National Library of Energy BETA

Sample records for flow power conversion

  1. Power conversion apparatus and method

    DOE Patents [OSTI]

    Su, Gui-Jia (Knoxville, TN)

    2012-02-07

    A power conversion apparatus includes an interfacing circuit that enables a current source inverter to operate from a voltage energy storage device (voltage source), such as a battery, ultracapacitor or fuel cell. The interfacing circuit, also referred to as a voltage-to-current converter, transforms the voltage source into a current source that feeds a DC current to a current source inverter. The voltage-to-current converter also provides means for controlling and maintaining a constant DC bus current that supplies the current source inverter. The voltage-to-current converter also enables the current source inverter to charge the voltage energy storage device, such as during dynamic braking of a hybrid electric vehicle, without the need of reversing the direction of the DC bus current.

  2. Interdigitated photovoltaic power conversion device

    DOE Patents [OSTI]

    Ward, James Scott (Englewood, CO); Wanlass, Mark Woodbury (Golden, CO); Gessert, Timothy Arthur (Conifer, CO)

    1999-01-01

    A photovoltaic power conversion device has a top surface adapted to receive impinging radiation. The device includes at least two adjacent, serially connected cells. Each cell includes a semi-insulating substrate and a lateral conductivity layer of a first doped electrical conductivity disposed on the substrate. A base layer is disposed on the lateral conductivity layer and has the same electrical charge conductivity thereof. An emitter layer of a second doped electrical conductivity of opposite electrical charge is disposed on the base layer and forms a p-n junction therebetween. A plurality of spaced channels are formed in the emitter and base layers to expose the lateral conductivity layer at the bottoms thereof. A front contact grid is positioned on the top surface of the emitter layer of each cell. A first current collector is positioned along one outside edge of at least one first cell. A back contact grid is positioned in the channels at the top surface of the device for engagement with the lateral conductivity layer. A second current collector is positioned along at least one outside edge of at least one oppositely disposed second cell. Finally, an interdigitation mechanism is provided for serially connecting the front contact grid of one cell to the back contact grid of an adjacent cell at the top surface of the device.

  3. Interdigitated photovoltaic power conversion device

    DOE Patents [OSTI]

    Ward, J.S.; Wanlass, M.W.; Gessert, T.A.

    1999-04-27

    A photovoltaic power conversion device has a top surface adapted to receive impinging radiation. The device includes at least two adjacent, serially connected cells. Each cell includes a semi-insulating substrate and a lateral conductivity layer of a first doped electrical conductivity disposed on the substrate. A base layer is disposed on the lateral conductivity layer and has the same electrical charge conductivity thereof. An emitter layer of a second doped electrical conductivity of opposite electrical charge is disposed on the base layer and forms a p-n junction therebetween. A plurality of spaced channels are formed in the emitter and base layers to expose the lateral conductivity layer at the bottoms thereof. A front contact grid is positioned on the top surface of the emitter layer of each cell. A first current collector is positioned along one outside edge of at least one first cell. A back contact grid is positioned in the channels at the top surface of the device for engagement with the lateral conductivity layer. A second current collector is positioned along at least one outside edge of at least one oppositely disposed second cell. Finally, an interdigitation mechanism is provided for serially connecting the front contact grid of one cell to the back contact grid of an adjacent cell at the top surface of the device. 15 figs.

  4. Radio frequency dc-dc power conversion

    E-Print Network [OSTI]

    Rivas, Juan, 1976-

    2007-01-01

    THIS THESIS addresses the development of system architectures and circuit topologies for dc-dc power conversion at very high frequencies. The systems architectures that are developed are structured to overcome limitations ...

  5. Electrical power conversion is essential for improving

    E-Print Network [OSTI]

    Langendoen, Koen

    Electrical power conversion is essential for improving energy efficiency and harvesting renewable energy. Diploma Master of Science Embedded Systems Credits 120 ECTS, 24 months Starts in September universities of technology in the Netherlands - Delft University of Technology, Eindhoven University

  6. ENERGY SERIES "Emerging High Power Conversion Technologies"

    E-Print Network [OSTI]

    Bergman, Keren

    SEMINAR: ENERGY SERIES "Emerging High Power Conversion Technologies" Dujic Drazen Professor, Power of embedded renewable energy sources. Whatever the renewable source of the prime energy is (wind, solar, hydro, storage or use. This is where power electronics come into a play, as key enabling technology for flexible

  7. Project Profile: Brayton Solar Power Conversion System | Department...

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

    Solar Power Conversion System Project Profile: Brayton Solar Power Conversion System Brayton Energy logo Brayton Energy, under the CSP R&D FOA, is looking to demonstrate the...

  8. Power Conversion APEX Interim Report November, 1999

    E-Print Network [OSTI]

    California at Los Angeles, University of

    Efficiency for different steam cycles. 17.2 Close cycle gas turbine: The closed cycle gas turbine has. POWER CONVERSION 17.1 Steam Cycle Different steam cycles have been well developed. A study by EPRI summarized the various advanced steam cycles which maybe available for an advanced coal power plant

  9. Solid-state power conversion handbook

    SciTech Connect (OSTI)

    Tarter, R.E.

    1993-01-01

    This new handbook is the first to be devoted to the field of solid-state power conversion. The material in this book is to be used in engineering practice and is oriented toward application rather than theory. The purpose of the book is to assemble in a single volume all the pertinent and comprehensive information necessary to meet the growing demands placed upon solid-state power conversion equipment. These demands include increased efficiency, improved reliability, higher packaging density, improved performance, and meeting safety and electromagnetic compatibility (EMC) requirements. The material presented includes a thorough analysis of fundamental electrical and magnetic aspects of power conversion plus thermal, protection, and reliability considerations. Attention is focused on semi-conductor and magnetic components and on analysis of various topologies. The handbook is organized into four sections. (1) Chapters 1-3 present the relations of various waveforms, transient components with emphasis on power semiconductors and magnetic components. (2) Chapters 4-12 deal with single-level conversion of rectifier circuits, filters, inverters and converters, feedback and stability analysis, and modulators and pulse-forming networks. (3) Chapters 13-16 discuss ancillary topics related to safety, EMC, thermal management, and reliability. (4) Chapters 17-19 cover design and operation of power supplies and systems from a detailed building block standpoint.

  10. Structural power flow measurement

    SciTech Connect (OSTI)

    Falter, K.J.; Keltie, R.F.

    1988-12-01

    Previous investigations of structural power flow through beam-like structures resulted in some unexplained anomalies in the calculated data. In order to develop structural power flow measurement as a viable technique for machine tool design, the causes of these anomalies needed to be found. Once found, techniques for eliminating the errors could be developed. Error sources were found in the experimental apparatus itself as well as in the instrumentation. Although flexural waves are the carriers of power in the experimental apparatus, at some frequencies longitudinal waves were excited which were picked up by the accelerometers and altered power measurements. Errors were found in the phase and gain response of the sensors and amplifiers used for measurement. A transfer function correction technique was employed to compensate for these instrumentation errors.

  11. Electronic power conditioning for dynamic power conversion in high-power space systems 

    E-Print Network [OSTI]

    Hansen, James Michael

    1991-01-01

    power conversion allows for improved methods of power conditioning. A block diagram of one such system that uses dynamic power conversion is shown in Fig. 4. The blocks labeled Energy Source, Primary Heat Rejection, snd User's Load are the same...ELECTRONIC POWER CONDITIONING FOR DYNAMIC POWER CONVERSION IN HIGH ? POWER SPACE SYSTEMS A Thesis by JAMES MICHAEL HANSEN Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements...

  12. Computational study of power conversion and luminous efficiency performance for

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    Computational study of power conversion and luminous efficiency performance for semiconductor, Singapore 639798, Singapore *volkan@stanfordalumni.org Abstract: We present power conversion efficiency (PCE) and luminous efficiency (LE) performance levels of high photometric quality white LEDs integrated with quantum

  13. Inertial confinement fusion reaction chamber and power conversion system study

    SciTech Connect (OSTI)

    Maya, I.; Schultz, K.R.; Battaglia, J.M.; Buksa, J.J.; Creedson, R.L.; Erlandson, O.D.; Levine, H.E.; Roelant, D.F.; Sanchez, H.W.; Schrader, S.A.

    1984-09-01

    GA Technologies has developed a conceptual ICF reactor system based on the Cascade rotating-bed reaction chamber concept. Unique features of the system design include the use of low activation SiC in a reaction chamber constructed of box-shaped tiles held together in compression by prestressing tendons to the vacuum chamber. Circulating Li/sub 2/O granules serve as the tritium breeding and energy transport material, cascading down the sides of the reaction chamber to the power conversion system. The total tritium inventory of the system is 6 kg; tritium recovery is accomplished directly from the granules via the vacuum system. A system for centrifugal throw transport of the hot Li/sub 2/O granules from the reaction chamber to the power conversion system has been developed. A number of issues were evaluated during the course of this study. These include the response of first-layer granules to the intense microexplosion surface heat flux, cost effective fabrication of Li/sub 2/O granules, tritium inventory and recovery issues, the thermodynamics of solids-flow options, vacuum versus helium-medium heat transfer, and the tradeoffs of capital cost versus efficiency for alternate heat exchange and power conversion system option. The resultant design options appear to be economically competitive, safe, and environmentally attractive.

  14. Effect of electron flow on the ordinary-extraordinary mode conversion

    SciTech Connect (OSTI)

    Jia Guozhang; Gao Zhe

    2011-10-15

    Ordinary-extraordinary mode conversion in the electron cyclotron frequency range is revisited in the presence of a flowing electron component. The analytical expressions of optimal parallel refraction index and conversion efficiency are obtained from a one-dimensional cold plasma model. The presence of flowing electrons leads to an outward shift of the conversion layer and therefore increases the optimal value of parallel refraction index. If this effect is not considered, the efficiency of mode conversion degenerates. In typical tokamak plasmas, this degeneration is about a few percentages, which may induce the reflection of several tens of kilowatts of power from the cutoff layer when injecting megawatts of ECRF power into fusion plasma.

  15. Power Control and Optimization of Photovoltaic and Wind Energy Conversion Systems /

    E-Print Network [OSTI]

    Ghaffari, Azad

    2013-01-01

    Power Optimization and Control in Wind Energy Conversion Systemspower point tracking in wind energy conversion systems,”power point tracking of wind energy conversion systems based

  16. Conversion Tower for Dispatchable Solar Power: High-Efficiency Solar-Electric Conversion Power Tower

    SciTech Connect (OSTI)

    2012-01-11

    HEATS Project: Abengoa Solar is developing a high-efficiency solar-electric conversion tower to enable low-cost, fully dispatchable solar energy generation. Abengoa’s conversion tower utilizes new system architecture and a two-phase thermal energy storage media with an efficient supercritical carbon dioxide (CO2) power cycle. The company is using a high-temperature heat-transfer fluid with a phase change in between its hot and cold operating temperature. The fluid serves as a heat storage material and is cheaper and more efficient than conventional heat-storage materials, like molten salt. It also allows the use of a high heat flux solar receiver, advanced high thermal energy density storage, and more efficient power cycles.

  17. Automotive Waste Heat Conversion to Electric Power using Skutterudites...

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

    Electric Power using Skutterudites, TAGS, PbTe and Bi2Te3 Automotive Waste Heat Conversion to Electric Power using Skutterudites, TAGS, PbTe and Bi2Te3 Presentation given at DEER...

  18. Fabrication and testing of an infrared spectral control component for thermophotovoltaic power conversion applications

    E-Print Network [OSTI]

    O'Sullivan, Francis M. (Francis Martin), 1980-

    2004-01-01

    Thermophotovoltaic (TPV) power conversion is the direct conversion of thermal radiation to electricity. Conceptually, TPV power conversion is a very elegant means of energy conversion. A thermal source emits a radiative ...

  19. Power conversion architecture for grid interface at high switching frequency

    E-Print Network [OSTI]

    Lim, Seungbum

    This paper presents a new power conversion architecture for single-phase grid interface. The proposed architecture is suitable for realizing miniaturized ac-dc converters operating at high frequencies (HF, above 3 MHz) and ...

  20. Opportunities and challenges in Very High Frequency power conversion

    E-Print Network [OSTI]

    Perreault, David J.

    This paper explores opportunities and challenges in power conversion in the VHF frequency range of 30-300 MHz. The scaling of magnetic component size with frequency is investigated, and it is shown that substantial ...

  1. Control strategies for supercritical carbon dioxide power conversion systems

    E-Print Network [OSTI]

    Carstens, Nathan, 1978-

    2007-01-01

    The supercritical carbon dioxide (S-C02) recompression cycle is a promising advanced power conversion cycle which couples well to numerous advanced nuclear reactor designs. This thesis investigates the dynamic simulation ...

  2. Primus Power's Flow Battery Powered by $11 Million in Private...

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

    Primus Power's Flow Battery Powered by 11 Million in Private Investment Primus Power's Flow Battery Powered by 11 Million in Private Investment June 14, 2011 - 10:00am Addthis...

  3. Microturbine Power Conversion Technology Review, April 2003

    Broader source: Energy.gov [DOE]

    A technology review to assess the market for power electronic converters to connect microturbines to the electric grid or local loads.

  4. gtp_flow_power_estimator.xlsx

    Broader source: Energy.gov [DOE]

    This simple spreadsheet model estimates either the flow rate required to produce a specified level of power output, or the power output that can be produced from a specified flow rate.

  5. 10.1117/2.1201108.003807 Solar power conversion using

    E-Print Network [OSTI]

    that, but with additional complexity and cost. Semiconductor solar cells also require costly refined10.1117/2.1201108.003807 Solar power conversion using diodes coupled to antennas Garret Moddel, Zixu Zhu, and Sachit Grover In the developing technology of rectenna solar cells, light is received

  6. SPS energy conversion and power management workshop. Final report

    SciTech Connect (OSTI)

    Not Available

    1980-06-01

    In 1977 a four year study, the concept Development and Evaluation Program, was initiated by the US Department of Energy and the National Aeronautics and Space Administration. As part of this program, a series of peer reviews were carried out within the technical community to allow available information on SPS to be sifted, examined and, if need be, challenged. The SPS Energy Conversion and Power Management Workshop, held in Huntsville, Alabama, February 5 to 7, 1980, was one of these reviews. The results of studies in this particular field were presented to an audience of carefully selected scientists and engineers. This first report summarizes the results of that peer review. It is not intended to be an exhaustive treatment of the subject. Rather, it is designed to look at the SPS energy conversion and power management options in breadth, not depth, to try to foresee any troublesome and/or potentially unresolvable problems and to identify the most promising areas for future research and development. Topics include photovoltaic conversion, solar thermal conversion, and electric power distribution processing and power management. (WHK)

  7. Effect of Electro-Osmotic Flow on Energy Conversion on Superhydrophobic Surfaces

    E-Print Network [OSTI]

    Seshadri, Gowrishankar

    2013-01-01

    It has been suggested that superhydrophobic surfaces, due to the presence of a no-shear zone, can greatly enhance transport of surface charges, leading to a considerable increase in the streaming potential. This could find potential use in micro-energy harvesting devices. In this paper, we show using analytical and numerical methods, that when a streaming potential is generated in such superhydrophobic geometries, the reverse electro-osmotic flow and hence current generated by this, is significant. A decrease in streaming potential compared to what was earlier predicted is expected. We also show that, due to the electro-osmotic streaming-current, a saturation in both the power extracted and efficiency of energy conversion is achieved in such systems for large values of the free surface charge densities. Nevertheless, under realistic conditions, such microstructured devices with superhydrophobic surfaces have the potential to even reach energy conversion efficiencies only achieved in nanostructured devices so ...

  8. On the model discriminating power of mu to e conversion in nuclei...

    Office of Scientific and Technical Information (OSTI)

    On the model discriminating power of mu to e conversion in nuclei Citation Details In-Document Search Title: On the model discriminating power of mu to e conversion in nuclei ...

  9. On the model discriminating power of mu to e conversion in nuclei...

    Office of Scientific and Technical Information (OSTI)

    On the model discriminating power of mu to e conversion in nuclei Citation Details In-Document Search Title: On the model discriminating power of mu to e conversion in nuclei...

  10. Power conversion system design for supercritical carbon dioxide cooled indirect cycle nuclear reactors

    E-Print Network [OSTI]

    Gibbs, Jonathan Paul

    2008-01-01

    The supercritical carbon dioxide (S-CO?) cycle is a promising advanced power conversion cycle which couples nicely to many Generation IV nuclear reactors. This work investigates the power conversion system design and ...

  11. Application of Annular Linear Induction Pumps Technology for Waste Heat Rejection and Power Conversion

    SciTech Connect (OSTI)

    Adkins, Harold E.

    2005-03-16

    The U.S.-sponsored Jupiter Icy Moons Orbiter (JIMO) program will require a light weight, efficient, and reliable power generation system capable of a 20+ year lifespan. This requirement has renewed interest in orbiter technological development. Sub-components of the orbiter system are the primary and secondary power conversion/heat rejection systems for both the proposed nuclear reactors and Brayton cycle heat engines. Brayton-cycle conversion technology has been identified as an excellent candidate for nuclear electric propulsion (NEP) power conversion systems. The conversion/rejection systems for these components typically utilize pumped molten metal as the heat transfer medium. Electromagnetic (EM) Annular Linear Induction Pumps (ALIPs) are ideal for this purpose as they can operate at moderate to high efficiency, at elevated temperature, do not involve moving parts (solid-state; long life), and require no bearings or seals. A parametric study was performed to develop a suite of ALIP preliminary designs capable of providing specified pressure and mass flow rate ranges for the proposed NaK(78) Brayton-cycle heat rejection loop. A limited study was also performed for the proposed lithium-cooled nuclear reactor heat transport loops; however, the design of these units is still in its infancy. Both studies were conducted by Pacific Northwest National Laboratory (PNNL) with the MHD Systems’ ALIP Design Code. The studies focused on designing ALIPs that displayed reasonably high efficiency and low source voltages as well as low mass and smallest geometric envelope.

  12. 420 IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 23, NO. 1, JANUARY 2008 Multilevel DCDC Power Conversion

    E-Print Network [OSTI]

    Tolbert, Leon M.

    boost converter. Experimental results are provided to confirm the analysis and control concept. Index boost converter to interface the bat- tery and the dc bus, one can use separate batteries to power sep Terms--DC­DC power conversion, multilevel converter, pulsewidth modulation (PWM). I. INTRODUCTION

  13. Optimal Demand Response and Power Flow

    E-Print Network [OSTI]

    Willett, Rebecca

    Optimal Demand Response and Power Flow Steven Low Computing + Math Sciences Electrical Engineering #12;Outline Optimal demand response n With L. Chen, L. Jiang, N. Li Optimal power flow n With S. Bose;Optimal demand response Model Results n Uncorrelated demand: distributed alg n Correlated demand

  14. System for thermal energy storage, space heating and cooling and power conversion

    DOE Patents [OSTI]

    Gruen, Dieter M. (Downers Grove, IL); Fields, Paul R. (Chicago, IL)

    1981-04-21

    An integrated system for storing thermal energy, for space heating and cong and for power conversion is described which utilizes the reversible thermal decomposition characteristics of two hydrides having different decomposition pressures at the same temperature for energy storage and space conditioning and the expansion of high-pressure hydrogen for power conversion. The system consists of a plurality of reaction vessels, at least one containing each of the different hydrides, three loops of circulating heat transfer fluid which can be selectively coupled to the vessels for supplying the heat of decomposition from any appropriate source of thermal energy from the outside ambient environment or from the spaces to be cooled and for removing the heat of reaction to the outside ambient environment or to the spaces to be heated, and a hydrogen loop for directing the flow of hydrogen gas between the vessels. When used for power conversion, at least two vessels contain the same hydride and the hydrogen loop contains an expansion engine. The system is particularly suitable for the utilization of thermal energy supplied by solar collectors and concentrators, but may be used with any source of heat, including a source of low-grade heat.

  15. Hybrid Wind Power Balance Control Strategy using Thermal Power, Hydro Power and Flow Batteries

    E-Print Network [OSTI]

    MacDonald, Mark

    Hybrid Wind Power Balance Control Strategy using Thermal Power, Hydro Power and Flow Batteries the con- trolled use of hybrid flow battery, thermal and hydro power plant system, to support wind power on range of thermal and hydro power plant reaction times. This work suggests that power and energy

  16. A Comparison of Coolant Options for Brayton Power Conversion Heat Rejection Systems

    SciTech Connect (OSTI)

    Siamidis, John [Thermal Energy Conversion Branch, Analex Corporation, 21000 Brookpark Rd., Cleveland, OH, 44135 (United States); Mason, Lee [Thermal Energy Conversion Branch, NASA Glenn Research Center, 21000 Brookpark Rd., Cleveland, OH, 44135 (United States)

    2006-01-20

    This paper describes potential heat rejection design concepts for Brayton power conversion systems. Brayton conversion systems are currently under study by NASA for Nuclear Electric Propulsion (NEP) and surface power applications. The Brayton Heat Rejection Subsystem (HRS) must dissipate waste heat generated by the power conversion system due to inefficiencies in the thermal-to-electric conversion process. Sodium potassium (NaK) and H2O are two coolant working fluids that have been investigated in the design of a pumped loop and heat pipe space HRS. In general NaK systems are high temperature (300 to 1000 K) low pressure systems, and H2O systems are low temperature (300 to 600 K) high pressure systems. NaK is an alkali metal with health and safety hazards that require special handling procedures. On the other hand, H2O is a common fluid, with no health hazards and no special handling procedures. This paper compares NaK and H2O for the HRS pumped loop coolant working fluid. A detailed excel analytical model, HRS{sub O}pt, was developed to evaluate the various HRS design parameters. It is capable of analyzing NaK or H2O coolant, parallel or series flow configurations, and numerous combinations of other key parameters (heat pipe spacing, diameter and radial flux, radiator facesheet thickness, fluid duct system pressure drop, system rejected power, etc.) of the HRS. This paper compares NaK against water for the HRS coolant working fluid with respect to the relative mass, performance, design and implementation issues between the two fluids.

  17. Global energy conversion rate from geostrophic flows into internal lee waves in the deep ocean

    E-Print Network [OSTI]

    Nikurashin, Maxim

    A global estimate of the energy conversion rate from geostrophic flows into internal lee waves in the ocean is presented. The estimate is based on a linear theory applied to bottom topography at O(1–10) km scales obtained ...

  18. Advanced power conversion based on the Aerocapacitor{trademark}

    SciTech Connect (OSTI)

    Josephs, L.C.; Gregory, D.; Roark, D. [and others

    1997-10-01

    The authors report here, for the first time, high frequency testing of a new type of electrochemical double layer capacitor (EDLC), based on carbon aerogels: the Aerocapacitor. Carbon aerogels, are a novel type of carbon foam developed by Lawrence Livermore National Laboratory for military applications. The unique properties of carbon aerogels, high surface area (700 m{sup 2}/g), high density (1g/cc), well controlled pore diameter and high material conductivity (25 S/cm) made it an ideal EDLC electrode material. Using carbon aerogel as the electrode material, the authors have developed Aerocapacitors. These new EDLC`s have a frequency response comparable to that of aluminum electrolytic capacitors and are thus ideally suited to power conversion applications.

  19. Solar power conversion efficiency in modulated silicon nanowire photonic Alexei Deinega and Sajeev John

    E-Print Network [OSTI]

    John, Sajeev

    Solar power conversion efficiency in modulated silicon nanowire photonic crystals Alexei Deinega://jap.aip.org/about/rights_and_permissions #12;Solar power conversion efficiency in modulated silicon nanowire photonic crystals Alexei Deinegaa that using only 1 lm of silicon, sculpted in the form of a modulated nanowire photonic crystal, solar power

  20. Soft Magnetic Materials in High-Frequency, High-Power Conversion Applications

    E-Print Network [OSTI]

    McHenry, Michael E.

    and facilitate two-way power conversion.7 Flexible alternating current (AC) Transmission Systems (FACTS) and High Voltage DC (HVDC) technologies aim to improve the effi- ciency of power networks and benefit from highSoft Magnetic Materials in High-Frequency, High-Power Conversion Applications ALEX M. LEARY,1

  1. Closed Brayton cycle power conversion systems for nuclear reactors :

    SciTech Connect (OSTI)

    Wright, Steven A.; Lipinski, Ronald J.; Vernon, Milton E.; Sanchez, Travis

    2006-04-01

    This report describes the results of a Sandia National Laboratories internally funded research program to study the coupling of nuclear reactors to gas dynamic Brayton power conversion systems. The research focused on developing integrated dynamic system models, fabricating a 10-30 kWe closed loop Brayton cycle, and validating these models by operating the Brayton test-loop. The work tasks were performed in three major areas. First, the system equations and dynamic models for reactors and Closed Brayton Cycle (CBC) systems were developed and implemented in SIMULINKTM. Within this effort, both steady state and dynamic system models for all the components (turbines, compressors, reactors, ducting, alternators, heat exchangers, and space based radiators) were developed and assembled into complete systems for gas cooled reactors, liquid metal reactors, and electrically heated simulators. Various control modules that use proportional-integral-differential (PID) feedback loops for the reactor and the power-conversion shaft speed were also developed and implemented. The simulation code is called RPCSIM (Reactor Power and Control Simulator). In the second task an open cycle commercially available Capstone C30 micro-turbine power generator was modified to provide a small inexpensive closed Brayton cycle test loop called the Sandia Brayton test-Loop (SBL-30). The Capstone gas-turbine unit housing was modified to permit the attachment of an electrical heater and a water cooled chiller to form a closed loop. The Capstone turbine, compressor, and alternator were used without modification. The Capstone systems nominal operating point is 1150 K turbine inlet temperature at 96,000 rpm. The annular recuperator and portions of the Capstone control system (inverter) and starter system also were reused. The rotational speed of the turbo-machinery is controlled by adjusting the alternator load by using the electrical grid as the load bank. The SBL-30 test loop was operated at the manufacturers site (Barber-Nichols Inc.) and installed and operated at Sandia. A sufficiently detailed description of the loop is provided in this report along with the design characteristics of the turbo-alternator-compressor set to allow other researchers to compare their results with those measured in the Sandia test-loop. The third task consisted of a validation effort. In this task the test loop was operated and compared with the modeled results to develop a more complete understanding of this electrically heated closed power generation system and to validate the model. The measured and predicted system temperatures and pressures are in good agreement, indicating that the model is a reasonable representation of the test loop. Typical deviations between the model and the hardware results are less than 10%. Additional tests were performed to assess the capability of the Brayton engine to continue to remove decay heat after the reactor/heater is shutdown, to develop safe and effective control strategies, and to access the effectiveness of gas inventory control as an alternative means to provide load following. In one test the heater power was turned off to simulate a rapid reactor shutdown, and the turbomachinery was driven solely by the sensible heat stored in the heater for over 71 minutes without external power input. This is an important safety feature for CBC systems as it means that the closed Brayton loop will keep cooling the reactor without the need for auxiliary power (other than that needed to circulate the waste heat rejection coolant) provided the heat sink is available.

  2. Magnetic Amplifier for Power Flow Control

    SciTech Connect (OSTI)

    2012-02-24

    GENI Project: ORNL is developing an electromagnet-based, amplifier-like device that will allow for complete control over the flow of power within the electric grid. To date, complete control of power flow within the grid has been prohibitively expensive. ORNL’s controller could provide a reliable, cost-effective solution to this problem. The team is combining two types of pre-existing technologies to assist in flow control, culminating in a prototype iron-based magnetic amplifier. Ordinarily, such a device would require expensive superconductive wire, but the magnetic iron core of ORNL’s device could serve as a low-cost alternative that is equally adept at regulating power flow.

  3. 30 DIRECT ENERGY CONVERSION; 20 FOSSIL-FUELED POWER PLANTS; 32...

    Office of Scientific and Technical Information (OSTI)

    Lee, G.T.; Sudhoff, F.A. 30 DIRECT ENERGY CONVERSION; 20 FOSSIL-FUELED POWER PLANTS; 32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; FUEL CELL POWER PLANTS; GAS TURBINE...

  4. Nanoscale Triboelectric-Effect-Enabled Energy Conversion for Sustainably Powering Portable Electronics

    E-Print Network [OSTI]

    Wang, Zhong L.

    Nanoscale Triboelectric-Effect-Enabled Energy Conversion for Sustainably Powering Portable: Harvesting energy from our living environment is an effective approach for sustainable, maintenance-free, and green power source for wireless, portable, or implanted electronics. Mechanical energy scavenging based

  5. Design, Analysis and Optimization of the Power Conversion System for the Modular Pebble Bed Reactor System

    E-Print Network [OSTI]

    Design, Analysis and Optimization of the Power Conversion System for the Modular Pebble Bed Reactor August 31, 2003 Certified by Ronald G. Ballinger Professor of Nuclear Engineering and Materials Science;2 #12;Design, Analysis, and Optimization of the Power Conversion System for the Modular Pebble Bed

  6. On thermoelectric power conversion from heat re-circulating combustion systems F. J. Weinberg

    E-Print Network [OSTI]

    On thermoelectric power conversion from heat re-circulating combustion systems F. J. Weinberg Fax: 4420 7594 5604 Word count: 3750 Diags. equivalent: 1600 5350 #12;On thermoelectric power the absolute maximum efficiency of energy conversion by thermoelectric devices that operate as part of the heat

  7. Advanced power conversion based on the Aerocapacitor{trademark}. Final report

    SciTech Connect (OSTI)

    Roark, D.

    1997-03-05

    This report summarizes work performed under contract No. DE-FC07-94ID13283, {open_quotes}Advanced Power Conversion Based on the Aerocapacitors{trademark}.{close_quotes} Under this contract high power density, high energy density, organic electrolyte Aerocapacitors{trademark} were developed and characterized for power conversion applications. Pilot facilities for manufacturing prototype AA-size Aerocapacitors{trademark} were put in place. The low ESR and good frequency response of these devices show that they are ideal components for high discharge rate and low to moderate frequency (< 10 kHz) applications such as power conversion.

  8. Two-Stage Power Conversion Architecture for an LED Driver Circuit

    E-Print Network [OSTI]

    Perreault, Dave

    Two-Stage Power Conversion Architecture for an LED Driver Circuit Seungbum Lim, John Ranson, David with 0.93 power factor at 8.4 W average power. I. INTRODUCTION LED lighting promises unprecedented efficiency, and high-power-factor LED drivers [1]. A survey of commercial LED drivers illustrates this

  9. Efficient Power Converters for PV Arrays : Scalable Submodule Power Conversion for Utility-Scale Photovoltaics

    SciTech Connect (OSTI)

    2012-02-23

    Solar ADEPT Project: SolarBridge is developing a new power conversion technique to improve the energy output of PV power plants. This new technique is specifically aimed at large plants where many solar panels are connected together. SolarBridge is correcting for the inefficiencies that occur when two solar panels that encounter different amounts of sun are connected together. In most conventional PV system, the weakest panel limits the energy production of the entire system. That’s because all of the energy collected by the PV system feeds into a single collection point where a central inverter then converts it into useable energy for the grid. SolarBridge has found a more efficient and cost-effective way to convert solar energy, correcting these power differences before they reach the grid.

  10. Flow-through biological conversion of lignocellulosic biomass

    DOE Patents [OSTI]

    Herring, Christopher D.; Liu, Chaogang; Bardsley, John

    2014-07-01

    The present invention is directed to a process for biologically converting carbohydrates from lignocellulosic biomass comprising the steps of: suspending lignocellulosic biomass in a flow-through reactor, passing a reaction solution into the reactor, wherein the solution is absorbed into the biomass substrate and at least a portion of the solution migrates through said biomass substrate to a liquid reservoir, recirculating the reaction solution in the liquid reservoir at least once to be absorbed into and migrate through the biomass substrate again. The biological converting of the may involve hydrolyzing cellulose, hemicellulose, or a combination thereof to form oligosaccharides, monomelic sugars, or a combination thereof; fermenting oligosaccharides, monomelic sugars, or a combination thereof to produce ethanol, or a combination thereof. The process can further comprise removing the reaction solution and processing the solution to separate the ethanol produced from non-fermented solids.

  11. Flow reversal power limit for the HFBR

    SciTech Connect (OSTI)

    Cheng, L.Y.; Tichler, P.R.

    1997-01-01

    The High Flux Beam Reactor (HFBR) is a pressurized heavy water moderated and cooled research reactor that began operation at 40 MW. The reactor was subsequently upgraded to 60 MW and operated at that level for several years. The reactor undergoes a buoyancy-driven reversal of flow in the reactor core following certain postulated accidents. Questions which were raised about the afterheat removal capability during the flow reversal transition led to a reactor shutdown and subsequent resumption of operation at a reduced power of 30 MW. An experimental and analytical program to address these questions is described in this report. The experiments were single channel flow reversal tests under a range of conditions. The analytical phase involved simulations of the tests to benchmark the physical models and development of a criterion for dryout. The criterion is then used in simulations of reactor accidents to determine a safe operating power level. It is concluded that the limit on the HFBR operating power with respect to the issue of flow reversal is in excess of 60 MW. Direct use of the experimental results and an understanding of the governing phenomenology supports this conclusion.

  12. Novel, Integrated Reactor / Power Conversion System (LMR-AMTEC)

    SciTech Connect (OSTI)

    Pablo Rubiolo, Principal Investigator

    2003-03-21

    The main features of this project were the development of a long life (up to 10 years) Liquid Metal Reactor (LMR) and a static conversion subsystem comprising an Alkali Metal Thermal-to-Electric (AMTEC) topping cycle and a ThermoElectric (TE) Bottom cycle. Various coupling options of the LMR with the energy conversion subsystem were explored and, base in the performances found in this analysis, an Indirect Coupling (IC) between the LMR and the AMTEC/TE converters with Alkali Metal Boilers (AMB) was chosen as the reference design. The performance model of the fully integrated sodium-and potassium-AMTEC/TE converters shows that a combined conversion efficiency in excess of 30% could be achieved by the plant. (B204)

  13. Development and Analysis of Advanced High-Temperature Technology for Nuclear Heat Transport and Power Conversion

    SciTech Connect (OSTI)

    Per F. Peterson

    2010-03-01

    This project by the Thermal Hydraulics Research Laboratory at U.C. Berkeley Studied advanced high-temperature heat transport and power conversion technology, in support of the Nuclear Hydrogen Initiative and Generation IV.

  14. Design, analysis and optimization of the power conversion system for the Modular Pebble Bed Reactor System

    E-Print Network [OSTI]

    Wang, Chunyun, 1968-

    2003-01-01

    The Modular Pebble Bed Reactor system (MPBR) requires a gas turbine cycle (Brayton cycle) as the power conversion system for it to achieve economic competitiveness as a GenIV nuclear system. The availability of controllable ...

  15. Evaluation of ethane as a power conversion system working fluid for fast reactors

    E-Print Network [OSTI]

    Perez, Jeffrey A

    2008-01-01

    A supercritical ethane working fluid Brayton power conversion system is evaluated as an alternative to carbon dioxide. The HSC® chemical kinetics code was used to study thermal dissociation and chemical interactions for ...

  16. Oil to Coal Conversion of Power and Industrial Facilities in the Dominican Republic 

    E-Print Network [OSTI]

    Causilla, H.; Acosta, J. R.

    1982-01-01

    and economic feasibility of converting power plants and cement plants from oil to coal. The summary results and conclusions are presented and include coal conversion capital costs, cost savings, and program overall schedule. The intent of the authors...

  17. Proc 12th conf. RF Power in Plasmas, Savannah, 1997 Ion-Bernstein Wave Mode Conversion

    E-Print Network [OSTI]

    Jaun, André

    Proc 12th conf. RF Power in Plasmas, Savannah, 1997 Ion-Bernstein Wave Mode Conversion in Hot-Bernstein wave can dramatically affect the power profile and partition among the species. The results obtained very different wavelengths. Where the spa- tial scale of two waves match, the power associated with one

  18. Keeping the Power Flowing | 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 WebQuantityBonneville Power Administration would likeUniverseIMPACTThousand Cubic Feet) SoldDepartment of EnergyPower Flowing

  19. The capacitively coupled converter (Cł) for high power DC-DC conversion 

    E-Print Network [OSTI]

    Khan, Shahriar

    1992-01-01

    THE CAPACITIVELY COUPLED CONVERTER (C3) FOR HIGH POWER DC-DC CONVERSION A Thesis by SHAHRIAR KHAN Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER... OF SCIENCE May 1992 Major Subject: Electrical Engineering THE CAPACITIVELY COUPLED CONVERTER (Cs) FOR HIGH POWER DC-DC CONVERSION A Thesis by SHAHRIAR KHAN Approved as to style and content by: Mehrdad Ehsani (Chair of Committee) Prasad Enjeti...

  20. Advanced, High Power, Next Scale, Wave Energy Conversion Device

    SciTech Connect (OSTI)

    Hart, Philip R.

    2011-09-27

    This presentation from the Water Peer Review highlights one of the program's marine and hyrokinetics device design projects to scale up the current Ocean Power Technology PowerBuoy from 150kW to 500kW.

  1. Circuits and passive components for radio-frequency power conversion

    E-Print Network [OSTI]

    Han, Yehui, Ph. D. Massachusetts Institute of Technology

    2010-01-01

    This thesis focuses on developing technology for high efficiency power converters operating at very high frequencies. The work in the thesis involves two aspects of such converters: rf (radio-frequency) power circuit design ...

  2. Static power conversion techniques for unique energy devices 

    E-Print Network [OSTI]

    Welch, Richard Andrew

    1998-01-01

    Solar power, fuel cells, and supercapacitors are some hics. of the new energy devices that are being used today in various power applications. The first two of these devices are exciting alternative sources of clean energy. The third device...

  3. Advanced, High Power, Next Scale, Wave Energy Conversion Device

    SciTech Connect (OSTI)

    Mekhiche, Mike; Dufera, Hiz; Montagna, Deb

    2012-10-29

    The project conducted under DOE contract DE?EE0002649 is defined as the Advanced, High Power, Next Scale, Wave Energy Converter. The overall project is split into a seven?stage, gated development program. The work conducted under the DOE contract is OPT Stage Gate III work and a portion of Stage Gate IV work of the seven stage product development process. The project effort includes Full Concept Design & Prototype Assembly Testing building on our existing PowerBuoy? technology to deliver a device with much increased power delivery. Scaling?up from 150kW to 500kW power generating capacity required changes in the PowerBuoy design that addressed cost reduction and mass manufacturing by implementing a Design for Manufacturing (DFM) approach. The design changes also focused on reducing PowerBuoy Installation, Operation and Maintenance (IO&M) costs which are essential to reducing the overall cost of energy. In this design, changes to the core PowerBuoy technology were implemented to increase capability and reduce both CAPEX and OPEX costs. OPT conceptually envisaged moving from a floating structure to a seabed structure. The design change from a floating structure to seabed structure would provide the implementation of stroke? unlimited Power Take?Off (PTO) which has a potential to provide significant power delivery improvement and transform the wave energy industry if proven feasible.

  4. Distributed Power Flow Control: Distributed Power Flow Control using Smart Wires for Energy Routing

    SciTech Connect (OSTI)

    2012-04-24

    GENI Project: Smart Wire Grid is developing a solution for controlling power flow within the electric grid to better manage unused and overall transmission capacity. The 300,000 miles of high-voltage transmission line in the U.S. today are congested and inefficient, with only around 50% of all transmission capacity utilized at any given time. Increased consumer demand should be met in part with more efficient and an economical power flow. Smart Wire Grid’s devices clamp onto existing transmission lines and control the flow of power within—much like how internet routers help allocate bandwidth throughout the web. Smart wires could support greater use of renewable energy by providing more consistent control over how that energy is routed within the grid on a real-time basis. This would lessen the concerns surrounding the grid’s inability to effectively store intermittent energy from renewables for later use.

  5. Power Conversion Efficiency Characterization and Optimization for Smartphones

    E-Print Network [OSTI]

    Pedram, Massoud

    waste a significant amount of the battery's stored energy during power con- version from the 3.7V output this energy waste in smartphones is to (i) profile the power consumption of each module under different with a multi-core gi- gahertz processor, gigabytes of high-speed DDR SDRAM, dozens of gigabytes of flash memory

  6. Opportunities and Challenges in Very High Frequency Power Conversion

    E-Print Network [OSTI]

    Perreault, Dave

    in switching frequency directly reduce the energy- storage requirements of power converters, improving achiev transition times. In this paper, we will focus on designs compatible with zero-voltage switching and resonant methods. We present an overview of the design of power electronics at extreme high frequencies

  7. Structural Detuning of Pump Absorption Rate in Doped Fiber for the Enhancement of Power Conversion Efficiency

    E-Print Network [OSTI]

    Park, Namkyoo

    Structural Detuning of Pump Absorption Rate in Doped Fiber for the Enhancement of Power Conversion Doped Fiber Amplifier. With proper adjustments on doping profiles for the reduction of pump absorption rate, it becomes possible to optimize pump evolution map inside the doped fiber to get better power

  8. Power Flow Controller for Renewables: Transformer-less Unified Power Flow Controller for Wind and Solar Power Transmission

    SciTech Connect (OSTI)

    2012-02-08

    GENI Project: MSU is developing a power flow controller to improve the routing of electricity from renewable sources through existing power lines. The fast, innovative, and lightweight circuitry that MSU is incorporating into its controller will eliminate the need for a separate heavy and expensive transformer, as well as the construction of new transmission lines. MSU’s controller is better suited to control power flows from distributed and intermittent wind and solar power systems than traditional transformer-based controllers are, so it will help to integrate more renewable energy into the grid. MSU‘s power flow controller can be installed anywhere in the existing grid to optimize energy transmission and help reduce transmission congestion.

  9. Stirling engine power control and motion conversion mechanism

    DOE Patents [OSTI]

    Marks, David T. (Birmingham, MI)

    1983-01-01

    A motion conversion device for converting between the reciprocating motion of the pistons in a Stirling engine and the rotating motion of its output shaft, and for changing the stroke and phase of the pistons, includes a lever pivoted at one end and having a cam follower at the other end. The piston rod engages the lever intermediate its ends and the cam follower engages a cam keyed to the output shaft. The lever pivot can be moved to change the length of the moment arm defined between the cam follower and the piston rod the change the piston stroke and force exerted on the cam, and the levers can be moved in opposite directions to change the phase between pistons.

  10. A new continuous-flow process for catalytic conversion of glycerol to oxygenated fuel additive: Catalyst screening

    E-Print Network [OSTI]

    Qin, Wensheng

    in acetone/glycerol molar ratio or a decrease in WHSV enhanced the glycerol conversion as expected promoter as the addition of ketals and ethers in gasoline engines improve the octane number, cold flow

  11. Power Conversion Architecture for Grid Interface at High Switching Frequency

    E-Print Network [OSTI]

    Perreault, Dave

    voltage from the voltage of energy buffer capacitor. The boost converter is often selected for PFC circuit output powers). Instead of a boost converter, one alternative for the PFC circuit is a buck converter is suitable for realizing miniaturized ac-dc converters operating at high frequencies (HF, above 3 MHz

  12. Increased Power Generation in a Continuous Flow MFC with

    E-Print Network [OSTI]

    Increased Power Generation in a Continuous Flow MFC with Advective Flow through the Porous Anode, The Pennsylvania State University, University Park, Pennsylvania 16802 The maximum power generated in a single without affecting power generation (16). Pt can be replaced by less expensive alternatives such as Co

  13. Startup Design Features for Supercritical Power Conversion Systems - 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 WebQuantityBonneville Power AdministrationRobust,Field-effect Photovoltaics -7541C.3X-rays Illuminate aStructural BasisResidualInnovation

  14. Sandia Energy » thermo-electric power conversion technology

    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 AdministrationRobust, High-ThroughputUpcoming Release of the University of2013 DomeniciTwo

  15. Power Conversion Apparatus and Method for Hybrid Electric and Electric

    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 mapSpeedingProgram Guidelines This document outlinesPotentialReactorPortal

  16. Definitional mission report: NAPCOR thermal-power-conversion project, Philippines. Export trade information

    SciTech Connect (OSTI)

    Not Available

    1991-11-01

    The National Power Corporation (NAPCOR) of Philippines has requested the Trade and Development Program (TDP) to fund a study to evaluate the technical and economic feasibility of converting its existing oil and coal fired power plants to natural gas. The decision to undertake the study resulted from preliminary information on a large gas find off the coast of Palawan island. However, a second exploration well has come up dry. Now, the conversion of the existing power plants to natural gas seems very questionable. Even if the proven gas reserves prove to be commercially viable, the gas will not be available until 1998 or later for utilization. At that time several of NAPCOR's plants would have aged further, the political and economic situation in Philippines could have altered significantly, possibly improved, private power companies might be able to use the gas more efficiently by building state-of-the-art combined cycle power plants which will make more economic sense than converting existing old boilers to natural gas. In addition, most of the existing power equipment was manufactured by Japanese and/or European firms. It makes sense for NAPCOR to solicit services from these firms if it decides to go ahead with the implementation of the power plant conversion project. The potential for any follow on work for U.S. businesses is minimal to zero in the thermal conversion project. Therefore, at this time, TDP funding for the feasibility would be premature and not recommended.

  17. Distributed Algorithms for Optimal Power Flow Problem

    E-Print Network [OSTI]

    Lam, Albert Y S; Tse, David

    2011-01-01

    Optimal power flow (OPF) is an important problem for power generation and it is in general non-convex. With the employment of renewable energy, it will be desirable if OPF can be solved very efficiently so its solution can be used in real time. With some special network structure, e.g. trees, the problem has been shown to have a zero duality gap and the convex dual problem yields the optimal solution. In this paper, we propose a primal and a dual algorithm to coordinate the smaller subproblems decomposed from the convexified OPF. We can arrange the subproblems to be solved sequentially and cumulatively in a central node or solved in parallel in distributed nodes. We test the algorithms on IEEE radial distribution test feeders, some random tree-structured networks, and the IEEE transmission system benchmarks. Simulation results show that the computation time can be improved dramatically with our algorithms over the centralized approach of solving the problem without decomposition, especially in tree-structured...

  18. Electronic Power Conversion System for an Advanced Mobile Generator Set Leon M. Tolbert1,3

    E-Print Network [OSTI]

    Tolbert, Leon M.

    . The military generator set uses an internal combustion diesel engine to drive a radial-gap permanent magnet. The variable frequency, variable voltage produced by the permanent magnet alternator is diode-rectified to dcElectronic Power Conversion System for an Advanced Mobile Generator Set Leon M. Tolbert1

  19. Lunar electric power systems utilizing the SP-100 reactor coupled to dynamic conversion systems. Final report

    SciTech Connect (OSTI)

    Harty, R.B.; Durand, R.E.

    1993-03-01

    An integration study was performed by Rocketdyne under contract to NASA-LeRC. The study was concerned with coupling an SP-0100 reactor to either a Brayton or Stirling power conversion system. The application was for a surface power system to supply power requirements to a lunar base. A power level of 550 kWe was selected based on the NASA Space Exploration Initiative 90-day study. Reliability studies were initially performed to determine optimum power conversion redundancy. This study resulted in selecting three operating engines and one stand-by unit. Integration design studies indicated that either the Brayton or Stirling power conversion systems could be integrated with the PS-100 reactor. The Stirling system had an integration advantage because of smaller piping size and fewer components. The Stirling engine, however, is more complex and heavier than the Brayton rotating unit, which tends to off-set the Stirling integration advantage. From a performance consideration, the Brayton had a 9 percent mass advantage, and the Stirling had a 50 percent radiator advantage.

  20. Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow

    E-Print Network [OSTI]

    Marchese, Francis

    Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow

  1. Evaluation and Optimization of a Supercritical Carbon Dioxide Power Conversion Cycle for Nuclear Applications

    SciTech Connect (OSTI)

    Edwin A. Harvego; Michael G. McKellar

    2011-05-01

    There have been a number of studies involving the use of gases operating in the supercritical mode for power production and process heat applications. Supercritical carbon dioxide (CO2) is particularly attractive because it is capable of achieving relatively high power conversion cycle efficiencies in the temperature range between 550°C and 750°C. Therefore, it has the potential for use with any type of high-temperature nuclear reactor concept, assuming reactor core outlet temperatures of at least 550°C. The particular power cycle investigated in this paper is a supercritical CO2 Recompression Brayton Cycle. The CO2 Recompression Brayton Cycle can be used as either a direct or indirect power conversion cycle, depending on the reactor type and reactor outlet temperature. The advantage of this cycle when compared to the helium Brayton Cycle is the lower required operating temperature; 550°C versus 850°C. However, the supercritical CO2 Recompression Brayton Cycle requires an operating pressure in the range of 20 MPa, which is considerably higher than the required helium Brayton cycle operating pressure of 8 MPa. This paper presents results of analyses performed using the UniSim process analyses software to evaluate the performance of the supercritical CO2 Brayton Recompression Cycle for different reactor outlet temperatures. The UniSim model assumed a 600 MWt reactor power source, which provides heat to the power cycle at a maximum temperature of between 550°C and 750°C. The UniSim model used realistic component parameters and operating conditions to model the complete power conversion system. CO2 properties were evaluated, and the operating range for the cycle was adjusted to take advantage of the rapidly changing conditions near the critical point. The UniSim model was then optimized to maximize the power cycle thermal efficiency at the different maximum power cycle operating temperatures. The results of the analyses showed that power cycle thermal efficiencies in the range of 40 to 50% can be achieved.

  2. Solution-Processed Organic Solar Cells with Power Conversion Efficiencies of 2.5% using Benzothiadiazole/Imide-Based Acceptors

    E-Print Network [OSTI]

    McGehee, Michael

    Solution-Processed Organic Solar Cells with Power Conversion Efficiencies of 2.5% using achieved 0.1% power-conversion efficiency. KEYWORDS: organic electronics, solar cells, photovoltaic devices significantly different behav- iors in bulk heterojunction (BHJ) solar cells using poly(3-hexylthiophene) (P3HT

  3. Human Factors Aspects of Power System Flow Animation

    E-Print Network [OSTI]

    Human Factors Aspects of Power System Flow Animation Douglas A. Wiegmann, Gavin R. Essenberg experimental results associated with human factors aspects of using animation to display electric power system. Index Terms--Power System Operations and Planning, Power System Visualization, Animation, Human Factors

  4. Fast Power Flow Methods 1.0 Introduction

    E-Print Network [OSTI]

    McCalley, James D.

    1 Fast Power Flow Methods 1.0 Introduction What we have learned so far is the so-called "full that with a NR. But NR is slow! Often, the problem is not so "tough," and in that case, the so-called fast is fast and robust, it is not very accurate. Solving the power flow equations can be computationally

  5. Biostirling({trademark}): A small biomass power conversion system using an advanced stirling engine

    SciTech Connect (OSTI)

    Johansson, L.; Ziph, B.; McKeough, W.; Houtman, W.

    1996-12-31

    Over the past decade the need for small power conversion systems to serve rural and/or remote needs has increased dramatically. The requirements for systems <100 kW are very similar, whether the need is defined as {open_quotes}rural electrification{close_quotes} in developed countries, or as {open_quotes}village power{close_quotes} in developing countries. The availability of biomass fuel resources to serve such systems is not in doubt, be they agricultural, forestry, animal or urban wastes. The main inhibiting factor has been the absence of a biomass power conversion system characterized by: reliability, cost effectiveness, low pollution, and ease of maintenance. Stirling Thermal Motors of Ann Arbor, Michigan, is recognized as the leader worldwide in the development and application of Stirling engine technology. It is currently demonstrating a {open_quotes}BioStirling({trademark}){close_quotes} Power Conversion System which combines its unique STM4-120 engine rated at 25 kW with a proven commercial gasifier. The BioStirling({trademark}) proof-of-concept demonstration is funded by DOE`s National Renewable Energy Laboratory and is to be completed in late 1996, with field demonstrations in 1997 and commercial availability 1998.

  6. BiogeographyBiogeography--Based OptimizationBased Optimization of Power Flowof Power Flow

    E-Print Network [OSTI]

    Simon, Dan

    and phase angle vectors: 60 unknowns #12;7 Power Flow ProblemPower Flow Problem Cost Function = Power / Voltage Mismatch (Ideally = 0) ( ) ( ) ( ){ }2 2 2 min i Q i V i i Gen i PQ i PV P Q V + + V, V, V = - = - - = + - = + - a b #12;12 Simulation GA and BBO Performance ( )cost cost individual, generation, trial= ind trial gen

  7. Highly-Efficient Thermoelectronic Conversion of Solar Energy and Heat into Electric Power

    E-Print Network [OSTI]

    Meir, S; Geballe, T H; Mannhart, J

    2013-01-01

    Electric power may, in principle, be generated in a highly efficient manner from heat created by focused solar irradiation, chemical combustion, or nuclear decay by means of thermionic energy conversion. As the conversion efficiency of the thermionic process tends to be degraded by electron space charges, the efficiencies of thermionic generators have amounted to only a fraction of those fundamentally possible. We show that this space-charge problem can be resolved by shaping the electric potential distribution of the converter such that the static electron space-charge clouds are transformed into an output current. Although the technical development of practical generators will require further substantial efforts, we conclude that a highly efficient transformation of heat to electric power may well be achieved.

  8. DC Optimal Power Flow: Uniqueness and Chee Wei Tan

    E-Print Network [OSTI]

    Tan, Chee Wei

    the minimization of power transmission loss in DC-OPF and char- acterize the uniqueness of its solutions. This hasDC Optimal Power Flow: Uniqueness and Algorithms Chee Wei TanÝ , Desmond W. H. CaiŁ and Xin LouÝ Ý and transmission loss in a power net- work subject to physical constraints governed by Kirchhoff's and Ohm's law [1

  9. Power Control and Optimization of Photovoltaic and Wind Energy Conversion Systems /

    E-Print Network [OSTI]

    Ghaffari, Azad

    2013-01-01

    77 5.2 Wind Energy Conversion System . . . . .Optimization and Control in Wind Energy Conversion SystemsAC matrix con- verter for wind energy conversion system,” in

  10. Power conversion efficiency, electrode separation, and overpotential in the ferricyanide/ferrocyanide thermogalvanic cell

    SciTech Connect (OSTI)

    Mua, Y.; Quickenden, T.I. [Univ. of Western Australia, Nedlands, Western Australia (Australia). Dept. of Chemistry

    1996-08-01

    Thermogalvanic cells are electrochemical cells in which thermal energy is converted to electrical energy by maintaining the two (usually identical) electrodes at different temperatures. The effect of electrode separation on the power conversion efficiency of a ferricyanide/ferrocyanide thermogalvanic cell containing platinum electrodes was studied at electrode separations up to 150 cm, using the ``cold-above-hot`` electrode configuration. The open-circuit potential difference is almost independent of electrode separation, but the short-circuit current density falls continuously with increasing electrode separation, while the power conversion efficiency increases asymptotically to a plateau value of ca. 0.04% at a separation near 150 cm. This corresponds to an efficiency of ca. 0.6% relative to that of a Carnot engine operating between the temperatures of 293.1 and 313.1 K used in the present study. A separation of 10 cm provides efficiencies which are ca. 83% of the plateau value and is a convenient separation to use if minimal cell volume is required. The power conversion efficiency of the cell was largely limited by ohmic overpotential. Measured exchange current densities showed that activation overpotential has negligible effect on cell current. Mass transport does not limit the cell current because of the beneficial convection caused by the ``cold-above-hot`` electrode configuration.

  11. Contingency Analysis of Power System using Power Flow

    E-Print Network [OSTI]

    Lavaei, Javad

    and to minimize customer outages. i II. Motivation The security of a power grid into account. The other common causes of faults are weather related.0 ­ Typical Causes of Faults iii Source: Richard Brown. Electric Power Distribution

  12. Survey and conceptual flow sheets for coal conversion plant handling-preparation and ash/slag removal operations

    SciTech Connect (OSTI)

    Zapp, F.C.; Thomas, O.W.; Silverman, M.D.; Dyslin, D.A.; Holmes, J.M.

    1980-03-01

    This study was undertaken at the request of the Fossil Fuel Processing Division of the Department of Energy. The report includes a compilation of conceptual flow sheets, including major equipment lists, and the results of an availability survey of potential suppliers of equipment associated with the coal and ash/slag operations that will be required by future large coal conversion plant complexes. Conversion plant flow sheet operations and related equipment requirements were based on two representative bituminous coals - Pittsburgh and Kentucky No. 9 - and on nine coal conversion processes. It appears that almost all coal handling and preparation and ash/slag removal equipment covered by this survey, with the exception of some coal comminution equipment, either is on hand or can readily be fabricated to meet coal conversion plant capacity requirements of up to 50,000 short tons per day. Equipment capable of handling even larger capacities can be developed. This approach appears to be unjustified, however, because in many cases a reasonable or optimum number of trains of equipment must be considered when designing a conversion plant complex. The actual number of trains of equipment selected will be influenced by the total requied capacity of the complex, the minimum on-line capacity that can be tolerated in case of equipment failure, reliability of specific equipment types, and the number of reactors and related feed injection stations needed for the specific conversion process.

  13. Selected papers from the 9th International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications (PowerMEMS 2009)

    E-Print Network [OSTI]

    Rubloff, Gary W.

    and Nanotechnology for Power Generation and Energy Conversion Applications (PowerMEMS 2009) Guest Editors Reza selected from the 9th International Workshop on Micro and Nanotechnology for Power Generation and EnergySelected papers from the 9th International Workshop on Micro and Nanotechnology for Power

  14. Computing an operating parameter of a unified power flow controller

    DOE Patents [OSTI]

    Wilson, David G; Robinett, III, Rush D

    2015-01-06

    A Unified Power Flow Controller described herein comprises a sensor that outputs at least one sensed condition, a processor that receives the at least one sensed condition, a memory that comprises control logic that is executable by the processor; and power electronics that comprise power storage, wherein the processor causes the power electronics to selectively cause the power storage to act as one of a power generator or a load based at least in part upon the at least one sensed condition output by the sensor and the control logic, and wherein at least one operating parameter of the power electronics is designed to facilitate maximal transmittal of electrical power generated at a variable power generation system to a grid system while meeting power constraints set forth by the electrical power grid.

  15. Does the Poynting vector always represent electromagnetic power flow?

    E-Print Network [OSTI]

    Changbiao Wang

    2015-07-07

    Poynting vector as electromagnetic power flow has prevailed over one hundred years in the community. However in this paper, it is shown from Maxwell equations that the Poynting vector may not represent the electromagnetic power flow for a plane wave in a non-dispersive, lossless, non-conducting, anisotropic uniform medium; this important conclusion revises the conventional understanding of Poynting vector. It is also shown that this conclusion is clearly supported by Fermat's principle and special theory of relativity.

  16. Does the Poynting vector always represent electromagnetic power flow?

    E-Print Network [OSTI]

    Wang, Changbiao

    2015-01-01

    Poynting vector as electromagnetic power flow has prevailed over one hundred years in the community. However in this paper, it is shown from Maxwell equations that the Poynting vector may not represent the electromagnetic power flow for a plane wave in a non-dispersive, lossless, non-conducting, anisotropic uniform medium; this important conclusion revises the conventional understanding of Poynting vector. It is also shown that this conclusion is clearly supported by Fermat's principle and special theory of relativity.

  17. Lithium Mass Flow Control for High Power Lorentz Force Accelerators

    E-Print Network [OSTI]

    Lithium Mass Flow Control for High Power Lorentz Force Accelerators Andrea D. Kodys1 , Gregory Laboratory, Pasadena, CA 91109 (609).258.5220, choueiri@princeton.edu Abstract. A lithium feeding system has been developed to measure and control propellant flow for 30-200 kW Lithium Lorentz Force Accelerators

  18. Global Optimization of Optimal Power Flow

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    Multi-Period OPF ­ `Smart Grid' · Transmission short falls due to ­ Fluctuating demands. ­ Integrating/03/2013 2 AC-OPF definition · Given: Topology of the power grid: generators, loads, power lines. · Objective: ­ Find operating points for generators, (PG,QG) ­ Minimizing cost of generation ­ f(PG) · Satisfy

  19. Plant Design and Cost Estimation of a Natural Circulation Lead-Bismuth Reactor with Helium Power Conversion Cycle

    E-Print Network [OSTI]

    Kim, D.

    The analysis of an indirect helium power conversion system with lead-bismuth natural circulation primary system has been performed. The work of this report is focused on 1) identifying the allowable design region for the ...

  20. Power Electronic Topologies with High Density Power Conversion and Galvanic Isolation for Utility Interface 

    E-Print Network [OSTI]

    Krishnamoorthy, Harish Sarma

    2015-01-26

    the transformers, inductors and DC electrolytic capacitors. Instead of using a line frequency transformer to interface any power electronic system with the utility grid directly, it is possible to use a power converter to transform the line frequency AC into a...

  1. Transaction Based Power Flow Analysis For Transmission Utilization Allocation

    E-Print Network [OSTI]

    electricity market at the ex ante phase; (ii) MW generations are decided by bilateral contracts and other contributions of individual generators to loads and flows upon the so-called proportional sharing principle the electric power industry moves into an era of supply competition and consumer choice, the power system

  2. Brayton power conversion system parametric design modelling for nuclear electric propulsion. Final report

    SciTech Connect (OSTI)

    Ashe, T.L.; Otting, W.D.

    1993-11-01

    The parametrically based closed Brayton cycle (CBC) computer design model was developed for inclusion into the NASA LeRC overall Nuclear Electric Propulsion (NEP) end-to-end systems model. The code is intended to provide greater depth to the NEP system modeling which is required to more accurately predict the impact of specific technology on system performance. The CBC model is parametrically based to allow for conducting detailed optimization studies and to provide for easy integration into an overall optimizer driver routine. The power conversion model includes the modeling of the turbines, alternators, compressors, ducting, and heat exchangers (hot-side heat exchanger and recuperator). The code predicts performance to significant detail. The system characteristics determined include estimates of mass, efficiency, and the characteristic dimensions of the major power conversion system components. These characteristics are parametrically modeled as a function of input parameters such as the aerodynamic configuration (axial or radial), turbine inlet temperature, cycle temperature ratio, power level, lifetime, materials, and redundancy.

  3. Kinematic Stirling engine as an energy conversion subsystem for paraboloidal dish solar thermal power plants

    SciTech Connect (OSTI)

    Bowyer, J.M.

    1984-04-15

    The potential of a suitably designed and economically manufactured Stirling engine as the energy conversion subsystem of a paraboloidal dish-Stirling solar thermal power module has been estimated. Results obtained by elementary cycle analyses have been shown to match quite well the performance characteristics of an advanced kinematic Stirling engine, the United Stirling P-40, as established by current prototypes of the engine and by a more sophisticated analytic model of its advanced derivative. In addition to performance, brief consideration has been given to other Stirling engine criteria such as durability, reliability, and serviceability. Production costs have not been considered here.

  4. Free Flow Power 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 ECoopButtePowerEdistoWhiskeyFootprint Ventures JumpIndiana:BuildingPower Corporation

  5. The desire to achieve both high power density and high power conversion efficiency leads to several required features of a first wall and blanket concept. Achieving high

    E-Print Network [OSTI]

    California at Los Angeles, University of

    required features of a first wall and blanket concept. Achieving high power density means that the coolant wall and blanket design, tritium breeding, activation and waste, power conversion, first wall thermo First wall heat flux 2 MW/m2 Neutron wall load 10 MW/m2 Tritium Breeding Ratio (local 2D) 1.37 Power

  6. Development of a concentrating solar power system using fluidized-bed technology for thermal energy conversion and solid particles for thermal energy storage

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

    Ma, Z.; Mehos, M.; Glatzmaier, G.; Sakadjian, B. B.

    2015-05-01

    Concentrating solar power (CSP) is an effective way to convert solar energy into electricity with an economic energy-storage capability for grid-scale, dispatchable renewable power generation. However, CSP plants need to reduce costs to be competitive with other power generation methods. Two ways to reduce CSP cost are to increase solar-to-electric efficiency by supporting a high-efficiency power conversion system, and to use low-cost materials in the system. The current nitrate-based molten-salt systems have limited potential for cost reduction and improved power-conversion efficiency with high operating temperatures. Even with significant improvements in operating performance, these systems face challenges in satisfying the costmore »and performance targets. This paper introduces a novel CSP system with high-temperature capability that can be integrated into a high-efficiency CSP plant and that meets the low-cost, high-performance CSP targets. Unlike a conventional salt-based CSP plant, this design uses gas/solid, two-phase flow as the heat-transfer fluid (HTF); separated solid particles as storage media; and stable, inexpensive materials for the high-temperature receiver and energy storage containment. We highlight the economic and performance benefits of this innovative CSP system design, which has thermal energy storage capability for base-load power generation.« less

  7. Conceptual design of an open-cycle ocean thermal energy conversion net power-producing experiment (OC-OTEC NPPE)

    SciTech Connect (OSTI)

    Bharathan, D.; Green, H.J.; Link, H.F.; Parsons, B.K.; Parsons, J.M.; Zangrando, F.

    1990-07-01

    This report describes the conceptual design of an experiment to investigate heat and mass transfer and to assess the viability of open-cycle ocean thermal energy conversion (OC-OTEC). The experiment will be developed in two stages, the Heat- and Mass-Transfer Experimental Apparatus (HMTEA) and the Net Power-Producing Experiment (NPPE). The goal for the HMTEA is to test heat exchangers. The goal for the NPPE is to experimentally verify OC-OTEC's feasibility by installing a turbine and testing the power-generating system. The design effort met the goals of both the HMTEA and the NPPE, and duplication of hardware was minimal. The choices made for the design resource water flow rates are consistent with the availability of cold and warm seawater as a result of the seawater systems upgrade carried out by the US Department of Energy (DOE), the state of Hawaii, and the Pacific International Center for High Technology Research. The choices regarding configuration of the system were made based on projected performance, degree of technical risk, schedule, and cost. The cost for the future phase of the design and the development of the HMTEA/NPPE is consistent with the projected future program funding levels. The HMTEA and NPPE were designed cooperatively by PICHTR, Argonne National Laboratory, and Solar Energy Research Institute under the guidance of DOE. The experiment will be located at the DOE's Seacoast Test Facility at the Natural Energy Laboratory of Hawaii, Kailua-Kona, Hawaii. 71 refs., 41 figs., 34 tabs.

  8. Analysis and design of high frequency link power conversion systems for fuel cell power conditioning 

    E-Print Network [OSTI]

    Song, Yu Jin

    2005-11-01

    simulations and experiments, and their trade-offs are described in detail using mathematical evaluation approach. The third study proposes a current-fed high frequency link direct dc-ac converter suitable for residential fuel cell power systems. The high...

  9. Dynamic Power Flow Controller: Compact Dynamic Phase Angle Regulators for Transmission Power Routing

    SciTech Connect (OSTI)

    2012-01-03

    GENI Project: Varentec is developing compact, low-cost transmission power controllers with fractional power rating for controlling power flow on transmission networks. The technology will enhance grid operations through improved use of current assets and by dramatically reducing the number of transmission lines that have to be built to meet increasing contributions of renewable energy sources like wind and solar. The proposed transmission controllers would allow for the dynamic control of voltage and power flow, improving the grid’s ability to dispatch power in real time to the places where it is most needed. The controllers would work as fail-safe devices whereby the grid would be restored to its present operating state in the event of a controller malfunction instead of failing outright. The ability to affordably and dynamically control power flow with adequate fail-safe switchgear could open up new competitive energy markets which are not possible under the current regulatory structure and technology base.

  10. Advanced fusion MHD power conversion using the CFAR (compact fusion advanced Rankine) cycle concept

    SciTech Connect (OSTI)

    Hoffman, M.A.; Campbell, R.; Logan, B.G.; Lawrence Livermore National Lab., CA )

    1988-10-01

    The CFAR (compact fusion advanced Rankine) cycle concept for a tokamak reactor involves the use of a high-temperature Rankine cycle in combination with microwave superheaters and nonequilibrium MHD disk generators to obtain a compact, low-capital-cost power conversion system which fits almost entirely within the reactor vault. The significant savings in the balance-of-plant costs are expected to result in much lower costs of electricity than previous concepts. This paper describes the unique features of the CFAR cycle and a high- temperature blanket designed to take advantage of it as well as the predicted performance of the MHD disk generators using mercury seeded with cesium. 40 refs., 8 figs., 3 tabs.

  11. Optimal Power Flow Based Demand Response Offer Price Optimization

    E-Print Network [OSTI]

    Lavaei, Javad

    Optimal Power Flow Based Demand Response Offer Price Optimization Zhen Qiu 1 Introduction-time energy balance. Demand response programs are offered by the utility companies to reduce the load response cost in exchange for load reduction. A considerable amount of papers have discussed the demand

  12. Thermal Unit Commitment Including Optimal AC Power Flow Constraints

    E-Print Network [OSTI]

    Thermal Unit Commitment Including Optimal AC Power Flow Constraints Carlos Murillo{Sanchez Robert J algorithm for unit commitment that employs a Lagrange relaxation technique with a new augmentation. This framework allows the possibility of committing units that are required for the VArs that they can produce

  13. Power flow analysis for amplifier design and energy harvesting

    E-Print Network [OSTI]

    Lindner, Douglas K.

    . In order to improve the efficiency of an active isolation system we analyze different feedback control energy on a active vibration isolation system it is important to understand the influence of the existingPower flow analysis for amplifier design and energy harvesting Nikola Vujica, Donald J. Leoa

  14. Exact Convex Relaxation of Optimal Power Flow in Radial Networks

    SciTech Connect (OSTI)

    Gan, LW; Li, N; Topcu, U; Low, SH

    2015-01-01

    The optimal power flow (OPF) problem determines a network operating point that minimizes a certain objective such as generation cost or power loss. It is nonconvex. We prove that a global optimum of OPF can be obtained by solving a second-order cone program, under a mild condition after shrinking the OPF feasible set slightly, for radial power networks. The condition can be checked a priori, and holds for the IEEE 13, 34, 37, 123-bus networks and two real-world networks.

  15. Friction pressure drop measurements and flow distribution analysis for LEU conversion study of MIT Research Reactor

    E-Print Network [OSTI]

    Wong, Susanna Yuen-Ting

    2008-01-01

    The MIT Nuclear Research Reactor (MITR) is the only research reactor in the United States that utilizes plate-type fuel elements with longitudinal fins to augment heat transfer. Recent studies on the conversion to low-enriched ...

  16. Probabilistic Vulnerability Assessment Based on Power Flow and Voltage Distribution

    SciTech Connect (OSTI)

    Ma, Jian; Huang, Zhenyu; Wong, Pak C.; Ferryman, Thomas A.

    2010-04-30

    Risk assessment of large scale power systems has been an important problem in power system reliability study. Probabilistic technique provides a powerful tool to solve the task. In this paper, we present the results of a study on probabilistic vulnerability assessment on WECC system. Cumulant based expansion method is applied to obtain the probabilistic distribution function (PDF) and cumulative distribution function (CDF) of power flows on transmission lines and voltage. Overall risk index based on the system vulnerability analysis is calculated using the WECC system. The simulation results based on WECC system is used to demonstrate the effectiveness of the method. The methodology can be applied to the risk analysis on large scale power systems.

  17. Primary Side Power Flow Control of Wireless Power Transfer for Electric Vehicle Charging

    SciTech Connect (OSTI)

    Miller, John M; Onar, Omer C; Chinthavali, Madhu Sudhan

    2015-01-01

    Various noncontacting methods of plug-in electric vehicle charging are either under development or now deployed as aftermarket options in the light-duty automotive market. Wireless power transfer (WPT) is now the accepted term for wireless charging and is used synonymously for inductive power transfer and magnetic resonance coupling. WPT technology is in its infancy; standardization is lacking, especially on interoperability, center frequency selection, magnetic fringe field suppression, and the methods employed for power flow regulation. This paper proposes a new analysis concept for power flow in WPT in which the primary provides frequency selection and the tuned secondary, with its resemblance to a power transmission network having a reactive power voltage control, is analyzed as a transmission network. Analysis is supported with experimental data taken from Oak Ridge National Laboratory s WPT apparatus. This paper also provides an experimental evidence for frequency selection, fringe field assessment, and the need for low-latency communications in the feedback path.

  18. A Formal Model for Verifying the Impact of Stealthy Attacks on Optimal Power Flow in Power Grids

    E-Print Network [OSTI]

    Wang, Yongge

    - mal Power Flow; Formal Model 1. INTRODUCTION Power system control centers employ a numberA Formal Model for Verifying the Impact of Stealthy Attacks on Optimal Power Flow in Power Grids the integrity of OPF and undermine the economic and secure system operation. We present a formal verification

  19. Resistive Network Optimal Power Flow: Uniqueness and Algorithms

    SciTech Connect (OSTI)

    Tan, CW; Cai, DWH; Lou, X

    2015-01-01

    The optimal power flow (OPF) problem minimizes the power loss in an electrical network by optimizing the voltage and power delivered at the network buses, and is a nonconvex problem that is generally hard to solve. By leveraging a recent development on the zero duality gap of OPF, we propose a second-order cone programming convex relaxation of the resistive network OPF, and study the uniqueness of the optimal solution using differential topology, especially the Poincare-Hopf Index Theorem. We characterize the global uniqueness for different network topologies, e.g., line, radial, and mesh networks. This serves as a starting point to design distributed local algorithms with global behaviors that have low complexity, are computationally fast, and can run under synchronous and asynchronous settings in practical power grids.

  20. Improving the Power Conversion Efficiency of Ultrathin Organic Solar Cells by Incorporating Plasmonic Effects of Spheroidal Metallic Nanoparticles

    E-Print Network [OSTI]

    Park, Namkyoo

    Improving the Power Conversion Efficiency of Ultrathin Organic Solar Cells by Incorporating be exploited to achieve efficient harvesting of solar energy. Notably, the incorporation of plasmonic effects can allow the light harvesting capability of a solar cell to be maintained even as the thickness

  1. Enhanced Light Trapping and Power Conversion Efficiency in Ultrathin Plasmonic Organic Solar Cells: A Coupled Optical-Electrical

    E-Print Network [OSTI]

    Park, Namkyoo

    much attention for the more efficient harvesting of solar energy. Notably, even as the thickness acceptor materials have been envisioned as a promising next generation energy harvesting device dueEnhanced Light Trapping and Power Conversion Efficiency in Ultrathin Plasmonic Organic Solar Cells

  2. Optimal Power Flow of Multiple Energy Carriers(Geidl and Andersson...

    Open Energy Info (EERE)

    signal, optimal power flow and economic dispatch The proposed method stabilized the power grid, reduced the marginal cost of electricity, and increased the marginal cost of...

  3. Using Heat and Chemistry to Make Products, Fuels, and Power: Thermochemical Conversion

    SciTech Connect (OSTI)

    2010-09-01

    Information about the Biomass Program's collaborative projects exploring thermochemical conversion processes that use heat and chemistry to convert biomass into a liquid or gaseous intermediate.

  4. Bilayer Polymer Solar Cells with Improved Power Conversion Efficiency and Enhanced Spectrum Coverage

    SciTech Connect (OSTI)

    Kekuda, Dhananjaya [Department of Physics, Manipal Institute of Technology, Manipal University, Manipal, India 576 104 (India); Chu, Chih-Wei [Research Center for Applied Science, Academia Sinica, Taipei, Taiwan 300 13 (China)

    2011-10-20

    We demonstrate the construction of an efficient bilayer polymer solar cell comprising of Poly(3-hexylthiophene)(P3HT) as a p-type semiconductor and asymmetric fullerene (C{sub 70}) as n-type counterparts. The bilayer configuration was very efficient compared to the individual layer performance and it behaved like a regular p-n junction device. The photovoltaic characteristic of the bilayers were studied under AM 1.5 solar radiation and the optimized device parameters are the following: Voc = 0.5V, Jsc = 10.1 mA/cm{sup 2}, FF = 0.60 and power conversion efficiency of 3.6 %. A high fill factor of {approx}0.6 was achieved, which is only slightly reduced at very intense illumination. Balanced mobility between p-and n-layers is achieved which is essential for achieving high device performance. Correlation between the crystallinity, morphology and the transport properties of the active layers is established. The External quantum efficiency (EQE) spectral distribution of the bilayer devices with different processing solvents correlates well with the trends of short circuit current densities (J{sub sc}) measured under illumination. Efficiency of the bilayer devices with rough P3HT layer was found to be about 3 times higher than those with a planar P3HT surface. Hence it is desirable to have a larger grains with a rough surface of P3HT layer for providing larger interfacial area for the exciton dissociation.

  5. Steam Generator Component Model in a Combined Cycle of Power Conversion Unit for Very High Temperature Gas-Cooled Reactor

    SciTech Connect (OSTI)

    Oh, Chang H; Han, James; Barner, Robert; Sherman, Steven R

    2007-06-01

    The Department of Energy and the Idaho National Laboratory are developing a Next Generation Nuclear Plant (NGNP), Very High Temperature Gas-Cooled Reactor (VHTR) to serve as a demonstration of state-of-the-art nuclear technology. The purpose of the demonstration is two fold 1) efficient low cost energy generation and 2) hydrogen production. Although a next generation plant could be developed as a single-purpose facility, early designs are expected to be dual-purpose. While hydrogen production and advanced energy cycles are still in its early stages of development, research towards coupling a high temperature reactor, electrical generation and hydrogen production is under way. A combined cycle is considered as one of the power conversion units to be coupled to the very high-temperature gas-cooled reactor (VHTR). The combined cycle configuration consists of a Brayton top cycle coupled to a Rankine bottoming cycle by means of a steam generator. A detailed sizing and pressure drop model of a steam generator is not available in the HYSYS processes code. Therefore a four region model was developed for implementation into HYSYS. The focus of this study was the validation of a HYSYS steam generator model of two phase flow correlations. The correlations calculated the size and heat exchange of the steam generator. To assess the model, those calculations were input into a RELAP5 model and its results were compared with HYSYS results. The comparison showed many differences in parameters such as the heat transfer coefficients and revealed the different methods used by the codes. Despite differences in approach, the overall results of heat transfer were in good agreement.

  6. Aalborg Universitet Power Flow Analysis Algorithm for Islanded LV Microgrids Including Distributed

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    Aalborg Universitet Power Flow Analysis Algorithm for Islanded LV Microgrids Including Distributed., & Guerrero, J. M. (2014). Power Flow Analysis Algorithm for Islanded LV Microgrids Including Distributed.aau.dk on: juli 04, 2015 #12;Power Flow Analysis Algorithm for Islanded LV Microgrids Including Distributed

  7. Aalborg Universitet Power flow analysis for DC voltage droop controlled DC microgrids

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    Aalborg Universitet Power flow analysis for DC voltage droop controlled DC microgrids Li, Chendan). Power flow analysis for DC voltage droop controlled DC microgrids. In Proceedings of the 11th.aau.dk on: juli 07, 2015 #12;Power flow analysis for DC voltage droop controlled DC microgrids Chendan Li

  8. Power-Aware Scheduling for Makespan and Flow David P. Bunde

    E-Print Network [OSTI]

    Bunde, David

    Power-Aware Scheduling for Makespan and Flow David P. Bunde Department of Computer Science Knox different amounts of work. For total flow, we show that the optimal flow corresponding to a particular in computer systems. This is most obvious for battery-powered systems such as laptops because processor power

  9. Power Control and Optimization of Photovoltaic and Wind Energy Conversion Systems /

    E-Print Network [OSTI]

    Ghaffari, Azad

    2013-01-01

    Wind Energy Conversion Systems using Extremum Seeking,” Submitted to the IEEE Transactions on Control Systems Technology. (Wind Energy Conversion Systems using Extremum Seeking,” Submitted to the IEEE Transactions on Control Systems Technology.current wind technology has limitations in terms of energy

  10. 2892 IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 29, NO. 6, NOVEMBER 2014 Optimal Power Flow in Direct Current Networks

    E-Print Network [OSTI]

    Wierman, Adam

    .g., photovoltaic panels, wind turbines, electric vehicles, electronic appliances, and fuel cells, are easier2892 IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 29, NO. 6, NOVEMBER 2014 Optimal Power Flow in Direct Current Networks Lingwen Gan and Steven H. Low, Fellow, IEEE Abstract--The optimal power flow (OPF

  11. Power Control and Optimization of Photovoltaic and Wind Energy Conversion Systems /

    E-Print Network [OSTI]

    Ghaffari, Azad

    2013-01-01

    Power Point Tracking in Photovoltaic Systems . . . 4.1DC- DC converter photovoltaic systems: power optimizationgrid-connected photovoltaic systems,” IET Electric Power

  12. Switched-capacitor step-down rectifier for low-voltage power conversion

    E-Print Network [OSTI]

    Li, Wei

    This paper presents a switched-capacitor rectifier that provides step down voltage conversion from an ac input voltage to a dc output. Coupled with current-drive source, low-loss and high step-down rectification is realized. ...

  13. Power Control and Optimization of Photovoltaic and Wind Energy Conversion Systems /

    E-Print Network [OSTI]

    Ghaffari, Azad

    2013-01-01

    both AC drives and wind energy Turbine, shaft, and Gear BoxWind Energy Conversion Systems using Extremum Seeking Wind turbines (wind turbines: standard and adaptive techniques for maximizing energy

  14. Technology Development Program for an Advanced Potassium Rankine Power Conversion System Compatible with Several Space Reactor Designs

    SciTech Connect (OSTI)

    Yoder, G.L.

    2005-10-03

    This report documents the work performed during the first phase of the National Aeronautics and Space Administration (NASA), National Research Announcement (NRA) Technology Development Program for an Advanced Potassium Rankine Power Conversion System Compatible with Several Space Reactor Designs. The document includes an optimization of both 100-kW{sub e} and 250-kW{sub e} (at the propulsion unit) Rankine cycle power conversion systems. In order to perform the mass optimization of these systems, several parametric evaluations of different design options were investigated. These options included feed and reheat, vapor superheat levels entering the turbine, three different material types, and multiple heat rejection system designs. The overall masses of these Nb-1%Zr systems are approximately 3100 kg and 6300 kg for the 100- kW{sub e} and 250-kW{sub e} systems, respectively, each with two totally redundant power conversion units, including the mass of the single reactor and shield. Initial conceptual designs for each of the components were developed in order to estimate component masses. In addition, an overall system concept was presented that was designed to fit within the launch envelope of a heavy lift vehicle. A technology development plan is presented in the report that describes the major efforts that are required to reach a technology readiness level of 6. A 10-year development plan was proposed.

  15. IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 15, NO. 2, MAY 2000 535 Stability-Constrained Optimal Power Flow

    E-Print Network [OSTI]

    IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 15, NO. 2, MAY 2000 535 Stability-Constrained Optimal Power Flow Deqiang Gan, Member, IEEE, Robert J. Thomas, Fellow, IEEE, and Ray D. Zimmerman, Member, IEEE

  16. Observation of Ion-Cyclotron-Frequency Mode-Conversion Flow Drive...

    Office of Scientific and Technical Information (OSTI)

    larger than that in ICRF minority heated plasmas at the same rf power or stored energy. The central Vsub phi responds to Psub rf faster than the outer regions, and...

  17. Risk-Mitigated Optimal Power Flow for Wind Powered Grids Emma Sjodin, Dennice F. Gayme and Ufuk Topcu

    E-Print Network [OSTI]

    Wierman, Adam

    Risk-Mitigated Optimal Power Flow for Wind Powered Grids Emma Sj¨odin, Dennice F. Gayme and Ufuk." High grid penetrations of solar or wind power pose a number of operational challenges and it is widely is the use of large-scale grid-integrated energy storage. The role of energy storage in power systems has

  18. Application of Flow Battery in Marine Current Turbine System for Daily Power Management

    E-Print Network [OSTI]

    Brest, Université de

    Application of Flow Battery in Marine Current Turbine System for Daily Power Management Zhibin Zhou focuses on a grid-connected MCT system and proposes using vanadium redox flow battery (VRB) energy storage and to guarantee the expected power injection to the local grid. Keywords--Marine current turbine, flow battery

  19. Parallel Processing Implementation of the Unit Commitment Problem with Full AC Power Flow Constraints

    E-Print Network [OSTI]

    Parallel Processing Implementation of the Unit Commitment Problem with Full AC Power Flow power flow model, which per- mits addressing voltage limits, as well as more real- istic branch flow specific kbd is achieved. Lagrangian relaxation allows trading a direct solution approach exhibiting

  20. Method and apparatus for low power analog-to-digital conversion

    DOE Patents [OSTI]

    De Geronimo, Gianluigi; Nambiar, Neena

    2013-10-01

    A method and apparatus for analog-to-digital conversion. An Analog-to-Digital Converter (ADC) includes M ADC.sub.j, j=1, 2, . . . , M. Each ADC.sub.j comprises a number of cells each of which comprises a first switch, a second switch, a current sink and an inverter. An inverter of a cell in an ADC.sub.j changes state in response to a current associate with an input signal of the ADC.sub.j exceeding a threshold, thus switching on the next cell. Each ADC.sub.j is enabled to perform analog-to-digital conversion on a residual current of a previous ADC.sub.j-1 after the previous ADC.sub.j-1 has completed its analog-to-digital conversion and has been disabled.

  1. Power Control and Optimization of Photovoltaic and Wind Energy Conversion Systems /

    E-Print Network [OSTI]

    Ghaffari, Azad

    2013-01-01

    2011. [2] ——, “High altitude wind power systems: A survey onidea of harnessing high altitude wind power using a tetheredComputed power densities in high altitude winds exceed a 10

  2. Power Control and Optimization of Photovoltaic and Wind Energy Conversion Systems /

    E-Print Network [OSTI]

    Ghaffari, Azad

    2013-01-01

    be realized by capturing wind power at altitudes over the2011. [2] ——, “High altitude wind power systems: A survey onOckels, “Optimal cross-wind towing and power generation with

  3. Maximizing the Performance of Wind Turbines with Nonlinear Aeroservoelastic Power Flow Control

    E-Print Network [OSTI]

    1 Maximizing the Performance of Wind Turbines with Nonlinear Aeroservoelastic Power Flow Control by a wind turbine by operating at the edge of dynamic stall. This paper applies a novel nonlinear power flow of the first torsional mode of a nominal 5 MW rated power wind turbine blade. This model is analyzed using

  4. Edinburgh Research Explorer Local solutions of the optimal power flow problem

    E-Print Network [OSTI]

    Millar, Andrew J.

    law (KVL), which describes the flow of power in transmission lines, and is a nonlinear function of bus is to find a steady state operating point that minimizes the cost of electric power generation whileEdinburgh Research Explorer Local solutions of the optimal power flow problem Citation

  5. Nonlinear Power Flow Control Design: Utilizing Exergy, Entropy, Static and Dynamic

    E-Print Network [OSTI]

    Nonlinear Power Flow Control Design: Utilizing Exergy, Entropy, Static and Dynamic Stability (future electric power grid control, wind turbine load alleviation control, and novel micro-grid control provide the theoretical foundations necessary to view control design as power flow control problem

  6. Optimal power flow in microgrids using event-triggered optimization Pu Wan and Michael D. Lemmon

    E-Print Network [OSTI]

    Lemmon, Michael

    Optimal power flow in microgrids using event-triggered optimization Pu Wan and Michael D. Lemmon Abstract-- Microgrids are power generation and distribution systems in which users and generators-triggered distributed optimization algorithm to solve the optimal power flow (OPF) problem in microgrids. Under event

  7. A MultiPhase Power Flow Model for Grid Analysis A. P. Sakis Meliopoulos

    E-Print Network [OSTI]

    A MultiPhase Power Flow Model for µµµµGrid Analysis A. P. Sakis Meliopoulos School of Electrical power system with distributed energy sources forming a microgrid (µGrid). The µGrid is a radial multiphase power flow analysis method that provides exact solution to the operation of the µGrid under steady

  8. 6th International Symposium on Multiphase Flow, Heat Mass Transfer and Energy Conversion Xi'an, China, 11-15 July 2009

    E-Print Network [OSTI]

    Khandekar, Sameer

    from a variety of sources including fossil fuels (coal, natural gas, LPG, gasoline, diesel, methane in the process. Use of natural gas or naphtha as a raw material is an industrial process. Typical reactions6th International Symposium on Multiphase Flow, Heat Mass Transfer and Energy Conversion Xi

  9. Precision control of high temperature furnaces using an auxiliary power supply and charged practice current flow

    DOE Patents [OSTI]

    Pollock, George G. (San Ramon, CA)

    1997-01-01

    Two power supplies are combined to control a furnace. A main power supply heats the furnace in the traditional manner, while the power from the auxiliary supply is introduced as a current flow through charged particles existing due to ionized gas or thermionic emission. The main power supply provides the bulk heating power and the auxiliary supply provides a precise and fast power source such that the precision of the total power delivered to the furnace is improved.

  10. Precision control of high temperature furnaces using an auxiliary power supply and charged particle current flow

    DOE Patents [OSTI]

    Pollock, G.G.

    1997-01-28

    Two power supplies are combined to control a furnace. A main power supply heats the furnace in the traditional manner, while the power from the auxiliary supply is introduced as a current flow through charged particles existing due to ionized gas or thermionic emission. The main power supply provides the bulk heating power and the auxiliary supply provides a precise and fast power source such that the precision of the total power delivered to the furnace is improved. 5 figs.

  11. Power Control and Optimization of Photovoltaic and Wind Energy Conversion Systems /

    E-Print Network [OSTI]

    Ghaffari, Azad

    2013-01-01

    Output power leveling of wind turbine generator for allpower map of Distributed Generators (DG), including Photo- voltaic (PV) and WindGenerator (IG) stator. Introduction A variable speed wind turbine generates power

  12. Power Control and Optimization of Photovoltaic and Wind Energy Conversion Systems /

    E-Print Network [OSTI]

    Ghaffari, Azad

    2013-01-01

    design that has good performance robustness to uncertainty, and faster transient performance, allowing for power tracking under rapidly varying wind

  13. Conversion of raw carbonaceous fuels

    DOE Patents [OSTI]

    Cooper, John F. (Oakland, CA)

    2007-08-07

    Three configurations for an electrochemical cell are utilized to generate electric power from the reaction of oxygen or air with porous plates or particulates of carbon, arranged such that waste heat from the electrochemical cells is allowed to flow upwards through a storage chamber or port containing raw carbonaceous fuel. These configurations allow combining the separate processes of devolatilization, pyrolysis and electrochemical conversion of carbon to electric power into a single unit process, fed with raw fuel and exhausting high BTU gases, electric power, and substantially pure CO.sub.2 during operation.

  14. Time series power flow analysis for distribution connected PV generation.

    SciTech Connect (OSTI)

    Broderick, Robert Joseph; Quiroz, Jimmy Edward; Ellis, Abraham; Reno, Matthew J.; Smith, Jeff; Dugan, Roger

    2013-01-01

    Distributed photovoltaic (PV) projects must go through an interconnection study process before connecting to the distribution grid. These studies are intended to identify the likely impacts and mitigation alternatives. In the majority of the cases, system impacts can be ruled out or mitigation can be identified without an involved study, through a screening process or a simple supplemental review study. For some proposed projects, expensive and time-consuming interconnection studies are required. The challenges to performing the studies are twofold. First, every study scenario is potentially unique, as the studies are often highly specific to the amount of PV generation capacity that varies greatly from feeder to feeder and is often unevenly distributed along the same feeder. This can cause location-specific impacts and mitigations. The second challenge is the inherent variability in PV power output which can interact with feeder operation in complex ways, by affecting the operation of voltage regulation and protection devices. The typical simulation tools and methods in use today for distribution system planning are often not adequate to accurately assess these potential impacts. This report demonstrates how quasi-static time series (QSTS) simulation and high time-resolution data can be used to assess the potential impacts in a more comprehensive manner. The QSTS simulations are applied to a set of sample feeders with high PV deployment to illustrate the usefulness of the approach. The report describes methods that can help determine how PV affects distribution system operations. The simulation results are focused on enhancing the understanding of the underlying technical issues. The examples also highlight the steps needed to perform QSTS simulation and describe the data needed to drive the simulations. The goal of this report is to make the methodology of time series power flow analysis readily accessible to utilities and others responsible for evaluating potential PV impacts.

  15. Chip-Scale Power Conversion for LED Lighting: Integrated Power Chip Converter for Solid-State Lighting

    SciTech Connect (OSTI)

    None

    2010-10-01

    ADEPT Project: Teledyne is developing cost-effective power drivers for energy-efficient LED lights that fit on a compact chip. These power drivers are important because they transmit power throughout the LED device. Traditional LED driver components waste energy and don't last as long as the LED itself. They are also large and bulky, so they must be assembled onto a circuit board separately which increases the overall manufacturing cost of the LED light. Teledyne is shrinking the size and improving the efficiency of its LED driver components by using thin layers of an iron magnetic alloy and new gallium nitride on silicon devices. Smaller, more efficient components will enable the drivers to be integrated on a single chip, reducing costs. The new semiconductors in Teledyne's drivers can also handle higher levels of power and last longer without sacrificing efficiency. Initial applications for Teledyne's LED power drivers include refrigerated grocery display cases and retail lighting.

  16. Distributed Multi-Period Optimal Power Flow for Demand Response in Microgrids

    E-Print Network [OSTI]

    Yeoh, William

    Distributed Multi-Period Optimal Power Flow for Demand Response in Microgrids Paul Scott1 direction method of multipliers (ADMM), can be adapted to remain practical in this challenging microgrid discrete decisions. Our experiments on a suburb-sized microgrid show that the AC power flows and a simple

  17. Journal of Power Sources 128 (2004) 5460 Microfluidic fuel cell based on laminar flow

    E-Print Network [OSTI]

    Kenis, Paul J. A.

    2004-01-01

    Journal of Power Sources 128 (2004) 54­60 Microfluidic fuel cell based on laminar flow Eric R compartments. While these PEM-type fuel cell designs have great promise to become the power source of choice a novel microfluidic fuel cell concept that utilizes the occurrence of multi-stream laminar flow

  18. A Comparison of the AC and DC Power Flow Models for LMP Calculations

    E-Print Network [OSTI]

    power flow model for LMP-based market calculations. The paper first provides a general discussion values include generator AVR status, LTC and phase shifting transformer tap positions, discrete switched shifting transformers is often dependent upon the transformer's tap value. Last, the power flow models

  19. Optimal Power Flow Formulation in Market of Retail Wheeling Taiyou Yong, Student Member, IEEE Robert Lasseter, Fellow, IEEE

    E-Print Network [OSTI]

    Optimal Power Flow Formulation in Market of Retail Wheeling Taiyou Yong, Student Member, IEEE distribution in the new retail wheeling market. Formation of optimal power flow (OPF) problem, in which concerns on optimal power flow arise in the retail wheeling market. In the deregulated power system

  20. Abstract--The optimal power flow (OPF) problem is a critical problem for power generation and is generally non-convex. This

    E-Print Network [OSTI]

    Lavaei, Javad

    1 Abstract-- The optimal power flow (OPF) problem is a critical problem for power generation flow on the line P: vector of active power generations Q: vector of reactive power generations L: loss/reactive power generation limits. Given the practical importance of the problem, a great many studies have been

  1. Efficient Switches for Solar Power Conversion: Four Quadrant GaN Switch Enabled Three Phase Grid-Tied Microinverters

    SciTech Connect (OSTI)

    2012-02-13

    Solar ADEPT Project: Transphorm is developing power switches for new types of inverters that improve the efficiency and reliability of converting energy from solar panels into useable electricity for the grid. Transistors act as fast switches and control the electrical energy that flows in an electrical circuit. Turning a transistor off opens the circuit and stops the flow of electrical current; turning it on closes the circuit and allows electrical current to flow. In this way a transistor can be used to convert DC from a solar panel into AC for use in a home. Transphorm’s transistors will enable a single semiconductor device to switch electrical currents at high-voltage in both directions—making the inverter more compact and reliable. Transphorm is using Gallium Nitride (GaN) as a semiconductor material in its transistors instead of silicon, which is used in most conventional transistors, because GaN transistors have lower losses at higher voltages and switching frequencies.

  2. Where solar thermal meets photovoltaic for high-efficiency power conversion

    E-Print Network [OSTI]

    Bierman, David M. (David Matthew)

    2014-01-01

    To develop disruptive techniques which generate power from the Sun, one must understand the aspects of existing technologies that limit performance. Solar thermal and solar photovoltaic schemes dominate today's solar market ...

  3. Laboratory for Energy Conversion Science and Technology to Power & Develop the World

    E-Print Network [OSTI]

    Daraio, Chiara

    in order to support decision-making and policy planing. Mesoscale weather model Transmission grid model from transportation to electricity production to energy consumption society is powered by energy

  4. Power Control and Optimization of Photovoltaic and Wind Energy Conversion Systems /

    E-Print Network [OSTI]

    Ghaffari, Azad

    2013-01-01

    power at the wind turbine shaft as the cost func- tion asstructure, cost, and land occupation. In wind turbines, thecost. Since the P&O method adds delay, it is not practical for medium- and large-inertia wind turbine

  5. A Power-Law Formulation of Laminar Flow in Short Pipes Max Sherman

    E-Print Network [OSTI]

    A Power-Law Formulation of Laminar Flow in Short Pipes Max Sherman Indoor Environment Program ABSTRACT This report develops a theoretical description of the hydrodynamic relationship based on a power pipes can be described with a simple power law dependence on pressure, but that the exponent

  6. Power Flow Analysis Algorithm for Islanded LV Microgrids Including Distributed Generator Units with

    E-Print Network [OSTI]

    Chaudhary, Sanjay

    Power Flow Analysis Algorithm for Islanded LV Microgrids Including Distributed Generator Units power system. Being able to operate in both grid-connected and islanded mode, a microgrid manages and controls distributed energy resources, energy storage systems and loads, most of them are power electronic

  7. A Novel Power Flow Method for Long Term Frequency Stability Analysis 

    E-Print Network [OSTI]

    Yan, Wenjin

    2013-05-06

    This thesis presents a novel approach for a power system to find a practical power flow solution when all the generators in the system have hit their real power output limits, such as some generator units shutting down or load outages. The approach...

  8. Multi-Level DC/DC Power Conversion System with Multiple DC Sources

    E-Print Network [OSTI]

    Tolbert, Leon M.

    boost converter. Experimental results are provided to confirm the analysis and control concept. I, instead of connecting all batteries in series as one power source and a bi-directional boost converter. INTRODUCTION Traditional dc/dc converters require at least one inductive component, which is bulky, heavy

  9. POWER FLOW ANALYSIS OF ELECTROSTRICTIVE ACTUATORS DRIVEN BYSWITCHMODE AMPLIFIERS

    E-Print Network [OSTI]

    Lindner, Douglas K.

    of that energy. We adopt this view in this paper. The analysis in this paper is motivated by the smart skin being Consider the flow of energy through this smart skin. Electrical energy is supplied to the smart skin from energy into mechanical energy. This mechanical energy then flows from the smart skin into the surrounding

  10. DC Optimal Power Flow Formulation in AMES Leigh Tesfatsion

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    wholesale power market testbed. I. AMES TESTBED The latest version of AMES (Agent-based Modeling is measured by the net earnings it secures for itself through the purchase of power in the day- ahead market and the resale of this power to its retail cus- tomers. During the morning of each day D, each LSE j reports

  11. Fuel processor for fuel cell power system. [Conversion of methanol into hydrogen

    DOE Patents [OSTI]

    Vanderborgh, N.E.; Springer, T.E.; Huff, J.R.

    1986-01-28

    A catalytic organic fuel processing apparatus, which can be used in a fuel cell power system, contains within a housing a catalyst chamber, a variable speed fan, and a combustion chamber. Vaporized organic fuel is circulated by the fan past the combustion chamber with which it is in indirect heat exchange relationship. The heated vaporized organic fuel enters a catalyst bed where it is converted into a desired product such as hydrogen needed to power the fuel cell. During periods of high demand, air is injected upstream of the combustion chamber and organic fuel injection means to burn with some of the organic fuel on the outside of the combustion chamber, and thus be in direct heat exchange relation with the organic fuel going into the catalyst bed.

  12. Large Parabolic Dish collectors with small gas-turbine, Stirling engine or photovoltaic power conversion systems

    SciTech Connect (OSTI)

    Gehlisch, K.; Heikal, H.; Mobarak, A.; Simon, M.

    1982-08-01

    A comparison for different solar thermal power plants is presented and demonstrates that the large parabolic dish in association with a gas turbine or a Sterling engine could be a competitive system design in the net power range of 50-1000KW. The important advantages of the Large Parabolic Dish concept compared to the Farm and Tower concept are discussed: concentration ratios up to 5000 and uniform heat flux distribution throughout the day which allow very high receiver temperatures and therefor high receiver efficiency to operate effectively Stirling motors or small gas turbines in the mentioned power range with an overall efficiency of 20 to 30%. The high focal plane concentration leads to the efficient use of ceramic materials for receivers of the next generation, applicable in temperature ranges up to 1,300 /sup 0/C for energy converters. Besides the production of electricity, the system can supply process heat in the temperature range of 100 to 400 /sup 0/C as waste heat from the gas turbo converter and heat at temperature levels from 500 to 900 /sup 0/C (1300 /sup 0/C) directly out of the receiver.

  13. Free Flow Power Partners to Improve Hydrokinetic Turbine Performance...

    Energy Savers [EERE]

    as the device performed as expected, with no discernible harm to river-dwelling fish. Free Flow has also completed preliminary designs of utility-scale installations at a...

  14. A three phase load flow algorithm for Shipboard Power Systems 

    E-Print Network [OSTI]

    Medina-Calder?on, M?onica M

    2003-01-01

    -Seidel and/or Newton Raphson techniques, were primarily developed for transmission system analysis. Distribution load flow analysis must incorporate its unique characteristics such as unbalanced loads, distributed loads, radial network structure, and one...

  15. Design issues concerning Iran`s Bushehr nuclear power plant VVER-1000 conversion

    SciTech Connect (OSTI)

    Carson, C.F.

    1996-12-31

    On January 8, 1995, the Atomic Energy Organization of Iran (AEOI) signed a contract for $800 million with the Russian Federation Ministry for Atomic Energy (Minatom) to complete Bushehr nuclear power plant (BNPP) unit 1. The agreement called for a Russian VVER-1000/320 pressurized water reactor (PWR) to be successfully installed into the existing German-built BNPP facilities in 5 yr. System design differences, bomb damage, and environmental exposure are key issues with which Minatom must contend in order to fulfill the contract. The AEOI under the Shah of Iran envisioned Bushehr as the first of many nuclear power plants, with Iran achieving 24 GW(electric) by 1993 and 34 GW(electric) by 2000. Kraftwerk Union AG (KWU) began construction of the two-unit plant near the Persian Gulf town of Halileh in 1975. Unit 1 was {approx}80% complete and unit 2 was {approx}50% complete when construction was interrupted by the 1979 Iranian Islamic revolution. Despite repeated AEOI attempts to lure KWU and other companies back to Iran to complete the plant, Western concerns about nuclear proliferation in Iran and repeated bombings of the plant during the 1980-1988 Iran-Iraq war dissuaded Germany from resuming construction.

  16. Analysis of operating data related to power and flow distribution in a PWR

    E-Print Network [OSTI]

    Herbin, Henry Christophe

    1974-01-01

    The analysis of the effects of the uncertainties associated with temperature and power measurements in the Connecticut Yankee Reactor leads to the evaluation of the uncertainty associated with the effective flow factor. ...

  17. Assessment of microwave power flow for reflectometry measurements in tokamak plasmas

    E-Print Network [OSTI]

    Gourdain, P-A; Peebles, W. A.

    2008-01-01

    of incident and reflected microwave rays for O-mode and X-Assessment of microwave power flow for reflectometryLos Angeles, CA 90095-1547 Microwave diagnostics, such as

  18. RHF RELAP5 Model and Preliminary Loss-Of-Offsite-Power Simulation Results for LEU Conversion

    SciTech Connect (OSTI)

    Licht, J. R.; Bergeron, A.; Dionne, B.; Thomas, F.

    2014-08-01

    The purpose of this document is to describe the current state of the RELAP5 model for the Institut Laue-Langevin High Flux Reactor (RHF) located in Grenoble, France, and provide an update to the key information required to complete, for example, simulations for a loss of offsite power (LOOP) accident. A previous status report identified a list of 22 items to be resolved in order to complete the RELAP5 model. Most of these items have been resolved by ANL and the RHF team. Enough information was available to perform preliminary safety analyses and define the key items that are still required. Section 2 of this document describes the RELAP5 model of RHF. The final part of this section briefly summarizes previous model issues and resolutions. Section 3 of this document describes preliminary LOOP simulations for both HEU and LEU fuel at beginning of cycle conditions.

  19. Nanorod Niobium Oxide as Powerful Catalysts for an All Vanadium Redox Flow Battery

    SciTech Connect (OSTI)

    Li, Bin; Gu, Meng; Nie, Zimin; Wei, Xiaoliang; Wang, Chong M.; Sprenkle, Vincent L.; Wang, Wei

    2014-01-01

    Graphite felts (GFs), as typical electrode materials for all vanadium redox flow batteries (VRBs), limit the cell operation to low current density because of their poor kinetic reversibility and electrochemical activity. Here, in order to address this issue we report an electrocatalyst, Nb2O5, decorating the surface of GFs to reduce the activation barrier for redox conversion. Nb2O5 nanofibers with monoclinic phases are synthesized by hydrothermal method and deposited on GFs, which is confirmed to have catalytic effects towards redox couples of V(II)/V(III) at the negative side and V(IV)/V(V) at the positive side, and thus applied in both electrodes of VRB cells. Due to the low conductivity of Nb2O5, the performance of electrodes heavily depends on the nano size and uniform distribution of catalysts on GFs surfaces. The addition of the water-soluble compounds containing W element into the precursor solutions facilitates the precipitation of nanofibers on the GFs. Accordingly, an optimal amount of W-doped Nb2O5 nanofibers with weaker agglomeration and better distribution on GFs surfaces are obtained, leading to significant improvement of the electrochemical performances of VRB cells particularly under the high power operation. The corresponding energy efficiency is enhanced by 10.7 % under the operation of high charge/discharge current density (150 mA•cm-2) owing to faster charge transfer as compared with that without catalysts. These results suggest that Nb2O5 based nanofibers-decorating GFs hold great promise as high-performance electrodes for VRB applications.

  20. Optimal Power Flow: Closing the Loop over Corrupted Data

    E-Print Network [OSTI]

    Johansson, Karl Henrik

    application are the Supervisory Control and Data Acquisition (SCADA) systems. In power networks, the SCADA System. Modern SCADA/EMS systems collect large amounts of measurement data and, using a State Estimator attack. We denote the data corruption by a. cyber attacks on SCADA/EMS systems operating power net- works

  1. Voltage multi-stability in distribution grids with power flow reversal

    E-Print Network [OSTI]

    Hung D. Nguyen; Konstantin Turitsyn

    2014-07-08

    High levels of penetration of distributed generation and aggressive reactive power compensation with modern power electronics may result in the reversal of active and reactive power flows in future distribution grids. The voltage stability of these operating conditions may be very different from the more traditional power consumption regime. We study the stability characteristics of distribution networks with reversed power flow. After introducing a universal algebraic approach to characterize all the solutions of the power flow equations, we show that new solutions appear in the reversed power flow regime even in the simplest three bus systems. We show that the some of these solutions are stable and the system may exhibit a phenomenon of multistability, where multiple stable equilibria co-exist at the given set of parameters, and the system may converge to an undesirable equilibrium after a disturbance. These predictions are validated with dynamic simulations of two different systems. Under certain conditions the new states are viable and may be characterized by relatively high voltages. Possible approaches towards reactive power/voltage regulation as well as permissible distributed generation capacity in future power systems are proposed and discussed in the end of the paper.

  2. Numerical Analysis of Fifth-Harmonic Conversion of Low-Power Pulsed Nd:YAG Laser with Resonance of Second Harmonic

    E-Print Network [OSTI]

    Kung, Andy

    Numerical Analysis of Fifth-Harmonic Conversion of Low-Power Pulsed Nd:YAG Laser with Resonance of Second Harmonic Lien-Bee CHANG1Ă , S. C. WANG1 and A. H. KUNG1;2 1 Institute of Electro March 13, 2003) A model for the fifth-harmonic generation of pulsed IR lasers involving an external ring

  3. Thermoelectric Conversion of Waste Heat to Electricity in an IC Engine Powered Vehicle

    SciTech Connect (OSTI)

    2012-01-31

    The thermoelectric generator shorting system provides the capability to monitor and short-out individual thermoelectric couples in the event of failure. This makes the series configured thermoelectric generator robust to individual thermoelectric couple failure. Open circuit detection of the thermoelectric couples and the associated short control is a key technique to ensure normal functionality of the TE generator under failure of individual TE couples. This report describes a five-year effort whose goal was the understanding the issues related to the development of a thermoelectric energy recovery device for a Class-8 truck. Likely materials and important issues related to the utility of this generator were identified. Several prototype generators were constructed and demonstrated. The generators developed demonstrated several new concepts including advanced insulation, couple bypass technology and the first implementation of skutterudite thermoelectric material in a generator design. Additional work will be required to bring this system to fruition. However, such generators offer the possibility of converting energy that is otherwise wasted to useful electric power. Uur studies indicate that this can be accomplished in a cost-effective manner for this application.

  4. A COMPUTATIONAL ANALYSIS OF THE OPTIMAL POWER FLOW PROBLEM

    E-Print Network [OSTI]

    under these contingencies was exemplified by the blackout in the North American power grid during 2003. The reason for the blackout was a failure of only a handful of contingencies in the network [8

  5. Flow Shop Scheduling with Peak Power Consumption Constraints

    E-Print Network [OSTI]

    2012-09-23

    voltages to produce a preemptive task schedule that minimizes total energy ... since it affects the power supply and cooling technologies in the design of ...... The primary role of the two heuristic algorithms described above in our study is to

  6. Islanding model for preventing wide-area blackouts and the issue of local solutions of the optimal power flow problem. 

    E-Print Network [OSTI]

    Bukhsh, Waqquas Ahmed

    2014-07-01

    Optimization plays a central role in the control and operation of electricity power networks. In this thesis we focus on two very important optimization problems in power systems. The first is the optimal power flow ...

  7. Interline Photovoltaic (I-PV) power system - A novel concept of power flow control and management

    E-Print Network [OSTI]

    Khadkikar, Vinod

    This paper presents a new system configuration for a large-scale Photovoltaic (PV) power system with multi-line transmission/distribution networks. A PV power plant is reconfigured in a way that two adjacent power system ...

  8. 1464 IEEE TRANSACTIONS ON SMART GRID, VOL. 4, NO. 3, SEPTEMBER 2013 Distributed Optimal Power Flow

    E-Print Network [OSTI]

    Giannakis, Georgios

    --Distributed optimization, distribution feeders, microgrids, optimal power flow, semidefinite relaxation. I. INTRODUCTION MICROGRIDS are portions of a power distribution net- work located downstream of the distribution substation) and energy storage devices [1]. A microgrid can operate in either grid-connected, islanded, or hybrid modes

  9. Aalborg Universitet Power flow analysis for droop controlled LV hybrid AC-DC microgrids with virtual

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    Aalborg Universitet Power flow analysis for droop controlled LV hybrid AC-DC microgrids controlled LV hybrid AC-DC microgrids with virtual impedance. In Proceedings of the IEEE Power & Energy Interlinking converter PV WT IBS DC microgrid DC microgrid AC microgrid AC Load Figure 1. Structure

  10. High Average Power Laser Gain Medium With Low Optical Distortion Using A Transverse Flowing Liquid Host

    DOE Patents [OSTI]

    Comaskey, Brian J. (Walnut Creek, CA); Ault, Earl R. (Livermore, CA); Kuklo, Thomas C. (Oakdale, CA)

    2005-07-05

    A high average power, low optical distortion laser gain media is based on a flowing liquid media. A diode laser pumping device with tailored irradiance excites the laser active atom, ion or molecule within the liquid media. A laser active component of the liquid media exhibits energy storage times longer than or comparable to the thermal optical response time of the liquid. A circulation system that provides a closed loop for mixing and circulating the lasing liquid into and out of the optical cavity includes a pump, a diffuser, and a heat exchanger. A liquid flow gain cell includes flow straighteners and flow channel compression.

  11. Test Requirements and Conceptual Design for a Potassium Test Loop to Support an Advanced Potassium Rankine Cycle Power Conversion Systems

    SciTech Connect (OSTI)

    Yoder, JR.G.L.

    2006-03-08

    Parameters for continuing the design and specification of an experimental potassium test loop are identified in this report. Design and construction of a potassium test loop is part of the Phase II effort of the project ''Technology Development Program for an Advanced Potassium Rankine Power Conversion System''. This program is supported by the National Aeronautics and Space Administration. Design features for the potassium test loop and its instrumentation system, specific test articles, and engineered barriers for ensuring worker safety and protection of the environment are described along with safety and environmental protection requirements to be used during the design process. Information presented in the first portion of this report formed the basis to initiate the design phase of the program; however, the report is a living document that can be changed as necessary during the design process, reflecting modifications as additional design details are developed. Some portions of the report have parameters identified as ''to be determined'' (TBD), reflecting the early stage of the overall process. In cases where specific design values are presently unknown, the report attempts to document the quantities that remain to be defined in order to complete the design of the potassium test loop and supporting equipment.

  12. Power flow tracing in a simplified highly renewable European electricity network

    E-Print Network [OSTI]

    Tranberg, Bo; Rodriguez, Rolando A; Andresen, Gorm B; Schäfer, Mirko; Greiner, Martin

    2015-01-01

    The increasing transmission capacity needs in a future energy system raise the question how associated costs should be allocated to the users of a strengthened power grid. In contrast to straightforward oversimplified methods, a flow tracing based approach provides a fair and consistent nodal usage and thus cost assignment of transmission investments. This technique follows the power flow through the network and assigns the link capacity usage to the respective sources or sinks using a diffusion-like process, thus taking into account the underlying network structure and injection pattern. As a showcase, we apply power flow tracing to a simplified model of the European electricity grid with a high share of renewable wind and solar power generation, based on long-term weather and load data with an hourly temporal resolution.

  13. Local Solutions of Optimal Power Flow Waqquas A. Bukhsh, Andreas Grothey, Ken McKinnon, and Paul Trodden

    E-Print Network [OSTI]

    Grothey, Andreas

    is primarily due to Kirchhoff's voltage law (KVL), which describes the flow of power in transmission lines that minimizes the cost of electric power generation while satisfying operating constraints and meeting demandLocal Solutions of Optimal Power Flow Waqquas A. Bukhsh, Andreas Grothey, Ken McKinnon, and Paul

  14. Correlating High Power Conversion Efficiency of PTB7:PC71BM Inverted Organic Solar Cells to Nanoscale Structure

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

    Das, Sanjib; Keum, Jong Kahk; Browning, Jim; Gu, Gong; Yang, Bin; Do, Changwoo; Chen, Wei; Chen, Jihua; Ivanov, Ilia N; Hong, Kunlun; et al

    2015-07-16

    Advances in materials design and device engineering led to inverted organic solar cells (i-OSCs) with superior power conversion efficiencies (PCEs) to their conventional counterparts, in addition to the well-known better ambient stability. Despite the significant progress, however, it has so far been unclear how the morphologies of the photoactive layer and its interface with the cathode modifying layer impact device performance. Here, we report an in-depth morphology study of the i-OSC active and cathode modifying layers, employing a model system with the well-established bulk-heterojunction, PTB7:PC71BM as the active layer and poly-[(9,9-bis(3 -(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)] (PFN) as the cathode surface modifying layer. Wemore »have also identified the role of a processing additive, 1,8-diiodooctane (DIO), used in the spin-casting of the active layer to increase PCE. Using a variety of characterization techniques, we demonstrate that the high PCEs of i-OSCs are due to the smearing (diffusion) of electron-accepting PC71BM into the PFN layer, resulting in improved electron transport. The PC71BM diffusion occurs after spin-casting the active layer onto the PFN layer, when residual solvent molecules act as a plasticizer. The DIO additive, with a higher boiling point than the host solvent, has a longer residence time in the spin-cast active layer, resulting in more PC71BM smearing and therefore more efficient electron transport. This work provides important insight and guidance to further enhancement of i-OSC performance by materials and interface engineering.« less

  15. Correlating High Power Conversion Efficiency of PTB7:PC71BM Inverted Organic Solar Cells with Nanoscale Structures

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

    Das, Sanjib; Keum, Jong Kahk; Browning, Jim; Gu, Gong; Yang, Bin; Do, Changwoo; Chen, Wei; Chen, Jihua; Ivanov, Ilia N; Hong, Kunlun; et al

    2015-07-16

    Advances in materials design and device engineering led to inverted organic solar cells (i-OSCs) with superior power conversion efficiencies (PCEs) to their conventional counterparts, in addition to the well-known better ambient stability. Despite the significant progress, however, it has so far been unclear how the morphologies of the photoactive layer and its interface with the cathode modifying layer impact device performance. Here, we report an in-depth morphology study of the i-OSC active and cathode modifying layers, employing a model system with the well-established bulk-heterojunction, PTB7:PC71BM as the active layer and poly-[(9,9-bis(3 -(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)] (PFN) as the cathode surface modifying layer. Wemore »have also identified the role of a processing additive, 1,8-diiodooctane (DIO), used in the spin-casting of the active layer to increase PCE. Using a variety of characterization techniques, we demonstrate that the high PCEs of i-OSCs are due to the smearing (diffusion) of electron-accepting PC71BM into the PFN layer, resulting in improved electron transport. The PC71BM diffusion occurs after spin-casting the active layer onto the PFN layer, when residual solvent molecules act as a plasticizer. The DIO additive, with a higher boiling point than the host solvent, has a longer residence time in the spin-cast active layer, resulting in more PC71BM smearing and therefore more efficient electron transport. This work provides important insight and guidance to further enhancement of i-OSC performance by materials and interface engineering.« less

  16. The Flow of Power-Law Fluids in Axisymmetric Corrugated Tubes

    E-Print Network [OSTI]

    Sochi, Taha

    2010-01-01

    In this article we present an analytical method for deriving the relationship between the pressure drop and flow rate in laminar flow regimes, and apply it to the flow of power-law fluids through axially-symmetric corrugated tubes. The method, which is general with regards to fluid and tube shape within certain restrictions, can also be used as a foundation for numerical integration where analytical expressions are hard to obtain due to mathematical or practical complexities. Five converging-diverging geometries are used as examples to illustrate the application of this method.

  17. The Flow of Power-Law Fluids in Axisymmetric Corrugated Tubes

    E-Print Network [OSTI]

    Taha Sochi

    2010-06-13

    In this article we present an analytical method for deriving the relationship between the pressure drop and flow rate in laminar flow regimes, and apply it to the flow of power-law fluids through axially-symmetric corrugated tubes. The method, which is general with regards to fluid and tube shape within certain restrictions, can also be used as a foundation for numerical integration where analytical expressions are hard to obtain due to mathematical or practical complexities. Five converging-diverging geometries are used as examples to illustrate the application of this method.

  18. Near and far field models of external fluid mechanics of Ocean Thermal Energy Conversion (OTEC) power plants

    E-Print Network [OSTI]

    Rodríguez Buńo, Mariana

    2013-01-01

    The world is facing the challenge of finding new renewable sources of energy - first, in response to fossil fuel reserve depletion, and second, to reduce greenhouse gas emissions. Ocean Thermal Energy Conversion (OTEC) can ...

  19. Power Flow Management in a High Penetration Wind-Diesel Hybrid Power System with Short-Term Energy Storage

    SciTech Connect (OSTI)

    Drouilhet, S. M.

    1999-07-29

    This paper is intended as an introduction to some of the control challenges faced by developers of high penetration wind-diesel systems, with a focus on the management of power flows in order to achieve precise regulation of frequency and voltage in the face of rapidly varying wind power input and load conditions. The control algorithms presented herein are being implemented in the National Renewable Energy Laboratory (NREL) high penetration wind-diesel system controller that will be installed in the village of Wales, Alaska, in early 2000.

  20. Thermoelectric Conversion of Waste Heat to Electricity in an...

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

    Conversion of Waste Heat to Electricity in an IC Engine-Powered Vehicle Thermoelectric Conversion of Waste Heat to Electricity in an IC Engine Powered Vehicle...

  1. Distributed Multi-Period Optimal Power Flow for Demand Response in Microgrids

    E-Print Network [OSTI]

    Trumpf, Jochen

    Distributed Multi-Period Optimal Power Flow for Demand Response in Microgrids Paul Scott Methodologies]: Artificial Intelligence Keywords OPF; ADMM; demand response; distributed control; micro- grid-coupled behaviours. In this new regime demand response (DR) techniques will play a central role in providing

  2. Animation and Visualization of Spot Prices via Quadratized Power Flow Analysis

    E-Print Network [OSTI]

    Animation and Visualization of Spot Prices via Quadratized Power Flow Analysis A. P. Sakis@attbi.com Abstract This paper presents a new model for efficient calculation of spot prices and animation and visualization of spot price evolution as the system operating point is changing. The computational method

  3. Primary pump power as a measure of fluid density during bubbly two-phase flow. [PWR

    SciTech Connect (OSTI)

    McCreery, G.E.; Linebarger, J.H.; Koske, J.E.

    1983-01-01

    A nuclear plant operator requires other information on reactor coolant system inventory besides just pressurizer liquid level, which often disappears or gives ambiguous indications during a loss-of-coolant accident. Erroneous instrument readings during the Three Mile Island and Ginna accidents are examples. Pump power or current is shown in this paper to provide an additional source of inventory information. When the reactor coolant pumps are operating, it allows the operator to make decisions about the advisability of continued pump- and safety-injection operation. The inventory information is provided by a simple method of calculating fluid density for bubbly two-phase flow by relating pump power or current to fluid density. The calculational method is derived and compared with data in this paper. Calculations using the method agree well with the measured experimental data with increasing void fraction, until the flow transitions from bubbly to partially stratified churn flow within the pump.

  4. HHFW Power Flow Along Magnetic Field Lines In The Scrape-off Layer of NSTX

    SciTech Connect (OSTI)

    Rory Perkins, et. al.

    2012-02-27

    A significant fraction of high-harmonic fast-wave (HHFW) power applied to NSTX can be lost to the scrape-off layer (SOL) and deposited in bright and hot spirals on the divertor rather than in the core plasma. We show that the HHFW power flows to these spirals along magnetic field lines passing through the SOL in front of the antenna, implying that the HHFW power couples across the entire width of the SOL rather than mostly at the antenna face. This result will help guide future efforts to understand and minimize these edge losses in order to maximize fast wave heating and current drive.

  5. A Merged two-stage power conversion architecture with switched capacitor circuit for an LED driver module

    E-Print Network [OSTI]

    Lim, Seungbum

    2012-01-01

    In a power converter specified to convert from wide-range and high-level DC voltage or AC line voltage to low-level DC voltage, satisfying high efficiency, high power density, and high power factor is challenging because ...

  6. Chance Constrained Optimal Power Flow: Risk-Aware Network Control under Uncertainty

    E-Print Network [OSTI]

    Bienstock, Daniel; Harnett, Sean

    2012-01-01

    When uncontrollable resources fluctuate, Optimum Power Flow (OPF), routinely used by the electric power industry to re-dispatch hourly controllable generation (coal, gas and hydro plants) over control areas of transmission networks, can result in grid instability, and, potentially, cascading outages. This risk arises because OPF dispatch is computed without awareness of major uncertainty, in particular fluctuations in renewable output. As a result, grid operation under OPF with renewable variability can lead to frequent conditions where power line flow ratings are significantly exceeded. Such a condition, which is borne by simulations of real grids, would likely resulting in automatic line tripping to protect lines from thermal stress, a risky and undesirable outcome which compromises stability. Smart grid goals include a commitment to large penetration of highly fluctuating renewables, thus calling to reconsider current practices, in particular the use of standard OPF. Our Chance Constrained (CC) OPF correct...

  7. IEEE TRANSACTIONS ON ENERGY CONVERSION, VOL. 24, NO. 1, MARCH 2009 125 Short-Term Prediction of Wind Farm Power

    E-Print Network [OSTI]

    Kusiak, Andrew

    IEEE TRANSACTIONS ON ENERGY CONVERSION, VOL. 24, NO. 1, MARCH 2009 125 Short-Term Prediction into a large-scale industry. As most wind farms are relatively new, it is natural that their performance has 13, 2009; current version published February 19, 2009. This work was supported by Iowa Energy Center

  8. Outage Detection in Power Distribution Networks with Optimally-Deployed Power Flow Sensors

    E-Print Network [OSTI]

    Zhao, Yue

    distribution networks. As society becomes more dependent on electric power, the economic and societal costs due sensor at the substation [2]. In networks This research was supported in part by the DTRA under Grant a single digital transient recording device at the substation, fault location and diagnosis systems have

  9. Research Reactor Conversion | National Nuclear Security Administration

    National Nuclear Security Administration (NNSA)

    Reactor Conversion | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing Proliferation Powering the...

  10. Plant Design and Cost Assessment of Forced Circulation Lead-Bismuth Cooled Reactor with Conventional Power Conversion Cycles

    E-Print Network [OSTI]

    Dostal, Vaclav

    Cost of electricity is the key factor that determines competitiveness of a power plant. Thus the proper selection, design and optimization of the electric power generating cycle is of main importance. This report makes an ...

  11. Architectures and circuits for low-voltage energy conversion and applications in renewable energy and power management

    E-Print Network [OSTI]

    Pilawa-Podgurski, Robert C. N

    2012-01-01

    In this thesis we seek to develop smaller, less expensive, and more efficient power electronics. We also investigate emerging applications where the proper implementation of these new types of power converters can have a ...

  12. Flow simulation of the Component Development Integration Facility magnetohydrodynamic power train system

    SciTech Connect (OSTI)

    Chang, S.L.; Lottes, S.A.; Bouillard, J.X.; Petrick, M.

    1997-11-01

    This report covers application of Argonne National Laboratory`s (ANL`s) computer codes to simulation and analysis of components of the magnetohydrodynamic (MHD) power train system at the Component Development and Integration Facility (CDIF). Major components of the system include a 50-MWt coal-fired, two-stage combustor and an MHD channel. The combustor, designed and built by TRW, includes a deswirl section between the first and the second-stage combustor and a converging nozzle following the second-stage combustor, which connects to the MHD channel. ANL used computer codes to simulate and analyze flow characteristics in various components of the MHD system. The first-stage swirl combustor was deemed a mature technology and, therefore, was not included in the computer simulation. Several versions of the ICOMFLO computer code were used for the deswirl section and second-stage combustor. The MGMHD code, upgraded with a slag current leakage submodel, was used for the MHD channel. Whenever possible data from the test facilities were used to aid in calibrating parameters in the computer code, to validate the computer code, or to set base-case operating conditions for computations with the computer code. Extensive sensitivity and parametric studies were done on cold-flow mixing in the second-stage combustor, reacting flow in the second-stage combustor and converging nozzle, and particle-laden flow in the deswirl zone of the first-stage combustor, the second-stage combustor, and the converging nozzle. These simulations with subsequent analysis were able to show clearly in flow patterns and various computable measures of performance a number of sensitive and problematical areas in the design of the power train. The simulations of upstream components also provided inlet parameter profiles for simulation of the MHD power generating channel. 86 figs., 18 tabs.

  13. 1112 IEEE TRANSACTIONS ON ENERGY CONVERSION, VOL. 25, NO. 4, DECEMBER 2010 Short-Horizon Prediction of Wind Power

    E-Print Network [OSTI]

    Kusiak, Andrew

    of Wind Power: A Data-Driven Approach Andrew Kusiak, Member, IEEE, and Zijun Zhang Abstract--This paper discusses short-horizon prediction of wind speed and power using wind turbine data collected at 10 s inter and data-driven models are developed for wind prediction. Power prediction models are estab- lished, which

  14. Engineering Predictions in Industrial and Power Flows Using the Retrograde Condensation Curve. Part I-Methodology

    E-Print Network [OSTI]

    Labinov, Mark S

    2014-01-01

    Industrial and power systems rely on engineering predictions of the flow properties of working fluids. The paper proposes a way of the utilization of the vapor quality values along the new retrograde condensation curve in the generation of the void fraction design guidelines and reliable prediction of the saturated liquid specific volumes/densities. The new procedure eliminates the involvement of semi-empirical relationships like rectilinear diameter and other similar models.

  15. Numerical Simulation of the Flow of a Power Law Fluid in an Elbow Bend 

    E-Print Network [OSTI]

    Kanakamedala, Karthik

    2010-07-14

    equations are given by, ????? = ????? + ?? + ??? where, ? is the Laplacian operator ? is the density of the body ? is the body force ? is the velocity vector However, the fluid being dealt within the problem is a non-Newtonian power law fluid... parameters. This problem finds applications mainly in the food and polymer industries where non-Newtonian fluids flow through different piping sections. The elbow geometry used for performing the simulations consists of a straight portion of ??? both after...

  16. Transverse flowing liquid Kerr cell for high average power laser Q-switching and for direct modulation of high power laser beams.

    DOE Patents [OSTI]

    Comaskey, Brian J.

    2004-12-07

    A fluid flow concept is applied in an optical apparatus to define a high gain stand-off, fast electro-optical q-switch which is highly impervious to high average power optical loads.

  17. Study of multi-phase flow characteristics in an MHD power train

    SciTech Connect (OSTI)

    Chang, S.L.; Lottes, S.A.; Bouillard, J.X.; Petrick, M.

    1993-08-01

    Computer simulation was used to predict two-phase flow processes in the CDIF MHD power train system. The predictions were used to evaluate the effects of operating and design parameters on the performance of the system and a parametric evaluation provides information to enhance the performance of the system. Major components of the system under investigation are the two-stage combustor, the converging/diverging nozzle, the supersonic MHD channel, and the diffuser. Flow in each component was simulated using a computer code. Integrating the computer codes, the two-phase flow processes in the system was calculated. Recently, the computer codes were used to investigate problems of nozzle erosion and the non-uniform iron oxide coverage on the cathode wall in the channel. A limited parametric study was conducted. The results indicated that (1) among the three nozzle geometries under investigation a {number_sign}5 nozzle has the smoothest flow development in the nozzle and has the lowest droplet deposition on wall and (2) smaller particle size and lower injection velocity tend to disperse the iron oxide particles more uniformly in the nozzle.

  18. Estimation of steady-state and transcient power distributions for the RELAP analyses of the 1963 loss-of-flow and loss-of-pressure tests at BR2.

    SciTech Connect (OSTI)

    Dionne, B.; Tzanos, C. P.

    2011-05-23

    To support the safety analyses required for the conversion of the Belgian Reactor 2 (BR2) from highly-enriched uranium (HEU) to low-enriched uranium (LEU) fuel, the simulation of a number of loss-of-flow tests, with or without loss of pressure, has been undertaken. These tests were performed at BR2 in 1963 and used instrumented fuel assemblies (FAs) with thermocouples (TC) imbedded in the cladding as well as probes to measure the FAs power on the basis of their coolant temperature rise. The availability of experimental data for these tests offers an opportunity to better establish the credibility of the RELAP5-3D model and methodology used in the conversion analysis. In order to support the HEU to LEU conversion safety analyses of the BR2 reactor, RELAP simulations of a number of loss-of-flow/loss-of-pressure tests have been undertaken. Preliminary analyses showed that the conservative power distributions used historically in the BR2 RELAP model resulted in a significant overestimation of the peak cladding temperature during the transient. Therefore, it was concluded that better estimates of the steady-state and decay power distributions were needed to accurately predict the cladding temperatures measured during the tests and establish the credibility of the RELAP model and methodology. The new approach ('best estimate' methodology) uses the MCNP5, ORIGEN-2 and BERYL codes to obtain steady-state and decay power distributions for the BR2 core during the tests A/400/1, C/600/3 and F/400/1. This methodology can be easily extended to simulate any BR2 core configuration. Comparisons with measured peak cladding temperatures showed a much better agreement when power distributions obtained with the new methodology are used.

  19. The flow of power law fluids in elastic networks and porous media

    E-Print Network [OSTI]

    Sochi, Taha

    2015-01-01

    The flow of power law fluids, which include shear thinning and shear thickening as well as Newtonian as a special case, in networks of interconnected elastic tubes is investigated using a residual based pore scale network modeling method with the employment of newly derived formulae. Two relations describing the mechanical interaction between the local pressure and local cross sectional area in distensible tubes of elastic nature are considered in the derivation of these formulae. The model can be used to describe shear dependent flows of mainly viscous nature. The behavior of the proposed model is vindicated by several tests in a number of special and limiting cases where the results can be verified quantitatively or qualitatively. The model, which is the first of its kind, incorporates more than one major non-linearity corresponding to the fluid rheology and conduit mechanical properties, that is non-Newtonian effects and tube distensibility. The formulation, implementation and performance indicate that the...

  20. Wind energy conversion system

    DOE Patents [OSTI]

    Longrigg, Paul (Golden, CO)

    1987-01-01

    The wind energy conversion system includes a wind machine having a propeller connected to a generator of electric power, the propeller rotating the generator in response to force of an incident wind. The generator converts the power of the wind to electric power for use by an electric load. Circuitry for varying the duty factor of the generator output power is connected between the generator and the load to thereby alter a loading of the generator and the propeller by the electric load. Wind speed is sensed electro-optically to provide data of wind speed upwind of the propeller, to thereby permit tip speed ratio circuitry to operate the power control circuitry and thereby optimize the tip speed ratio by varying the loading of the propeller. Accordingly, the efficiency of the wind energy conversion system is maximized.

  1. Voltage Collapse and ODE Approach to Power Flows: Analysis of a Feeder Line with Static Disorder in Consumption/Production

    E-Print Network [OSTI]

    Chertkov, M; Turtisyn, K; Chernyak, V; Lebedev, V

    2011-01-01

    We consider a model of a distribution feeder connecting multiple loads to the sub-station. Voltage is controlled directly at the head of the line (sub-station), however, voltage anywhere further down the line is subject to fluctuations, caused by irregularities of real and reactive distributed power consumption/generation. The lack of a direct control of voltage along the line may result in the voltage instability, also called voltage collapse - phenomenon well known and documented in the power engineering literature. Motivated by emerging photo-voltaic technology, which brings a new source of renewable generation but also contributes significant increase in power flow fluctuations, we reexamine the phenomenon of voltage stability and collapse. In the limit where the number of consumers is large and spatial variations in power flows are smooth functions of position along the feeder, we derive a set of the power flow Ordinary Differential Equations (ODE), verify phenomenon of voltage collapse, and study the ef...

  2. AVTA: Vehicle to Grid Power Flow Regulations and Building Codes Review

    Broader source: Energy.gov [DOE]

    The Vehicle Technologies Office's Advanced Vehicle Testing Activity carries out testing on a wide range of advanced vehicles and technologies on dynamometers, closed test tracks, and on-the-road. These results provide benchmark data that researchers can use to develop technology models and guide future research and development. The following report is a review of Vehicle-to-Grid power flow regulations and building codes, as informed by the AVTA's testing on plug-in electric vehicle charging equipment. This research was conducted by Idaho National Laboratory.

  3. Electron Transfer Dynamics in Photocatalytic CO2 Conversion ...

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

    Electron Transfer Dynamics in Photocatalytic CO2 Conversion Electron Transfer Dynamics in Photocatalytic CO2 Conversion Coal is the workhorse of our power industry, responsible for...

  4. The Coordinated Control of a Central Air Conditioning System Based on Variable Chilled Water Temperature and Variable Chilled Water Flow 

    E-Print Network [OSTI]

    Liu, J.; Mai, Y.; Liu, X.

    2006-01-01

    At present, regulation of water flow by means of pump frequency conversion is one of the major methods for power-saving in central air conditioning systems. In this article, optimization regulation for central air conditioning system on the basis...

  5. Sandia Energy - Conventional Water Power: Technology Development

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

    Technology Development Home Stationary Power Energy Conversion Efficiency Water Power Conventional Water Power: Technology Development Conventional Water Power: Technology...

  6. Electrokinetic Power Generation from Liquid Water Microjets

    SciTech Connect (OSTI)

    Duffin, Andrew M.; Saykally, Richard J.

    2008-02-15

    Although electrokinetic effects are not new, only recently have they been investigated for possible use in energy conversion devices. We have recently reported the electrokinetic generation of molecular hydrogen from rapidly flowing liquid water microjets [Duffin et al. JPCC 2007, 111, 12031]. Here, we describe the use of liquid water microjets for direct conversion of electrokinetic energy to electrical power. Previous studies of electrokinetic power production have reported low efficiencies ({approx}3%), limited by back conduction of ions at the surface and in the bulk liquid. Liquid microjets eliminate energy dissipation due to back conduction and, measuring only at the jet target, yield conversion efficiencies exceeding 10%.

  7. Formation of a laminar electron flow for 300 GHz high-power pulsed gyrotron

    SciTech Connect (OSTI)

    Yamaguchi, Yuusuke; Tatematsu, Yoshinori; Saito, Teruo; Ikeda, Ryosuke; Mudiganti, Jagadish C.; Ogawa, Isamu; Idehara, Toshitaka [Research Center for Development of Far-Infrared Region, University of Fukui, 3-9-1 Bunkyo, Fukui-shi 910-8507 (Japan)

    2012-11-15

    This paper describes the design of a triode magnetron injection gun for use in a 200 kW, 300 GHz gyrotron. As power and frequency increase, the performance of the gyrotron becomes quite sensitive to the quality of the electron beam. Formation of a laminar electron flow is essential for the realization of a high quality beam with a small velocity spread. In this study, a new method is developed for a quantitative evaluation of the laminarity and is applied to optimize the electrode design. The laminarity depends not only on conventional design parameters such as the cathode slant angle but also on the spatial distribution of the electric field along the beam trajectory. In the optimized design, the velocity pitch factors, {alpha}, larger than 1.2 are obtained at 65 kV, 10 A with spreads, {Delta}{alpha}, less than 5%.

  8. 1462 IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 26, NO. 3, AUGUST 2011 A Self-Organizing Strategy for Power Flow Control

    E-Print Network [OSTI]

    Qu, Zhihua

    for Power Flow Control of Photovoltaic Generators in a Distribution Network Huanhai Xin, Zhihua Qu, Fellow 310027, China. He was also with the University of Central Florida, Orlando, FL 32815 USA, when he and Computer Sci- ence, University of Central Florida, Orlando, FL 32815 USA (e-mail: qu@eecs. ucf.edu). J

  9. Simulation of three-dimensional multi-phase flow characteristics in the deswirl section of the CDIF MHD power train

    SciTech Connect (OSTI)

    Chang, S.L.; Lottes, S.A.; Petrick, M.

    1994-06-01

    A three-dimensional, two-phase, turbulent flow computer code was used to predict flow characteristics of seed particles and coal gas in the deswirl section of the CDIF MHD power train system. Seed material which has a great effect on the overall performance of the MHD system is injected in the deswirl against the swirling coal gas flow coming from the first stage combustor. While testing the MHD system, excessive seed material (70% more than theoretical value) was required to achieve design operating conditions. Calculations show that the swirling coal gas flow turns a 90 degree angle to minimize the swirl motion before entering a second stage combustor and many seed particles are too slow to react to the flow turning and deposit on the walls of the deswirl section. Some seed material deposited on the walls is covered by slag layer and removed from the gas flow. The reduction of seed material in the gas flow decreases MHD power generation significantly. A computational experiment was conducted and its results show that seed injection on the wall can be minimized by simply changing the seed injection and an optimum location was identified. If seed is injected from the location of choice, the seed deposition is reduced by a factor of 10 compared to the original case.

  10. Influence of fluid density on the statistics of power fluctuations in von K\\'arm\\'an swirling flows

    E-Print Network [OSTI]

    Opazo, A; Bustamante, G; Labbé, R

    2015-01-01

    We report experimental results for fluctuations of injected power in confined von K\\'arm\\'an swirling flows with constant external torque applied to the stirrers. Two experiments were performed at nearly equal Reynolds numbers in geometrically similar experimental setups, using air in one of them and water in the other. We found that the probability density function of power fluctuations is strongly asymmetric in air, while in water it is closer to a Gaussian, showing that the effect that a big change on the fluid density has on the flow-stirrer interaction is not reflected merely by a change in the amplitude of stirrers' response. In the case of water, with a density roughly 830 times greater than air density, the forcing exerted by the flow on the stirrers is stronger, so that they follow more closely the locally averaged rotation of the flow. When the fluid is air, the forcing is much weaker, resulting not only in a smaller stirrer response to the torque exerted by the flow, but also in power fluctuations ...

  11. emission in galaxies at z1-2: Evidence for cold flow accretion powered star formation in the

    E-Print Network [OSTI]

    Spoon, Henrik

    PDRs, extending to kpc scales. We suggest that the star formation mode in these systems follows to the observed [CII] line. Subject headings: galaxies: evolution, star formation, PDRs, PAHs, shocks #12;­ 3 ­ 1Strong C+ emission in galaxies at z1-2: Evidence for cold flow accretion powered star formation

  12. Journal of Power Sources xxx (2006) xxxxxx The impact of channel path length on PEMFC flow-field design

    E-Print Network [OSTI]

    Van Zee, John W.

    2006-01-01

    Journal of Power Sources xxx (2006) xxx­xxx The impact of channel path length on PEMFC flow Distributions in reactant species concentration in a PEMFC due to local consumption of fuel and local transport in three dimensions in a PEMFC. These distributions can lead to flooding or drying of the membrane that may

  13. Biogeography-Based Optimization and the Solution of the Power Flow Problem

    E-Print Network [OSTI]

    Simon, Dan

    engineer Jules Carpentier [7]. A power utility may own power generating plants fueled by coal, natural gas

  14. Ocean energy conversion systems annual research report

    SciTech Connect (OSTI)

    Not Available

    1981-03-01

    Alternative power cycle concepts to the closed-cycle Rankine are evaluated and those that show potential for delivering power in a cost-effective and environmentally acceptable fashion are explored. Concepts are classified according to the ocean energy resource: thermal, waves, currents, and salinity gradient. Research projects have been funded and reported in each of these areas. The lift of seawater entrained in a vertical steam flow can provide potential energy for a conventional hydraulic turbine conversion system. Quantification of the process and assessment of potential costs must be completed to support concept evaluation. Exploratory development is being completed in thermoelectricity and 2-phase nozzles for other thermal concepts. Wave energy concepts are being evaluated by analysis and model testing with present emphasis on pneumatic turbines and wave focussing. Likewise, several conversion approaches to ocean current energy are being evaluated. The use of salinity resources requires further research in membranes or the development of membraneless processes. Using the thermal resource in a Claude cycle process as a power converter is promising, and a program of R and D and subsystem development has been initiated to provide confirmation of the preliminary conclusion.

  15. Quantum conversion

    E-Print Network [OSTI]

    Michael Mazilu

    2015-08-06

    The electromagnetic momentum transferred transfered to scattering particles is proportional to the intensity of the incident fields, however, the momentum of single photons ($\\hbar k$) does not naturally appear in these classical expressions. Here, we discuss an alternative to Maxwell's stress tensor that renders the classical electromagnetic field momentum compatible to the quantum mechanical one. This is achieved through the introduction of the quantum conversion which allows the transformation, including units, of the classical fields to wave-function equivalent fields.

  16. Interactions between turbulent open channel flow, power and the wake of an axial-flow marine turbine

    E-Print Network [OSTI]

    Siefert, Chris

    turbine Leonardo P. Chamorro1 , Craig Hill1 , Vincent Neary2 , Budi Gunawan2 , Roger Arndt1 , Fotis-flow marine hydrokinetic turbines was lacking. Advancing this area of knowledge within the field of marine and hydrokinetic energy research, development, and deployment will lead to more efficient turbine operations

  17. High-Harmonic Fast-Wave Power Flow Along Magnetic Field Lines in the Scrape-Off Layer of NSTX

    SciTech Connect (OSTI)

    Perkins, R. J. [Princeton Plasma Physics Laboratory (PPPL); Hosea, J. [Princeton Plasma Physics Laboratory (PPPL); Kramer, G. [Princeton Plasma Physics Laboratory (PPPL); Ahn, Joonwook [ORNL; Bell, R. E. [Princeton Plasma Physics Laboratory (PPPL); Diallo, A. [Princeton Plasma Physics Laboratory (PPPL); Gerhardt, S. [Princeton Plasma Physics Laboratory (PPPL); Gray, T. K. [Oak Ridge National Laboratory (ORNL); Green, David L [ORNL; Jaeger, Erwin Frederick [ORNL; Jaworski, M. A. [Princeton Plasma Physics Laboratory (PPPL); LeBlanc, B [Princeton Plasma Physics Laboratory (PPPL); McLean, Adam G [ORNL; Maingi, Rajesh [ORNL; Phillips, C. K. [Princeton Plasma Physics Laboratory (PPPL); Roquemore, L. [Princeton Plasma Physics Laboratory (PPPL); Ryan, Philip Michael [ORNL; Sabbagh, S. A. [Columbia University; Taylor, G. [Princeton Plasma Physics Laboratory (PPPL); Wilson, J. R. [Princeton Plasma Physics Laboratory (PPPL)

    2012-01-01

    A significant fraction of high-harmonic fast-wave (HHFW) power applied to NSTX can be lost to the scrape-off layer (SOL) and deposited in bright and hot spirals on the divertor rather than in the core plasma. We show that the HHFW power flows to these spirals along magnetic field lines passing through the SOL in front of the antenna, implying that the HHFW power couples across the entire width of the SOL rather than mostly at the antenna face. This result will help guide future efforts to understand and minimize these edge losses in order to maximize fast-wave heating and current drive.

  18. Suction-recirculation device for stabilizing particle flows within a solar powered solid particle receiver

    DOE Patents [OSTI]

    Kolb, Gregory J. (Albuquerque, NM)

    2012-02-07

    A suction-recirculation device for stabilizing the flow of a curtain of blackened heat absorption particles falling inside of a solar receiver with an open aperture. The curtain of particles absorbs the concentrated heat from a solar mirror array reflected up to the receiver on a solar power tower. External winds entering the receiver at an oblique angle can destabilize the particle curtain and eject particles. A fan and ductwork is located behind the back wall of the receiver and sucks air out through an array of small holes in the back wall. Any entrained particles are separated out by a conventional cyclone device. Then, the air is recirculated back to the top of the receiver by injecting the recycled air through an array of small holes in the receiver's ceiling and upper aperture front wall. Since internal air is recirculated, heat losses are minimized and high receiver efficiency is maintained. Suction-recirculation velocities in the range of 1-5 m/s are sufficient to stabilize the particle curtain against external wind speeds in excess of 10 m/s.

  19. Power plant degradation : a modular secondary plant and integral flow accelerated corrosion model

    E-Print Network [OSTI]

    Van der Helm, Mark Johan, 1972-

    2001-01-01

    Flow Accelerated Corrosion (FAC) is the most prevalent material degradation mechanism for low carbon steel in steam-water flow systems. The band of uncertainty in predictions of wear rate due to FAC spans one to two orders ...

  20. Cornell's conversion of a coal fired heating plant to natural Gas -BACKGROUND: In December 2009, the Combined Heat and Power Plant

    E-Print Network [OSTI]

    Keinan, Alon

    Cornell's conversion of a coal fired heating plant to natural Gas University began operating with natural gas, instead of the coal-fired generators of the coal that had been stockpiled, the Plant is running completely on natural gas

  1. Thin power law film flow down an inclined plane: consistent shallow water models and stability under large scale perturbations

    E-Print Network [OSTI]

    Noble, Pascal

    2012-01-01

    In this paper we derive consistent shallow water equations for thin films of power law fluids down an incline. These models account for the streamwise diffusion of momentum which is important to describe accurately the full dynamic of the thin film flows when instabilities like roll-waves arise. These models are validated through a comparison with Orr Sommerfeld equations for large scale perturbations. We only consider laminar flow for which the boundary layer issued from the interaction of the flow with the bottom surface has an influence all over the transverse direction to the flow. In this case the concept itself of thin film and its relation with long wave asymptotic leads naturally to flow conditions around a uniform free surface Poiseuille flow. The apparent viscosity diverges at the free surface which, in turn, introduces a singularity in the formulation of the Orr-Sommerfeld equations and in the derivation of shallow water models. We remove this singularity by introducing a weaker formulation of Cauc...

  2. Power dissipation and time-averaged pressure in oscillating flow through a sudden area change

    E-Print Network [OSTI]

    Smith, Barton L.

    that abrupt changes in geometry are ubiquitous in Stirling engines, thermoacoustics, and res- piratory flows Barton L. Smith Mechanical and Aerospace Engineering Department, Utah State University, Logan, Utah 84322-averaged pressure gradient has been used to counteract streaming flows in a thermoacoustic Stirling refrigerator1

  3. Study of Power Converter Topologies with Energy Recovery and grid power flow control Part B: boost converter with energy storage

    E-Print Network [OSTI]

    Rogelio, Garcia Retegui; Gustavo, Uicich; Mario, Benedetti; Gilles, Le Godec; Konstantinos, Papastergiou

    2015-01-01

    In the framework of a Transfer line (TT2) Consolidation Programme, a number of studies on Energy cycling have been commissioned. Part of this work involves the study of dierent power electronic system topologies for magnet energy recovery. In this report, the use of a boost front-end converter supplying DC link of a 4-quadrant magnet supply is analysed. The key objective of the study is to find control strategies that result in the control of the peak power required from the power network as well as to recover the magnet energy into capacitor banks with controlled voltage fluctuation. The study comprises the modelling of the system by means of the method of state averaging and the development of regulation strategies to energy management. The proposed control strategies can be divided in two groups: in the first group, the magnet current is used to define the reference for the control system, while in the second group this current is unknown and some strategies are devised to limit the power drawn from the el...

  4. Biomass Thermochemical Conversion Program: 1986 annual report

    SciTech Connect (OSTI)

    Schiefelbein, G.F.; Stevens, D.J.; Gerber, M.A.

    1987-01-01

    Wood and crop residues constitute a vast majority of the biomass feedstocks available for conversion, and thermochemical processes are well suited for conversion of these materials. Thermochemical conversion processes can generate a variety of products such as gasoline hydrocarbon fuels, natural gas substitutes, or heat energy for electric power generation. The US Department of Energy is sponsoring research on biomass conversion technologies through its Biomass Thermochemical Conversion Program. Pacific Northwest Laboratory has been designated the Technical Field Management Office for the Biomass Thermochemical Conversion Program with overall responsibility for the Program. This report briefly describes the Thermochemical Conversion Program structure and summarizes the activities and major accomplishments during fiscal year 1986. 88 refs., 31 figs., 5 tabs.

  5. Optimal power flow application issues in the Pool paradigm George Grossa,*, Ettore Bompardb

    E-Print Network [OSTI]

    Gross, George

    a Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Power ramifications. These factors have wide ranging economic impacts, whose implications are very pronounced due consideration of some system performance measures into the steady state analysis of the power system. The basic

  6. 3. Energy conversion, balances, efficiency, equilibrium

    E-Print Network [OSTI]

    Zevenhoven, Ron

    1/124 3. Energy conversion, balances, efficiency, equilibrium (Introduction to Thermodynamics) Ron and Flow Engineering | 20500 Turku | Finland 2/124 3.1: Energy Ĺbo Akademi University | Thermal and Flow Engineering | 20500 Turku | Finland #12;3/124 What is energy? /1 "Energy is any quantity that changes

  7. The effect of expansion-ratio limitations on positive-displacement, total-flow geothermal power systems

    SciTech Connect (OSTI)

    DiPippo, R.

    1982-02-01

    Combined steam-turbine/positive-displacement engine (PDE) geothermal power systems are analyzed thermodynamically and compared with optimized reference flash-steam plants. Three different configurations of combined systems are considered. Treated separately are the cases of self-flowing and pumped wells. Two strategies are investigated that help overcome the inherent expansion-ratio limitation of PDE's: pre-flashing and pre-mixing. Parametrically-obtained results show the required minimum PDE efficiency for the combined system to match the reference plant for various sets of design conditions.

  8. Conversion of Questionnaire Data

    SciTech Connect (OSTI)

    Powell, Danny H; Elwood Jr, Robert H

    2011-01-01

    During the survey, respondents are asked to provide qualitative answers (well, adequate, needs improvement) on how well material control and accountability (MC&A) functions are being performed. These responses can be used to develop failure probabilities for basic events performed during routine operation of the MC&A systems. The failure frequencies for individual events may be used to estimate total system effectiveness using a fault tree in a probabilistic risk analysis (PRA). Numeric risk values are required for the PRA fault tree calculations that are performed to evaluate system effectiveness. So, the performance ratings in the questionnaire must be converted to relative risk values for all of the basic MC&A tasks performed in the facility. If a specific material protection, control, and accountability (MPC&A) task is being performed at the 'perfect' level, the task is considered to have a near zero risk of failure. If the task is performed at a less than perfect level, the deficiency in performance represents some risk of failure for the event. As the degree of deficiency in performance increases, the risk of failure increases. If a task that should be performed is not being performed, that task is in a state of failure. The failure probabilities of all basic events contribute to the total system risk. Conversion of questionnaire MPC&A system performance data to numeric values is a separate function from the process of completing the questionnaire. When specific questions in the questionnaire are answered, the focus is on correctly assessing and reporting, in an adjectival manner, the actual performance of the related MC&A function. Prior to conversion, consideration should not be given to the numeric value that will be assigned during the conversion process. In the conversion process, adjectival responses to questions on system performance are quantified based on a log normal scale typically used in human error analysis (see A.D. Swain and H.E. Guttmann, 'Handbook of Human Reliability Analysis with Emphasis on Nuclear Power Plant Applications,' NUREG/CR-1278). This conversion produces the basic event risk of failure values required for the fault tree calculations. The fault tree is a deductive logic structure that corresponds to the operational nuclear MC&A system at a nuclear facility. The conventional Delphi process is a time-honored approach commonly used in the risk assessment field to extract numerical values for the failure rates of actions or activities when statistically significant data is absent.

  9. Suction recirculation and its effects upon axial-flow pump power consumption 

    E-Print Network [OSTI]

    Prince, Tony M.

    1983-01-01

    1 Test Procedure Outline 2 Section and Pump Critical Flowrates and Speeds. 63 91 3 Power Coefficient and Reynolds Number Based on Cone Radius. 100 4 Power Coefficient and Reynolds Number Based on Surface Area. 101 5 Power Coefficient... Variation with NPSH with Q rl 54 Head Variation with NPSH with Q 2 . r2 55 Head Variation with NPSH with Q 3. r3' 120 128 129 130 131 134 135 136 CHAPTER I INTRODUCTION Pumps of different types are used to displace liquids from one location...

  10. Fast-wave Power Flow Along SOL Field Lines In NSTX nd The Associated Power Deposition Profile Across The SOL In Front Of The Antenna

    SciTech Connect (OSTI)

    Perkins, Roy

    2013-06-21

    Fast-wave heating and current drive efficiencies can be reduced by a number of processes in the vicinity of the antenna and in the scrape off layer (SOL). On NSTX from around 25% to more than 60% of the high-harmonic fast-wave power can be lost to the SOL regions, and a large part of this lost power flows along SOL magnetic field lines and is deposited in bright spirals on the divertor floor and ceiling. We show that field-line mapping matches the location of heat deposition on the lower divertor, albeit with a portion of the heat outside of the predictions. The field-line mapping can then be used to partially reconstruct the profile of lost fast-wave power at the midplane in front of the antenna, and the losses peak close to the last closed flux surface (LCFS) as well as the antenna. This profile suggests a radial standing-wave pattern formed by fast-wave propagation in the SOL, and this hypothesis will be tested on NSTX-U. Advanced RF codes must reproduce these results so that such codes can be used to understand this edge loss and to minimize RF heat deposition and erosion in the divertor region on ITER.

  11. Control strategies for 2-quadrant converter used in grid power flow control

    E-Print Network [OSTI]

    Maestri, Sebastian; Uicich, Gustavo; Benedetti, Mario; Papastergiou, Konstantinos; Le Godec, Gilles

    2015-01-01

    This work presents the analysis of a two-quadrant regulator connected to the DC-link of a 4-quadrant magnet supply. The key objective is to present some regulation strategies for controlling the peak power required from the power network as well as to recover the magnet energy into capacitor banks. A comparative study that highlights the trade off between the size of reactive elements, and the peak current drawn from the electrical network is presented.

  12. ME 533: Energy Conversion Emily M Ryan

    E-Print Network [OSTI]

    aspects of modern energy conversion systems, including traditional systems such as steam power plants, gas turbines and internal combustion engines and refrigeration systems, and renewable systems such as solar

  13. Sandia Energy - Conventional Water Power: Market Acceleration

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

    Market Acceleration Home Stationary Power Energy Conversion Efficiency Water Power Conventional Water Power: Market Acceleration Conventional Water Power: Market AccelerationTara...

  14. Power Systems Engineer | Princeton Plasma Physics Lab

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

    technical support and assistance on complicated Power System electrical, electronic and control systems. Knowledge of AC Power, power conversion, DC circuits, motors, power...

  15. Energy conversion system

    DOE Patents [OSTI]

    Murphy, L.M.

    1985-09-16

    The energy conversion system includes a photo-voltaic array for receiving solar radiation and converting such radiation to electrical energy. The photo-voltaic array is mounted on a stretched membrane that is held by a frame. Tracking means for orienting the photo-voltaic array in predetermined positions that provide optimal exposure to solar radiation cooperate with the frame. An enclosure formed of a radiation transmissible material includes an inside containment space that accommodates the photo-voltaic array on the stretched membrane, the frame and the tracking means, and forms a protective shield for all such components. The enclosure is preferably formed of a flexible inflatable material and maintains its preferred form, such as a dome, under the influence of a low air pressure furnished to the dome. Under this arrangement the energy conversion system is streamlined for minimizing wind resistance, sufficiently weathproof for providing protection against weather hazards such as hail, capable of using diffused light, lightweight for low-cost construction and operational with a minimal power draw.

  16. Energy conversion system

    DOE Patents [OSTI]

    Murphy, Lawrence M. (Lakewood, CO)

    1987-01-01

    The energy conversion system includes a photo-voltaic array for receiving solar radiation and converting such radiation to electrical energy. The photo-voltaic array is mounted on a stretched membrane that is held by a frame. Tracking means for orienting the photo-voltaic array in predetermined positions that provide optimal exposure to solar radiation cooperate with the frame. An enclosure formed of a radiation transmissible material includes an inside containment space that accommodates the photo-voltaic array on the stretched membrane, the frame and the tracking means, and forms a protective shield for all such components. The enclosure is preferably formed of a flexible inflatable material and maintains its preferred form, such as a dome, under the influence of a low air pressure furnished to the dome. Under this arrangement the energy conversion system is streamlined for minimizing wind resistance, sufficiently weatherproof for providing protection against weather hazards such as hail, capable of using diffused light, lightweight for low-cost construction, and operational with a minimal power draw.

  17. Large amplitude oscillatory shear flow of gluten dough: A model power-law gel

    E-Print Network [OSTI]

    Ng, Trevor S. K.

    In a previous paper [T. S. K. Ng and G. H. McKinley, J. Rheol.52(2), 417–449 (2008)], we demonstrated that gluten gels can best be understood as a polymericnetwork with a power-law frequency response that reflects the ...

  18. Gyroharmonic conversion experiments

    SciTech Connect (OSTI)

    Hirshfield, J.L.; LaPointe, M.A.; Ganguly, A.K. [Omega-P, Inc., New Haven, Connecticut 06520 (United States); LaPointe, M.A. [Yale University, New Haven, Connecticut 06511 (United States)

    1999-05-01

    Generation of high power microwaves has been observed in experiments where a 250{endash}350 kV, 20{endash}30 A electron beam accelerated in a cyclotron autoresonance accelerator (CARA) passes through a cavity tuned gyroharmonic) and at 8.6 GHz (3rd harmonic) will be described. Theory indicates that high conversion efficiency can be obtained for a high quality beam injected into CARA, and when mode competition can be controlled. Comparisons will be made between the experiments and theory. Planned 7th harmonic experiments will also be described, in which phase matching between the TE-72 mode at 20 GHz, and the TE-11 mode at 2.86 GHz, allows efficient 20 GHz co-generation within the CARA waveguide itself. {copyright} {ital 1999 American Institute of Physics.}

  19. Gyroharmonic conversion experiments

    SciTech Connect (OSTI)

    Hirshfield, J. L.; LaPointe, M. A. [Omega-P, Inc., New Haven, Connecticut 06520 (United States); Yale University, New Haven, Connecticut 06511 (United States); Ganguly, A. K. [Omega-P, Inc., New Haven, Connecticut 06520 (United States)

    1999-05-07

    Generation of high power microwaves has been observed in experiments where a 250-350 kV, 20-30 A electron beam accelerated in a cyclotron autoresonance accelerator (CARA) passes through a cavity tuned gyroharmonic) and at 8.6 GHz (3rd harmonic) will be described. Theory indicates that high conversion efficiency can be obtained for a high quality beam injected into CARA, and when mode competition can be controlled. Comparisons will be made between the experiments and theory. Planned 7th harmonic experiments will also be described, in which phase matching between the TE-72 mode at 20 GHz, and the TE-11 mode at 2.86 GHz, allows efficient 20 GHz co-generation within the CARA waveguide itself.

  20. Solar-Driven Microbial Photoelectrochemical System for Energy Conversion

    E-Print Network [OSTI]

    Wang, Hanyu

    2015-01-01

    photo-anode based solar microbial energy conversion system,C. J. N. , Solar Energy Powered Microbial Fuel Cell with aLight Energy to Bioelectricity: Photosynthetic Microbial

  1. Thermoelectrici Conversion of Waste Heat to Electricity in an...

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

    Vehicle Thermoelectrici Conversion of Waste Heat to Electricity in an IC Engine-Powered Vehicle 2005 Diesel Engine Emissions Reduction (DEER) Conference Presentations and Posters...

  2. Thermoelectric Conversion of Waste Heat to Electricity in an...

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

    unit in an over-the-road truck system. schock.pdf More Documents & Publications Thermoelectric Conversion of Wate Heat to Electricity in an IC Engine Powered Vehicle...

  3. Thermoelectric Conversion of Waste Heat to Electricity in an...

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

    in an Over the Road Diesel Powered Engine System by the Application of Advanced Thermoelectric Systems Implemented in a Hybrid Configuration Thermoelectric Conversion of Waste...

  4. Thermoelectric Conversion of Waste Heat to Electricity in an...

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

    using thermoelectrics on a OTR truck schock.pdf More Documents & Publications Thermoelectric Conversion of Waste Heat to Electricity in an IC Engine Powered Vehicle...

  5. Thermoelectric Conversion of Waste Heat to Electricity in an...

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

    Review and Peer Evaluation ace049schock2011o.pdf More Documents & Publications Thermoelectric Conversion of Waste Heat to Electricity in an IC Engine Powered Vehicle...

  6. System and method for measuring particles in a sample stream of a flow cytometer using a low power laser source

    DOE Patents [OSTI]

    Graves, Steven W; Habbersett, Robert C

    2013-10-22

    A system and method for analyzing a particle in a sample stream of a flow cytometer or the like. The system has a light source, such as a laser pointer module, for generating a low powered light beam and a fluidics apparatus which is configured to transport particles in the sample stream at substantially low velocity through the light beam for interrogation. Detectors, such as photomultiplier tubes, are configured to detect optical signals generated in response to the light beam impinging the particles. Signal conditioning circuitry is connected to each of the detectors to condition each detector output into electronic signals for processing and is designed to have a limited frequency response to filter high frequency noise from the detector output signals.

  7. System and method for measuring particles in a sample stream of a flow cytometer using low-power laser source

    DOE Patents [OSTI]

    Graves, Steven W.; Habbersett, Robert C.

    2014-07-01

    A system and method for analyzing a particle in a sample stream of a flow cytometer or the like. The system has a light source, such as a laser pointer module, for generating a low powered light beam and a fluidics apparatus which is configured to transport particles in the sample stream at substantially low velocity through the light beam for interrogation. Detectors, such as photomultiplier tubes, are configured to detect optical signals generated in response to the light beam impinging the particles. Signal conditioning circuitry is connected to each of the detectors to condition each detector output into electronic signals for processing and is designed to have a limited frequency response to filter high frequency noise from the detector output signals.

  8. Topological Performance Measures as Surrogates for Physical Flow Models for Risk and Vulnerability Analysis for Electric Power Systems

    E-Print Network [OSTI]

    LaRocca, Sarah; Hassel, Henrik; Guikema, Seth

    2013-01-01

    Critical infrastructure systems must be both robust and resilient in order to ensure the functioning of society. To improve the performance of such systems, we often use risk and vulnerability analysis to find and address system weaknesses. A critical component of such analyses is the ability to accurately determine the negative consequences of various types of failures in the system. Numerous mathematical and simulation models exist which can be used to this end. However, there are relatively few studies comparing the implications of using different modeling approaches in the context of comprehensive risk analysis of critical infrastructures. Thus in this paper, we suggest a classification of these models, which span from simple topologically-oriented models to advanced physical flow-based models. Here, we focus on electric power systems and present a study aimed at understanding the tradeoffs between simplicity and fidelity in models used in the context of risk analysis. Specifically, the purpose of this pa...

  9. Parallel computation of Gauss-Seidel type algorithms for power flow analysis 

    E-Print Network [OSTI]

    Ongsakul, Weerakorn

    1991-01-01

    of Iteration Numbers and CPU Time 25 ; III Comparison of CPU Time per Iteration and per Bus Iteration IV Number of Operations per Iteration per Bus 26 32. V Summary of Connections and Connectivity Degree in IEEE 14 Bus System VI Number of Colored Buses... in Standard IEEE System 61, VII Summary of Colored Bus Numbers 62 ' VIII CPU Times to Color Power System in 3 Colors 63 ' IX CPU Times Data to Color Texas 2429 Bus System as the Available Color Numbers Vary . X Color-by-Color Synchronized Implementation...

  10. Microsoft PowerPoint - Proposal-Review-Flow-Chart_2013.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 widelySmallBPA Prepayment Program 202 Jon

  11. Plasmonic conversion of solar energy

    E-Print Network [OSTI]

    Clavero, Cesar

    2014-01-01

    solar energy conversion .This new paradigm of solar energy conversion, based on theon this field, solar energy conversion aimed at photovoltaic

  12. Sandia Energy - Wavelength Conversion Materials

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

    Wavelength Conversion Materials Home Energy Research EFRCs Solid-State Lighting Science EFRC Overview Wavelength Conversion Materials Wavelength Conversion MaterialsAlyssa...

  13. Nonlinear power flow feedback control for improved stability and performance of airfoil sections

    DOE Patents [OSTI]

    Wilson, David G.; Robinett, III, Rush D.

    2013-09-03

    A computer-implemented method of determining the pitch stability of an airfoil system, comprising using a computer to numerically integrate a differential equation of motion that includes terms describing PID controller action. In one model, the differential equation characterizes the time-dependent response of the airfoil's pitch angle, .alpha.. The computer model calculates limit-cycles of the model, which represent the stability boundaries of the airfoil system. Once the stability boundary is known, feedback control can be implemented, by using, for example, a PID controller to control a feedback actuator. The method allows the PID controller gain constants, K.sub.I, K.sub.p, and K.sub.d, to be optimized. This permits operation closer to the stability boundaries, while preventing the physical apparatus from unintentionally crossing the stability boundaries. Operating closer to the stability boundaries permits greater power efficiencies to be extracted from the airfoil system.

  14. Adaptive Finite element approximation of steady flows of incompressible fluids with implicit power-law-like rheology

    E-Print Network [OSTI]

    Christian Kreuzer; Endre Süli

    2015-03-18

    We develop the a posteriori error analysis of finite element approximations of implicit power-law-like models for viscous incompressible fluids. The Cauchy stress and the symmetric part of the velocity gradient in the class of models under consideration are related by a, possibly multi--valued, maximal monotone $r$-graph, with $\\frac{2d}{d+1}finite element residual, as well as the local stability of the error bound. We then consider an adaptive finite element approximation of the problem, and, under suitable assumptions, we show the weak convergence of the adaptive algorithm to a weak solution of the boundary-value problem. The argument is based on a variety of weak compactness techniques, including Chacon's biting lemma and a finite element counterpart of the Acerbi--Fusco Lipschitz truncation of Sobolev functions, introduced by L. Diening, C. Kreuzer and E. S\\"uli [Finite element approximation of steady flows of incompressible fluids with implicit power-law-like rheology. SIAM J. Numer. Anal., 51(2), 984--1015].

  15. Improving PbS Quantum Dot Solar Cell Power Conversion Efficiency to an NREL-Certified 4.4% (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-01-01

    Transition metal oxide improves overall efficiency and maintains performance with inexpensive metals. A research team at the National Renewable Energy Laboratory (NREL) has demonstrated that inserting a transition metal oxide (TMO) between the lead sulfide (PbS) quantum dot (QD) layer and the metal electrode eliminates the Schottky barrier that impedes efficient hole extraction and thereby improves the overall conversion efficiency. This allows for inexpensive metals such as Al to be employed without loss of performance. n-type TMOs consisting of molybdenum oxide (MoO{sub x}) and vanadium oxide (V{sub 2}O{sub x}) were used as an efficient hole extraction layer (HEL) in heterojunction ZnO/PbS QD solar cells. A 4.4% NREL-certified device was reported based on the MoO{sub x} HEL with Al as the back contact material, representing a more than 65% efficiency improvement compared with the case of Au contacting the PbS QD layer directly. The team finds the acting mechanism of the HEL to be a dipole formed at the MoO{sub x} and PbS interface, which enhances band bending to allow efficient hole extraction from the valence band of the PbS layer by MoO{sub x}. The carrier transport to the metal anode is likely enhanced through shallow gap states in the MoO{sub x} layer.

  16. EIS-0036: Coal Conversion Program, New England Power Company, Brayton Point Generating Station Plants 1, 2 and 3, Sommerset, Bristol County, Massachusetts

    Broader source: Energy.gov [DOE]

    The Economic Regulatory Administration developed this EIS to evaluate the site-specific environmental impacts of issuing a Notice of Effectiveness to New England Power Company's Brayton Point Generating Station, Units 1, 2 and 3 to prohibit burning of gas or oil as the primary source of fuel.

  17. Electro-mechanical energy conversion system having a permanent magnet machine with stator, resonant transfer link and energy converter controls

    DOE Patents [OSTI]

    Skeist, S. Merrill; Baker, Richard H.

    2006-01-10

    An electro-mechanical energy conversion system coupled between an energy source and an energy load comprising an energy converter device including a permanent magnet induction machine coupled between the energy source and the energy load to convert the energy from the energy source and to transfer the converted energy to the energy load and an energy transfer multiplexer to control the flow of power or energy through the permanent magnetic induction machine.

  18. Ocean Thermal Energy Conversion LUIS A. VEGA

    E-Print Network [OSTI]

    demand due to emerging economies like China, India, and Brazil. Coal and natural gas resources 7296 OOcean Thermal Energy Conversion LUIS A. VEGA Hawaii Natural Energy Institute, School of Ocean the OTEC plant. The difference between gross power and in-plant power consumption needed to run all sweater

  19. Thermoelectric Conversion of Wate Heat to Electricity in an IC...

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

    Wate Heat to Electricity in an IC Engine Powered Vehicle Thermoelectric Conversion of Wate Heat to Electricity in an IC Engine Powered Vehicle Presentation given at the 16th...

  20. Energy Conversion and Storage Program

    SciTech Connect (OSTI)

    Cairns, E.J.

    1992-03-01

    The Energy Conversion and Storage Program applies chemistry and materials science principles to solve problems in (1) production of new synthetic fuels, (2) development of high-performance rechargeable batteries and fuel cells, (3) development of advanced thermochemical processes for energy conversion, (4) characterization of complex chemical processes, and (5) application of novel materials for energy conversion and transmission. Projects focus on transport-process principles, chemical kinetics, thermodynamics, separation processes, organic and physical chemistry, novel materials, and advanced methods of analysis. Electrochemistry research aims to develop advanced power systems for electric vehicle and stationary energy storage applications. Topics include identification of new electrochemical couples for advanced rechargeable batteries, improvements in battery and fuel-cell materials, and the establishment of engineering principles applicable to electrochemical energy storage and conversion. Chemical Applications research includes topics such as separations, catalysis, fuels, and chemical analyses. Included in this program area are projects to develop improved, energy-efficient methods for processing waste streams from synfuel plants and coal gasifiers. Other research projects seek to identify and characterize the constituents of liquid fuel-system streams and to devise energy-efficient means for their separation. Materials Applications research includes the evaluation of the properties of advanced materials, as well as the development of novel preparation techniques. For example, the use of advanced techniques, such as sputtering and laser ablation, are being used to produce high-temperature superconducting films.

  1. Isolated and soft-switched power converter

    DOE Patents [OSTI]

    Peng, Fang Zheng (Knoxville, TN); Adams, Donald Joe (Knoxville, TN)

    2002-01-01

    An isolated and soft-switched power converter is used for DC/DC and DC/DC/AC power conversion. The power converter includes two resonant tank circuits coupled back-to-back through an isolation transformer. Each resonant tank circuit includes a pair of resonant capacitors connected in series as a resonant leg, a pair of tank capacitors connected in series as a tank leg, and a pair of switching devices with anti-parallel clamping diodes coupled in series as resonant switches and clamping devices for the resonant leg. The power converter is well suited for DC/DC and DC/DC/AC power conversion applications in which high-voltage isolation, DC to DC voltage boost, bidirectional power flow, and a minimal number of conventional switching components are important design objectives. For example, the power converter is especially well suited to electric vehicle applications and load-side electric generation and storage systems, and other applications in which these objectives are important. The power converter may be used for many different applications, including electric vehicles, hybrid combustion/electric vehicles, fuel-cell powered vehicles with low-voltage starting, remote power sources utilizing low-voltage DC power sources, such as photovoltaics and others, electric power backup systems, and load-side electric storage and generation systems.

  2. To cite this version : Rigo-Mariani, Rmy and Sareni, Bruno and Roboam, Xavier Fast Power Flow Scheduling and Sensitivity Analysis for Sizing a

    E-Print Network [OSTI]

    Mailhes, Corinne

    dispatching of power flows in a microgrid with storage. The investigated approach is based on the use Scheduling and Sensitivity Analysis for Sizing a Microgrid with Storage. (2014) In: 11th International FOR SIZING A MICROGRID WITH STORAGE R. Rigo-Mariani1 , B. Sareni1 , X. Roboam1 1. Université de Toulouse

  3. To cite this version : Rigo-Mariani, Rmy and Sareni, Bruno and Roboam, Xavier Fast Power Flow Scheduling and Sensitivity Analysis for Sizing a

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    for optimal dispatching of power flows in a microgrid with storage. The investigated approach is based Scheduling and Sensitivity Analysis for Sizing a Microgrid with Storage. (2014) In: 11th International ANALYSIS FOR SIZING A MICROGRID WITH STORAGE R. Rigo-Mariani1 , B. Sareni1 , X. Roboam1 1. Université de

  4. may also explain the larger extent of quiet Sun spicules1,2 mode power and granular flows are stronger by up to 50% and

    E-Print Network [OSTI]

    Johnson, Peter D.

    may also explain the larger extent of quiet Sun spicules1,2 where p- mode power and granular flows 2004; doi:10.1038/nature02749. 1. Beckers, J. M. Solar spicules. Sol. Phys. 3, 367­433 (1968). 2. Beckers, J. M. Solar spicules. Annu. Rev. Astron. Astrophys. 10, 73­100 (1972). 3. Sterling, A. C. Solar

  5. 1982 annual report: Biomass Thermochemical Conversion Program

    SciTech Connect (OSTI)

    Schiefelbein, G.F.; Stevens, D.J.; Gerber, M.A.

    1983-01-01

    This report provides a brief overview of the Thermochemical Conversion Program's activities and major accomplishments during fiscal year 1982. The objective of the Biomass Thermochemical Conversion Program is to generate scientific data and fundamental biomass converison process information that, in the long term, could lead to establishment of cost effective processes for conversion of biomass resources into clean fuels and petrochemical substitutes. The goal of the program is to improve the data base for biomass conversion by investigating the fundamental aspects of conversion technologies and exploring those parameters which are critical to these conversion processes. To achieve this objective and goal, the Thermochemical Conversion Program is sponsoring high-risk, long-term research with high payoff potential which industry is not currently sponsoring, nor is likely to support. Thermochemical conversion processes employ elevated temperatures to convert biomass materials into energy. Process examples include: combustion to produce heat, steam, electricity, direct mechanical power; gasification to produce fuel gas or synthesis gases for the production of methanol and hydrocarbon fuels; direct liquefaction to produce heavy oils or distillates; and pyrolysis to produce a mixture of oils, fuel gases, and char. A bibliography of publications for 1982 is included.

  6. Sandia Energy - Power Towers for Utilities

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

    Power Towers for Utilities Home Stationary Power Energy Conversion Efficiency Solar Energy Concentrating Solar Power (CSP) National Solar Thermal Test Facility Central Receiver...

  7. Electrokinetic Power Generation from Liquid Water Microjets

    E-Print Network [OSTI]

    Duffin, Andrew M.

    2008-01-01

    Electrokinetic Power Generation from Liquid Water MicrojetsElectrokinetic power generation using liquid water microjetscalculations of power generation and conversion efficiency.

  8. Transparency in nonlinear frequency conversion

    E-Print Network [OSTI]

    Longhi, Stefano

    2015-01-01

    Suppression of wave scattering and the realization of transparency effects in engineered optical media and surfaces have attracted great attention in the past recent years. In this work the problem of transparency is considered for optical wave propagation in a nonlinear dielectric medium with second-order $\\chi^{(2)}$ susceptibility. Because of nonlinear interaction, a reference signal wave at carrier frequency $\\omega_1$ can exchange power, thus being amplified or attenuated,when phase matching conditions are satisfied and frequency conversion takes place. Therefore, rather generally the medium is not transparent to the signal wave because of 'scattering' in the frequency domain. Here we show that broadband transparency, corresponding to the full absence of frequency conversion in spite of phase matching, can be observed for the signal wave in the process of sum frequency generation whenever the effective susceptibility $\\chi^{(2)}$ along the nonlinear medium is tailored following a suitable spatial apodiza...

  9. Optimization and Analysis of High-Power Hydrogen/Bromine-Flow Batteries for Grid-Scale Energy Storage

    SciTech Connect (OSTI)

    Cho, KT; Albertus, P; Battaglia, V; Kojic, A; Srinivasan, V; Weber, AZ

    2013-10-07

    For storage of grid-scale electrical energy, redox-flow batteries (RFBs) are considered promising technologies. This paper explores the influence of electrolyte composition and ion transport on cell performance by using an integrated approach of experiments and cost modeling. In particular, the impact of the area-specific resistance on system capability is elucidated for the hydrogen/bromine RFB. The experimental data demonstrate very good performance with 1.46 W cm(-2) peak power and 4 A cm(-2) limiting current density at ambient conditions for an optimal cell design and reactant concentrations. The data and cost model results show that higher concentrations of RFB reactants do not necessarily result in lower capital cost as there is a tradeoff between cell performance and storage (tank) requirements. In addition, the discharge time and overall efficiency demonstrate nonlinear effects on system cost, with a 3 to 4 hour minimum discharge time showing a key transition to a plateau in terms of cost for typical RFB systems. The presented results are applicable to many different RFB chemistries and technologies and highlight the importance of ohmic effects and associated area-specific resistance on RFB viability.

  10. In-space power rejection management via indirect annular flow liquid film management - process design and feasibility 

    E-Print Network [OSTI]

    Williams, Rube Ben

    1993-01-01

    flow and the required condensation rate. Large film thicknesses (small void fractions) are limited by the requirement that the condensing channels must discharge two-phase annular flow (discussed in this chapter, see FLOW REGIME RESTRICTION... Channel for Four Cases of the Ambient Radiation Load. The Void Fraction for Two-Phase Annular Flow was Predicted by the Wheeler Void Fraction Correlation . Figure 35. Comparison of the Void Fraction in a SLIC Condensing Channel for Four Cases...

  11. Determination of maximum reactor power level consistent with the requirement that flow reversal occurs without fuel damage

    SciTech Connect (OSTI)

    Rao, D.V.; Darby, J.L.; Ross, S.B.; Clark, R.A. [Science and Engineering Associates, Inc., Albuquerque, NM (United States)

    1990-04-19

    The High Flux Beam Reactor (HFBR) operated by Brookhaven National Laboratory (BNL) employs forced downflow for heat removal during normal operation. In the event of total loss of forced flow, the reactor will shutdown and the flow reversal valves open. When the downward core flow becomes sufficiently small then the opposing thermal buoyancy induces flow reversal leading to decay heat removal by natural convection. There is some uncertainty as to whether the natural circulation is adequate for decay heat removal after 60 MW operation. BNL- staff carried out a series of calculations to establish the adequacy of flow reversal to remove decay heat. Their calculations are based on a natural convective CHF model. The primary purpose of the present calculations is to review the accuracy and applicability of Fauske`s CHF model for the HFBR, and the assumptions and methodology employed by BNL-staff to determine the heat removal limit in the HFBR during a flow reversal and natural convection situation.

  12. Transport-driven scrape-off layer flows and the x-point dependence of the L-H power threshold in Alcator C-Mod

    SciTech Connect (OSTI)

    LaBombard, B.; Rice, J.E.; Hubbard, A.E.; Hughes, J.W.; Greenwald, M.; Granetz, R.S.; Irby, J.H.; Lin, Y.; Lipschultz, B.; Marmar, E.S.; Marr, K.; Mossessian, D.; Parker, R.; Rowan, W.; Smick, N.; Snipes, J.A.; Terry, J.L.; Wolfe, S.M.; Wukitch, S.J.

    2005-05-15

    Factor of {approx}2 higher power thresholds for low- to high-confinement mode transitions (L-H) with unfavorable x-point topologies in Alcator C-Mod [Phys. Plasmas 1, 1511 (1994)] are linked to flow boundary conditions imposed by the scrape-off layer (SOL). Ballooning-like transport drives flow along magnetic field lines from low- to high-field regions with toroidal direction dependent on upper/lower x-point balance; the toroidal rotation of the confined plasma responds, exhibiting a strong counter-current rotation when Bx{nabla}B points away from the x point. Increased auxiliary heating power (rf, no momentum input) leads to an L-H transition at approximately twice the edge electron pressure gradient when Bx{nabla}B points away. As gradients rise prior to the transition, toroidal rotation ramps toward the co-current direction; the H mode is seen when the counter-current rotation imposed by the SOL flow becomes compensated. Remarkably, L-H thresholds in lower-limited discharges are identical to lower x-point discharges; SOL flows are also found similar, suggesting a connection.

  13. Episodic jet power extracted from a spinning black hole surrounded by a neutrino-dominated accretion flow in gamma-ray bursts

    SciTech Connect (OSTI)

    Cao, Xinwu [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030 (China); Liang, En-Wei [Department of Physics and GXU-NAOC Center for Astrophysics and Space Sciences, Guangxi University, Nanning 530004 (China); Yuan, Ye-Fei, E-mail: cxw@shao.ac.cn, E-mail: lew@gxu.edu.cn, E-mail: yfyuan@ustc.edu.cn [Department of Astronomy, University of Sciences and Technology of China, Hefei, Anhui 230026 (China)

    2014-07-10

    It was suggested that the relativistic jets in gamma-ray bursts (GRBs) are powered via the Blandford-Znajek (BZ) mechanism or the annihilation of neutrinos and anti-neutrinos from a neutrino cooling-dominated accretion flow (NDAF). The advection and diffusion of the large-scale magnetic field of an NDAF is calculated, and the external magnetic field is found to be dragged inward efficiently by the accretion flow for a typical magnetic Prandtl number P{sub m}=?/??1. The maximal BZ jet power can be ?10{sup 53}-10{sup 54} erg s{sup –1} for an extreme Kerr black hole, if an external magnetic field with 10{sup 14} Gauss is advected by the NDAF. This is roughly consistent with the field strength of the disk formed after a tidal disrupted magnetar. The accretion flow near the black hole horizon is arrested by the magnetic field if the accretion rate is below than a critical value for a given external field. The arrested accretion flow fails to drag the field inward and the field strength decays, and then the accretion re-starts, which leads to oscillating accretion. The typical timescale of such episodic accretion is of an order of one second. This can qualitatively explain the observed oscillation in the soft extended emission of short-type GRBs.

  14. Unit 9: Spatial Data Conversion

    E-Print Network [OSTI]

    9, CCTP; Dodson, Rustin

    1998-01-01

    UNIT 9: SPATIAL DATA CONVERSION Written by Rustin Dodson,Programs Page 1 Unit 9: Spatial Data Conversion freezingPrograms Page 2 Unit 9: Spatial Data Conversion Export USGS

  15. Journal of Power Sources 156 (2006) 369374 Predicting the transient response of a serpentine flow-field PEMFC

    E-Print Network [OSTI]

    Van Zee, John W.

    2006-01-01

    -field PEMFC II: Normal to minimal fuel and AIR S. Shimpaleea, W.-K. Leea, J.W. Van Zeea,, H. Naseri in a PEMFC during operation with fixed normal stoichiometic flow rates of hydrogen and air for a 1.0 V s-1 of PEMFCs with fixed gas flow rates may expose the MEA to various degrees of stoichiometry for either

  16. DANISHBIOETHANOLCONCEPT Biomass conversion for

    E-Print Network [OSTI]

    DANISHBIOETHANOLCONCEPT Biomass conversion for transportation fuel Concept developed at RISŘ and DTU Anne Belinda Thomsen (RISŘ) Birgitte K. Ahring (DTU) #12;DANISHBIOETHANOLCONCEPT Biomass: Biogas #12;DANISHBIOETHANOLCONCEPT Pre-treatment Step Biomass is macerated The biomass is cut in small

  17. Mathematical Model Analysis for Hg Flow

    E-Print Network [OSTI]

    McDonald, Kirk

    Mathematical Model Analysis for Hg Flow Yan Zhan SUNYSB April 20th, 2010 #12;Outline · Introduction ­ Mechanism of Jet Breakup & Atomization ­ Dynamic Problems in Hg Target Flow · Mathematical Model for Hg Flow ­ Parameters ­ Incompressible Flow (No MHD) ­ Incompressible Flow (MHD) ­ Proton Beam Energy Conversion

  18. Electrical power conversion is essential for improving

    E-Print Network [OSTI]

    Langendoen, Koen

    energy. Diploma Master of Science Electrical Engineering Track: Electrical Sustainable Energy Credits 120 markets. Electrical sustainable energy engineers are needed in order to design new components with an eye Engineering at TU Delft offers the track: Electrical Sustainable Energy. If you are interested in getting

  19. Battery Chargers | Electrical Power Conversion and Storage

    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 uBUS SERVICE SUBSIDIESDepartment of585 OctoberEV-- v1.0 More|

  20. Artificial Neural Network for Optimized Power System Management

    E-Print Network [OSTI]

    OLeary, Daniel Albert

    2015-01-01

    production data • Day - when solar energy is consistent (onvolatility of the solar energy production data Solar Power [conversion of solar radiation data. Energy Conversion and

  1. Thermoelectric Conversion of Waste Heat to Electricity in an...

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

    T estimated to be 500 oC deer09schock.pdf More Documents & Publications Thermoelectric Conversion of Waste Heat to Electricity in an IC Engine Powered Vehicle...

  2. The heat recovery steam generator (HRSG) is a key component of Combined Cycle Power Plants (CCPP). The exhaust (flue gas) from the CCPP gas turbine flows through the HRSG -this gas typically contains a high

    E-Print Network [OSTI]

    The heat recovery steam generator (HRSG) is a key component of Combined Cycle Power Plants (CCPP). The exhaust (flue gas) from the CCPP gas turbine flows through the HRSG - this gas typically contains a high

  3. Direct conversion technology

    SciTech Connect (OSTI)

    Massier, P.F.; Back, L.H.; Ryan, M.A.; Fabris, G.

    1992-01-07

    The overall objective of the Direct Conversion Technology task is to develop an experimentally verified technology base for promising direct conversion systems that have potential application for energy conservation in the end-use sectors. This report contains progress of research on the Alkali Metal Thermal-to-Electric Converter (AMTEC) and on the Two-Phase Liquid-Metal MHD Electrical Generator (LMMHD) for the period January 1, 1991 through December 31, 1991. Research on AMTEC and on LMMHD was initiated during October 1987. Reports prepared on previous occasions (Refs. 1--5) contain descriptive and performance discussions of the following direct conversion concepts: thermoelectric, pyroelectric, thermionic, thermophotovoltaic, thermoacoustic, thermomagnetic, thermoelastic (Nitionol heat engine); and also, more complete descriptive discussions of AMTEC and LMMHD systems.

  4. Digital optical conversion module

    DOE Patents [OSTI]

    Kotter, D.K.; Rankin, R.A.

    1988-07-19

    A digital optical conversion module used to convert an analog signal to a computer compatible digital signal including a voltage-to-frequency converter, frequency offset response circuitry, and an electrical-to-optical converter. Also used in conjunction with the digital optical conversion module is an optical link and an interface at the computer for converting the optical signal back to an electrical signal. Suitable for use in hostile environments having high levels of electromagnetic interference, the conversion module retains high resolution of the analog signal while eliminating the potential for errors due to noise and interference. The module can be used to link analog output scientific equipment such as an electrometer used with a mass spectrometer to a computer. 2 figs.

  5. Direct Conversion Technology

    SciTech Connect (OSTI)

    Back, L.H.; Fabris, G.; Ryan, M.A.

    1992-07-01

    The overall objective of the Direct Conversion Technology task is to develop an experimentally verified technology base for promising direct conversion systems that have potential application for energy conservation in the end-use sectors. Initially, two systems were selected for exploratory research and advanced development. These are Alkali Metal Thermal-to-Electric Converter (AMTEC) and Two-Phase Liquid Metal MD Generator (LMMHD). This report describes progress that has been made during the first six months of 1992 on research activities associated with these two systems. (GHH)

  6. A Simple Optimal Power Flow Model with Energy Storage K. Mani Chandy, Steven H. Low, Ufuk Topcu and Huan Xu

    E-Print Network [OSTI]

    Xu, Huan

    is motivated by the intensifying trend to deploy renewable energy such as wind or solar power. In the state and Huan Xu Abstract-- The integration of renewable energy generation, such as wind power in the Tehachapi area in California [10]. Not only is renewable energy more environmentally friendly, but its

  7. An Energy-Flow Model for Self-Powered Routers and its Application for Energy-Aware Routing

    E-Print Network [OSTI]

    Belding-Royer, Elizabeth M.

    of electrical energy. Depen- dence on renewable energy sources and variable power consump- tion make harvesting equipment hardware specifi- cations; high resolution, time-varying weather information settings, rural wireless deploy- ments often have to face the lack of reliable grid power infrastruc- ture

  8. Photovoltaic Energy Conversion

    E-Print Network [OSTI]

    Glashausser, Charles

    Photovoltaic Energy Conversion Frank Zimmermann #12;Solar Electricity Generation Consumes no fuel Electrode Valence Band Conduction Band Fermi Level I- /I3 - Redox Potential Dye 1D 3D* 1D* Energy Levels Counter Electrode Valence Band Conduction Band Fermi Level I- /I3 - Redox Potential Dye 1D 3D* 1D* Energy

  9. ENERGY CONVERSION Spring 2011

    E-Print Network [OSTI]

    Bahrami, Majid

    , 5th Edition Michael J. Moran and Howard N. Shapiro, John Wiley and Sons Inc., New York, NY, 2004, John Willey 2010. 3) Alternative Energy Systems and Applications, by B.K. Hodge, John Willey 2010. 41 ENSC 461 ENERGY CONVERSION Spring 2011 Instructor: Dr. Majid Bahrami 4372 Email

  10. Redox Flow Batteries, a Review

    E-Print Network [OSTI]

    Weber, Adam Z.

    2013-01-01

    of a Vanadium Redox-Flow Battery to Maintain Power Quality,"Fuel System Using Redox Flow Battery," ed: WO Patentand D. B. Hickey, "Redox Flow Battery System for Distributed

  11. The State of the Art of Generators for Wind Energy Conversion Systems

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    243 1 The State of the Art of Generators for Wind Energy Conversion Systems Y. Amirat, M. E. H. Benbouzid, B. Bensaker, R. Wamkeue and H. Mangel Abstract--Wind Energy Conversion Systems (WECS) have become of the studied generators is provided in Fig. 2. II. WIND ENERGY BACKGROUND A. Wind Power Conversion

  12. Study of Power Converter Topologies with Energy Recovery and grid power flow control. Part A: 2-quadrant converter with energy storage.

    E-Print Network [OSTI]

    Maestri, S; Uicich, G; Benedetti, M; Le Godec, G; Papastergiou, K

    2015-01-01

    In the framework of a Transfer line (TT2) Consolidation Programme, a number of studies on Energy cycling have been commissioned. Part of this work involves the study of different power electronic system topologies for magnet energy recovery [1{5]. In this report, the use of a two-quadrant (2Q) regulator connected to the DC link of a 4-quadrant magnet supply is analysed. The key objective of the study is to find control strategies that result in the control of the peak power required from the power network as well as to recover the magnet energy into capacitor banks with controlled voltage fluctuation. The study comprises the modelling of the system by means of the method of state averaging and the development of regulation strategies to energy management. The proposed control strategies can be divided in two groups: in the first group, the magnet current is used to dene the reference for the control system, while in the second group this current is considered as a perturbation and some strategies are devised ...

  13. Proceedings of the 25th intersociety energy conversion engineering conference

    SciTech Connect (OSTI)

    Nelson, P.A.; Schertz, W.W.; Till, R.H.

    1990-01-01

    This book contains the proceedings of the 25th Intersociety Energy Conversion Engineering Conference. Volume 5 is organized under the following headings: Photovoltaics I, Photovoltaics II, Geothermal power, Thermochemical conversion of biomass, Energy from waste and biomass, Solar thermal systems for environmental applications, Solar thermal low temperature systems and components, Solar thermal high temperature systems and components, Wind systems, Space power sterling technology Stirling cooler developments, Stirling solar terrestrial I, Stirling solar terrestrial II, Stirling engine generator sets, Stirling models and simulations, Stirling engine analysis, Stirling models and simulations, Stirling engine analysis, Stirling engine loss understanding, Novel engine concepts, Coal conversion and utilization, Power cycles, MHD water propulsion I, Underwater vehicle powerplants - performance, MHD underwater propulsion II, Nuclear power, Update of advanced nuclear power reactor concepts.

  14. EIS-0083: Final Northeast Regional Environmental Impact Statement; The Potential Conversion of Forty-Two Powerplants From Oil to Coal or Alternate Fuels

    Broader source: Energy.gov [DOE]

    This Economic Regulatory Administration statement assesses the potential for cumulative and interactive environmental impacts resulting from conversion of up to 42 northeastern power plants from oil to coal and from an alternative “Voluntary Conversion” scenario for 27 power plants.

  15. Multi Megawatt Power System Analysis Report

    SciTech Connect (OSTI)

    Longhurst, Glen Reed; Harvego, Edwin Allan; Schnitzler, Bruce Gordon; Seifert, Gary Dean; Sharpe, John Phillip; Verrill, Donald Alan; Watts, Kenneth Donald; Parks, Benjamin Travis

    2001-11-01

    Missions to the outer planets or to near-by planets requiring short times and/or increased payload carrying capability will benefit from nuclear power. A concept study was undertaken to evaluate options for a multi-megawatt power source for nuclear electric propulsion. The nominal electric power requirement was set at 15 MWe with an assumed mission profile of 120 days at full power, 60 days in hot standby, and another 120 days of full power, repeated several times for 7 years of service. Of the numerous options considered, two that appeared to have the greatest promise were a gas-cooled reactor based on the NERVA Derivative design, operating a closed cycle Brayton power conversion system; and a molten lithium-cooled reactor based on SP-100 technology, driving a boiling potassium Rankine power conversion system. This study examined the relative merits of these two systems, seeking to optimize the specific mass. Conclusions were that either concept appeared capable of approaching the specific mass goal of 3-5 kg/kWe estimated to be needed for this class of mission, though neither could be realized without substantial development in reactor fuels technology, thermal radiator mass efficiency, and power conversion and distribution electronics and systems capable of operating at high temperatures. Though the gas-Brayton systems showed an apparent advantage in specific mass, differences in the degree of conservatism inherent in the models used suggests expectations for the two approaches may be similar. Brayton systems eliminate the need to deal with two-phase flows in the microgravity environment of space.

  16. Advanced Stirling conversion systems for terrestrial applications

    SciTech Connect (OSTI)

    Shaltens, R.K.

    1987-01-01

    Sandia National Laboratories (SNLA) is developing heat engines for terrestrial Solar distributed Heat Receivers. SNLA has identified the Stirling to be one of the most promising candidates for the terrestrial applications. The free-piston Stirling engine (FPSE) has the potential to meet the DOE goals for both performance and cost. Free-piston Stirling activities which are directed toward a dynamic power source for the space application are being conducted. Space power system requirements include high efficiency, very long life, high reliability and low vibration. The FPSE has the potential for future high power space conversion systems, either solar or nuclear powered. Generic free-piston technology is currently being developed for use with a residential heat pump under an Interagency Agreement. Also, an overview is presented of proposed conceptual designs for the Advanced Stirling Conversion System (ASCS) using a free-piston Stirling engine and a liquid metal heat pipe receiver. Power extraction includes both a linear alternator and hydraulic output capable of delivering approximately 25 kW of electrical power to the electric utility grid. Target cost of the engine/alternator is 300 dollars per kilowatt at a manufacturing rate of 10,000 units per year. The design life of the ASCS is 60,000 h (30 y) with an engine overhaul at 40,000 h (20 y). Also discussed are the key features and characteristics of the ASCS conceptual designs.

  17. Ocean Thermal Energy Conversion Basics

    Broader source: Energy.gov [DOE]

    A process called ocean thermal energy conversion (OTEC) uses the heat energy stored in the Earth's oceans to generate electricity.

  18. A Simple Optimal Power Flow Model with Energy Storage K. Mani Chandy, Steven H. Low, Ufuk Topcu and Huan Xu

    E-Print Network [OSTI]

    Chandy, K. Mani

    time periods. The model is motivated by the intensifying trend to deploy renewable energy such as wind and Huan Xu Abstract-- The integration of renewable energy, such as wind power, into the electric grid from wind projects in the Tehachapi area in California [9]. Not only is renewable energy more

  19. Biological Conversion of Sugars To Hydrocarbons | Department...

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

    Biological Conversion of Sugars To Hydrocarbons Biological Conversion of Sugars To Hydrocarbons PDF explaining the biological process of bioenergy Biological Conversion of Sugars...

  20. Flexible Conversion Ratio Fast Reactor Systems Evaluation

    SciTech Connect (OSTI)

    Neil Todreas; Pavel Hejzlar

    2008-06-30

    Conceptual designs of lead-cooled and liquid salt-cooled fast flexible conversion ratio reactors were developed. Both concepts have cores reated at 2400 MWt placed in a large-pool-type vessel with dual-free level, which also contains four intermediate heat exchanges coupling a primary coolant to a compact and efficient supercritical CO2 Brayton cycle power conversion system. Decay heat is removed passively using an enhanced Reactor Vessel Auxiliary Cooling System and a Passive Secondary Auxiliary Cooling System. The most important findings were that (1) it is feasible to design the lead-cooled and salt-cooled reactor with the flexible conversion ratio (CR) in the range of CR=0 and CR=1 n a manner that achieves inherent reactor shutdown in unprotected accidents, (2) the salt-cooled reactor requires Lithium thermal Expansion Modules to overcme the inherent salt coolant's large positive coolant temperature reactivity coefficient, (3) the preferable salt for fast spectrum high power density cores is NaCl-Kcl-MgCl2 as opposed to fluoride salts due to its better themal-hydraulic and neutronic characteristics, and (4) both reactor, but attain power density 3 times smaller than that of the sodium-cooled reactor.

  1. Next-Generation Thermionic Solar Energy Conversion

    Broader source: Energy.gov [DOE]

    This fact sheet describes a next-generation thermionic solar energy conversion project awarded under the DOE's 2012 SunShot Concentrating Solar Power R&D award program. The team, led by Stanford University, seeks to demonstrate the feasibility of photon-enhanced, microfabricated thermionic energy converters as a high-efficiency topping cycle for CSP electricity generation. With the potential to double the electricity output efficiency of solar-thermal power stations, this topping cycle application can significantly reduce the cost of solar-thermal electricity below that of the lowest-cost, fossil-fuel generated electricity.

  2. Flow Characteristics Analysis of Widows' Creek Type Control Valve for Steam Turbine Control

    SciTech Connect (OSTI)

    Yoo, Yong H.; Sohn, Myoung S.; Suh, Kune Y.

    2006-07-01

    The steam turbine converts the kinetic energy of steam to mechanical energy of rotor blades in the power conversion system of fossil and nuclear power plants. The electric output from the generator of which the rotor is coupled with that of the steam turbine depends on the rotation velocity of the steam turbine bucket. The rotation velocity is proportional to the mass flow rate of steam entering the steam turbine through valves and nozzles. Thus, it is very important to control the steam mass flow rate for the load following operation of power plants. Among various valves that control the steam turbine, the control valve is most significant. The steam flow rate is determined by the area formed by the stem disk and the seat of the control valve. While the ideal control valve linearly controls the steam mass flow rate with its stem lift, the real control valve has various flow characteristic curves pursuant to the stem lift type. Thus, flow characteristic curves are needed to precisely design the control valves manufactured for the operating conditions of nuclear power plants. OMEGA (Optimized Multidimensional Experiment Geometric Apparatus) was built to experimentally study the flow characteristics of steam flowing inside the control valve. The Widows' Creek type control valve was selected for reference. Air was selected as the working fluid in the OMEGA loop to exclude the condensation effect in this simplified approach. Flow characteristic curves were plotted by calculating the ratio of the measured mass flow rate versus the theoretical mass flow rate of the air. The flow characteristic curves are expected to be utilized to accurately design and operate the control valve for fossil as well as nuclear plants. (authors)

  3. Combustion and direct energy conversion in a micro-combustor 

    E-Print Network [OSTI]

    Lei, Yafeng

    2006-10-30

    . Since batteries have low specific energy (~200 kJ/kg) and liquid hydrocarbon fuels have a very high specific energy (~50000 kJ/kg), a miniaturized power-generating device, even with a relatively inefficient conversion of hydrocarbon fuels to power, would...

  4. Zinc phosphate conversion coatings

    DOE Patents [OSTI]

    Sugama, Toshifumi (Wading River, NY)

    1997-01-01

    Zinc phosphate conversion coatings for producing metals which exhibit enhanced corrosion prevention characteristics are prepared by the addition of a transition-metal-compound promoter comprising a manganese, iron, cobalt, nickel, or copper compound and an electrolyte such as polyacrylic acid, polymethacrylic acid, polyitaconic acid and poly-L-glutamic acid to a phosphating solution. These coatings are further improved by the incorporation of Fe ions. Thermal treatment of zinc phosphate coatings to generate .alpha.-phase anhydrous zinc phosphate improves the corrosion prevention qualities of the resulting coated metal.

  5. Zinc phosphate conversion coatings

    DOE Patents [OSTI]

    Sugama, T.

    1997-02-18

    Zinc phosphate conversion coatings for producing metals which exhibit enhanced corrosion prevention characteristics are prepared by the addition of a transition-metal-compound promoter comprising a manganese, iron, cobalt, nickel, or copper compound and an electrolyte such as polyacrylic acid, polymethacrylic acid, polyitaconic acid and poly-L-glutamic acid to a phosphating solution. These coatings are further improved by the incorporation of Fe ions. Thermal treatment of zinc phosphate coatings to generate {alpha}-phase anhydrous zinc phosphate improves the corrosion prevention qualities of the resulting coated metal. 33 figs.

  6. Conversion Technologies for Advanced Biofuels - Carbohydrates...

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

    webinarcarbohydratesproduction.pdf More Documents & Publications Advanced Conversion Roadmap Workshop Workshop on Conversion Technologies for Advanced Biofuels - Carbohydrates...

  7. Conversion Technologies for Advanced Biofuels - Carbohydrates...

    Energy Savers [EERE]

    More Documents & Publications Conversion Technologies for Advanced Biofuels - Carbohydrates Production Advanced Conversion Roadmap Workshop Innovative Topics for Advanced Biofuels...

  8. Challenges and Opportunities in Thermoelectric Energy Conversion...

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

    Energy Conversion Challenges and Opportunities in Thermoelectric Energy Conversion 2004 Diesel Engine Emissions Reduction (DEER) Conference Presentation: Lawrence Berkeley...

  9. Compact anhydrous HCl to aqueous HCl conversion system

    SciTech Connect (OSTI)

    Grossman, Mark W. (Belmont, MA); Speer, Richard (S. Hamilton, MA)

    1993-01-01

    The present invention is directed to an inexpensive and compact apparatus adapted for use with a .sup.196 Hg isotope separation process and the conversion of anhydrous HCl to aqueous HCl without the use of air flow to carry the HCl vapor into the converter system.

  10. Compact anhydrous HCl to aqueous HCl conversion system

    DOE Patents [OSTI]

    Grossman, M.W.; Speer, R.

    1993-06-01

    The present invention is directed to an inexpensive and compact apparatus adapted for use with a [sup 196]Hg isotope separation process and the conversion of anhydrous HCl to aqueous HCl without the use of air flow to carry the HCl vapor into the converter system.

  11. PowerPoint Presentation

    Energy Savers [EERE]

    to revolutionize the energy efficiency of electric power control and conversion 27 50% Lower Cost Using 75% Less Energy And reuse or recycle >95% of the material Objective Develop...

  12. Chemistry of Furan Conversion into Aromatics and Olefins over HZSM-5: A Model Biomass Conversion Reaction

    SciTech Connect (OSTI)

    Cheng, Yu-Ting; Huber, George W.

    2011-06-03

    The conversion of furan (a model of cellulosic biomass) over HZSM-5 was investigated in a thermogravimetric analysis–mass spectrometry system, in situ Fourier transform infrared analysis, and in a continuous-flow fixed-bed reactor. Furan adsorbed as oligomers at room temperature with a 1.73 of adsorbed furan/Al ratio. These oligomers were polycyclic aromatic compounds that were converted to CO, CO?, aromatics, and olefins at temperatures from 400 to 600 °C. Aromatics (e.g., benzene, toluene, and naphthalene), oligomer isomers (e.g., benzofuran, 2,2-methylenebisfuran, and benzodioxane), and heavy oxygenates (C??{sub +} oligomers) were identified as intermediates formed inside HZSM-5 at different reaction temperatures. During furan conversion, graphite-type coke formed on the catalyst surface, which caused the aromatics and olefins formation to deactivate within the first 30 min of time on-stream. We have measured the effects of space velocity and temperature for furan conversion to help us understand the chemistry of biomass conversion inside zeolite catalysts. The major products for furan conversion included CO, CO?, allene, C?–C? olefins, benzene, toluene, styrene, benzofuran, indene, and naphthalene. The aromatics (benzene and toluene) and olefins (ethylene and propylene) selectivity decreased with increasing space velocity. Unsaturated hydrocarbons such as allene, cyclopentadiene, and aromatics selectivity increased with increasing space velocity. The product distribution was selective to olefins and CO at high temperatures (650 °C) but was selective to aromatics (benzene and toluene) at intermediate temperatures (450–600 °C). At low temperatures (450 °C), benzofuran and coke contributed 60% of the carbon selectivity. Several different reactions were occurring for furan conversion over zeolites. Some important reactions that we have identified in this study include Diels–Alder condensation (e.g., two furans form benzofuran and water), decarbonylation (e.g., furan forms CO and allene), oligomerization (allene forms olefins and aromatics plus hydrogen), and alkylation (e.g., furan plus olefins). The product distribution was far from thermodynamic equilibrium.

  13. Accident Analysis for the NIST Research Reactor Before and After Fuel Conversion

    SciTech Connect (OSTI)

    Baek J.; Diamond D.; Cuadra, A.; Hanson, A.L.; Cheng, L-Y.; Brown, N.R.

    2012-09-30

    Postulated accidents have been analyzed for the 20 MW D2O-moderated research reactor (NBSR) at the National Institute of Standards and Technology (NIST). The analysis has been carried out for the present core, which contains high enriched uranium (HEU) fuel and for a proposed equilibrium core with low enriched uranium (LEU) fuel. The analyses employ state-of-the-art calculational methods. Three-dimensional Monte Carlo neutron transport calculations were performed with the MCNPX code to determine homogenized fuel compositions in the lower and upper halves of each fuel element and to determine the resulting neutronic properties of the core. The accident analysis employed a model of the primary loop with the RELAP5 code. The model includes the primary pumps, shutdown pumps outlet valves, heat exchanger, fuel elements, and flow channels for both the six inner and twenty-four outer fuel elements. Evaluations were performed for the following accidents: (1) control rod withdrawal startup accident, (2) maximum reactivity insertion accident, (3) loss-of-flow accident resulting from loss of electrical power with an assumption of failure of shutdown cooling pumps, (4) loss-of-flow accident resulting from a primary pump seizure, and (5) loss-of-flow accident resulting from inadvertent throttling of a flow control valve. In addition, natural circulation cooling at low power operation was analyzed. The analysis shows that the conversion will not lead to significant changes in the safety analysis and the calculated minimum critical heat flux ratio and maximum clad temperature assure that there is adequate margin to fuel failure.

  14. BIOMASS ENERGY CONVERSION IN HAWAII

    E-Print Network [OSTI]

    Ritschard, Ronald L.

    2013-01-01

    Operations, vol. 2 of Biomass Energy (Stanford: StanfordPhotosynthethic Pathway Biomass Energy Production," ~c:_! _LBL-11902 UC-61a BIOMASS ENERGY CONVERSION IN HAWAII

  15. Power Electronics for Distributed Energy Systems and Transmission and Distribution Applications: Assessing the Technical Needs for Utility Applications

    SciTech Connect (OSTI)

    Tolbert, L.M.

    2005-12-21

    Power electronics can provide utilities the ability to more effectively deliver power to their customers while providing increased reliability to the bulk power system. In general, power electronics is the process of using semiconductor switching devices to control and convert electrical power flow from one form to another to meet a specific need. These conversion techniques have revolutionized modern life by streamlining manufacturing processes, increasing product efficiencies, and increasing the quality of life by enhancing many modern conveniences such as computers, and they can help to improve the delivery of reliable power from utilities. This report summarizes the technical challenges associated with utilizing power electronics devices across the entire spectrum from applications to manufacturing and materials development, and it provides recommendations for research and development (R&D) needs for power electronics systems in which the U.S. Department of Energy (DOE) could make a substantial impact toward improving the reliability of the bulk power system.

  16. OCEAN THERMAL ENERGY CONVERSION PROGRAMMATIC ENVIRONMENTAL ASSESSMENT

    SciTech Connect (OSTI)

    Sands, M.Dale

    1980-08-01

    Significant achievements in Ocean Thermal Energy Conversion (OTEC) technology have increased the probability of producing OTEC-derived power in this decade with subsequent large-scale commercialization to follow by the turn of the century. Under U.S. Department of Energy funding, Interstate Electronics has prepared an OTEC Programmatic Environmental Assessment (EA) that considers tne development, demonstration, and commercialization of OTEC power systems. The EA considers several tecnnological designs (open cycle and closed cycle), plant configurations (land-based, moored, and plantship), and power usages (baseload electricity and production of ammonia and aluminum). Potencial environmental impacts, health and safety issues, and a status update of international, federal, and state plans and policies, as they may influence OTEC deployments, are included.

  17. Non--Atomic Components of Data Flow Diagrams: Stores, Persistent Flows,

    E-Print Network [OSTI]

    Symanzik, Jürgen

    Non--Atomic Components of Data Flow Diagrams: Stores, Persistent Flows, and Tests for Empty Flows J NON--ATOMIC COMPONENTS OF DATA FLOW DIAGRAMS: STORES, PERSISTENT FLOWS, AND TESTS FOR EMPTY FLOWS of these common features of traditional Data Flow Diagrams elevates the expressive power of FDFD's, or whether

  18. HELIOPHYSICS II. ENERGY CONVERSION PROCESSES

    E-Print Network [OSTI]

    Hudson, Hugh

    with the term "solar flare" dominate our thinking about energy conversion from magnetic storage to other formsHELIOPHYSICS II. ENERGY CONVERSION PROCESSES edited by CAROLUS J. SCHRIJVER Lockheed Martin of a solar flare 11 2.3.1 Flare luminosity and mechanical energy 11 2.3.2 The impulsive phase (hard X

  19. Photovoltaic energy conversion The objective of this laboratory is for you to explore the science and engineering of the conversion of

    E-Print Network [OSTI]

    Braun, Paul

    Photovoltaic energy conversion Objective The objective of this laboratory is for you to explore the science and engineering of the conversion of light to electricity by photovoltaic devices. Preparation photovoltaic modules; reversebiased Si pin photodiode. · White light LED lamp; dc power supply; bread board

  20. High conversion hydrocracking process

    SciTech Connect (OSTI)

    Stine, L.O.; Reno, M.E.; Munro, W.H.; Hamper, S.J.

    1990-10-09

    This patent describes a process for hydrocracking a heavy hydrocarbon feed stream having a 10 percent boiling point above about 316{degrees} C. It comprises: passing the feedstream into a catalytic hydrocracking reaction zone in contact with hydrocracking catalyst comprising at least one metal selected from the group consisting of chromium, nickel, cobalt, platinum, palladium, tungsten and molybdenum, at a temperature above about 316{degrees} C. and a total pressure above 1480 kPa, the catalytic hydrocracking reaction zone operating at a feed stream conversion rate above 70 wt. percent with a hydrogen circulation rate in excess at 1777 m{sup 3}/m{sup 3}, to produce a reaction zone effluent stream, subjecting the reaction zone effluent stream to cooling and a vapor-liquid separation to yield a recycle hydrogen stream and a liquid phase stream, heating the liquid phase stream recovered from the vapor-liquid separation to vaporize at least 90 volume percent of the liquid phase stream, passing the heated and at least partially vaporized liquid phase stream to a fractionation zone wherein the stream is separated into at least a net bottoms stream, a heavy distillate stream, and at least one light distillate stream which is removed as the distillate product stream, removing all of the net bottoms stream from the process, and recycling substantially all of the heavy distillate stream to the catalytic hydrocracking zone.

  1. Energy conversion Subject Information

    E-Print Network [OSTI]

    Greff, Isabelle

    The purpose of this course is to study the different ways of converting energy resources into useful energy thermal energy system. Wave energy: available resource, Wave energy converters (Oscillating water column from geothermal resources. Efficiency of power production from geothermal resources, economic aspects

  2. Carbon aerogel electrodes for direct energy conversion

    DOE Patents [OSTI]

    Mayer, Steven T. (San Leandro, CA); Kaschmitter, James L. (Pleasanton, CA); Pekala, Richard W. (Pleasant Hill, CA)

    1997-01-01

    A direct energy conversion device, such as a fuel cell, using carbon aerogel electrodes, wherein the carbon aerogel is loaded with a noble catalyst, such as platinum or rhodium and soaked with phosphoric acid, for example. A separator is located between the electrodes, which are placed in a cylinder having plate current collectors positioned adjacent the electrodes and connected to a power supply, and a pair of gas manifolds, containing hydrogen and oxygen positioned adjacent the current collectors. Due to the high surface area and excellent electrical conductivity of carbon aerogels, the problems relative to high polarization resistance of carbon composite electrodes conventionally used in fuel cells are overcome.

  3. Carbon aerogel electrodes for direct energy conversion

    DOE Patents [OSTI]

    Mayer, S.T.; Kaschmitter, J.L.; Pekala, R.W.

    1997-02-11

    A direct energy conversion device, such as a fuel cell, using carbon aerogel electrodes is described, wherein the carbon aerogel is loaded with a noble catalyst, such as platinum or rhodium and soaked with phosphoric acid, for example. A separator is located between the electrodes, which are placed in a cylinder having plate current collectors positioned adjacent the electrodes and connected to a power supply, and a pair of gas manifolds, containing hydrogen and oxygen positioned adjacent the current collectors. Due to the high surface area and excellent electrical conductivity of carbon aerogels, the problems relative to high polarization resistance of carbon composite electrodes conventionally used in fuel cells are overcome. 1 fig.

  4. NREL: Biomass Research - Biochemical Conversion Capabilities

    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 on771/6/14 Contact:News Releases |NRELBiochemical Conversion

  5. Plasma-Hydrocarbon conversion - 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 WebQuantityBonneville Power Administration wouldMass mapSpeeding access| DepartmentPeerFederal FleetUpSmallHydrocarbon conversion Idaho

  6. Semiconductor nanowires for photovoltaic and photoelectrochemical energy conversion

    SciTech Connect (OSTI)

    Dasgupta, Neil; Yang, Peidong

    2013-01-23

    Semiconductor nanowires (NW) possess several beneficial properties for efficient conversion of solar energy into electricity and chemical energy. Due to their efficient absorption of light, short distances for minority carriers to travel, high surface-to-volume ratios, and the availability of scalable synthesis methods, they provide a pathway to address the low cost-to-power requirements for wide-scale adaptation of solar energy conversion technologies. Here we highlight recent progress in our group towards implementation of NW components as photovoltaic and photoelectrochemical energy conversion devices. An emphasis is placed on the unique properties of these one-dimensional (1D) structures, which enable the use of abundant, low-cost materials and improved energy conversion efficiency compared to bulk devices.

  7. Ocean Power (4 Activities) | Department of Energy

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

    our existing non-renewable resources. Ocean power is divided into three categories: wave energy, tidal energy, and ocean thermal energy conversion (OTEC) Systems. It is...

  8. Conversation View Outlook Web App User Guide

    E-Print Network [OSTI]

    Calgary, University of

    Conversation View Outlook Web App User Guide Email conversations that include multiple replies and sent messages can be viewed simultaneously using Conversation View. In Exchange 2010 Outlook Web App

  9. THIN-FILM FLOWS WITH WALL SLIP: AN ASYMPTOTIC ANALYSIS OF HIGHER ORDER GLACIER FLOW MODELS

    E-Print Network [OSTI]

    Fournier, John J.F.

    THIN-FILM FLOWS WITH WALL SLIP: AN ASYMPTOTIC ANALYSIS OF HIGHER ORDER GLACIER FLOW MODELS, Cambridge, CB3 0ET, UK) [Received 6 January 2009. Revise 6 November 2009] Summary Free-surface thin film of the flow. Conversely, membrane or `free film' models are appropriate in situations where there is rapid

  10. Tidal Conversion by Supercritical Topography

    E-Print Network [OSTI]

    Balmforth, Neil J.

    Calculations are presented of the rate of energy conversion of the barotropic tide into internal gravity waves above topography on the ocean floor. The ocean is treated as infinitely deep, and the topography consists of ...

  11. Plasmonic conversion of solar energy

    E-Print Network [OSTI]

    Clavero, Cesar

    2014-01-01

    Basic Research Needs for Solar Energy Utilization, BasicS. Pillai and M. A. Green, Solar Energy Materials and SolarPlasmonic conversion of solar energy César Clavero Plasma

  12. Conversion of formulae and quantities between unit systems

    E-Print Network [OSTI]

    Lehtinen, Nikolai G.

    Conversion of formulae and quantities between unit systems Nikolai G. Lehtinen March 1, 2002 1 cgs that to convert values, one should divide by the value in the third column, using c in SI system of units. E quantities don't change We use the fact that 0 contains the unit of charge (Coulomb) in 2 power and µ0

  13. Technical Market Analysis for Biochemical Conversion Presentation...

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

    Technical Market Analysis for Biochemical Conversion March 23, 2015 Biochemical Conversion Jim Collett and Mark Butcher PNNL This presentation does not contain any proprietary,...

  14. Unit Conversions and Formulas to Know

    E-Print Network [OSTI]

    rroames

    2007-12-06

    Math 139. Unit Conversions and Formulas to Memorize. Fall 2007. Unit Conversions to know: 1 foot = 12 inches. 1 centimeter = 10 millimeters. 1 yard = 3 feet.

  15. 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

  16. THE CONVERSION OF BIOMASS TO ETHANOL USING GEOTHERMAL ENERGY DERIVED FROM HOT DRY ROCK

    E-Print Network [OSTI]

    97505 THE CONVERSION OF BIOMASS TO ETHANOL USING GEOTHERMAL ENERGY DERIVED FROM HOT DRY ROCK of biomass to fuel ethanol is considerable. In addition, combining these two renewable energy resources of wedding an HDR geothermal power source to a biomass conversion process is flexibility, both in plant

  17. Definition of Power Converters

    E-Print Network [OSTI]

    Bordry, F

    2015-01-01

    The paper is intended to introduce power conversion principles and to define common terms in the domain. The concept s of sources and switches are defined and classified. From the basic laws of source interconnections, a generic method of power converter synthesis is presented. Some examples illustrate this systematic method. Finally, the commutation cell and soft commuta tion are introduced and discussedd.

  18. Maximizing Power Output in Homogeneous Charge Compression Ignition (HCCI) Engines and Enabling Effective Control of Combustion Timing

    E-Print Network [OSTI]

    Saxena, Samveg

    2011-01-01

    a HCCI engine for power generation”, Energy Conversion andbiogas HCCI engine for power generation , Applied Energy, inHCCI Engine for Power Generation, ASME IC Engine Conference,

  19. EERE PowerPoint 97-2004 Template: Green Version

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

    determine resource temperature that matched reported flow and power production - Modeled steam flow using turbine (choked flow) and assuming lowest reported well head temperature...

  20. Biomass Program 2007 Accomplishments - Thermochemical Conversion Platform

    SciTech Connect (OSTI)

    none,

    2009-10-27

    This document details the accomplishments of the Biomass Program Thermochemical Conversion Platform in 2007.

  1. Biomass Program 2007 Accomplishments - Biochemical Conversion Platform

    SciTech Connect (OSTI)

    none,

    2009-10-27

    This document details accomplishments of the Biomass Program Biochemical Conversion Platform accomplishments in 2007.

  2. Biochemical Conversion Pilot Plant (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-06-01

    This fact sheet provides information about Biochemical Conversion Pilot Plant capabilities and resources at NREL.

  3. Quantum-coupled single-electron thermal to electric conversion scheme

    E-Print Network [OSTI]

    Wu, D. M.

    Thermal to electric energy conversion with thermophotovoltaics relies on radiation emitted by a hot body, which limits the power per unit area to that of a blackbody. Microgap thermophotovoltaics take advantage of evanescent ...

  4. Ocean thermal energy conversion plants : experimental and analytical study of mixing and recirculation

    E-Print Network [OSTI]

    Jirka, Gerhard H.

    Ocean thermal energy conversion (OTEC) is a method of generating power using the vertical temperature gradient of the tropical ocean as an energy source. Experimental and analytical studies have been carried out to determine ...

  5. The Application of Frequency-Conversion Technology in Groundwater Source Heat Pump System Reconstruction 

    E-Print Network [OSTI]

    Dai, X.; Song, S.

    2006-01-01

    Deep well pump power is relatively ubiquitous in the groundwater heat pump air-conditioning system in some hotels in Hunan, and the heat pump usually meets the change of the load by throttling. Therefore, frequency conversion technology is proposed...

  6. Modeling and analysis of hybrid geothermal-solar thermal energy conversion systems

    E-Print Network [OSTI]

    Greenhut, Andrew David

    2010-01-01

    Innovative solar-geothermal hybrid energy conversion systems were developed for low enthalpy geothermal resources augmented with solar energy. The goal is to find cost-effective hybrid power cycles that take advantage of ...

  7. Design of passive decay heat removal system for the lead cooled flexible conversion ratio fast reactor

    E-Print Network [OSTI]

    Whitman, Joshua (Joshua J.)

    2007-01-01

    The lead-cooled flexible conversion ratio fast reactor shows many benefits over other fast-reactor designs; however, the higher power rating and denser primary coolant present difficulties for the design of a passive decay ...

  8. Copyright 2013 IEEE. Reprinted, with permission from: Line Limit Preserving Power System Equivalent

    E-Print Network [OSTI]

    system. Line limits are a fundamental part of the formulation for Power Flow problems, Optimal Power Flow (OPF) problems and Security-Constrained Optimal Power Flow (SCOPF) problems for electric power systems generation or loads

  9. Power management circuits for ultra-low power systems

    E-Print Network [OSTI]

    El-Damak, Dina Reda

    2015-01-01

    Power management circuits perform a wide range of vital tasks for electronic systems including DC-DC conversion, energy harvesting, battery charging and protection as well as dynamic voltage scaling. The impact of the ...

  10. Anisotropic flow

    E-Print Network [OSTI]

    S. A. Voloshin

    2002-11-20

    Recent experimental results on directed and elliptic flow, theoretical developments, and new techniques for anisotropic flow analysis are reviewed.

  11. Magnet Technology for Power Converters: Nanocomposite Magnet Technology for High Frequency MW-Scale Power Converters

    SciTech Connect (OSTI)

    2012-02-27

    Solar ADEPT Project: CMU is developing a new nanoscale magnetic material that will reduce the size, weight, and cost of utility-scale PV solar power conversion systems that connect directly to the grid. Power converters are required to turn the energy that solar power systems create into useable energy for the grid. The power conversion systems made with CMU’s nanoscale magnetic material have the potential to be 150 times lighter and significantly smaller than conventional power conversion systems that produce similar amounts of power.

  12. Use of a Geothermal-Solar Hybrid Power Plant to Mitigate Declines in Geothermal Resource Productivity

    SciTech Connect (OSTI)

    Dan Wendt; Greg Mines

    2014-09-01

    Many, if not all, geothermal resources are subject to decreasing productivity manifested in the form of decreasing brine temperature, flow rate, or both during the life span of the associated power generation project. The impacts of resource productivity decline on power plant performance can be significant; a reduction in heat input to a power plant not only decreases the thermal energy available for conversion to electrical power, but also adversely impacts the power plant conversion efficiency. The reduction in power generation is directly correlated to a reduction in revenues from power sales. Further, projects with Power Purchase Agreement (PPA) contracts in place may be subject to significant economic penalties if power generation falls below the default level specified. A potential solution to restoring the performance of a power plant operating from a declining productivity geothermal resource involves the use of solar thermal energy to restore the thermal input to the geothermal power plant. There are numerous technical merits associated with a renewable geothermal-solar hybrid plant in which the two heat sources share a common power block. The geo-solar hybrid plant could provide a better match to typical electrical power demand profiles than a stand-alone geothermal plant. The hybrid plant could also eliminate the stand-alone concentrated solar power plant thermal storage requirement for operation during times of low or no solar insolation. This paper identifies hybrid plant configurations and economic conditions for which solar thermal retrofit of a geothermal power plant could improve project economics. The net present value of the concentrated solar thermal retrofit of an air-cooled binary geothermal plant is presented as functions of both solar collector array cost and electricity sales price.

  13. Recirculation in multiple wave conversions

    SciTech Connect (OSTI)

    Brizard, A. J. [Department of Chemistry and Physics, Saint Michael's College, Colchester, Vermont 05439 (United States); Kaufman, A. N. [Department of Physics and Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720 (United States); Tracy, E. R. [Department of Physics, College of William and Mary, Williamsburg, Virginia 23187-8795 (United States)

    2008-08-15

    A one-dimensional multiple wave-conversion model is constructed that allows energy recirculation in ray phase space. Using a modular eikonal approach, the connection coefficients for this model are calculated by ray phase-space methods. Analytical results (confirmed numerically) show that all connection coefficients exhibit interference effects that depend on an interference phase, calculated from the coupling constants and the area enclosed by the intersecting rays. This conceptual model, which focuses on the topology of intersecting rays in phase space, is used to investigate how mode conversion between primary and secondary waves is modified by the presence of a tertiary wave.

  14. MUTUAL CONVERSION SOLAR AND SIDEREAL

    E-Print Network [OSTI]

    Roegel, Denis

    TABLES FOR THE MUTUAL CONVERSION OF SOLAR AND SIDEREAL TIME BY EDWARD SANG, F.R.S.E. EDINBURGH in the third example. Sang converts 3.27 seconds of solar time into 3.26 seconds of sidereal time. But sidereal time elapses faster than solar time, and the correct value is 3.28 sec- onds. In the fourth example

  15. Rationality and Conversation: A Thesis on Grice’s Theory of Conversation 

    E-Print Network [OSTI]

    Schoolfield, Matthew D

    2007-11-27

    H. P. Grice first presented his theory of conversational implicature in “Logic and Conversation.” This theory is comprised of conversational maxims that are based on the Cooperative Principle. Since then, it has become ...

  16. Free-piston Stirling technology for space power

    SciTech Connect (OSTI)

    Slaby, J.G.

    1994-09-01

    An overview is presented of the NASA Lewis Research Center free-piston Stirling engine activities directed toward space power. This work is being carried out under NASA`s new Civil Space Technology Initiative (CSTI). The overall goal of CSTI`s High Capacity Power element is to develop the technology base needed to meet the long duration, high capacity power requirements for future NASA space missions. The Stirling cycle offers an attractive power conversion concept for space power needs. Discussed in this paper is the completion of the Space Power Demonstrator Engine (SPDE) testing - culminating in the generation of 25 kW of engine power from a dynamically-balanced opposed-piston Stirling engine at a temperature ratio of 2.0. Engine efficiency was approximately 22 percent. The SPDE recently has been divided into two separate single-cylinder engines, called Space Power Research Engines (SPRE), that now serve as test beds for the evaluation of key technology disciplines. These disciplines include hydrodynamic gas bearings, high-efficiency linear alternators, space qualified heat pipe heat exchangers, oscillating flow code validation, and engine loss understanding. The success of the SPDE at 650 K has resulted in a more ambitious Stirling endeavor - the design, fabrication, test and evaluation of a designed-for-space 25 kW per cylinder Stirling Space Engine (SSE). The SSE will operate at a hot metal temperature of 1050 K using superalloy materials. This design is a low temperature confirmation of the 1300 K design. It is the 1300 K free-piston Stirling power conversion system that is the ultimate goal; to be used in conjunction with the SP-100 reactor. The approach to this goal is in three temperature steps. However, this paper concentrates on the first two phases of this program - the 650 K SPDE and the 1050 K SSE.

  17. Thermophotovoltaics : shaping the flow of thermal radiation

    E-Print Network [OSTI]

    ?elanovi?, Ivan

    2006-01-01

    This thesis explores the modeling, design, and optimization of photonic crystals as spectral control components for high-performance thermophotovoltaic (TPV) power conversion. In particular, we focus on the use of ...

  18. Energy Conversion and Storage Program: 1992 Annual report

    SciTech Connect (OSTI)

    Cairns, E.J.

    1993-06-01

    This report is the 1992 annual progress report for the Energy Conversion and Storage Program, a part of the Energy and Environment Division of the Lawrence Berkeley Laboratory. Work described falls into three broad areas: electrochemistry; chemical applications; and materials applications. The Energy Conversion and Storage Program applies principles of chemistry and materials science to solve problems in several areas: (1) production of new synthetic fuels, (2) development of high-performance rechargeable batteries and fuel cells, (3) development of advanced thermochemical processes for energy conversion, (4) characterization of complex chemical processes and chemical species, and (5) study and application of novel materials for energy conversion and transmission. Projects focus on transport-process principles, chemical kinetics, thermodynamics, separation processes, organic and physical chemistry, novel materials, and advanced methods of analysis. Electrochemistry research aims to develop advanced power systems for electric vehicle and stationary energy storage applications. Chemical applications research includes topics such as separations, catalysis, fuels, and chemical analyses. Included in this program area are projects to develop improved, energy-efficient methods for processing product and waste streams from synfuel plants, coal gasifiers, and biomass conversion processes. Materials applications research includes evaluation of the properties of advanced materials, as well as development of novel preparation techniques. For example, techniques such as sputtering, laser ablation, and poised laser deposition are being used to produce high-temperature superconducting films.

  19. High frequency AC power converter for low voltage circuits

    E-Print Network [OSTI]

    Salazar, Nathaniel Jay Tobias

    2012-01-01

    This thesis presents a novel AC power delivery architecture that is suitable for VHF frequency (50-100MHz) polyphase AC/DC power conversion in low voltage integrated circuits. A complete AC power delivery architecture was ...

  20. Open cycle ocean thermal energy conversion system

    DOE Patents [OSTI]

    Wittig, J. Michael (West Goshen, PA)

    1980-01-01

    An improved open cycle ocean thermal energy conversion system including a flash evaporator for vaporizing relatively warm ocean surface water and an axial flow, elastic fluid turbine having a vertical shaft and axis of rotation. The warm ocean water is transmitted to the evaporator through a first prestressed concrete skirt-conduit structure circumferentially situated about the axis of rotation. The unflashed warm ocean water exits the evaporator through a second prestressed concrete skirt-conduit structure located circumferentially about and radially within the first skirt-conduit structure. The radially inner surface of the second skirt conduit structure constitutes a cylinder which functions as the turbine's outer casing and obviates the need for a conventional outer housing. The turbine includes a radially enlarged disc element attached to the shaft for supporting at least one axial row of radially directed blades through which the steam is expanded. A prestressed concrete inner casing structure of the turbine has upstream and downstream portions respectively situated upstream and downstream from the disc element. The radially outer surfaces of the inner casing portions and radially outer periphery of the axially interposed disc cooperatively form a downwardly radially inwardly tapered surface. An annular steam flowpath of increasing flow area in the downward axial direction is radially bounded by the inner and outer prestressed concrete casing structures. The inner casing portions each include a transversely situated prestressed concrete circular wall for rotatably supporting the turbine shaft and associated structure. The turbine blades are substantially radially coextensive with the steam flowpath and receive steam from the evaporator through an annular array of prestressed concrete stationary vanes which extend between the inner and outer casings to provide structural support therefor and impart a desired flow direction to the steam.

  1. Microsoft PowerPoint - Pillon Climate Change and the Need for...

    Office of Environmental Management (EM)

    use, improve conversion efficiency, and operate independently of the power grid Microgrids can supply highly-reliable power during times of natural disaster Energy storage...

  2. Ocean Power Technologies (TRL 5 6 System) - PB500, 500 kW Utility...

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

    technologiesinchart.ppt More Documents & Publications Advanced, High Power, Next Scale, Wave Energy Conversion Device Ocean Power Technologies (TRL 7 8 System) - Reedsport PB150...

  3. 7-29 A coal-burning power plant produces 300 MW of power. The amount of coal consumed during a one-day period and the rate of air flowing through the furnace are to be determined.

    E-Print Network [OSTI]

    Bahrami, Majid

    7-11 7-29 A coal-burning power plant produces 300 MW of power. The amount of coal consumed during The power plant operates steadily. 2 The kinetic and potential energy changes are zero. Properties The heating value of the coal is given to be 28,000 kJ/kg. Analysis (a) The rate and the amount of heat inputs

  4. Free Flow Energy (TRL 1 2 3 Component) - Design and Development...

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

    Free Flow Energy (TRL 1 2 3 Component) - Design and Development of a Cross-Platform Submersible Generator Optimized for the Conditions of Current Energy Conversion Free Flow Energy...

  5. Weather Ready Nation: A Vital Conversation on

    E-Print Network [OSTI]

    Weather Ready Nation: A Vital Conversation on Tornadoes and Severe Weather A Community Report March;WeatherReady Nation: A Vital Conversation on Tornadoes and Severe Weather Report from the December 2011

  6. Power transaction issues in deregulated power systems 

    E-Print Network [OSTI]

    Roycourt, Henrik

    2000-01-01

    is to review the power flow problem and the newly emerging concept of Available Transfer Capability (ATC) / Total Transfer Capability (TTC). Secondly, it aims at reviewing and implementing in the Matlab environment a technique for tracing the contributions...

  7. Optomechanical conversion by mechanical turbines

    E-Print Network [OSTI]

    Kneževi?, Miloš; Warner, Mark

    2014-10-30

    has mov- ing parts gives it a disadvantage over conventional photo- voltaics, though rubber is highly durable and tough — for instance car tyres survive long use in harsh, abra- sive conditions. Another difficulty, that could perhaps be solved... ’effect du frottement dans l’equilibre,” Mem. Acad. Sci. , pp. 265 (1762). 7[14] L. R. G. Treloar, The Physics of Rubber Elasticity (Ox- ford University Press, Oxford, 2005). [15] M. Knez?evic´ and M. Warner, “Photoferroelectric solar to electrical conversion...

  8. The National Conversion Pilot Project

    SciTech Connect (OSTI)

    Roberts, A.V.

    1995-12-31

    The National Conversion Pilot Project (NCPP) is a recycling project under way at the U.S. Department of Energy (DOE) Rocky Flats Environmental Technology Site (RFETS) in Colorado. The recycling aim of the project is threefold: to reuse existing nuclear weapon component production facilities for the production of commercially marketable products, to reuse existing material (uranium, beryllium, and radioactively contaminated scrap metals) for the production of these products, and to reemploy former Rocky Flats workers in this process.

  9. Thermochemical Conversion | 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 FuelsofProgram: Report15 MeetingDevelopmentDepartmentof EnergyTheConversion

  10. Vehicle Technologies Office: Power Electronics | Department of...

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

    Office (VTO) is supporting research to lower the cost and improve the performance of power electronics. Vehicle power electronics primarily process and control the flow of...

  11. An Energy-Based Approach to Power System Analysis

    E-Print Network [OSTI]

    Caliskan, Sina Yamac

    2015-01-01

    loads, Electrical Power and Energy Systems, Vol. 8, Issue 1,equation, Electrical Power & Energy Systems, Vol. 3, No. 3,In contemporary power systems, energy flows from the

  12. OCEAN THERMAL ENERGY CONVERSION: AN OVERALL ENVIRONMENTAL ASSESSMENT

    E-Print Network [OSTI]

    Sands, M.Dale

    2013-01-01

    M.D. (editor). 1980. Ocean Thermal Energy Conversion Draft1980 :. i l OCEAN THERMAL ENERGY CONVERSION: ENVIRONMENTALDevelopment Plan. Ocean Thermal Energy Conversion. U.S. DOE

  13. DRAFT. ENVIRONMENTAL ASSESSMENT OCEAN THERMAL ENERGY CONVERSION (OTEC) PILOT PLANTS

    E-Print Network [OSTI]

    Sullivan, S.M.

    2014-01-01

    1979. Commercial ocean thermal energy conversion ( OTEC)field of ocean thermal energy conversion discharges. I~. L.II of the Sixth Ocean Thermal Energy conversion Conference.

  14. ENVIRONMENTAL ASSESSMENT OCEAN THERMAL ENERGY CONVERSION (OTEC) PILOT PLANTS

    E-Print Network [OSTI]

    Sullivan, S.M.

    2014-01-01

    1979. Commercial ocean thermal energy conversion (OTEC)of the Fifth Ocean Thermal Energy Conversion Conference,Sands. 1980. Ocean thermal energy conversion (OTEC) pilot

  15. Controlling Energy Costs with Coal Conversion 

    E-Print Network [OSTI]

    Sadowski, R. S.; von Hippel, C. S.

    1984-01-01

    ~~~==~~tt~~~Fe:,edwater FD Blower Figure 6 For the eight years of its existence, WEI's fluid bed emphasis has been on the industrial burning of coal. Fluidized bed burning of coal offers the industrial user a means of burning our cheapest and most...:======9\\===::::? times that of the ash flow in a lower velocity system and of course such systems require a considerable amount of electrical power. Finally, circulating beds have to date had limited experience burning coal. Many (if not all) require support fuel...

  16. Photonic Crystals for Enhancing Thermophotovoltaic Energy Conversion

    SciTech Connect (OSTI)

    LIN, SHAWN-YU; FLEMING, JAMES G.; MORENO, JOSEPH A.

    2003-03-01

    Thermophotovoltaics (TPV) converts the radiant energy of a thermal source into electrical energy using photovoltaic cells. TPV has a number of attractive features, including: fuel versatility (nuclear, fossil, solar, etc.), quiet operation, low maintenance, low emissions, light weight, high power density, modularity, and possibility for cogeneration of heat and electricity. Some of these features are highly attractive for military applications (Navy and Army). TPV could also be used for distributed power and automotive applications wherever fuel cells, microturbines, or cogeneration are presently being considered if the efficiencies could be raised to around 30%. This proposal primarily examine approaches to improving the radiative efficiency. The ideal irradiance for the PV cell is monochromatic illumination at the bandgap. The photonic crystal approach allows for the tailoring of thermal emission spectral bandwidth at specific wavelengths of interest. The experimental realization of metallic photonic crystal structures, the optical transmission, reflection and absorption characterization of it have all been carried out in detail and will be presented next. Additionally, comprehensive models of TPV conversion has been developed and applied to the metallic photonic crystal system.

  17. High resolution A/D conversion based on piecewise conversion at lower resolution

    DOE Patents [OSTI]

    Terwilliger, Steve (Albuquerque, NM)

    2012-06-05

    Piecewise conversion of an analog input signal is performed utilizing a plurality of relatively lower bit resolution A/D conversions. The results of this piecewise conversion are interpreted to achieve a relatively higher bit resolution A/D conversion without sampling frequency penalty.

  18. An Energy-Flow Model for Self-Powered Routers in Rural Mesh Networks and its Application for Energy-Aware Routing 

    E-Print Network [OSTI]

    Pejovic, Veljko; Belding, Elizabeth; Marina, Mahesh

    Self-powered wireless mesh networks have gained popularity as a cheap alternative for providing Internet access in many rural areas of the developed and, especially, the developing world. The quality of service that ...

  19. A COMPUTATIONAL ANALYSIS OF THE OPTIMAL POWER FLOW PROBLEM Baha Alzalg, Catalina Anghel, Wenying Gan, Qing Huang, Mustazee Rahman, Alex Shum

    E-Print Network [OSTI]

    under these contingencies was exemplified by the blackout in the North American power grid during 2003. The reason for the blackout was a failure of only a handful of contingencies in the network [8

  20. One-dimensional full wave simulation on XB mode conversion in electron cyclotron heating

    SciTech Connect (OSTI)

    Kim, S. H., E-mail: shkim95@kaeri.re.kr [Korea Atomic Energy Research Institute, Daejeon 305-353 (Korea, Republic of); Lee, H. Y.; Jo, J. G.; Hwang, Y. S. [Seoul National University, Seoul 151-742 (Korea, Republic of)

    2014-06-15

    The XB mode conversion in electron cyclotron resonance frequency heating has been studied in detail through 1D full wave simulation. The field pattern depends on the density scale length, and the wave absorption near upper hybrid resonance is maximized beyond the R(X) mode cutoff density for optimized density scale length. The simulated mode conversion efficiency has been compared with that of an analytic formula, showing good agreements except for the phase dependent term of the X wave. The mode conversion efficiency is calculated for oblique injections as well, and it is found that the efficiency decreases as the injection angles increases. Short magnetic field scale length is confirmed to relax the short density scale length condition maximizing the XB mode conversion efficiency. Finally, the simulation code is used to analyze the mode conversion and power absorption of a pre-ionization plasma in versatile experiment spherical torus.

  1. A Framework for Reliability and Performance Assessment of Wind Energy Conversion Systems

    E-Print Network [OSTI]

    Liberzon, Daniel

    penetration of wind-based generation. According to the U.S. Department of Energy, achieving 20% of wind power hinder the widespread penetration of wind-based power generation [2]. These are i) the impact of wind1 A Framework for Reliability and Performance Assessment of Wind Energy Conversion Systems

  2. Sandia Energy - Energy Conversion Efficiency

    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 of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDid youOxygen GenerationTechnologiesEnergy Conversion Efficiency Home

  3. Biochemical Conversion | 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 Fuels DataEnergy Webinar:I DueBETO Quiz -Technologies forBig SavingsConversion

  4. Wind Power

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

    Wind Power Bioenergy Power Systems Wind Power Wind Power Main Page Outreach Programs Image Gallery FAQs Links Software Hydro Power INL Home Wind Power Introduction The Wind Power...

  5. Conversion Preliminary Safety Analysis Report for the NIST Research Reactor

    SciTech Connect (OSTI)

    Diamond, D. J.; Baek, J. S.; Hanson, A. L.; Cheng, L-Y; Brown, N.; Cuadra, A.

    2015-01-30

    The NIST Center for Neutron Research (NCNR) is a reactor-laboratory complex providing the National Institute of Standards and Technology (NIST) and the nation with a world-class facility for the performance of neutron-based research. The heart of this facility is the NIST research reactor (aka NBSR); a heavy water moderated and cooled reactor operating at 20 MW. It is fueled with high-enriched uranium (HEU) fuel elements. A Global Threat Reduction Initiative (GTRI) program is underway to convert the reactor to low-enriched uranium (LEU) fuel. This program includes the qualification of the proposed fuel, uranium and molybdenum alloy foil clad in an aluminum alloy, and the development of the fabrication techniques. This report is a preliminary version of the Safety Analysis Report (SAR) that would be submitted to the U.S. Nuclear Regulatory Commission (NRC) for approval prior to conversion. The report follows the recommended format and content from the NRC codified in NUREG-1537, “Guidelines for Preparing and Reviewing Applications for the Licensing of Non-power Reactors,” Chapter 18, “Highly Enriched to Low-Enriched Uranium Conversions.” The emphasis in any conversion SAR is to explain the differences between the LEU and HEU cores and to show the acceptability of the new design; there is no need to repeat information regarding the current reactor that will not change upon conversion. Hence, as seen in the report, the bulk of the SAR is devoted to Chapter 4, Reactor Description, and Chapter 13, Safety Analysis.

  6. Energy Conversion and Storage Program. 1990 annual report

    SciTech Connect (OSTI)

    Cairns, E.J.

    1992-03-01

    The Energy Conversion and Storage Program applies chemistry and materials science principles to solve problems in (1) production of new synthetic fuels, (2) development of high-performance rechargeable batteries and fuel cells, (3) development of advanced thermochemical processes for energy conversion, (4) characterization of complex chemical processes, and (5) application of novel materials for energy conversion and transmission. Projects focus on transport-process principles, chemical kinetics, thermodynamics, separation processes, organic and physical chemistry, novel materials, and advanced methods of analysis. Electrochemistry research aims to develop advanced power systems for electric vehicle and stationary energy storage applications. Topics include identification of new electrochemical couples for advanced rechargeable batteries, improvements in battery and fuel-cell materials, and the establishment of engineering principles applicable to electrochemical energy storage and conversion. Chemical Applications research includes topics such as separations, catalysis, fuels, and chemical analyses. Included in this program area are projects to develop improved, energy-efficient methods for processing waste streams from synfuel plants and coal gasifiers. Other research projects seek to identify and characterize the constituents of liquid fuel-system streams and to devise energy-efficient means for their separation. Materials Applications research includes the evaluation of the properties of advanced materials, as well as the development of novel preparation techniques. For example, the use of advanced techniques, such as sputtering and laser ablation, are being used to produce high-temperature superconducting films.

  7. 600-T Magnetic Fields due to Cold Electron Flow in a simple Cu-Coil irradiated by High Power Laser pulses

    E-Print Network [OSTI]

    Zhu, Baojun; Yuan, Dawei; Li, Yanfei; Li, Fang; Liao, Guoqian; Zhao, Jiarui; Zhong, Jiayong; Xue, Feibiao; Wei, Huigang; Zhang, Kai; Han, Bo; Pei, Xiaoxing; Liu, Chang; Zhang, Zhe; Wang, Weimin; Zhu, Jianqiang; Zhao, Gang; Zhang, Jie

    2015-01-01

    A new simple mechanism due to cold electron flow to produce strong magnetic field is proposed. A 600-T strong magnetic field is generated in the free space at the laser intensity of 5.7x10^15 Wcm^-2. Theoretical analysis indicates that the magnetic field strength is proportional to laser intensity. Such a strong magnetic field offers a new experimental test bed to study laser-plasma physics, in particular, fast-ignition laser fusion research and laboratory astrophysics.

  8. Explorations of Novel Energy Conversion and Storage Systems

    E-Print Network [OSTI]

    Duffin, Andrew Mark

    2010-01-01

    Energy Conversion and Storage Systems By Andrew Mark DuffinEnergy Conversion and Storage Systems by Andrew Mark Duffin

  9. 2011 Biomass Program Platform Peer Review: Thermochemical Conversion...

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

    Thermochemical Conversion 2011 Biomass Program Platform Peer Review: Thermochemical Conversion "This document summarizes the recommendations and evaluations provided by an...

  10. Efficient mode conversion in guiding structures with longitudinal modulation of nonlinearity

    E-Print Network [OSTI]

    Vysloukh, Victor A; Staliunas, Kestutis

    2015-01-01

    We describe power-dependent dynamics of conversion of the guided modes of various guiding structures due to nearly resonant longitudinal modulation of the nonlinear coefficient of the medium. It is shown that the control of the energy exchange integrals, as well as of the input weights of the interacting modes is especially crucial for efficient mode conversion in the setting considered here. Complex dynamics of conversion incorporates various scenarios, including non-harmonic oscillations of the energy weights, which mimics Jacoby elliptical functions.

  11. Reliability Evaluation of Electric Power Generation Systems with Solar Power 

    E-Print Network [OSTI]

    Samadi, Saeed

    2013-11-08

    Conventional power generators are fueled by natural gas, steam, or water flow. These generators can respond to fluctuating load by varying the fuel input that is done by a valve control. Renewable power generators such as ...

  12. Frequency-selective Power Transducers "Hexagonal Ferrite Resonator--Semiconductor Element"

    E-Print Network [OSTI]

    Koledintseva, Marina Y.

    -effect voltage. The conversion co- efficient of a transducer is analyzed using the power balance equation. Some contains a primary measuring transducer and a secondary processing/display unit. A primary transducer frequency selectivity of power conversion. 2. Mathematical Model for the Conversion Coefficient

  13. Resistance Compression Networks for Radio-Frequency Power Conversion

    E-Print Network [OSTI]

    Han, Yehui

    A limitation of many high-frequency resonant inverter topologies is their high sensitivity to loading conditions. This paper introduces a new class of matching networks that greatly reduces the load sensitivity of resonant ...

  14. Automotive Waste Heat Conversion to Power Program | 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:FinancingPetroleum Based Fuels Research atDepartmentAuditsDepartment of(TEG)of Energy1 DOE

  15. Automotive Waste Heat Conversion to Power Program | 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:FinancingPetroleum Based Fuels Research atDepartmentAuditsDepartment of(TEG)of Energy1 DOE0 DOE

  16. Automotive Waste Heat Conversion to Power Program | 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:FinancingPetroleum Based Fuels Research atDepartmentAuditsDepartment of(TEG)of Energy1 DOE0

  17. Sandia Energy - thermo-electric power conversion technology

    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 MagnetizationTransportationVideosEnergy StaffWindcwdd

  18. Natural Regulation of Energy Flow in a Green Quantum Photocell

    E-Print Network [OSTI]

    Arp, Trevor B; Aji, Vivek; Gabor, Nathaniel M

    2015-01-01

    Manipulating the flow of energy in nanoscale and molecular photonic devices is of both fundamental interest and central importance for applications in light harvesting optoelectronics. Under erratic solar irradiance conditions, unregulated power fluctuations in a light harvesting photocell lead to inefficient energy storage in conventional solar cells and potentially fatal oxidative damage in photosynthesis. Here, we show that regulation against these fluctuations arises naturally within a two-channel quantum heat engine photocell, thus enabling the efficient conversion of varying incident solar spectrum at Earth's surface. Remarkably, absorption in the green portion of the spectrum is avoided, as it provides no inherent regulatory benefit. Our findings illuminate a quantum structural origin of regulation, provide a novel optoelectronic design strategy, and may elucidate the link between photoprotection in photosynthesis and the predominance of green plants on Earth.

  19. Natural Regulation of Energy Flow in a Green Quantum Photocell

    E-Print Network [OSTI]

    Trevor B. Arp; Yafis Barlas; Vivek Aji; Nathaniel M. Gabor

    2015-08-26

    Manipulating the flow of energy in nanoscale and molecular photonic devices is of both fundamental interest and central importance for applications in light harvesting optoelectronics. Under erratic solar irradiance conditions, unregulated power fluctuations in a light harvesting photocell lead to inefficient energy storage in conventional solar cells and potentially fatal oxidative damage in photosynthesis. Here, we show that regulation against these fluctuations arises naturally within a two-channel quantum heat engine photocell, thus enabling the efficient conversion of varying incident solar spectrum at Earth's surface. Remarkably, absorption in the green portion of the spectrum is avoided, as it provides no inherent regulatory benefit. Our findings illuminate a quantum structural origin of regulation, provide a novel optoelectronic design strategy, and may elucidate the link between photoprotection in photosynthesis and the predominance of green plants on Earth.

  20. Approaching 10% Conversion Efficiency Using Tandem Organic Photovoltaic Cells with Enhanced Optical Coupling: Final Report, October 2004 - December 2007

    SciTech Connect (OSTI)

    Forrest, S.

    2008-08-01

    To find routes to achieving nearly 10% power conversion efficiency based on a new generation of organic photovoltaic cells using vapor-deposited, small-molecular-weight organic materials.

  1. A novel thermomechanical energy conversion cycle Ian M. McKinley, Felix Y. Lee, Laurent Pilon

    E-Print Network [OSTI]

    Pilon, Laurent

    of waste mechanical energy include fluid flow, household appliances, industrial equipment, motor vehiclesA novel thermomechanical energy conversion cycle Ian M. McKinley, Felix Y. Lee, Laurent Pilon of a novel cycle converting thermal and mechanical energy directly into electrical energy. The new cycle

  2. Subcooled flow boiling of fluorocarbons

    E-Print Network [OSTI]

    Murphy, Richard Walter

    1971-01-01

    A study was conducted of heat transfer and hydrodynamic behavior for subcooled flow boiling of Freon-113, one of a group of fluorocarbons suitable for use in cooling of high-power-density electronic components. Problems ...

  3. Power inverters

    DOE Patents [OSTI]

    Miller, David H. (Redondo Beach, CA); Korich, Mark D. (Chino Hills, CA); Smith, Gregory S. (Woodland Hills, CA)

    2011-11-15

    Power inverters include a frame and a power module. The frame has a sidewall including an opening and defining a fluid passageway. The power module is coupled to the frame over the opening and includes a substrate, die, and an encasement. The substrate includes a first side, a second side, a center, an outer periphery, and an outer edge, and the first side of the substrate comprises a first outer layer including a metal material. The die are positioned in the substrate center and are coupled to the substrate first side. The encasement is molded over the outer periphery on the substrate first side, the substrate second side, and the substrate outer edge and around the die. The encasement, coupled to the substrate, forms a seal with the metal material. The second side of the substrate is positioned to directly contact a fluid flowing through the fluid passageway.

  4. US energy flow, 1991

    SciTech Connect (OSTI)

    Borg, I.Y.; Briggs, C.K.

    1992-06-01

    Trends in energy consumption and assessment of energy sources are discussed. Specific topics discussed include: energy flow charts; comparison of energy use with 1990 and earlier years; supply and demand of fossil fuels (oils, natural gas, coal); electrical supply and demand; and nuclear power.

  5. ENERGY FLOWS CLIMATE CHANGE

    E-Print Network [OSTI]

    Schwartz, Stephen E.

    ENERGY FLOWS FORCINGS CLIMATE CHANGE A REALLY TOUGH PROBLEM Stephen E. Schwartz, BNL, 7-20-11 www average temperature 15°C or 59°F #12;ATMOSPHERIC RADIATION Power per area Energy per time per area Unit" temperature to radiative flux. #12;GLOBAL ENERGY BALANCE Global and annual average energy fluxes in watts per

  6. Mesofluidic magnetohydrodynamic power generation

    E-Print Network [OSTI]

    Fucetola, Jay J

    2012-01-01

    Much of the previous research into magnetohydrodynamics has involved large-scale systems. This thesis explores the miniaturization and use of devices to convert the power dissipated within an expanding gas flow into ...

  7. Planning Document for an NBSR Conversion Safety Analysis Report

    SciTech Connect (OSTI)

    Diamond D. J.; Baek J.; Hanson, A.L.; Cheng, L-Y.; Brown, N.; Cuadra, A.

    2013-09-25

    The NIST Center for Neutron Research (NCNR) is a reactor-laboratory complex providing the National Institute of Standards and Technology (NIST) and the nation with a world-class facility for the performance of neutron-based research. The heart of this facility is the National Bureau of Standards Reactor (NBSR). The NBSR is a heavy water moderated and cooled reactor operating at 20 MW. It is fueled with high-enriched uranium (HEU) fuel elements. A Global Threat Reduction Initiative (GTRI) program is underway to convert the reactor to low-enriched uranium (LEU) fuel. This program includes the qualification of the proposed fuel, uranium and molybdenum alloy foil clad in an aluminum alloy, and the development of the fabrication techniques. This report is a planning document for the conversion Safety Analysis Report (SAR) that would be submitted to, and approved by, the Nuclear Regulatory Commission (NRC) before the reactor could be converted.This report follows the recommended format and content from the NRC codified in NUREG-1537, “Guidelines for Preparing and Reviewing Applications for the Licensing of Non-power Reactors,” Chapter 18, “Highly Enriched to Low-Enriched Uranium Conversions.” The emphasis herein is on the SAR chapters that require significant changes as a result of conversion, primarily Chapter 4, Reactor Description, and Chapter 13, Safety Analysis. The document provides information on the proposed design for the LEU fuel elements and identifies what information is still missing. This document is intended to assist ongoing fuel development efforts, and to provide a platform for the development of the final conversion SAR. This report contributes directly to the reactor conversion pillar of the GTRI program, but also acts as a boundary condition for the fuel development and fuel fabrication pillars.

  8. Natural gas/diesel conversions - the outlook

    SciTech Connect (OSTI)

    Fiore, V.B.; Joyce, T.J.

    1986-01-01

    High conversion costs and technical inadequacies of available equipment have limited diesel to compressed natural gas (CNG) conversions, a process which can use either fumigation, pilot oil injection, or spark-ignition for vehicle ignition. An overview of Gas Research Institute conversion research projects includes a summary of major problems associated with performance, cost, and reliability of the systems. A summary table identifies projects by organization and location, then provides project objectives, funding, future plans, and comments where the information is available.

  9. Covariance statistics of turbulence velocity components for wind-energy-conversion system design-homogeneous, isotropic case

    SciTech Connect (OSTI)

    Fichtl, G.H.

    1983-09-01

    When designing a wind energy converison system (WECS), it may be necessary to take into account the distribution of wind across the disc of rotation. The specific engineering applications include structural strength, fatigue, and control. This wind distribution consists of two parts, namely that associated with the mean wind profile and that associated with the turbulence velocity fluctuation field. The work reported herein is aimed at the latter, namely the distribution of turbulence velocity fluctuations across the WECS disk of rotation. A theory is developed for the two-time covariance matrix for turbulence velocity vector components for wind energy conversion system (WECS) design. The theory is developed for homogeneous and iotropic turbulance with the assumption that Taylor's hypothesis is valid. The Eulerian turbulence velocity vector field is expanded about the hub of the WECS. Formulae are developed for the turbulence velocity vector component covariance matrix following the WECS blade elements. It is shown that upon specification of the turbulence energy spectrum function and the WECS rotation rate, the two-point, two-time covariance matrix of the turbulent flow relative to the WECS bladed elements is determined. This covariance matrix is represented as the sum of nonstationary and stationary contributions. Generalized power spectral methods are used to obtain two-point, double frequency power spectral density functions for the turbulent flow following the blade elements. The Dryden turbulence model is used to demonstrate the theory. A discussion of linear system response analysis is provided to show how the double frequency turbulence spectra might be used to calculate response spectra of a WECS to turbulent flow. Finally the spectrum of the component of turbulence normal to the WECS disc of rotation, following the blade elements, is compared with experimental results.

  10. Power Plant Power Plant

    E-Print Network [OSTI]

    Stillwater Power Plant Wabuska Power Plant Casa Diablo Power Plant Glass Mountain Geothermal Area Lassen Geothermal Area Coso Hot Springs Power Plants Lake City Geothermal Area Thermo Geothermal Area Lakeview Geothermal Area Raft River Geothermal Area Cove Fort Power Plant Roosevelt Power Plant Borax Lake

  11. 1992 Conversion Resources Supply Document

    SciTech Connect (OSTI)

    Not Available

    1992-03-01

    In recent years conservation of electric power has become an integral part of utility planning. The 1980 Pacific Northwest Electric Power Planning and Conservation Act (Northwest Power Act) requires that the region consider conservation potential in planning acquisitions of resources to meet load growth. The Bonneville Power Administration (BPA) developed its first estimates of conservation potential in 1982. Since that time BPA has updated its conservation supply analyses as a part of its Resource Program and other planning efforts. Major updates were published in 1985 and in January 1990. This 1992 document presents updated supply curves, which are estimates of the savings potential over time (cumulative savings) at different cost levels of energy conservation measures (ECMs). ECMs are devices, pieces of equipment, or actions that increase the efficiency of electricity use and reduce the amount of electricity used by end-use equipment.

  12. LED Street Lighting Conversion Workshop Presentations

    Broader source: Energy.gov [DOE]

    This page provides links to the presentations given at the National League of Cities Mobile Workshop, LED Street Lighting Conversion: Saving Your Community Money, While Improving Public Safety,...

  13. Biochemical Conversion: Using Hydrolysis, Fermentation, and Catalysis...

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

    hydrolyze the cellulose and hemicellulose in biomass to free the sugars for conversion. The program is working to identify the most productive, naturally occurring...

  14. "Fundamental Challenges in Solar Energy Conversion" workshop...

    Office of Science (SC) Website

    "Fundamental Challenges in Solar Energy Conversion" workshop hosted by LMI-EFRC Energy Frontier Research Centers (EFRCs) EFRCs Home Centers Research Science Highlights News &...

  15. "Approaches to Ultrahigh Efficiency Solar Energy Conversion"...

    Office of Science (SC) Website

    "Approaches to Ultrahigh Efficiency Solar Energy Conversion" Webinar Energy Frontier Research Centers (EFRCs) EFRCs Home Centers Research Science Highlights News & Events EFRC News...

  16. Limits in high efficiency quantum frequency conversion

    E-Print Network [OSTI]

    Nicolás Quesada; J. E. Sipe

    2015-08-13

    Frequency conversion is an enabling process in many quantum information protocols. In this letter we study fundamental limits to high efficiency frequency conversion imposed by time ordering corrections. Using the Magnus expansion, we argue that these corrections, which are usually considered detrimental, can be used to increase the efficiency of conversion under certain circumstances. The corrections induce a nonlinear behaviour in the probability of upconversion as a function of the pump intensity, significantly modifying the sinusoidal Rabi oscillations that are otherwise expected. Finally, by using a simple scaling argument, we explain why cascaded frequency conversion devices attenuate time ordering corrections, allowing the construction of near ideal quantum pulse gates.

  17. Molecular catalytic coal liquid conversion. Quarterly report...

    Office of Scientific and Technical Information (OSTI)

    report Citation Details In-Document Search Title: Molecular catalytic coal liquid conversion. Quarterly report You are accessing a document from the Department of Energy's (DOE)...

  18. Molecular catalytic coal liquid conversion. Quarterly status...

    Office of Scientific and Technical Information (OSTI)

    report Citation Details In-Document Search Title: Molecular catalytic coal liquid conversion. Quarterly status report In this Quarter, the research was focused continually on the...

  19. Molecular catalytic coal liquid conversion. Quarterly status...

    Office of Scientific and Technical Information (OSTI)

    July--September 1995 Citation Details In-Document Search Title: Molecular catalytic coal liquid conversion. Quarterly status report, July--September 1995 The research was...

  20. Molecular catalytic coal liquid conversion. Quarterly report...

    Office of Scientific and Technical Information (OSTI)

    October--December 1994 Citation Details In-Document Search Title: Molecular catalytic coal liquid conversion. Quarterly report, October--December 1994 You are accessing a...

  1. Molecular catalytic coal liquid conversion. Quarterly status...

    Office of Scientific and Technical Information (OSTI)

    July--September 1995 Citation Details In-Document Search Title: Molecular catalytic coal liquid conversion. Quarterly status report, July--September 1995 You are accessing...

  2. Molecular catalytic coal liquid conversion. Quarterly report...

    Office of Scientific and Technical Information (OSTI)

    October--December 1994 Citation Details In-Document Search Title: Molecular catalytic coal liquid conversion. Quarterly report, October--December 1994 In this Quarter, the...

  3. Molecular catalytic coal liquid conversion. Quarterly report...

    Office of Scientific and Technical Information (OSTI)

    report Citation Details In-Document Search Title: Molecular catalytic coal liquid conversion. Quarterly report In this Quarter, the research was focused continually on the two...

  4. Molecular catalytic coal liquid conversion. Quarterly status...

    Office of Scientific and Technical Information (OSTI)

    report Citation Details In-Document Search Title: Molecular catalytic coal liquid conversion. Quarterly status report You are accessing a document from the Department of...

  5. Conversion Technologies for Advanced Biofuels ? Carbohydrates...

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

    for host organism in the presentence of limited six carbon sugars Identify cellular transporters and regulators required for maximum sugar to hydrocarbon conversion ...

  6. Conversion and enrichment in the Soviet Union

    SciTech Connect (OSTI)

    1991-04-01

    In the Soviet Union, just as in the West, the civilian nuclear industry emerged from research work undertaken for nuclear weapons development. At first, researchers tried various techniques for physical separation of uranium isotopes: electromagnetic and molecular-kinetic thermo-diffusion methods; gaseous diffusion; and centrifuge methods. All of those methods, which are based primarily on differences in the atomic mass of uranium isotopes, called for extensive research and the development of new, technically unprecedented equipment. Gradually gaseous diffusion and gas centrifuge technology became recognized as most feasible for industrial use, so research on other methods was terminated. Industrial-scale uranium enrichment in the Soviet Union began in 1949 using the gaseous diffusion method; by the early 1960s, centrifuge technology was in use on an industrial scale. All Soviet production of highly-enriched, weapons-grade uranium was halted in 1987. The Soviet Union now has four enrichment plants in operation (at classified locations), solely for civilian nuclear power needs. All four enrichment plants have centrifuge modules, and enrichment provided by gaseous diffusion accounts for less than 5% of their total output. Two of the four enrichment plants also incorporate facilities for conversion to uranium hexafluoride (UF{sub 6}).

  7. CERN-PS Main Power Converter Renovation How to Provide and Control the Large Flow of Energy for a Rapid Cyclic Machine?

    E-Print Network [OSTI]

    Bordry, Frederick; Völker, F V

    2005-01-01

    The PS accelerator (Proton-Synchrotron) at CERN, which is part of the LHC injector chain, is composed of one hundred magnets connected in series. During a typical acceleration cycle (taking 2.4 seconds), the active power at the magnet terminals varies from plus to minus 40 MW. As this large active power variation was not acceptable to the electrical network, a motor-generator set (M-G) was inserted between the grid and the load. The M-G set (of 1968) acts as a fly-wheel with a stored kinetic energy of 233 MJ and the magnets are fed via two 12-pulse thyristor rectifiers. A renovation or replacement of the installation is planned in the near future as part of the consolidation of the LHC injectors to avoid any major breakdown, to improve overall availability and to reduce operation and maintenance costs. This paper presents a first comparison of technical solutions available to build such a power system and the strategy that will be applied for the up-grade of the system.

  8. Polyvinyl Chloride/Silica Nanoporous Composite Separator for All-Vanadium Redox Flow Battery Applications

    SciTech Connect (OSTI)

    Wei, Xiaoliang; Nie, Zimin; Luo, Qingtao; Li, Bin; Sprenkle, Vincent L.; Wang, Wei

    2013-04-22

    Redox flow batteries (RFBs) are capable of reversible conversion between electricity and chemical energy. Potential RFB applications resolve around mitigating the discrepancy between electricity production and consumption to improve the stability and utilization of the power infrastructure and tackling the intermittency of renewables such as photovoltaics or wind turbines to enable their reliable integration [1, 2]. Because the energy is stored in externally contained liquid electrolytes and the energy conversion reactions take place at the electrodes, RFBs hold a unique capability to separate energy and power and thus possess considerable design flexibility to meet either energy management driven or power rating oriented grid applications, which is considered to be a unparalleled advantage over conventional solid-state secondary batteries [3]. Other advantages of RFBs include fast response to load changes, high round-trip efficiency, long calender and cycle lives, safe operations, tolerance to deep discharge, etc. [4]. Among various flow battery chemistries, all-vanadium redox flow battery (VRB) was invented by Maria Skyllas-Kazacos at the University of New South Wales in the 1980s [5, 6] and have attracted substantial attention in both research and industrial communities today [7, 8]. A well-recognized advantage that makes VRB stands out among other redox chemistries is the reduced crossover contamination ascribed to employing four different oxidation states of the same vanadium element as the two redox couples. Recently, great progress has led to remarkably improved energy density of VRB by using sulfuric-chloric mixed acid supporting electrolytes that were stable at 2.5M vanadium and had wider operational temperature window of -5~50oC [9], compared with the traditional sulfuric acid VRB system [10].

  9. CONVERSION EXTRACTION DESULFURIZATION (CED) PHASE III

    SciTech Connect (OSTI)

    James Boltz

    2005-03-01

    This project was undertaken to refine the Conversion Extraction Desulfurization (CED) technology to efficiently and economically remove sulfur from diesel fuel to levels below 15-ppm. CED is considered a generic term covering all desulfurization processes that involve oxidation and extraction. The CED process first extracts a fraction of the sulfur from the diesel, then selectively oxidizes the remaining sulfur compounds, and finally extracts these oxidized materials. The Department of Energy (DOE) awarded Petro Star Inc. a contract to fund Phase III of the CED process development. Phase III consisted of testing a continuous-flow process, optimization of the process steps, design of a pilot plant, and completion of a market study for licensing the process. Petro Star and the Degussa Corporation in coordination with Koch Modular Process Systems (KMPS) tested six key process steps in a 7.6-centimeter (cm) (3.0-inch) inside diameter (ID) column at gas oil feed rates of 7.8 to 93.3 liters per hour (l/h) (2.1 to 24.6 gallons per hour). The team verified the technical feasibility with respect to hydraulics for each unit operation tested and successfully demonstrated pre-extraction and solvent recovery distillation. Test operations conducted at KMPS demonstrated that the oxidation reaction converted a maximum of 97% of the thiophenes. The CED Process Development Team demonstrated that CED technology is capable of reducing the sulfur content of light atmospheric gas oil from 5,000-ppm to less than 15-ppm within the laboratory scale. In continuous flow trials, the CED process consistently produced fuel with approximately 20-ppm of sulfur. The process economics study calculated an estimated process cost of $5.70 per product barrel. The Kline Company performed a marketing study to evaluate the possibility of licensing the CED technology. Kline concluded that only 13 refineries harbored opportunity for the CED process. The Kline study and the research team's discussions with prospective refineries led to the conclusion that there were not likely prospects for the licensing of the CED process.

  10. Framing the Conversation: The Role of Facebook Conversations in Shopping for Eyeglasses

    E-Print Network [OSTI]

    Kane, Shaun K.

    Framing the Conversation: The Role of Facebook Conversations in Shopping for Eyeglasses Karim Said Warby Parker's Facebook page and explore the ways customers formulate questions and conversations,000 Facebook posts, consisting of photos, comments, and "likes". Using statistical analyses and qualitative

  11. Derivation of Locational Marginal Prices for Restructured Wholesale Power Markets

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    the performance of these markets. In this paper, different AC and DC optimal power flow (OPF) models are presented Operator (MISO). Keywords: Locational marginal pricing, wholesale power market, AC optimal power flow, DC optimal power flow, U.S. Midwest Independent System Operator (MISO). #12;3 1 INTRODUCTION In an April 2003

  12. Thermoelectric power generator for variable thermal power source

    DOE Patents [OSTI]

    Bell, Lon E; Crane, Douglas Todd

    2015-04-14

    Traditional power generation systems using thermoelectric power generators are designed to operate most efficiently for a single operating condition. The present invention provides a power generation system in which the characteristics of the thermoelectrics, the flow of the thermal power, and the operational characteristics of the power generator are monitored and controlled such that higher operation efficiencies and/or higher output powers can be maintained with variably thermal power input. Such a system is particularly beneficial in variable thermal power source systems, such as recovering power from the waste heat generated in the exhaust of combustion engines.

  13. Biomass thermal conversion research at SERI

    SciTech Connect (OSTI)

    Milne, T. A.; Desrosiers, R. E.; Reed, T. B.

    1980-09-01

    SERI's involvement in the thermochemical conversion of biomass to fuels and chemicals is reviewed. The scope and activities of the Biomass Thermal Conversion and Exploratory Branch are reviewed. The current status and future plans for three tasks are presented: (1) Pyrolysis Mechanisms; (2) High Pressure O/sub 2/ Gasifier; and (3) Gasification Test Facility.

  14. Heat to electricity thermoacoustic-magnetohydrodynamic conversion

    E-Print Network [OSTI]

    Castrejon-Pita, A A

    2006-01-01

    In this work, a new concept for the conversion of heat into electricity is presented. The conversion is based on the combined effects of a thermoacoustic prime mover coupled with a magnetohydrodynamic generator, using different working fluids in each process. The results of preliminary experiments are also presented.

  15. Heat to electricity thermoacoustic-magnetohydrodynamic conversion

    E-Print Network [OSTI]

    A. A. Castrejon-Pita; G. Huelsz

    2006-10-12

    In this work, a new concept for the conversion of heat into electricity is presented. The conversion is based on the combined effects of a thermoacoustic prime mover coupled with a magnetohydrodynamic generator, using different working fluids in each process. The results of preliminary experiments are also presented.

  16. Unit Conversion Factors Quantity Equivalent Values

    E-Print Network [OSTI]

    Ashurst, W. Robert

    Unit Conversion Factors Quantity Equivalent Values Mass 1 kg = 1000 g = 0.001 metric ton = 2·R 10.73 psia·ft3 lbmol·R 62.36 liter·torr mol·K 0.7302 ft3·atm lbmol·R Temperature Conversions: T

  17. The high conversion LC-Fining process

    SciTech Connect (OSTI)

    VanDriesen, R.P.; Strangio, V.A.; Rhoe, A.; Kolstad, J.J.

    1986-01-01

    Residual oil hydrocracking has been practiced at moderate conversions for many years on a wide range of feedstocks. Processes utilizing expanded bed reactors have been proven to be effective in the hydrocracking of these heavy residual feedstocks. Conversions up to 60% vacuum bottoms to distillates were routinely obtained in several commercial units. More recently Amoco has been operating an LC-Fining unit in their Texas City refinery at conversions as high as 80%. Normal conversion in this plant however is 60-65%. LC-Fining is an expanded bed resid hydrocracking and hydrodesulfurization process developed by Cities Service and Lummus Crest. There are a number of factors which may limit the conversion in any given plant site. These include compatibility problems with the liquid product, settling out of heavy hydrocarbons in downstream equipment or fouling of the catalyst in the reactor which in the extreme results in coking of the catalyst bed. The operator of a residual hydrocracker maintains conversion at a sufficiently low level to avoid these problems. Recent advances in the LC-Fining technology have led to the development of the High Conversion LC-Fining Process which is capable of operation at conversions of 95% and higher without any of these problems.

  18. Data Conversion in Residue Number System

    E-Print Network [OSTI]

    Zilic, Zeljko

    ;2 Abstract This thesis tackles the problem of data conversion in the Residue Number System (RNS). The RNS has the use of RNS at the applications. In this thesis, we aim at developing efficient schemes for the conversion from the conventional representation to the RNS representation and vice versa. The conventional

  19. LINEAR TRANSIENT FLOW SOLUTION FOR PRIMARY OIL RECOVERY

    E-Print Network [OSTI]

    Patzek, Tadeusz W.

    in a low-permeability, compressible, layered reservoir filled with oil, water and gas. The sample for pressure support and incremental oil recovery. We analyze the pressure response and fluid flow ratesLINEAR TRANSIENT FLOW SOLUTION FOR PRIMARY OIL RECOVERY WITH INFILL AND CONVERSION TO WATER

  20. New process speeds conversion of biomass to fuels

    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 shinesSolarNew scholarship supportsFeet) UndergroundArgonneConversion of

  1. Synoptic and local influences on boundary layer processes, with an application to California wind power

    E-Print Network [OSTI]

    Mansbach, David K

    2010-01-01

    maps showing locations of wind power conversion facilities,of US winds and wind power at 80 m derived fromEvaluation of global wind power. Journal of Geo- physical

  2. New AC-DC Power Factor Correction Architecture Suitable for High Frequency Operation

    E-Print Network [OSTI]

    Lim, Seungbum

    This paper presents a novel ac-dc power factor correction (PFC) power conversion architecture for single-phase grid interface. The proposed architecture has significant advantages for achieving high efficiency, good power ...

  3. Sibley station low-sulfur coal conversion program

    SciTech Connect (OSTI)

    Rupinskas, R.L. [Sargent & Lundy LLC, Chicago, IL (United States); Rembold, D.F. [Missouri Public Service, Kansas City, MO (United States)

    1995-03-01

    After embarking on an upgrade project in 1986 that was designed to allow efficient and reliable operation of its coal-fired Sibley station through 2010, Missouri Public Service (MPS) faced the uncertainty of impending acid-rain legislation. To protect its investment in the Sibley Rebuild Program, the utility evaluated compliance options based on the emerging legislation and concluded that switching to low-sulfur coal offered the least-cost compliance approach. Compared to installing a scrubber, switching to a low-sulfur coal was also more straightforward, although not without challenges and complications. This paper reviews the Sibley low-sulfur coal conversion program. At Sibley, fuel switching was chosen only after numerous internal and external studies; it withstood late challenges from natural gas and allowance trading. Switching demanded additional equipment to blend Power River Basin coals and other coals, and demanded additional and upgraded protective equipment in the areas of fire protection, dust collection, and explosion prevention. In the year since the coal conversion project was completed the facility has operated reliably, the economic benefits of the lower cost Powder River Basin coals have been realized, and the station has also met the requirements of both phases of the acid rain legislation. Fuel switching at Sibley required a team approach and careful analysis. The coal conversion project also required attention and dedication by team members in order to minimize fuel costs while maintaining optimum plant efficiency and availability.

  4. The gradient flow in simple field theories

    E-Print Network [OSTI]

    Monahan, Christopher

    2015-01-01

    The gradient flow is a valuable tool for the lattice community, with applications from scale-setting to implementing chiral fermions. Here I focus on the gradient flow as a means to suppress power-divergent mixing. Power-divergent mixing stems from the hypercubic symmetry of the lattice regulator and is a particular difficulty for calculations of, for example, high moments of parton distribution functions. The gradient flow removes power-divergent mixing on the lattice, provided the flow time is kept fixed in physical units, at the expense of introducing a new physical scale in the continuum. One approach to dealing with this new scale is the smeared operator product expansion, a formalism that systematically connects nonperturbative calculations of flowed operators to continuum physics. I study the role of the gradient flow in suppressing power-divergent mixing and present the first nonperturbative study in scalar field theory.

  5. The gradient flow in simple field theories

    E-Print Network [OSTI]

    Christopher Monahan

    2015-12-01

    The gradient flow is a valuable tool for the lattice community, with applications from scale-setting to implementing chiral fermions. Here I focus on the gradient flow as a means to suppress power-divergent mixing. Power-divergent mixing stems from the hypercubic symmetry of the lattice regulator and is a particular difficulty for calculations of, for example, high moments of parton distribution functions. The gradient flow removes power-divergent mixing on the lattice, provided the flow time is kept fixed in physical units, at the expense of introducing a new physical scale in the continuum. One approach to dealing with this new scale is the smeared operator product expansion, a formalism that systematically connects nonperturbative calculations of flowed operators to continuum physics. I study the role of the gradient flow in suppressing power-divergent mixing and present the first nonperturbative study in scalar field theory.

  6. Flow chamber

    DOE Patents [OSTI]

    Morozov, Victor (Manassas, VA)

    2011-01-18

    A flow chamber having a vacuum chamber and a specimen chamber. The specimen chamber may have an opening through which a fluid may be introduced and an opening through which the fluid may exit. The vacuum chamber may have an opening through which contents of the vacuum chamber may be evacuated. A portion of the flow chamber may be flexible, and a vacuum may be used to hold the components of the flow chamber together.

  7. Chemical preconcentrator with integral thermal flow sensor

    DOE Patents [OSTI]

    Manginell, Ronald P. (Albuquerque, NM); Frye-Mason, Gregory C. (Cedar Crest, NM)

    2003-01-01

    A chemical preconcentrator with integral thermal flow sensor can be used to accurately measure fluid flow rate in a microanalytical system. The thermal flow sensor can be operated in either constant temperature or constant power mode and variants thereof. The chemical preconcentrator with integral thermal flow sensor can be fabricated with the same MEMS technology as the rest of the microanlaytical system. Because of its low heat capacity, low-loss, and small size, the chemical preconcentrator with integral thermal flow sensor is fast and efficient enough to be used in battery-powered, portable microanalytical systems.

  8. Geological flows

    E-Print Network [OSTI]

    Yu. N. Bratkov

    2008-11-19

    In this paper geology and planetology are considered using new conceptual basis of high-speed flow dynamics. Recent photo technics allow to see all details of a flow, 'cause the flow is static during very short time interval. On the other hand, maps and images of many planets are accessible. Identity of geological flows and high-speed gas dynamics is demonstrated. There is another time scale, and no more. All results, as far as the concept, are new and belong to the author. No formulae, pictures only.

  9. Flow regimes

    SciTech Connect (OSTI)

    Liles, D.R.

    1982-01-01

    Internal boundaries in multiphase flow greatly complicate fluid-dynamic and heat-transfer descriptions. Different flow regimes or topological configurations can have radically dissimilar interfacial and wall mass, momentum, and energy exchanges. To model the flow dynamics properly requires estimates of these rates. In this paper the common flow regimes for gas-liquid systems are defined and the techniques used to estimate the extent of a particular regime are described. Also, the current computer-code procedures are delineated and introduce a potentially better method is introduced.

  10. Photoferroelectric solar to electrical conversion

    E-Print Network [OSTI]

    Milos Knezevic; Mark Warner

    2013-01-30

    We propose a charge pump which converts solar energy into DC electricity. It is based on cyclic changes in the spontaneous electric polarization of a photoferroelectric material, which allows a transfer of charge from a low to a high voltage. To estimate the power efficiency we use a photoferroelectric liquid crystal as the working substance. For a specific choice of material, an efficiency of $2\\%$ is obtained.

  11. Energy conversion & storage program. 1994 annual report

    SciTech Connect (OSTI)

    Cairns, E.J.

    1995-04-01

    The Energy Conversion and Storage Program investigates state-of-the-art electrochemistry, chemistry, and materials science technologies for: (1) development of high-performance rechargeable batteries and fuel cells; (2) development of high-efficiency thermochemical processes for energy conversion; (3) characterization of complex chemical processes and chemical species; (4) study and application of novel materials for energy conversion and transmission. Research projects focus on transport process principles, chemical kinetics, thermodynamics, separation processes, organic and physical chemistry, novel materials, and advanced methods of analysis.

  12. Energy Conversion & Storage Program, 1993 annual report

    SciTech Connect (OSTI)

    Cairns, E.J.

    1994-06-01

    The Energy Conversion and Storage Program applies chemistry and materials science principles to solve problems in: production of new synthetic fuels; development of high-performance rechargeable batteries and fuel cells; development of high-efficiency thermochemical processes for energy conversion; characterization of complex chemical processes and chemical species; and the study and application of novel materials for energy conversion and transmission. Projects focus on transport-process principles, chemical kinetics, thermodynamics, chemical kinetics, thermodynamics, separation processes, organic and physical chemistry, novel materials, and advanced methods of analysis.

  13. Ocean Thermal Energy Conversion Basics | Department of Energy

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

    Ocean Thermal Energy Conversion Basics Ocean Thermal Energy Conversion Basics August 16, 2013 - 4:22pm Addthis A process called ocean thermal energy conversion (OTEC) uses the heat...

  14. Renaissance in Flow-Cell Technologies Recent Advancements and Future Opportunities

    E-Print Network [OSTI]

    Electrodes Thick = High Energy Thin = High Power 4 #12;uper or s y UTC Proprietary Flow Batteries cells Flow Battery SystemFlow Battery System Electrolyte flow Ion exchange membrane Cell stack (power System Architectures Proton Exchange Membrane Flow Batteries: Energy stored in solutions

  15. Power Quality/Harmonic Detection: Harmonic Control in Electric Power Systems for the Telecommunications Industry 

    E-Print Network [OSTI]

    Felkner, L. J.; Waggoner, R. M.

    1993-01-01

    The control of harmonics in power systems continues to be a major concern in the telecommunications industry. AC/DC telecommunication conversion equipment has rarely been thought of as playing a major role in the harmonic interaction problem. Yet...

  16. OCEAN THERMAL ENERGY CONVERSION: AN OVERALL ENVIRONMENTAL ASSESSMENT

    SciTech Connect (OSTI)

    Sands, M.Dale

    1980-08-01

    Significant acccrmplishments in Ocean Thermal Energy Conversion (OTEC) technology have increased the probability of producing OTEC-derived power within this decade with subsequent large scale commercialization following by the turn of the century. Under U.S. Department of Energy funding, the Oceanic Engineering Operations of Interstate Electronics Corporation has prepared several OTEC Environmental Assessments over the past years, in particular, the OTEC Programmatic Environmental Assessment. The Programmatic EA considers several technological designs (open- and closed-cycle), plant configuratlons (land-based, moored, and plant-ship), and power usages (baseload electricity, ammonia and aluminum production). Potential environmental impacts, health and safetv issues and a status update of the institutional issues as they influence OTEC deployments, are included.

  17. Membrane-less hydrogen bromine flow battery

    E-Print Network [OSTI]

    Braff, W A; Buie, C R

    2014-01-01

    In order for the widely discussed benefits of flow batteries for electrochemical energy storage to be applied at large scale, the cost of the electrochemical stack must come down substantially. One promising avenue for reducing stack cost is to increase the system power density while maintaining efficiency, enabling smaller stacks. Here we report on a membrane-less, hydrogen bromine laminar flow battery as a potential high power density solution. The membrane-less design enables power densities of 0.795 W cm$^{-2}$ at room temperature and atmospheric pressure, with a round-trip voltage efficiency of 92\\% at 25\\% of peak power. Theoretical solutions are also presented to guide the design of future laminar flow batteries. The high power density achieved by the hydrogen bromine laminar flow battery, along with the potential for rechargeable operation, will translate into smaller, inexpensive systems that could revolutionize the fields of large-scale energy storage and portable power systems.

  18. Summer Series 2012 - Conversation with Omar Yaghi

    ScienceCinema (OSTI)

    Omar Yaghi

    2013-06-24

    Jeff Miller, head of Public Affairs, sat down in conversation with Omar Yaghi, director of the Molecular Foundry, in the first of a series of "powerpoint-free" talks on July 11th 2012, at Berkeley Lab.

  19. Summer Series 2012 - Conversation with Kathy Yelick

    SciTech Connect (OSTI)

    Kathy Yelick

    2012-07-23

    Jeff Miller, head of Public Affairs, sat down in conversation with Kathy Yelick, Associate Berkeley Lab Director, Computing Sciences, in the second of a series of "powerpoint-free" talks on July 18th 2012, at Berkeley Lab.

  20. The Conversion of Waste to Energy 

    E-Print Network [OSTI]

    John, T.; Cheek, L.

    1980-01-01

    Almost every industrial operation produces some combustible waste, but conversion of this to useful energy is often more difficult than with other energy recovery projects and requires careful attention to design, operating and maintaining...

  1. Assessment of ocean thermal energy conversion

    E-Print Network [OSTI]

    Muralidharan, Shylesh

    2012-01-01

    Ocean thermal energy conversion (OTEC) is a promising renewable energy technology to generate electricity and has other applications such as production of freshwater, seawater air-conditioning, marine culture and chilled-soil ...

  2. Summer Series 2012 - Conversation with Kathy Yelick

    ScienceCinema (OSTI)

    Yelick, Kathy

    2013-06-24

    Jeff Miller, head of Public Affairs, sat down in conversation with Kathy Yelick, Associate Berkeley Lab Director, Computing Sciences, in the second of a series of "powerpoint-free" talks on July 18th 2012, at Berkeley Lab.

  3. Collaboration on Topic Change in Conversation

    E-Print Network [OSTI]

    Howe, Mary

    1991-01-01

    Conversations are cooperatively achieved speech events. Analysis of topic changes shows that topic endings are negotiated by participants over a series of turns, using the following specific types of indicators: summary assessments, acknowledgment...

  4. Solar thermophotovoltaic energy conversion systems with two-dimensional tantalum photonic crystal absorbers and emitters

    E-Print Network [OSTI]

    Soljačić, Marin

    Solar thermophotovoltaic energy conversion systems with two-dimensional tantalum photonic crystal) systems convert solar energy into electricity via thermally radiated photons at tailored wavelengths highly scalable for a wide range of power capacities, have no moving parts, and allow solar energy

  5. Algae-to-Fuel: Integrating Thermochemical Conversion, Nutrient...

    Office of Environmental Management (EM)

    Algae-to-Fuel: Integrating Thermochemical Conversion, Nutrient Recycling, and Wastewater Algae-to-Fuel: Integrating Thermochemical Conversion, Nutrient Recycling, and Wastewater...

  6. Conversion Technologies for Advanced Biofuels - Bio-Oil Production...

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

    Oil Production Conversion Technologies for Advanced Biofuels - Bio-Oil Production RTI International report-out at the CTAB webinar on Conversion Technologies for Advanced Biofuels...

  7. Conversion Technologies for Advanced Biofuels - Bio-Oil Upgrading...

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

    ebinarbiooilsupgrading.pdf More Documents & Publications Conversion Technologies for Advanced Biofuels - Bio-Oil Production Thermochemical Conversion Proceeses to Aviation Fuels...

  8. First-of-its-Kind Carbon Capture and Conversion Demonstration...

    Office of Environmental Management (EM)

    First-of-its-Kind Carbon Capture and Conversion Demonstration Technology Opening in Texas First-of-its-Kind Carbon Capture and Conversion Demonstration Technology Opening in Texas...

  9. OCEAN THERMAL ENERGY CONVERSION (OTEC) PROGRAMMATIC ENVIRONMENTAL ANALYSIS

    E-Print Network [OSTI]

    Sands, M. D.

    2011-01-01

    310, the Ocean the Ocean Energy Thermal Energy Conversionfor the commercialization of ocean thermal energy conversionOpen cycle ocean thermal energy conversion. A preliminary

  10. Recycling of wasted energy : thermal to electrical energy conversion

    E-Print Network [OSTI]

    Lim, Hyuck

    2011-01-01

    making direct thermal energy storage methods, e.g. thosethermal shorting, that limits the energy conversion efficiency of direct thermoelectric energy conversion methods.

  11. 2015 Peer Review Presentations-Thermochemical Conversion | Department...

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

    Thermochemical Conversion 2015 Peer Review Presentations-Thermochemical Conversion The Bioenergy Technologies Office hosted its 2015 Project Peer Review on March 23-27, 2015, at...

  12. 2015 Peer Review Presentations-Biochemical Conversion | Department...

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

    Biochemical Conversion 2015 Peer Review Presentations-Biochemical Conversion The Bioenergy Technologies Office hosted its 2015 Project Peer Review on March 23-27, 2015, at the...

  13. Novel Transparent Phosphor Conversion Matrix with High Thermal...

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

    Transparent Phosphor Conversion Matrix with High Thermal Conductivity for Next-Generation Phosphor-Converted LED-based Solid State Lighting Novel Transparent Phosphor Conversion...

  14. Molecular catalytic coal liquid conversion (Conference) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Conference: Molecular catalytic coal liquid conversion Citation Details In-Document Search Title: Molecular catalytic coal liquid conversion This research, which is relevant to the...

  15. Molecular catalytic coal liquid conversion (Conference) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Conference: Molecular catalytic coal liquid conversion Citation Details In-Document Search Title: Molecular catalytic coal liquid conversion You are accessing a document from...

  16. Composites for Multi-energy conversion & waste heat recovery...

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

    Composites for Multi-energy conversion & waste heat recovery Composites for Multi-energy conversion & waste heat recovery Discusses development of a composite that transfers energy...

  17. Process Design and Economics for the Conversion of Lignocellulosic...

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

    of Biomass to Sugars and Biological Conversion of Sugars to Hydrocarbons Process Design and Economics for the Conversion of Lignocellulosic Biomass to Hydrocarbons:...

  18. Novel Vertimass Catalyst for Conversion of Ethanol and Other...

    Office of Environmental Management (EM)

    Novel Vertimass Catalyst for Conversion of Ethanol and Other Alcohols into Fungible Gasoline, Jet, and Diesel Fuel Blend Stocks Novel Vertimass Catalyst for Conversion of Ethanol...

  19. Nanostructured High-Temperature Bulk Thermoelectric Energy Conversion...

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

    High-Temperature Bulk Thermoelectric Energy Conversion for Efficient Automotive Waste Heat Recovery Nanostructured High-Temperature Bulk Thermoelectric Energy Conversion for...

  20. New process speeds conversion of biomass to fuels

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

    Conversion of Biomass to Fuels New process speeds conversion of biomass to fuels Scientists made a major step forward recently towards transforming biomass-derived molecules into...