National Library of Energy BETA

Sample records for roof ice melt

  1. Water freezing and ice melting

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

    Malolepsza, Edyta; Keyes, Tom

    2015-10-12

    The generalized replica exchange method (gREM) is designed to sample states with coexisting phases and thereby to describe strong first order phase transitions. The isobaric MD version of the gREM is presented and applied to freezing of liquid water, and melting of hexagonal and cubic ice. It is confirmed that coexisting states are well sampled. The statistical temperature as a function of enthalpy, TS(H), is obtained. Hysteresis between freezing and melting is observed and discussed. The entropic analysis of phase transitions is applied and equilibrium transition temperatures, latent heats, and surface tensions are obtained for hexagonal ice↔liquid and cubic ice↔liquid,more » with excellent agreement with published values. A new method is given to assign water molecules among various symmetry types. As a result, pathways for water freezing, ultimately leading to hexagonal ice, are found to contain intermediate layered structures built from hexagonal and cubic ice.« less

  2. ARM - Lesson Plans: When Land Ice Melts

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

    The Arctic and Antarctica are covered with large, heavy sheets of ice. Other islands like New Zealand have ice masses in the form of glaciers on them. When land-based ice melts, ...

  3. Complex systems influence melting of Greenland ice sheet

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

    melting of Greenland ice sheet Complex systems influence melting of Greenland ice sheet International research team's field work shows that, well, things are more complicated...

  4. ARM - What About Melting Polar Ice Caps and Sea Levels?

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

    What About Melting Polar Ice Caps and Sea Levels? Outreach Home Room News Publications Traditional Knowledge Kiosks Barrow, Alaska Tropical Western Pacific Site Tours Contacts Students Study Hall About ARM Global Warming FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox Lesson Plans What About Melting Polar Ice Caps and Sea Levels? As the northern polar zone warms up, sea ice could melt (very probable) and the sea/ice interface could retreat to the north. This is likely to

  5. Melting of ice wedges adds to arctic warming

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

    Can we someday predict earthquakes? Melting of ice wedges adds to arctic warming New ways of looking at seismic information and innovative laboratory experiments are offering tantalizing clues to what triggers earthquakes-and when. March 14, 2016 Ice throughout the Arctic is vanishing due to a rapidly warming climate. Ice throughout the Arctic is vanishing due to a rapidly warming climate. Melting of ice wedges adds to arctic warming Ice wedges are a particularly cool surface feature in the

  6. Melting of Ice Under Pressure | Argonne Leadership Computing Facility

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

    Melting of Ice Under Pressure Authors: Schwegler, E., Sharma, M., Gygi, F., Galli, G. The melting of ice under pressure is investigated with a series of first-principles molecular dynamics simulations. In particular, a two-phase approach is used to determine the melting temperature of the ice-VII phase in the range of 10 Publication Date: August, 2008 Name of Publication Source: The National Academy of Sciences Proceedings Publisher: The National Academy of Sciences of the USA Volume: 0 Issue: 0

  7. Melting of ice wedges adds to arctic warming

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

    Ice wedges are a particularly cool surface feature in the Arctic tundra. And new research suggests they are melting fast, which is bad news for the ecosystem at the top of the ...

  8. Complex systems influence melting of Greenland ice sheet

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

    Complex systems influence melting of Greenland ice sheet Complex systems influence melting of Greenland ice sheet International research team's field work shows that, well, things are more complicated than we thought December 22, 2014 The newly discovered rolling movement shown in (A) three-dimensional cryo-electron microscopy image of ribosome, and (B) computer-generated atomic-resolution model of the human ribosome consistent with microscopy. An international team of researchers deployed to

  9. New climate model predicts likelihood of Greenland ice melt, sea level rise

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

    and dangerous temperatures New climate model predicts likelihood of Greenland ice melt New climate model predicts likelihood of Greenland ice melt, sea level rise and dangerous temperatures A new computer model of accumulated carbon emissions predicts the likelihood of crossing several dangerous climate change thresholds. November 20, 2015 Greenland ice loss. Greenland ice loss. Contact Kevin Roark Communications Office (505) 665-9202 Email "The model is based on idealized

  10. Cool Roofs

    Energy Savers [EERE]

    ... Selecting cool roof type that retains better surface properties can give better lifetime energy savings for the cool roof. For the metal roof, these metal roofs have better ...

  11. Roof Renovations

    Broader source: Energy.gov [DOE]

    The roof of a Federal building is a common placement for a number of renewable energy technologies, so they should be addressed anytime a roof renovation is undertaken, including roof-mounted...

  12. White Roofs

    ScienceCinema (OSTI)

    Chu, Steven

    2013-05-29

    Secretary Steven Chu discusses the benefits of switching to white roofs and light colored pavements.

  13. Green Roofs

    SciTech Connect (OSTI)

    2004-08-01

    A New Technology Demonstration Publication Green roofs can improve the energy performance of federal buildings, help manage stormwater, reduce airborne emissions, and mitigate the effects of urban heat islands.

  14. Promising Technology: Cool Roofs

    Broader source: Energy.gov [DOE]

    A cool roof increases the solar reflectance of the roof surface. By reflecting more sunlight, the roof surface maintains a cooler temperature. This decrease in temperature leads to less heat transfer through the roof into the building below. During the cooling season, the addition of a cool roof can decrease the cooling load of the building.

  15. One Cool Roof

    Broader source: Energy.gov [DOE]

    The 134,629 sq. ft. (about 3 acres) roof of the Office of Scientific and Technical Information (OSTI) building in Oak Ridge, Tennessee is now officially a "Cool Roof" -- making it energy efficient in ways that darker roofs are not. Cool roofs are light in color, and therefore, reflect rather than absorb sunlight.

  16. Roof bolting improvements

    SciTech Connect (OSTI)

    Fiscor, S.

    2008-11-15

    Suppliers partner with mine operators to offer safer, more productive tools for roof bolting. 4 figs.

  17. New "Cool Roof Time Machine" Will Accelerate Cool Roof Deployment...

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

    "Cool Roof Time Machine" Will Accelerate Cool Roof Deployment New "Cool Roof Time Machine" Will Accelerate Cool Roof Deployment April 24, 2015 - 4:21pm Addthis Berkeley Lab...

  18. Guide to Cool Roofs

    Energy Savers [EERE]

    beautify your home. The immediate and long-term benefits of roofs that stay cool in the sun have made cool roofing the fastest growing sector of the building industry. Studies...

  19. Roof Savings Calculator Suite

    SciTech Connect (OSTI)

    New, Joshua R; Garrett, Aaron; Erdem, Ender; Huang, Yu

    2013-11-22

    The software options currently supported by the simulation engine can be seen/experienced at www.roofcalc.com. It defaults all values to national averages with options to test a base-case (residential or commercial) building versus a comparison building with inputs for building type, location, building vintage, conditioned area, number of floors, and window-to-wall ratio, cooling system efficiency, type of heating, heating system efficiency, duct location, roof/ceiling insulation level, above-sheathing ventilation, radiant barrier, roof thermal mass, roof solar reflectance, roof thermal emittance, utility costs, roof pitch. The Roof Savings Caculator Suite adds utilities and website/web service and the integration of AtticSim with DOE-2.1E, with the end-result being Roof Savings Calculator.

  20. Solar collector roof

    SciTech Connect (OSTI)

    Marossy, G.; Mueller, W.E.

    1983-07-19

    A solar roof is disclosed for providing air heated by solar energy to the interior of a prefabricated building of the type having a relatively low pitched roof structure formed by a plurality of interlocking ribbed roof panels. A solar radiation transmissive glazing is attached between the roof panel ribs or other support members to form air passageways. A duct-like inlet plenum communicates with the inlet of each passageway for selectively directing air from inside or outside of the building passageways. A duct-like exhaust plenum communicates with the outlet of each passageway for directing heated air to the building interior. The roof surface may be provided with a darkened coating to increase the absorptivity of the surface and increase the collecting efficiency. The glazing material may be thin flexible solar radiation transmissive sheets or relatively rigid panels of solar radiation transmissive material. The solar roof may be retrofitted to an existing roof structure to provide supplemental solar heating capability.

  1. Roof Savings Calculator Suite

    Energy Science and Technology Software Center (OSTI)

    2013-11-22

    The software options currently supported by the simulation engine can be seen/experienced at www.roofcalc.com. It defaults all values to national averages with options to test a base-case (residential or commercial) building versus a comparison building with inputs for building type, location, building vintage, conditioned area, number of floors, and window-to-wall ratio, cooling system efficiency, type of heating, heating system efficiency, duct location, roof/ceiling insulation level, above-sheathing ventilation, radiant barrier, roof thermal mass, roof solar reflectance,more » roof thermal emittance, utility costs, roof pitch. The Roof Savings Caculator Suite adds utilities and website/web service and the integration of AtticSim with DOE-2.1E, with the end-result being Roof Savings Calculator.« less

  2. Mine roof support

    SciTech Connect (OSTI)

    Bollmann, A.

    1981-02-24

    A mine roof support has a base and a roof shield pivoted to the base and carrying at its upper end a pivoted cap which is urged upwardly against the mine roof by a hydraulic pit prop reacting between the cap and the base. The lower end of the roof shield is connected to the base by two links each having a pivot cooperating with a pivot on the roof shield, and a pivot cooperating with a pivot on the base. In addition, the base and/or the lower end of the roof shield has an auxiliary for each link and each link has an auxiliary pivot which can be connected with one of the auxiliary pivots of the base or lower end.

  3. Energy 101: Cool Roofs

    ScienceCinema (OSTI)

    None

    2013-05-29

    This edition of Energy 101 takes a look at how switching to a cool roof can save you money and benefit the environment.

  4. Cool Roofs: An Introduction

    Broader source: Energy.gov [DOE]

    I've been hearing a lot about cool roof technologies, so I welcomed the chance to learn more at a recent seminar.

  5. Cool Roofing Technologies

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

    Cool Roofing Technologies Hashem Akbari Heat Island Group Ernest Orlando Lawrence Berkeley National Laboratory Tel: 510-486-4287 E_mail: H_Akbari@LBL.gov http://HeatIsland.LBL.gov STEAB Visit to LBNL August 14, 2007 2 Orthophoto of Sacramento 3 Under the Canopy Fabric of Sacramento, CA 0 10 20 30 40 50 60 70 80 Downtown Industrial Industrial Office Com. Com. Res. % of surface area Grass Roofs Pavements Others Cooling roofs by increasing solar reflectance * A conventional dark roof absorbs most

  6. Energy 101: Cool Roofs

    K-12 Energy Lesson Plans and Activities Web site (EERE)

    This edition of Energy 101 takes a look at how switching to a cool roof can save you money and benefit the environment.

  7. Guide to Cool Roofs

    SciTech Connect (OSTI)

    2011-02-01

    Traditional dark-colored roofing materials absorb sunlight, making them warm in the sun and increasing the need for air conditioning. White or special "cool color" roofs absorb less sunlight, stay cooler in the sun and transmit less heat into the building.

  8. Why Cool Roofs?

    ScienceCinema (OSTI)

    Chu, Steven

    2013-05-29

    By installing a cool roof at DOE, the federal government and Secretary Chu are helping to educate families and businesses about the important energy and cost savings that can come with this simple, low-cost technology. Cool roofs have the potential to quickly and dramatically reduce global carbon emissions while saving money every month on consumers' electrical bills.

  9. Roof bolting equipment & technology

    SciTech Connect (OSTI)

    Fiscor, S.

    2009-04-15

    Technology provides an evaluator path to improvement for roof bolting machines. Bucyrus offers three different roof bolts models for various mining conditions. The LRB-15 AR is a single-arm boiler recommended for ranges of 32 inches and above; the dual-arm RB2-52A for ranges of 42 inches and above; and the dual-arm RB2-88A for ranges of 54 inches and above. Design features are discussed in the article. Developments in roof bolting technology by Joy Mining Machinery are reported. 4 photos.

  10. Mine roof support system

    SciTech Connect (OSTI)

    Culley, D.H.

    1982-01-26

    A mine roof support system is disclosed having sets of laterally spaced pairs of elongated support members adapted to be moved into and out of abutting relation with a mine roof. Wheel supported frames extend between and connect adjacent end portions of each pair of support members with adjacent wheel supported frames at the ends of the support members being in spaced tandem relation and connected to each other by connector members. Extensible prop members are connected to and move the wheel supported frames and the elongated support members connected thereto selectively toward and away from the mine roof.

  11. Cool Roofs | Department of Energy

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

    Design » Design for Efficiency » Cool Roofs Cool Roofs Learn how switching to a cool roof can save you money and benefit the environment. A cool roof is one that has been designed to reflect more sunlight and absorb less heat than a standard roof. Cool roofs can be made of a highly reflective type of paint, a sheet covering, or highly reflective tiles or shingles. Nearly any type of building can benefit from a cool roof, but consider the climate and other factors before deciding to install

  12. Why Cool Roofs?

    Broader source: Energy.gov [DOE]

    By installing a cool roof at DOE, the federal government and Secretary Chu are helping to educate families and businesses about the important energy and cost savings that can come with this simple,...

  13. Mine roof support

    SciTech Connect (OSTI)

    Bollmann, A.

    1982-01-05

    A mine roof support has a base, a supporting prop extending upwardly from the base, an elongated roof-supporting element having one portion supported by the supporting prop and another portion telescopable relative to the one portion toward a mine face and having a free end formed as a housing with a width corresponding to the width of the one portion, and a thrust prop arranged to support the free end section of the telescopable portion of the roof-supporting element and having a roof-side end section which is forcedly displaceable in the housing in direction of elongation of a mine and pivotable in a substantially vertical plane about an axle arranged in the housing.

  14. Cool Roofs | Department of Energy

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

    ... Spray polyurethane foam roofs are constructed by mixing two liquid chemicals together that react and expand to form one solid piece that adheres to the roof. Foams are highly ...

  15. Ice electrode electrolytic cell

    DOE Patents [OSTI]

    Glenn, D.F.; Suciu, D.F.; Harris, T.L.; Ingram, J.C.

    1993-04-06

    This invention relates to a method and apparatus for removing heavy metals from waste water, soils, or process streams by electrolytic cell means. The method includes cooling a cell cathode to form an ice layer over the cathode and then applying an electric current to deposit a layer of the heavy metal over the ice. The metal is then easily removed after melting the ice. In a second embodiment, the same ice-covered electrode can be employed to form powdered metals.

  16. Ice electrode electrolytic cell

    DOE Patents [OSTI]

    Glenn, David F. (Idaho Falls, ID); Suciu, Dan F. (Idaho Falls, ID); Harris, Taryl L. (Idaho Falls, ID); Ingram, Jani C. (Idaho Falls, ID)

    1993-01-01

    This invention relates to a method and apparatus for removing heavy metals from waste water, soils, or process streams by electrolytic cell means. The method includes cooling a cell cathode to form an ice layer over the cathode and then applying an electric current to deposit a layer of the heavy metal over the ice. The metal is then easily removed after melting the ice. In a second embodiment, the same ice-covered electrode can be employed to form powdered metals.

  17. Mine roof bolt

    SciTech Connect (OSTI)

    Gillespie, H.D.

    1993-07-27

    A mine roof bolt is described comprising: (a) a length of multi-strand cable defining a bolt shank; (b) a tapered plug comprising a body portion having an internal bore and a frusto-conical outer surface essentially concentric with said internal bore, said tapered plug being mounted about an end of said cable at said internal bore; and (c) an internally tapered drive collar having a frusto-conical inner surface that engages said frusto-conical outer surface of said tapered plug, and having an outer surface defining a drive head that accepts a driving mechanism for rotating and linearly translating said bolt, wherein said tapered plug is mounted on an end of said cable, and said drive collar is pressed down upon said tapered plug, forcing said tapered plug against said cable, such that said drive collar, said tapered plug, and said cable, when fitted tightly together, define said mine roof bolt.

  18. DOE Science Showcase - Cool roofs, cool research, at DOE | OSTI...

    Office of Scientific and Technical Information (OSTI)

    Cool roofs, cool research, at DOE Science Accelerator returns cool roof documents from 6 ... for Selecting Cool Roofs DOE Cool Roof Calculator Visit the Science Showcase homepage.

  19. Mine roof supporting system

    SciTech Connect (OSTI)

    Curry, P.F.

    1981-06-23

    A stabilizing arrangement for mine roof support systems of the type in which a series of support units, each including a transverse beam supported at opposite ends by extensible props, are interconnected by extensible struts in a manner to be selfadvancing by alternate retraction of support units from a roof supporting condition and extension of the struts to advance such retracted units relative to others of such units which are in an extended roof engaging condition. The connection of each prop to the beam in a given unit is pivotal to allow deflection of the beam and props of a supporting unit from a normal perpendicular relationship under load. The stabilizing means restores the props and beam to a normal perpendicular relationship for advancing movement of each support unit. The supporting units are further stabilized relative to the struts by prop supporting brackets permitting canting movement of the props from a perpendicular relationship with respect to the struts but maintaining the props in a generally upright position for unit advance.

  20. Accelerated Aging of Roofing Surfaces

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

    Accelerated aging of roofing surfaces Hugo Destaillats, Ph.D. Lawrence Berkeley National ... H. Laboratory method mimicking natural soiling and weathering of outdoor surfaces. Ser. ...

  1. Cool Roofs | Department of Energy

    Energy Savers [EERE]

    How they can be made cool: Reformulate or coat black membranes to make them reflective. ... Tips: energy efficient roofs Energy efficient home design Whole-house systems approach ...

  2. Mine roof geology information system

    SciTech Connect (OSTI)

    Peng, S.S.; Sasaoka, T.; Tang, D.X.; Wilson, Y.; Wilson, G.

    2005-05-01

    A project sponsored by the US Department of Energy under the Industry of Future (Mining) program was initiated five years ago. In this project a patented drill control unit (DCU) installed DIN. the J.H. Flecher & Co.'s roof bolter was used to record the drilling parameter for experiments conducted in the mines and laboratory. Today, the drilling parameters have been recorded for more than 1,000 roof bolt holes. This article summarizes the results to date including the methods for determining quantitatively the location of voids/fractures and estimation of roof rock strength from the recorded roof bolter drilling parameters. 8 figs., 2 tabs.

  3. Cool Roofs Webinar | Department of Energy

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

    Cool Roofs Webinar Cool Roofs Webinar On April 11, 2011, Blaise Stoltenberg and Kosol Kiatreungwattana of the National Renewable Energy Laboratory presented a Webinar about roofs that are designed to maintain a lower roof temperature than traditional roofs do, in order to reduce energy bills by decreasing air conditioning needs, improve indoor thermal comfort, and decrease room operating temperature to try to extend roof service life. It's one of the presentations in a series of Sustainable

  4. Roof control system

    SciTech Connect (OSTI)

    Stankus, J.C.

    1993-08-03

    Roof control system for underground strata is described, comprising: (a) an elongated bolt adapted for insertion into a hole bored in underground strata; (b) anchor means for securely anchoring the bolt in the hole at a location where a significant length of the bolt remains between the opening of the borehole and the anchor means; (c) tension means for placing said significant length of said bolt in tension by rotating the bolt at a predetermined torque, the torque means including a plate mounted on the bolt and located adjacent to the outer surface of the strata, and a nut means on the end of the bolt for engaging the plate; (d) tension/torque adjustment means for selectively adjusting friction between adjacent surfaces which rub against each other when the bolt is rotated, whereby the tension/torque ratio of the bolt is selected to match the desired level for a particular type of underground strata, the tension/torque adjustment means including an array of friction reducing washers with different contact surface areas, for location between the nut means and plate. A method of mine control for underground strata is also described using this roof bolt.

  5. OCR Solar Roofing Inc | Open Energy Information

    Open Energy Info (EERE)

    OCR Solar Roofing Inc Jump to: navigation, search Name: OCR Solar & Roofing Inc Place: Vacaville, California Product: US installer of turnkey PV rooftops, focussing on the Northern...

  6. Solar Roofing Systems Inc | Open Energy Information

    Open Energy Info (EERE)

    Inc Place: Aurora, Ontario, Canada Zip: L4G 3S8 Product: Manufactures and develops photovoltaic roofing and portable products. References: Solar Roofing Systems Inc1 This...

  7. Measuring mine roof bolt strains

    SciTech Connect (OSTI)

    Steblay, Bernard J.

    1986-01-01

    A mine roof bolt and a method of measuring the strain in mine roof bolts of this type are disclosed. According to the method, a flat portion on the head of the mine roof bolt is first machined. Next, a hole is drilled radially through the bolt at a predetermined distance from the bolt head. After installation of the mine roof bolt and loading, the strain of the mine roof bolt is measured by generating an ultrasonic pulse at the flat portion. The time of travel of the ultrasonic pulse reflected from the hole is measured. This time of travel is a function of the distance from the flat portion to the hole and increases as the bolt is loaded. Consequently, the time measurement is correlated to the strain in the bolt. Compensation for various factors affecting the travel time are also provided.

  8. Sustainable roofs with real energy savings

    SciTech Connect (OSTI)

    Christian, J.E.; Petrie, T.W.

    1996-12-31

    This paper addresses the general concept of sustainability and relates it to the building owner`s selection of a low-slope roof. It offers a list of performance features of sustainable roofs. Experiences and data relevant to these features for four unique roofs are then presented which include: self-drying systems, low total equivalent warming foam insulation, roof coatings and green roofs. The paper concludes with a list of sustainable roofing features worth considering for a low-slope roof investment. Building owners and community developers are showing more interest in investing in sustainability. The potential exists to design, construct, and maintain roofs that last twice as long and reduce the building space heating and cooling energy loads resulting from the roof by 50% (based on the current predominant design of a 10-year life and a single layer of 1 to 2 in. (2.5 to 5.1 cm) of insulation). The opportunity to provide better low-slope roofs and sell more roof maintenance service is escalating. The general trend of outsourcing services could lead to roofing companies` owning the roofs they install while the traditional building owner owns the rest of the building. Such a situation would have a very desirable potential to internalize the costs of poor roof maintenance practices and high roof waste disposal costs, and to offer a profit for installing roofs that are more sustainable. 14 refs., 12 figs.

  9. Oklahoma Tribe to Install Solar Roof

    Broader source: Energy.gov [DOE]

    An Indian tribe in Anadarko, Oklahoma is installing solar panel roofs on two tribal government buildings.

  10. Biogeochemistry in Sea Ice: CICE model developments

    SciTech Connect (OSTI)

    Jeffery, Nicole; Hunke, Elizabeth; Elliott, Scott; Turner, Adrian

    2012-06-18

    Polar primary production unfolds in a dynamic sea ice environment, and the interactions of sea ice with ocean support and mediate this production. In spring, for example, fresh melt water contributes to the shoaling of the mixed layer enhancing ice edge blooms. In contrast, sea ice formation in the fall reduces light penetration to the upper ocean slowing primary production in marine waters. Polar biogeochemical modeling studies typically consider these types of ice-ocean interactions. However, sea ice itself is a biogeochemically active medium, contributing a significant and, possibly, essential source of primary production to polar regions in early spring and fall. Here we present numerical simulations using the Los Alamos Sea Ice Model (CICE) with prognostic salinity and sea ice biogeochemistry. This study investigates the relationship between sea ice multiphase physics and sea ice productivity. Of particular emphasis are the processes of gravity drainage, melt water flushing, and snow loading. During sea ice formation, desalination by gravity drainage facilitates nutrient exchange between ocean and ice maintaining ice algal blooms in early spring. Melt water flushing releases ice algae and nutrients to underlying waters limiting ice production. Finally, snow loading, particularly in the Southern Ocean, forces sea ice below the ocean surface driving an upward flow of nutrient rich water into the ice to the benefit of interior and freeboard communities. Incorporating ice microphysics in CICE has given us an important tool for assessing the importance of these processes for polar algal production at global scales.

  11. Accelerated Aging of Roofing Materials

    Broader source: Energy.gov [DOE]

    This project aims to reduce the time to rate aged materials from three years to a few days, which will speed next-generation cool roofing materials to market.

  12. Roof Separation Highlights Bolting Priority

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

    WIPP UPDATE: January 21, 2015 Roof Separation Highlights Bolting Priority On January 15, Mining and Ground Control Engineers at WIPP discovered that a portion of the ceiling in the Panel 3 access drift had fallen in a restricted access area. The roof fall was discovered during routine ground control and bulkhead inspections conducted by WIPP geotechnical staff, and the section that fell was estimated to be approximately 8' long by 8'wide and 24" thick. Access to this area has been

  13. Versatile roof bolt assembly

    SciTech Connect (OSTI)

    Hipkins, E.C. Sr.; Locotos, F.M.

    1987-11-03

    In an anchor bolt assembly of the type used in mine roofs and the like in which the anchor bolt assembly is positioned in a bore hole of a rock formation, where the bolt assembly includes an elongated bolt shaft with an upper end and with a head on a lower end, wherein a quick-setting resin cartridge is positioned in the bore hole above the upper end of the bolt shaft, and wherein the anchor bolt assembly is secured to the rock formation by at least the quick-setting resin, the improvement is described comprising an entrant plug provided at the upper end of the bolt shaft and adapted to rupture the resin cartridge and an elongated helical coil external of and surrounding the bolt shaft. It has a direction of coil for mixing the quick-setting resin and urging the quick-setting resin upwardly toward the upper end while the bolt shaft is rotated in one continuous direction. The helical coil is disposed below the entrant plug and connected to the entrant plug or the bolt shaft and extending a substantial length along the bolt shaft to achieve the mixing.

  14. Covered Product Category: Cool Roof Products | Department of...

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

    High emittance lowers roof temperature by increasing the release of heat by thermal radiation. To ensure a high-emittance roof, avoid unpainted metal roofs and aluminum coatings. ...

  15. Roof screening for underground coal mines: recent developments

    SciTech Connect (OSTI)

    Compton, C.S.; Gallagher, S.; Molinda, G.M.; Mark, C.; Wilson, G.

    2008-06-15

    The use of screens to control falls of the immediate roof or roof skin (that is between the installed primary and secondary roof supports) is described. 5 figs.

  16. Guidelines for Selecting Cool Roofs | Department of Energy

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

    Guidelines for Selecting Cool Roofs Guidelines for Selecting Cool Roofs Guide covers how to understand, evaluate, and implement cool roof technologies. PDF icon coolroofguide.pdf ...

  17. Cool Roofs Lead to Cooler Cities | Department of Energy

    Office of Environmental Management (EM)

    ... Roofs at DOE and Across the Federal Government Energy Department Completes Cool Roof Installation on DC Headquarters Building to Save Money by Saving Energy Energy 101: Cool Roofs

  18. SCE Roof Project Solar Power Plant | Open Energy Information

    Open Energy Info (EERE)

    SCE Roof Project Solar Power Plant Jump to: navigation, search Name SCE Roof Project Solar Power Plant Facility SCE Roof Project Sector Solar Facility Type Photovoltaic Developer...

  19. Cool Roofs | Y-12 National Security Complex

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

    Cool Roofs Cool Roofs Posted: July 18, 2012 - 1:59pm | Y-12 Report | Volume 9, Issue 1 | 2012 Hot, sunny days call for light-colored clothing to reflect the heat. As it turns out, the same principle works for roofs. Consider the results from a Lawrence Berkeley National Laboratory study in Austin, Texas, which measured a dark roof to average a whopping 43 degrees hotter than a light roof. The hotter the roof, the hotter the building becomes, and the more air-conditioning is needed - 11 percent,

  20. EVALUATION OF ROOF BOLTING REQUIREMENTS BASED ON IN-MINE ROOF BOLTER DRILLING

    SciTech Connect (OSTI)

    Syd S. Peng

    2003-04-15

    Roof bolting is the most popular method for underground openings in the mining industry, especially in the bedded deposits such as coal, potash, salt etc. In fact, all U.S. underground coal mine entries are roof-bolted as required by law. However, roof falls still occur frequently in the roof bolted entries. The two possible reasons are: the lack of knowledge of and technology to detect the roof geological conditions in advance of mining, and lack of roof bolting design criteria for modern roof bolting systems. This research is to develop a method for predicting the roof geology and stability condition in real time during roof bolting operation. Based on such information, roof bolting design criteria for modern roof bolting systems will be developed for implementation in real time. More field tests have been performed. A trendline analysis method has been developed. This method would improve the accuracy in detecting the locations of fractures and in determining the rock strength.

  1. EVALUATION OF ROOF BOLTING REQUIREMENTS BASED ON IN-MINE ROOF BOLTER DRILLING

    SciTech Connect (OSTI)

    Syd S. Peng

    2002-10-15

    Roof bolting is the most popular method for underground openings in the mining industry, especially in the bedded deposits such as coal, potash, salt etc. In fact, all U.S. underground coal mine entries are roof-bolted as required by law. However, roof falls still occur frequently in the roof bolted entries. The two possible reasons are: the lack of knowledge of and technology to detect the roof geological conditions in advance of mining, and lack of roof bolting design criteria for modern roof bolting systems. This research is to develop a method for predicting the roof geology and stability condition in real time during roof bolting operation. Based on such information, roof bolting design criteria for modern roof bolting systems will be developed for implementation in real time. Additional field tests have been performed in this quarter. The development of the data interpretation methodology and other related tasks are still continuing.

  2. EVALUATION OF ROOF BOLTING REQUIREMENTS BASED ON IN-MINE ROOF BOLTER DRILLING

    SciTech Connect (OSTI)

    Syd S. Peng

    2003-01-15

    Roof bolting is the most popular method for underground openings in the mining industry, especially in the bedded deposits such as coal, potash, salt etc. In fact, all U.S. underground coal mine entries are roof-bolted as required by law. However, roof falls still occur frequently in the roof bolted entries. The two possible reasons are: the lack of knowledge of and technology to detect the roof geological conditions in advance of mining, and lack of roof bolting design criteria for modern roof bolting systems. This research is to develop a method for predicting the roof geology and stability condition in real time during roof bolting operation. Based on such information, roof bolting design criteria for modern roof bolting systems will be developed for implementation in real time. Additional field tests have been performed. It is found that the drilling power can be used as a supplementary method for detecting voids/fractures and rock interfaces.

  3. Project Overcoat An Exploration of Exterior Insulation Strategies for 1- Story Roof Applications in Cold Climates

    SciTech Connect (OSTI)

    Ojczyk, Cindy; Mosiman, Garrett; Huelman, Pat; Schirber, Tom; Yost, Peter; Murry, Tessa

    2013-04-01

    The development of an alternative method to interior-applied insulation strategies or exterior applied band-aids such as heat tapes and ice belts may help reduce energy needs of millions of 1-1/2 story homes while reducing the risk of ice dam formation. A potential strategy for energy improvement of the roof is borrowed from new construction best practices: Here an overcoat of a continuous air, moisture, and thermal barrier is applied on the outside of the roof structure for improved overall performance. The continuous insulation of this approach facilitates a reduction in thermal bridging which could further reduce energy consumption and bring existing homes closer to meeting the Building America goals for energy reduction. Research favors an exterior approach to deep energy retrofits and ice dam prevention in existing homes. The greatest amount of research focuses on whole house deep energy retrofits leaving a void in roof-only applications. The research is also void of data supporting the hygrothermal performance, durability, constructability, and cost of roof-only exterior overcoat strategies. Yet, contractors interviewed for this report indicate an understanding that exterior approaches are most promising for mitigating ice dams and energy loss and are able to sell these strategies to homeowners.

  4. Advanced Energy Efficient Roof System

    SciTech Connect (OSTI)

    Jane Davidson

    2008-09-30

    Energy consumption in buildings represents 40 percent of primary U.S. energy consumption, split almost equally between residential (22%) and commercial (18%) buildings.1 Space heating (31%) and cooling (12%) account for approximately 9 quadrillion Btu. Improvements in the building envelope can have a significant impact on reducing energy consumption. Thermal losses (or gains) from the roof make up 14 percent of the building component energy load. Infiltration through the building envelope, including the roof, accounts for an additional 28 percent of the heating loads and 16 percent of the cooling loads. These figures provide a strong incentive to develop and implement more energy efficient roof systems. The roof is perhaps the most challenging component of the building envelope to change for many reasons. The engineered roof truss, which has been around since 1956, is relatively low cost and is the industry standard. The roof has multiple functions. A typical wood frame home lasts a long time. Building codes vary across the country. Customer and trade acceptance of new building products and materials may impede market penetration. The energy savings of a new roof system must be balanced with other requirements such as first and life-cycle costs, durability, appearance, and ease of construction. Conventional residential roof construction utilizes closely spaced roof trusses supporting a layer of sheathing and roofing materials. Gypsum board is typically attached to the lower chord of the trusses forming the finished ceiling for the occupied space. Often in warmer climates, the HVAC system and ducts are placed in the unconditioned and otherwise unusable attic. High temperature differentials and leaky ducts result in thermal losses. Penetrations through the ceilings are notoriously difficult to seal and lead to moisture and air infiltration. These issues all contribute to greater energy use and have led builders to consider construction of a conditioned attic. The

  5. Rehab guide: Roofs. Volume 3

    SciTech Connect (OSTI)

    1999-03-01

    Nine volumes will eventually make up The Rehab Guide in its entirety, and they are listed on the back cover of this volume. Each one is devoted to distinct elements of the house, and within each volume is a range of issues that are common to that element of home rehabilitation work. This volume, Roofs, for example, covers the major roofing systems including framing and sheathing; protective strategies such as underlayments and flashing; energy and air infiltration issues; roofing materials; and gutters and down-spouts. Each volume addresses a wide range techniques, materials, and tools, and recommendations based on regional differences around the country. Throughout The Rehab Guide, special attention is given to issues related to energy efficiency, sustainability, and accessibility.

  6. Self advancing mine roof supports

    SciTech Connect (OSTI)

    Seddon, J.; Jones, F.

    1985-03-19

    A self-advancing mine-roof-support for use in or aligned with a main roadway or gate has a floor-engaging part and a roof engaging part spaced apart by extensible load-bearing prop or jack means, and engagement means for a face-conveyor and a transversely acting transfer conveyor whereby their relative positions are constrained to facilitate discharge of mineral from one conveyor to the other. The engagement means for the face conveyor comprises sliding anchor beams that assure maintenance of the relative attitudes of the support and the face conveyor and the transfer conveyor is held fore and aft of the support.

  7. IDENTIFYING ROOF FALL PREDICTORS USING FUZZY CLASSIFICATION

    SciTech Connect (OSTI)

    Bertoncini, C. A.; Hinders, M. K.

    2010-02-22

    Microseismic monitoring involves placing geophones on the rock surfaces of a mine to record seismic activity. Classification of microseismic mine data can be used to predict seismic events in a mine to mitigate mining hazards, such as roof falls, where properly bolting and bracing the roof is often an insufficient method of preventing weak roofs from destabilizing. In this study, six months of recorded acoustic waveforms from microseismic monitoring in a Pennsylvania limestone mine were analyzed using classification techniques to predict roof falls. Fuzzy classification using features selected for computational ease was applied on the mine data. Both large roof fall events could be predicted using a Roof Fall Index (RFI) metric calculated from the results of the fuzzy classification. RFI was successfully used to resolve the two significant roof fall events and predicted both events by at least 15 hours before visual signs of the roof falls were evident.

  8. Energy 101: Cool Roofs | Department of Energy

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

    In this edition of Energy 101 we take a look at one of Secretary Chu's favorite energy efficiency techniques, cool roofs. Traditional dark-colored roofing materials absorb a great ...

  9. Evaluation of Roof Bolting Requirements Based on In-Mine Roof Bolter Drilling

    SciTech Connect (OSTI)

    Syd S. Peng

    2005-10-01

    Roof bolting is the most popular method for underground openings in the mining industry, especially in the bedded deposits such as coal. In fact, all U.S. underground coal mine entries are roof-bolted as required by law. However, roof falls still occur frequently in the roof bolted entries. The two possible reasons are: the lack of knowledge of and technology to detect the roof geological conditions in advance of mining, and lack of roof bolting design criteria for modern roof bolting systems. This research is to develop a method for predicting the roof geology and stability condition in real time during roof bolting operation. Based on this information, roof bolting design criteria for modern roof bolting systems will be developed for implementation in real time. For the prediction of roof geology and stability condition in real time, a micro processor was used and a program developed to monitor and record the drilling parameters of roof bolter. These parameters include feed pressure, feed flow (penetration rate), rotation pressure, rotation rate, vacuum pressure, oil temperature of hydraulic circuit, and signals for controlling machine. From the results of a series of laboratory and underground tests so far, feed pressure is found to be a good indicator for identifying the voids/fractures and estimating the roof rock strength. The method for determining quantitatively the location and the size of void/fracture and estimating the roof rock strength from the drilling parameters of roof bolter was developed. Also, a set of computational rules has been developed for in-mine roof using measured roof drilling parameters and implemented in MRGIS (Mine Roof Geology Information System), a software package developed to allow mine engineers to make use of the large amount of roof drilling parameters for predicting roof geology properties automatically. For the development of roof bolting criteria, finite element models were developed for tensioned and fully grouted bolting

  10. Roof bolt assembly having a sealing plug for preventing a deterioration of the mine roof

    SciTech Connect (OSTI)

    Unrug, K.F.; Thompson, E.D.; Nandy, S.K.

    1987-09-15

    This patent describes a roof bolt assembly for preserving the natural geological structure of a mine roof which consists of an elongated bolt rod with first and second distal ends, an expandable anchor threaded on the first end for operatively engaging the walls of a roof bolt hole bored in the mine roof at points inboard of the roof surface, a bolt head on the second end of the bolt rod, and a roof plate sandwiched between the roof surface and the bolt head. The entire assembly is pre-tensioned to tightly hold the roof plate against the roof surface. The hole bored in the roof is larger in diameter than the diameter of the roof bolt rod defining an annular space around the rod. The improvement comprises sealing means totally disposed within the annular space adjacent the second end of the bolt but spaced from the roof plate. The sealing means further being spaced from the roof surface such that a gap is formed between the roof surface and the sealing means. The sealing means preclude the entrance of air and moisture into the hole and the annular space around the rod is generally free from material in a region between the anchor and the sealing means such that the bolt is generally out of contact with the mine roof in this region.

  11. Demonstration of energy savings of cool roofs

    SciTech Connect (OSTI)

    Konopacki, S.; Gartland, L.; Akbari, H.; Rainer, L.

    1998-06-01

    Dark roofs raise the summertime air-conditioning demand of buildings. For highly-absorptive roofs, the difference between the surface and ambient air temperatures can be as high as 90 F, while for highly-reflective roofs with similar insulative properties, the difference is only about 20 F. For this reason, cool roofs are effective in reducing cooling energy use. Several experiments on individual residential buildings in California and Florida show that coating roofs white reduces summertime average daily air-conditioning electricity use from 2--63%. This demonstration project was carried out to address some of the practical issues regarding the implementation of reflective roofs in a few commercial buildings. The authors monitored air-conditioning electricity use, roof surface temperature, plenum, indoor, and outdoor air temperatures, and other environmental variables in three buildings in California: two medical office buildings in Gilroy and Davis and a retail store in San Jose. Coating the roofs of these buildings with a reflective coating increased the roof albedo from an average of 0.20--0.60. The roof surface temperature on hot sunny summer afternoons fell from 175 F--120 F after the coating was applied. Summertime average daily air-conditioning electricity use was reduced by 18% (6.3 kWh/1000ft{sup 2}) in the Davis building, 13% (3.6 kWh/1000ft{sup 2}) in the Gilroy building, and 2% (0.4 kWh/1000ft{sup 2}) in the San Jose store. In each building, a kiosk was installed to display information from the project in order to educate and inform the general public about the environmental and energy-saving benefits of cool roofs. They were designed to explain cool-roof coating theory and to display real-time measurements of weather conditions, roof surface temperature, and air-conditioning electricity use. 55 figs., 15 tabs.

  12. EVALUATION OF ROOF BOLTING REQUIREMENTS BASED ON IN-MINE ROOF BOLTER DRILLING

    SciTech Connect (OSTI)

    Syd S. Peng

    2001-10-15

    Roof bolting is the most popular method for underground openings in the mining industry, especially in the bedded deposits such as coal, potash, salt etc. In fact, all U.S. underground coal mine entries are roof-bolted as required by law. However, roof falls still occur frequently in the roof bolted entries. The two possible reasons are: the lack of knowledge of and technology to detect the roof geological conditions in advance of mining, and lack of roof bolting design criteria for modern roof bolting systems. This research is to develop a method for predicting the roof geology and stability condition in real time during roof bolting operation. Based on such information, roof bolting design criteria for modern roof bolting systems will be developed for implementation in real time. The retrofitting works for a dedicated roof bolter for this research has been completed. The laboratory tests performed using this machine on simulated roof blocks have been conducted. The analysis performed on the testing data showed promising signs to detect the rock interface, fractures, as well as the rock types. The other tasks were progressing as planned.

  13. List of Roofs Incentives | Open Energy Information

    Open Energy Info (EERE)

    Central Air conditioners CustomOthers pending approval Heat pumps Lighting Roofs Photovoltaics Yes Electric Efficiency Standard (Indiana) Energy Efficiency Resource...

  14. Next Generation Attics and Roof Systems

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

    ... of Buildings, XII, proceedings of ASHRAE THERM X, Clearwater, FL., Dec. 2013. Olsen, R., Miller, W. and Graves, R. 2013. "The Equivalent Thermal Resistance of Tile Roofs ...

  15. Lafarge Roofing Ltd | Open Energy Information

    Open Energy Info (EERE)

    Kingdom Zip: RH4 1TG Product: Distributes and installs roofing tiles, including photovoltaic ones. Coordinates: 48.231575, -101.134114 Show Map Loading map......

  16. Energy 101: Cool Roofs | Department of Energy

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

    Also featured in this video are green roofs, which grow vegetation on top of a building to provide several benefits, including reduced energy use, reduced air pollution and ...

  17. Cool Roof Calculator | Open Energy Information

    Open Energy Info (EERE)

    TOOL Name: Cool Roof Calculator AgencyCompany Organization: Oak Ridge National Laboratory Sector: Energy Focus Area: Buildings, Energy Efficiency Resource Type: Online...

  18. Building America Case Study: Field Testing an Unvented Roof with...

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

    multiple roof ridges (both diffusion vent and unvented), hips, and roof-wall interfaces. ... Some roof-wall interfaces showed moderately high MCs; this might be because of moisture ...

  19. New Cool Roof Coatings and Affordable Cool Color Asphalt

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

    New Cool Roof Coatings and Affordable Cool Color Asphalt Shingles Meng-Dawn Cheng Oak ... roof coatings and asphalt shingles to reduce energy consumption of new and existing roofs. ...

  20. Project Overcoat - An Exploration of Exterior Insulation Strategies for 1-1/2-Story Roof Applications in Cold Climates

    SciTech Connect (OSTI)

    Ojczyk, Cindy; Mosiman, Garrett; Huelman, Pat; Schirber, Tom; Yost, Peter; Murry, Tessa

    2013-04-01

    The development of an alternative method to interior-applied insulation strategies or exterior applied 'band-aids' such as heat tapes and ice belts may help reduce energy needs of millions of 1-1/2 story homes while reducing the risk of ice dam formation. A potential strategy for energy improvement of the roof is borrowed from new construction best practices: Here an 'overcoat' of a continuous air, moisture, and thermal barrier is applied on the outside of the roof structure for improved overall performance. The continuous insulation of this approach facilitates a reduction in thermal bridging which could further reduce energy consumption and bring existing homes closer to meeting the Building America goals for energy reduction. Research favors an exterior approach to deep energy retrofits and ice dam prevention in existing homes. The greatest amount of research focuses on whole house deep energy retrofits leaving a void in roof-only applications. The research is also void of data supporting the hygrothermal performance, durability, constructability, and cost of roof-only exterior overcoat strategies. Yet, contractors interviewed for this report indicate an understanding that exterior approaches are most promising for mitigating ice dams and energy loss and are able to sell these strategies to homeowners.

  1. Lightweight, self-ballasting photovoltaic roofing assembly

    DOE Patents [OSTI]

    Dinwoodie, Thomas L.

    2006-02-28

    A photovoltaic roofing assembly comprises a roofing membrane (102), a plurality of photovoltaic modules (104, 106, 108) disposed as a layer on top of the roofing membrane (102), and a plurality of pre-formed spacers, pedestals or supports (112, 114, 116, 118, 120, 122) which are respectively disposed below the plurality of photovoltaic modules (104, 106, 108) and integral therewith, or fixed thereto. Spacers (112, 114, 116, 118, 120, 122) are disposed on top of roofing membrane (102). Membrane (102) is supported on conventional roof framing, and attached thereto by conventional methods. In an alternative embodiment, the roofing assembly may have insulation block (322) below the spacers (314, 314', 315, 315'). The geometry of the pre-formed spacers (112, 114, 116, 118, 120, 122, 314, 314', 315, 315') is such that wind tunnel testing has shown its maximum effectiveness in reducing net forces of wind uplift on the overall assembly. Such construction results in a simple, lightweight, self-ballasting, readily assembled roofing assembly which resists the forces of wind uplift using no roofing penetrations.

  2. Lightweight, self-ballasting photovoltaic roofing assembly

    DOE Patents [OSTI]

    Dinwoodie, Thomas L.

    1998-01-01

    A photovoltaic roofing assembly comprises a roofing membrane (102), a plurality of photovoltaic modules (104, 106, 108) disposed as a layer on top of the roofing membrane (102), and a plurality of pre-formed spacers, pedestals or supports (112, 114, 116, 118, 120, 122) which are respectively disposed below the plurality of photovoltaic modules (104, 106, 108) and integral therewith, or fixed thereto. Spacers (112, 114, 116, 118, 120, 122) are disposed on top of roofing membrane (102). Membrane (102) is supported on conventional roof framing, and attached thereto by conventional methods. In an alternative embodiment, the roofing assembly may have insulation block (322) below the spacers (314, 314', 315, 315'). The geometry of the preformed spacers (112, 114, 116, 118, 120, 122, 314, 314', 315, 315') is such that wind tunnel testing has shown its maximum effectiveness in reducing net forces of wind uplift on the overall assembly. Such construction results in a simple, lightweight, self-ballasting, readily assembled roofing assembly which resists the forces of wind uplift using no roofing penetrations.

  3. Lightweight, self-ballasting photovoltaic roofing assembly

    DOE Patents [OSTI]

    Dinwoodie, T.L.

    1998-05-05

    A photovoltaic roofing assembly comprises a roofing membrane (102), a plurality of photovoltaic modules (104, 106, 108) disposed as a layer on top of the roofing membrane (102), and a plurality of pre-formed spacers, pedestals or supports (112, 114, 116, 118, 120, 122) which are respectively disposed below the plurality of photovoltaic modules (104, 106, 108) and integral therewith, or fixed thereto. Spacers (112, 114, 116, 118, 120, 122) are disposed on top of roofing membrane (102). Membrane (102) is supported on conventional roof framing, and attached thereto by conventional methods. In an alternative embodiment, the roofing assembly may have insulation block (322) below the spacers (314, 314', 315, 315'). The geometry of the preformed spacers (112, 114, 116, 118, 120, 122, 314, 314', 315, 315') is such that wind tunnel testing has shown its maximum effectiveness in reducing net forces of wind uplift on the overall assembly. Such construction results in a simple, lightweight, self-ballasting, readily assembled roofing assembly which resists the forces of wind uplift using no roofing penetrations.

  4. Fluorescent Pigments for High-Performance Cool Roofing

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

    Target Market and Audience: The target market is the steep metal roof market. Residential market roofs in ... Spectrometer determines SR * Temperature measurements taken outside in ...

  5. Tips: Energy-Efficient Roofs | Department of Energy

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

    carefully assess your property and consult a professional before deciding to install a green roof. Learn More Energy-Efficient Home Design Cool Roofs Financing Energy-Efficient...

  6. Comparison of Software Models for Energy Savings from Cool Roofs...

    Office of Scientific and Technical Information (OSTI)

    Title: Comparison of Software Models for Energy Savings from Cool Roofs A web-based Roof ... This tool employs modern web technologies, usability design, and national average defaults ...

  7. Hawaii Marine Base Installs Solar Roofs | Department of Energy

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

    Lorelei Laird Writer, Energy Empowers What does this project do? Marine Corps Base Hawaii replaced roofs on two buildings with polyvinyl chloride membrane 'cool' roofs and solar...

  8. Secretary Chu Announces Steps to Implement Cool Roofs at DOE...

    Energy Savers [EERE]

    ... Labs Join with Dow Chemical to Develop Next-Generation Cool Roofs Energy Department Completes Cool Roof Installation on DC Headquarters Building to Save Money by Saving Energy

  9. Daylighter Daily Solar Roof Light | Open Energy Information

    Open Energy Info (EERE)

    Daylighter Daily Solar Roof Light Jump to: navigation, search Name: Daylighter Daily Solar Roof Light Address: 1991 Crocker Road, Suite 600 Place: Cleveland, Ohio Zip: 44145...

  10. Tips: Energy-Efficient Roofs | Department of Energy

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

    deciding to install a green roof. Learn More Energy efficient home design Cool roofs Incentives and financing for energy efficient homes Whole-house systems approach ...

  11. Tips: Energy-Efficient Roofs | Department of Energy

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

    your property and consult a professional before deciding to install a green roof. Learn More Energy efficient home design Cool roofs Incentives and financing for energy ...

  12. Measuring mine roof bolt strains

    SciTech Connect (OSTI)

    Steblay, B.J.

    1986-07-22

    A method is described of measuring the strain in mine roof bolts comprising the steps of: machining a flat portion on the head of the bolt before loading; drilling a reflector hole radially through the diameter of the bolt at a predetermined distance from the bolt head before loading, the ratio of the diameter of the hole to the diameter of the bolt being less than 0.10 to prevent weakening of the loaded bolt; generating an ultrasonic pulse at the flat portion after loading; measuring the time of travel of the ultrasonic pulse reflected from the hole, which increases as the bolt is loaded; and correlating the time measurement of the strain in the bolt.

  13. Passive ice freezing-releasing heat pipe

    DOE Patents [OSTI]

    Gorski, Anthony J.; Schertz, William W.

    1982-01-01

    A heat pipe device has been developed which permits completely passive ice formation and periodic release of ice without requiring the ambient temperature to rise above the melting point of water. This passive design enables the maximum amount of cooling capacity to be stored in the tank.

  14. Cool Roofs Through Time and Space

    SciTech Connect (OSTI)

    Levinson, Ronnen

    2014-10-17

    Ronnen Levinson, from the Lab's Heat Island Group, presents his research on cool roofs and introduces the California Cities Albedo Map at our '8 Big Ideas' Science at the Theater event on October 8th, 2014, in Oakland, California

  15. Roof Installation at 2009 Solar Decathlon

    Broader source: Energy.gov [DOE]

    Iowa State student Timothy Lentz, foreground, and Team Alberta student Leah Battersdy, right, work on the roofs of their houses during the U.S. Department of Energy Solar Decathlon 2009.

  16. SolarRoofs com | Open Energy Information

    Open Energy Info (EERE)

    95608 Sector: Solar Product: California-based manufacturer of the patented Skyline solar water heating systems. References: SolarRoofs.com1 This article is a stub. You can help...

  17. Installation of Cool Roofs on Department of Energy Buildings | Department

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

    of Energy Installation of Cool Roofs on Department of Energy Buildings Installation of Cool Roofs on Department of Energy Buildings 2010.06.01 S-1 memo, Installation of Cool Roofs on DOE Buildings.pdf (388.81 KB) More Documents & Publications Guidelines for Selecting Cool Roofs CX-002735: Categorical Exclusion Determination Impact of Solar PV Laminate Membrane Systems on Roofs

  18. Weatherization Installer/Technician Fundamentals 2.0 - Roofing, Flashing,

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

    and Attic Ventilation Installation Needs | Department of Energy Roofing, Flashing, and Attic Ventilation Installation Needs Weatherization Installer/Technician Fundamentals 2.0 - Roofing, Flashing, and Attic Ventilation Installation Needs Roofing, Flashing, and Attic Ventilation Installation Needs - Complete (4.45 MB) Lesson Plan: Roofing, Flashing, and Attic Ventilation Installation Needs (127.32 KB) PowerPoint: Roofing, Flashing, and Attic Ventilation Installation Needs (4.39 MB) More

  19. Accelerated Aging of Roofing Materials - 2013 BTO Peer Review | Department

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

    of Energy Accelerated Aging of Roofing Materials - 2013 BTO Peer Review Accelerated Aging of Roofing Materials - 2013 BTO Peer Review Emerging Technologies Project for the 2013 Building Technologies Office's Program Peer Review emrgtech24_destaillats_040413.pdf (1.02 MB) More Documents & Publications Accelerated Aging of Roofing Materials Stay-Clean and Durable White Elastomeric Roof Coatings New Cool Roof Coatings and Affordable Cool Color Asphalt

  20. Vapor deposition of water on graphitic surfaces: Formation of amorphous ice, bilayer ice, ice I, and liquid water

    SciTech Connect (OSTI)

    Lupi, Laura; Kastelowitz, Noah; Molinero, Valeria

    2014-11-14

    Carbonaceous surfaces are a major source of atmospheric particles and could play an important role in the formation of ice. Here we investigate through molecular simulations the stability, metastability, and molecular pathways of deposition of amorphous ice, bilayer ice, and ice I from water vapor on graphitic and atomless Lennard-Jones surfaces as a function of temperature. We find that bilayer ice is the most stable ice polymorph for small cluster sizes, nevertheless it can grow metastable well above its region of thermodynamic stability. In agreement with experiments, the simulations predict that on increasing temperature the outcome of water deposition is amorphous ice, bilayer ice, ice I, and liquid water. The deposition nucleation of bilayer ice and ice I is preceded by the formation of small liquid clusters, which have two wetting states: bilayer pancake-like (wetting) at small cluster size and droplet-like (non-wetting) at larger cluster size. The wetting state of liquid clusters determines which ice polymorph is nucleated: bilayer ice nucleates from wetting bilayer liquid clusters and ice I from non-wetting liquid clusters. The maximum temperature for nucleation of bilayer ice on flat surfaces, T{sub B}{sup max} is given by the maximum temperature for which liquid water clusters reach the equilibrium melting line of bilayer ice as wetting bilayer clusters. Increasing water-surface attraction stabilizes the pancake-like wetting state of liquid clusters leading to larger T{sub B}{sup max} for the flat non-hydrogen bonding surfaces of this study. The findings of this study should be of relevance for the understanding of ice formation by deposition mode on carbonaceous atmospheric particles, including soot.

  1. Cost Analysis of Roof-Only Air Sealing and Insulation Strategies on 1 1/2-Story Homes in Cold Climates

    SciTech Connect (OSTI)

    Ojczyk, C.

    2014-12-01

    The External Thermal and Moisture Management System (ETMMS), typically seen in deep energy retrofits, is a valuable approach for the roof-only portions of existing homes, particularly the 1 1/2-story home. It is effective in reducing energy loss through the building envelope, improving building durability, reducing ice dams, and providing opportunities to improve occupant comfort and health.

  2. Cost Analysis of Roof-Only Air Sealing and Insulation Strategies on 1 1/2-Story Homes in Cold Climates

    SciTech Connect (OSTI)

    Ojczyk, C.

    2014-12-01

    The External Thermal and Moisture Management System (ETMMS), typically seen in deep energy retrofits, is a valuable approach for the roof-only portions of existing homes, particularly the 1 ½-story home. It is effective in reducing energy loss through the building envelope, improving building durability, reducing ice dams, and providing opportunities to improve occupant comfort and health.

  3. Indirect Benefits (Increased Roof Life and HVAC Savings) from...

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

    Indirect Benefits (Increased Roof Life and HVAC Savings) from a Solar PV System at the San Jos Convention Center Indirect Benefits (Increased Roof Life and HVAC Savings) from a ...

  4. Cool Roofs: An Easy Upgrade | Department of Energy

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

    Cathy Zoi Former Assistant Secretary, Office of Energy Efficiency & Renewable Energy What does this mean for me? Dark roofs can be 50 degrees hotter than light roofs. Combined with ...

  5. MSR Innovations Modular Solar Roofing | Open Energy Information

    Open Energy Info (EERE)

    search Name: MSR Innovations (Modular Solar Roofing) Place: Burnaby, British Columbia, Canada Zip: V5J 5H8 Product: British Columbia-based PV roofing systems maker. Coordinates:...

  6. Solar Domestic Water Heating: a Roof-Integrated Evaluation

    SciTech Connect (OSTI)

    2009-09-03

    This fact sheet describes an evaluation of the performance of a roof-integrated solar water heating system.

  7. DOE Science Showcase - Cool roofs, cool research, at DOE | OSTI, US Dept of

    Office of Scientific and Technical Information (OSTI)

    Energy Office of Scientific and Technical Information Cool roofs, cool research, at DOE Science Accelerator returns cool roof documents from 6 DOE Databases Executive Order on Sustainability Secretary Chu Announces Steps to Implement One Cool Roof Cool Roofs Lead to Cooler Cities Guidelines for Selecting Cool Roofs DOE Cool Roof Calculator Visit the Science Showcase homepage.

  8. Recovery and reuse of asphalt roofing waste. Final report

    SciTech Connect (OSTI)

    Desai, S.; Graziano, G.; Shepherd, P.

    1984-02-02

    Burning of asphalt roofing waste as a fuel and incorporating asphalt roofing waste in bituminous paving were identified as the two outstanding resource recovery concepts out of ten studied. Four additional concepts might be worth considering under different market or technical circumstances. Another four concepts were rated as worth no further consideration at this time. This study of the recovery of the resource represented in asphalt roofing waste has identified the sources and quantities of roofing waste. About six million cubic yards of scrap roofing are generated annually in the United States, about 94% from removal of old roofing at the job site and the remainder from roofing material production at factories. Waste disposal is a growing problem for manufacturers and contractors. Nearly all roofing waste is hauled to landfills at a considerable expense to roofing contractors and manufacturers. Recovery of the roofing waste resource should require only a modest economic incentive. The asphalt contained in roofing waste represents an energy resource of more than 7 x 10/sup 13/ Btu/year. Another 1 x 10/sup 13/ Btu/year may be contained in field-applied asphalt on commercial building roofs. The two concepts recommended by this study appear to offer the broadest applicability, the most favorable economics, and the highest potential for near-term implementation to reuse this resource.

  9. PERFORMANCE EVALUATION OF A SUSTAINABLE AND ENERGY EFFICIENT RE-ROOFING TECHNOLOGY USING FIELD-TEST DATA

    SciTech Connect (OSTI)

    Biswas, Kaushik; Miller, William A; Childs, Phillip W; Kosny, Jan; Kriner, Scott

    2011-01-01

    Three test attics were constructed to evaluate a new sustainable method of re-roofing utilizing photo-voltaic (PV) laminates, metal roofing panels, and PCM heat sink in the Envelope Systems Research Apparatus (ESRA) facility in the ORNL campus. Figure 1 is a picture of the three attic roofs located adjacent to each other. The leftmost roof is the conventional shingle roof, followed by the metal panel roof incorporating the cool-roof coating, and third from left is the roof with the PCM. On the PCM roof, the PV panels are seen as well; they're labelled from left-to-right as panels 5, 6 and 7. The metal panel roof consists of three metal panels with the cool-roof coating; in further discussion this is referred to as the infrared reflective (IRR) metal roof. The IRR metal panels reflect the incoming solar radiation and then quickly re-emit the remaining absorbed portion, thereby reducing the solar heat gain of the attic. Surface reflectance of the panels were measured using a Solar Spectrum Reflectometer. In the 0.35-2.0 {mu}m wavelength interval, which accounts for more than 94% of the solar energy, the IRR panels have an average reflectance of 0.303. In the infrared portion of the spectrum, the IRR panel reflectance is 0.633. The PCM roof consists of a layer of macro-encapsulated bio-based PCM at the bottom, followed by a 2-cm thick layer of dense fiberglass insulation with a reflective surface on top, and metal panels with pre-installed PV laminates on top. The PCM has a melting point of 29 C (84.2 F) and total enthalpy between 180 and 190 J/g. The PCM was macro-packaged in between two layers of heavy-duty plastic foil forming arrays of PCM cells. Two air cavities, between PCM cells and above the fiberglass insulation, helped the over-the-deck natural air ventilation. It is anticipated that during summer, this extra ventilation will help in reducing the attic-generated cooling loads. The extra ventilation, in conjunction with the PCM heat sink, are used to minimize

  10. Covered Product Category: Cool Roof Products

    Broader source: Energy.gov [DOE]

    FEMP provides acquisition guidance across a variety of product categories, including cool roof products, which are an ENERGY STAR®-qualified product category. Federal laws and requirements mandate that agencies meet these efficiency requirements in all procurement and acquisition actions that are not specifically exempted by law.

  11. A Cool Roof for the Iconic Cyclotron

    Broader source: Energy.gov [DOE]

    Berkeley Lab's iconic building, the Advanced Light Source — yes, the same one that had a cameo in Ang Lee’s “The Incredible Hulk” -- is getting a cool new roof. Check out the photos of the cyclotron in 1941, and now.

  12. Thrust bolting: roof bolt support apparatus

    DOE Patents [OSTI]

    Tadolini, Stephen C.; Dolinar, Dennis R.

    1992-01-01

    A method of installing a tensioned roof bolt in a borehole of a rock formation without the aid of a mechanical anchoring device or threaded tensioning threads by applying thrust to the bolt (19) as the bonding material (7') is curing to compress the strata (3) surrounding the borehole (1), and then relieving the thrust when the bonding material (7') has cured.

  13. Plug improves stability of shaly roofs

    SciTech Connect (OSTI)

    Unrug, K.F.; Nandy, S.; Thompson, E. )

    1991-04-01

    Although geologic conditions and over-stressing play major roles in roof falls, an especially common cause of falls of shaly roof is the gradual deterioration of the shale itself. The culprit in such deteriorations is the hydrophilic nature of the shale's clay mineral components, a trait causing some of the clay minerals to swell due to absorption of water from the atmosphere. Moisture enters the annular space between the bolt rod and the walls of the borehole, and then condenses on the cooler surfaces. It can then be absorbed by the shale through capillary attraction into micro cracks and bedding planes. When the condensation forms at the anchorage level, it can cause weakening of the rock, especially where the shale is under high stress with the anchor shell. To prevent migration of moisture into the roof through bolt holes, a patented plastic plug has been designed to seal the annular space between the rock and the bolt rod at the entrance of the hole. The plug consists of two halves that snap in and lock together. It can be assembled on a bolt rod in just three seconds by squeezing the two halves together just before the bolt is inserted into the bolt hole. The external and internal flanges of the plug create tight contact between the perimeter of the hole and the bolt rod, thereby sealing the annular space between the rock and the roof bolt at the entrance of the hole.

  14. Evolution of cool-roof standards in the United States

    SciTech Connect (OSTI)

    Akbari, Hashem; Akbari, Hashem; Levinson, Ronnen

    2008-07-11

    Roofs that have high solar reflectance and high thermal emittance stay cool in the sun. A roof with lower thermal emittance but exceptionally high solar reflectance can also stay cool in the sun. Substituting a cool roof for a noncool roof decreases cooling-electricity use, cooling-power demand, and cooling-equipment capacity requirements, while slightly increasing heating-energy consumption. Cool roofs can also lower citywide ambient air temperature in summer, slowing ozone formation and increasing human comfort. Provisions for cool roofs in energy-efficiency standards can promote the building- and climate-appropriate use of cool roofing technologies. Cool-roof requirements are designed to reduce building energy use, while energy-neutral cool-roof credits permit the use of less energy-efficient components (e.g., larger windows) in a building that has energy-saving cool roofs. Both types of measures can reduce the life-cycle cost of a building (initial cost plus lifetime energy cost). Since 1999, several widely used building energy-efficiency standards, including ASHRAE 90.1, ASHRAE 90.2, the International Energy Conservation Code, and California's Title 24 have adopted cool-roof credits or requirements. This paper reviews the technical development of cool-roof provisions in the ASHRAE 90.1, ASHRAE 90.2, and California Title 24 standards, and discusses the treatment of cool roofs in other standards and energy-efficiency programs. The techniques used to develop the ASHRAE and Title 24 cool-roof provisions can be used as models to address cool roofs in building energy-efficiency standards worldwide.

  15. Status of cool roof standards in the United States

    SciTech Connect (OSTI)

    Akbari, Hashem; Levinson, Ronnen

    2007-06-01

    Since 1999, several widely used building energy efficiency standards, including ASHRAE 90.1, ASHRAE 90.2, the International Energy Conservation Code, and California's Title 24 have adopted cool roof credits or requirements. We review the technical development of cool roof provisions in the ASHRAE 90.1, ASHRAE 90.2, and California Title 24 standards, and discuss the treatment of cool roofs in other standards and energy-efficiency programs. The techniques used to develop the ASHRAE and Title 24 cool roof provisions can be used as models to address cool roofs in building energy standards worldwide.

  16. Hawaii Marine Base Installs Solar Roofs | Department of Energy

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

    Marine Base Installs Solar Roofs Hawaii Marine Base Installs Solar Roofs April 2, 2010 - 2:42pm Addthis Lorelei Laird Writer, Energy Empowers What does this project do? Marine Corps Base Hawaii replaced roofs on two buildings with polyvinyl chloride membrane 'cool' roofs and solar panels. The new roofs saves $20,000 a year in energy costs. Built on the end of the Mokapu Peninsula on Oahu's northeast coast, the Marine Corps Base Hawaii (MCBH) at Kaneohe Bay gets plenty of sunlight. But harnessing

  17. Greenland Ice Sheet "Sliding" a Small Contributor to Future Sea...

    Office of Science (SC) Website

    A wide range of observations suggests that water generated by melt at the ice sheet ... vertical well-like shafts within a glacier through which water enters from the surface). ...

  18. Thrust bolting: Roof-bolt-support apparatus

    SciTech Connect (OSTI)

    Tadolini, S.C.; Dolinar, D.R.

    1991-01-01

    The invention relates to a method for installing a roof bolt in a borehole of a rock formation and more specifically to tensioning the unit without the aid of a mechanical anchoring device or threaded tensioning threads. The bolt is capable of being placed into tension along the length and the levels of active support can be controlled by varying the length of the grouted portion and the level of thrust applied to the bolt during installation.

  19. Aging and weathering of cool roofing membranes

    SciTech Connect (OSTI)

    Akbari, Hashem; Berhe, Asmeret A.; Levinson, Ronnen; Graveline,Stanley; Foley, Kevin; Delgado, Ana H.; Paroli, Ralph M.

    2005-08-23

    Aging and weathering can reduce the solar reflectance of cool roofing materials. This paper summarizes laboratory measurements of the solar spectral reflectance of unweathered, weathered, and cleaned samples collected from single-ply roofing membranes at various sites across the United States. Fifteen samples were examined in each of the following six conditions: unweathered; weathered; weathered and brushed; weathered, brushed and then rinsed with water; weathered, brushed, rinsed with water, and then washed with soap and water; and weathered, brushed, rinsed with water, washed with soap and water, and then washed with an algaecide. Another 25 samples from 25 roofs across the United States and Canada were measured in their unweathered state, weathered, and weathered and wiped. We document reduction in reflectivity resulted from various soiling mechanisms and provide data on the effectiveness of various cleaning approaches. Results indicate that although the majority of samples after being washed with detergent could be brought to within 90% of their unweathered reflectivity, in some instances an algaecide was required to restore this level of reflectivity.

  20. Airtightness Results of Roof-Only Air Sealing Strategies on 1 ½-Story Homes in Cold Climates

    SciTech Connect (OSTI)

    Ojczyk, C.; Murry, T.; Mosiman, G.

    2014-07-01

    In this second study on solutions to ice dams in 1-1/2 story homes, the NorthernSTAR Building America Partnership team analyzed five test homes located in both cold and very cold climates for air leakage reduction rates following modifications by independent contractors on owner-occupied homes. These homes were chosen for testing as they are common in Minnesota and very difficult to air seal and insulate effectively. Two projects followed a roof-only Exterior Thermal Moisture Management System (ETMMS) process. One project used an interior-only approach to roof air sealing and insulation. The remaining two projects used a deep energy retrofit approach for whole house (foundation wall, above grade wall, roof) air leakage and heat loss reduction. All were asked to provide information regarding project goals, process, and pre and post-blower door test results. Additional air leakage reduction data was provided by several NorthernSTAR industry partners for interior-applied, roof-only modifications on 1-1/2 story homes. The data represents homes in the general market as well as homes that were part of the state of Minnesota weatherization program. A goal was to compare exterior air sealing methods with interior approaches. This pool of data enabled the team to compare air tightness data from over 220 homes using similar air seal methods.

  1. Airtightness Results of Roof-Only Air Sealing Strategies on 1-1/2 Story Homes in Cold Climates

    SciTech Connect (OSTI)

    Ojczyk, C.; Murry, T.; Mosiman, G.

    2014-07-01

    In this second study on solutions to ice dams in 1-1/2 story homes, five test homes located in both cold and very cold climates were analyzed for air leakage reduction rates following modifications by independent contractors on owner-occupied homes. The reason for choosing this house type was they are very common in our area and very difficult to air seal and insulate effectively. Two projects followed a roof-only Exterior Thermal Moisture Management System (ETMMS) process. One project used an interior-only approach to roof air sealing and insulation. The remaining two projects used a deep energy retrofit approach for whole house (foundation wall, above grade wall, roof) air leakage and heat loss reduction. All were asked to provide information regarding project goals, process, and pre and post-blower door test results. Additional air leakage reduction data was provided by several NorthernSTAR Building America industry partners for interior-applied, roof-only modifications on 1-1/2 story homes. The data represents homes in the general market as well as homes that were part of the state of Minnesota weatherization program. A goal was to compare exterior air sealing methods with interior approaches. This pool of data enabled us to compare air tightness data from over 220 homes using similar air seal methods.

  2. Passive ice freezing-releasing heat pipe. [Patent application

    DOE Patents [OSTI]

    Gorski, A.J.; Schertz, W.W.

    1980-09-29

    A heat pipe device has been developed which permits completely passive ice formation and periodic release of ice without requiring the ambient temperature to rise above the melting point of water. This passive design enables the maximum amount of cooling capacity to be stored in the tank.

  3. Improving Our Environment One Roof at a Time

    Broader source: Energy.gov [DOE]

    Known by a variety of names, green roofs – which are built on top of a conventional roof and are partially or completely covered by vegetation – have been around for thousands of years and are popular in many European countries. Scientists at the Department of Energy’s National Energy Technology Laboratory are using green roofs as laboratories to investigate alternative growth media for plants that make use of waste materials generated by the fossil fuel industry.

  4. Flourescent Pigments for High-Performance Cool Roofing and Facades |

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

    Department of Energy Flourescent Pigments for High-Performance Cool Roofing and Facades Flourescent Pigments for High-Performance Cool Roofing and Facades Addthis 1 of 3 PPG Industries and Lawrence Berkeley National Laboratory are partnering to develop a new class of dark-colored pigments for cool metal roof and façade coatings that incorporate near-infrared fluorescence and reflectance to improve energy performance. Image: PPG Industries 2 of 3 Berkeley Lab Heat Island Group physicist Paul

  5. Energy Department Completes Cool Roof Installation on DC Headquarters

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

    Building to Save Money by Saving Energy | Department of Energy Completes Cool Roof Installation on DC Headquarters Building to Save Money by Saving Energy Energy Department Completes Cool Roof Installation on DC Headquarters Building to Save Money by Saving Energy December 14, 2010 - 12:00am Addthis Washington - Secretary Steven Chu today announced the completion of a new cool roof installation on the Department of Energy's Headquarters West Building. There was no incremental cost to adding

  6. Accelerated Aging of Roofing Materials | Department of Energy

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

    Accelerated Aging of Roofing Materials Accelerated Aging of Roofing Materials 1 of 2 Berkeley Lab Heat Island Group chemist Mohamad Sleiman prepares to insert clean and soiled roofing specimens into a weatherometer. The weatherometer simulates exposure to heat, moisture, and UV radiation. Image: Heat Island Group, Lawrence Berkeley National Laboratory 2 of 2 Berkeley Lab Heat Island Group chemist Mohamad Sleiman configures a weatherometer to simulate the effects of heat, moisture, and UV

  7. Cool roofs as an energy conservation measure for federal buildings

    SciTech Connect (OSTI)

    Taha, Haider; Akbari, Hashem

    2003-04-07

    We have developed initial estimates of the potential benefits of cool roofs on federal buildings and facilities (building scale) as well as extrapolated the results to all national facilities under the administration of the Federal Energy Management Program (FEMP). In addition, a spreadsheet ''calculator'' is devised to help FEMP estimate potential energy and cost savings of cool roof projects. Based on calculations for an average insulation level of R-11 for roofs, it is estimated that nationwide annual savings in energy costs will amount to $16M and $32M for two scenarios of increased roof albedo (moderate and high increases), respectively. These savings, corresponding to about 3.8 percent and 7.5 percent of the base energy costs for FEMP facilities, include the increased heating energy use (penalties) in winter. To keep the cost of conserved energy (CCE) under $0.08 kWh-1 as a nationwide average, the calculations suggest that the incremental cost for cool roofs should not exceed $0.06 ft-2, assuming that cool roofs have the same life span as their non-cool counterparts. However, cool roofs usually have extended life spans, e.g., 15-30 years versus 10 years for conventional roofs, and if the costs of re-roofing are also factored in, the cutoff incremental cost to keep CCE under $0.08 kWh-1 can be much higher. In between these two ends, there is of course a range of various combinations and options.

  8. Status of cool roof standards in the United States (Conference...

    Office of Scientific and Technical Information (OSTI)

    Since 1999, several widely used building energy efficiency standards, including ASHRAE ... and discuss the treatment of cool roofs in other standards and energy-efficiency programs. ...

  9. Next Generation Attics and Roof Systems | Department of Energy

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

    Emerging Technologies Project for the 2013 Building Technologies Office's Program Peer Review PDF icon emrgtech26miller040413.pdf More Documents & Publications New Cool Roof ...

  10. A Review of Methods for the Manufacture of Residential Roofing...

    Office of Scientific and Technical Information (OSTI)

    In climates with significant demand for cooling energy, increasing roof solar reflectance ... The report also discusses innovative methods for increasing the solar reflectance of these ...

  11. Comparison of software models for energy savings from cool roofs...

    Office of Scientific and Technical Information (OSTI)

    Comparison of software models for energy savings from cool roofs Citation Details In-Document Search This content will become publicly available on September 4, 2017 Title: ...

  12. Cool Roofs and Heat Islands | Open Energy Information

    Open Energy Info (EERE)

    Tool Summary LAUNCH TOOL Name: Cool Roofs AgencyCompany Organization: Lawrence Berkeley National Laboratory Sector: Energy Focus Area: Energy Efficiency Topics: Resource...

  13. Developing Energy Efficient Roof Systems DEERS | Open Energy...

    Open Energy Info (EERE)

    (DEERS) Place: Ripon, California Zip: 95366 Sector: Solar Product: Developer of roof top solar PV projects. Coordinates: 43.84582, -88.837054 Show Map Loading map......

  14. Secretary Chu Announces Steps to Implement Cool Roofs at DOE...

    National Nuclear Security Administration (NNSA)

    coatings to reflect more of the sun's heat, helping improve building efficiency by ... urban areas. Because they absorb so much heat, dark-colored roofs and roadways create ...

  15. New “Cool Roof Time Machine” Will Accelerate Cool Roof Deployment

    Broader source: Energy.gov [DOE]

    A collaboration led by scientists at Lawrence Berkeley National Laboratory (Berkeley Lab) has established a method to simulate soiling and weathering processes in the lab, reproducing in only a few days the solar reflectance of roofing products naturally aged for three years.

  16. High Efficiency Solar Integrated Roof Membrane Product

    SciTech Connect (OSTI)

    Partyka, Eric; Shenoy, Anil

    2013-05-15

    This project was designed to address the Solar Energy Technology Program objective, to develop new methods to integrate photovoltaic (PV) cells or modules within a building-integrated photovoltaic (BIPV) application that will result in lower installed cost as well as higher efficiencies of the encapsulated/embedded PV module. The technology assessment and development focused on the evaluation and identification of manufacturing technologies and equipment capable of producing such low-cost, high-efficiency, flexible BIPV solar cells on single-ply roofing membranes.

  17. Estimating Heat and Mass Transfer Processes in Green Roof Systems: Current Modeling Capabilities and Limitations (Presentation)

    SciTech Connect (OSTI)

    Tabares Velasco, P. C.

    2011-04-01

    This presentation discusses estimating heat and mass transfer processes in green roof systems: current modeling capabilities and limitations. Green roofs are 'specialized roofing systems that support vegetation growth on rooftops.'

  18. Building America Case Study: Cost Analysis of Roof-Only Air Sealing and Insulation Strategies on 1-1/2 Story Homes in Cold Climates, Minneapolis, MN (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2014-12-01

    The External Thermal and Moisture Management System (ETMMS), typically seen in deep energy retrofits, is a valuable approach for the roof-only portions of existing homes, particularly the 1 1/2-story home. It is effective in reducing energy loss through the building envelope, improving building durability, reducing ice dams, and providing opportunities to improve occupant comfort and health.

  19. Hygrothermal Performance of West Coast Wood Deck Roofing System

    SciTech Connect (OSTI)

    Pallin, Simon B; Kehrer, Manfred; Desjarlais, Andre Omer

    2014-02-01

    Simulations of roofing assemblies are necessary in order to understand and adequately predict actual the hygrothermal performance. At the request of GAF, simulations have been setup to verify the difference in performance between white and black roofing membrane colors in relation to critical moisture accumulation for traditional low slope wood deck roofing systems typically deployed in various western U.S. Climate Zones. The performance of these roof assemblies has been simulated in the hygrothermal calculation tool of WUFI, from which the result was evaluated based on a defined criterion for moisture safety. The criterion was defined as the maximum accepted water content for wood materials and the highest acceptable moisture accumulation rate in relation to the risk of rot. Based on the criterion, the roof assemblies were certified as being either safe, risky or assumed to fail. The roof assemblies were simulated in different western climates, with varying insulation thicknesses, two different types of wooden decking, applied with varying interior moisture load and with either a high or low solar absorptivity at the roof surface (black or white surface color). The results show that the performance of the studied roof assemblies differs with regard to all of the varying parameters, especially the climate and the indoor moisture load.

  20. Fourier analysis of conductive heat transfer for glazed roofing materials

    SciTech Connect (OSTI)

    Roslan, Nurhana Lyana; Bahaman, Nurfaradila; Almanan, Raja Noorliyana Raja; Ismail, Razidah; Zakaria, Nor Zaini

    2014-07-10

    For low-rise buildings, roof is the most exposed surface to solar radiation. The main mode of heat transfer from outdoor via the roof is conduction. The rate of heat transfer and the thermal impact is dependent on the thermophysical properties of roofing materials. Thus, it is important to analyze the heat distribution for the various types of roofing materials. The objectives of this paper are to obtain the Fourier series for the conductive heat transfer for two types of glazed roofing materials, namely polycarbonate and polyfilled, and also to determine the relationship between the ambient temperature and the conductive heat transfer for these materials. Ambient and surface temperature data were collected from an empirical field investigation in the campus of Universiti Teknologi MARA Shah Alam. The roofing materials were installed on free-standing structures in natural ventilation. Since the temperature data are generally periodic, Fourier series and numerical harmonic analysis are applied. Based on the 24-point harmonic analysis, the eleventh order harmonics is found to generate an adequate Fourier series expansion for both glazed roofing materials. In addition, there exists a linear relationship between the ambient temperature and the conductive heat transfer for both glazed roofing materials. Based on the gradient of the graphs, lower heat transfer is indicated through polyfilled. Thus polyfilled would have a lower thermal impact compared to polycarbonate.

  1. Cool Roofs Through Time and Space (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    COOL ROOF; ALBEDO; METAL; BLACK CARBON; WEATHEROMETER; SOILING APPARATUS; REFLECTION; ROOF ALBEDO Word Cloud More Like This Multimedia File size NAView Multimedia View Multimedia

  2. DOE's Oak Ridge and Lawrence Berkeley National Labs Join with Dow Chemical to Develop Next-Generation Cool Roofs

    Broader source: Energy.gov [DOE]

    Research will Lead to Improved Efficiency for Cool Roofs and Increase Cool Roof Energy Savings by Over 50 Percent

  3. Technology Solutions Case Study: Cost Analysis of Roof-Only Air Sealing and Insulation Strategies on 1-1/2 Story Homes in Cold Climates, Minneapolis, MN

    SciTech Connect (OSTI)

    2014-12-01

    This case study describes the External Thermal and Moisture Management System developed by the NorthernSTAR Building America Partnership. This system is typically used in deep energy retrofits and is a valuable approach for the roof-only portions of existing homes, particularly the 1 1/2-story home. It is effective in reducing energy loss through the building envelope, improving building durability, reducing ice dams, and providing opportunities to improve occupant comfort and health.

  4. Melt containment member

    DOE Patents [OSTI]

    Rieken, Joel R.; Heidloff, Andrew J.

    2014-09-09

    A tubular melt containment member for transient containment of molten metals and alloys, especially reactive metals and alloys, includes a melt-contacting layer or region that comprises an oxygen-deficient rare earth oxide material that is less reactive as compared to the counterpart stoichiometric rare earth oxide. The oxygen-deficient (sub-stoichiometric) rare earth oxide can comprise oxygen-deficient yttria represented by Y.sub.2O.sub.3-x wherein x is from 0.01 to 0.1. Use of the oxygen-deficient rare earth oxide as the melt-contacting layer or region material reduces reaction with the melt for a given melt temperature and melt contact time.

  5. Development of photovoltaic modules integrated with roofing materials (heat insulated roof panel)

    SciTech Connect (OSTI)

    Nitta, Y.; Hatukaiwa, T.; Yamawaki, T.; Matumura, Y.; Mizukami, S.

    1994-12-31

    The authors have started to develop low cost photovoltaic modules integrated with roofing materials for wooden houses. They made a concept of the design for the modules using amorphous silicon solar cells and produced test modules that consist of untempered surface glass, solar cells, waterproof sheet, heat insulating materials and base frames. They have primarily tested the distributed pressure resistance as a building component. When applying a load from the front surface side of the modules, a 3.6 mm deflection at the center of the specimen under 300 kg/m{sup 2} load was observed, which is equivalent to a snowfall of 1.2 meters. As a result, they have finally confirmed that modules have enough structural strength to be used as a roof panel. They also tested the impact resistance of untempered surface glass by the testing method in JIS3212. In this test, cracks could not be seen from a height of 75 cm.

  6. Flexible shaft and roof drilling system

    DOE Patents [OSTI]

    Blanz, John H.

    1981-01-01

    A system for drilling holes in the roof of a mine has a flexible shaft with a pair of oppositely wound, coaxial flat bands. One of the flat bands defines an inner spring that is wound right handed into a helical configuration, adjacent convolutions being in nesting relationship to one another. The other flat band defines an outer spring that is wound left handed into a helical configuration about the inner band, adjacent convolutions being nesting relationship with one another. A transition member that is configured to hold a rock bit is mounted to one end of the flexible shaft. When torque and thrust are applied to the flexible shaft by a driver, the inner spring expands outwardly and the outer spring contracts inwardly to form a relatively rigid shaft.

  7. Comparison of software models for energy savings from cool roofs

    SciTech Connect (OSTI)

    New, Joshua; Miller, William A.; Huang, Yu; Levinson, Ronnen

    2015-06-07

    For this study, a web-based Roof Savings Calculator (RSC) has been deployed for the United States Department of Energy as an industry-consensus tool to help building owners, manufacturers, distributors, contractors and researchers easily run complex roof and attic simulations. RSC simulates multiple roof and attic technologies for side-by-side comparison including reflective roofs, different roof slopes, above sheathing ventilation, radiant barriers, low-emittance roof surfaces, duct location, duct leakage rates, multiple substrate types, and insulation levels. Annual simulations of hour-by-hour, whole-building performance are used to provide estimated annual energy and cost savings from reduced HVAC use. While RSC reported similar cooling savings to other simulation engines, heating penalty varied significantly. RSC results show reduced cool roofing cost-effectiveness, thus mitigating expected economic incentives for this countermeasure to the urban heat island effect. This paper consolidates comparison of RSC's projected energy savings to other simulation engines including DOE-2.1E, AtticSim, Micropas, and EnergyPlus. Also included are comparisons to previous simulation-based studies, analysis of RSC cooling savings and heating penalties, the role of radiative heat exchange in an attic assembly, and changes made for increased accuracy of the duct model. Finally, radiant heat transfer and duct interaction not previously modeled is considered a major contributor to heating penalties.

  8. Comparison of software models for energy savings from cool roofs

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

    New, Joshua; Miller, William A.; Huang, Yu; Levinson, Ronnen

    2015-06-07

    For this study, a web-based Roof Savings Calculator (RSC) has been deployed for the United States Department of Energy as an industry-consensus tool to help building owners, manufacturers, distributors, contractors and researchers easily run complex roof and attic simulations. RSC simulates multiple roof and attic technologies for side-by-side comparison including reflective roofs, different roof slopes, above sheathing ventilation, radiant barriers, low-emittance roof surfaces, duct location, duct leakage rates, multiple substrate types, and insulation levels. Annual simulations of hour-by-hour, whole-building performance are used to provide estimated annual energy and cost savings from reduced HVAC use. While RSC reported similar cooling savingsmore » to other simulation engines, heating penalty varied significantly. RSC results show reduced cool roofing cost-effectiveness, thus mitigating expected economic incentives for this countermeasure to the urban heat island effect. This paper consolidates comparison of RSC's projected energy savings to other simulation engines including DOE-2.1E, AtticSim, Micropas, and EnergyPlus. Also included are comparisons to previous simulation-based studies, analysis of RSC cooling savings and heating penalties, the role of radiative heat exchange in an attic assembly, and changes made for increased accuracy of the duct model. Finally, radiant heat transfer and duct interaction not previously modeled is considered a major contributor to heating penalties.« less

  9. Cool Roofs: Your Questions Answered | Department of Energy

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

    Roofs: Your Questions Answered Cool Roofs: Your Questions Answered January 6, 2011 - 2:58pm Addthis John Schueler John Schueler Former New Media Specialist, Office of Public Affairs Last month Secretary Chu announced that the Department of Energy had installed a "cool roof" atop the west building of our Washington, DC headquarters. The announcement elicited a fair number of questions from his Facebook fans, so we decided to reach out to the people behind the project for their insight

  10. Energy Saving Melting and Revert Reduction Technology: Melting...

    Office of Scientific and Technical Information (OSTI)

    Consequently, die casters need to make careful choices in selecting and operating melting equipment and procedures. The capital cost of new melting equipment with higher efficiency ...

  11. Weathering of Roofing Materials-An Overview (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    Weathering of Roofing Materials-An Overview Citation Details In-Document ... Publication Date: 2006-03-30 OSTI Identifier: 929480 Report Number(s): LBNL--59724 Journal ID: CBUMEZ; ...

  12. Repairing Roofs and Ceilings: How To's for the Handy Homeowner

    SciTech Connect (OSTI)

    2006-01-01

    This brochure provides handy homeowners with tips on how to properly repair roofs and ceilings in their homes that sustained damage during a hurricane. This publications is a part of the How To's for the Handy Homeowner Series.

  13. Energy Saving "Cool Roofs" Installed at Y-12 | National Nuclear...

    National Nuclear Security Administration (NNSA)

    Energy Saving "Cool Roofs" Installed at Y-12 October 17, 2012 The Y-12 National Security Complex has taken additional steps to reduce its energy costs by installing almost 100,000 ...

  14. Geodesic-dome tank roof cuts water contamination, vapor losses

    SciTech Connect (OSTI)

    Barrett, A.E. )

    1989-07-10

    Colonial Pipeline Co. has established an ongoing program for using geodesic-dome roofs on tanks in liquid petroleum-product service. As its standard, Colonial adopted geodesicodone roofs, in conjunction with internal floating decks, to replace worn external floating roofs on existing tanks used in gasoline service and for use on new tanks in all types of product service. Geodesic domes are clear-span structures requiring no internal-support columns. This feature allows the associated use of a floating deck that is as vapor tight as is possible to construct. Further, geodesic domes can practically eliminate rainwater contamination, eliminate wind-generated vapor losses, and greatly reduce filling losses associated with conventional external floating roofs.

  15. Building America Case Study: Field Testing an Unvented Roof with...

    Energy Savers [EERE]

    ... Analysis of the data using ASHRAE Standard 160 and other mold growth criteria showed that the roofs remained suffciently wet into the spring (warmer weather) to run the risk of ...

  16. Energy Department Completes Cool Roof Installation on DC Headquarters...

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

    replacement project and it will save taxpayers 2,000 every year in building energy costs. ... As a result of the new cool roof installations on both buildings, taxpayers will save a ...

  17. Secretary Chu Announces Steps to Implement Cool Roofs at DOE...

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

    395 Kb . Cool roofs are one of the quickest and lowest cost ways we can reduce our global carbon emissions and begin the hard work of slowing climate change, said Secretary...

  18. Improved MK42 Melting Model

    SciTech Connect (OSTI)

    Tudor, A.A.

    2001-09-19

    An improved Mark 42 melting model has been defined for establishing confinement protection limits (CPLs). This report describes the new melting model and its application in computing CPLs.

  19. Urban Heat Islands: Cool Roof Infrastructure | Department of Energy

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

    Cool Roof Infrastructure Urban Heat Islands: Cool Roof Infrastructure Lead Performer: Lawrence Berkeley National Laboratory - U.S.-China Clean Energy Research Center Project Partners: -- Guangdong Provincial Academy of Building Research - Guangdong, China -- Chongqing University - Chongqing, China -- Research Institute of Standards and Norms - China -- Chinese Academy of Sciences - Beijing, China DOE Funding: $795,000 Project Term: Jan. 2011 - Dec. 2015 Project Objective The U.S.-China Clean

  20. ARM - Measurement - Ice nuclei

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

    : Ice nuclei Small particles around which ice particles form. Categories Cloud Properties Instruments The above measurement is considered scientifically relevant for the...

  1. Method and apparatus for anchoring roof bolts

    SciTech Connect (OSTI)

    Hipkins, E.C.; Locotos, F.M.; Comfort, J.D.

    1987-04-07

    This patent describes an anchor bolt assembly of the type used in mine roofs and the like in which the anchor bolt assembly is positioned in a bore hole of a rock formation. The bolt assembly includes an elongated bolt shaft with a head on one end and threads on the other end, and with a mechanical expansion anchor including a spreader on the threaded end. A quick-setting resin cartridge is positioned in the bore hole above the threaded end of the bolt shaft. The anchor bolt assembly is secured to the rock formation by both the expansion anchor and the quick-setting resin. The improvement described here comprises a stop connected to the bolt shaft immediately below the expansion anchor and an elongated helical coil having an upper end attached to the stop and positioned external of and surrounding a substantial length along the bolt shaft. The coil has a direction of coil so as to urge resin upwardly toward the threaded end while the spreader moves downwardly and while the bolt shaft is rotated in one continuous direction to achieve mixing of the resin and to secure the mechanical anchor to the rock formation.

  2. Inclusion of cool roofs in nonresidential Title 24 prescriptive requirements

    SciTech Connect (OSTI)

    Levinson, Ronnen; Akbari, Hashem; Konopacki, Steve; Bretz, Sarah

    2002-12-15

    Roofs that have high solar reflectance (high ability to reflect sunlight) and high thermal emittance (high ability to radiate heat) tend to stay cool in the sun. The same is true of low-emittance roofs with exceptionally high solar reflectance. Substituting a cool roof for a noncool roof tends to decrease cooling electricity use, cooling power demand, and cooling-equipment capacity requirements, while slightly increasing heating energy consumption. Cool roofs can also lower the ambient air temperature in summer, slowing ozone formation and increasing human comfort. DOE-2.1E building energy simulations indicate that use of a cool roofing material on a prototypical California nonresidential building with a low-sloped roof yields average annual cooling energy savings of approximately 300 kWh/1000 ft2 [3.2 kWh/m2], average annual natural gas deficits of 4.9 therm/1000 ft2 [5.6 MJ/m2], average source energy savings of 2.6 MBTU/1000 ft2 [30 MJ/m2], and average peak power demand savings of 0. 19 kW/1000 ft2 [2.1 W/m2]. The 15-year net present value (NPV) of energy savings averages $450/1000 ft2 [$4.90/m2] with time dependent valuation (TDV), and $370/1000 ft2 [$4.00/m2] without TDV. When cost savings from downsizing cooling equipment are included, the average total savings (15-year NPV + equipment savings) rises to $550/1000 ft2 [$5.90/m2] with TDV, and to $470/1000 ft2 [$5.00/m2] without TDV. Total savings range from 0.18 to 0.77 $/ft2 [1.90 to 8.30 $/m2] with TDV, and from 0.16 to 0.66 $/ft2 [1.70 to 7.10 $/m2] without TDV, across California's 16 climate zones. The typical cost premium for a cool roof is 0.00 to 0.20 $/ft2 [0.00 to 2.20 $/m2]. Cool roofs with premiums up to $0.20/ft2 [$2.20/m2] are expected to be cost effective in climate zones 2 through 16; those with premiums not exceeding $0.18/ft2 [$1.90/m2] are expected to be also cost effective in climate zone 1. Hence, this study recommends that the year-2005 California building energy efficiency code (Title 24

  3. Comparison of Software Models for Energy Savings from Cool Roofs

    SciTech Connect (OSTI)

    New, Joshua Ryan; Miller, William A; Huang, Yu; Levinson, Ronnen

    2014-01-01

    A web-based Roof Savings Calculator (RSC) has been deployed for the United States Department of Energy as an industry-consensus tool to help building owners, manufacturers, distributors, contractors and researchers easily run complex roof and attic simulations. This tool employs modern web technologies, usability design, and national average defaults as an interface to annual simulations of hour-by-hour, whole-building performance using the world-class simulation tools DOE-2.1E and AtticSim in order to provide estimated annual energy and cost savings. In addition to cool reflective roofs, RSC simulates multiple roof and attic configurations including different roof slopes, above sheathing ventilation, radiant barriers, low-emittance roof surfaces, duct location, duct leakage rates, multiple substrate types, and insulation levels. A base case and energy-efficient alternative can be compared side-by-side to estimate monthly energy. RSC was benchmarked against field data from demonstration homes in Ft. Irwin, California; while cooling savings were similar, heating penalty varied significantly across different simulation engines. RSC results reduce cool roofing cost-effectiveness thus mitigating expected economic incentives for this countermeasure to the urban heat island effect. This paper consolidates comparison of RSC s projected energy savings to other simulation engines including DOE-2.1E, AtticSim, Micropas, and EnergyPlus, and presents preliminary analyses. RSC s algorithms for capturing radiant heat transfer and duct interaction in the attic assembly are considered major contributing factors to increased cooling savings and heating penalties. Comparison to previous simulation-based studies, analysis on the force multiplier of RSC cooling savings and heating penalties, the role of radiative heat exchange in an attic assembly, and changes made for increased accuracy of the duct model are included.

  4. Rapid ice-wedge melting accelerates permafrost decline

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

    the DOE Next Generation Ecosystem Experiment, NGEE-Arctic, field site near Barrow, Alaska. ... the DOE Next Generation Ecosystem Experiment, NGEE-Arctic, field site near Barrow, Alaska. ...

  5. Rapid ice-wedge melting accelerates permafrost decline

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

    ... ponds result in more methane, but more drained land results in more carbon dioxide." ... unusually warm summer was enough to cause over 10 centimeters of surface subsidence. ...

  6. ARM - Lesson Plans: When Floating Ice Melts in the Sea

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

    Barrow, Alaska Tropical Western Pacific Site Tours Contacts Students Study Hall About ARM Global Warming FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox ...

  7. Empirically Derived Strength of Residential Roof Structures for Solar Installations.

    SciTech Connect (OSTI)

    Dwyer, Stephen F.; Sanchez, Alfred; Campos, Ivan A.; Gerstle, Walter H.

    2014-12-01

    Engineering certification for the installation of solar photovoltaic (PV) modules on wood roofs is often denied because existing wood roofs do not meet structural design codes. This work is intended to show that many roofs are actually sufficiently strong given the conservatism in codes, documented allowable strengths, roof structure system effects, and beam composite action produced by joist-sheathing interaction. This report provides results from a testing program to provide actual load carrying capacity of residential rooftops. The results reveal that the actual load carrying capacity of structural members and systems tested are significantly stronger than allowable loads provided by the International Residential Code (IRC 2009) and the national structural code found in Minimum Design Loads for Buildings and Other Structures (ASCE 7-10). Engineering analysis of residential rooftops typically ignores the system affects and beam composite action in determining rooftop stresses given a potential PV installation. This extreme conservatism combined with conservatism in codes and published allowable stress values for roof building materials (NDS 2012) lead to the perception that well built homes may not have adequate load bearing capacity to enable a rooftop PV installation. However, based on the test results presented in this report of residential rooftop structural systems, the actual load bearing capacity is several times higher than published values (NDS 2012).

  8. Community Ice Sheet Model (CISM2) Development and Marine Ice...

    Office of Scientific and Technical Information (OSTI)

    Community Ice Sheet Model (CISM2) Development and Marine Ice Sheet Simulations Citation Details In-Document Search Title: Community Ice Sheet Model (CISM2) Development and Marine ...

  9. Arctic ice islands

    SciTech Connect (OSTI)

    Sackinger, W.M.; Jeffries, M.O.; Lu, M.C.; Li, F.C.

    1988-01-01

    The development of offshore oil and gas resources in the Arctic waters of Alaska requires offshore structures which successfully resist the lateral forces due to moving, drifting ice. Ice islands are floating, a tabular icebergs, up to 60 meters thick, of solid ice throughout their thickness. The ice islands are thus regarded as the strongest ice features in the Arctic; fixed offshore structures which can directly withstand the impact of ice islands are possible but in some locations may be so expensive as to make oilfield development uneconomic. The resolution of the ice island problem requires two research steps: (1) calculation of the probability of interaction between an ice island and an offshore structure in a given region; and (2) if the probability if sufficiently large, then the study of possible interactions between ice island and structure, to discover mitigative measures to deal with the moving ice island. The ice island research conducted during the 1983-1988 interval, which is summarized in this report, was concerned with the first step. Monte Carlo simulations of ice island generation and movement suggest that ice island lifetimes range from 0 to 70 years, and that 85% of the lifetimes are less then 35 years. The simulation shows a mean value of 18 ice islands present at any time in the Arctic Ocean, with a 90% probability of less than 30 ice islands. At this time, approximately 34 ice islands are known, from observations, to exist in the Arctic Ocean, not including the 10-meter thick class of ice islands. Return interval plots from the simulation show that coastal zones of the Beaufort and Chukchi Seas, already leased for oil development, have ice island recurrences of 10 to 100 years. This implies that the ice island hazard must be considered thoroughly, and appropriate safety measures adopted, when offshore oil production plans are formulated for the Alaskan Arctic offshore. 132 refs., 161 figs., 17 tabs.

  10. Solare Cell Roof Tile And Method Of Forming Same

    DOE Patents [OSTI]

    Hanoka, Jack I. (Brookline, MA); Real, Markus (Oberberg, CH)

    1999-11-16

    A solar cell roof tile includes a front support layer, a transparent encapsulant layer, a plurality of interconnected solar cells and a backskin layer. The front support layer is formed of light transmitting material and has first and second surfaces. The transparent encapsulant layer is disposed adjacent the second surface of the front support layer. The interconnected solar cells has a first surface disposed adjacent the transparent encapsulant layer. The backskin layer has a first surface disposed adjacent a second surface of the interconnected solar cells, wherein a portion of the backskin layer wraps around and contacts the first surface of the front support layer to form the border region. A portion of the border region has an extended width. The solar cell roof tile may have stand-offs disposed on the extended width border region for providing vertical spacing with respect to an adjacent solar cell roof tile.

  11. Cool Roofs Through Time and Space (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Conference: Cool Roofs Through Time and Space Citation Details In-Document Search Title: Cool Roofs Through Time and Space You are accessing a document from the Department of ...

  12. Thermal performance of a Concrete Cool Roof under different climatic conditions of Mexico

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

    Hernández-Pérez, I.; Álvarez, G.; Gilbert, H.; Xamán, J.; Chávez, Y.; Shah, B.

    2014-11-27

    A cool roof is an ordinary roof with a reflective coating on the exterior surface which has a high solar reflectance and high thermal emittance. These properties let the roof keep a lower temperature than a standard roof under the same conditions. In this work, the thermal performance of a concrete roof with and without insulation and with two colors has been analyzed using the finite volume method. The boundary conditions of the external roof surface were taken from hourly averaged climatic data of four cities. For the internal surface, it is considered that the building is air-conditioned and themore » inside air has a constant temperature. The interior surface temperature and the heat flux rates into the roofs were obtained for two consecutive days in order to assess the benefits of a cool roofs in different climates.« less

  13. Field Testing Unvented Roofs with Asphalt Shingles in Cold and Hot-Humid Climates

    SciTech Connect (OSTI)

    Ueno, Kohta; Lstiburek, Joseph W.

    2015-09-01

    Test houses with unvented roof assemblies were built to measure long-term moisture performance, in the Chicago area (5A) and the Houston area (2A). The Chicago-area test bed had seven experimental rafter bays, including a control vented compact roof, and six unvented roof variants with cellulose or fiberglass insulation. The interior was run at 50% RH. The Houston-area roof was an unvented attic insulated with spray-applied fiberglass. Most ridges and hips were built with a diffusion vent detail, capped with vapor permeable roof membrane. In contrast, the diffusion vent roofs had drier conditions at the roof peak in wintertime, but during the summer, RHs and MCs were higher than the unvented roof (albeit in the safe range).

  14. Sustainable Retrofit of Residential Roofs Using Metal Roofing Panels, Thin-Film Photovoltaic Laminates, and PCM Heat Sink Technology

    SciTech Connect (OSTI)

    Kosny, Jan; Miller, William A; Childs, Phillip W; Biswas, Kaushik

    2011-01-01

    During September-October 2009, research teams representing Metal Construction Association (the largest North American trade association representing metal building manufacturers, builders, and material suppliers), CertainTeed (one of the largest U.S. manufacturers of thermal insulation and building envelope materials), Unisolar (largest U.S. producer of amorphous silicone photo-voltaic (PV) laminates), Phase Change Energy (manufacturer of bio-based PCM), and Oak Ridge National Laboratory (ORNL) installed three experimental attics utilizing different roof retrofit strategies in the ORNL campus. The main goal of this project was experimental evaluation of a newly-developed sustainable re-roofing technology utilizing amorphous silicone PV laminates integrated with metal roof and PCM heat sink. The experimental attic with PV laminate was expected to work during the winter time as a passive solar collector with PCM storing solar heat, absorbed during the day, and increasing overall attic air temperature during the night.

  15. New Cool Roof Coatings and Affordable Cool Color Asphalt | Department of

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

    Energy New Cool Roof Coatings and Affordable Cool Color Asphalt New Cool Roof Coatings and Affordable Cool Color Asphalt Emerging Technologies Project for the 2013 Building Technologies Office's Program Peer Review emrgtech25_cheng_040413.pdf (1.35 MB) More Documents & Publications Accelerated Aging of Roofing Materials - 2013 BTO Peer Review Berkeley Lab Heat Island Group research assistant Sharon Chen prepares a prototype of high-performance cool shingle roofing. Credit: Heat Island

  16. Load test of the 272W Building high bay roof deck and support structure

    SciTech Connect (OSTI)

    McCoy, R.M.

    1994-09-28

    This reports the results of the Load Test of the 272W Building High Bay Roof Deck and Support Structure.

  17. Inclusion of cool roofs in nonresidential Title 24 prescriptiverequirements

    SciTech Connect (OSTI)

    Levinson, Ronnen; Akbari, Hashem; Konopacki, Steve; Bretz, Sarah

    2003-07-01

    Roofs that have high solar reflectance (high ability toreflect sunlight) and high thermal emittance (high ability to radiateheat) tend to stay cool in the sun. The same is true of low-emittanceroofs with exceptionally high solar reflectance. Substituting a cool rooffor a non-cool roof tends to decrease cooling electricity use, coolingpower demand, and cooling-equipment capacity requirements, while slightlyincreasing heating energy consumption. Cool roofs can also lower citywideambient air temperature in summer, slowing ozone formation and increasinghuman comfort.DOE-2.1E building energy simulations indicate that use of acool roofing material on a prototypical California nonresidential (NR)building with a low-sloped roof yields average annual cooling energysavings of approximately 3.2 kW h/m2 (300 kW h/1000 ft2), average annualnatural gas deficits of 5.6 MJ/m2 (4.9 therm/1000 ft2), average annualsource energy savings of 30 MJ/m2 (2.6 MBTU/1000 ft2), and average peakpower demand savings of 2.1 W/m2 (0.19 kW/1000 ft2). The 15-year netpresent value (NPV) of energy savings averages $4.90/m2 ($450/1000 ft2)with time-dependent valuation (TDV), and $4.00/m2 ($370/1000 ft2) withoutTDV. When cost savings from downsizing cooling equipment are included,the average total savings (15-year NPV+equipment savings) rises to$5.90/m2 ($550/1000 ft2) with TDV, and to $5.00/m2 ($470/1000 ft2)without TDV.Total savings range from 1.90 to 8.30 $/m2 (0.18 0.77 $/ft2)with TDV, and from 1.70 to 7.10 $/m2 (0.16 0.66 $/ft2) without TDV,across California's 16 climate zones. The typical cost premium for a coolroof is 0.00 2.20 $/m2 (0.00 0.20 $/ft2). Cool roofs with premiums up to$2.20/m2 ($0.20/ft2) are expected to be cost effective in climate zones 216; those with premiums not exceeding $1.90/m2 ($0.18/ft2) are expectedto be also cost effective in climate zone 1. Hence, this study recommendsthat the year-2005 California building energy efficiency code (Title 24,Part 6 of the California Code of

  18. Field Testing Unvented Roofs with Asphalt Shingles in Cold and Hot-Humid Climates

    SciTech Connect (OSTI)

    Ueno, Kohta; Lstiburek, Joseph W.

    2015-09-01

    Insulating roofs with dense-pack cellulose (instead of spray foam) has moisture risks, but is a lower cost approach. If moisture risks could be addressed, buildings could benefit from retrofit options, and the ability to bring HVAC systems within the conditioned space. Test houses with unvented roof assemblies were built to measure long-term moisture performance, in the Chicago area (5A) and the Houston area (2A). The Chicago-area test bed had seven experimental rafter bays, including a control vented compact roof, and six unvented roof variants with cellulose or fiberglass insulation. The interior was run at 50% RH. All roofs except the vented cathedral assembly experienced wood moisture contents and RH levels high enough to constitute failure. Disassembly at the end of the experiment showed that the unvented fiberglass roofs had wet sheathing and mold growth. In contrast, the cellulose roofs only had slight issues, such as rusted fasteners and sheathing grain raise. The Houston-area roof was an unvented attic insulated with spray-applied fiberglass. Most ridges and hips were built with a diffusion vent detail, capped with vapor permeable roof membrane. Some ridge sections were built as a conventional unvented roof, as a control. In the control unvented roofs, roof peak RHs reached high levels in the first winter; as exterior conditions warmed, RHs quickly fell. In contrast, the diffusion vent roofs had drier conditions at the roof peak in wintertime, but during the summer, RHs and MCs were higher than the unvented roof (albeit in the safe range).

  19. OSTIblog Articles in the cool roof Topic | OSTI, US Dept of Energy Office

    Office of Scientific and Technical Information (OSTI)

    of Scientific and Technical Information cool roof Topic OSTI's Cool Roof by Dr. Jeffrey Salmon 10 Nov, 2010 in Technology 2629 CIMG3811.JPG OSTI's Cool Roof Read more about 2629 The Office of Science occupies many buildings around the country, but it owns only two of them. One of them is making some news. The 134,629 sq. ft. (about 3 acres) roof of the Office of Scientific and Technical Information (OSTI) building in Oak Ridge, Tennessee is now officially a Cool Roof, that is, it's energy

  20. Changes in the firn structure of the western Greenland Ice Sheet caused by recent warming

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

    de la Peña, S.; Howat, I. M.; Nienow, P. W.; van den Broeke, M. R.; Mosley-Thompson, E.; Price, S. F.; Mair, D.; Noël, B.; Sole, A. J.

    2015-06-11

    Atmospheric warming over the Greenland Ice Sheet during the last 2 decades has increased the amount of surface meltwater production, resulting in the migration of melt and percolation regimes to higher altitudes and an increase in the amount of ice content from refrozen meltwater found in the firn above the superimposed ice zone. Here we present field and airborne radar observations of buried ice layers within the near-surface (0–20 m) firn in western Greenland, obtained from campaigns between 1998 and 2014. We find a sharp increase in firn-ice content in the form of thick widespread layers in the percolation zone,more » which decreases the capacity of the firn to store meltwater. The estimated total annual ice content retained in the near-surface firn in areas with positive surface mass balance west of the ice divide in Greenland reached a maximum of 74 ± 25 Gt in 2012, compared to the 1958–1999 average of 13 ± 2 Gt, while the percolation zone area more than doubled between 2003 and 2012. Increased melt and column densification resulted in surface lowering averaging –0.80 ± 0.39 m yr⁻¹ between 1800 and 2800 m in the accumulation zone of western Greenland. Since 2007, modeled annual melt and refreezing rates in the percolation zone at elevations below 2100 m surpass the annual snowfall from the previous year, implying that mass gain in the region is retained after melt in the form of refrozen meltwater. If current melt trends over high elevation regions continue, subsequent changes in firn structure will have implications for the hydrology of the ice sheet and related abrupt seasonal densification could become increasingly significant for altimetry-derived ice sheet mass balance estimates.« less

  1. EVALUATION OF ROOF BOLTING REQUIREMENTS BASED ON IN-MINE BOLTER DRILLING

    SciTech Connect (OSTI)

    Syd S. Peng

    2002-07-15

    Roof bolting is the most popular method for underground openings in the mining industry, especially in the bedded deposits such as coal, potash, salt etc. In fact, all U.S. underground coal mine entries are roof-bolted as required by law. However, roof falls still occur frequently in the roof bolted entries. The two possible reasons are: the lack of knowledge of and technology to detect the roof geological conditions in advance of mining, and lack of roof bolting design criteria for modern roof bolting systems. This research is to develop a method for predicting the roof geology and stability condition in real time during roof bolting operation. Based on such information, roof bolting design criteria for modern roof bolting systems will be developed for implementation in real time. Field tests have been performed in two underground coal mines in this quarter. It also found from the tests that the non-drilling thrust and torque should be deducted from the acquired drilling data. The non-drilling torque is actually higher than that is used to overcome the shear strength is proportional to the rotation rate.

  2. Load test of the 277W Building high bay roof deck and support structure

    SciTech Connect (OSTI)

    McCoy, R.M.

    1994-12-02

    The 277W Building high bay roof area was load tested according to the approved load-test procedure, WHC-SD-GN-TP-30015, Revision 1. The 277W Building is located in the 200 West Area of the Hanford Site and has the following characteristics: roof deck -- wood decking supported by 4 x 14 timber purlins; roof membrane -- tar and gravel; roof slope -- flat (<10 deg); and roof elevation -- maximum height of about 63 ft. The 227W Building was visited in March 1994 for a visual inspection. During this inspection, cracked areas were visible in the decking, but it was not possible to determine whether these cracks extended completely through the decking, which is 2-in. thick. The building was revisited in March 1994 for the purpose of writing this test report. Because the roof requires personnel access, a test was determined to be the best way to qualify the roof. The conclusions are that the roof has been qualified for 500-lb total roof load and that the ``No Roof Access`` signs can be changed to ``Roof Access Restricted`` signs.

  3. Load test of the 3701U Building roof deck and support structure

    SciTech Connect (OSTI)

    McCoy, R.M.

    1994-09-14

    The 3701U Building roof area was load tested according to the approved load-test procedure. The 3701U Building is located in the 300 Area of the Hanford Site and has the following characteristics: Roof deck--metal decking supported by steel purlins; Roof membrane--tar and gravel; Roof slope--flat (<10 deg); and Roof elevation--height of about 12.5 ft. The 3701U Building was visited in August 1992 for a visual inspection, but because of insulation an inspection could not be performed. The building was revisited in March 1994 for the purpose of writing this test report. Because the roof could not be inspected, a test was determined to be the best way to qualify the roof for personnel access. The test procedure called for the use of a remotely-controlled robot. The conclusions are that the roof has been qualified for 500-lb total roof load and that the ``No Roof Access`` signs can be changed to ``Roof Access Restricted`` signs.

  4. Structural testing of corrugated asbestos-cement roof panels at the Hanford Facilities, Richland, Washington

    SciTech Connect (OSTI)

    Moustafa, S.E.; Rodehaver, S.M.; Frier, W.A.

    1993-10-01

    This report describes a roof testing program that was carried out at the 105KE/KW Spent Fuel Storage Basins and their surrounding facilities at the Hanford Site in Richland, Washington. The roof panels were constructed in the mid 1950`s of corrugated asbestos-cement (A/C), which showed common signs of aging. Based on the construction specifications, the panels capacity to meet current design standards was questioned. Both laboratory and in-situ load testing of the corrugated A/C panels was conducted. The objective of the complete test program was to determine the structural integrity of the existing A/C roof panels installed in the 105KE and 105KW facilities. The data from these tests indicated that the roofs are capable of resisting the design loads and are considered safe. A second phase test to address the roof resistance to personnel and roof removal/roofing system installation equipment was recommended and is underway.

  5. The Equivalent Thermal Resistance of Tile Roofs with and without Batten Systems

    SciTech Connect (OSTI)

    Miller, William A

    2013-01-01

    Clay and concrete tile roofs were installed on a fully instrumented attic test facility operating in East Tennessee s climate. Roof, attic and deck temperatures and heat flows were recorded for each of the tile roofs and also on an adjacent attic cavity covered with a conventionally pigmented and direct-nailed asphalt shingle roof. The data were used to benchmark a computer tool for simulation of roofs and attics and the tool used to develop an approach for computing an equivalent seasonal R-value for sub-tile venting. The approach computed equal heat fluxes through the ceilings of roofs having different combinations of surface radiation properties and or building constructions. A direct nailed shingle roof served as a control for estimating the equivalent thermal resistance of the air space. Simulations were benchmarked to data in the ASHRAE Fundamentals for the thermal resistance of inclined and closed air spaces.

  6. Load test of the 283W Clearwell Roof Deck and Support Structure

    SciTech Connect (OSTI)

    McCoy, R.M.

    1994-09-12

    The 283W Clearwell roof area was load tested according to the approved load-test procedure, WHC-SD-GN-TP-30015, Revision 0, as modified below. The 283W Clearwell is located in the 200 West Area of the Hanford Site and has the following characteristics: Roof deck - concrete slab supported by columns and walls; Roof membrane - tar and gravel; Roof slope - flat (< 10 deg); and Roof elevation - approximately 6 in. above ground level. The 283W Clearwell was visited in April 1993 for a visual inspection, but could not be inspected because of the confined space requirements. It was revisited in February 1994 for the purpose of writing this test report. Because the roof could not be inspected, a test was determined to be the best way to qualify the roof for personnel access.

  7. Arctic sea ice modeling with the material-point method.

    SciTech Connect (OSTI)

    Peterson, Kara J.; Bochev, Pavel Blagoveston

    2010-04-01

    Arctic sea ice plays an important role in global climate by reflecting solar radiation and insulating the ocean from the atmosphere. Due to feedback effects, the Arctic sea ice cover is changing rapidly. To accurately model this change, high-resolution calculations must incorporate: (1) annual cycle of growth and melt due to radiative forcing; (2) mechanical deformation due to surface winds, ocean currents and Coriolis forces; and (3) localized effects of leads and ridges. We have demonstrated a new mathematical algorithm for solving the sea ice governing equations using the material-point method with an elastic-decohesive constitutive model. An initial comparison with the LANL CICE code indicates that the ice edge is sharper using Materials-Point Method (MPM), but that many of the overall features are similar.

  8. Isothermal Melting | Department of Energy

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

    New Energy-Efficient Melting Process Saves Energy and Reduces Production Losses Aluminum ... thermal, and mechanical robustness required in an industrial molten aluminum environment. ...

  9. A user`s perspective on aluminum dome roofs for aboveground tanks

    SciTech Connect (OSTI)

    Myers, P.E.

    1995-12-31

    There is a trend in the petroleum industry to install aluminum dome roofs on storage tanks of all kinds. Although most dome roofs have been installed on floating roof tanks, there is a trend to install them on fixed roof tanks as well, substituting the familiar shallow fixed cone roof with a geodesic dome. In part, this trend has been caused by EPA requirements causing a greater number of closed tanks to be vented to vapor recovery or vapor destruction systems. Both the aluminum roof manufacturing community and the user have moved into a whole new set of problems associated with the change in dome roof applications from atmospheric to those requiring internal pressure. New problems are just now being dealt with and solved because cost factors tend to make the aluminum dome an economic solution for many cases where sealed tank systems must be used. Because of the increased numbers of geodesic domes as either an alternative to a fixed cone roof tank or as a way to convert an external floating roof tank to an internal floating roof tank or as their potential to serve as tools in the environmental arena, it is the intent of this paper to examine them from the user`s perspective. In addition, some areas of research that should resolve some reliability and safety issues are presented for consideration and research by not only manufacturers but the users as well.

  10. A Study of the Energy-Saving Potential of Metal Roofs Incorporating Dynamic Insulation Systems

    SciTech Connect (OSTI)

    Biswas, Kaushik; Miller, William A; Kriner, Scott; Manlove, Gary

    2013-01-01

    This article presents various metal roof configurations that were tested at Oak Ridge National Laboratory in Tennessee, U.S. between 2009 and 2013, and describes their potential for reducing the attic-generated space-conditioning loads. These roofs contained different combinations of phase-change material, rigid insulation, low emittance surface, and above-sheathing ventilation with standing-seam metal panels on top. These roofs were designed to be installed on existing roofs decks, or on top of asphalt shingles for retrofit construction. All the tested roofs showed the potential for substantial energy savings compared to an asphalt shingle roof, which was used as a control for comparison. The roofs were constructed on a series of adjacent attics separated at the gables using thick foam insulation. The attics were built on top of a conditioned room. All attics were vented at the soffit and ridge. The test roofs and attics were instrumented with an array of thermocouples. Heat flux transducers were installed in the roof deck and attic floor (ceiling) to measure the heat flows through the roof and between the attic and conditioned space below. Temperature and heat flux data were collected during the heating, cooling and swing seasons over a three-year period. Data from previous years of testing have been published. Here, data from the latest roof configurations being tested in year three of the project are presented. All test roofs were highly effective in reducing the heat flows through the roof and ceiling, and in reducing the diurnal attic-temperature fluctuations.

  11. Building America Case Study: Field Testing an Unvented Roof with Fibrous Insulation and Tiles, Orlando, Florida

    SciTech Connect (OSTI)

    2015-11-01

    This research is a test implementation of an unvented tile roof assembly in a hot-humid climate (Orlando, FL; Zone 2A), insulated with air permeable insulation (netted and blown fiberglass). Given the localized moisture accumulation and failures seen in previous unvented roof field work, it was theorized that a 'diffusion vent' (water vapor open, but air barrier 'closed') at the highest points in the roof assembly might allow for the wintertime release of moisture, to safe levels. The 'diffusion vent' is an open slot at the ridge and hips, covered with a water-resistant but vapor open (500+ perm) air barrier membrane. As a control comparison, one portion of the roof was constructed as a typical unvented roof (self-adhered membrane at ridge). The data collected to date indicate that the diffusion vent roof shows greater moisture safety than the conventional, unvented roof design. The unvented roof had extended winter periods of 95-100% RH, and wafer (wood surrogate RH sensor) measurements indicating possible condensation; high moisture levels were concentrated at the roof ridge. In contrast, the diffusion vent roofs had drier conditions, with most peak MCs (sheathing) below 20%. In the spring, as outdoor temperatures warmed, all roofs dried well into the safe range (10% MC or less). Some roof-wall interfaces showed moderately high MCs; this might be due to moisture accumulation at the highest point in the lower attic, and/or shading of the roof by the adjacent second story. Monitoring will be continued at least through spring 2016 (another winter and spring).

  12. Innovative Ballasted Flat Roof Solar PV Racking System

    SciTech Connect (OSTI)

    Peek, Richard T.

    2015-01-23

    The objective of this project was to reduce the cost of racking for PV solar on flat commercial rooftops. Cost reductions would come from both labor savings and material savings related to the installation process. The rack would need to accommodate the majority of modules available on the market. Cascade Engineering has a long history of converting traditional metal type applications over to plastic. Injection molding of plastics have numerous advantages including selection of resin for the application, placing the material exactly where it is needed, designing in features that will speed up the installation process, and weight reduction of the array. A plastic rack would need to meet the requirements of UL2703, Mounting systems, mounting devices, clamping/retention devices, and ground lugs for use with flat-plate photovoltaic modules and panels. Comparing original data to the end of project racking design, racking material costs were reduced 50% and labor costs reduced 64%. The racking product accommodates all 60 and 72 cell panels on the market, meets UL2703 requirements, contributes only 1.3 pounds per square foot of weight to the array, requires little ballast to secure the array, automatically grounds the module when the module is secured, stacks/nests well for shipping/fewer lifts to the roof, provides integrated wire routing, allows water to drain on the roof, and accommodates various seismic roof connections. Project goals were achieved as noted in the original funding application.

  13. Mobile Ice Nucleus Spectrometer

    SciTech Connect (OSTI)

    Kulkarni, Gourihar R.; Kok, G. L.

    2012-05-07

    This first year report presents results from a computational fluid dynamics (CFD) study to assess the flow and temperature profiles within the mobile ice nucleus spectrometer.

  14. Technology Solutions Case Study: Field Testing an Unvented Roof with Asphalt Shingles in a Cold Climate

    SciTech Connect (OSTI)

    K. Ueno and J. Lstiburek

    2015-09-01

    Test houses with unvented roof assemblies were built to measure long-term moisture performance, in the Chicago area (5A) and the Houston area (2A). The Chicago-area test bed had seven experimental rafter bays, including a "control" vented compact roof, and six unvented roof variants with cellulose or fiberglass insulation. The interior was run at 50% RH. All roofs except the vented cathedral assembly experienced wood moisture contents and RH levels high enough to constitute failure. Disassembly at the end of the experiment showed that the unvented fiberglass roofs had wet sheathing and mold growth. In contrast, the cellulose roofs only had slight issues, such as rusted fasteners and sheathing grain raise.

  15. Global Simulations of Ice nucleation and Ice Supersaturation...

    Office of Scientific and Technical Information (OSTI)

    Community Atmosphere Model Citation Details In-Document Search Title: Global Simulations of Ice nucleation and Ice Supersaturation with an Improved Cloud Scheme in the Community ...

  16. Community Ice Sheet Model (CISM2) Development and Marine Ice...

    Office of Scientific and Technical Information (OSTI)

    Community Ice Sheet Model (CISM2) Development and Marine Ice Sheet Simulations Citation ... Sponsoring Org: DOELANL Country of Publication: United States Language: English Subject: ...

  17. Monitoring the Energy-Use Effects of Cool Roofs on California Commercial Buildings

    SciTech Connect (OSTI)

    Akbari, Hashem; Levinson, Ronnen; Konopaki, Steve; Rainer, Leo

    2004-07-01

    Solar-reflective roofs stay cooler in the sun than solar-absorptive roofs. Such ''cool'' roofs achieve lower surface temperatures that reduce heat conduction into the building and the building's cooling load. The California Energy Commission has funded research in which Lawrence Berkeley National Laboratory (LBNL) has measured the electricity use and peak demand in commercial buildings to document savings from implementing the Commission's Cool Roofs program. The study seeks to determine the savings achieved by cool roofs by monitoring the energy use of a carefully selected assortment of buildings participating in the Cool Roofs program. Measurements were needed because the peak savings resulting from the application of cool roofs on different types of buildings in the diverse California climate zones have not been well characterized to date. Only a few occupancy categories (e.g., office and retail buildings) have been monitored before this, and those were done under a limited number of climatic conditions. To help rectify this situation, LBNL was tasked to select the buildings to be monitored, measure roof performance before and after replacing a hot roof by a cool roof, and document both energy and peak demand savings resulting from installation of cool roofs. We monitored the effects of cool roofs on energy use and environmental parameters in six California buildings at three different sites: a retail store in Sacramento; an elementary school in San Marcos (near San Diego); and a 4-building cold storage facility in Reedley (near Fresno). The latter included a cold storage building, a conditioning and fruit-palletizing area, a conditioned packing area, and two unconditioned packing areas (counted as one building).

  18. CERC-BEE Cool Roofs and Urban Heat Islands: infrastructure and anti-soiling coatings

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

    Ronnen Levinson, Staff Scientist, LBNL RMLevinson@LBL.gov Scott Hunter, Senior Research Scientist, ORNL HunterSR@ORNL.gov CERC-BEE Cool Roofs and Urban Heat Islands: infrastructure and anti-soiling coatings 2014 Building Technologies Office Peer Review 2 Project Summary (Cool Roof Infrastructure) Timeline: Start date: January 2011 Planned end date: December 2015 Key Milestones 1. Initiate natural exposure trials in many Chinese cities for roof product rating (6/2014) 2. Start black/white/garden

  19. Secretary Chu Announces Steps to Implement Cool Roofs at DOE and Across the

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

    Federal Government | Department of Energy Steps to Implement Cool Roofs at DOE and Across the Federal Government Secretary Chu Announces Steps to Implement Cool Roofs at DOE and Across the Federal Government July 19, 2010 - 12:00am Addthis Washington - U.S. Department of Energy Secretary Steven Chu today announced a series of initiatives underway at the Department of Energy to more broadly implement cool roof technologies on DOE facilities and buildings across the federal government. Cool

  20. Field Evaluation of Four Novel Roof Designs for Energy-Efficient Manufactured Homes

    SciTech Connect (OSTI)

    Levy, E.; Dentz, J.; Ansanelli, E.; Barker, G.; Rath, P.; Dadia, D.

    2015-12-01

    A five-bay roof test structure was built, instrumented and monitored in an effort to determine through field testing and analysis the relative contributions of select technologies toward reducing energy use in new manufactured homes. The roof structure in Jamestown, California was designed to examine how differences in roof construction impact space conditioning loads, wood moisture content and attic humidity levels. Conclusions are drawn from the data on the relative energy and moisture performance of various configurations of vented and sealed attics.

  1. Energy Saving "Cool Roofs" Installed at Y-12 | National Nuclear

    National Nuclear Security Administration (NNSA)

    Security Administration | (NNSA) Energy Saving "Cool Roofs" Installed at Y-12 October 17, 2012 The Y-12 National Security Complex has taken additional steps to reduce its energy costs by installing almost 100,000 square feet of new heat reflective "cool" roofs at the Oak Ridge, Tennessee facility. File 2012-10-17 NPO Y-12 Cool Roofs.docx

  2. Measure Guideline. Deep Energy Enclosure Retrofit for Zero Energy Ready House Flat Roofs

    SciTech Connect (OSTI)

    Loomis, H.; Pettit, B.

    2015-05-29

    This Measure Guideline provides design and construction information for a deep energy enclosure retrofit solution of a flat roof assembly. It describes the strategies and procedures for an exterior retrofit of a flat wood-framed roof with brick masonry exterior walls using exterior and interior (framing cavity) insulation. The approach supported in this guide could also be adapted for use with flat wood-framed roofs with wood-framed exterior walls.

  3. Measure Guideline: Deep Energy Enclosure Retrofit for Zero Energy Ready House Flat Roofs

    SciTech Connect (OSTI)

    Loomis, H.; Pettit, B.

    2015-05-01

    This Measure Guideline provides design and construction information for a deep energy enclosure retrofit (DEER) solution of a flat roof assembly. It describes the strategies and procedures for an exterior retrofit of a flat, wood-framed roof with brick masonry exterior walls, using exterior and interior (framing cavity) insulation. The approach supported in this guide could also be adapted for use with flat, wood-framed roofs with wood-framed exterior walls.

  4. Application of Spray Foam Insulation Under Plywood and Oriented Strand Board Roof Sheathing

    SciTech Connect (OSTI)

    Grin, A. [Building Science Corporation, Somerville, MA (United States); Smegal, J. [Building Science Corporation, Somerville, MA (United States); Lstiburek, J. [Building Science Corporation, Somerville, MA (United States)

    2013-10-01

    Unvented roof strategies with open cell and closed cell spray polyurethane foam insulation sprayed to the underside of roof sheathing have been used since the mid-1990's to provide durable and efficient building enclosures. However, there have been isolated moisture related incidents reported anecdotally that raise potential concerns about the overall hygrothermal performance of these systems. This project involved hygrothermal modeling of a range of rainwater leakage and field evaluations of in-service residential roofs using spray foam insulation. All of the roof assemblies modeled exhibited drying capacity to handle minor rainwater leakage. All field evaluation locations of in-service residential roofs had moisture contents well within the safe range for wood-based sheathing. Explorations of eleven in-service roof systems were completed. The exploration involved taking a sample of spray foam from the underside of the roof sheathing, exposing the sheathing, then taking a moisture content reading. All locations had moisture contents well within the safe range for wood-based sheathing. One full-roof failure was reviewed, as an industry partner was involved with replacing structurally failed roof sheathing. In this case the manufacturer's investigation report concluded that the spray foam was installed on wet OSB based on the observation that the spray foam did not adhere well to the substrate and the pore structure of the closed cell spray foam at the ccSPF/OSB interface was indicative of a wet substrate.

  5. Performance Comparison of a BIPV Roofing Tile System in Two Mounting Configurations (Poster)

    SciTech Connect (OSTI)

    Muller, M.; Rodriquez, J.; Marion, B.

    2009-06-01

    This work examined the thermal and power characteristics of a building-integrated photovoltaic (BIPV) roofing system using two installation techniques, counter-batten and direct-mount.

  6. Performance Comparison of a BIPV Roofing Tile System in Two Mounting Configurations: Preprint

    SciTech Connect (OSTI)

    Muller, M. T.; Rodrigeuz, J.; Marion, B.

    2009-06-01

    This work examined the thermal and power characteristics of a building-integrated photovoltaic (BIPV) roofing system using two installation techniques, counter-batten and direct-mount.

  7. Asphalt Roofing Shingles Into Energy Project Summary Report

    SciTech Connect (OSTI)

    Jameson, Rex, PE

    2008-04-28

    Based on a widely cited September, 1999 report by the Vermont Agency of Natural Resources, nearly 11 million tons of asphalt roofing shingle wastes are produced in the United States each year. Recent data suggests that the total is made up of about 9.4 million tons from roofing tear-offs and about 1.6 million tons from manufacturing scrap. Developing beneficial uses for these materials would conserve natural resources, promote protection of the environment and strengthen the economy. This project explored the feasibility of using chipped asphalt shingle materials in cement manufacturing kilns and circulating fluidized bed (CFB) boilers. A method of enhancing the value of chipped shingle materials for use as fuel by removing certain fractions for use as substitute raw materials for the manufacture of new shingles was also explored. Procedures were developed to prevent asbestos containing materials from being processed at the chipping facilities, and the frequency of the occurrence of asbestos in residential roofing tear-off materials was evaluated. The economic feasibility of each potential use was evaluated based on experience gained during the project and on a review of the well established use of shingle materials in hot mix asphalt. This project demonstrated that chipped asphalt shingle materials can be suitable for use as fuel in circulating fluidized boilers and cement kilns. More experience would be necessary to determine the full benefits that could be derived and to discover long term effects, but no technical barriers to full scale commercial use of chipped asphalt shingle materials in these applications were discovered. While the technical feasibility of various options was demonstrated, only the use of asphalt shingle materials in hot mix asphalt applications is currently viable economically.

  8. Attic or Roof? An Evaluation of Two Advanced Weatherization Packages

    SciTech Connect (OSTI)

    Neuhauser, K.

    2012-06-01

    This project examines implementation of advanced retrofit measures in the context of a large-scale weatherization program and the archetypal Chicago brick bungalow. One strategy applies best practice air sealing methods and a standard insulation method to the attic floor. The other strategy creates an unvented roof assembly using materials and methods typically available to weatherization contractors. Through implementations of the retrofit strategies in a total of eight (8) test homes, the research found that the two different strategies achieve similar reductions in air leakage measurement (55%) and predicted energy performance (18%) relative to the pre-retrofit conditions.

  9. Seismic Evidence For A Hydrothermal Layer Above The Solid Roof...

    Open Energy Info (EERE)

    are formed by cooling and crystallization of melt in magma chambers. Authors S. C. Singh, J. S. Collier, A. J. Harding, G. M. Kent and J. A. Orcutt Published Journal Publisher Not...

  10. THE STRUCTURE OF SURFACE H{sub 2}O LAYERS OF ICE-COVERED PLANETS WITH HIGH-PRESSURE ICE

    SciTech Connect (OSTI)

    Ueta, S.; Sasaki, T. E-mail: takanori@geo.titech.ac.jp

    2013-10-01

    Many extrasolar (bound) terrestrial planets and free-floating (unbound) planets have been discovered. While the existence of bound and unbound terrestrial planets with liquid water is an important question, of particular importance is the question of these planets' habitability. Even for a globally ice-covered planet, geothermal heat from the planetary interior may melt the interior ice, creating an internal ocean covered by an ice shell. In this paper, we discuss the conditions that terrestrial planets must satisfy for such an internal ocean to exist on the timescale of planetary evolution. The question is addressed in terms of planetary mass, distance from a central star, water abundance, and abundance of radiogenic heat sources. In addition, we investigate the structure of the surface H{sub 2}O layers of ice-covered planets by considering the effects of ice under high pressure (high-pressure ice). As a fiducial case, a 1 M{sub ?} planet at 1 AU from its central star and with 0.6-25 times the H{sub 2}O mass of the Earth could have an internal ocean. We find that high-pressure ice layers may appear between the internal ocean and the rock portion on a planet with an H{sub 2}O mass over 25 times that of the Earth. The planetary mass and abundance of surface water strongly restrict the conditions under which an extrasolar terrestrial planet may have an internal ocean with no high-pressure ice under the ocean. Such high-pressure ice layers underlying the internal ocean are likely to affect the habitability of the planet.

  11. Arctic Sea ice model sensitivities.

    SciTech Connect (OSTI)

    Peterson, Kara J.; Bochev, Pavel Blagoveston; Paskaleva, Biliana Stefanova

    2010-12-01

    Arctic sea ice is an important component of the global climate system and, due to feedback effects, the Arctic ice cover is changing rapidly. Predictive mathematical models are of paramount importance for accurate estimates of the future ice trajectory. However, the sea ice components of Global Climate Models (GCMs) vary significantly in their prediction of the future state of Arctic sea ice and have generally underestimated the rate of decline in minimum sea ice extent seen over the past thirty years. One of the contributing factors to this variability is the sensitivity of the sea ice state to internal model parameters. A new sea ice model that holds some promise for improving sea ice predictions incorporates an anisotropic elastic-decohesive rheology and dynamics solved using the material-point method (MPM), which combines Lagrangian particles for advection with a background grid for gradient computations. We evaluate the variability of this MPM sea ice code and compare it with the Los Alamos National Laboratory CICE code for a single year simulation of the Arctic basin using consistent ocean and atmospheric forcing. Sensitivities of ice volume, ice area, ice extent, root mean square (RMS) ice speed, central Arctic ice thickness,and central Arctic ice speed with respect to ten different dynamic and thermodynamic parameters are evaluated both individually and in combination using the Design Analysis Kit for Optimization and Terascale Applications (DAKOTA). We find similar responses for the two codes and some interesting seasonal variability in the strength of the parameters on the solution.

  12. CAVERN ROOF STABILITY FOR NATURAL GAS STORAGE IN BEDDED SALT

    SciTech Connect (OSTI)

    DeVries, Kerry L; Mellegard, Kirby D; Callahan, Gary D; Goodman, William M

    2005-06-01

    This report documents research performed to develop a new stress-based criterion for predicting the onset of damage in salt formations surrounding natural gas storage caverns. Laboratory tests were conducted to investigate the effects of shear stress, mean stress, pore pressure, temperature, and Lode angle on the strength and creep characteristics of salt. The laboratory test data were used in the development of the new criterion. The laboratory results indicate that the strength of salt strongly depends on the mean stress and Lode angle. The strength of the salt does not appear to be sensitive to temperature. Pore pressure effects were not readily apparent until a significant level of damage was induced and the permeability was increased to allow penetration of the liquid permeant. Utilizing the new criterion, numerical simulations were used to estimate the minimum allowable gas pressure for hypothetical storage caverns located in a bedded salt formation. The simulations performed illustrate the influence that cavern roof span, depth, roof salt thickness, shale thickness, and shale stiffness have on the allowable operating pressure range. Interestingly, comparison of predictions using the new criterion with that of a commonly used criterion indicate that lower minimum gas pressures may be allowed for caverns at shallow depths. However, as cavern depth is increased, less conservative estimates for minimum gas pressure were determined by the new criterion.

  13. The joint influence of albedo and insulation on roof performance: An observational study

    SciTech Connect (OSTI)

    Ramamurthy, P.; Sun, T.; Rule, K.; Bou-Zeid, E.

    2015-02-23

    We focus on understanding the temperature and heat flux fields in building roofs, and how they are modulated by the interacting influences of albedo and insulation at annual, seasonal and diurnal scales. High precision heat flux plates and thermocouples were installed over multiple rooftops of varying insulation thickness and albedo in the Northeastern United States to monitor the temperature and the heat flux into and out of the roof structures for a whole year. This analysis shows that while membrane reflectivity (albedo) plays a dominant role in reducing the heat conducted inward through the roof structures during the warmer months, insulation thickness becomes the main roof attribute in preventing heat loss from the buildings during colder months. On a diurnal scale, the thermal state of the white roof structures fluctuated little compared to black roof structures; membrane temperature over white roofs ranged between 10 °C and 45 °C during summer months compared to black membranes that ranged between 10 °C and 80 °C. Insulation thickness, apart from reducing the heat conducted through the roof structure, also delayed the transfer of heat, owing to the thermal inertia of the insulation layer. Furthermore, this has important implications for determining the peak heating and cooling times.

  14. The joint influence of albedo and insulation on roof performance: An observational study

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

    Ramamurthy, P.; Sun, T.; Rule, K.; Bou-Zeid, E.

    2015-02-23

    We focus on understanding the temperature and heat flux fields in building roofs, and how they are modulated by the interacting influences of albedo and insulation at annual, seasonal and diurnal scales. High precision heat flux plates and thermocouples were installed over multiple rooftops of varying insulation thickness and albedo in the Northeastern United States to monitor the temperature and the heat flux into and out of the roof structures for a whole year. This analysis shows that while membrane reflectivity (albedo) plays a dominant role in reducing the heat conducted inward through the roof structures during the warmer months,more » insulation thickness becomes the main roof attribute in preventing heat loss from the buildings during colder months. On a diurnal scale, the thermal state of the white roof structures fluctuated little compared to black roof structures; membrane temperature over white roofs ranged between 10 °C and 45 °C during summer months compared to black membranes that ranged between 10 °C and 80 °C. Insulation thickness, apart from reducing the heat conducted through the roof structure, also delayed the transfer of heat, owing to the thermal inertia of the insulation layer. Furthermore, this has important implications for determining the peak heating and cooling times.« less

  15. A guidebook for insulated low-slope roof systems. IEA Annex 19, Low-slope roof systems: International Energy Agency Energy Conservation in Buildings and Community Systems Programme

    SciTech Connect (OSTI)

    Not Available

    1994-02-01

    Low-slope roof systems are common on commercial and industrial buildings and, to a lesser extent, on residential buildings. Although insulating materials have nearly always been a component of low-slope roofs, the amount of insulation used has increased in the past two decades because of escalation of heating and cooling costs and increased awareness of the need for energy conservation. As the amount of insulation has increased, the demand has intensified for design, installation, and maintenance information specifically for well-insulated roofs. Existing practices for design, installation, and maintenance of insulated roofs have evolved from experience. Typically, these practices feature compromises due to the different properties of materials making up a given roof system. Therefore, they should be examined from time to time to ensure that they are appropriate as new materials continue to enter the market and as the data base on existing systems expands. A primary purpose of this International Energy Agency (IEA) study is to assess current roofing insulation practices in the context of an accumulating data base on performance.

  16. Independent Cost Estimate (ICE)

    Broader source: Energy.gov [DOE]

    Independent Cost Estimate (ICE). On August 8-12, the Office of Project Management Oversight and Assessments (PM) will conduct an ICE on the NNSA Albuquerque Complex Project (NACP) at Albuquerque, NM. This estimate will support the Critical Decision (CD) for establishing the performance baseline and approval to start construction (CD-2/3). This project is at CD-1, with a total project cost range of $183M to $251M.

  17. Assessment of technologies for constructing self-drying low-slope roofs

    SciTech Connect (OSTI)

    Kyle, D.M.; Desjarlais, A.O.

    1994-05-01

    Issues associated with removing excessive moisture from low-slope roofs have been assessed. The economic costs associated with moisture trapped in existing roofs have been estimated. The evidence suggests that existing moisture levels cause approximately a 40% overall reduction in the R-value of installed roofing insulation in the United States. Excess operating costs are further increased by a summertime heat transfer mode unique to wet insulation, caused by the daily migration of water within the roof. By itself, this effect can increase peak electrical demand for air conditioning by roughly 15 W/m{sup 2} of roofing, depending on the type of insulation. This effect will increase peak demand capacity required of utilities in any geographic region (e.g., 900 MW in the South). A simple formula has been derived for predicting the effect that self-drying roofs can have upon time-averaged construction costs. It is presumed that time-averaged costs depend predominantly upon (1) actual service life and (2) the likelihood that the less expensive recover membranes can be installed safely over old roofs. For example, an increase in service life from 15 to 20 years should reduce the current cost of roofing ($12 billion/year) by 21%. Another simple formula for predicting the reroofing waste volume indicates that an increase in service life from 15 to 20 years might reduce the current estimated 0.4 billion ft{sup 3}/year of waste by 25%. A finite-difference computer program has been used to study the flow of heat and moisture within typical existing roofs for a variety of US climates. Nearly all publicly available experimental drying data have been consulted. The drying times for most existing low-slope roofs in the United States are controlled largely climate and the permeability of the structural deck to water vapor.

  18. Seismicity on the western Greenland Ice Sheet: Surface fracture in the vicinity of active moulins

    SciTech Connect (OSTI)

    Carmichael, Joshua D.; Joughin, Ian; Behn, Mark D.; Das, Sarah; King, Matt A.; Stevens, Laura; Lizarralde, Dan

    2015-06-25

    We analyzed geophone and GPS measurements collected within the ablation zone of the western Greenland Ice Sheet during a ~35 day period of the 2011 melt season to study changes in ice deformation before, during, and after a supraglacial lake drainage event. During rapid lake drainage, ice flow speeds increased to ~400% of winter values, and icequake activity peaked. At times >7 days after drainage, this seismicity developed variability over both diurnal and longer periods (~10 days), while coincident ice speeds fell to ~150% of winter values and showed nightly peaks in spatial variability. Approximately 95% of all detected seismicity in the lake basin and its immediate vicinity was triggered by fracture propagation within near-surface ice (<330 m deep) that generated Rayleigh waves. Icequakes occurring before and during drainage frequently were collocated with the down flow (west) end of the primary hydrofracture through which the lake drained but shifted farther west and outside the lake basin after the drainage. We interpret these results to reveal vertical hydrofracture opening and local uplift during the drainage, followed by enhanced seismicity and ice flow on the downstream side of the lake basin. This region collocates with interferometric synthetic aperture radar-measured speedup in previous years and could reflect the migration path of the meltwater supplied to the bed by the lake. The diurnal seismic signal can be associated with nightly reductions in surface melt input that increase effective basal pressure and traction, thereby promoting elevated strain in the surficial ice.

  19. Climate, Ocean and Sea Ice Modeling (COSIM)

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

    Earth, Space Sciences Climate, Ocean and Sea Ice Modeling (COSIM) Climate, Ocean and Sea Ice Modeling (COSIM) The COSIM project develops advanced ocean and ice models for ...

  20. An analysis of moisture accumulation in the roof cavities of manufactured housing

    SciTech Connect (OSTI)

    Burch, D.

    1995-09-01

    A detailed computer analysis is conducted to investigate whether moisture problems occur in the roof cavity of manufactured homes constructed in compliance with the current Department of Housing and Urban Development (HUD) Standards for manufactured housing. The current HUD Standards require a ceiling vapor retarder, but do not require outdoor ventilation of the roof cavity. In cold climates, the analysis revealed that moisture accumulates at lower roof surface and poses a risk of material degradation. The analysis found the following combination of passive measures to be effective in preventing detrimental winter moisture accumulation at lower surface of the roof: (1) providing a ceiling vapor retarder; (2) sealing penetrations and openings in the ceiling construction, and (3) providing natural ventilation openings in the roof cavity. In addition, the performance of a roof cavity exposed to a hot and humid climate is investigated. The analysis revealed that outdoor ventilation of the roof cavity causes the monthly mean relative humidity at the upper surface of the vapor retarder to exceed 80%. This condition is conducive to mold and mildew growth.

  1. Application of Spray Foam Insulation Under Plywood and Oriented Strand Board Roof Sheathing

    SciTech Connect (OSTI)

    Grin, A.; Smegal, J.; Lstiburek, J.

    2013-10-01

    Unvented roof strategies with open cell and closed cell spray polyurethane foam insulation sprayed to the underside of roof sheathing have been used since the mid-1990's to provide durable and efficient building enclosures. However, there have been isolated moisture related incidents reported anecdotally that raise potential concerns about the overall hygrothermal performance of these systems. The incidents related to rainwater leakage and condensation concerns. Condensation concerns have been extensively studied by others and are not further discussed in this report. This project involved hygrothermal modeling of a range of rainwater leakage and field evaluations of in-service residential roofs using spray foam insulation. All of the roof assemblies modeled exhibited drying capacity to handle minor rainwater leakage. All field evaluation locations of in-service residential roofs had moisture contents well within the safe range for wood-based sheathing. Explorations of eleven in-service roof systems were completed. The exploration involved taking a sample of spray foam from the underside of the roof sheathing, exposing the sheathing, then taking a moisture content reading. All locations had moisture contents well within the safe range for wood-based sheathing. One full-roof failure was reviewed, as an industry partner was involved with replacing structurally failed roof sheathing. In this case the manufacturer's investigation report concluded that the spray foam was installed on wet OSB based on the observation that the spray foam did not adhere well to the substrate and the pore structure of the closed cell spray foam at the ccSPF/OSB interface was indicative of a wet substrate.

  2. Icing rate meter estimation of in-cloud cable icing

    SciTech Connect (OSTI)

    McComber, P.; Druez, J.; Laflamme, J.

    1994-12-31

    In many northern countries, the design and reliability of power transmission lines are closely related to atmospheric icing overloads. It is becoming increasingly important to have reliable instrument systems to warn of icing conditions before icing loads become sufficient to damage the power transmission network. Various instruments are presently being developed to provide better monitoring of icing conditions. One such instrument is the icing rate meter (IRM) which counts icing and de-icing cycles per unit time on a standard probe and can be used to estimate the icing rate on nearby cables. The calibration presently used was originally based on experiments conducted in a cold room. Even though this calibration has shown that the IRM estimation already offers an improvement over model prediction based on standard meteorological parameters, it can certainly be improved further with appropriate field data. For this purpose, the instrument was tested on an icing test site at Mt. Valin (altitude 902 m) Quebec, Canada. In this paper measurements from twelve in-cloud icing events during the 1991--92 winter are divided into one hour periods of icing to provide the experimental icing rate data. The icing rates measured on a 12.5 mm and a 35 mm cables are then compared with the number of IRM signals, also for one hour periods, in relation to initial ice load, temperature, wind velocity and direction. From this analysis, a better calibration for the IRM instrument is suggested. The improvement of the IRM estimation is illustrated by making a comparison with measurements, of the icing load estimation with the old and new calibrations for two complete icing events.

  3. The Effects of Infrared-Blocking Pigments and Deck Venting on Stone-Coated Metal Residential Roofs

    SciTech Connect (OSTI)

    Miller, William A

    2006-01-01

    Field data show that stone-coated metal shakes and S-mission tile, which exploit the use of infraredblocking color pigments (IrBCPs), along with underside venting reduce the heat flow penetrating the conditioned space of a residence by 70% compared with the amount of heat flow penetrating roofs with conventional asphalt shingles. Stone-coated metal roof products are typically placed on battens and counter-battens and nailed through the battens to the roof deck. The design provides venting on the underside of the metal roof that reduces the heat flow penetrating a home. The Metal Construction Association (MCA) and its affiliate members installed stone-coated metal roofs with shake and S-mission tile profiles and a painted metal shake roof on a fully instrumented attic test assembly at Oak Ridge National Laboratory (ORNL). Measurements of roof, deck, attic, and ceiling temperatures; heat flows; solar reflectance; thermal emittance; and ambient weather were recorded for each of the test roofs and also for an adjacent attic cavity covered with a conventional pigmented and direct nailed asphalt shingle roof. All attic assemblies had ridge and soffit venting; the ridge was open to the underside of the stone-coated metal roofs. A control assembly with a conventional asphalt shingle roof was used for comparing deck and ceiling heat transfer rates.

  4. CX-008978: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Parking Garage Gutter Replacement and Installation of Roof Ice Melt System CX(s) Applied: B2.3, B2.5 Date: 08/01/2012 Location(s): West Virginia Offices(s): National Energy Technology Laboratory

  5. Fatal accidents involving roof falls in coal mining, 1996--1998

    SciTech Connect (OSTI)

    Not Available

    1999-01-01

    This publication presents information on fatalities involving roof and rib falls that occurred in coal mining operations from January 1996 through December 1998. It includes statistics for the fatalities, as well as abstracts, best practices and illustrations. Conclusion statements have been substituted for best practices where no Title 30 Code of Regulations violations were cited during the accident investigation. From January 1996 through December 1998, 36 miners died at coal operations from accidents classified as roof falls. The information in the report is based on statistics taken from the 1996 through 1998 MSHA Fatal Illustration Programs: Roof Fall Fatalities by District.

  6. Fatal accidents involving roof falls in coal mining, 1996--1998

    SciTech Connect (OSTI)

    1999-11-01

    This publication presents information on fatalities involving roof and rib falls that occurred in coal mining operations from January 1996 through December 1998. It includes statistics for the fatalities, as well as abstracts, best practices and illustrations. Conclusion statements have been substituted for best practices where no Title 30 Code of Regulations violations were cited during the accident investigation. From January 1996 through December 1998, 36 miners died at coal operations from accidents classified as roof falls. The information in the report is based on statistics taken from the 1996 through 1998 MSHA Fatal Illustration Programs: Roof Fall Fatalities by District.

  7. Field Evaluation of Four Novel Roof Designs for Energy-Efficient Manufactured Homes

    SciTech Connect (OSTI)

    Levy, E.; Dentz, J.; Ansanelli, E.; Barker, G.; Rath, P.; Dadia, D.

    2015-12-03

    "9A five-bay roof test structure was built, instrumented and monitored in an effort to determine through field testing and analysis the relative contributions of select technologies toward reducing energy use in new manufactured homes. The roof structure in Jamestown, California was designed to examine how differences in roof construction impact space conditioning loads, wood moisture content and attic humidity levels. Conclusions are drawn from the data on the relative energy and moisture performance of various configurations of vented and sealed attics.

  8. What's on your Roof? Rooftop Unit (RTU) Efficiency Advice and Guidance

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

    from the Advanced RTU Campaign | Department of Energy What's on your Roof? Rooftop Unit (RTU) Efficiency Advice and Guidance from the Advanced RTU Campaign What's on your Roof? Rooftop Unit (RTU) Efficiency Advice and Guidance from the Advanced RTU Campaign November 10, 2015 - 11:40am Addthis What’s on your Roof? Rooftop Unit (RTU) Efficiency Advice and Guidance from the Advanced RTU Campaign By Marta Schantz This is the first in a series of upcoming blogs on DOE's Advanced Rooftop Unit

  9. Impact of Solar PV Laminate Membrane Systems on Roofs | Department of

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

    Energy Impact of Solar PV Laminate Membrane Systems on Roofs Impact of Solar PV Laminate Membrane Systems on Roofs In 2008, CH2M HILL performed a solar site analysis of the HP Pavilion facility for the City of San José under the Department of Energy's Solar America Showcase program. Based on weight loading requirements of the facility's roof, CH2M HILL recommended a building integrated photovoltaic (BIPV) product that consists of thin-film, flexible photovoltaic modules that can be

  10. Stay-Clean and Durable White Elastomeric Roof Coatings | Department of

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

    Energy Stay-Clean and Durable White Elastomeric Roof Coatings Stay-Clean and Durable White Elastomeric Roof Coatings Lead Performer: Lawrence Berkeley National Laboratory - Berkeley, CA Partner: Dow Chemical - Midland, MI DOE Funding: $570,000 Cost Share: $449,000 Project Term: 10/1/2011 - 9/30/2014 Project Objective This project is developing stay-clean white elastomeric roof coatings (ERCs) with a three-year aged solar reflectance (SR) of at least 0.75 and a service life of 15 years or

  11. Contractor SOW Template – ICE

    Broader source: Energy.gov [DOE]

    The template presented here is a Statement of Work (SOW) for services of an ICE Support Contractor for assisting OECM in conducting an ICE. Project and review specific information should be incorporated.

  12. Improving the System Life of Basic Oxygen and Electric Arc Furnace Hoods, Roofs, and Side Vents

    Broader source: Energy.gov [DOE]

    This factsheet describes the benefits of a high-performance aluminum bronze alloy to basic oxygen furnace and electric arc furnace components such as hoods, roofs, and side vents.

  13. Using remote sensing to quantify albedo of roofs in seven California...

    Office of Scientific and Technical Information (OSTI)

    1: Methods Citation Details In-Document Search This content will become publicly available on March 14, 2017 Title: Using remote sensing to quantify albedo of roofs in seven ...

  14. A meeting of the minds when NYC CoolRoofs visits PPPL | Princeton...

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

    which collected data on three white "cool roofs," including one on the Museum of Modern Art Queens in Long Island City, and found there was a 42 degree Fahrenheit difference...

  15. Evolution of cool-roof standards in the United States (Journal...

    Office of Scientific and Technical Information (OSTI)

    high solar reflectance and high thermal emittance stay cool in the sun. A roof with lower thermal emittance but exceptionally high solar reflectance can also stay cool in the sun. ...

  16. Measured Energy Savings from the Application of Reflective Roofs in 3 AT and T Regeneration Buildings

    SciTech Connect (OSTI)

    Akbari, Hashen; Rainer, Leo

    2000-11-01

    Energy use and environmental parameters were monitored in three AT and T regeneration buildings during the summer of 2000. These buildings are constructed with concrete and are about 14.9 m2 (160 f2; 10x16 ft)in size. The buildings were initially monitored for about 1 1/2 months to establish a base condition. Then, the roofs of the buildings were painted with a white coating and the monitoring was continued. The original roof reflectances were about 26 percent; after the application of roof coatings the reflectivities increased to about 72 percent. In two of these buildings, we monitored savings of about 0.5kWh per day (8.6 kWh/m2 [0.8 kWh/ft2]). The third building showed a reduction in air-conditioning energy use of about 13kWh per day. These savings probably resulted from the differences in the performance (EER) of the two dissimilar AC units in this building. The estimated annual savings for two of the buildings are about 125kWh per year; at a cost of dollar 0.1/kWh, savings are about dollar 12.5 per year. Obviously, it costs significantly more than this amount to coat the roofs with reflective coating, particularly because of the remote location of the buildings. However, since the prefabricated roofs are already painted green at the factory, painting them with white (reflective) color would bring no additional cost. Hence the payback time for having reflective roofs is nil, and the reflective roofs save an accumulated 370kWh over 30 years of the life of the roof.

  17. The Trade-off between Solar Reflectance and Above-Sheathing Ventilation for Metal Roofs on Residential and Commercial Buildings

    SciTech Connect (OSTI)

    Desjarlais, Andre Omer; Kriner, Scott; Miller, William A

    2013-01-01

    An alternative to white and cool-color roofs that meets prescriptive requirements for steep-slope (residential and non-residential) and low-slope (non-residential) roofing has been documented. Roofs fitted with an inclined air space above the sheathing (herein termed above-sheathing ventilation, or ASV), performed as well as if not better than high-reflectance, high-emittance roofs fastened directly to the deck. Field measurements demonstrated the benefit of roofs designed with ASV. A computer tool was benchmarked against the field data. Testing and benchmarks were conducted at roofs inclined at 18.34 ; the roof span from soffit to ridge was 18.7 ft (5.7 m). The tool was then exercised to compute the solar reflectance needed by a roof equipped with ASV to exhibit the same annual cooling load as that for a direct-to-deck cool-color roof. A painted metal roof with an air space height of 0.75 in. (0.019 m) and spanning 18.7 ft (5.7 m) up the roof incline of 18.34 needed only a 0.10 solar reflectance to exhibit the same annual cooling load as a direct-to-deck cool-color metal roof (solar reflectance of 0.25). This held for all eight ASHRAE climate zones complying with ASHRAE 90.1 (2007a). A dark heat-absorbing roof fitted with 1.5 in. (0.038 m) air space spanning 18.7 ft (5.7 m) and inclined at 18.34 was shown to have a seasonal cooling load equivalent to that of a conventional direct-to-deck cool-color metal roof. Computations for retrofit application based on ASHRAE 90.1 (1980) showed that ASV air spaces of either 0.75 or 1.5 in. (0.019 and 0.038 m) would permit black roofs to have annual cooling loads equivalent to the direct-to-deck cool roof. Results are encouraging, and a parametric study of roof slope and ASV aspect ratio is needed for developing guidelines applicable to all steep- and low-slope roof applications.

  18. ARM - TWP-ICE Maps

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

    TWP-ICE Maps Related Links TWP-ICE Home Tropical Western Pacific Home ARM Data Discovery Browse Data Post-Experiment Data Sets Weather Summary (pdf, 6M) New York Workshop Presentations Experiment Planning TWP-ICE Proposal Abstract Detailed Experiment Description Science Plan (pdf, 1M) Operations Plan (pdf, 321K) Maps Contact Info Related Links Daily Report Report Archives Press Media Coverage TWP-ICE Fact Sheet (pdf, 211K) Press Releases TWP-ICE Images ARM flickr site <=""

  19. Analysis of DOE s Roof Savings Calculator with Comparison to other Simulation Engines

    SciTech Connect (OSTI)

    New, Joshua Ryan; Huang, Yu; Levinson, Ronnen; Mellot, Joe; Sanyal, Jibonananda; Childs, Kenneth W

    2014-01-01

    A web-based Roof Savings Calculator (RSC) has been deployed for the Department of Energy as an industry-consensus tool to help building owners, manufacturers, distributors, contractors and researchers easily run complex roof and attic simulations. This tool employs the latest web technologies and usability design to provide an easy input interface to an annual simulation of hour-by-hour, whole-building performance using the world-class simulation tools DOE-2.1E and AtticSim. Building defaults were assigned based on national averages and can provide estimated annual energy and cost savings after the user selects nothing more than building location. In addition to cool reflective roofs, the RSC tool can simulate multiple roof and attic configurations including different roof slopes, above sheathing ventilation, radiant barriers, low-emittance surfaces, HVAC duct location, duct leakage rates, multiple layers of building materials, ceiling and deck insulation levels, and other parameters. A base case and energy-efficient alternative can be compared side-by-side to generate an energy/cost savings estimate between two buildings. The RSC tool was benchmarked against field data for demonstration homes in Ft. Irwin, CA. However, RSC gives different energy savings estimates than previous cool roof simulation tools so more thorough software and empirical validation proved necessary. This report consolidates much of the preliminary analysis for comparison of RSC s projected energy savings to that from other simulation engines.

  20. Performance Evaluation of Advanced Retrofit Roof Technologies Using Field-Test Data Phase Three Final Report, Volume 1

    SciTech Connect (OSTI)

    Biswas, Kaushik; Childs, Phillip W; Atchley, Jerald Allen

    2014-05-01

    This article presents various metal roof configurations that were tested at Oak Ridge National Laboratory in Tennessee, U.S.A. between 2009 and 2013, and describes their potential for reducing the attic-generated space conditioning loads. These roofs contained different combinations of phase change material, rigid insulation, low emittance surface and above-sheathing ventilation, with standing-seam metal panels on top. These roofs were designed to be installed on existing roofs decks, or on top of asphalt shingles for retrofit construction. All the tested roofs showed the potential for substantial energy savings compared to an asphalt shingle roof, which was used as a control for comparison. The roofs were constructed on a series of adjacent attics separated at the gables using thick foam insulation. The attics were built on top of a conditioned room. All attics were vented at the soffit and ridge. The test roofs and attics were instrumented with an array of thermocouples. Heat flux transducers were installed in the roof deck and attic floor (ceiling) to measure the heat flows through the roof and between the attic and conditioned space below. Temperature and heat flux data were collected during the heating, cooling and swing seasons over a 3 year period. Data from previous years of testing have been published. Here, data from the latest roof configurations being tested in year 3 of the project are presented. All test roofs were highly effective in reducing the heat flows through the roof and ceiling, and in reducing the diurnal attic temperature fluctuations.

  1. Ice Storm Supercomputer

    ScienceCinema (OSTI)

    None

    2013-05-28

    "A new Idaho National Laboratory supercomputer is helping scientists create more realistic simulations of nuclear fuel. Dubbed 'Ice Storm,' this 2048-processor machine allows researchers to model and predict the complex physics behind nuclear reactor behavior. And with a new visualization lab, the team can see the results of its simulations on the big screen." For more information about INL research, visit http://www.facebook.com/idahonationallaboratory.

  2. Developing vanadium valence state oxybarometers (spinel-melt...

    Office of Scientific and Technical Information (OSTI)

    olivine-melt, spinel-olivine) and V(Cr+Al) partitioning (spinel-melt) for ... olivine-melt, spinel-olivine) and V(Cr+Al) partitioning (spinel-melt) for ...

  3. Condition Assessment Survey (CAS) Program. Deficiency standards and inspections methods manual: Volume 5, 0.05 Roofing

    SciTech Connect (OSTI)

    Not Available

    1993-05-01

    General information is presented for asset determinant factor/CAS repair codes/CAS cost factors; guide sheet tool & material listing; testing methods; inspection frequency; standard system design life tables; and system work breakdown structure. Deficiency standards and inspection methods are presented for built-up membrane; single- ply membrane; metal roofing systems; coated foam membrane; shingles; tiles; parapets; roof drainage system; roof specialties; and skylights.

  4. Quantum Hooke's Law to classify pulse laser induced ultrafast melting

    SciTech Connect (OSTI)

    Hu, Hao; Ding, Hepeng; Liu, Feng

    2015-02-03

    Ultrafast crystal-to-liquid phase transition induced by femtosecond pulse laser excitation is an interesting material's behavior manifesting the complexity of light-matter interaction. There exist two types of such phase transitions: one occurs at a time scale shorter than a picosecond via a nonthermal process mediated by electron-hole plasma formation; the other at a longer time scale via a thermal melting process mediated by electron-phonon interaction. However, it remains unclear what material would undergo which process and why? Here, by exploiting the property of quantum electronic stress (QES) governed by quantum Hooke's law, we classify the transitions by two distinct classes of materials: the faster nonthermal process can only occur in materials like ice having an anomalous phase diagram characterized with dTm/dP < 0, where Tm is the melting temperature and P is pressure, above a high threshold laser fluence; while the slower thermal process may occur in all materials. Especially, the nonthermal transition is shown to be induced by the QES, acting like a negative internal pressure, which drives the crystal into a super pressing state to spontaneously transform into a higher-density liquid phase. Our findings significantly advance fundamental understanding of ultrafast crystal-to-liquid phase transitions, enabling quantitative a priori predictions.

  5. Quantum Hooke's Law to classify pulse laser induced ultrafast melting

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

    Hu, Hao; Ding, Hepeng; Liu, Feng

    2015-02-03

    Ultrafast crystal-to-liquid phase transition induced by femtosecond pulse laser excitation is an interesting material's behavior manifesting the complexity of light-matter interaction. There exist two types of such phase transitions: one occurs at a time scale shorter than a picosecond via a nonthermal process mediated by electron-hole plasma formation; the other at a longer time scale via a thermal melting process mediated by electron-phonon interaction. However, it remains unclear what material would undergo which process and why? Here, by exploiting the property of quantum electronic stress (QES) governed by quantum Hooke's law, we classify the transitions by two distinct classes ofmore » materials: the faster nonthermal process can only occur in materials like ice having an anomalous phase diagram characterized with dTm/dP < 0, where Tm is the melting temperature and P is pressure, above a high threshold laser fluence; while the slower thermal process may occur in all materials. Especially, the nonthermal transition is shown to be induced by the QES, acting like a negative internal pressure, which drives the crystal into a “super pressing” state to spontaneously transform into a higher-density liquid phase. Our findings significantly advance fundamental understanding of ultrafast crystal-to-liquid phase transitions, enabling quantitative a priori predictions.« less

  6. Winter Preparedness ? Slips on Ice

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

    can further increase traction; however, they must be removed when ice is no longer present, because their use on floors, smooth concrete, or gravel, presents a different...

  7. Climate Impacts of Ice Nucleation

    SciTech Connect (OSTI)

    Gettelman, A.; Liu, Xiaohong; Barahona, Donifan; Lohmann, U.; Chen, Chih-Chieh

    2012-10-27

    Several different ice nucleation parameterizations in two different General Circulation Models are used to understand the effects of ice nucleation on the mean climate state, and the climate effect of aerosol perturbations to ice clouds. The simulations have different ice microphysical states that are consistent with the spread of observations. These different states occur from different parameterizations of the ice cloud nucleation processes, and feature different balances of homogeneous and heterogeneous nucleation. At reasonable efficiencies, consistent with laboratory measurements and constrained by the global radiative balance, black carbon has a small (-0.06 Wm?2) and not statistically significant climate effect. Indirect effects of anthropogenic aerosols on cirrus clouds occur mostly due to increases in homogeneous nucleation fraction as a consequence of anthropogenic sulfur emissions. The resulting ice indirect effects do not seem strongly dependent on the ice micro-physical balance, but are slightly larger for those states with less homogeneous nucleation in the base state. The total ice AIE is estimated at 0.260.09 Wm?2 (1? uncertainty). This represents an offset of 20-30% of the simulated total Aerosol Indirect Effect for ice and liquid clouds.

  8. Application of Spray Foam Insulation Under Plywood and OSB Roof Sheathing (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2013-11-01

    Spray polyurethane foams (SPFs) have advantages over alternative insulation methods because they provide air sealing in complex assemblies, particularly roofs. Spray foam can provide the thermal, air, and vapor control layers in both new and retrofit construction. Unvented roof strategies with open cell and closed cell SPF insulation sprayed to the underside of roof sheathing have been used since the mid-1990s to provide durable and efficient building enclosures. However, there have been isolated incidents of failures (either sheathing rot or SPF delamination) that raise some general concerns about the hygrothermal performance and durability of these systems. The primary risks for roof systems are rainwater leaks, condensation from diffusion and air leakage, and built-in construction moisture. This project directly investigated rain and indirectly investigated built-in construction moisture and vapor drives. Research involved both hygrothermal modeling of a range of rain water leakage scenarios and field evaluations of in-service residential roofs. Other variables considered were climate zone, orientation, interior relative humidity, and the vapor permeance of the coating applied to the interior face of open cell SPF.

  9. Technology Solutions Case Study: Application of Spray Foam Insulation Under Plywood and OSB Roof Sheathing

    SciTech Connect (OSTI)

    2013-11-01

    Spray polyurethane foams (SPFs) have advantages over alternative insulation methods because they provide air sealing in complex assemblies, particularly roofs. Spray foam can provide the thermal, air, and vapor control layers in both new and retrofit construction. Unvented roof strategies with open cell and closed cell SPF insulation sprayed to the underside of roof sheathing have been used since the mid-1990s to provide durable and efficient building enclosures. However, there have been isolated incidents of failures (either sheathing rot or SPF delamination) that raise some general concerns about the hygrothermal performance and durability of these systems. The primary risks for roof systems are rainwater leaks, condensation from diffusion and air leakage, and built-in construction moisture. In this project, Building Science Corporation investigated rain and built-in construction moisture and vapor drives. Research involved both hygrothermal modeling of a range of rain water leakage scenarios and field evaluations of in-service residential roofs. Other variables considered were climate zone, orientation, interior relative humidity, and the vapor permeance of the coating applied to the interior face of open cell SPF.

  10. Modeling the impediment of methane ebullition bubbles by seasonal lake ice

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

    Greene, S.; Walter Anthony, K. M.; Archer, D.; Sepulveda-Jauregui, A.; Martinez-Cruz, K.

    2014-07-15

    Microbial methane (CH4) ebullition (bubbling) from anoxic lake sediments comprises a globally significant flux to the atmosphere, but ebullition bubbles in temperate and polar lakes can be trapped by winter ice cover and later released during spring thaw. This "ice-bubble storage" (IBS) constitutes a novel mode of CH4 emission. Before bubbles are encapsulated by downward-growing ice, some of their CH4 dissolves into the lake water, where it may be subject to oxidation. We present field characterization and a model of the annual CH4 cycle in Goldstream Lake, a thermokarst (thaw) lake in interior Alaska. We find that summertime ebullition dominatesmore » annual CH4 emissions to the atmosphere. Eighty percent of CH4 in bubbles trapped by ice dissolves into the lake water column in winter, and about half of that is oxidized. The ice growth rate and the magnitude of the CH4 ebullition flux are important controlling factors of bubble dissolution. Seven percent of annual ebullition CH4 is trapped as IBS and later emitted as ice melts. In a future warmer climate, there will likely be less seasonal ice cover, less IBS, less CH4 dissolution from trapped bubbles, and greater CH4 emissions from northern lakes.« less