza, Daniel; Jacobsen, Paul; McMahon, Brian; Pracheil, Brenda M

    2015-01-01

    Previous studies have evaluated fish injury and mortality at hydrokinetic (HK) turbines, but because these studies focused on the impacts of these turbines in situ they were unable to evaluate fish responses to controlled environmental characteristics (e.g., current velocity and light or dark conditions). In this study, we used juvenile hybrid Striped Bass (HSB; Striped Bass Morone saxatilis White Bass M. chrysops; N D 620), Rainbow Trout Oncorhynchus mykiss (N D 3,719), and White Sturgeon Acipenser transmontanus (N D 294) in a series of laboratory experiments to (1) evaluate the ability of fish to avoid entrainment through an axial-flow HKmore »turbine, (2) evaluate fish injury and survival associated with turbine entrainment, and (3) compare the effects of different HK turbines on fish. We found that the probability of turbine entrainment was species dependent and highest for HSB. Across species, current velocity influenced entrainment probability. Among entrained fish, observed survival rates were generally >0.95. The probability of injury for surviving entrained fish only differed from that for nonentrained fish for Rainbow Trout and in general was not >0.20. The probability of injury following entrainment was greater only for HSB, although there were no differences in injury rates between fish that were turbine entrained and those that were not, suggesting that injuries were not turbine related. Taking turbine entrainment, survival, and injury estimates together allowed us to estimate the probability of a randomly selected fish in a population proximate to an HK turbine surviving passage or remaining uninjured after passage. For species and current velocities for which there was a significant effect due to entrainment, we estimated, for instance, that HSB had a survival probability of 0.95 and that Rainbow Trout and White Sturgeon had a >0.99 probability of survival. Similarly, by combining these estimates with those from previous studies, we derived total passage survival probabilities >0.90 but generally approaching 1.00 across different HK turbine types, fish species, and fish lengths.« less

  16. Evaluation of behavior and survival of fish exposed to an axial-flow hydrokinetic turbine

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Amaral, Stephen V.; Bevelhimer, Mark S.; ?ada, Glenn F.; Giza, Daniel J.; Jacobson, Paul T.; McMahon, Brian J.; Pracheil, Brenda M.

    2015-02-06

    Previous studies have evaluated fish injury and mortality at hydrokinetic (HK) turbines, but because these studies focused on the impacts of these turbines in situ they were unable to evaluate fish responses to controlled environmental characteristics (e.g., current velocity and light or dark conditions). In this study, we used juvenile hybrid Striped Bass (HSB; Striped Bass Morone saxatilis White Bass M. chrysops; N D 620), Rainbow Trout Oncorhynchus mykiss (N D 3,719), and White Sturgeon Acipenser transmontanus (N D 294) in a series of laboratory experiments to (1) evaluate the ability of fish to avoid entrainment through an axial-flow HKmore »turbine, (2) evaluate fish injury and survival associated with turbine entrainment, and (3) compare the effects of different HK turbines on fish. We found that the probability of turbine entrainment was species dependent and highest for HSB. Across species, current velocity influenced entrainment probability. Among entrained fish, observed survival rates were generally >0.95. The probability of injury for surviving entrained fish only differed from that for nonentrained fish for Rainbow Trout and in general was not >0.20. The probability of injury following entrainment was greater only for HSB, although there were no differences in injury rates between fish that were turbine entrained and those that were not, suggesting that injuries were not turbine related. Taking turbine entrainment, survival, and injury estimates together allowed us to estimate the probability of a randomly selected fish in a population proximate to an HK turbine surviving passage or remaining uninjured after passage. For species and current velocities for which there was a significant effect due to entrainment, we estimated, for instance, that HSB had a survival probability of 0.95 and that Rainbow Trout and White Sturgeon had a >0.99 probability of survival. By combining these estimates with those from previous studies, we derived total passage survival probabilities >0.90 but generally approaching 1.00 across different HK turbine types, fish species, and fish lengths.« less

  17. Assssment and Mapping of the Riverine Hydrokinetic Resource in the Continental United States

    SciTech Connect (OSTI)

    Jacobson, Paul T.; Ravens, Thomas M.; Cunningham, Keith W.; Scott, George

    2012-12-14

    The U.S. Department of Energy (DOE) funded the Electric Power Research Institute and its collaborative partners, University of Alaska ? Anchorage, University of Alaska ? Fairbanks, and the National Renewable Energy Laboratory, to provide an assessment of the riverine hydrokinetic resource in the continental United States. The assessment benefited from input obtained during two workshops attended by individuals with relevant expertise and from a National Research Council panel commissioned by DOE to provide guidance to this and other concurrent, DOE-funded assessments of water based renewable energy. These sources of expertise provided valuable advice regarding data sources and assessment methodology. The assessment of the hydrokinetic resource in the 48 contiguous states is derived from spatially-explicit data contained in NHDPlus ?a GIS-based database containing river segment-specific information on discharge characteristics and channel slope. 71,398 river segments with mean annual flow greater than 1,000 cubic feet per second (cfs) mean discharge were included in the assessment. Segments with discharge less than 1,000 cfs were dropped from the assessment, as were river segments with hydroelectric dams. The results for the theoretical and technical resource in the 48 contiguous states were found to be relatively insensitive to the cutoff chosen. Raising the cutoff to 1,500 cfs had no effect on estimate of the technically recoverable resource, and the theoretical resource was reduced by 5.3%. The segment-specific theoretical resource was estimated from these data using the standard hydrological engineering equation that relates theoretical hydraulic power (Pth, Watts) to discharge (Q, m3 s-1) and hydraulic head or change in elevation (??, m) over the length of the segment, where ? is the specific weight of water (9800 N m-3): ??? = ? ? ?? For Alaska, which is not encompassed by NPDPlus, hydraulic head and discharge data were manually obtained from Idaho National Laboratory?s Virtual Hydropower Prospector, Google Earth, and U.S. Geological Survey gages. Data were manually obtained for the eleven largest rivers with average flow rates greater than 10,000 cfs and the resulting estimate of the theoretical resource was expanded to include rivers with discharge between 1,000 cfs and 10,000 cfs based upon the contribution of rivers in the latter flow class to the total estimate in the contiguous 48 states. Segment-specific theoretical resource was aggregated by major hydrologic region in the contiguous, lower 48 states and totaled 1,146 TWh/yr. The aggregate estimate of the Alaska theoretical resource is 235 TWh/yr, yielding a total theoretical resource estimate of 1,381 TWh/yr for the continental US. The technically recoverable resource in the contiguous 48 states was estimated by applying a recovery factor to the segment-specific theoretical resource estimates. The recovery factor scales the theoretical resource for a given segment to take into account assumptions such as minimum required water velocity and depth during low flow conditions, maximum device packing density, device efficiency, and flow statistics (e.g., the 5 percentile flow relative to the average flow rate). The recovery factor also takes account of ?back effects? ? feedback effects of turbine presence on hydraulic head and velocity. The recovery factor was determined over a range of flow rates and slopes using the hydraulic model, HEC-RAS. In the hydraulic modeling, presence of turbines was accounted for by adjusting the Manning coefficient. This analysis, which included 32 scenarios, led to an empirical function relating recovery factor to slope and discharge. Sixty-nine percent of NHDPlus segments included in the theoretical resource estimate for the contiguous 48 states had an estimated recovery factor of zero. For Alaska, data on river slope was not readily available; hence, the recovery factor was estimated based on the flow rate alone. Segment-specific estimates of the theoretical resource were multiplied by the corresponding recovery factor to estimate

  18. Marine Hydrokinetic Turbine Power-Take-Off Design for Optimal Performance and Low Impact on Cost-of-Energy: Preprint

    SciTech Connect (OSTI)

    Beam, M.; Kline, B.; Elbing, B.; Straka, W.; Fontaine, A.; Lawson, M.; Li, Y.; Thresher, R.; Previsic, M.

    2012-04-01

    Marine hydrokinetic devices are becoming a popular method for generating marine renewable energy worldwide. These devices generate electricity by converting the kinetic energy of moving water, wave motion or currents, into electrical energy through the use of a Power-Take-Off (PTO) system. Most PTO systems incorporate a mechanical or hydraulic drive train, power generator and electric control/conditioning system to deliver the generated electric power to the grid at the required state. Like wind turbine applications, the PTO system must be designed for high reliability, good efficiency, and long service life with reasonable maintenance requirements, low cost and an appropriate mechanical design for anticipated applied steady and unsteady loads. The ultimate goal of a PTO design is high efficiency, low maintenance and cost with a low impact on the device Cost-of-Energy (CoE).

  19. Marine Hydrokinetic Turbine Power-Take-Off Design for Optimal Performance and Low Impact on Cost-of-Energy: Preprint

    SciTech Connect (OSTI)

    Beam, M.; Kline, B.; Elbing, B.; Straka, W.; Fontaine, A.; Lawson, M.; Li, Y.; Thresher, R.; Previsic, M.

    2013-02-01

    Marine hydrokinetic devices are becoming a popular method for generating marine renewable energy worldwide. These devices generate electricity by converting the kinetic energy of moving water, wave motion or currents, into electrical energy through the use of a power-take-off (PTO) system. Most PTO systems incorporate a mechanical or hydraulic drivetrain, power generator, and electric control/conditioning system to deliver the generated electric power to the grid at the required state. Like wind turbine applications, the PTO system must be designed for high reliability, good efficiency, and long service life with reasonable maintenance requirements, low cost, and an appropriate mechanical design for anticipated applied steady and unsteady loads. The ultimate goal of a PTO design is high efficiency and low maintenance and cost, with a low impact on the device cost-of-energy (CoE).

  20. Sandia Energy - EC Publications

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Test Plan - DOE Tidal And River Reference Turbines (40) Field Measurements at River and Tidal Current Sites for Hydrokinetic Energy Development: Best Practices Manual (40)...

  1. Tidal Forces in Naked Singularity Backgrounds

    E-Print Network [OSTI]

    Goel, Akash; Roy, Pratim; Sarkar, Tapobrata

    2015-01-01

    The end stage of a gravitational collapse process can generically result in a black hole or a naked singularity. Here we undertake a comparative analysis of the nature of tidal forces in these backgrounds. The effect of such forces is generically exemplified by the Roche limit, which predicts the distance within which a celestial object disintegrates due to the tidal effects of a second more massive object. In this paper, using Fermi normal coordinates, we numerically compute the Roche limit for a class of non-rotating naked singularity backgrounds, and compare them with known results for Schwarzschild black holes. Our analysis indicates that there might be substantially large deviations in the magnitudes of tidal forces in naked singularity backgrounds, compared to the black hole cases. If observationally established, these can prove to be an effective indicator of the nature of the singularity at a galactic centre.

  2. TIDAL TURBULENCE SPECTRA FROM A COMPLIANT MOORING

    SciTech Connect (OSTI)

    Thomson, Jim; Kilcher, Levi; Richmond, Marshall C.; Talbert, Joe; deKlerk, Alex; Polagye, Brian; Guerra, Maricarmen; Cienfuegos, Rodrigo

    2013-06-13

    A compliant mooring to collect high frequency turbulence data at a tidal energy site is evaluated in a series of short demon- stration deployments. The Tidal Turbulence Mooring (TTM) improves upon recent bottom-mounted approaches by suspend- ing Acoustic Doppler Velocimeters (ADVs) at mid-water depths (which are more relevant to tidal turbines). The ADV turbulence data are superior to Acoustic Doppler Current Profiler (ADCP) data, but are subject to motion contamination when suspended on a mooring in strong currents. In this demonstration, passive stabilization is shown to be sufficient for acquiring bulk statistics of the turbulence, without motion correction. With motion cor- rection (post-processing), data quality is further improved; the relative merits of direct and spectral motion correction are dis- cussed.

  3. Tidal analysis of water level in continental boreholes Version 2.2

    E-Print Network [OSTI]

    Brodsky, Emily

    tidal analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 4.3.1 The "credo

  4. Assessment of Energy Production Potential from Tidal Streams...

    Broader source: Energy.gov (indexed) [DOE]

    project documented in this report created a national database of tidal stream energy potential, as well as a GIS tool usable by industry in order to accelerate the market for tidal...

  5. The rotation and fracture history of Europa from modeling of tidal-tectonic processes

    E-Print Network [OSTI]

    Rhoden, Alyssa Rose

    2011-01-01

    the tidal stresses. They adopted a power-law viscoelasticpower of the model. However, the mechanics of tidal walking

  6. Screening Analysis for the Environmental Risk Evaluation System Task 2.1.1.2: Evaluating Effects of Stressors Fiscal Year 2011 Progress Report - Environmental Effects of Marine and Hydrokinetic Energy

    SciTech Connect (OSTI)

    Copping, Andrea E.; Blake, Kara M.; Anderson, Richard M.; Zdanski, Laura C.; Gill, Gary A.; Ward, Jeffrey A.

    2011-09-01

    Potential environmental effects of marine and hydrokinetic (MHK) energy development are not well understood, and yet regulatory agencies are required to make decisions in spite of substantial uncertainty about environmental impacts and their long-term consequences. An understanding of risks associated with interactions between MHK installations and aquatic receptors, including animals, habitats, and ecosystems, can help define key uncertainties and focus regulatory actions and scientific studies on interactions of most concern. As a first step in developing the Pacific Northwest National Laboratory (PNNL) Environmental Risk Evaluation System (ERES), PNNL scientists conducted a preliminary risk screening analysis on three initial MHK cases. During FY 2011, two additional cases were added: a tidal project in the Gulf of Maine using Ocean Renewable Power Company TidGenTM turbines and a wave project planned for the coast of Oregon using Aquamarine Oyster surge devices. Through an iterative process, the screening analysis revealed that top-tier stressors in the two FY 2011 cases were the dynamic effects of the device (e.g., strike), accidents/disasters, and effects of the static physical presence of the device (e.g., habitat alteration). Receptor interactions with these stressors at the highest tiers of risk were dominated by threatened and endangered animals. Risk to the physical environment from changes in flow regime also ranked high. Peer review of this process and results will be conducted in early FY 2012. The ERES screening analysis provides an analysis of vulnerability of environmental receptors to stressors associated with MHK installations, probability analysis is needed to determine specific risk levels to receptors. “Risk” has two components: (1) The likelihood, or “probability”, of the occurrence of a given interaction or event, and (2) the potential “consequence” if that interaction or event were to occur. During FY 2011, the ERES screening analysis focused primarily on the second component of risk, “consequence”, with focused probability analysis for interactions where data was sufficient for probability modeling. Consequence analysis provides an assessment of vulnerability of environmental receptors to stressors associated with MHK installations. Probability analysis is needed to determine specific risk levels to receptors and requires significant data inputs to drive risk models. During FY 2011, two stressor-receptor interactions were examined for the probability of occurrence. The two interactions (spill probability due to an encounter between a surface vessel and an MHK device; and toxicity from anti-biofouling paints on MHK devices) were seen to present relatively low risks to marine and freshwater receptors of greatest concern in siting and permitting MHK devices. A third probability analysis was scoped and initial steps taken to understand the risk of encounter between marine animals and rotating turbine blades. This analysis will be completed in FY 2012.

  7. Tidal networks 2. Watershed delineation and comparative network morphology

    E-Print Network [OSTI]

    Fagherazzi, Sergio

    of three, we quantify various tidal network properties including common power law relationships which have common power law relationships quantified for terrestrial systems to tidal systems and use these analysesTidal networks 2. Watershed delineation and comparative network morphology Andrea Rinaldo,1 Sergio

  8. Enhancing Electrical Supply by Pumped Storage in Tidal Lagoons

    E-Print Network [OSTI]

    MacKay, David J.C.

    to demand into high­value demand­following power; and second, it can simultaneously serve as a tidal powerEnhancing Electrical Supply by Pumped Storage in Tidal Lagoons David J.C. MacKay Cavendish/3/07 Summary The principle that the net energy delivered by a tidal pool can be increased by pumping extra

  9. Tidal networks 3. Landscape-forming discharges and studies

    E-Print Network [OSTI]

    Fagherazzi, Sergio

    Tidal networks 3. Landscape-forming discharges and studies in empirical geomorphic relationships peak ebb and flood discharges throughout a tidal network and use this model to investigate scaling flows are driven by spring (astronomical) tidal fluctuations (rather than precipitation- induced runoff

  10. Rotational stability of tidally deformed planetary I. Matsuyama1

    E-Print Network [OSTI]

    Nimmo, Francis

    Rotational stability of tidally deformed planetary bodies I. Matsuyama1 and F. Nimmo2 Received 11 consider the true polar wander (rotational variations driven by mass redistribution) of tidally deformed planetary bodies. The rotation pole of bodies without tidal deformation is stabilized by the component

  11. Research papers Tidal characteristics of the gulf of Tonkin

    E-Print Network [OSTI]

    calibration derived from a set of sensitivity experiments to model parameters. The tidal energy budgetResearch papers Tidal characteristics of the gulf of Tonkin Nguyen Nguyet Minh a,c , Marchesiello of this study is to revisit the dominant physical processes that characterize tidal dynamics in the Gulf

  12. TIDAL FRESHWATER WETLANDS OF THE MID-ATLANTIC AND

    E-Print Network [OSTI]

    Fabrizio, Mary C.

    Chapter 14 TIDAL FRESHWATER WETLANDS OF THE MID-ATLANTIC AND SOUTHEASTERN UNITED STATES James E Jensen& Aat Barendregt 7. Animal communities in North American tidal fresh- water wetlands Christopher W Struyf, Tom Maris, Tom Cox & Patrick Meire 12. Carbon flows, nutrient cycling, and food webs in tidal

  13. Assessment of Tidal Energy Removal Impacts on Physical Systems: Development of MHK Module and Analysis of Effects on Hydrodynamics

    SciTech Connect (OSTI)

    Yang, Zhaoqing; Wang, Taiping

    2011-09-01

    In this report we describe (1) the development, test, and validation of the marine hydrokinetic energy scheme in a three-dimensional coastal ocean model (FVCOM); and (2) the sensitivity analysis of effects of marine hydrokinetic energy configurations on power extraction and volume flux in a coastal bay. Submittal of this report completes the work on Task 2.1.2, Effects of Physical Systems, Subtask 2.1.2.1, Hydrodynamics and Subtask 2.1.2.3, Screening Analysis, for fiscal year 2011 of the Environmental Effects of Marine and Hydrokinetic Energy project.

  14. Dissecting the pressure field in tidal flow

    E-Print Network [OSTI]

    Dissecting the pressure field in tidal flow past a headland: When is form drag "real?" Sally Warner of oscillating flow H L HL velocity form drag power average power floodslack work done on system #12;0 0 0 0 90 180 270 360 90 180 270 360 0 degrees Drag of oscillating flow H L HL velocity form drag power average

  15. FINAL TECHNICAL REPORT: Underwater Active Acoustic Monitoring Network For Marine And Hydrokinetic Energy Projects

    SciTech Connect (OSTI)

    Stein, Peter J.; Edson, Patrick L.

    2013-12-20

    This project saw the completion of the design and development of a second generation, high frequency (90-120 kHz) Subsurface-Threat Detection Sonar Network (SDSN). The system was deployed, operated, and tested in Cobscook Bay, Maine near the site the Ocean Renewable Power Company TidGen™ power unit. This effort resulted in a very successful demonstration of the SDSN detection, tracking, localization, and classification capabilities in a high current, MHK environment as measured by results from the detection and tracking trials in Cobscook Bay. The new high frequency node, designed to operate outside the hearing range of a subset of marine mammals, was shown to detect and track objects of marine mammal-like target strength to ranges of approximately 500 meters. This performance range results in the SDSN system tracking objects for a significant duration - on the order of minutes - even in a tidal flow of 5-7 knots, potentially allowing time for MHK system or operator decision-making if marine mammals are present. Having demonstrated detection and tracking of synthetic targets with target strengths similar to some marine mammals, the primary hurdle to eventual automated monitoring is a dataset of actual marine mammal kinematic behavior and modifying the tracking algorithms and parameters which are currently tuned to human diver kinematics and classification.

  16. Tidal heating in multilayered terrestrial exoplanets

    SciTech Connect (OSTI)

    Henning, Wade G.; Hurford, Terry

    2014-07-01

    The internal pattern and overall magnitude of tidal heating for spin-synchronous terrestrial exoplanets from 1 to 2.5 R{sub E} is investigated using a propagator matrix method for a variety of layer structures. Particular attention is paid to ice-silicate hybrid super-Earths, where a significant ice mantle is modeled to rest atop an iron-silicate core, and may or may not contain a liquid water ocean. We find multilayer modeling often increases tidal dissipation relative to a homogeneous model, across multiple orbital periods, due to the ability to include smaller volume low viscosity regions, and the added flexure allowed by liquid layers. Gradations in parameters with depth are explored, such as allowed by the Preliminary Earth Reference Model. For ice-silicate hybrid worlds, dramatically greater dissipation is possible beyond the case of a silicate mantle only, allowing non-negligible tidal activity to extend to greater orbital periods than previously predicted. Surface patterns of tidal heating are found to potentially be useful for distinguishing internal structure. The influence of ice mantle depth and water ocean size and position are shown for a range of forcing frequencies. Rates of orbital circularization are found to be 10-100 times faster than standard predictions for Earth-analog planets when interiors are moderately warmer than the modern Earth, as well as for a diverse range of ice-silicate hybrid super-Earths. Circularization rates are shown to be significantly longer for planets with layers equivalent to an ocean-free modern Earth, as well as for planets with high fractions of either ice or silicate melting.

  17. Tidal Energy Resource Assessment | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCEDInstallers/ContractorsPhotovoltaicsState ofSavings for Specific2HeldTidal Energy Resource

  18. Reference Model #1 - Tidal Energy: Resource Dr. Brian Polagye

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    constituents, as well as the aharmonic response to these currents induced by local topography and bathymetry. Aharmonic currents are not described by tidal constituents, but are...

  19. Regulatory Assistance, Stakeholder Outreach, and Coastal and Marine Spatial Planning Activities in Support of Marine and Hydrokinetic Energy Deployment

    SciTech Connect (OSTI)

    Geerlofs, Simon H.; Copping, Andrea E.; Van Cleve, Frances B.; Blake, Kara M.; Hanna, Luke A.

    2011-09-30

    This fiscal year 2011 progress report summarizes activities carried out under DOE Water Power Task 2.1.7, Permitting and Planning. Activities under Task 2.1.7 address the concerns of a wide range of stakeholders with an interest in the development of the marine and hydrokinetic (MHK) energy industry, including regulatory and resource management agencies, tribes, nongovernmental organizations, and industry. Objectives for Task 2.1.7 are the following: • to work with stakeholders to streamline the MHK regulatory permitting process • to work with stakeholders to gather information on needs and priorities for environmental assessment of MHK development • to communicate research findings and directions to the MHK industry and stakeholders • to engage in spatial planning processes in order to further the development of the MHK industry. These objectives are met through three subtasks, each of which is described in this report: • 2.1.7.1—Regulatory Assistance • 2.1.7.2—Stakeholder Outreach • 2.1.7.3—Coastal and Marine Spatial Planning. As MHK industry partners work with the regulatory community and stakeholders to plan, site, permit, and license MHK technologies, they have an interest in a predictable, efficient, and transparent process. Stakeholders and regulators have an interest in processes that result in sustainable use of ocean space with minimal effects to existing ocean users. Both stakeholders and regulators have an interest in avoiding legal challenges by meeting the intent of federal, state, and local laws that govern siting and operation of MHK technologies. The intention of work under Task 2.1.7 is to understand and work to address these varied interests, reduce conflict, identify efficiencies, and ultimately reduce the regulatory costs, time, and potential environmental impacts associated with developing, siting, permitting, and deploying MHK systems.

  20. Investigation of Tidal Exchange and the Formation of Tidal Vortices at Aransas Pass, Texas, USA 

    E-Print Network [OSTI]

    Whilden, Kerri Ann

    2015-08-11

    Laboratory and field measurements are presented as part of a study of tidal exchange through Aransas Pass, Texas. At the mouth of Aransas Pass, the input of circulation by the ebb tide forces the formation of a starting-jet dipole vortex...

  1. The importance of tidal creek ecosystems Keywords: Estuary; Tidal creek; Pollution

    E-Print Network [OSTI]

    Mallin, Michael

    . They are most abundant along the Atlantic Seaboard from New Jersey to Florida, and along the Gulf Coast). Tidal creeks are especially abundant in low-energy systems such as protected areas behind barrier. As an example, the four southernmost coastal counties in North Carolina (Onslow, Pender, New Hanover

  2. Tidal Energy Test Platform | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-EnhancingEt Al., 2013)Open Energy Information ThreeTianDi GrowthTibagiTidalTest

  3. Wind and tidal response of a semi-enclosed bay, Bahía Concepción, Baja California

    E-Print Network [OSTI]

    Ponte, Aurélien L. S.

    2009-01-01

    J. H. , 1973: Tidal patterns and energy balance in the GulfTable 4.1). Because the tidal energy is similar between boththe mouth. Some energy is captured by the tidal analysis at

  4. Ocean Tidal Dissipation and its Role in Solar System Satellite Evolution

    E-Print Network [OSTI]

    Chen, Erinna

    2013-01-01

    Significant dissipation of tidal energy in the deep ocean2001. Estimates of M 2 tidal energy dissipation from TOPEX/e.g. the ocean kinetic energy and tidal dissipation, using a

  5. Snacktime for Hungry Black Holes: Theoretical Studies of the Tidal Disruption of Stars

    E-Print Network [OSTI]

    Strubbe, Linda Elisabeth

    2011-01-01

    tidal disruption rate as a function of pericenter distance at various energies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Tidal disruption rate as a function of pericenter distance at various energies2.5: Spectral energy distributions for tidal flares around a

  6. Binary asteroid systems: Tidal end states and estimates of material properties

    E-Print Network [OSTI]

    Taylor, PA; Margot, JL

    2011-01-01

    tidal evolution and then discuss stability limits and energyon tidal evolution. Angular momentum and energy content Theenergy can be dissipated as heat as a result of internal friction due to tidal ?

  7. Grid-Connected Renewable Energy Systems | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    and power quality, contracts (which may require liability insurance), and metering and rates. While renewable energy systems are capable of powering houses and small businesses...

  8. Prospects for grid-connected solar PV in Kenya

    E-Print Network [OSTI]

    Rose, Amy Michelle

    2013-01-01

    Kenya's electric power system is heavily reliant on hydropower, leaving it vulnerable during recurring droughts. Supply shortfalls are currently met through the use of expensive leased diesel generation. Therefore, plans ...

  9. Controlling of grid connected photovoltaic lighting system with fuzzy logic

    SciTech Connect (OSTI)

    Saglam, Safak; Ekren, Nazmi; Erdal, Hasan

    2010-02-15

    In this study, DC electrical energy produced by photovoltaic panels is converted to AC electrical energy and an indoor area is illuminated using this energy. System is controlled by fuzzy logic algorithm controller designed with 16 rules. Energy is supplied from accumulator which is charged by photovoltaic panels if its energy would be sufficient otherwise it is supplied from grid. During the 1-week usage period at the semester time, 1.968 kWh energy is used from grid but designed system used 0.542 kWh energy from photovoltaic panels at the experiments. Energy saving is determined by calculations and measurements for one education year period (9 months) 70.848 kWh. (author)

  10. Grid-Connected Renewable Energy Generation Toolkit-Hydroelectric | Open

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View New PagesSustainableGlynn County,Solar Jump to:Resources JumpStrategyEnergy Information

  11. GROWDERS Demonstration of Grid Connected Electricity Systems (Smart Grid

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View New PagesSustainable Urban TransportFortistarFuelCellsEtcSilicon

  12. Public Meeting: Physical Characterization of Grid-Connected Commercial And

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCED MANUFACTURINGEnergy BillsNo. 195 - Oct. 7, 2011 | DepartmentFunds for2002 |Buildings

  13. Public Meeting: Physical Characterization of Smart and Grid-Connected

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCED MANUFACTURINGEnergy BillsNo. 195 - Oct. 7, 2011 | DepartmentFunds for2002 |BuildingsCommercial

  14. Grid-Connected Renewable Energy Systems Case Studies | Open Energy

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LISTStar2-0057-EA Jump to:ofEniaElectricHydroLegal Documents JumpInformation

  15. Performance Parameters for Grid-Connected PV Systems

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass mapSpeeding access| DepartmentPeer ReviewRadiationAward at SmallNational Renewable

  16. Nevada Deploys Grid-Connected Electricity from Enhanced Geothermal Systems

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergyTher i nAand DOEDepartment ofProgramImports byGeothermalDepartment ofNevada -- SEP,|

  17. Nevada Deploys Grid-Connected Electricity from Enhanced Geothermal Systems

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterested Parties -Department ofDepartmentNaturalEnergy| Department ofSummary of|

  18. Grid-Connected Renewable Energy Systems | Department of Energy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation Current HABFESOpportunitiesNERSC

  19. Transatlantic Workshop on Electric Vehicles and Grid Connectivity |

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirley Ann JacksonDepartment ofOffice|inWestMayBuildingTheEasements30, 2008:|WithEnergy

  20. Grid-Connected Renewable Energy Systems | Department of Energy

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirley Ann JacksonDepartment ofOffice ofofWindUpcomingcanGrid Integration The Wind Program works

  1. Grid-Connected Renewable Energy Systems | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE: Alternative Fuelsof Energy ServicesContracting Oversight Committee on Homeland

  2. United States Launches First Grid-Connected Offshore Wind Turbine |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE: Alternative FuelsofProgram: Report1538-1950 Timeline ofTurkeyProgramDepartment of Energy

  3. Lyman Alpha Absorption and Tidal Debris

    E-Print Network [OSTI]

    Simon L. Morris

    1994-09-29

    The origin and evolution of structure in the Universe is one of the major questions occupying astronomers today. An understanding of the Lyalpha absorbers seen in QSO spectra is an important part of this program since such absorbers can be traced back to very high redshifts. Their mere existence places constraints on the physical state of the intergalactic medium. The discovery of Lyalpha absorbers at low redshift allows us to estimate for the first time what fraction of low redshift Lyalpha absorbers are (i) randomly distributed, (ii) distributed like galaxies but not physically associated with luminous objects, (iii) actually part of the halos of luminous galaxies, or (iv) tidal tails within galaxy groups. Results from the sightline to the QSO 3C273 suggest that the majority of the absorbers are not associated with galaxies, but that there is a significant subset that are. The absorbers associated with galaxies may be produced in enormous gaseous disks surrounding normal spiral galaxies, or may be tidal material bound up in small groups of galaxies

  4. ORIGINAL PAPER Predicting Avian Abundance Within and Across Tidal

    E-Print Network [OSTI]

    Kelly, Maggi

    ORIGINAL PAPER Predicting Avian Abundance Within and Across Tidal Marshes Using Fine Scientists 2010 Abstract Tidal marsh monitoring and restoration can benefit from the union of fine developed statistical models with relatively high explanatory power. In each case, models were improved

  5. Virginia Wetlands Report Tools of the Tidal Shoreline

    E-Print Network [OSTI]

    Virginia Wetlands Report Tools of the Tidal Shoreline Management Trade Friday, October 13, 2006) technology with digital aerial photographs and the power of the Internet. They are accessible from desktop Comprehensive Coastal Inventory has produced several GIS tools for the tidal shoreline management trade

  6. Enhancing tidal harmonic analysis: Robust (hybrid L1 ) solutions

    E-Print Network [OSTI]

    Hickey, Barbara

    Enhancing tidal harmonic analysis: Robust (hybrid L1 =L2 ) solutions Keith E. Leffler Ã, David A 24 February 2008 Accepted 28 April 2008 Keywords: Tides Tidal analysis Harmonic analysis Robust is calculated from the power spectrum of the residual, a calculation that filters broad spectrum noise

  7. Tilted Baroclinic Tidal Vortices MIGUEL CANALS AND GENO PAWLAK

    E-Print Network [OSTI]

    MacCready, Parker

    Tilted Baroclinic Tidal Vortices MIGUEL CANALS AND GENO PAWLAK Department of Ocean and Resources coherence. It is suggested that this may lead to a conversion of potential energy into kinetic energy. 1 mixing of coastal waters (Mul- ler and Garrett 2003). Of particular importance is the tidally driven case

  8. Tidal Conversion at a Submarine Ridge FRANOIS PTRLIS

    E-Print Network [OSTI]

    Young, William R.

    ). Satellite altimetry has shown deep-sea tidal energy losses concentrated at submarine ridges and island arcsTidal Conversion at a Submarine Ridge FRANÇOIS PÉTRÉLIS Laboratoire de Physique Statistique, Ecole received 30 July 2003, in final form 20 January 2004) ABSTRACT The radiative flux of internal wave energy

  9. CONTROL ID: 1187959 TITLE: Climate destabilization on tidally locked exoplanets

    E-Print Network [OSTI]

    CONTROL ID: 1187959 TITLE: Climate destabilization on tidally locked exoplanets PRESENTATION TYPE-zone rocky planets, should be tidally locked. We will discuss two different feedbacks that can destabilize cause a runaway climate shift. We use an idealized energy balance model to illustrate the scope

  10. Tidal deformation of a slowly rotating material body. External metric

    E-Print Network [OSTI]

    Philippe Landry; Eric Poisson

    2015-07-31

    We construct the external metric of a slowly rotating, tidally deformed material body in general relativity. The tidal forces acting on the body are assumed to be weak and to vary slowly with time, and the metric is obtained as a perturbation of a background metric that describes the external geometry of an isolated, slowly rotating body. The tidal environment is generic and characterized by two symmetric-tracefree tidal moments E_{ab} and B_{ab}, and the body is characterized by its mass M, its radius R, and a dimensionless angular-momentum vector \\chi^a new quantities, which we designate as rotational-tidal Love numbers. All these Love numbers are gauge invariant in the usual sense of perturbation theory, and all vanish when the body is a black hole.

  11. Confusion around the tidal force and the centrifugal force

    E-Print Network [OSTI]

    Matsuda, Takuya; Boffin, Henri M J

    2015-01-01

    We discuss the tidal force, whose notion is sometimes misunderstood in the public domain literature. We discuss the tidal force exerted by a secondary point mass on an extended primary body such as the Earth. The tidal force arises because the gravitational force exerted on the extended body by the secondary mass is not uniform across the primary. In the derivation of the tidal force, the non-uniformity of the gravity is essential, and inertial forces such as the centrifugal force are not needed. Nevertheless, it is often asserted that the tidal force can be explained by the centrifugal force. If we literally take into account the centrifugal force, it would mislead us. We therefore also discuss the proper treatment of the centrifugal force.

  12. Disc formation from stellar tidal disruptions

    E-Print Network [OSTI]

    Bonnerot, Clément; Lodato, Giuseppe; Price, Daniel J

    2015-01-01

    The potential of tidal disruption of stars to probe otherwise quiescent supermassive black holes cannot be exploited, if their dynamics is not fully understood. So far, the observational appearance of these events has been commonly derived from analytical extrapolations of the debris dynamical properties just after the stellar disruption. In this paper, we perform hydrodynamical simulations of stars in highly eccentric orbits, that follow the stellar debris after disruption and investigate their ultimate fate. We demonstrate that gas debris circularize on an orbital timescale because relativistic apsidal precession causes the stream to self-cross. The higher the eccentricity and/or the deeper the encounter, the faster is the circularization. If the internal energy deposited by shocks during stream self-interaction is readily radiated, the gas forms a narrow ring at the circularization radius. It will then proceed to accrete viscously at a super-Eddington rate, puffing up under radiation pressure. If instead c...

  13. Uncovering CDM halo substructure with tidal streams

    E-Print Network [OSTI]

    R. A. Ibata; G. F. Lewis; M. J. Irwin

    2001-10-31

    Models for the formation and growth of structure in a cold dark matter dominated universe predict that galaxy halos should contain significant substructure. Studies of the Milky Way, however, have yet to identify the expected few hundred sub-halos with masses greater than about 10^6 Msun. Here we propose a test for the presence of sub-halos in the halos of galaxies. We show that the structure of the tidal tails of ancient globular clusters is very sensitive to heating by repeated close encounters with the massive dark sub-halos. We discuss the detection of such an effect in the context of the next generation of astrometric missions, and conclude that it should be easily detectable with the GAIA dataset. The finding of a single extended cold stellar stream from a globular cluster would support alternative theories, such as self-interacting dark matter, that give rise to smoother halos.

  14. Tidal Downsizing model. I. Numerical methods: saving giant planets from tidal disruptions

    E-Print Network [OSTI]

    Nayakshin, Sergei

    2014-01-01

    Tidal Downsizing (TD) is a recently developed planet formation theory that supplements the classical Gravitational disc Instability (GI) model with planet migration inward and tidal disruptions of GI fragments in the inner regions of the disc. Numerical methods for a detailed population synthesis of TD planets are presented here. As an example application, the conditions under which GI fragments collapse faster than they migrate into the inner $a\\sim$ few AU disc are considered. It is found that most gas fragments are tidally or thermally disrupted unless (a) their opacity is $\\sim 3$ orders of magnitude less than the interstellar dust opacity at metallicities typical of the observed giant planets, or (b) the opacity is high but the fragments accrete large dust grains (pebbles) from the disc. Case (a) models produce very low mass solid cores ($M_{\\rm core} < 0.1$ Earth masses) and follow a negative correlation of giant planet frequency with host star metallicity. In contrast, case (b) models produce massiv...

  15. Palomar 5 and its Tidal Tails: A Search for New Members in the Tidal Stream

    E-Print Network [OSTI]

    Kuzma, Pete; Keller, Stefan; Maunder, Elizabeth

    2014-01-01

    In this paper we present the results of a search for members of the globular cluster Palomar 5 and its associated tidal tails. The analysis has been performed using intermediate and low resolution spectroscopy with the AAOmega spectrograph on the Anglo-Australian Telescope. Based on kinematics, line strength and photometric information, we identify 39 new red giant branch stars along $\\sim$20$^{\\circ}$ of the tails, a larger angular extent than has been previously studied. We also recover eight previously known tidal tail members. Within the cluster, we find seven new red giant and one blue horizontal branch members and confirm a further twelve known red giant members. In total, we provide velocity data for 67 stars in the cluster and the tidal tails. Using a maximum likelihood technique, we derive a radial velocity for Pal 5 of $-57.4 \\pm 0.3$ km s$^{-1}$ and a velocity dispersion of $1.2\\pm0.3$ km s$^{-1}$. We confirm and extend the linear velocity gradient along the tails of $1.0 \\pm 0.1$ km s$^{-1}$ deg$^...

  16. Investigating the Influence of the Added Mass Effect to Marine Hydrokinetic Horizontal-Axis Turbines Using a General Dynamic Wake Wind Turbine Code

    SciTech Connect (OSTI)

    Maniaci, D. C.; Li, Y.

    2011-10-01

    This paper describes a recent study to investigate the applicability of a horizontal-axis wind turbine (HAWT) structural dynamics and unsteady aerodynamics analysis program (FAST and AeroDyn respectively) to modeling the forces on marine hydrokinetic (MHK) turbines. This paper summarizes the added mass model that has been added to AeroDyn. The added mass model only includes flow acceleration perpendicular to the rotor disc, and ignores added mass forces caused by blade deflection. A model of the National Renewable Energy Laboratory's (NREL) Unsteady Aerodynamics Experiment (UAE) Phase VI wind turbine was analyzed using FAST and AeroDyn with sea water conditions and the new added mass model. The results of this analysis exhibited a 3.6% change in thrust for a rapid pitch case and a slight change in amplitude and phase of thrust for a case with 30{sup o} of yaw.

  17. Investigating the Influence of the Added Mass Effect to Marine Hydrokinetic Horizontal-Axis Turbines Using a General Dynamic Wake Wind Turbine Code: Preprint

    SciTech Connect (OSTI)

    Maniaci, D. C.; Li, Y.

    2012-04-01

    This paper describes a recent study to investigate the applicability of a horizontal-axis wind turbine (HAWT) structural dynamics and unsteady aerodynamics analysis program (FAST and AeroDyn respectively) to modeling the forces on marine hydrokinetic (MHK) turbines. It summarizes the added mass model that has been added to AeroDyn. The added mass model only includes flow acceleration perpendicular to the rotor disc, and ignores added mass forces caused by blade deflection. A model of the National Renewable Energy Laboratory's (NREL) Unsteady Aerodynamics Experiment (UAE) Phase VI wind turbine was analyzed using FAST and AeroDyn with sea water conditions and the new added mass model. The results of this analysis exhibited a 3.6% change in thrust for a rapid pitch case and a slight change in amplitude and phase of thrust for a case with 30 degrees of yaw.

  18. Measurement of Tidal Form Drag Using Seafloor Pressure Sensors SALLY J. WARNER AND PARKER MACCREADY

    E-Print Network [OSTI]

    MacCready, Parker

    tides. The tidally averaged power removed from the tidal currents by form drag was 0.2 W m22 , whichMeasurement of Tidal Form Drag Using Seafloor Pressure Sensors SALLY J. WARNER AND PARKER MACCREADY the tidal form drag on a sloping ridge in 200 m of water that forms a 1-km headland at the surface in Puget

  19. Under consideration for publication in J. Fluid Mech. 1 Reflecting tidal wave beams and local

    E-Print Network [OSTI]

    were generated locally by a propagating beam of internal tidal energy which had originatedUnder consideration for publication in J. Fluid Mech. 1 Reflecting tidal wave beams and local generation mecha- nism: tidal flow over steep topography forces a propagating beam of internal tidal wave

  20. Hydrodynamic analysis of a vertical axis tidal current turbine 

    E-Print Network [OSTI]

    Gretton, Gareth I.

    2009-01-01

    Tidal currents can be used as a predictable source of sustainable energy, and have the potential to make a useful contribution to the energy needs of the UK and other countries with such a resource. One of the technologies ...

  1. Numerical and Experimental Investigation of Tidal Current Energy Extraction 

    E-Print Network [OSTI]

    Sun, Xiaojing

    2008-01-01

    Numerical and experimental investigations of tidal current energy extraction have been conducted in this study. A laboratory-scale water flume was simulated using commercial computational fluid dynamics (CFD) code FLUENT. ...

  2. Geomorphic structure of tidal hydrodynamics in salt marsh creeks

    E-Print Network [OSTI]

    Fagherazzi, Sergio

    .1029/2007WR006289. 1. Introduction [2] Salt marshes are important transitional areas between terrestrial providing preferen- tial pathways for marsh flooding and drainage during the tidal cycle. Because

  3. Sandia Energy - Tidal Energy Resource Assessment in the East River Tidal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation of Fe(II)GeothermalFuel Magnetization andStochasticunique wind(CREW)Tidal

  4. A Bright Year for Tidal Disruptions?

    E-Print Network [OSTI]

    Metzger, Brian D

    2015-01-01

    When a star is tidally disrupted by a supermassive black hole (BH), roughly half of its mass falls back to the BH at super-Eddington rates. Being tenuously gravitationally bound and unable to cool radiatively, only a small fraction f_in few 1e4 K, converting the emission to optical/near-UV wavelengths where photons more readily escape due to the lower opacity. This can explain the unexpectedly low and temporally constant effective temperatures of optically-discovered TDE flares. For BHs with relatively high masses M_BH > 1e7 M_sun the ejecta can become ionized at an earlier stage, or for a wider range of viewing angles, producing a TDE flare which is instead dominated by thermal X-ray emission. We predict total radiated energies consistent with those of observed TDE flares, and ejecta velocities that agree with the measured emission line widths. The peak optical luminosity for M_BH wind, possibly contributing to the unexpected dearth of o...

  5. DOE Awards Up to $14.6 Million to Support Development of Advanced...

    Office of Environmental Management (EM)

    will produce information needed to determine the potential for injury and mortality of fish that encounter hydrokinetic turbines of various designs installed in tidal and river...

  6. Sandia Energy - EC Publications

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    project to benchmark a set of marine and hydrokinetic technologies including current (tidal, open-ocean, and river) turbines and wave energy converters. The objectives of the...

  7. Energy Department Announces Funding for Demonstration and Testing...

    Broader source: Energy.gov (indexed) [DOE]

    0 million to strengthen the U.S. marine and hydrokinetic (MHK) energy industry, including wave and tidal energy sources. Through the two funding opportunities announced today the...

  8. EQUATORIAL SUPERROTATION ON TIDALLY LOCKED EXOPLANETS

    SciTech Connect (OSTI)

    Showman, Adam P. [Department of Planetary Sciences and Lunar and Planetary Laboratory, University of Arizona, 1629 University Blvd., Tucson, AZ 85721 (United States); Polvani, Lorenzo M., E-mail: showman@lpl.arizona.edu [Department of Applied Physics and Applied Mathematics, Columbia University, New York, NY (United States)

    2011-09-01

    The increasing richness of exoplanet observations has motivated a variety of three-dimensional (3D) atmospheric circulation models of these planets. Under strongly irradiated conditions, models of tidally locked, short-period planets (both hot Jupiters and terrestrial planets) tend to exhibit a circulation dominated by a fast eastward, or 'superrotating', jet stream at the equator. When the radiative and advection timescales are comparable, this phenomenon can cause the hottest regions to be displaced eastward from the substellar point by tens of degrees longitude. Such an offset has been subsequently observed on HD 189733b, supporting the possibility of equatorial jets on short-period exoplanets. Despite its relevance, however, the dynamical mechanisms responsible for generating the equatorial superrotation in such models have not been identified. Here, we show that the equatorial jet results from the interaction of the mean flow with standing Rossby waves induced by the day-night thermal forcing. The strong longitudinal variations in radiative heating-namely intense dayside heating and nightside cooling-trigger the formation of standing, planetary-scale equatorial Rossby and Kelvin waves. The Rossby waves develop phase tilts that pump eastward momentum from high latitudes to the equator, thereby inducing equatorial superrotation. We present an analytic theory demonstrating this mechanism and explore its properties in a hierarchy of one-layer (shallow-water) calculations and fully 3D models. The wave-mean-flow interaction produces an equatorial jet whose latitudinal width is comparable to that of the Rossby waves, namely the equatorial Rossby deformation radius modified by radiative and frictional effects. For conditions typical of synchronously rotating hot Jupiters, this length is comparable to a planetary radius, explaining the broad scale of the equatorial jet obtained in most hot-Jupiter models. Our theory illuminates the dependence of the equatorial jet speed on forcing amplitude, strength of friction, and other parameters, as well as the conditions under which jets can form at all.

  9. Marine & Hydrokinetic Technologies

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergyTher i nAand DOE Safetyof Energy ThisSites |and theDepartmentPROGRAM C L E A N C

  10. Siting Methodologies for Hydrokinetics

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LIST OF APPLICABLE DIRECTIVES Pursuant toPower WindDepartment of Energy SiteFee09

  11. General relativistic tidal work for Papapetrou, Weinberg and Goldberg pseudotensors

    E-Print Network [OSTI]

    Lau Loi So

    2015-05-18

    In 1998 Thorne claimed that all pseudotensors give the same tidal work as the Newtonian theory. In 1999, Purdue used the Landau-Lifshitz pseudotensor to calculate the tidal heating and the result matched with the Newtonian gravity. Soon after in 2001, Favata employed the same method to examine the Einstein, Bergmann-Thomson and M{\\o}ller pseudotensors, all of them give the same result as Purdue did. Inspired by the work of Purdue and Favata, for the completeness, here we manipulate the tidal work for Papapetrou, Weinberg and Goldberg pseudotensors. We obtained the same tidal work as Purdue achieved. In addition, we emphasize that a suitable gravitational energy-momentum pseudotensor requires fulfill the inside matter condition and all of the classical pseudotensors pass this test except M$\\o$ller. Moreover, we constructed a general pseudotesnor which is modified by 13 linear artificial higher order terms combination with Einstein pseudotensor. We find that the result agrees with Thorne's prediction, i.e., relativistic tidal work is pseudotensor independent.

  12. NATIONAL GEODATABASE OF TIDAL STREAM POWER RESOURCE IN USA

    SciTech Connect (OSTI)

    Smith, Brennan T; Neary, Vincent S; Stewart, Kevin M

    2012-01-01

    A geodatabase of tidal constituents is developed to present the regional assessment of tidal stream power resource in the USA. Tidal currents are numerically modeled with the Regional Ocean Modeling System (ROMS) and calibrated with the available measurements of tidal current speeds and water level surfaces. The performance of the numerical model in predicting the tidal currents and water levels is assessed by an independent validation. The geodatabase is published on a public domain via a spatial database engine with interactive tools to select, query and download the data. Regions with the maximum average kinetic power density exceeding 500 W/m2 (corresponding to a current speed of ~1 m/s), total surface area larger than 0.5 km2 and depth greater than 5 m are defined as hotspots and documented. The regional assessment indicates that the state of Alaska (AK) has the largest number of locations with considerably high kinetic power density, followed by, Maine (ME), Washington (WA), Oregon (OR), California (CA), New Hampshire (NH), Massachusetts (MA), New York (NY), New Jersey (NJ), North and South Carolina (NC, SC), Georgia (GA), and Florida (FL).

  13. Variability in tidal disruption events: gravitationally unstable streams

    E-Print Network [OSTI]

    Coughlin, Eric R

    2015-01-01

    We present simulations of the tidal disruption of a solar mass star by a $10^6M_{\\odot}$ black hole. These, for the first time, cover the full time evolution of the tidal disruption event, starting well before the initial encounter and continuing until more than 90% of the bound material has returned to the vicinity of the hole. Our results are compared to the analytical prediction for the rate at which tidally-stripped gas falls back. We find that, for our chosen parameters, the overall scaling of the fallback rate, $\\dot{M}_{\\rm{fb}}$, closely follows the canonical $t^{-5/3}$ power-law. However, our simulations also show that the self-gravity of the tidal stream, which dominates the tidal gravity of the hole at large distances, causes some of the debris to recollapse into bound fragments before returning to the hole. This causes $\\dot{M}_{\\rm{fb}}$ to vary significantly around the $t^{-5/3}$ average. We discuss the implications of our findings in the context of the event Swift J1644+57.

  14. TIDAL DISRUPTION FLARES: THE ACCRETION DISK PHASE

    SciTech Connect (OSTI)

    Montesinos Armijo, Matias; De Freitas Pacheco, Jose A. [Observatoire de la Cote d'Azur, Laboratoire Cassiopee, Universite de Nice Sophia-Antipolis Bd de l'Observatoire, BP 4229, 06304 Nice Cedex 4 (France)

    2011-08-01

    The evolution of an accretion disk, formed as a consequence of the disruption of a star by a black hole, is followed by solving numerically hydrodynamic equations. The present investigation aims to study the dependence of resulting light curves on dynamical and physical properties of such a transient disk during its existence. One of the main results derived from our simulations is that blackbody fits of X-ray data tend to overestimate the true mean disk temperature. In fact, the temperature derived from blackbody fits should be identified with the color X-ray temperature rather than the average value derived from the true temperature distribution along the disk. The time interval between the beginning of the circularization of the bound debris and the beginning of the accretion process by the black hole is determined by the viscous (or accretion) timescale, which also fixes the rising part of the resulting light curve. The luminosity peak coincides with the beginning of matter accretion by the black hole and the late evolution of the light curve depends on the evolution of the debris fallback rate. Peak bolometric luminosities are in the range 10{sup 45}-10{sup 46} erg s{sup -1}, whereas peak luminosities in soft X-rays (0.2-2.0 keV) are typically one order of magnitude lower. The typical timescale derived from our preferred models for the flare luminosity to decay by two orders of magnitude is about 3-4 yr. Predicted soft X-ray light curves reproduce quite well data on galaxies in which a variable X-ray emission possibly related to a tidal event was detected. In the cases of NGC 3599 and IC 3599, data are reproduced well by models defined by a black hole with mass {approx}10{sup 7} M{sub sun} and a disrupted star of about 1 solar mass. The X-ray variation observed in XMMSL1 is consistent with a model defined by a black hole with mass {approx}3 x 10{sup 6} M{sub sun} and a disrupted star of 1 solar mass, while that observed in the galaxy situated in the cluster A1689 is consistent with a model including a black hole of {approx}10{sup 7} M{sub sun} and a disrupted star of {approx}0.5 M{sub sun}.

  15. A spatial characterization of the Sagittarius dwarf galaxy tidal tails

    SciTech Connect (OSTI)

    Newby, Matthew; Cole, Nathan; Newberg, Heidi Jo; Willett, Benjamin [Department of Physics, Applied Physics and Astronomy, Rensselaer Polytechnic Institute, Troy, NY 12180 (United States); Desell, Travis [Department of Computer Science, U. of North Dakota, Grand Forks, ND 52802 (United States); Magdon-Ismail, Malik; Szymanski, Boleslaw; Varela, Carlos [Department of Computer Science, Rensselaer Polytechnic Institute, Troy, NY 12180 (United States); Yanny, Brian, E-mail: newbym2@rpi.edu, E-mail: heidi@rpi.edu [Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510 (United States)

    2013-06-01

    We measure the spatial density of F turnoff stars in the Sagittarius dwarf tidal stream, from Sloan Digital Sky Survey data, using statistical photometric parallax. We find a set of continuous, consistent parameters that describe the leading Sgr stream's position, direction, and width for 15 stripes in the north Galactic cap, and three stripes in the south Galactic cap. We produce a catalog of stars that has the density characteristics of the dominant leading Sgr tidal stream that can be compared with simulations. We find that the width of the leading (north) tidal tail is consistent with recent triaxial and axisymmetric halo model simulations. The density along the stream is roughly consistent with common disruption models in the north, but possibly not in the south. We explore the possibility that one or more of the dominant Sgr streams has been misidentified, and that one or more of the ''bifurcated'' pieces is the real Sgr tidal tail, but we do not reach definite conclusions. If two dwarf progenitors are assumed, fits to the planes of the dominant and ''bifurcated'' tidal tails favor an association of the Sgr dwarf spheroidal galaxy with the dominant southern stream and the ''bifurcated'' stream in the north. In the north Galactic cap, the best fit Hernquist density profile for the smooth component of the stellar halo is oblate, with a flattening parameter q = 0.53, and a scale length of r {sub 0} = 6.73. The southern data for both the tidal debris and the smooth component of the stellar halo do not match the model fits to the north, although the stellar halo is still overwhelmingly oblate. Finally, we verify that we can reproduce the parameter fits on the asynchronous MilkyWay@home volunteer computing platform.

  16. Laboratory Analysis of Vortex Dynamics For Shallow Tidal Inlets 

    E-Print Network [OSTI]

    Whilden, Kerri Ann

    2010-10-12

    OF VORTEX DYNAMICS FOR SHALLOW TIDAL INLETS A Thesis by KERRI ANN WHILDEN Submitted to the O ce of Graduate Studies of Texas A&M University in partial ful llment of the requirements for the degree of MASTER OF SCIENCE August 2009 Major Subject: Ocean... Engineering LABORATORY ANALYSIS OF VORTEX DYNAMICS FOR SHALLOW TIDAL INLETS A Thesis by KERRI ANN WHILDEN Submitted to the O ce of Graduate Studies of Texas A&M University in partial ful llment of the requirements for the degree of MASTER OF SCIENCE Approved...

  17. MHK Projects/Highlands Tidal Energy Project | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource HistoryScenarios Towards 2050 JumpCoos Bay OPTHalf Moon Cove TidalTidal Energy

  18. MHK Projects/Housatonic Tidal Energy Plant | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource HistoryScenarios Towards 2050 JumpCoos Bay OPTHalf Moon Cove TidalTidalHope

  19. On the Natural Frequency of Tidal Current Power Systems - A Discussion...

    Office of Scientific and Technical Information (OSTI)

    On the Natural Frequency of Tidal Current Power Systems - A Discussion of Sea Testing Citation Details In-Document Search Title: On the Natural Frequency of Tidal Current Power...

  20. Snacktime for Hungry Black Holes: Theoretical Studies of the Tidal Disruption of Stars

    E-Print Network [OSTI]

    Strubbe, Linda Elisabeth

    2011-01-01

    bound gas onto the BH powers the tidal disruption flare, andof an X-ray Power-law The candidate tidal disruption eventstidal disruption spectra will contain a high-energy power-

  1. Assessment of Energy Production Potential from Tidal Streams in the United States

    SciTech Connect (OSTI)

    Haas, Kevin A.; Fritz, Hermann M.; French, Steven P.; Smith, Brennan T.; Neary, Vincent

    2011-06-29

    The project documented in this report created a national database of tidal stream energy potential, as well as a GIS tool usable by industry in order to accelerate the market for tidal energy conversion technology.

  2. Modeling Tidal Freshwater Marsh Sustainability in the Sacramento–San Joaquin Delta Under a Broad Suite of Potential Future Scenarios

    E-Print Network [OSTI]

    Swanson, Kathleen M.; Drexler, Judith Z.; Fuller, Christopher C.; Schoellhamer, David H.

    2015-01-01

    Tidal Freshwater Marsh Sustainability in the Sacramento–Sanof pulsing events to sustainability. Estuaries Coasts 18:Evaluating tidal marsh sustainability in the face of sea-

  3. On the implications of incompressibility of the quantum mechanical wavefunction in the presence of tidal gravitational fields

    E-Print Network [OSTI]

    Minter, Stephen

    2010-01-01

    of being the tidal gravitational potential energy operator,the energy shift is negative, the tidal gravitational …eldtidal gravitational …eld is treated as a perturbation to the energy

  4. An Estimate of Tidal Energy Lost to Turbulence at the Hawaiian Ridge JODY M. KLYMAK

    E-Print Network [OSTI]

    Balasubramanian, Ravi

    An Estimate of Tidal Energy Lost to Turbulence at the Hawaiian Ridge JODY M. KLYMAK Scripps an estimate of 3 1.5 GW of tidal energy lost to turbulence dissipation within 60 km of the ridge and Toole 1997). Another closely related question is that of where tidal energy gets removed from the ocean

  5. The E ect of Barriers on The Tidal Range in Yong Ming Tang

    E-Print Network [OSTI]

    interest in constructing tidal barrages, either to control the tide or to extract power. CorrespondinglyThe E ect of Barriers on The Tidal Range in Estuaries Yong Ming Tang Abstract Numerical simulations of the shallow water equations are used to study the e ect of topographic barriers on the tidal range

  6. Underestimation of the UK Tidal David J.C. MacKay

    E-Print Network [OSTI]

    MacKay, David J.C.

    there and would deliver up to 40 GW (peak). In this note, I present back­of­envelope models of tidal power special cases) the power in tidal waves is not equal to the kinetic energy flux across a plane. These backUnder­estimation of the UK Tidal Resource David J.C. MacKay Cavendish Laboratory, University

  7. Under-estimation of the UK Tidal David J.C. MacKay

    E-Print Network [OSTI]

    MacKay, David J.C.

    there and would deliver up to 40 GW (peak). In this note, I present back-of-envelope models of tidal power special cases) the power in tidal waves is not equal to the kinetic energy flux across a plane. These backUnder-estimation of the UK Tidal Resource David J.C. MacKay Cavendish Laboratory, University

  8. Three-Dimensional Tidal Flow in an Elongated, Rotating Basin CLINTON D. WINANT

    E-Print Network [OSTI]

    Winant, Clinton D.

    Three-Dimensional Tidal Flow in an Elongated, Rotating Basin CLINTON D. WINANT Integrative-dimensional tidal circulation in an elongated basin of arbitrary depth is described with a linear, constant parcels tend to corkscrew into and out of the basin in a tidal period. The axial flow is only weakly

  9. 2306 JOURNAL OF THE ATMOSPHERIC SCIENCES Chaotic Trajectories of Tidally Perturbed Inertial Oscillations

    E-Print Network [OSTI]

    Boss, Emmanuel S.

    2306 JOURNAL OF THE ATMOSPHERIC SCIENCES Chaotic Trajectories of Tidally Perturbed Inertial ABSTRACT It is shown that tidal perturbations of a geopotential height in an inviscid, barot~opic atmos formulation of both ~he free, inertial, and the tidally forced problems permitted the application o~ the twi

  10. MARCH 2007 1 Tidal mixing hotspots governed by rapid parametric subharmonic instability

    E-Print Network [OSTI]

    MacKinnon, Jennifer

    at 21S demonstrate a rapid transfer of energy (over only a few days) to waves of half the tidal the generation site; overall 40 % of the tidal energy is dissipated locally. Further simulations indicate.9nearly 80 % of tidal energy is dissipated locally. Poleward of the critical latitude, M2/2

  11. Internal hydraulic jumps and overturning generated by tidal flow over a tall steep ridge

    E-Print Network [OSTI]

    Klymak, Jody M.

    that tidal energy is both converted into internal waves, which radiate away from the topography, and used of tidal mixing for global climate models, the physical processes governing the transfer of energy fromInternal hydraulic jumps and overturning generated by tidal flow over a tall steep ridge Sonya Legg

  12. Are mesoscale eddies in shelf seas formed by baroclinic instability of tidal fronts?

    E-Print Network [OSTI]

    Williams, Ric

    Are mesoscale eddies in shelf seas formed by baroclinic instability of tidal fronts? G. Badin,1 R; accepted 23 July 2009; published 27 October 2009. [1] The formation of eddies along tidal fronts signals are dampened by air-sea interaction and eroded by wind and tidal mixing. High-resolution CTD

  13. Dissipation at tidal and seismic frequencies in a melt-free Moon U. H. Faul,2

    E-Print Network [OSTI]

    Nimmo, Francis

    Dissipation at tidal and seismic frequencies in a melt-free Moon F. Nimmo,1 U. H. Faul,2 and E. J. Successful models can reproduce the dissipation factor (Q) measured at both tidal and seismic frequencies, and the tidal Love numbers h2 and k2, without requiring any mantle melting. However, the frequency

  14. Tidal mixing around the Maritime continent: implications for1 paleoclimate simulations2

    E-Print Network [OSTI]

    into state-of-the-art climate models. Calculation of the tidal energy flux depends on 7 1 Tidal mixing around the Maritime continent: implications for1 paleoclimate simulations2, New Haven, CT, 06511 4 Abstract 5 Tidal mixing provides an important source

  15. Critical bifurcation of shallow microtidal landforms in tidal flats and salt marshes

    E-Print Network [OSTI]

    Fagherazzi, Sergio

    Critical bifurcation of shallow microtidal landforms in tidal flats and salt marshes Sergio by the Editorial Board April 14, 2006 (received for review September 25, 2005) Shallow tidal basins are characterized by extensive tidal flats and salt marshes that lie within specific ranges of elevation, whereas

  16. Seasonal variations of semidiurnal tidal perturbations in mesopause region temperature and zonal and meridional winds above

    E-Print Network [OSTI]

    to conserve wave energy. When propagating into the MLT region, the horizontal wind tidal amplitude can reachSeasonal variations of semidiurnal tidal perturbations in mesopause region temperature and zonal, Colorado (40.6°N, 105.1°W). The observed monthly results are in good agreement with MF radar tidal

  17. Spatial variability within a single parautochthonous Paratethyan tidal flat deposit (Karpatian, Lower Miocene Kleinebersdorf, Lower Austria)

    E-Print Network [OSTI]

    Zuschin, Martin

    Spatial variability within a single parautochthonous Paratethyan tidal flat deposit (Karpatian and Diplodonta rotundata points to a low-energy coastal setting with at least partly nutrient-rich sediment the interpretation of a parautochthonous to slightly transported tidal flat deposit. Key words: tidal flat, diversity

  18. Europa: Tidal heating of upwelling thermal plumes and the origin of lenticulae and chaos melting

    E-Print Network [OSTI]

    Head III, James William

    ; Pappalardo and Head, 2001], and 3) a seafloor plume model in which tidal energy focused in the silicate ice in the shallow crust of Europa. We show that tidal energy can be preferentially focused in risingEuropa: Tidal heating of upwelling thermal plumes and the origin of lenticulae and chaos melting

  19. Tidal and Wind Mixing versus Thermal Stratification in the South Atlantic Bight.

    E-Print Network [OSTI]

    North Carolina at Chapel Hill, University of

    ) these fluctuations are controlled by the cycles of tidally forced mixing, heat flux, wind and river discharge. During overcome the tendency for tidal power to produce a well-mixed system". Additionally, they expressed some: heat flux, evaporation-precipitation, fresh water input, wind stress work, bottom tidal work

  20. Virtual Seafloor Reduces Internal Wave Generation by Tidal Flow Likun Zhang*

    E-Print Network [OSTI]

    the applicability of linear theory to global predictions of the conversion of tidal energy into internal wave energy of the energy budget of the oceans requires a determination of the efficiency of conversion of tidal energyVirtual Seafloor Reduces Internal Wave Generation by Tidal Flow Likun Zhang* and Harry L. Swinney

  1. Identifying Pollutant Sources in Tidally Mixed Systems: Case Study

    E-Print Network [OSTI]

    Winant, Clinton D.

    sitessas a primary source of fecal indicator bacteria in the water column and subtidal sediments and magnitude of pollutant sources potentially responsible for the impairment. While this information mayIdentifying Pollutant Sources in Tidally Mixed Systems: Case Study of Fecal Indicator Bacteria from

  2. Squeezars: Tidally powered stars orbiting a massive black hole

    E-Print Network [OSTI]

    Alexander, T; Alexander, Tal; Morris, Mark

    2003-01-01

    We propose that there exists a class of transient sources, "squeezars", which are stars caught in highly eccentric orbits around a massive (m<10^8 Mo) black hole (MBH), whose atypically high luminosity (up to a significant fraction of their Eddington luminosity) is powered by tidal interactions with the MBH. Their existence follows from the presence of a mass sink, the MBH, in the galactic center, which drives a flow of stars into nearly radial orbits to replace those it has destroyed. We consider two limits for the stellar response to tidal heating: surface heating with radiative cooling ("hot squeezars") and bulk heating with adiabatic expansion ("cold squeezars"), and calculate the evolution of the squeezar orbit, size, luminosity and effective temperature. The squeezar formation rate is only ~0.05 that of tidal disruption flares, but squeezar lifetimes are many orders of magnitude longer, and so future observations of squeezars in nearby galaxies can probe the tidal process that feeds MBHs and the effe...

  3. General relativistic tidal work for Papapetrou, Weinberg and Goldberg pseudotensors

    E-Print Network [OSTI]

    So, Lau Loi

    2015-01-01

    In 1998 Thorne claimed that all pseudotensors give the same tidal work as the Newtonian theory. In 1999, Purdue used the Landau-Lifshitz pseudotensor to calculate the tidal heating and the result matched with the Newtonian gravity. Soon after in 2001, Favata employed the same method to examine the Einstein, Bergmann-Thomson and M{\\o}ller pseudotensors, all of them give the same result as Purdue did. Inspired by the work of Purdue and Favata, for the completeness, here we manipulate the tidal work for Papapetrou, Weinberg and Goldberg pseudotensors. We obtained the same tidal work as Purdue achieved. In addition, we emphasize that a suitable gravitational energy-momentum pseudotensor requires fulfill the inside matter condition and all of the classical pseudotensors pass this test except M$\\o$ller. Moreover, we constructed a general pseudotesnor which is modified by 13 linear artificial higher order terms combination with Einstein pseudotensor. We find that the result agrees with Thorne's prediction, i.e., rel...

  4. Squeezars: Tidally powered stars orbiting a massive black hole

    E-Print Network [OSTI]

    Tal Alexander; Mark Morris

    2003-05-05

    We propose that there exists a class of transient sources, "squeezars", which are stars caught in highly eccentric orbits around a massive (mpowered by tidal interactions with the MBH. Their existence follows from the presence of a mass sink, the MBH, in the galactic center, which drives a flow of stars into nearly radial orbits to replace those it has destroyed. We consider two limits for the stellar response to tidal heating: surface heating with radiative cooling ("hot squeezars") and bulk heating with adiabatic expansion ("cold squeezars"), and calculate the evolution of the squeezar orbit, size, luminosity and effective temperature. The squeezar formation rate is only ~0.05 that of tidal disruption flares, but squeezar lifetimes are many orders of magnitude longer, and so future observations of squeezars in nearby galaxies can probe the tidal process that feeds MBHs and the effects of extreme tides on stars. The mean number of squeezars orbiting the Galactic MBH is estimated at 0.1-1.

  5. Pasture and Soil Management Following Tidal Saltwater Intrusion 

    E-Print Network [OSTI]

    Provin, Tony; Redmon, Larry; McFarland, Mark L.; Feagley, Sam E.

    2009-05-26

    When land is flooded by saltwater, as after a hurricane tidal surge, it can long-term effects on soil productivity and fertility. This publication explains how to reclaim flooded pasture land. Having soil tested for salinity is an important step....

  6. Examining the Impacts of Tidal Energy Capture from an Ecosystem

    E-Print Network [OSTI]

    Leslie, Heather

    ; however, the contribution of alternative fuel sources to overall energy is still small. In the United are under development in the Northeast, includ- ing Roosevelt Island in New York City's East RiverP A P E R Examining the Impacts of Tidal Energy Capture from an Ecosystem Services Perspective A U

  7. Tidal Conversion by Supercritical Topography NEIL J. BALMFORTH

    E-Print Network [OSTI]

    Balmforth, Neil

    Tidal Conversion by Supercritical Topography NEIL J. BALMFORTH University of British Columbia topography on the ocean floor. The ocean is treated as infinitely deep, and the topography consists. The calculations extend the previous results of Balmforth et al. for subcritical topography (wherein waves

  8. First-post-Newtonian quadrupole tidal interactions in binary systems

    E-Print Network [OSTI]

    Justin Vines; Éanna É. Flanagan

    2014-10-09

    We consider tidal coupling in a binary stellar system to first-post-Newtonian order. We derive the orbital equations of motion for bodies with spins and mass quadrupole moments and show that they conserve the total linear momentum of the binary. We note that spin-orbit coupling must be included in a 1PN treatment of tidal interactions in order to maintain consistency (except in the special case of adiabatically induced quadrupoles); inclusion of 1PN quadrupolar tidal effects while omitting spin effects would lead to a failure of momentum conservation for generic evolution of the quadrupoles. We use momentum conservation to specialize our analysis to the system's center-of-mass-energy frame; we find the binary's relative equation of motion in this frame and also present a generalized Lagrangian from which it can be derived. We then specialize to the case in which the quadrupole moment is adiabatically induced by the tidal field (in which case it is consistent to ignore spin effects). We show how the adiabatic dynamics for the quadrupole can be incorporated into our action principle and present the simplified orbital equations of motion and conserved energy for the adiabatic case. These results are relevant to gravitational wave signals from inspiralling binary neutron stars.

  9. Energy Localization Invariance of Tidal Work in General Relativity

    E-Print Network [OSTI]

    Marc Favata

    2000-08-24

    It is well known that, when an external general relativistic (electric-type) tidal field E(t) interacts with the evolving quadrupole moment I(t) of an isolated body, the tidal field does work on the body (``tidal work'') -- i.e., it transfers energy to the body -- at a rate given by the same formula as in Newtonian theory: dW/dt = -1/2 E dI/dt. Thorne has posed the following question: In view of the fact that the gravitational interaction energy between the tidal field and the body is ambiguous by an amount of order E(t)I(t), is the tidal work also ambiguous by this amount, and therefore is the formula dW/dt = -1/2 E dI/dt only valid unambiguously when integrated over timescales long compared to that for I(t) to change substantially? This paper completes a demonstration that the answer is no; dW/dt is not ambiguous in this way. More specifically, this paper shows that dW/dt is unambiguously given by -1/2 E dI/dt independently of one's choice of how to localize gravitational energy in general relativity. This is proved by explicitly computing dW/dt using various gravitational stress-energy pseudotensors (Einstein, Landau-Lifshitz, Moller) as well as Bergmann's conserved quantities which generalize many of the pseudotensors to include an arbitrary function of position. A discussion is also given of the problem of formulating conservation laws in general relativity and the role played by the various pseudotensors.

  10. Modeling In-stream Tidal Energy Extraction and Its Potential Environmental Impacts

    SciTech Connect (OSTI)

    Yang, Zhaoqing; Wang, Taiping; Copping, Andrea; Geerlofs, Simon H.

    2014-09-30

    In recent years, there has been growing interest in harnessing in-stream tidal energy in response to concerns of increasing energy demand and to mitigate climate change impacts. While many studies have been conducted to assess and map tidal energy resources, efforts for quantifying the associated potential environmental impacts have been limited. This paper presents the development of a tidal turbine module within a three-dimensional unstructured-grid coastal ocean model and its application for assessing the potential environmental impacts associated with tidal energy extraction. The model is used to investigate in-stream tidal energy extraction and associated impacts on estuarine hydrodynamic and biological processes in a tidally dominant estuary. A series of numerical experiments with varying numbers and configurations of turbines installed in an idealized estuary were carried out to assess the changes in the hydrodynamics and biological processes due to tidal energy extraction. Model results indicated that a large number of turbines are required to extract the maximum tidal energy and cause significant reduction of the volume flux. Preliminary model results also indicate that extraction of tidal energy increases vertical mixing and decreases flushing rate in a stratified estuary. The tidal turbine model was applied to simulate tidal energy extraction in Puget Sound, a large fjord-like estuary in the Pacific Northwest coast.

  11. Effects of Electromagnetic Fields on Fish and Invertebrates Task 2.1.3: Effects on Aquatic Organisms Fiscal Year 2012 Progress Report Environmental Effects of Marine and Hydrokinetic Energy

    SciTech Connect (OSTI)

    Woodruff, Dana L.; Cullinan, Valerie I.; Copping, Andrea E.; Marshall, Kathryn E.

    2013-05-20

    Energy generated by the world’s oceans and rivers offers the potential to make substantial contributions to the domestic and global renewable energy supply. However, the marine and hydrokinetic (MHK) energy industry faces challenges related to siting, permitting, construction, and operation of pilotand commercial-scale facilities. One of the challenges is to understand the potential effects to marine organisms from electromagnetic fields, which are produced as a by-product of transmitting power from offshore to onshore locations through underwater transmission cables. This report documents the progress of the third year of research (fiscal year 2012) to investigate environmental issues associated with marine and hydrokinetic energy (MHK) generation. This work was conducted by Pacific Northwest National Laboratory (PNNL) for the U.S. Department of Energy’s (DOE’s) Office of Energy Efficiency and Renewable Energy (EERE) Wind and Water Technologies Office. The report addresses the effects of electromagnetic fields (EMFs) on selected marine species where significant knowledge gaps exist. The species studied this fiscal year included one fish and two crustacean species: the Atlantic halibut (Hippoglossus hippoglossus), Dungeness crab (Metacarcinus magister), and American lobster (Homarus americanus).

  12. Tidal dissipation in a homogeneous spherical body. I. Methods

    SciTech Connect (OSTI)

    Efroimsky, Michael; Makarov, Valeri V. E-mail: vvm@usno.navy.mil

    2014-11-01

    A formula for the tidal dissipation rate in a spherical body is derived from first principles to correct some mathematical inaccuracies found in the literature. The development is combined with the Darwin-Kaula formalism for tides. Our intermediate results are compared with those by Zschau and Platzman. When restricted to the special case of an incompressible spherical planet spinning synchronously without libration, our final formula can be compared with the commonly used expression from Peale and Cassen. However, the two turn out to differ, as in our expression the contributions from all Fourier modes are positive-definite, which is not the case with the formula from Peale and Cassen. Examples of the application of our expression for the tidal damping rate are provided in the work by Makarov and Efroimsky (Paper II) published back to back with the current paper.

  13. EA-1949: Admiralty Inlet Pilot Tidal Project, Puget Sound, WA

    Broader source: Energy.gov [DOE]

    This EA analyzes the potential environmental effects of a proposal by the Public Utility District No. 1 of Snohomish County, Washington to construct and operate the Admiralty Inlet Tidal Project. The proposed 680-kilowatt project would be located on the east side of Admiralty Inlet in Puget Sound, Washington, about 1 kilometer west of Whidbey Island, entirely within Island County, Washington. The Federal Energy Regulatory Commission (FERC) is the lead agency. The DOE NEPA process for this project has been canceled.

  14. On the circulation and tidal flushing of Mobile Bay, Alabama 

    E-Print Network [OSTI]

    Austin, George Belden

    1953-01-01

    of Symbols, Tables ~ . . . I, INTRODUCTION Historical B. Classification of Estuaries C. Ob]ectives II. GENERAL DISCUSSION OF NOBILE BAY A. Geomorphological B. Geological C. Biological iii ~ ~ vi ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ o sic.... Collection of Data 27 2B V, ANALYSIS OF THE DATA A. Methods B. Distribution of Temperature, Salinity, and Fresh Water Page 30 30 C. Circulation D. Mass Transport . E. Tidal Flushing of Mobile Bay . VI ~ SUMMAHY AND CONCLUSIONS VII, BIBLIOGRAPHY...

  15. Severn Tidal Power Group STpg | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-Enhancing Capacity for Low Emission DevelopmentLakes, North Carolina:Severn Tidal

  16. Forced libration of tidally synchronized planets and moons

    E-Print Network [OSTI]

    Makarov, Valeri V; Dorland, Bryan

    2015-01-01

    Tidal dissipation of kinetic energy, when it is strong enough, tends to synchronize the rotation of planets and moons with the mean orbital motion, or drive it into long-term stable spin-orbit resonances. As the orbital motion undergoes periodic acceleration due to a finite orbital eccentricity, the spin rate oscillates around the equilibrium mean value too, giving rise to the forced, or eccentricity-driven, librations. Both the shape and amplitude of forced librations of synchronous viscoelastic planets and moons are defined by a combination of two different types of perturbative torque, the tidal torque and the triaxial torque. Consequently, forced librations can be tidally dominated (e.g., Io and possibly Titan) or deformation-dominated (e.g., the Moon) depending on a set of orbital, rheological, and other physical parameters. With small eccentricities, for the former kind, the largest term in the libration angle can be minus cosine of the mean anomaly, whereas for the latter kind, it is minus sine of the ...

  17. The Arches Cluster: Extended Structure and Tidal Radius

    E-Print Network [OSTI]

    Hosek, Matthew W; Anderson, Jay; Ghez, Andrea M; Morris, Mark R; Clarkson, William I

    2015-01-01

    At a projected distance of ~26 pc from Sgr A*, the Arches cluster provides insight to star formation in the extreme Galactic Center (GC) environment. Despite its importance, many key properties such as the cluster's internal structure and orbital history are not well known. We present an astrometric and photometric study of the outer region of the Arches cluster (R > 6.25") using HST WFC3IR. Using proper motions we calculate membership probabilities for stars down to F153M = 20 mag (~2.5 M_sun) over a 120" x 120" field of view, an area 144 times larger than previous astrometric studies of the cluster. We construct the radial profile of the Arches to a radius of 75" (~3 pc at 8 kpc), which can be well described by a single power law. From this profile we place a 3-sigma lower limit of 2.8 pc on the observed tidal radius, which is larger than the predicted tidal radius (1 - 2.5 pc). Evidence of mass segregation is observed throughout the cluster and no tidal tail structures are apparent along the orbital path. ...

  18. On the tidal radius of satellites on prograde and retrograde orbits

    E-Print Network [OSTI]

    Gajda, Grzegorz

    2015-01-01

    A tidal radius is a distance from a satellite orbiting in a host potential beyond which its material is stripped by the tidal force. We derive a revised expression for the tidal radius of a rotating satellite which properly takes into account the possibility of prograde and retrograde orbits of stars. Besides the eccentricity of the satellite orbit, the tidal radius depends also on the ratio of the satellite internal angular velocity to the orbital angular velocity. We compare our formula to the results of two $N$-body simulations of dwarf galaxies orbiting a Milky Way-like host on a prograde and retrograde orbit. The tidal radius for the retrograde case is larger than for the prograde. We introduce a kinematic radius separating stars still orbiting the dwarf galaxy from those already stripped and following the potential of the host galaxy. We find that the tidal radius matches very well the kinematic radius.

  19. Analysis of tidal current observations over the northeastern shelf of the Gulf of Mexico 

    E-Print Network [OSTI]

    Durham, Donald L

    1967-01-01

    LIST OF FIGURES Chapter TABLE OF CONTENTS Page vi vii IV INTRODUCTION A. Statement of Problem B. Literature Review 1. Tidal Current Theory 2. Tidal Current Observations INSTRUMENTATION AND DATA COLLECTION A. Selection and Modification... of Equipment B. September 1965 Survey DATA ANALYSIS AND RESULTS A. The Surface Tide 1. General 2. Gulf of Mexico B. Current Components C. Spectral Analysis D. Harmonic Analysis E. Tidal Ellipse F, Temperature CONCLUSIONS 1 1 2 2 11 15 15 21...

  20. Mechanisms generating modification of benthos following tidal flat invasion by a Spartina hybrid

    E-Print Network [OSTI]

    Neira, C; Grosholz, E D; Levin, L A; Blake, R

    2006-01-01

    1997. Kinetics of tidal resuspension of microbiota: testingare susceptible to resuspension following bio- turbation (in barnacle recruitment and resuspension of adult benthic

  1. MECHANISMS GENERATING MODIFICATION OF BENTHOS FOLLOWING TIDAL FLAT INVASION BY A SPARTINA HYBRID

    E-Print Network [OSTI]

    Neira, Carlos; Grosholz, Edwin D; Levin, Lisa A; Blake, Rachael

    2006-01-01

    1997. Kinetics of tidal resuspension of microbiota: testingare susceptible to resuspension following bio- turbation (in barnacle recruitment and resuspension of adult benthic

  2. Assessment of Strike of Adult Killer Whales by an OpenHydro Tidal Turbine Blade

    SciTech Connect (OSTI)

    Carlson, Thomas J.; Elster, Jennifer L.; Jones, Mark E.; Watson, Bruce E.; Copping, Andrea E.; Watkins, Michael L.; Jepsen, Richard A.; Metzinger, Kurt

    2012-02-01

    Report to DOE on an analysis to determine the effects of a potential impact to an endangered whale from tidal turbines proposed for deployment in Puget Sound.

  3. Modeling the Effects of Tidal Energy Extraction on Estuarine Hydrodynamics in a Stratified Estuary

    SciTech Connect (OSTI)

    Yang, Zhaoqing; Wang, Taiping

    2013-08-15

    A three-dimensional coastal ocean model with a tidal turbine module was used in this paper to study the effects of tidal energy extraction on temperature and salinity stratification and density driven two-layer estuarine circulation. Numerical experiments with various turbine array configurations were carried out to investigate the changes in tidally mean temperature, salinity and velocity profiles in an idealized stratified estuary that connects to coastal water through a narrow tidal channel. The model was driven by tides, river inflow and sea surface heat flux. To represent the realistic size of commercial tidal farms, model simulations were conducted based on a small percentage of the total number of turbines that would generate the maximum extractable energy in the system. Model results indicated that extraction of tidal energy will increase the vertical mixing and decrease the stratification in the estuary. Extraction of tidal energy has stronger impact on the tidally-averaged salinity, temperature and velocity in the surface layer than the bottom. Energy extraction also weakens the two-layer estuarine circulation, especially during neap tides when tidal mixing the weakest and energy extraction is the smallest. Model results also show that energy generation can be much more efficient with higher hub height with relatively small changes in stratification and two-layer estuarine circulation.

  4. Tapping into Wave and Tidal Ocean Power: 15% Water Power by 2030...

    Broader source: Energy.gov (indexed) [DOE]

    Office What are the key documents? Mapping and Assessment of the United States Ocean Wave Energy Resource pdf here Assessment of Energy Production Potential from Tidal Streams...

  5. Jets from Tidal Disruptions of Stars by Black Holes

    E-Print Network [OSTI]

    Julian H. Krolik; Tsvi Piran

    2012-02-07

    Tidal disruption of main sequence stars by black holes has generally been thought to lead to a signal dominated by UV emission. If, however, the black hole spins rapidly and the poloidal magnetic field intensity on the black hole horizon is comparable to the inner accretion disk pressure, a powerful jet may form whose luminosity can easily exceed the thermal UV luminosity. When the jet beam points at Earth, its non-thermal luminosity can dominate the emitted spectrum. The thermal and non-thermal components decay differently with time. In particular, the thermal emission should remain roughly constant for a significant time after the period of maximum accretion, beginning to diminish only after a delay, whereas after the peak accretion rate, the non-thermal jet emission decays, but then reaches a plateau. Both transitions are tied to a characteristic timescale $t_{\\rm Edd}$ at which the accretion rate falls below Eddington. Making use of this timescale in a new parameter-inference formalism for tidal disruption events with significant emission from a jet, we analyze the recent flare source Swift J2058. It is consistent with an event in which a main sequence solar-type staris disrupted by a black hole of mass $\\sim 4 \\times 10^7 M_{\\odot}$. The beginning of the flat phase in the non-thermal emission from this source can possibly be seen in the late-time lightcurve. Optical photometry over the first $\\simeq 40$ d of this flare is also consistent with this picture, but is only weakly constraining because the bolometric correction is very uncertain. We suggest that future searches for main sequence tidal disruptions use methods sensitive to jet radiation as well as to thermal UV radiation.

  6. MHK Projects/Rockaway Tidal Energy Plant | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas:Montezuma,Information MHKMHK5 < MHKKembla < MHK Projects JumpRockaway Tidal

  7. The Wash Tidal Barrier Corporation | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop Inc JumpHeterInformation Policy andInstitute JumpWash Tidal Barrier

  8. List of Tidal Energy Incentives | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource History ViewInformationWindsCompressedList of RefuelingRoomList ofSolarTidal

  9. MHK Projects/Avalon Tidal | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource HistoryScenarios Towards 2050 Jump to:Projects/Alaska 31 <Avalon Tidal < MHK

  10. MHK Projects/BW2 Tidal | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource HistoryScenarios Towards 2050 Jump to:Projects/Alaska 31 <Avalon Tidal <BW2

  11. MHK Projects/Cape May Tidal Energy | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource HistoryScenarios Towards 2050 Jump to:Projects/Alaska 31BondurantCETO3May Tidal

  12. MHK Projects/Killisnoo Tidal Energy | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource HistoryScenarios Towards 2050 JumpCoos Bay OPTHalf MoonKillisnoo Tidal Energy <

  13. MHK Projects/Kingsbridge Tidal Energy Project | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource HistoryScenarios Towards 2050 JumpCoos Bay OPTHalf MoonKillisnoo Tidal Energy

  14. MHK Projects/Margate Tidal | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource HistoryScenarios Towards 2050 JumpCoos Bay OPTHalf| Open EnergyMaineMargate Tidal

  15. MHK Projects/Maurice River Tidal | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource HistoryScenarios Towards 2050 JumpCoos Bay OPTHalf| OpenMaurice River Tidal <

  16. MHK Projects/Salem Tidal Energy | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource HistoryScenarios Towards 2050 JumpCoos BayOysterReliance LightSalem Tidal Energy

  17. MHK Technologies/Sabella subsea tidal turbine | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource HistoryScenarios Towards 2050Enermar <OMIS D E < MHKSPERBOY <subsea tidal

  18. Hydropower, Wave and Tidal Technologies - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation CurrentHenry Bellamy, Ph.D.FoodHydropower, Wave and Tidal » Technology

  19. Sandia Energy - Tidal & Current Modeling Development and Validation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation of Fe(II)GeothermalFuel Magnetization andStochasticunique wind(CREW)Tidal &

  20. RED CLUMP STARS IN THE SAGITTARIUS TIDAL STREAMS

    SciTech Connect (OSTI)

    Carrell, Kenneth; Chen Yuqin; Wilhelm, Ronald

    2012-07-15

    We have probed a section (l {approx} 150, b {approx} -60) of the trailing tidal arm of the Sagittarius dwarf spheroidal galaxy by identifying a sample of Red Clump (RC) stream stars. RC stars are not generally found in the halo field, but are found in significant numbers in both the Sagittarius galaxy and its tidal streams, making them excellent probes of stream characteristics. Our target sample was selected using photometric data from the Sloan Digital Sky Survey, Data Release 6, which was constrained in color to match the Sagittarius RC stars. Spectroscopic observations of the target stars were conducted at Kitt Peak National Observatory using the WIYN telescope. The resulting spectroscopic sample is magnitude limited and contains both main-sequence disk stars and evolved RC stars. We have developed a method to systematically separate these two stellar classes using kinematic information and a Bayesian approach for surface gravity determination. The resulting RC sample allows us to determine an absolute stellar density of {rho} = 2.7 {+-} 0.5 RC stars kpc{sup -3} at this location in the stream. Future measurements of stellar densities for a variety of populations and at various locations along the streams will lead to a much improved understanding of the original nature of the Sagittarius galaxy and the physical processes controlling its disruption and subsequent stream generation.

  1. Relativistic effects on tidal disruption kicks of solitary stars

    E-Print Network [OSTI]

    Gafton, Emanuel; Guillochon, James; Korobkin, Oleg; Rosswog, Stephan

    2015-01-01

    Solitary stars that wander too close to their galactic centres can become tidally disrupted, if the tidal forces due to the supermassive black hole (SMBH) residing there overcome the self-gravity of the star. If the star is only partially disrupted, so that a fraction survives as a self-bound object, this remaining core will experience a net gain in specific orbital energy, which translates into a velocity "kick" of up to $\\sim 10^3$ km/s. In this paper, we present the result of smoothed particle hydrodynamics (SPH) simulations of such partial disruptions, and analyse the velocity kick imparted on the surviving core. We compare $\\gamma$ = 5/3 and $\\gamma$ = 4/3 polytropes disrupted in both a Newtonian potential, and a generalized potential that reproduces most relativistic effects around a Schwarzschild black hole either exactly or to excellent precision. For the Newtonian case, we confirm the results of previous studies that the kick velocity of the surviving core is virtually independent of the ratio of the...

  2. The Magellanic Bridge: The Nearest Purely Tidal Stellar Population

    E-Print Network [OSTI]

    Jason Harris

    2006-12-04

    We report on observations of the stellar populations in twelve fields spanning the region between the Magellanic Clouds, made with the Mosaic-II camera on the 4-meter telescope at the Cerro-Tololo Inter-American Observatory. The two main goals of the observations are to characterize the young stellar population (which presumably formed in situ in the Bridge and therefore represents the nearest stellar population formed from tidal debris), and to search for an older stellar component (which would have been stripped from either Cloud as stars, by the same tidal forces which formed the gaseous Bridge). We determine the star-formation history of the young inter-Cloud population, which provides a constraint on the timing of the gravitational interaction which formed the Bridge. We do not detect an older stellar population belonging to the Bridge in any of our fields, implying that the material that was stripped from the Clouds to form the Magellanic Bridge was very nearly a pure gas.

  3. Tidal Dwarf Galaxies: Disc Formation at z=0

    E-Print Network [OSTI]

    Lelli, Federico; Brinks, Elias; McGaugh, Stacy S

    2015-01-01

    Collisional debris around interacting and post-interacting galaxies often display condensations of gas and young stars that can potentially form gravitationally bound objects: Tidal Dwarf Galaxies (TDGs). We summarise recent results on TDGs, which are originally published in Lelli et al. (2015, A&A). We study a sample of six TDGs around three different interacting systems, using high-resolution HI observations from the Very Large Array. We find that the HI emission associated to TDGs can be described by rotating disc models. These discs, however, would have undergone less than one orbit since the time of the TDG formation, raising the question of whether they are in dynamical equilibrium. Assuming that TDGs are in dynamical equilibrium, we find that the ratio of dynamical mass to baryonic mass is consistent with one, implying that TDGs are devoid of dark matter. This is in line with the results of numerical simulations where tidal forces effectively segregate dark matter in the halo from baryonic matter i...

  4. HAWAIIAN OCEAN MIXING EXPERIMENT (HOME): FARFIELD PROGRAM HAWAIIAN TIDAL ENERGY BUDGET

    E-Print Network [OSTI]

    Dushaw, Brian

    HAWAIIAN OCEAN MIXING EXPERIMENT (HOME): FARFIELD PROGRAM HAWAIIAN TIDAL ENERGY BUDGET Principal). This tidal energy budget will determine limits on the energy dissipated in the nearfield of the Hawaiian and ocean acoustic tomography have brought a new dimension to the subject. We propose to measure the energy

  5. JULY 2005 1 An estimate of tidal energy lost to turbulence at the Hawaiian Ridge

    E-Print Network [OSTI]

    Klymak, Jody M.

    JULY 2005 1 An estimate of tidal energy lost to turbulence at the Hawaiian Ridge JODY M. KLYMAK1 of the ridge, giving an estimate of 3±1.5 GW of tidal energy lost to turbulence dissipation within 60 km relation- ship between the energy in the semi-diurnal internal tide (E) and the depth

  6. ORNL/TM-2012/301 Experimental Test Plan DOE Tidal

    E-Print Network [OSTI]

    Siefert, Chris

    ORNL/TM-2012/301 Experimental Test Plan ­ DOE Tidal And River Reference Turbines August 2012 Test Plan ­ DOE Tidal and River Reference Turbines Vincent S. Neary1 Craig Hill2 Leonardo P. Chamorro 2 16, 2012 Prepared for: Wind and Water Power Technologies Program Office of Energy Efficiency

  7. time scale observed in some close binary systems (19), and tidal dissipation (20)

    E-Print Network [OSTI]

    Stanley, H. Eugene

    time scale observed in some close binary systems (19), and tidal dissipation (20) may also cause). At this stage, the core of star A undergoes collapse, and the residual nuclear fuel is ignited to power aware that both tidal and general relativistic ef- fects will be important in this system

  8. Post Doctoral (OR Research Engineer) fellowship Distributed Control of a Tidal Farm

    E-Print Network [OSTI]

    Condat, Laurent

    Post Doctoral (OR Research Engineer) fellowship Distributed Control of a Tidal Farm Context on con- trol systems and power systems) and ALSTOM-ocean (world- wide leader in turbines construction and operating a tidal farm of 30-200 MW. Successful applicants will work at GIPSA-lab (Grenoble) (http

  9. Numerical and Analytical Estimates of M2 Tidal Conversion at Steep Oceanic Ridges EMANUELE DI LORENZO

    E-Print Network [OSTI]

    Young, William R.

    of mechanical energy required to mix the global ocean (Garrett and St. Laurent 2002). Tidal forces perform aboutNumerical and Analytical Estimates of M2 Tidal Conversion at Steep Oceanic Ridges EMANUELE DI) ABSTRACT Numerical calculations of the rate at which energy is converted from the external to internal

  10. Can Earth's rotation and tidal despinning drive plate tectonics? Federica Riguzzi a,c,

    E-Print Network [OSTI]

    Can Earth's rotation and tidal despinning drive plate tectonics? Federica Riguzzi a,c, , Giuliano January 2009 Accepted 10 June 2009 Available online xxxx Keywords: Plate tectonics Earth's rotation Tidal despinning Earth's energy budget We re-evaluate the possibility that Earth's rotation contributes to plate

  11. Vibrio litoralis sp. nov., isolated from a Yellow Sea tidal flat in Korea

    E-Print Network [OSTI]

    Bae, Jin-Woo

    Vibrio litoralis sp. nov., isolated from a Yellow Sea tidal flat in Korea Young-Do Nam,1,2 Ho-negative, facultatively anaerobic bacterial strains, MANO22DT and MANO22P, were isolated from a tidal flat area of Dae and energy sources. A phylogenetic analysis based on 16S rRNA gene sequences revealed that the strains belong

  12. Expressions for Tidal Conversion at Seafloor Topography using Physical-Space Integrals

    E-Print Network [OSTI]

    Schörghofer, Norbert

    Expressions for Tidal Conversion at Seafloor Topography using Physical-Space Integrals Norbert and a potential source of the required mechanical energy is the generation and breaking of internal gravity waves (Egbert and Ray, 2000; Ledwell et al., 2000). Tidal dissipation has long been recognized as important

  13. Laboratory studies of eddy structures and exchange processes through tidal inlets 

    E-Print Network [OSTI]

    Nicolau del Roure, Francisco

    2009-06-02

    , Germany, which has the capability to generate a sinusoidal flow that simulates a series of tidal cycles. A set of idealized inlets were arranged in the tank, and by varying the tidal period and the maximum velocity, three different types of life...

  14. Cross-shore sediment transport and the equilibrium morphology of mudflats under tidal currents

    E-Print Network [OSTI]

    Hogg, Andrew

    Cross-shore sediment transport and the equilibrium morphology of mudflats under tidal currents D of suspended sediment transport under cross-shore tidal currents on an intertidal mudflat. We employ a Lagrangian formulation to obtain periodic solutions for the sediment transport over idealized bathymetries

  15. Cross-shore suspended sediment transport under tidal currents Andrew J. Hogg1

    E-Print Network [OSTI]

    Hogg, Andrew

    Cross-shore suspended sediment transport under tidal currents Andrew J. Hogg1 and David Pritchard2-mail: david@bpi.cam.ac.uk Abstract The transport of sediment over an intertidal mudflat by a cross-shore tidal-layer approximation. It is found that the sediment transport comprises advection with the mean flow, deposition

  16. Chapter 5 -Sediment, Nutrient, and Vegetation Trends Along the Tidal, Forested Pocomoke

    E-Print Network [OSTI]

    Chapter 5 - Sediment, Nutrient, and Vegetation Trends Along the Tidal, Forested Pocomoke River-tidal upstream sites. Floodplain sediments in the past W.H. Conner, T.W. Doyle, and K.W. Krauss (eds.), Ecology]). These sediments overlie hundreds of meters of Tertiary (2-65 mybp) greensands and clay- silt. The Tertiary

  17. Integration of Wave and Tidal Power into the Haida Gwaii Electrical Grid

    E-Print Network [OSTI]

    Victoria, University of

    Integration of Wave and Tidal Power into the Haida Gwaii Electrical Grid by Susan Margot Boronowski Committee Integration of Wave and Tidal Power into the Haida Gwaii Electrical Grid by Susan Margot only be practical at power penetration levels less than 20%. #12;iv Table of Contents Supervisory

  18. Scaling laws to quantify tidal dissipation in star-planet systems

    E-Print Network [OSTI]

    Auclair-Desrotour, Pierre; Poncin-Lafitte, Christophe Le

    2015-01-01

    Planetary systems evolve over secular time scales. One of the key mechanisms that drive this evolution is tidal dissipation. Submitted to tides, stellar and planetary fluid layers do not behave like rocky ones. Indeed, they are the place of resonant gravito-inertial waves. Therefore, tidal dissipation in fluid bodies strongly depends on the excitation frequency while this dependence is smooth in solid ones. Thus, the impact of the internal structure of celestial bodies must be taken into account when studying tidal dynamics. The purpose of this work is to present a local model of tidal gravito-inertial waves allowing us to quantify analytically the internal dissipation due to viscous friction and thermal diffusion, and to study the properties of the resonant frequency spectrum of the dissipated energy. We derive from this model scaling laws characterizing tidal dissipation as a function of fluid parameters (rotation, stratification, diffusivities) and discuss them in the context of star-planet systems.

  19. Modeling Tidal Freshwater Marsh Sustainability in the Sacramento–San Joaquin Delta Under a Broad Suite of Potential Future Scenarios

    E-Print Network [OSTI]

    Swanson, Kathleen M.; Drexler, Judith Z.; Fuller, Christopher C.; Schoellhamer, David H.

    2015-01-01

    tidal freshwater marsh sites in the Delta Site name Coordinates Area (ha) Elevation above MSL (cm) Salinity regime Energy

  20. Modeling Tidal Freshwater Marsh Sustainability in the Sacramento–San Joaquin Delta Under a Broad Suite of Potential Future Scenarios

    E-Print Network [OSTI]

    Swanson, Kathleen M.; Drexler, Judith Z.; Fuller, Christopher C.; Schoellhamer, David H.

    2015-01-01

    Table 1 Location and basic characteristics of tidal freshwater marsh sites in the Delta Site name Coordinates

  1. Tidal Residual Eddies and their Effect on Water Exchange in Puget Sound

    SciTech Connect (OSTI)

    Yang, Zhaoqing; Wang, Taiping

    2013-08-30

    Tidal residual eddies are one of the important hydrodynamic features in tidally dominant estuaries and coastal bays, and they could have significant effects on water exchange in a tidal system. This paper presents a modeling study of tides and tidal residual eddies in Puget Sound, a tidally dominant fjord-like estuary in the Pacific Northwest coast, using a three-dimensional finite-volume coastal ocean model. Mechanisms of vorticity generation and asymmetric distribution patterns around an island/headland were analyzed using the dynamic vorticity transfer approach and numerical experiments. Model results of Puget Sound show that a number of large twin tidal residual eddies exist in the Admiralty Inlet because of the presence of major headlands in the inlet. Simulated residual vorticities near the major headlands indicate that the clockwise tidal residual eddy (negative vorticity) is generally stronger than the anticlockwise eddy (positive vorticity) because of the effect of Coriolis force. The effect of tidal residual eddies on water exchange in Puget Sound and its sub-basins were evaluated by simulations of dye transport. It was found that the strong transverse variability of residual currents in the Admiralty Inlet results in a dominant seaward transport along the eastern shore and a dominant landward transport along the western shore of the Inlet. A similar transport pattern in Hood Canal is caused by the presence of tidal residual eddies near the entrance of the canal. Model results show that tidal residual currents in Whidbey Basin are small in comparison to other sub-basins. A large clockwise residual circulation is formed around Vashon Island near entrance of South Sound, which can potentially constrain the water exchange between the Central Basin and South Sound.

  2. Internal wave and boundary current generation by tidal flow over topography Amadeus Dettner, Harry L. Swinney, and M. S. Paoletti

    E-Print Network [OSTI]

    to characterize the conversion of tidal energy to radiated internal wave power. Whether the hydrostatic ( , shape)/SIW, where Ptide is the effective tidal power that interacts with the topography, and /8 of the oceans. Therefore, it is useful to measure the total power PIW converted from barotropic tidal motions

  3. Estimation vido haute frquence de la topographie inter-tidale d'une plage sableuse : application la

    E-Print Network [OSTI]

    Estimation vidéo haute fréquence de la topographie inter- tidale d'une plage sableuse : application outil vidéo d'estimation haute fréquence de la topographie inter-tidale. Cet outil est basé sur le suivi : We present a tool to estimate inter-tidal topography using video images. This tool is based

  4. Tidal front affects the size of prey used by a top marine predator, the short-tailed shearwater (Puffinus tenuirostris)

    E-Print Network [OSTI]

    Tidal front affects the size of prey used by a top marine predator, the short-tailed shearwater densities of small euphausiids were associated with a tidal front on the north side of Akutan Pass. At most sites elsewhere in the Bering Sea, away from tidal fronts, shearwaters selected larger (14.2­20.1 mm

  5. FY 2012 DOE Agency Financial Report | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    in FY 2012 include: the first electric grid-connected tidal energy project off the coast of Maine a new approach to sea water desalination that could lower the costs of water...

  6. OPTICAL DISCOVERY OF PROBABLE STELLAR TIDAL DISRUPTION FLARES

    SciTech Connect (OSTI)

    Van Velzen, Sjoert; Farrar, Glennys R. [Center for Cosmology and Particle Physics, New York University, NY 10003 (United States); Gezari, Suvi [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States); Morrell, Nidia [Carnegie Observatories, Las Campanas Observatory, Casillas 601, La Serena (Chile); Zaritsky, Dennis [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Oestman, Linda [Institut de Fisica d'Altes Energies, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Barcelona) (Spain); Smith, Mathew [Department of Mathematics and Applied Mathematics, University of Cape Town, Rondebosch, 7701 (South Africa); Gelfand, Joseph [New York University-Abu Dhabi, Abu Dhabi (United Arab Emirates); Drake, Andrew J., E-mail: s.vanvelzen@astro.ru.nl [Center for Advance Computing Research, California Institute of Technology, Pasadena, CA 91225 (United States)

    2011-11-10

    Using archival Sloan Digital Sky Survey (SDSS) multi-epoch imaging data (Stripe 82), we have searched for the tidal disruption of stars by supermassive black holes in non-active galaxies. Two candidate tidal disruption events (TDEs) are identified. The TDE flares have optical blackbody temperatures of 2 Multiplication-Sign 10{sup 4} K and observed peak luminosities of M{sub g} = -18.3 and -20.4 ({nu}L{sub {nu}} = 5 Multiplication-Sign 10{sup 42}, 4 Multiplication-Sign 10{sup 43} erg s{sup -1}, in the rest frame); their cooling rates are very low, qualitatively consistent with expectations for tidal disruption flares. The properties of the TDE candidates are examined using (1) SDSS imaging to compare them to other flares observed in the search, (2) UV emission measured by GALEX, and (3) spectra of the hosts and of one of the flares. Our pipeline excludes optically identifiable AGN hosts, and our variability monitoring over nine years provides strong evidence that these are not flares in hidden AGNs. The spectra and color evolution of the flares are unlike any SN observed to date, their strong late-time UV emission is particularly distinctive, and they are nuclear at high resolution arguing against these being first cases of a previously unobserved class of SNe or more extreme examples of known SN types. Taken together, the observed properties are difficult to reconcile with an SN or an AGN-flare explanation, although an entirely new process specific to the inner few hundred parsecs of non-active galaxies cannot be excluded. Based on our observed rate, we infer that hundreds or thousands of TDEs will be present in current and next-generation optical synoptic surveys. Using the approach outlined here, a TDE candidate sample with O(1) purity can be selected using geometric resolution and host and flare color alone, demonstrating that a campaign to create a large sample of TDEs, with immediate and detailed multi-wavelength follow-up, is feasible. A by-product of this work is quantification of the power spectrum of extreme flares in AGNs.

  7. Circularization of Tidally Disrupted Stars around Spinning Supermassive Black Holes

    E-Print Network [OSTI]

    Hayasaki, Kimitake; Loeb, Abraham

    2015-01-01

    We study the circularization of tidally disrupted stars on bound orbits around spinning supermassive black holes by performing three-dimensional smoothed particle hydrodynamic simulations with Post-Newtonian corrections. Our simulations reveal that debris circularization depends sensitively on the efficiency of radiative cooling. There are two stages in debris circularization if radiative cooling is inefficient: first, the stellar debris streams self-intersect due to relativistic apsidal precession; shocks at the intersection points thermalize orbital energy and the debris forms a geometrically thick, ring-like structure around the black hole. The ring rapidly spreads via viscous diffusion, leading to the formation of a geometrically thick accretion disk. In contrast, if radiative cooling is efficient, the stellar debris circularizes due to self-intersection shocks and forms a geometrically thin ring-like structure. In this case, the dissipated energy can be emitted during debris circularization as a precurso...

  8. A 22 Degree Tidal Tail for Palomar 5

    E-Print Network [OSTI]

    C. J. Grillmair; O. Dionatos

    2006-03-02

    Using Data Release 4 of the Sloan Digital Sky Survey, we have applied an optimal contrast, matched filter technique to trace the trailing tidal tail of the globular cluster Palomar 5 to a distance of 18.5 degrees from the center of the cluster. This more than doubles the total known length of the tail to some 22 degrees on the sky. Based on a simple model of the Galaxy, we find that the stream's orientation on the sky is consistent at the 1.7 sigma level with existing proper motion measurements. We find that a spherical Galactic halo is adequate to model the stream over its currently known length, and we are able to place new constraints on the current space motion of the cluster.

  9. Tidal Charged Black Holes as Particle Accelerators to Arbitrarily High Energy

    E-Print Network [OSTI]

    Pradhan, Parthapratim

    2014-01-01

    We show that Randall Sundrum tidal charged spherically symmetric vacuum brane black holes could be act as a particle accelerator with ultrahigh center-of-mass energy in the limiting case of \\emph{ maximal black hole tidal charge}. For non-extremal Randall Sundrum tidal charged black hole, the center-of-mass energy is finite. While for maximally Randall Sundrum tidal charged black hole, the center-of-mass energy is \\emph{infinite}. We have also derived the center-of-mass energy at ISCO(Innermost Stable Circular Orbit) or LSCO(Last Stable Circular Orbit) or MSCO(Marginally Stable Circular Orbit) and MBCO (Marginally Bound Circular Orbit) for maximally Randall Sundrum tidal charged black hole. We show visually the differences between Reissner-Nordstr{\\o}m black hole and Randall Sundrum tidal charged BH. We have found that for maximally Randall Sundrum tidal charged black hole the center-of-mass energy is satisfied the following inequality: $E_{cm}\\mid_{r_{+}}>E_{cm}\\mid_{r_{mb}}>E_{cm}\\mid_{r_{ISCO}}$ i.e. $E_{c...

  10. Tidal Charged Black Holes as Particle Accelerators to Arbitrarily High Energy

    E-Print Network [OSTI]

    Parthapratim Pradhan

    2014-12-28

    We show that Randall Sundrum tidal charged spherically symmetric vacuum brane black holes could be act as a particle accelerator with ultrahigh center-of-mass energy in the limiting case of \\emph{ maximal black hole tidal charge}. For non-extremal Randall Sundrum tidal charged black hole, the center-of-mass energy is finite. While for maximally Randall Sundrum tidal charged black hole, the center-of-mass energy is \\emph{infinite}. We have also derived the center-of-mass energy at ISCO(Innermost Stable Circular Orbit) or LSCO(Last Stable Circular Orbit) or MSCO(Marginally Stable Circular Orbit) and MBCO (Marginally Bound Circular Orbit) for maximally Randall Sundrum tidal charged black hole. We show visually the differences between Reissner-Nordstr{\\o}m black hole and Randall Sundrum tidal charged BH. We have found that for maximally Randall Sundrum tidal charged black hole the center-of-mass energy is satisfied the following inequality: $E_{cm}\\mid_{r_{+}}>E_{cm}\\mid_{r_{mb}}>E_{cm}\\mid_{r_{ISCO}}$ i.e. $E_{cm}\\mid_{r_{+} = \\frac{M}{M_{p}^2}}: E_{cm}\\mid_{r_{mb} = \\left(\\frac{3+\\sqrt{5}}{2}\\right)\\frac{M}{M_{p}^2}}:E_{cm}\\mid_{r_{ISCO} = 4\\frac{M}{M_{p}^2}} = \\infty: 3.23 : 2.6$. Which is exactly \\emph{similar} to the spherically symmetric extreme Reissner-Nordstr\\"{o}m black hole.}

  11. Technological cost%3CU%2B2010%3Ereduction pathways for axial%3CU%2B2010%3Eflow turbines in the marine hydrokinetic environment.

    SciTech Connect (OSTI)

    Laird, Daniel L.; Johnson, Erick L.; Ochs, Margaret Ellen; Boren, Blake

    2013-05-01

    This report considers and prioritizes potential technical costreduction pathways for axialflow turbines designed for tidal, river, and ocean current resources. This report focuses on technical research and development costreduction pathways related to the device technology rather than environmental monitoring or permitting opportunities. Three sources of information were utilized to understand current cost drivers and develop a list of potential costreduction pathways: a literature review of technical work related to axialflow turbines, the U.S. Department of Energy Reference Model effort, and informal webinars and other targeted interactions with industry developers. Data from these various information sources were aggregated and prioritized with respect to potential impact on the lifetime levelized cost of energy. The four most promising costreduction pathways include structural design optimization; improved deployment, maintenance, and recovery; system simplicity and reliability; and array optimization.

  12. Multiscale heterogeneity characterization of tidal channel, tidal delta and foreshore facies, Almond Formation outcrops, Rock Springs uplift, Wyoming

    SciTech Connect (OSTI)

    Schatzinger, R.A.; Tomutsa, L.

    1997-08-01

    In order to accurately predict fluid flow within a reservoir, variability in the rock properties at all scales relevant to the specific depositional environment needs to be taken into account. The present work describes rock variability at scales from hundreds of meters (facies level) to millimeters (laminae) based on outcrop studies of the Almond Formation. Tidal channel, tidal delta and foreshore facies were sampled on the eastern flank of the Rock Springs uplift, southeast of Rock Springs, Wyoming. The Almond Fm. was deposited as part of a mesotidal Upper Cretaceous transgressive systems tract within the greater Green River Basin. Bedding style, lithology, lateral extent of beds of bedsets, bed thickness, amount and distribution of depositional clay matrix, bioturbation and grain sorting provide controls on sandstone properties that may vary more than an order of magnitude within and between depositional facies in outcrops of the Almond Formation. These features can be mapped on the scale of an outcrop. The products of diagenesis such as the relative timing of carbonate cement, scale of cemented zones, continuity of cemented zones, selectively leached framework grains, lateral variability of compaction of sedimentary rock fragments, and the resultant pore structure play an equally important, although less predictable role in determining rock property heterogeneity. A knowledge of the spatial distribution of the products of diagenesis such as calcite cement or compaction is critical to modeling variation even within a single facies in the Almond Fin. because diagenesis can enhance or reduce primary (depositional) rock property heterogeneity. Application of outcrop heterogeneity models to the subsurface is greatly hindered by differences in diagenesis between the two settings. The measurements upon which this study is based were performed both on drilled outcrop plugs and on blocks.

  13. hydrokinetic | OpenEI Community

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-EnhancingEtGeorgia:Illinois:WizardYatescloud Home Dc's pictureenergygrid

  14. Marine & Hydrokinetic Technologies (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2011-07-01

    This document described the U.S. Department of Energy's Water Power Program efforts to promote the development and deployment of advanced water power devices.

  15. Hydrokinetic Laboratory | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource History View NewGuam: Energyarea,MagazineTechnologies

  16. Tidal energy effects of dark matter halos on early-type galaxies

    E-Print Network [OSTI]

    Valentinuzzi, T; D'Onofrio, M

    2010-01-01

    Tidal interactions between neighboring objects span across the whole admissible range of lengths in nature: from, say, atoms to clusters of galaxies i.e. from micro to macrocosms. According to current cosmological theories, galaxies are embedded within massive non-baryonic dark matter (DM) halos, which affects their formation and evolution. It is therefore highly rewarding to understand the role of tidal interaction between the dark and luminous matter in galaxies. The current investigation is devoted to Early-Type Galaxies (ETGs), looking in particular at the possibility of establishing whether the tidal interaction of the DM halo with the luminous baryonic component may be at the origin of the so-called "tilt" of the Fundamental Plane (FP). The extension of the tensor virial theorem to two-component matter distributions implies the calculation of the self potential energy due to a selected subsystem, and the tidal potential energy induced by the other one. The additional assumption of homeoidally striated d...

  17. How does vegetation affect sedimentation on tidal marshes? Investigating particle capture and hydrodynamic controls

    E-Print Network [OSTI]

    Mudd, Simon Marius

    How does vegetation affect sedimentation on tidal marshes? Investigating particle capture stems, or enhanced settling due to a reduction in turbulent kinetic energy within flows through kinetic energy in the fertilized canopy. Our newly developed models of biologically mediated sedimentation

  18. Sudden increase in tidal response linked to calving and acceleration at a large Greenland outlet glacier

    E-Print Network [OSTI]

    de Juan, J.; Elosegui, P.; Nettles, M.; Larsen, T. B.; Davis, J. L.; Hamilton, Gordon S.; Stearns, Leigh; Anderson, M. L.; Ekstrom, G.; Ahlstrom, A. P.; Stenseng, L.; Khan, S. A.; Forsberg, R.

    2010-06-23

    [1] Large calving events at Greenland's largest outlet glaciers are associated with glacial earthquakes and near-instantaneous increases in glacier flow speed. At some glaciers and ice streams, flow is also modulated in a regular way by ocean tidal...

  19. Saltwater Incursion into Micro Tidal Wetlands: Case Studies from Matagorda, Texas and Humacao, Puerto Rico 

    E-Print Network [OSTI]

    Colon, Ricardo J.

    2013-08-27

    Global climate change threatens the survival of microtidal wetlands by altering fundamental hydrological aspects such as precipitation patterns and tidal exchange. The combination of these stressors results in increased flooding period and soil...

  20. Status of Wave and Tidal Power Technologies for the United States

    SciTech Connect (OSTI)

    Musial, W.

    2008-08-01

    This paper presents the status of marine applications for renewable energy as of 2008 from a U.S. perspective. Technologies examined include wave, tidal, and ocean current energy extraction devices.

  1. Maine Project Takes Historic Step Forward in U.S. Tidal Energy...

    Energy Savers [EERE]

    contracts will be in place for 20 years -- making them the first long-term tidal energy power purchase agreements in the United States. The implications of these agreements are...

  2. Dispersion Mechanisms of a Tidal River Junction in the Sacramento–San Joaquin Delta, California

    E-Print Network [OSTI]

    Gleichauf, Karla T.; Wolfram, Phillip J.; Monsen, Nancy E.; Fringer, Oliver B.; Monismith, Stephen G.

    2014-01-01

    a Tidal River Junction in the Sacramento–San Joaquin Delta,networks, such as in the Sacramento–San Joaquin River Delta,transport and fate in the Sacramento–San Joaquin delta using

  3. Microsoft Word - RM1_Tidal Turbine_NREL Bir, Lawson, Li_2011...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Arctic Engineering OMAE2011 June 19-24, 20111, Rotterdam, the Netherland OMAE2011-50063 STRUCTURAL DESIGN OF A HORIZONTAL-AXIS TIDAL CURRENT TURBINE COMPOSITE BLADE ABSTRACT This...

  4. ORGANIC MATTER DISTRIBUTION AND TURNOVER ALONG A GRADIENT FROM FOREST TO TIDAL CREEK

    E-Print Network [OSTI]

    Lawrence, Deborah

    i ORGANIC MATTER DISTRIBUTION AND TURNOVER ALONG A GRADIENT FROM FOREST TO TIDAL CREEK A Thesis. A nested plot design was used to harvest vegetation, obtain soil cores, and collect quantitative data... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .18 Qualitative Vegetation Analysis

  5. Measurement of the rate of stellar tidal disruption flares

    SciTech Connect (OSTI)

    Van Velzen, Sjoert

    2014-09-01

    We report an observational estimate of the rate of stellar tidal disruption flares (TDFs) in inactive galaxies based on a successful search for these events among transients in galaxies using archival Sloan Digital Sky Survey (SDSS) multi-epoch imaging data (Stripe 82). This search yielded 186 nuclear flares in galaxies, 2 of which are excellent TDF candidates. Because of the systematic nature of the search, the very large number of galaxies, the long time of observation, and the fact that non-TDFs were excluded without resorting to assumptions about TDF characteristics, this study provides an unparalleled opportunity to measure the TDF rate. To compute the rate of optical stellar tidal disruption events, we simulate our entire pipeline to obtain the efficiency of detection. The rate depends on the light curves of TDFs, which are presently still poorly constrained. Using only the observed part of the SDSS light curves gives a model-independent upper limit to the optical TDF rate, N-dot <2×10{sup ?4} yr{sup ?1} galaxy{sup ?1} (90% CL), under the assumption that the SDSS TDFs are representative examples. We develop three empirical models of the light curves based on the two SDSS light curves and two more recent and better-sampled Pan-STARRS TDF light curves, leading to our best estimate of the rate: N-dot {sub TDF}=(1.5--2.0){sub ?1.3}{sup +2.7}×10{sup ?5} yr{sup ?1} galaxy{sup ?1}. We explore the modeling uncertainties by considering two theoretically motivated light curve models, as well as two different relationships between black hole mass and galaxy luminosity, and two different treatments of the cutoff in the visibility of TDFs at large M {sub BH}. From this we conclude that these sources of uncertainty are not significantly larger than the statistical ones. Our results are applicable for galaxies hosting black holes with mass in the range of a few 10{sup 6}-10{sup 8} M {sub ?}, and translates to a volumetric TDF rate of (4-8) × 10{sup –8±0.4} yr{sup –1} Mpc{sup –3}, with the statistical uncertainty in the exponent.

  6. Fourier and autocorrelation analysis of estuarine tidal rhythmites, lower Breathitt Formation (Pennsylvania), eastern Kentucky, USA

    SciTech Connect (OSTI)

    Martino, R.L.; Sanderson, D.D. (Marshall Univ., Huntington, WV (United States))

    1993-01-01

    Outcrops of the Pennsylvanian Breathitt Formation in eastern Kentucky reveal a rhythmic pattern of siliciclastic sedimentation in a marginal marine coastal setting. A 15-23 m thick stratigraphic interval of thinly interbedded, fine sandstone and shale displays tidally generated features such as flaser and wavy current ripple bedding, bipolar paleocurrents, and cyclic thickening and thinning of mud-draped sandstone layers. A statistical analysis of sand layer thickness was carried out using shale partings as bounding surfaces for the individual sand units. Fourier and autocorrelation analyses were performed on two vertical sequences containing a total of over 2,100 layers. The results reveal the presence of four cycles of thickness variation. First-order cycles consist of alternating thick-thin sand layers. These daily couplets may reflect unequal flood and ebb currents during a single tidal cycle or dominant and subordinate tidal deposits in an ebb or flood dominated semidiurnal or mixed system. Second-order cycles typically consist of 11-14 sand layers and reflect spring-neap variations in tidal range and current velocities. Third-order cycles are usually composed of 24-35 layers and are formed in response to monthly variations in tidal range resulting from the ellipticity of the moon's orbit. Fourth-order cycles generally contain about 150 layers (range, 100-166) and were caused by seasonal maxima in tidal range associated with the solstice (winter, summer) and seasonal minima associated with the equinox (spring, fall).

  7. FAINT TIDAL FEATURES IN GALAXIES WITHIN THE CANADA-FRANCE-HAWAII TELESCOPE LEGACY SURVEY WIDE FIELDS

    SciTech Connect (OSTI)

    Atkinson, Adam M.; Abraham, Roberto G.; Ferguson, Annette M. N.

    2013-03-01

    We present an analysis of the detectability of faint tidal features in galaxies from the wide-field component of the Canada-France-Hawaii Telescope Legacy Survey. Our sample consists of 1781 luminous (M{sub r{sup '}}<-19.3 mag) galaxies in the magnitude range 15.5 mag < r' < 17 mag and in the redshift range 0.04 < z < 0.2. Although we have classified tidal features according to their morphology (e.g., streams, shells, and tails), we do not attempt to interpret them in terms of their physical origin (e.g., major versus minor merger debris). Instead, we provide a catalog that is intended to provide raw material for future investigations which will probe the nature of low surface brightness substructure around galaxies. We find that around 12% of the galaxies in our sample show clear tidal features at the highest confidence level. This fraction rises to about 18% if we include systems with convincing, albeit weaker tidal features, and to 26% if we include systems with more marginal features that may or may not be tidal in origin. These proportions are a strong function of rest-frame color and of stellar mass. Linear features, shells, and fans are much more likely to occur in massive galaxies with stellar masses >10{sup 10.5} M {sub Sun }, and red galaxies are twice as likely to show tidal features than are blue galaxies.

  8. A Modeling Study of the Potential Water Quality Impacts from In-Stream Tidal Energy Extraction

    SciTech Connect (OSTI)

    Wang, Taiping; Yang, Zhaoqing; Copping, Andrea E.

    2013-11-09

    To assess the effects of tidal energy extraction on water quality in a simplified estuarine system, which consists of a tidal bay connected to the coastal ocean through a narrow channel where energy is extracted using in-stream tidal turbines, a three-dimensional coastal ocean model with built-in tidal turbine and water quality modules was applied. The effects of tidal energy extraction on water quality were examined for two energy extraction scenarios as compared with the baseline condition. It was found, in general, that the environmental impacts associated with energy extraction depend highly on the amount of power extracted from the system. Model results indicate that, as a result of energy extraction from the channel, the competition between decreased flushing rates in the bay and increased vertical mixing in the channel directly affects water quality responses in the bay. The decreased flushing rates tend to cause a stronger but negative impact on water quality. On the other hand, the increase of vertical mixing could lead to higher bottom dissolved oxygen at times. As the first modeling effort directly aimed at examining the impacts of tidal energy extraction on estuarine water quality, this study demonstrates that numerical models can serve as a very useful tool for this purpose. However, more careful efforts are warranted to address system-specific environmental issues in real-world, complex estuarine systems.

  9. Gravitational self-force corrections to two-body tidal interactions and the effective one-body formalism

    E-Print Network [OSTI]

    Donato Bini; Thibault Damour

    2014-09-24

    Tidal interactions have a significant influence on the late dynamics of compact binary systems, which constitute the prime targets of the upcoming network of gravitational-wave detectors. We refine the theoretical description of tidal interactions (hitherto known only to the second post-Newtonian level) by extending our recently developed analytic self-force formalism, for extreme mass-ratio binary systems, to the computation of several tidal invariants. Specifically, we compute, to linear order in the mass ratio and to the 7.5$^{\\rm th}$ post-Newtonian order, the following tidal invariants: the square and the cube of the gravitoelectric quadrupolar tidal tensor, the square of the gravitomagnetic quadrupolar tidal tensor, and the square of the gravitoelectric octupolar tidal tensor. Our high-accuracy analytic results are compared to recent numerical self-force tidal data by Dolan et al. \\cite{Dolan:2014pja}, and, notably, provide an analytic understanding of the light ring asymptotic behavior found by them. We transcribe our kinematical tidal-invariant results in the more dynamically significant effective one-body description of the tidal interaction energy. By combining, in a synergetic manner, analytical and numerical results, we provide simple, accurate analytic representations of the global, strong-field behavior of the gravitoelectric quadrupolar tidal factor. A striking finding is that the linear-in-mass-ratio piece in the latter tidal factor changes sign in the strong-field domain, to become negative (while its previously known second post-Newtonian approximant was always positive). We, however, argue that this will be more than compensated by a probable fast growth, in the strong-field domain, of the nonlinear-in-mass-ratio contributions in the tidal factor.

  10. Comparing the escape dynamics in tidally limited star cluster models

    E-Print Network [OSTI]

    Euaggelos E. Zotos

    2015-08-21

    The aim of this work is to compare the orbital dynamics in three different models describing the properties of a star cluster rotating around its parent galaxy in a circular orbit. In particular, we use the isochrone and the Hernquist potentials to model the spherically symmetric star cluster and we compare our results with the corresponding ones of a previous work in which the Plummer model was applied for the same purpose. Our analysis takes place both in the configuration $(x,y)$ and in the phase $(x,\\dot{x})$ space in order to elucidate the escape process as well as the overall orbital properties of the tidally limited star cluster. We restrict our investigation into two dimensions and we conduct a thorough numerical analysis distinguishing between ordered and chaotic orbits as well as between trapped and escaping orbits, considering only unbounded motion for several energy levels above the critical escape energy. It is of particular interest to determine the escape basins towards the two exit channels (near the Lagrangian points $L_1$ and $L_2$) and relate them with the corresponding escape times of the orbits.

  11. "Circularization" vs. Accretion -- What Powers Tidal Disruption Events?

    E-Print Network [OSTI]

    Piran, Tsvi; Krolik, Julian; Cheng, Roseanne M; Shiokawa, Hotaka

    2015-01-01

    A tidal disruption event (TDE) takes place when a star passes near enough to a massive black hole to be disrupted. About half the star's matter is given elliptical trajectories with large apocenter distances, the other half is unbound. To "circularize", i.e., to form an accretion flow, the bound matter must lose a significant amount of energy, with the actual amount depending on the characteristic scale of the flow measured in units of the black hole's gravitational radius (~ 10^{51} (R/1000R_g)^{-1} erg). Recent numerical simulations (Shiokawa et al., 2015) have revealed that the circularization scale is close to the scale of the most-bound initial orbits, ~ 10^3 M_{BH,6.5}^{-2/3} R_g ~ 10^{15} M_{BH,6.5}^{1/3} cm from the black hole, and the corresponding circularization energy dissipation rate is $\\sim 10^{44} M_{BH,6.5}^{-1/6}$~erg/s. We suggest that the energy liberated during circularization, rather then energy liberated by accretion onto the black hole, powers the observed optical TDE candidates (e.g.A...

  12. Comparing the escape dynamics in tidally limited star cluster models

    E-Print Network [OSTI]

    Zotos, Euaggelos E

    2015-01-01

    The aim of this work is to compare the orbital dynamics in three different models describing the properties of a star cluster rotating around its parent galaxy in a circular orbit. In particular, we use the isochrone and the Hernquist potentials to model the spherically symmetric star cluster and we compare our results with the corresponding ones of a previous work in which the Plummer model was applied for the same purpose. Our analysis takes place both in the configuration $(x,y)$ and in the phase $(x,\\dot{x})$ space in order to elucidate the escape process as well as the overall orbital properties of the tidally limited star cluster. We restrict our investigation into two dimensions and we conduct a thorough numerical analysis distinguishing between ordered and chaotic orbits as well as between trapped and escaping orbits, considering only unbounded motion for several energy levels above the critical escape energy. It is of particular interest to determine the escape basins towards the two exit channels (n...

  13. Tidal Downsizing Model. IV. Destructive feedback in planets

    E-Print Network [OSTI]

    Nayakshin, Sergei

    2015-01-01

    I argue that feedback is as important to formation of planets as it is to formation of stars and galaxies. Energy released by massive solid cores puffs up pre-collapse gas giant planets, making them vulnerable to tidal disruptions by their host stars. I find that feedback is the ultimate reason for some of the most robust properties of the observed exoplanet populations: the rarity of gas giants at all separations from $\\sim 0.1$ to $\\sim 100$~AU, the abundance of $\\sim 10 M_\\oplus$ cores but dearth of planets more massive than $\\sim 20 M_\\oplus$. Feedback effects can also explain (i) rapid assembly of massive cores at large separations as needed for Uranus, Neptune and the suspected HL Tau planets; (ii) the small core in Jupiter yet large cores in Uranus and Neptune; (iii) the existence of rare "metal monster" planets such as CoRoT-20b, a gas giant made of heavy elements by up to $\\sim 50$\\%.

  14. WATER TRAPPING ON TIDALLY LOCKED TERRESTRIAL PLANETS REQUIRES SPECIAL CONDITIONS

    SciTech Connect (OSTI)

    Yang, Jun; Abbot, Dorian S.; Liu, Yonggang; Hu, Yongyun

    2014-12-01

    Surface liquid water is essential for standard planetary habitability. Calculations of atmospheric circulation on tidally locked planets around M stars suggest that this peculiar orbital configuration lends itself to the trapping of large amounts of water in kilometers-thick ice on the night side, potentially removing all liquid water from the day side where photosynthesis is possible. We study this problem using a global climate model including coupled atmosphere, ocean, land, and sea ice components as well as a continental ice sheet model driven by the climate model output. For a waterworld, we find that surface winds transport sea ice toward the day side and the ocean carries heat toward the night side. As a result, nightside sea ice remains O(10 m) thick and nightside water trapping is insignificant. If a planet has large continents on its night side, they can grow ice sheets O(1000 m) thick if the geothermal heat flux is similar to Earth's or smaller. Planets with a water complement similar to Earth's would therefore experience a large decrease in sea level when plate tectonics drives their continents onto the night side, but would not experience complete dayside dessiccation. Only planets with a geothermal heat flux lower than Earth's, much of their surface covered by continents, and a surface water reservoir O(10%) of Earth's would be susceptible to complete water trapping.

  15. Jet and disk luminosities in tidal disruption events

    E-Print Network [OSTI]

    Piran, Tsvi; Tchekhovskoy, Alexander

    2015-01-01

    Tidal disruption events (TDE) in which a star is devoured by a massive black hole at a galac- tic center pose a challenge to our understanding of accretion processes. Within a month the accretion rate reaches super-Eddington levels. It then drops gradually over a time scale of a year to sub-Eddington regimes. The initially geometrically thick disk becomes a thin one and eventually an ADAF at very low accretion rates. As such, TDEs explore the whole range of accretion rates and configurations. A challenging question is what the corresponding light curves of these events are. We explore numerically the disk luminosity and the conditions within the inner region of the disk using a fully general relativistic slim disk model. Those conditions determine the magnitude of the magnetic field that engulfs the black hole and this, in turn, determines the Blandford-Znajek jet power. We estimate this power in two different ways and show that they are self-consistent. We find, as expected earlier from analytic argu- ments ...

  16. SKA as a powerful hunter of jetted Tidal Disruption Events

    E-Print Network [OSTI]

    Donnarumma, I; Fender, R; Komossa, S; Paragi, Z; Van Velzen, S; Prandoni, I

    2015-01-01

    Observational consequences of the tidal disruption of stars by supermassive black holes (SMBHs) can enable us to discover quiescent SMBHs and constrain their mass function. Moreover, observing jetted TDEs (from previously non-active galaxies) provides us with a new means of studying the early phases of jet formation and evolution in an otherwise "pristine" environment. Although several (tens) TDEs have been discovered since 1999, only two jetted TDEs have been recently discovered in hard X-rays, and only one, Swift J1644+57, has a precise localization which further supports the TDE interpretation. These events alone are not sufficient to address those science issues, which require a substantial increase of the current sample. Despite the way they were discovered, the highest discovery potential for {\\em jetted} TDEs is not held by current and up-coming X-ray instruments, which will yield only a few to a few tens events per year. In fact, the best strategy is to use the Square Kilometer Array to detect TDEs an...

  17. "Circularization" vs. Accretion -- What Powers Tidal Disruption Events?

    E-Print Network [OSTI]

    Tsvi Piran; Gilad Svirski; Julian Krolik; Roseanne M. Cheng; Hotaka Shiokawa

    2015-04-07

    A tidal disruption event (TDE) takes place when a star passes near enough to a massive black hole to be disrupted. About half the star's matter is given elliptical trajectories with large apocenter distances, the other half is unbound. To "circularize", i.e., to form an accretion flow, the bound matter must lose a significant amount of energy, with the actual amount depending on the characteristic scale of the flow measured in units of the black hole's gravitational radius ($\\sim 10^{51} (R/1000R_g)^{-1}$~erg). Recent numerical simulations \\citep{Shiokawa+2015} have revealed that the circularization scale is close to the scale of the most-bound initial orbits, $\\sim 10^3 M_{BH,6.5}^{-2/3} R_g \\sim 10^{15} M_{BH,6.5}^{1/3}$~cm from the black hole, and the corresponding circularization energy dissipation rate is $\\sim 10^{44} M_{BH,6.5}^{-1/6}$~erg/s. We suggest that the energy liberated during circularization, rather then energy liberated by accretion onto the black hole, powers the observed optical TDE candidates. The observed rise times, luminosities, temperatures, emission radii, and line widths seen in these TDEs \\citep[e.g.][]{Arcavi+2014} are all more readily explained in terms of heating associated with circularization than in terms of accretion.

  18. Tidal Accelerometry: Exploring the Cosmos Via Gravitational Correlations

    E-Print Network [OSTI]

    Datta, Timir; Wescott, Mike; Jeong, Yeuncheol; Morawiec, Pawel; Gambrell, James; Overcash, Dan; Zhang, Huaizhou; Voulgaris, George

    2010-01-01

    Newtonian gravitation is non-radiative but is extremely pervasive and penetrates equally into every media because it cannot be shielded. The extra terrestrial fgravity is responsible for earth's trajectory. However its correlation or geodesic deviation is manifested as semi-diurnal and diurnal tides. Tidal signals, A(t) are temporal modulations in the field differential which can be observed in a wide variety of natural and laboratory situations. A(t) is a quasi-static, low frequency signal which arises from the relative changes in positions of the detector and source and is not part of the electromagnetic spectrum. Isaac Newton was the first to recognize the importance of tides in astrometry and attempetd to estimate lunar mass from ocean tides. By a case study we show, how the systematics of the gravitational correlation can be used for calibration and de-trending which can significantly increase the confidence level of high precision experiments. A(t) can also be used to determine the distribution of celes...

  19. Scaling laws to understand tidal dissipation in fluid planetary regions and stars I - Rotation, stratification and thermal diffusivity

    E-Print Network [OSTI]

    Auclair-Desrotour, P; Poncin-Lafitte, C Le

    2015-01-01

    Tidal dissipation in planets and stars is one of the key physical mechanisms driving the evolution of star-planet and planet-moon systems. Several signatures of its action are observed in planetary systems thanks to their orbital architecture and the rotational state of their components. Tidal dissipation inside the fluid layers of celestial bodies are intrinsically linked to the dynamics and the physical properties of the latter. This complex dependence must be characterized. We compute the tidal kinetic energy dissipated by viscous friction and thermal diffusion in a rotating local fluid Cartesian section of a star/planet/moon submitted to a periodic tidal forcing. The properties of tidal gravito-inertial waves excited by the perturbation are derived analytically as explicit functions of the tidal frequency and local fluid parameters (i.e. the rotation, the buoyancy frequency characterizing the entropy stratification, viscous and thermal diffusivities) for periodic normal modes. The sensitivity of the resul...

  20. Subtropical catastrophe: Significant loss of low-mode tidal energy at J. A. MacKinnon and K. B. Winters

    E-Print Network [OSTI]

    MacKinnon, Jennifer

    Subtropical catastrophe: Significant loss of low-mode tidal energy at 28.9°° J. A. MacKinnon and K with a northward baroclinic tidal flux of approximately 1.7 kW/m. After an initial spinup period, energy is quickly of low-mode tidal energy at 28.9°, Geophys. Res. Lett., 32, L15605, doi:10.1029/ 2005GL023376. 1

  1. Two-and three-dimensional double-sandbar system behaviour under intense wave forcing and a mesomacro tidal range

    E-Print Network [OSTI]

    ­macro tidal range R. Almar a,b,Ã, B. Castelle a,b , B.G. Ruessink c , N. Se´ne´chal a,b , P. Bonneton a,b , V­macro tidal environment Storm impact Nearshore Video imaging Short-term morphodynamics Truc Vert Beach a b s t r a c t Five weeks of hourly, 10-min time-exposure video images were used to analyze the meso­macro-tidal

  2. Modeling of In-stream Tidal Energy Development and its Potential Effects in Tacoma Narrows, Washington, USA

    SciTech Connect (OSTI)

    Yang, Zhaoqing; Wang, Taiping; Copping, Andrea E.; Geerlofs, Simon H.

    2014-10-01

    Understanding and providing proactive information on the potential for tidal energy projects to cause changes to the physical system and to key water quality constituents in tidal waters is a necessary and cost-effective means to avoid costly regulatory involvement and late stage surprises in the permitting process. This paper presents a modeling study for evaluating the tidal energy extraction and its potential impacts on the marine environment in a real world site - Tacoma Narrows of Puget Sound, Washington State, USA. An unstructured-grid coastal ocean model, fitted with a module that simulates tidal energy devices, was applied to simulate the tidal energy extracted by different turbine array configurations and the potential effects of the extraction at local and system-wide scales in Tacoma Narrows and South Puget Sound. Model results demonstrated the advantage of an unstructured-grid model for simulating the far-field effects of tidal energy extraction in a large model domain, as well as assessing the near-field effect using a fine grid resolution near the tidal turbines. The outcome shows that a realistic near-term deployment scenario extracts a very small fraction of the total tidal energy in the system and that system wide environmental effects are not likely; however, near-field effects on the flow field and bed shear stress in the area of tidal turbine farm are more likely. Model results also indicate that from a practical standpoint, hydrodynamic or water quality effects are not likely to be the limiting factor for development of large commercial-scale tidal farms. Results indicate that very high numbers of turbines are required to significantly alter the tidal system; limitations on marine space or other environmental concerns are likely to be reached before reaching these deployment levels. These findings show that important information obtained from numerical modeling can be used to inform regulatory and policy processes for tidal energy development.

  3. Dispersion mechanisms of a tidal river junction in the Sacramento–San Joaquin Delta, California

    SciTech Connect (OSTI)

    Gleichauf, Karla T.; Wolfram, Philip J.; Monsen, Nancy E.; Fringer, Oliver B.; Monismith, Stephen G.

    2014-12-17

    In branching channel networks, such as in the Sacramento–San Joaquin River Delta, junction flow dynamics contribute to dispersion of ecologically important entities such as fish, pollutants, nutrients, salt, sediment, and phytoplankton. Flow transport through a junction largely arises from velocity phasing in the form of divergent flow between junction channels for a portion of the tidal cycle. Field observations in the Georgiana Slough junction, which is composed of the North and South Mokelumne rivers, Georgiana Slough, and the Mokelumne River, show that flow phasing differences between these rivers arise from operational, riverine, and tidal forcing. A combination of Acoustic Doppler Current Profile (ADCP) boat transecting and moored ADCPs over a spring–neap tidal cycle (May to June 2012) monitored the variability of spatial and temporal velocity, respectively. Two complementary drifter studies enabled assessment of local transport through the junction to identify small-scale intrajunction dynamics. We supplemented field results with numerical simulations using the SUNTANS model to demonstrate the importance of phasing offsets for junction transport and dispersion. Different phasing of inflows to the junction resulted in scalar patchiness that is characteristic of MacVean and Stacey’s (2011) advective tidal trapping. Furthermore, we observed small-scale junction flow features including a recirculation zone and shear layer, which play an important role in intra-junction mixing over time scales shorter than the tidal cycle (i.e., super-tidal time scales). Thus, the study period spanned open- and closed-gate operations at the Delta Cross Channel. Synthesis of field observations and modeling efforts suggest that management operations related to the Delta Cross Channel can strongly affect transport in the Delta by modifying the relative contributions of tidal and riverine flows, thereby changing the junction flow phasing.

  4. Dispersion mechanisms of a tidal river junction in the Sacramento–San Joaquin Delta, California

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gleichauf, Karla T.; Wolfram, Philip J.; Monsen, Nancy E.; Fringer, Oliver B.; Monismith, Stephen G.

    2014-12-17

    In branching channel networks, such as in the Sacramento–San Joaquin River Delta, junction flow dynamics contribute to dispersion of ecologically important entities such as fish, pollutants, nutrients, salt, sediment, and phytoplankton. Flow transport through a junction largely arises from velocity phasing in the form of divergent flow between junction channels for a portion of the tidal cycle. Field observations in the Georgiana Slough junction, which is composed of the North and South Mokelumne rivers, Georgiana Slough, and the Mokelumne River, show that flow phasing differences between these rivers arise from operational, riverine, and tidal forcing. A combination of Acoustic Dopplermore »Current Profile (ADCP) boat transecting and moored ADCPs over a spring–neap tidal cycle (May to June 2012) monitored the variability of spatial and temporal velocity, respectively. Two complementary drifter studies enabled assessment of local transport through the junction to identify small-scale intrajunction dynamics. We supplemented field results with numerical simulations using the SUNTANS model to demonstrate the importance of phasing offsets for junction transport and dispersion. Different phasing of inflows to the junction resulted in scalar patchiness that is characteristic of MacVean and Stacey’s (2011) advective tidal trapping. Furthermore, we observed small-scale junction flow features including a recirculation zone and shear layer, which play an important role in intra-junction mixing over time scales shorter than the tidal cycle (i.e., super-tidal time scales). Thus, the study period spanned open- and closed-gate operations at the Delta Cross Channel. Synthesis of field observations and modeling efforts suggest that management operations related to the Delta Cross Channel can strongly affect transport in the Delta by modifying the relative contributions of tidal and riverine flows, thereby changing the junction flow phasing.« less

  5. Optimal Control of a Grid-Connected Hybrid Electrical Energy Storage System for Homes

    E-Print Network [OSTI]

    Pedram, Massoud

    with the introduction of dynamic electricity energy pricing models since electricity consumers can use their PV function and the energy storage capacity limitation, the control algorithm for a residential EES system period under a general electricity energy price function. The proposed algorithm is based on dynamic

  6. Maximizing Return on Investment of a Grid-Connected Hybrid Electrical Energy Storage System

    E-Print Network [OSTI]

    Pedram, Massoud

    -of-day pricing policy [3] with much higher energy price during peak hours for residential users, incentivizing energy when the electricity price is low and supply energy for use when the electricity price is high [6/or supercapacitors. Incorporation of EES system effectively shifts the residential peak hour energy demand from

  7. Aalborg Universitet Selective compensation of voltage harmonics in grid-connected microgrids

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    , Aalborg east DK-9220, Denmark c Department of electrical engineering, National Sun Yat-sen University of science and technology, Tehran 16846-13114, Iran b Institute of energy technology, Aalborg University

  8. Optimal Design of Grid-Connected PEV Charging Systems With Integrated Distributed Resources

    E-Print Network [OSTI]

    Perreault, David J.

    The penetration of plug-in electric vehicles and renewable distributed generation is expected to increase over the next few decades. Large scale unregulated deployment of either technology can have a detrimental impact on ...

  9. Homeowners Guide to Financing a Grid-Connected Solar Electric System

    SciTech Connect (OSTI)

    Solar Energy Technologies Program

    2010-10-11

    This guide provides an overview of the financing options that may be available to homeowners who are considering installing a solar electric system on their house.

  10. Homeowners Guide to Financing a Grid-Connected Solar Electric System (Brochure)

    SciTech Connect (OSTI)

    Not Available

    2010-10-01

    This guide provides an overview of the financing options that may be available to homeowners who are considering installing a solar electric system on their house.

  11. First U.S. Grid-Connected Offshore Wind Turbine Installed Off...

    Broader source: Energy.gov (indexed) [DOE]

    Composites Center partnered with Maine Maritime Academy and Cianbro to launch a deepwater offshore floating wind turbine near Bangor. When the turbine was turned on and electricity...

  12. Market Transformation Pathways for Grid-Connected Rooftop Solar PV in Minnesota

    SciTech Connect (OSTI)

    Abbey, Ross; Ross, Brian

    2013-06-03

    This report presents the market and policy findings of the Minnesota Solar Challenge program. The report draws on information collected from state agencies, local government units, solar industry participants, rooftop photovoltaic (PV) adopters (sometimes called customer-generators), state and national experts, the Commerce distributed generation stakeholder process, and the numerous reports and data sets referenced herein.

  13. Estimating the maximum potential revenue for grid connected electricity storage : arbitrage and regulation.

    SciTech Connect (OSTI)

    Byrne, Raymond Harry; Silva Monroy, Cesar Augusto.

    2012-12-01

    The valuation of an electricity storage device is based on the expected future cash ow generated by the device. Two potential sources of income for an electricity storage system are energy arbitrage and participation in the frequency regulation market. Energy arbitrage refers to purchasing (stor- ing) energy when electricity prices are low, and selling (discharging) energy when electricity prices are high. Frequency regulation is an ancillary service geared towards maintaining system frequency, and is typically procured by the independent system operator in some type of market. This paper outlines the calculations required to estimate the maximum potential revenue from participating in these two activities. First, a mathematical model is presented for the state of charge as a function of the storage device parameters and the quantities of electricity purchased/sold as well as the quantities o ered into the regulation market. Using this mathematical model, we present a linear programming optimization approach to calculating the maximum potential revenue from an elec- tricity storage device. The calculation of the maximum potential revenue is critical in developing an upper bound on the value of storage, as a benchmark for evaluating potential trading strate- gies, and a tool for capital nance risk assessment. Then, we use historical California Independent System Operator (CAISO) data from 2010-2011 to evaluate the maximum potential revenue from the Tehachapi wind energy storage project, an American Recovery and Reinvestment Act of 2009 (ARRA) energy storage demonstration project. We investigate the maximum potential revenue from two di erent scenarios: arbitrage only and arbitrage combined with the regulation market. Our analysis shows that participation in the regulation market produces four times the revenue compared to arbitrage in the CAISO market using 2010 and 2011 data. Then we evaluate several trading strategies to illustrate how they compare to the maximum potential revenue benchmark. We conclude with a sensitivity analysis with respect to key parameters.

  14. Hourly Simulation of Grid-Connected PV Systems Using Realistic Building Loads (Preprint)

    SciTech Connect (OSTI)

    Balcomb, J.D.; Hayter, S.J.; Weaver, N.L.

    2001-02-27

    This is one of two companion papers that describe the ENERGY-10 PV design tool computer simulation program. The other paper is titled ''ENERGY-10 Photovoltaics: A New Capability.'' Whereas this paper focuses on the PV aspects of the program, the companion paper focuses on the implementation method. The case study in this paper is a commercial building application, whereas the case study in the companion paper is a residential application with an entirely different building load characteristic. Together they provide a balanced view.

  15. Aalborg Universitet Modular Multi-level converter based HVDC System for Grid Connection of Offshore

    E-Print Network [OSTI]

    Chaudhary, Sanjay

    energy is an important renewable and green source of energy. The total installed worldwide capacity is to install large offshore wind power plants (WPP) because they offer higher energy yield due to a superior

  16. Battery Management for Grid-Connected PV Systems with a Battery

    E-Print Network [OSTI]

    Pedram, Massoud

    -connected systems, Photovoltaic power, Electricity bill 1. INTRODUCTION The number and capacity of photovoltaic (PV}@usc.edu ABSTRACT Photovoltaic (PV) power generation systems are one of the most promising renewable power sources into account the limited battery capacity, power converter efficiency, battery's internal re- sistance and rate

  17. Performance of a grid connected residential photovoltaic system with energy storage

    SciTech Connect (OSTI)

    Palomino, G.E. [SRP, Phoenix, AZ (United States); Wiles, J. [Southwest Technology Development Institute, Las Cruces, NM (United States); Stevens, J. [Sandia National Labs., Albuquerque, NM (United States); Goodman, F. [EPRI, Palo Alto, CA (United States)

    1997-11-01

    In 1995, Salt River Project (SRP), a public power utility located in Phoenix, Arizona, collaborated with the Electric Power Research Institute (EPRI) and Sandia National Laboratories (Sandia) to initiate a photovoltaic (PV) power system with battery energy storage to match PV output with residential customer peak energy demand periods. The PV power system, a 2.4kW PV array with 25.2kWh of energy storage, was designed and installed by Southwest Technology Development Institute (SWTDI) at an SRP-owned facility, known as the Chandler Research House during August 1995. This paper presents an overview of the system design, operation and performance. 3 refs., 2 figs., 2 tabs.

  18. Aalborg Universitet Harmonic Stability Assessment for Multi-Paralleled, Grid-Connected Inverters

    E-Print Network [OSTI]

    Bak, Claus Leth

    In these days, many alternative energy resources have been developed to meet the expected future electric energy Department of Energy Technology Aalborg University Aalborg, Denmark cyo@et.aau.dk Abstract--This paper consumption and they are now widely commercialized [1]. However, as new energy resources are employed

  19. Grid-Connected Renewable Energy Generation Toolkit-Biomass | Open Energy

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View New PagesSustainableGlynn County,Solar Jump to:Resources JumpStrategy |Financing

  20. Grid-Connected Renewable Energy Generation Toolkit-Geothermal | Open Energy

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View New PagesSustainableGlynn County,Solar Jump to:Resources JumpStrategy

  1. MHK Projects/Evopod E35 35kW grid connected demonstrator | Open Energy

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas:Montezuma,Information MHKMHK5 < MHK Projects JumpDevelopment of

  2. Chile-GTZ Public Properties for Grid-connected Renewable Energy Projects |

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LISTStar Energy LLCLtd Jump to:Changing WorldCalifornia: Energy Resources

  3. Mongolia-GTZ Energy Efficiency within the Grid-Connected Energy Supply |

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop Inc Jump to: navigation,Mereg GmbH JumpLLCMohave Electric(EC-LEDS)Development

  4. Grid-Connected Renewable Energy Generation Toolkit-Solar | Open Energy

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LISTStar2-0057-EA Jump to:ofEniaElectricHydroLegal Documents Jump to:Information

  5. Grid-Connected Renewable Energy Generation Toolkit-Wind | Open Energy

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LISTStar2-0057-EA Jump to:ofEniaElectricHydroLegal Documents Jump

  6. First U.S. Grid-Connected Offshore Wind Turbine Installed Off the Coast of

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergyTher i nA Guide to Tapping into Funding for EnergyOctober 8,<Updates |wasMaine |

  7. MHK Projects/Evopod E1 1 10 scale grid connected demonstrator | Open Energy

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource HistoryScenarios Towards 2050 JumpCoos Bay OPT Wave ParkDouglas

  8. DOE Publishes Notice of Public Meeting for Smart Grid-connected Buildings |

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergyTher i n c i pStateDOE FederalThe Department ofFederalLEDWhile previousDepartment of

  9. A $5 Million Boost for Midsize Wind Turbines and Grid Connectivity |

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergyTher i n c i p a l De p u t y A s s iof1 of 8 2

  10. Maine Project Launches First Grid-Connected Offshore Wind Turbine in the

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCED MANUFACTURING OFFICE INDUSTRIALU.S.LeadershipLumiledsof EnergyMagnetocaloricMagnoliaU.S. |

  11. Integration Technology for PHEV-Grid-Connectivity, with Support for SAE

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCED MANUFACTURING OFFICE INDUSTRIAL TECHNICAL8-02Department of EnergySTD-1189-2008 March

  12. Nevada Deploys First U.S. Commercial, Grid-Connected Enhanced Geothermal

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirley Ann JacksonDepartment ofOffice|in the subsurface is better6, 2015 2:00PM toSchuldenfrei

  13. General Relativistic Hydrodynamic Simulation of Accretion Flow from a Stellar Tidal Disruption

    E-Print Network [OSTI]

    Shiokawa, Hotaka; Cheng, Roseanne M; Piran, Tsvi; Noble, Scott C

    2015-01-01

    We study how the matter dispersed when a supermassive black hole tidally disrupts a star joins an accretion flow. Combining a relativistic hydrodynamic simulation of the stellar disruption with a relativistic hydrodynamics simulation of the tidal debris motion, we track such a system until ~80% of the stellar mass bound to the black hole has settled into an accretion flow. Shocks near the stellar pericenter and also near the apocenter of the most tightly-bound debris dissipate orbital energy, but only enough to make the characteristic radius comparable to the semi-major axis of the most-bound material, not the tidal radius as previously thought. The outer shocks are caused by post-Newtonian effects, both on the stellar orbit during its disruption and on the tidal forces. Accumulation of mass into the accretion flow is non-monotonic and slow, requiring ~3--10x the orbital period of the most tightly-bound tidal streams, while the inflow time for most of the mass may be comparable to or longer than the mass accu...

  14. Mapping the Potential of U.S. Ocean Energy | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    undertaken to date to accurately define the magnitude and location of U.S. and global wave, tidal, ocean thermal, and continental U.S. river hydrokinetic resources. With more...

  15. Microsoft Word - RM 1-3 Final Report Nov 2011 final.docx

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    entangled in mooring lines. As the size of wave, 2.7 tidal, or riverine hydrokinetic farms grow, regulations are likely to require that studies include those focused further...

  16. Sandia Energy - EC Publications

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Field Measurements at River and Tidal Current Sites for Hydrokinetic Energy Development: Best Practices ManualTara Camacho-Lopez2015-04-06T22:15:34+00:00 Placeholder Download...

  17. Sandia Energy - EC Publications

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energy (DoE) is assessing and mapping the potential off-shore ocean current hydrokinetic energy resources along the U.S. coastline, excluding tidal currents, to facilitate market...

  18. CX-006240: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Acoustic Effects of Hydrokinetic Tidal TurbinesCX(s) Applied: B3.1, B3.3Date: 07/15/2011Location(s): WashingtonOffice(s): Energy Efficiency and Renewable Energy, Golden Field Office

  19. Tidal dissipation in a homogeneous spherical body. II. Three examples: Mercury, Io, and Kepler-10 b

    SciTech Connect (OSTI)

    Makarov, Valeri V.; Efroimsky, Michael E-mail: michael.efroimsky@usno.navy.mil

    2014-11-01

    In Efroimsky and Makarov (Paper I), we derived from the first principles a formula for the tidal heating rate in a homogeneous sphere, compared it with the previously used formulae, and noted the differences. Now we present case studies: Mercury, Kepler-10 b, and a triaxial Io. A sharp frequency dependence of k {sub 2}/Q near spin-orbit resonances yields a sharp dependence of k {sub 2}/Q (and, therefore, of tidal heating) upon the spin rate. Thereby physical libration plays a major role in tidal heating of synchronously rotating planets. The magnitude of libration in the spin rate being defined by the planet's triaxiality, the latter becomes a factor determining the dissipation rate. Other parameters equal, a strongly triaxial synchronized body generates more heat than a similar body of a more symmetrical shape. After an initially triaxial object melts and loses its triaxiality, dissipation becomes less intensive; the body can solidify, with the tidal bulge becoming a new figure with triaxiality lower than the original. We derive approximate expressions for the dissipation rate in a Maxwell planet with the Maxwell time longer than the inverse tidal frequency. The expressions derived pertain to the 1:1 and 3:2 resonances and a nonresonant case; so they are applicable to most close-in super-Earths detected. In these planets, the heating outside synchronism is weakly dependent on the eccentricity and obliquity, provided both these parameters's values are moderate. According to our calculation, Kepler-10 b could hardly survive the intensive tidal heating without being synchronized, circularized, and reshaped through a complete or partial melt-down.

  20. Macroscopic traversable wormholes with zero tidal forces inspired by noncommutative geometry

    E-Print Network [OSTI]

    Peter K. F. Kuhfittig

    2015-01-08

    This paper addresses the following issues: (1) the possible existence of macroscopic traversable wormholes, given a noncommutative-geometry background, and (2) the possibility of allowing zero tidal forces, given a known density. It is shown that whenever the energy density describes a classical wormhole, the resulting solution is incompatible with quantum field theory. If the energy density originates from noncommutative geometry, then zero tidal forces are allowed. Also attributable to the noncommutative geometry is the violation of the null energy condition. The wormhole geometry satisfies the usual requirements, including asymptotic flatness.

  1. Detection of Gravitational Wave Emission by Supermassive Black Hole Binaries Through Tidal Disruption Flares

    E-Print Network [OSTI]

    Hayasaki, Kimitake

    2015-01-01

    Galaxy mergers produce binaries of supermassive black holes, which emit gravitational waves prior to their coalescence. We perform three-dimensional hydrodynamic simulations to study the tidal disruption of stars by such a binary in the final centuries of its life. We find that the gas stream of the stellar debris moves chaotically in the binary potential and forms accretion disks around both black holes. The accretion light curve is modulated over the binary orbital period owing to relativistic beaming. This periodic signal allows to detect the decay of the binary orbit due to gravitational wave emission by observing two tidal disruption events that are separated by more than a decade.

  2. MHK Projects/Homeowner Tidal Power Elec Gen | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource HistoryScenarios Towards 2050 JumpCoos Bay OPTHalf Moon Cove TidalTidal

  3. Aggradation of gravels in tidally influenced fluvial systems: upper Albian (Lower Cretaceous) on the cratonic margin of the North

    E-Print Network [OSTI]

    González, Luis A.

    Aggradation of gravels in tidally influenced fluvial systems: upper Albian (Lower Cretaceous for the required water supply flux. Regardless of temporal scale, gravels were transported during `high-energy at the mouths of the river system, and tidal effects were transmitted at least 200 km inland from

  4. Distribution of Energy Spectra, Reynolds Stresses, Turbulence Production, and Dissipation in a Tidally Driven Bottom Boundary Layer

    E-Print Network [OSTI]

    Distribution of Energy Spectra, Reynolds Stresses, Turbulence Production, and Dissipation in a Tidally Driven Bottom Boundary Layer L. LUZNIK,* R. GURKA,*, W. A. M. NIMMO SMITH,# W. ZHU,* J. KATZ) site] are examined, covering the accelerating and decelerating phases of a single tidal cycle

  5. will appear in Journal of Geophysical Research, 2001. Observations of turbulence in a tidal beam and across a coastal ridge

    E-Print Network [OSTI]

    Lien, Ren-Chieh

    1 will appear in Journal of Geophysical Research, 2001. Observations of turbulence in a tidal beam the turbulence kinetic energy dissipation rate exceeded 10-6 W kg-1 , and the diapycnal eddy diffusivity K varied by a factor of 100 with a semidiurnal tidal periodicity; the isopycnal displacement confirmed

  6. Factors Determining the Location of the Chlorophyll Maximum and the Fate of Algal Production within the Tidal

    E-Print Network [OSTI]

    Bukaveckas, Paul A.

    that cause the formation of a chlorophyll maximum within the tidal freshwater James River. Phyto- plankton in their dominant mode of hydrodynamics, tidal freshwaters share a number of features in common with rivers of the saline estuary. Their hydrodynamics are dominated by bi- directional flow but are subject to considerable

  7. Surface M2 tidal currents along the North Carolina shelf observed with a high-frequency radar

    E-Print Network [OSTI]

    Miami, University of

    Surface M2 tidal currents along the North Carolina shelf observed with a high-frequency radar measured by a high-frequency (HF) radar. The Ocean Surface Current Radar (OSCR) was deployed at the U. M., and L. K. Shay, Surface M2 tidal currents along the North Carolina shelf observed with a high-frequency

  8. Feasibility of Tidal and Ocean Current Energy in False Pass, Aleutian Islands, Alaska FINAL REPORT

    SciTech Connect (OSTI)

    Wright, Bruce Albert

    2014-05-07

    The Aleutian Pribilof Islands Association was awarded a U.S. Department of Energy Tribal Energy Program grant (DE-EE0005624) for the Feasibility of Tidal and Ocean Current Energy in False Pass, Aleutian Islands, Alaska (Project). The goal of the Project was to perform a feasibility study to determine if a tidal energy project would be a viable means to generate electricity and heat to meet long-term fossil fuel use reduction goals, specifically to produce at least 30% of the electrical and heating needs of the tribally-owned buildings in False Pass. The Project Team included the Aleut Region organizations comprised of the Aleutian Pribilof Island Association (APIA), and Aleutian Pribilof Island Community Development Association (APICDA); the University of Alaska Anchorage, ORPC Alaska a wholly-owned subsidiary of Ocean Renewable Power Company (ORPC), City of False Pass, Benthic GeoScience, and the National Renewable Energy Laboratory (NREL). The following Project objectives were completed: collected existing bathymetric, tidal, and ocean current data to develop a basic model of current circulation at False Pass, measured current velocities at two sites for a full lunar cycle to establish the viability of the current resource, collected data on transmission infrastructure, electrical loads, and electrical generation at False Pass, performed economic analysis based on current costs of energy and amount of energy anticipated from and costs associated with the tidal energy project conceptual design and scoped environmental issues. Utilizing circulation modeling, the Project Team identified two target sites with strong potential for robust tidal energy resources in Isanotski Strait and another nearer the City of False Pass. In addition, the Project Team completed a survey of the electrical infrastructure, which identified likely sites of interconnection and clarified required transmission distances from the tidal energy resources. Based on resource and electrical data, the Project Team developed a conceptual tidal energy project design utilizing ORPC’s TidGen® Power System. While the Project Team has not committed to ORPC technology for future development of a False Pass project, this conceptual design was critical to informing the Project’s economic analysis. The results showed that power from a tidal energy project could be provided to the City of False at a rate at or below the cost of diesel generated electricity and sold to commercial customers at rates competitive with current market rates, providing a stable, flat priced, environmentally sound alternative to the diesel generation currently utilized for energy in the community. The Project Team concluded that with additional grants and private investment a tidal energy project at False Pass is well-positioned to be the first tidal energy project to be developed in Alaska, and the first tidal energy project to be interconnected to an isolated micro grid in the world. A viable project will be a model for similar projects in coastal Alaska.

  9. The Cascade of Tidal Energy from Low to High Modes on a Continental Slope SAMUEL M. KELLY* AND JONATHAN D. NASH

    E-Print Network [OSTI]

    The Cascade of Tidal Energy from Low to High Modes on a Continental Slope SAMUEL M. KELLY 25 March 2012) ABSTRACT The linear transfer of tidal energy from large to small scales is quantified. Observed transfer of tidal energy into high-mode internal tides is quantitatively consistent with observed

  10. JOURNAL OF GEOPHYSICAL RESEARCH, VOL. ???, XXXX, DOI:10.1029/, Dissipation at tidal and seismic frequencies in a melt-free,

    E-Print Network [OSTI]

    Nimmo, Francis

    be readily detectable with future seismological observations. 1. Introduction The rate at which tidal energyJOURNAL OF GEOPHYSICAL RESEARCH, VOL. ???, XXXX, DOI:10.1029/, Dissipation at tidal and seismic of Phobos provides a constraint on the tidal dissipation factor, Q, within Mars. We model viscoelastic

  11. A simple parameterization of turbulent tidal mixing near supercritical topography JODY M. KLYMAK1, SONYA LEGG2, AND ROBERT PINKEL3

    E-Print Network [OSTI]

    Klymak, Jody M.

    MAY 2010 1 A simple parameterization of turbulent tidal mixing near supercritical topography JODY M Jolla CA, 98105, USA (Manuscript received , in final form ) ABSTRACT A simple parameterization for tidal wave modes that have non-rotating phase speeds slower than the tidal advection speed are assumed

  12. PHYSIOLOGICAL PERFORMANCE OF INTERTIDAL CORALLINE ALGAE DURING A SIMULATED TIDAL CYCLE1

    E-Print Network [OSTI]

    Martone, Patrick T.

    PHYSIOLOGICAL PERFORMANCE OF INTERTIDAL CORALLINE ALGAE DURING A SIMULATED TIDAL CYCLE1 Rebecca J, Lobban and Harrison 1997, Helmuth and Hofmann 2001). During high tide, intertidal algae are underwater algae may be emerged and exposed to increased light stress, elevated air tem- peratures, and increased

  13. Modeling tidal flow in the Great Bay Estuary, New Hampshire, using a depth averaged

    E-Print Network [OSTI]

    Modeling tidal flow in the Great Bay Estuary, New Hampshire, using a depth averaged flooding, University of New Hampshire, USA. 2 Numerical Methods Lab., Dartmouth College, USA. 3 Ocean Process Analysis Lab., University of New Hampshire, USA. Abstract Current, sea level and bed load transport

  14. Tidal heating of Earth-like exoplanets around M stars: Thermal, magnetic, and orbital evolutions

    E-Print Network [OSTI]

    Driscoll, Peter

    2015-01-01

    The internal thermal and magnetic evolution of rocky exoplanets is critical to their habitability. We focus on the thermal-orbital evolution of Earth-mass planets around low mass M stars whose radiative habitable zone overlaps with the "tidal zone". We develop a thermal-orbital evolution model calibrated to Earth that couples tidal dissipation, with a temperature-dependent Maxwell rheology, to orbital circularization and migration. We illustrate thermal-orbital steady states where surface heat flow is balanced by tidal dissipation and cooling can be stalled for billions of years until circularization occurs. Orbital energy dissipated as tidal heat in the interior drives both inward migration and circularization, with a circularization time that is inversely proportional to the dissipation rate. We identify a peak in the internal dissipation rate as the mantle passes through a visco-elastic state at mantle temperatures near 1800 K. Planets orbiting a 0.1 solar-mass star within $0.07$ AU circularize before 10 G...

  15. EVALUATION OF TIDAL INLETS CHANNEL MIGRATION AND MANAGEMENT PRACTICES IN SOUTHWEST FLORIDA

    E-Print Network [OSTI]

    US Army Corps of Engineers

    484 EVALUATION OF TIDAL INLETS CHANNEL MIGRATION AND MANAGEMENT PRACTICES IN SOUTHWEST FLORIDA are analyzed to understand common factors that contribute to channel migration for inlets with/without jetties depth sufficient for reliable navigation in critical shoaling areas. In addition, ebb shoals have been

  16. Radar interferometry for measuring tidal strains across cracks on David Sandwell,1

    E-Print Network [OSTI]

    Sandwell, David T.

    Radar interferometry for measuring tidal strains across cracks on Europa David Sandwell,1 Paul and the plate has been relatively thin ($2 km) [Carr et al., 1998]. However, the present-day average shell relationships and a variety of morphologic characteristics [Carr et al., 1998; Greenberg et al., 1998]. Simple

  17. TIDAL ENERGY SITE RESOURCE ASSESSMENT: TECHNICAL SPECIFICATIONS, BEST PRACTICES AND CASE STUDIES

    E-Print Network [OSTI]

    Siefert, Chris

    , Wind and Water Power Technologies, Environmental Sciences Division, Oak Ridge National Laboratory, Oak fashion, we can develop tidal energy site classes that map to standard TEC designs, similar to the wind over a representative period of record, to design the structural loading and power capacity of the TEC

  18. Tidal constituent database. West Coast of the United States and Eastern North pacific ocean. Technical note

    SciTech Connect (OSTI)

    NONE

    1995-01-01

    This technical note describes a database of tidal elevation boundary condition information generated in support of the `Long-Term Fate of Dredged Material Disposed in Open Water` research of the Dredging Research Program (DRP), being conducted at the U.S. Army Engineer Waterways Experiment Station. The database, described in detail by Hench and others (1994), allows the user to manually generate time series of tidal elevations or to use a program to access the full database to generate time series of both tidal elevations and currents for any location along the West Coast of the United States and Eastern North Pacific Ocean, extending from Seal Cape on Unimak Island, Alaska, in the North to Punta Parada, Peru, in the South. The land boundary includes the Pacific shorelines of Alaska, Canada, mainland United States, Mexico, Guatemala, El Salvador, Nicaragua, Costa Rica, Panama, Columbia, and Northern Peru. Although the capability to generate these time series was developed to provide input to the Long-Term Fate and Stability Model (LTFATE), the generated time series can be used for any application requiring tidal forcing data.

  19. The record of sea level rise by tidal sand bodies of the English Channel

    SciTech Connect (OSTI)

    Berne, S; Lericolais, G. (Ifremer, Plouzane, (France)); Lafont, F. (Universite d'Orsay (France))

    1990-05-01

    Improvements of very high resolution seismic reflection provide new information about internal structures of modern sand bodies. This allows us to reconstruct their recent history, which is related to the Holocene sea level rise. A major distinction is found between inner shelf sand bodies, dominated by autocyclic processes, and outer shelf sand bodies, where allocyclic processes are invoked to explain the apparent contradiction between internal structures and present-day dynamics. On the inner shelf, evidence of the migration of tidal dunes (sand waves) has been obtained by repeated surveys using accurate positioning systems. Major bounding surfaces are thought to result from the action of tidal current and/or from episodic storms. A rough estimation of the age of these sand bodies can be proposed. On the outer shelf, some dunes of the English Channel exhibit cross-beds indicative of a past net bed-load transport at the opposite of present days dynamics, inherited from different tidal conditions when sea level was between 20 and 40 m lower. Some large tidal sand banks (e.g., the Sark Bank near the Channel Islands) display a more complicated pattern. The upper part of the sand bank is the result of the migration of very large dunes climbing at positive angles, whereas the lower part shows major erosional surfaces, attributed to the action of storms during lower sea levels.

  20. FLORAL AND FAUNAL DIFFERENCES BETWEEN FRAGMENTED AND UNFRAGMENTED BAHAMIAN TIDAL CREEKS

    E-Print Network [OSTI]

    Langerhans, Brian

    Valentine-Rose1,7 , Julia A. Cherry1,2 , J. Jacob Culp1,3 , Kathryn E. Perez1,4 , Jeff B. Pollock1 , D, mangroves, seagrass macroalgal beds, as well as tidal creeks; Dahlgren and Marr 2004), have been identified

  1. Tidally driven ice speed variation at Helheim Glacier, Greenland, observed with terrestrial radar interferometry

    E-Print Network [OSTI]

    Holland, David

    Tidally driven ice speed variation at Helheim Glacier, Greenland, observed with terrestrial radar Space Flight Center, Greenbelt, MD, USA 4 Earth System Science Interdisciplinary Center, University is usually packed with dense ice melange. Helheim Glacier accelerated and retreated between 2000 and 2005

  2. Transformations of galaxies. III. Encounter dynamics and tidal response as functions of galaxy structure

    E-Print Network [OSTI]

    Barnes, Joshua E

    2015-01-01

    Tidal interactions between disc galaxies depend on galaxy structure, but the details of this relationship are incompletely understood. I have constructed a three-parameter grid of bulge/disc/halo models broadly consistent with $\\Lambda$CDM, and simulated an extensive series of encounters using these models. Halo mass and extent strongly influence the dynamics of orbit evolution. In close encounters, the transfer of angular momentum mediated by the dynamical response of massive, extended haloes can reverse the direction of orbital motion of the central galaxies after their first passage. Tidal response is strongly correlated with the ratio $v_\\mathrm{e} / v_\\mathrm{c}$ of escape to circular velocity within the participating discs. Moreover, the same ratio also correlates with the rate at which tidal tails are reaccreted by their galaxies of origin; consequently, merger remnants with `twin tails', such as NGC 7252, may prove hard to reproduce unless $(v_\\mathrm{e} / v_\\mathrm{c})^2 \\lesssim 5.5$. The tidal morp...

  3. TIDAL INTERACTION AS THE ORIGIN OF EARLY-TYPE DWARF GALAXIES IN GROUP ENVIRONMENTS

    SciTech Connect (OSTI)

    Paudel, Sanjaya; Ree, Chang H.

    2014-11-20

    We present a sample of dwarf galaxies that suffer ongoing disruption by the tidal forces of nearby massive galaxies. By analyzing structural and stellar population properties using the archival imaging and spectroscopic data from the Sloan Digital Sky Survey (SDSS), we find that they are likely a ''smoking gun'' example of the formation through tidal stirring of early-type dwarf galaxies (dEs) in the galaxy group environment. The inner cores of these galaxies are fairly intact and the observed light profiles are well fit by the Sérsic functions while the tidally stretched stellar halos are prominent in the outer parts. They are all located within a sky-projected distance of 50 kpc from the centers of the host galaxies and no dwarf galaxies have relative line-of-sight velocities larger than 205 km s{sup –1} to their hosts. We derive the Composite Stellar Population properties of these galaxies by fitting the SDSS optical spectra to a multiple-burst composite stellar population model. We find that these galaxies accumulate a significant fraction of stellar mass within the last 1 Gyr and contain a majority stellar population with an intermediate age of 2 to 4 Gyr. Based on this evidence, we argue that tidal stirring, particularly through the galaxy-galaxy interaction, might have an important role in the formation and evolution of dEs in the group environment where the influence of other gas stripping mechanism might be limited.

  4. Tidal wave in 102Pd: Rotating condensate of up to seven d-bosons

    E-Print Network [OSTI]

    S. Frauendorf; M. A. Caprio; J. Sun

    2012-02-08

    The yrast states of even even vibrational and transitional nuclei are inter- preted as a rotating condensate of interacting d-bosons and the corresponding semi-classical tidal wave concept. A simple experimental manifestation of the anharmonicity caused by the boson interaction is found. The interpretation is substantiated by calculations based on the Collective Model and the Cranking Model.

  5. Nekton Density Patterns in Tidal Ponds and Adjacent Wetlands Related to Pond Size and Salinity

    E-Print Network [OSTI]

    Nekton Density Patterns in Tidal Ponds and Adjacent Wetlands Related to Pond Size and Salinity pond sizes (diameter 750 m=large), and two habitat types (pond, adjacent marsh) in the Barataria Bay Estuary, Louisiana. Nekton assemblages of ponds and the adjacent marsh

  6. Covariation of coastal water temperature and microbial pollution at interannual to tidal periods

    E-Print Network [OSTI]

    Winant, Clinton D.

    Covariation of coastal water temperature and microbial pollution at interannual to tidal periods. G. Monismith (2004), Covariation of coastal water temperature and microbial pollution at interannual the relationship between water temperature and fecal pollution in the surf zone at Huntington and Newport Beach

  7. An Alternative Model for the Tidal Evolution of the Earth-Moon-Sun System

    E-Print Network [OSTI]

    Arbab I. Arbab

    2007-09-12

    We have found that the expansion of the universe has immense consequences on our local systems. We present a model based on cosmic expansion that fits well with observation. The close approach problem inflicting tidal theory is averted in this model. We have shown that the astronomical and geological changes of our local systems are of the order of Hubble constant.

  8. Asymmetric mixing transport: a horizontal transport mechanism for sinking plankton and sediment in tidal flows

    E-Print Network [OSTI]

    Pringle, James "Jamie"

    Asymmetric mixing transport: a horizontal transport mechanism for sinking plankton and sediment in tidal flows James M. Pringle1 and Peter J.S. Franks2 SIO-UCSD, Mail Stop 0218 La Jolla, California 92093-0218 Running Head: Asymmetric Mixing Transport and Plankton 1 jmpringle@ucsd.edu 2 pfranks@ucsd.edu 1 #12

  9. Research papers Assessment of coastal density gradients near a macro-tidal estuary

    E-Print Network [OSTI]

    Polton, Jeff

    Oceanography Centre, Joseph Proudman Building, 6 Brownlow Street, Liverpool L3 5DA, UK a r t i c l e i n f o of a variety of factors ­ time and spatial (horizontal and vertical) scales are small, tidal currents factor, with wind forcing tending to reinforce it for wind speeds greater than 5­10 m sÀ1 . Near bed

  10. OES-IA Annex IV: Environmental Effects of Marine and Hydrokinetic Devices - Report from the Experts’ Workshop September 27th – 28th 2010 Clontarf Castle, Dublin Ireland

    SciTech Connect (OSTI)

    Copping, Andrea E.; O'Toole, Michael J.

    2010-12-02

    An experts' workshop was convened in Dublin Ireland September 27th – 28th 2010 in support of IEA Ocean Energy Systems Implementing Agreement Annex IV. PNNL was responsible for organizing the content of the workshop, overseeing the contractors (Irish Marine Institute) hosting the event, presenting material on Annex IV and materials applicable to the workshop intent. PNNL is also overseeing a contractor (Wave Energy Center/University of Plymouth – WEC/UP) in the collection and analysis of the Annex IV data. Fifty-eight experts from 8 countries attended the workshop by invitation, spending two days discussing the needs of Annex IV. Presentations by DOE (background on Annex IV), PNNL (process for developing Annex IV; presentation of the draft database for PNNL project, plans for incorporating Annex IV data), WEC/UP on the environmental effect matrix, and four MHK developers (two from the UK, one from Ireland and one from Sweden; each discussing their own projects and lessons learned for measuring and mitigating environmental effects, as well as interactions with consenting [permitting] processes) helped provide background. The workshop participants worked part of the time in the large group and most of the time in four smaller breakout groups. Participants engaged in the process and provided a wealth of examples of MHK environmental work, particularly in the European nations. They provided practical and actionable advice on the following: • Developing the Annex IV database, with specific uses and audiences • Strong consensus that we should collect detailed metadata on available data sets, rather than attempting to draw in copious datasets. The participants felt there would then be an opportunity to then ask for specific set of data as needed, with specific uses and ownership of the data specified. This is particularly important as many data collected, particularly in Europe but also in Canada, are proprietary; developers were not comfortable with the idea of handing over all their environmental effects data, but all said they would entertain the request if they specifics were clear. • The recommendation was to collect metadata via an online interactive form, taking no more than one hour to complete. • Although the idea of cases representing the “best practices” was recognized as useful, the participants pointed out that there are currently so few MHK projects in the water, that any and all projects were appropriate to highlight as “cases”. There was also discomfort at the implication that “best practices” implied “lesser practices”; this being unhelpful to a new and emerging industry. • Workshop participants were asked if they were willing to continue to engage in the Annex IV process; all expressed willingness. The workshop was successful in adequately addressing its objectives and through participation and interaction in the breakout sessions around the various topics. As a result of the workshop, many delegates are now better informed and have a greater understanding of the potential environmental effects of MHK devices on the marine environment. There is now a greater sense of understanding of the issues involved and consensus by those regulators, developers and scientists who attended the workshop. A strong network has also been built over the two days between European and US/Canadian technical experts in wave and tidal energy.

  11. General Relativistic Hydrodynamic Simulation of Accretion Flow from a Stellar Tidal Disruption

    E-Print Network [OSTI]

    Hotaka Shiokawa; Julian H. Krolik; Roseanne M. Cheng; Tsvi Piran; Scott C. Noble

    2015-01-18

    We study how the matter dispersed when a supermassive black hole tidally disrupts a star joins an accretion flow. Combining a relativistic hydrodynamic simulation of the stellar disruption with a relativistic hydrodynamics simulation of the tidal debris motion, we track such a system until ~80% of the stellar mass bound to the black hole has settled into an accretion flow. Shocks near the stellar pericenter and also near the apocenter of the most tightly-bound debris dissipate orbital energy, but only enough to make the characteristic radius comparable to the semi-major axis of the most-bound material, not the tidal radius as previously thought. The outer shocks are caused by post-Newtonian effects, both on the stellar orbit during its disruption and on the tidal forces. Accumulation of mass into the accretion flow is non-monotonic and slow, requiring ~3--10x the orbital period of the most tightly-bound tidal streams, while the inflow time for most of the mass may be comparable to or longer than the mass accumulation time. Deflection by shocks does, however, remove enough angular momentum and energy from some mass for it to move inward even before most of the mass is accumulated into the accretion flow. Although the accretion rate rises sharply and then decays roughly as a power-law, its maximum is ~0.1x the previous expectation, and the duration of the peak is ~5x longer than previously predicted. The geometric mean of the black hole mass and stellar mass inferred from a measured event timescale is therefore ~0.2x the value given by classical theory.

  12. Effects of Electromagnetic Fields on Fish and Invertebrates: Task 2.1.3: Effects on Aquatic Organisms - Fiscal Year 2011 Progress Report - Environmental Effects of Marine and Hydrokinetic Energy

    SciTech Connect (OSTI)

    Woodruff, Dana L.; Schultz, Irvin R.; Marshall, Kathryn E.; Ward, Jeffrey A.; Cullinan, Valerie I.

    2012-05-01

    This fiscal year (FY) 2011 progress report (Task 2.1.3 Effects on Aquatic Organisms, Subtask 2.3.1.1 Electromagnetic Fields) describes studies conducted by PNNL as part of the DOE Wind and Water Power Program to examine the potential effects of electromagnetic fields (EMF) from marine and hydrokinetic devices on aquatic organisms, including freshwater and marine fish and marine invertebrates. In this report, we provide a description of the methods and results of experiments conducted in FY 2010-FY 2011 to evaluate potential responses of selected aquatic organisms. Preliminary EMF laboratory experiments during FY 2010 and 2011 entailed exposures with representative fish and invertebrate species including juvenile coho salmon (Oncorhynchus kisutch), Atlantic halibut (Hippoglossus hippoglossus), California halibut (Paralicthys californicus), rainbow trout (Oncorhynchus mykiss), and Dungeness crab (Metacarcinus magister). These species were selected for their ecological, commercial, and/or recreational importance, as well as their potential to encounter an MHK device or transmission cable during part or all of their life cycle. Based on previous studies, acute effects such as mortality were not expected to occur from EMF exposures. Therefore, our measurement endpoints focused on behavioral responses (e.g., detection of EMF, interference with feeding behavior, avoidance or attraction to EMF), developmental changes (i.e., growth and survival from egg or larval stage to juvenile), and exposure markers indicative of physiological responses to stress. EMF intensities during the various tests ranged from 0.1 to 3 millitesla, representing a range of upper bounding conditions reported in the literature. Experiments to date have shown there is little evidence to indicate distinct or extreme behavioral responses in the presence of elevated EMF for the species tested. Several developmental and physiological responses were observed in the fish exposures, although most were not statistically significant. Additional species are currently planned for laboratory testing in the next fiscal year (e.g. an elasmobranch, American lobster) to provide a broader assessment of species important to stakeholders. The collective responses of all species will be assessed in terms of life stage, exposure scenarios, and biological relevance, to address current uncertainties related to effects of EMF on aquatic organisms.

  13. Tidal Disruption Flares as the Source of Ultra-high Energy Cosmic Rays

    E-Print Network [OSTI]

    Glennys R. Farrar

    2012-10-03

    The optical spectral energy distributions of two tidal disruption flares identified by van Velzen et al. (2011) in archival SDSS data, are found to be well-fit by a thin-accretion-disk model. Furthermore, the inferred Supermassive Black Hole mass values agree well with the SMBH masses estimated from the host galaxy properties. Integrating the model SEDs to include shorter wavelength contributions provides an estimate of the bolometric luminosities of the accretion disks. The resultant bolometric luminosities are well in excess of the minimum required for accelerating UHECR protons. In combination with the recent observational estimate of the TDF rate (van Velzen and Farrar, these Proceedings), the results presented here strengthen the case that transient jets formed in tidal disruption events may be responsible for accelerating all or most UHECRs.

  14. The X-ray through Optical Fluxes and Line Strengths of Tidal Disruption Events

    E-Print Network [OSTI]

    Roth, Nathaniel; Guillochon, James; Ramirez-Ruiz, Enrico

    2015-01-01

    Observations of luminous flares resulting from the possible tidal disruption of stars by supermassive black holes have raised a number of puzzles. Outstanding questions include the origin of the optical and ultraviolet (UV) flux, the weakness of hydrogen lines in the spectrum, and the occasional simultaneous observation of x-rays. Here we study the emission from tidal disruption events (TDEs) produced as radiation from black hole accretion propagates through an extended, optically thick envelope formed from stellar debris. We analytically describe key physics controlling spectrum formation, and present detailed radiative transfer calculations that model the spectral energy distribution (SED) and optical line strengths of TDEs near peak brightness. The steady-state transfer is coupled to a non local thermodynamic equilibrium treatment of the excitation and ionization states of hydrogen, helium and oxygen (as a representative metal). Our calculations show how an extended envelope can reprocess a fraction of sof...

  15. Tidal Disruption Flares as the Source of Ultra-high Energy Cosmic Rays

    E-Print Network [OSTI]

    Farrar, Glennys R

    2012-01-01

    The optical spectral energy distributions of two tidal disruption flares identified by van Velzen et al. (2011) in archival SDSS data, are found to be well-fit by a thin-accretion-disk model. Furthermore, the inferred Supermassive Black Hole mass values agree well with the SMBH masses estimated from the host galaxy properties. Integrating the model SEDs to include shorter wavelength contributions provides an estimate of the bolometric luminosities of the accretion disks. The resultant bolometric luminosities are well in excess of the minimum required for accelerating UHECR protons. In combination with the recent observational estimate of the TDF rate (van Velzen and Farrar, these Proceedings), the results presented here strengthen the case that transient jets formed in tidal disruption events may be responsible for accelerating all or most UHECRs.

  16. CONSTRAINING TIDAL DISSIPATION IN STARS FROM THE DESTRUCTION RATES OF EXOPLANETS

    SciTech Connect (OSTI)

    Penev, Kaloyan; Jackson, Brian; Spada, Federico; Thom, Nicole

    2012-06-01

    We use the distribution of extrasolar planets in circular orbits around stars with surface convective zones detected by ground-based transit searches to constrain how efficiently tides raised by the planet are dissipated on the parent star. We parameterize this efficiency as a tidal quality factor (Q{sub *}). We conclude that the population of currently known planets is inconsistent with Q{sub *} < 10{sup 7} at the 99% level. Previous studies show that values of Q{sub *} between 10{sup 5} and 10{sup 7} are required in order to explain the orbital circularization of main-sequence low-mass binary stars in clusters, suggesting that different dissipation mechanisms might be acting in the two cases, most likely due to the very different tidal forcing frequencies relative to the stellar rotation frequency occurring for star-star versus planet-star systems.

  17. Non-linear evolution of the angular momentum of protostructures from tidal torques

    E-Print Network [OSTI]

    Paolo Catelan; Tom Theuns

    1996-04-15

    We discuss the non-linear evolution of the angular momentum L acquired by protostructures, like protogalaxies and protoclusters, due to tidal interactions with the surrounding matter inhomogeneities. The primordial density distribution is assumed to be Gaussian and the non-linear dynamics of the collisionless mass fluid is followed using Lagrangian perturbation theory. For a Cold Dark Matter spectrum, the inclusion of the leading-order Lagrangian correction terms results in a value of the rms ensemble average ^{1/2} which is only a factor of 1.3 higher than the corresponding linear estimate, irrespective of the scale. Consequently, the predictions of linear theory are rather accurate in quantifying the evolution of the angular momentum of protostructures before collapse sets in. In the Einstein-de Sitter universe, the initial torque is a good estimate for the tidal torque over the whole period during which the object is spun up.

  18. Three-dimensional Numerical Analysis on Blade Response of Vertical Axis Tidal Current Turbine Under Operational Condition

    SciTech Connect (OSTI)

    Li, Ye; Karri, Naveen K.; Wang, Qi

    2014-04-30

    Tidal power as a large-scale renewable source of energy has been receiving significant attention recently because of its advantages over the wind and other renewal energy sources. The technology used to harvest energy from tidal current is called a tidal current turbine. Though some of the principles of wind turbine design are applicable to tidal current turbines, the design of latter ones need additional considerations like cavitation damage, corrosion etc. for the long-term reliability of such turbines. Depending up on the orientation of axis, tidal current turbines can be classified as vertical axis turbines or horizontal axis turbines. Existing studies on the vertical axis tidal current turbine focus more on the hydrodynamic aspects of the turbine rather than the structural aspects. This paper summarizes our recent efforts to study the integrated hydrodynamic and structural aspects of the vertical axis tidal current turbines. After reviewing existing methods in modeling tidal current turbines, we developed a hybrid approach that combines discrete vortex method -finite element method that can simulate the integrated hydrodynamic and structural response of a vertical axis turbine. This hybrid method was initially employed to analyze a typical three-blade vertical axis turbine. The power coefficient was used to evaluate the hydrodynamic performance, and critical deflection was considered to evaluate the structural reliability. A sensitivity analysis was also conducted with various turbine height-to-radius ratios. The results indicate that both the power output and failure probability increase with the turbine height, suggesting a necessity for optimal design. An attempt to optimize a 3-blade vertical axis turbine design with hybrid method yielded a ratio of turbine height to radius (H/R) about 3.0 for reliable maximum power output.

  19. Structural Design of a Horizontal-Axis Tidal Current Turbine Composite Blade

    SciTech Connect (OSTI)

    Bir, G. S.; Lawson, M. J.; Li, Y.

    2011-10-01

    This paper describes the structural design of a tidal composite blade. The structural design is preceded by two steps: hydrodynamic design and determination of extreme loads. The hydrodynamic design provides the chord and twist distributions along the blade length that result in optimal performance of the tidal turbine over its lifetime. The extreme loads, i.e. the extreme flap and edgewise loads that the blade would likely encounter over its lifetime, are associated with extreme tidal flow conditions and are obtained using a computational fluid dynamics (CFD) software. Given the blade external shape and the extreme loads, we use a laminate-theory-based structural design to determine the optimal layout of composite laminas such that the ultimate-strength and buckling-resistance criteria are satisfied at all points in the blade. The structural design approach allows for arbitrary specification of the chord, twist, and airfoil geometry along the blade and an arbitrary number of shear webs. In addition, certain fabrication criteria are imposed, for example, each composite laminate must be an integral multiple of its constituent ply thickness. In the present effort, the structural design uses only static extreme loads; dynamic-loads-based fatigue design will be addressed in the future. Following the blade design, we compute the distributed structural properties, i.e. flap stiffness, edgewise stiffness, torsion stiffness, mass, moments of inertia, elastic-axis offset, and center-of-mass offset along the blade. Such properties are required by hydro-elastic codes to model the tidal current turbine and to perform modal, stability, loads, and response analyses.

  20. Newtonian wormholes with spherical symmetry and tidal forces on test particles

    E-Print Network [OSTI]

    Paulo Luz; José P. S. Lemos

    2015-05-23

    A spherically symmetric wormhole in Newtonian gravitation in curved space, enhanced with a connection between the mass density and the Ricci scalar, is presented. The wormhole, consisting of two connected asymptotically flat regions, inhabits a spherically symmetric curved space. The gravitational potential, gravitational field and the pressure that supports the fluid that permeates the Newtonian wormhole are computed. Particle dynamics and tidal effects in this geometry are studied. The possibility of having Newtonian black holes in this theory is sketched.

  1. Tidal salt marshes of the southeast Atlantic Coast: A community profile

    SciTech Connect (OSTI)

    Wiegert, R.G.; Freeman, B.J.

    1990-09-01

    This report is part of a series of community profiles on the ecology of wetland and marine communities. This particular profile considers tidal marshes of the southeastern Atlantic coast, from North Carolina south to northern Florida. Alone among the earth's ecosystems, coastal communities are subjected to a bidirectional flooding sometimes occurring twice each day; this flooding affects successional development, species composition, stability, and productivity. In the tidally influenced salt marsh, salinity ranges from less than 1 ppt to that of seawater. Dominant plant species include cordgrasses (Spartina alterniflora and S. cynosuroides), black needlerush (Juncus romerianus), and salt marsh bulrush (Scirpus robustus). Both terrestrail and aquatic animals occur in salt marshes and include herons, egrets ospreys (Pandion haliaetus), bald eagles (Haliaeetus leucocephalus), alligators (Alligator Mississippiensis), manatees (Trichecus manatus), oysters, mussels, and fiddler crabs. Currently, the only significant direct commercial use of the tidal salt marshes is by crabbers seeking the blue crab Callinectes sapidus, but the marshes are quite important recreationally, aesthetically, and educationally. 151 refs., 45 figs., 6 tabs.

  2. Tidal torques dynamical friction and the structure of clusters of galaxies

    E-Print Network [OSTI]

    A. Del Popolo; M. Gambera

    2001-05-22

    We study the joint effect of tidal torques and dynamical friction on the collapse of density peaks solving numerically the equations of motion of a shell of barionic matter falling into the central regions of a cluster of galaxies. We calculate the evolution of the expansion parameter, a(t), of the perturbation using a coefficient of dynamical friction eta_{cl} obtained from a clustered system and taking into account the gravitational interaction of the quadrupole moment of the system with the tidal field of the matter of the neighboring proto-galaxies. We show that within high-density environments, such as rich clusters of galaxies, tidal torques and dynamical friction slow down the collapse of low-nu peaks producing an observable variation of the parameter of expansion of the shell. As a consequence a bias of dynamical nature arises because high-density peaks preferentially collapse to form halos within which visible objects eventually will condense. For a standard Cold Dark Matter model this dynamical bias can account for a substantial part of the total bias required by observations on cluster scales.

  3. Tidally dominated depositional environment for the Mt. Simon Sandstone in central Illinois

    SciTech Connect (OSTI)

    Sargent, M.L.; Lasemi, Z. (Illinois State Geological Survey, Champaign, IL (United States))

    1993-03-01

    Several hundred feet of core from the upper part of the Mt. Simon in central Illinois have been examined macroscopically. Grain sizes and their systematics, bedding characteristics, sedimentary structures, and relationships among beds show that the upper Mt. Simon Sandstone is composed of a series of fining-upward cycles up to 10 m (30 feet) thick. A typical cycle consists, in ascending order, of a sandy subtidal facies, a mixed sand and mud intertidal-flat facies, and a muddy upper tidal-flat facies upward through the succession, the maximum and average grain size becomes progressively finer and the cycles thinner. The lower sandstone of each cycle contains beds that are massive to cross bedded and cross laminated; some beds show scoured reactivation surfaces. A few cycles contain a middle unit characterized by flaser and lenticular bedding and abundant mudcracks. Mudcracks also are common in the shale beds at the top of each cycle. Sedimentary structures such as reactivation surfaces, flaser and lenticular bedding, and mudcracks suggest that these cycles were deposited in peritidal environments. The presence of Skolithos in some cycles suggests very shallow marine conditions. The within-cycle upward fining is caused by regression or progradation that reflects a progressive decrease in current velocity from subtidal to intertidal parts of the tidal flat. Frequent flooding of the tidal flat resulted in repeated fining-upward cycles within the upper part of the Mt. Simon Sandstone.

  4. Avian Communities in Tidal Salt Marshes of San Francisco Bay: A Review of Functional Groups by Foraging Guild and Habitat Association

    E-Print Network [OSTI]

    2011-01-01

    2006). San Francisco Bay song spar- rows are adapted to highswallows (Hirundinidae), savannah spar- rows (Passerculussurvival in tidal-marsh song spar- rows was maximized when

  5. The variation of the tidal quality factor of convective envelopes of rotating low-mass stars along their evolution

    E-Print Network [OSTI]

    Mathis, S

    2015-01-01

    More than 1500 exoplanets have been discovered around a large diversity of host stars (from M- to A-type stars). Tidal dissipation in their convective envelope is a key actor that shapes the orbital architecture of short-period systems and that still remains unknown. Using a simplified two-layer assumption and grids of stellar models, we compute analytically an equivalent modified tidal quality factor, which is proportional to the inverse of the frequency-averaged dissipation due to the viscous friction applied by turbulent convection on tidal waves. It leads the conversion of their kinetic energy into heat and tidal evolution of orbits and spin. During their Pre-Main-Sequence, all low-mass stars have a decrease of the equivalent modified tidal quality factor for a fixed angular velocity of their convective envelope. Next, it evolves on the Main Sequence to an asymptotic value that is minimum for $0.6M_{\\odot}$ K-type stars and that increases by several orders of magnitude with increasing stellar mass. Finall...

  6. Tidal disruption jets as the source of Ultra-High Energy Cosmic Rays

    E-Print Network [OSTI]

    Farrar, Glennys R

    2014-01-01

    Observations of the spectacular, blazar-like tidal disruption event (TDE) candidates Swift J1644+57 and J2058+05 show that the conditions required for accelerating protons to 10^{20} eV appear to be realized in the outer jet, and possibly in the inner jet as well. Direct and indirect estimates of the rate of jetted-TDEs, and of the energy they inject, are compatible with the observed flux of ultra-high energy cosmic rays (UHECRs) and the abundance of presently contributing sources. Thus TDE-jets can be a major source of UHECRs, even compabile with a pure proton composition.

  7. Tidal Waves in $^{102}$Pd: A Rotating Condensate of Multiple $d$ bosons

    E-Print Network [OSTI]

    A. D. Ayangeakaa; U. Garg; M. A. Caprio; M. P. Carpenter; S. S. Ghugre; R. V. F. Janssens; F. G. Kondev; J. T. Matta; S. Mukhopadhyay; D. Patel; D. Seweryniak; J. Sun; S. Zhu; S. Frauendorf

    2013-02-02

    Low-lying collective excitations in even-even vibrational and transitional nuclei may be described semi-classically as quadrupole running waves on the surface of the nucleus ("tidal waves"), and the observed vibrational-rotational behavior can be thought of as resulting from a rotating condensate of interacting $d$ bosons. These concepts have been investigated by measuring lifetimes of the levels in the yrast band of the $^{102}$Pd nucleus with the Doppler Shift Attenuation Method. The extracted $B(E2)$ reduced transition probabilities for the yrast band display a monotonic increase with spin, in agreement with the interpretation based on rotation-induced condensation of aligned $d$ bosons.

  8. Coherent Structures in Turbulent Flows: Experimental Studies on the Turbulence of Multiphase Plumes and Tidal Vortices 

    E-Print Network [OSTI]

    Bryant, Duncan Burnette

    2011-08-08

    stream_source_info BRYANT-DISSERTATION.pdf.txt stream_content_type text/plain stream_size 163756 Content-Encoding ISO-8859-1 stream_name BRYANT-DISSERTATION.pdf.txt Content-Type text/plain; charset=ISO-8859..., the turbulent energy spectra in inertial particle plumes followed the same modulation as the bubble plumes. PIV experiments from the tidal starting-jet vortices detail the influence of a finite channel length using identified vortice. The results show...

  9. MHK Projects/Fishers Island Tidal Energy Project | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource HistoryScenarios Towards 2050 JumpCoos Bay OPT WaveFishers Island Tidal Energy

  10. MHK Projects/Half Moon Cove Tidal Project | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource HistoryScenarios Towards 2050 JumpCoos Bay OPTHalf Moon Cove Tidal Project <

  11. MHK Projects/Hammerfest Strom UK Tidal Stream | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource HistoryScenarios Towards 2050 JumpCoos Bay OPTHalf Moon Cove Tidal Project

  12. Assessment of Energy Production Potential from Tidal Streams in the United States

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergyTher i n c i p a l De p u tCorporationIt's Potential from Tidal Streams in the United

  13. A Synthesis of Environmental and Plant Community Data for Tidal Wetland Restoration Planning in the Lower Columbia River and Estuary

    SciTech Connect (OSTI)

    Diefenderfer, Heida L.; Borde, Amy B.; Cullinan, Valerie I.

    2013-12-01

    This report reanalyzes and synthesizes previously existing environmental and plant community data collected by PNNL at 55 tidal wetlands and 3 newly restored sites in the lower Columbia River and estuary (LCRE) between 2005 and 2011. Whereas data were originally collected for various research or monitoring objectives of five studies, the intent of this report is to provide only information that will have direct utility in planning tidal wetland restoration projects. Therefore, for this report, all tidal wetland data on plants and the physical environment, which were originally developed and reported by separate studies, were tabulated and reanalyzed as a whole. The geographic scope of the data collected in this report is from Bonneville Lock and Dam to the mouth of the Columbia River

  14. Tidal sampler

    DOE Patents [OSTI]

    Hayes, David W. (Aiken, SC)

    1978-01-01

    An apparatus for pumping a sample of water or other liquid that uses the energy generated from the rise and fall of the liquid level to force a sample of the liquid into a collection vessel. A suction vessel and booster vessel with interconnecting tubing and check valves are responsive to an oscillating liquid level to pump a portion of said liquid into a collection vessel.

  15. A scaling relation of the evolving tidal fields in a ?CDM cosmology

    SciTech Connect (OSTI)

    Lee, Jounghun [Astronomy Program, FPRD, Department of Physics and Astronomy, Seoul National University, Seoul 151-747 (Korea, Republic of); Springel, Volker, E-mail: jounghun@astro.snu.ac.kr, E-mail: volker@mpa-garching.mpg.de [Max-Planck Institut fuer Astrophysik, Karl-Schwarzschild Strasse 1, D-85748 Garching (Germany)

    2010-05-01

    We report the finding of a scaling relation among the cosmic-web anisotropy parameter A, the linear density rms fluctuation ?(r) and the linear growth factor D(z). Using the tidal field derived from the Millennium Simulation on 512{sup 3} grids at z = 0,2,5 and 127, we calculate the largest eigenvalues ? of the local tidal tensor at each grid resolution and measure its distance-averaged two-point correlation function, ?{sub ?}, as a function of the cosines of polar angles cos ? in the local principal axis frame. We show that ?{sub ?} is quite anisotropic, increasing toward the directions of minimal matter compression, and that the anisotropy of ?{sub ?} increases as the redshift z decreases and as the upper distance cutoff r{sub c} decreases. Fitting the numerical results to an analytic fitting model ?{sub ?}(cos ?)?(1+Acos {sup n}?){sup ?1}, it is found that the best fit value of A, dubbed the cosmic-web anisotropy parameter, varies systematically with ?(r{sub c}) and D(z), allowing us to determine the simple empiral scaling relation A(r{sub c},z) = 0.8 D{sup 0.76}(z) ?(r{sub c})

  16. On large and small tidal lags. The virtual identity of two rheophysical theories

    E-Print Network [OSTI]

    Ferraz-Mello, Sylvio

    2015-01-01

    The aim of this letter is to discuss the virtual identity of two recent tidal theories: the creep tide theory of Ferraz-Mello (Cel. Mech. Dyn. Astron. 116, 109, 2013) and the Maxwell model developed by Correia et al. (Astron. Astrophys. 571, A50, 2014). It includes the discussion of the basic equations of the theories, which, in both cases, include an elastic and an anelastic component, and shows that the basic equations of the two theories are equivalent and differ by only a numerical factor in the anelastic tide. It also includes a discussion of the lags: the lag of the full tide (geodetic), dominated by the elastic component, and the phase of the anelastic tide. In rotating rocky bodies not trapped in a spin-orbit resonance (e.g., the Earth) the geodetic lag is close to zero and the phase of the anelastic tide is close to 90 degrees. The results obtained from combining tidal solutions from satellite tracking data and from Topex/Poseidon satellite altimeter data, by Ray et al., are extended to determine the...

  17. A STATISTICAL METHOD FOR MEASURING THE GALACTIC POTENTIAL AND TESTING GRAVITY WITH COLD TIDAL STREAMS

    SciTech Connect (OSTI)

    Penarrubia, Jorge; Walker, Matthew G.

    2012-11-20

    We introduce the Minimum Entropy Method, a simple statistical technique for constraining the Milky Way gravitational potential and simultaneously testing different gravity theories directly from 6D phase-space surveys and without adopting dynamical models. We demonstrate that orbital energy distributions that are separable (i.e., independent of position) have an associated entropy that increases under wrong assumptions about the gravitational potential and/or gravity theory. Of known objects, 'cold' tidal streams from low-mass progenitors follow orbital distributions that most nearly satisfy the condition of separability. Although the orbits of tidally stripped stars are perturbed by the progenitor's self-gravity, systematic variations of the energy distribution can be quantified in terms of the cross-entropy of individual tails, giving further sensitivity to theoretical biases in the host potential. The feasibility of using the Minimum Entropy Method to test a wide range of gravity theories is illustrated by evolving restricted N-body models in a Newtonian potential and examining the changes in entropy introduced by Dirac, MONDian, and f(R) gravity modifications.

  18. Discovery of an outflow from radio observations of the tidal disruption event ASASSN-14li

    E-Print Network [OSTI]

    Alexander, Kate D; Guillochon, James; Zauderer, Bevin A; Williams, Peter K G

    2015-01-01

    The tidal disruption of stars by supermassive black holes (SMBH) lights up dormant systems and can be used to probe accretion and outflow processes. Theoretical calculations indicate that most tidal disruption events (TDEs) lead to super-Eddington accretion, which in turn drives outflows. The discovery of luminous radio emission from the $\\gamma$-ray TDE Sw J1644+57 revealed the formation of a relativistic jetted outflow, but such events represent $\\lesssim 1\\%$ of the TDE population. Direct evidence for outflows in the bulk of the TDE population, discovered through optical, ultraviolet (UV), and X-ray observations, has been lacking. Here we report the discovery of transient radio emission from the nearby optically-discovered TDE ASASSN-14li (distance of 90 Mpc), making it the first normal TDE detected in the radio, and unambiguously pointing to the formation of a non-relativistic outflow with a kinetic energy of $\\approx 10^{48}$ erg, a velocity of $\\approx 12,000-39,000$ km s$^{-1}$, and a mass of $\\approx ...

  19. Revealing the escape mechanism of three-dimensional orbits in a tidally limited star cluster

    E-Print Network [OSTI]

    Euaggelos E. Zotos

    2014-11-18

    The aim of this work is to explore the escape process of three-dimensional orbits in a star cluster rotating around its parent galaxy in a circular orbit. The gravitational field of the cluster is represented by a smooth, spherically symmetric Plummer potential, while the tidal approximation was used to model the steady tidal field of the galaxy. We conduct a thorough numerical analysis distinguishing between regular and chaotic orbits as well as between trapped and escaping orbits, considering only unbounded motion for several energy levels. It is of particular interest to locate the escape basins towards the two exit channels and relate them with the corresponding escape times of the orbits. For this purpose, we split our investigation into three cases depending on the initial value of the $z$ coordinate which was used for launching the stars. The most noticeable finding is that the majority of stars initiated very close to the primary $(x,y)$ plane move in chaotic orbits and they remain trapped for vast time intervals, while orbits with relatively high values of $z_0$ on the other hand, form well-defined basins of escape. It was also observed, that for energy levels close to the critical escape energy the escape rates of orbits are large, while for much higher values of energy most of the orbits have low escape periods or they escape immediately to infinity. We hope our outcomes to be useful for a further understanding of the dissolution process and the escape mechanism in open star clusters.

  20. A tidal disruption event in a nearby galaxy hosting an intermediate mass black hole

    SciTech Connect (OSTI)

    Donato, D.; Troja, E.; Pursimo, T.; Cheung, C. C.; Kutyrev, A.; Landt, H.; Butler, N. R.

    2014-02-01

    We report the serendipitous discovery of a bright point source flare in the Abell cluster A1795 with archival EUVE and Chandra observations. Assuming the EUVE emission is associated with the Chandra source, the X-ray 0.5-7 keV flux declined by a factor of ?2300 over a time span of 6 yr, following a power-law decay with index ?2.44 ± 0.40. The Chandra data alone vary by a factor of ?20. The spectrum is well fit by a blackbody with a constant temperature of kT ? 0.09 keV (?10{sup 6} K). The flare is spatially coincident with the nuclear region of a faint, inactive galaxy with a photometric redshift consistent at the 1? level with the cluster (z = 0.062476). We argue that these properties are indicative of a tidal disruption of a star by a black hole (BH) with log (M {sub BH}/M {sub ?}) ? 5.5 ± 0.5. If so, such a discovery indicates that tidal disruption flares may be used to probe BHs in the intermediate mass range, which are very difficult to study by other means.

  1. Gravitational acceleration and tidal effects in spherical-symmetric density profiles

    E-Print Network [OSTI]

    Caimmi, R

    2015-01-01

    Pure power-law density profiles, $\\rho(r)\\propto r^{b-3}$, are classified in connection with the following reference cases: (i) isodensity, $b=3$, $\\rho=$ const; (ii) isogravity, $b=2$, $g=$ const; (iii) isothermal, $b=1$, $v=[GM(r)/r]^{1/2}=$ const; (iv) isomass, $b=0$, $M=$ const. A restricted number of different families of density profiles including, in addition, cored power-law, generalized power-law, polytropes, are studied in detail with regard to both one-component and two-component systems. Considerable effort is devoted to the existence of an extremum point (maximum absolute value) in the gravitational acceleration within the matter distribution. Predicted velocity curves are compared to the data inferred from observations. Tidal effects on an inner subsystem are investigated and an application is made to globular clusters within the Galaxy. To this aim, the tidal radius is defined by balancing the opposite gravitational forces from the Galaxy and the selected cluster on a special point of the clust...

  2. Ultra-Close Encounters of Stars With Massive Black Holes: Tidal Disruption Events With Prompt Hyperaccretion

    E-Print Network [OSTI]

    Christopher Evans; Pablo Laguna; Michael Eracleous

    2015-06-01

    A bright flare from a galactic nucleus followed at late times by a $t^{-5/3}$ decay in luminosity is often considered the signature of the complete tidal disruption of a star by a massive black hole. The flare and power-law decay are produced when the stream of bound debris returns to the black hole, self-intersects, and eventually forms an accretion disk or torus. In the canonical scenario of a solar-type star disrupted by a $10^{6}\\; M_\\odot$ black hole, the time between the disruption of the star and the formation of the accretion torus could be years. We present fully general relativistic simulations of a new class of tidal disruption events involving ultra-close encounters of solar-type stars with intermediate mass black holes. In these encounters, a thick disk forms promptly after disruption, on timescales of hours. After a brief initial flare, the accretion rate remains steady and highly super-Eddington for a few days at $\\sim 10^2\\,M_\\odot\\,{\\rm yr}^{-1}$.

  3. Illuminating Massive Black Holes With White Dwarfs: Orbital Dynamics and High Energy Transients from Tidal Interactions

    E-Print Network [OSTI]

    MacLeod, Morgan; Ramirez-Ruiz, Enrico; Guillochon, James; Samsing, Johan

    2014-01-01

    White dwarfs (WDs) can be tidally disrupted only by massive black holes (MBHs) with masses less than approximately $10^5 M_\\odot$. These tidal interactions feed material to the MBH well above its Eddington limit, with the potential to launch a relativistic jet. The corresponding beamed emission is a promising signpost to an otherwise quiescent MBH of relatively low mass. We show that the mass transfer history, and thus the lightcurve, are quite different when the disruptive orbit is parabolic, eccentric, or circular. The mass lost each orbit exponentiates in the eccentric-orbit case leading to the destruction of the WD after several tens of orbits and making it difficult to produce a Swift J1644+57-like lightcurve via this channel. We then examine the stellar dynamics of clusters surrounding these MBHs to show that single-passage WD disruptions are substantially more common than repeating encounters in eccentric orbits. The $10^{49}$ erg s$^{-1}$ peak luminosity of these events makes them visible to cosmologi...

  4. Probing the tidal disruption flares of massive black holes with high-energy neutrinos

    E-Print Network [OSTI]

    Wang, Xiang-Yu; Dai, Zi-Gao; Cheng, K S

    2011-01-01

    The recently discovered high-energy transient Swift J164449.3+573451 (Sw J1644+57) is thought to arise from the tidal disruption of a passing star by a dormant massive black hole. Modeling of the broadband emission suggests the presence of a powerful relativistic jet, which contributes dominantly to the observed X-ray emission. Here we suggest that high energy protons accelerated by internal shocks in the jets produce ~0.1-10 PeV neutrinos through photomeson interactions with X-ray photons. The large X-ray fluence (7*10^{-4} erg cm^{-2}) and high photopion efficiency, together with the insignificant cooling of secondary mesons, result in bright neutrino emission expected from Sw J1644+57 if the jet composition is matter-dominated. One to several neutrinos may be detected by a Km^3-scale detector from one tidal disruption event similar to Sw J1644+57, thereby providing a powerful probe of the composition of the jets.

  5. Infrared emission from tidal disruption events --- probing the pc-scale dust content around galactic nuclei

    E-Print Network [OSTI]

    Lu, Wenbin; Evans, Neal J

    2015-01-01

    Recent UV-optical surveys have been successful in finding tidal disruption events (TDEs), in which a star is tidally disrupted by a supermassive black hole (BH). These TDEs release a huge amount of radiation energy ~ 10^51-52 erg into the circum-nuclear medium. If the medium is dusty, most of the radiation energy will be absorbed by dust grains within ~ 1 pc from the BH and re-radiated in the infrared. We calculate the dust emission lightcurve from a 1-D radiative transfer model, taking into account the time-dependent heating, cooling and sublimation of dust grains. We show that the dust emission peaks at 3-10 microns and has typical luminosities ~ 10^42-43 erg/s (with sky covering factor of dusty clouds ranging from 0.1-1). This is detectable by current generation of telescopes. In the near future, James Webb Space Telescope will be able to perform photometric and spectroscopic measurements, in which silicate or polycyclic aromatic hydrocarbon (PAH) features may be found. Observations at rest-frame wavelengt...

  6. Using gaps in N-body tidal streams to probe missing satellites

    SciTech Connect (OSTI)

    Ngan, W. H. W.; Carlberg, R. G., E-mail: ngan@astro.utoronto.ca [Department of Astronomy and Astrophysics, University of Toronto, Toronto, ON M5S3H4 (Canada)

    2014-06-20

    We use N-body simulations to model the tidal disruption of a star cluster in a Milky-Way-sized dark matter halo, which results in a narrow stream comparable to (but slightly wider than) Pal-5 or GD-1. The mean Galactic dark matter halo is modeled by a spherical Navarro-Frenk-White potential with subhalos predicted by the ?CDM cosmological model. The distribution and mass function of the subhalos follow the results from the Aquarius simulation. We use a matched filter approach to look for 'gaps' in tidal streams at 12 length scales from 0.1 kpc to 5 kpc, which appear as characteristic dips in the linear densities along the streams. We find that, in addition to the subhalos' perturbations, the epicyclic overdensities (EOs) due to the coherent epicyclic motions of particles in a stream also produce gap-like signals near the progenitor. We measure the gap spectra—the gap formation rates as functions of gap length—due to both subhalo perturbations and EOs, which have not been accounted for together by previous studies. Finally, we project the simulated streams onto the sky to investigate issues when interpreting gap spectra in observations. In particular, we find that gap spectra from low signal-to-noise observations can be biased by the orbital phase of the stream. This indicates that the study of stream gaps will benefit greatly from high-quality data from future missions.

  7. OBLIQUITIES OF HOT JUPITER HOST STARS: EVIDENCE FOR TIDAL INTERACTIONS AND PRIMORDIAL MISALIGNMENTS

    SciTech Connect (OSTI)

    Albrecht, Simon; Winn, Joshua N.; Johnson, John A.; Howard, Andrew W.; Marcy, Geoffrey W.; Butler, R. Paul; Arriagada, Pamela; Crane, Jeffrey D.; Shectman, Stephen A.; Thompson, Ian B.; Hirano, Teruyuki; Bakos, Gaspar; Hartman, Joel D.

    2012-09-20

    We provide evidence that the obliquities of stars with close-in giant planets were initially nearly random, and that the low obliquities that are often observed are a consequence of star-planet tidal interactions. The evidence is based on 14 new measurements of the Rossiter-McLaughlin effect (for the systems HAT-P-6, HAT-P-7, HAT-P-16, HAT-P-24, HAT-P-32, HAT-P-34, WASP-12, WASP-16, WASP-18, WASP-19, WASP-26, WASP-31, Gl 436, and Kepler-8), as well as a critical review of previous observations. The low-obliquity (well-aligned) systems are those for which the expected tidal timescale is short, and likewise the high-obliquity (misaligned and retrograde) systems are those for which the expected timescale is long. At face value, this finding indicates that the origin of hot Jupiters involves dynamical interactions like planet-planet interactions or the Kozai effect that tilt their orbits rather than inspiraling due to interaction with a protoplanetary disk. We discuss the status of this hypothesis and the observations that are needed for a more definitive conclusion.

  8. Milky Way mass and potential recovery using tidal streams in a realistic halo

    SciTech Connect (OSTI)

    Bonaca, Ana; Geha, Marla; Küpper, Andreas H. W.; Johnston, Kathryn V.; Diemand, Jürg; Hogg, David W.

    2014-11-01

    We present a new method for determining the Galactic gravitational potential based on forward modeling of tidal stellar streams. We use this method to test the performance of smooth and static analytic potentials in representing realistic dark matter halos, which have substructure and are continually evolving by accretion. Our FAST-FORWARD method uses a Markov Chain Monte Carlo algorithm to compare, in six-dimensional phase space, an 'observed' stream to models created in trial analytic potentials. We analyze a large sample of streams that evolved in the Via Lactea II (VL2) simulation, which represents a realistic Galactic halo potential. The recovered potential parameters are in agreement with the best fit to the global, present-day VL2 potential. However, merely assuming an analytic potential limits the dark matter halo mass measurement to an accuracy of 5%-20%, depending on the choice of analytic parameterization. Collectively, the mass estimates using streams from our sample reach this fundamental limit, but individually they can be highly biased. Individual streams can both under- and overestimate the mass, and the bias is progressively worse for those with smaller perigalacticons, motivating the search for tidal streams at galactocentric distances larger than 70 kpc. We estimate that the assumption of a static and smooth dark matter potential in modeling of the GD-1- and Pal5-like streams introduces an error of up to 50% in the Milky Way mass estimates.

  9. Ecology of Juvenile Salmon in Shallow Tidal Freshwater Habitats of the Lower Columbia River, 2007–2010

    SciTech Connect (OSTI)

    Johnson, Gary E.; Storch, Adam; Skalski, J. R.; Bryson, Amanda J.; Mallette, Christine; Borde, Amy B.; Van Dyke, E.; Sobocinski, Kathryn L.; Sather, Nichole K.; Teel, David; Dawley, Earl M.; Ploskey, Gene R.; Jones, Tucker A.; Zimmerman, Shon A.; Kuligowski, D. R.

    2011-03-01

    The TFM study was designed to investigate the ecology and early life history of juvenile salmonids within shallow (<5 m) tidal freshwater habitats of the LCRE. We started collecting field data in June 2007. Since then, monthly sampling has occurred in the vicinity of the Sandy River delta (rkm 192–208) and at other sites and times in lower river reaches of tidal freshwater (rkm 110 to 141). This report provides a comprehensive synthesis of data covering the field period from June 2007 through April 2010.

  10. An unstructured C-grid based method for 3-D global ocean dynamics: Free-surface formulations and tidal test cases

    E-Print Network [OSTI]

    Peltier, W. Richard

    and tidal test cases G.R. Stuhne *, W.R. Peltier Department of Physics, University of Toronto, 60 St. George numerical framework based on an energy-con- serving Arakawa C-grid discretization could be applied to ocean models. Tidal simulations are much more manageable that full-fledged OGCM climate simulations, being

  11. Using tidally induced water pressure changes to measure in-situ permeability: a1 comparison with long-term pumping tests2

    E-Print Network [OSTI]

    Brodsky, Emily

    Using tidally induced water pressure changes to measure in-situ permeability: a1 comparison of California, Santa Cruz, United States6 (2) University of Guelph, G360 Centre for Applied Groundwater Research KEY POINTS13 Earth tidal responses yield hydraulic properties consistent with pumping tests14 Scale

  12. Radar Remote Sensing Estimates of Waves and Wave Forcing at a Tidal Inlet GUILLERMO M. DAZ MNDEZ AND MERRICK C. HALLER

    E-Print Network [OSTI]

    Haller, Merrick

    Radar Remote Sensing Estimates of Waves and Wave Forcing at a Tidal Inlet GUILLERMO M. DÍAZ MÉNDEZ transformation through a tidal inlet is investigated with radar remote sensing. The frequency of wave breaking-wave conditions, in good agreement (R 5 0.95) with observations. 1. Introduction Remote sensing technology offers

  13. Stratigraphy, pollen history and geochronology of tidal marshes in a Gulf of Maine estuarine system: Climatic and relative sea level impacts

    E-Print Network [OSTI]

    New Hampshire, University of

    Stratigraphy, pollen history and geochronology of tidal marshes in a Gulf of Maine estuarine system stratigraphy pollen accretion relative sea level climate effects Sedimentologic and stratigraphic. The results of this study indicate that the sedimentology and stratigraphy of moderate-size tidal marshes

  14. Sandia Energy - Marine Hydrokinetics Technology: Reference Model...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Offshore Wind High-Resolution Computational Algorithms for Simulating Offshore Wind Farms Innovative Offshore Vertical-Axis Wind Turbine Rotors Offshore Wind RD&D:...

  15. Marine and Hydrokinetic (MHK) Databases and Systems

    SciTech Connect (OSTI)

    2015-01-01

    The online information resources included in this fact sheet were developed with support from the U.S. Department of Energy, and are designed to provide the public access to information pertaining to MHK technologies, projects, and research.

  16. Sandia Energy - Marine Hydrokinetics Technology: Technology Developmen...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and currenttidal power devices. Areas of focus will be on coatings, composites, and molding processes. System Reliability and Survivability Similar to other early stage...

  17. Marine and Hydrokinetic Technology (MHK) Instrumentation, Measurement...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    and Computer Modeling Workshop The workshop brought together over 60 experts in marine energy technologies to disseminate technical information to the marine energy...

  18. Water Power Program: Marine and Hydrokinetic Technologies

    Office of Energy Efficiency and Renewable Energy (EERE)

    Pamphlet that describes the Office of EERE's Water Power Program in fiscal year 2009, including the fiscal year 2009 funding opportunities, the Small Business Innovation Research and Small Business Technology Transfer Programs, the U.S. hydrodynamic testing facilities, and the fiscal year 2008 Advanced Water Projects awards.

  19. Marine and Hydrokinetic Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas:Montezuma,Information MHKMHK5TransportManitouChangeMarc

  20. Marine and Hydrokinetic | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas:Montezuma,Information MHKMHK5TransportManitouChangeMarcMarine andMarine and