Science.gov

Sample records for roof integrated solar

  1. High Efficiency Solar Integrated Roof Membrane Product

    SciTech Connect

    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.

  2. Million Solar Roofs

    SciTech Connect

    2003-11-01

    Since its announcement in June 1997, the Million Solar Roofs Initiative has generated a major buzz in communities, states, and throughout the nation. With more than 300,000 installations, the buzz is getting louder. This brochure describes Million Solar Roofs activities and partnerships.

  3. Solar power roof shingle

    NASA Technical Reports Server (NTRS)

    Forestieri, A. F.; Ratajczak, A. F.; Sidorak, L. G.

    1975-01-01

    Silicon solar cell module provides both all-weather protection and electrical power. Module consists of array of circular silicon solar cells bonded to fiberglass substrate roof shingle with fluorinated ethylene propylene encapsulant.

  4. Million Solar Roofs Flyer (Revision)

    SciTech Connect

    Not Available

    2000-11-01

    The Million Solar Roofs Initiative, announced in June 1997, assists businesses and communities in installing solar energy systems on one million buildings across the United States by 2010. The US Department of Energy leads this trailblazing initiative by partnering with the building industry, local governments, state agencies, the solar industry, electric service providers, and non-governmental organizations to remove barriers and strengthen the demand for solar technologies.

  5. 30 CFR 75.205 - Installation of roof support using mining machines with integral roof bolters.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... machines with integral roof bolters. 75.205 Section 75.205 Mineral Resources MINE SAFETY AND HEALTH... Roof Support § 75.205 Installation of roof support using mining machines with integral roof bolters. When roof bolts are installed by a continuous mining machine with intregal roof bolting equipment:...

  6. 30 CFR 75.205 - Installation of roof support using mining machines with integral roof bolters.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... machines with integral roof bolters. 75.205 Section 75.205 Mineral Resources MINE SAFETY AND HEALTH... Roof Support § 75.205 Installation of roof support using mining machines with integral roof bolters. When roof bolts are installed by a continuous mining machine with intregal roof bolting equipment:...

  7. 30 CFR 75.205 - Installation of roof support using mining machines with integral roof bolters.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... machines with integral roof bolters. 75.205 Section 75.205 Mineral Resources MINE SAFETY AND HEALTH... Roof Support § 75.205 Installation of roof support using mining machines with integral roof bolters. When roof bolts are installed by a continuous mining machine with intregal roof bolting equipment:...

  8. 30 CFR 75.205 - Installation of roof support using mining machines with integral roof bolters.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... machines with integral roof bolters. 75.205 Section 75.205 Mineral Resources MINE SAFETY AND HEALTH... Roof Support § 75.205 Installation of roof support using mining machines with integral roof bolters. When roof bolts are installed by a continuous mining machine with intregal roof bolting equipment:...

  9. 30 CFR 75.205 - Installation of roof support using mining machines with integral roof bolters.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Installation of roof support using mining machines with integral roof bolters. 75.205 Section 75.205 Mineral Resources MINE SAFETY AND HEALTH... Roof Support § 75.205 Installation of roof support using mining machines with integral roof...

  10. Integrated roof wind energy system

    NASA Astrophysics Data System (ADS)

    Suma, A. B.; Ferraro, R. M.; Dano, B.; Moonen, S. P. G.

    2012-10-01

    Wind is an attractive renewable source of energy. Recent innovations in research and design have reduced to a few alternatives with limited impact on residential construction. Cost effective solutions have been found at larger scale, but storage and delivery of energy to the actual location it is used, remain a critical issue. The Integrated Roof Wind Energy System is designed to overcome the current issues of urban and larger scale renewable energy system. The system is built up by an axial array of skewed shaped funnels that make use of the Venturi Effect to accelerate the wind flow. This inventive use of shape and geometry leads to a converging air capturing inlet to create high wind mass flow and velocity toward a vertical-axis wind turbine in the top of the roof for generation of a relatively high amount of energy. The methods used in this overview of studies include an array of tools from analytical modelling, PIV wind tunnel testing, and CFD simulation studies. The results define the main design parameters for an efficient system, and show the potential for the generation of high amounts of renewable energy with a novel and effective system suited for the built environment.

  11. Structurally integrated steel solar collector

    DOEpatents

    Moore, S.W.

    1975-06-03

    Herein is disclosed a flate plate solar heat collector unit. The solar collector is integrated as a structural unit so that the collector also functions as the building roof. The functions of efficient heat collection, liquid coolant flow passages, roof structural support, and building insulation are combined into one unit.

  12. Structurally integrated steel solar collector

    DOEpatents

    Moore, Stanley W.

    1977-03-08

    Herein is disclosed a flat plate solar heat collector unit. The solar collector is integrated as a structural unit so that the collector also functions as the building roof. The functions of efficient heat collection, liquid coolant flow passages, roof structural support and building insulation are combined into one unit.

  13. Innovative Ballasted Flat Roof Solar PV Racking System

    SciTech Connect

    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.

  14. Equilibrium thermal characteristics of a building integrated photovoltaic tiled roof

    SciTech Connect

    Mei, L.; Gottschalg, R.; Loveday, D.L.; Infield, D.G.; Davies, D.; Berry, M.

    2009-10-15

    Photovoltaic (PV) modules attain high temperatures when exposed to a combination of high radiation levels and elevated ambient temperatures. The temperature rise can be particularly problematic for fully building integrated PV (BIPV) roof tile systems if back ventilation is restricted. PV laminates could suffer yield degradation and accelerated aging in these conditions. This paper presents a laboratory based experimental investigation undertaken to determine the potential for high temperature operation in such a BIPV installation. This is achieved by ascertaining the dependence of the PV roof tile temperature on incident radiation and ambient temperature. A theory based correction was developed to account for the unrealistic sky temperature of the solar simulator used in the experiments. The particular PV roof tiles used are warranted up to an operational temperature of 85 C, anything above this temperature will void the warranty because of potential damage to the integrity of the encapsulation. As a guide for installers, a map of southern Europe has been generated indicating locations where excessive module temperatures might be expected and thus where installation is inadvisable. (author)

  15. Solare Cell Roof Tile And Method Of Forming Same

    DOEpatents

    Hanoka, Jack I.; Real, Markus

    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.

  16. Effects of Solar Photovoltaic Panels on Roof Heat Transfer

    NASA Technical Reports Server (NTRS)

    Dominguez, A.; Klessl, J.; Samady, M.; Luvall, J. C.

    2010-01-01

    Building Heating, Ventilation and Air Conditioning (HVAC) is a major contributor to urban energy use. In single story buildings with large surface area such as warehouses most of the heat enters through the roof. A rooftop modification that has not been examined experimentally is solar photovoltaic (PV) arrays. In California alone, several GW in residential and commercial rooftop PV are approved or in the planning stages. With the PV solar conversion efficiency ranging from 5-20% and a typical installed PV solar reflectance of 16-27%, 53-79% of the solar energy heats the panel. Most of this heat is then either transferred to the atmosphere or the building underneath. Consequently solar PV has indirect effects on roof heat transfer. The effect of rooftop PV systems on the building roof and indoor energy balance as well as their economic impacts on building HVAC costs have not been investigated. Roof calculator models currently do not account for rooftop modifications such as PV arrays. In this study, we report extensive measurements of a building containing a flush mount and a tilted solar PV array as well as exposed reference roof. Exterior air and surface temperature, wind speed, and solar radiation were measured and thermal infrared (TIR) images of the interior ceiling were taken. We found that in daytime the ceiling surface temperature under the PV arrays was significantly cooler than under the exposed roof. The maximum difference of 2.5 C was observed at around 1800h, close to typical time of peak energy demand. Conversely at night, the ceiling temperature under the PV arrays was warmer, especially for the array mounted flat onto the roof. A one dimensional conductive heat flux model was used to calculate the temperature profile through the roof. The heat flux into the bottom layer was used as an estimate of the heat flux into the building. The mean daytime heat flux (1200-2000 PST) under the exposed roof in the model was 14.0 Watts per square meter larger than under the tilted PV array. The maximum downward heat flux was 18.7 Watts per square meters for the exposed roof and 7.0 Watts per square meters under the tilted PV array, a 63% reduction due to the PV array. This study is unique as the impact of tilted and flush PV arrays could be compared against a typical exposed roof at the same roof for a commercial uninhabited building with exposed ceiling and consisting only of the building envelope. Our results indicate a more comfortable indoor environment in PV covered buildings without HVAC both in hotter and cooler seasons.

  17. Estimation of Solar Radiation on Building Roofs in Mountainous Areas

    NASA Astrophysics Data System (ADS)

    Agugiaro, G.; Remondino, F.; Stevanato, G.; De Filippi, R.; Furlanello, C.

    2011-04-01

    The aim of this study is estimating solar radiation on building roofs in complex mountain landscape areas. A multi-scale solar radiation estimation methodology is proposed that combines 3D data ranging from regional scale to the architectural one. Both the terrain and the nearby building shadowing effects are considered. The approach is modular and several alternative roof models, obtained by surveying and modelling techniques at varying level of detail, can be embedded in a DTM, e.g. that of an Alpine valley surrounded by mountains. The solar radiation maps obtained from raster models at different resolutions are compared and evaluated in order to obtain information regarding the benefits and disadvantages tied to each roof modelling approach. The solar radiation estimation is performed within the open-source GRASS GIS environment using r.sun and its ancillary modules.

  18. Detail of parachute tower showing integration with main roof form, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail of parachute tower showing integration with main roof form, facing southwest. - Albrook Air Force Station, Parachute & Armament Building, 200 feet north of Andrews Boulevard, Balboa, Former Panama Canal Zone, CZ

  19. Laying the Foundation for a Solar America: The Million Solar Roofs Initiative

    SciTech Connect

    Strahs, G.; Tombari, C.

    2006-10-01

    As the U.S. Department of Energy's Solar Energy Technology Program embarks on the next phase of its technology acceptance efforts under the Solar America Initiative, there is merit to examining the program's previous market transformation effort, the Million Solar Roofs Initiative. Its goal was to transform markets for distributed solar technologies by facilitating the installation of solar systems.

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

    SciTech Connect

    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).

  1. Analysis of Wind Forces on Roof-Top Solar Panel

    NASA Astrophysics Data System (ADS)

    Panta, Yogendra; Kudav, Ganesh

    2011-03-01

    Structural loads on solar panels include forces due to high wind, gravity, thermal expansion, and earthquakes. International Building Code (IBC) and the American Society of Civil Engineers are two commonly used approaches in solar industries to address wind loads. Minimum Design Loads for Buildings and Other Structures (ASCE 7-02) can be used to calculate wind uplift loads on roof-mounted solar panels. The present study is primarily focused on 2D and 3D modeling with steady, and turbulent flow over an inclined solar panel on the flat based roof to predict the wind forces for designing wind management system. For the numerical simulation, 3-D incompressible flow with the standard k- ɛ was adopted and commercial CFD software ANSYS FLUENT was used. Results were then validated with wind tunnel experiments with a good agreement. Solar panels with various aspect ratios for various high wind speeds and angle of attacks were modeled and simulated in order to predict the wind loads in various scenarios. The present study concluded to reduce the strong wind uplift by designing a guide plate or a deflector before the panel. Acknowledgments to Northern States Metal Inc., OH (GK & YP) and School of Graduate Studies of YSU for RP & URC 2009-2010 (YP).

  2. Solar heat collection with suspended metal roofing and whole house ventilation

    SciTech Connect

    Maynard, T.

    1996-10-01

    A south pitched roof is employed for solar collection directly onto a roofing with chocolate brown color. The roofing is structural and is suspended over plywood decking so as to create an air space which receives input from the coolest and lowest basement air of the house interior. Air heated beneath the metal roofing is returned to a basement storage wall. Full length plenum cavities are formed into the ordinary rafter truss framing--at the knee wall and collar tie spaces. Preliminary testing of BTU gain at known air flows is acquired with a microprocessor system continuously collecting input and output temperatures at the roof collector into disk data files.

  3. Solar Radiation Estimation on Building Roofs and Web-Based Solar Cadastre

    NASA Astrophysics Data System (ADS)

    Agugiaro, G.; Nex, F.; Remondino, F.; De Filippi, R.; Droghetti, S.; Furlanello, C.

    2012-07-01

    The aim of this study is the estimation of solar irradiance on building roofs in complex Alpine landscapes. Very high resolution geometric models of the building roofs are generated by means of advanced automated image matching methods. Models are combined with raster and vector data sources to estimate the incoming solar radiation hitting the roofs. The methodology takes into account for atmospheric effects, site latitude and elevation, slope and aspect of the terrain as well as the effects of shadows cast by surrounding buildings, chimneys, dormers, vegetation and terrain topography. An open source software solution has been developed and applied to a study area located in a mountainous site and containing some 1250 residential, commercial and industrial buildings. The method has been validated by data collected with a pyranometer and results made available through a prototype WebGIS platform.

  4. Roof Savings Calculator Suite

    Energy Science and Technology Software Center (ESTSC)

    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

  5. Roof Savings Calculator Suite

    SciTech Connect

    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.

  6. Technical evaluation of a USSC Integrated/Direct Mount PV Roofing Module system at NREL

    SciTech Connect

    Strand, T.; Hansen, R.; Mrig, L.

    1995-05-01

    The results of a 16 month technical evaluation performed on a nominal 1 kW{sub ac} utility-interconnect amorphous silicon PV system deployed at the National Renewable Energy Laboratory`s PV outdoor test site are given here. The system employs 64 prototype United Solar Systems Corp. Integrated/Direct Mount PV Roofing Modules mounted on simulated attic/roof structures. In this paper we show that the PV array fill factor has been relatively stable with respect to time and that the seasonal variations in performance can be largely attributed to seasonal variations in current. We also show that in determining the summer and winter ac power output, the summation of the manufacturer-supplied module peak powers at STC for a similarly located and configured a-Si PV array should be derated by factors of approximately of 0.83 and 0.78 for summer and winter operation, respectively.

  7. Technical evaluation of a USSC Integrated/Direct Mount PV Roofing Module system at NREL

    NASA Astrophysics Data System (ADS)

    Strand, Troy; Hansen, Robert; Mrig, Laxmi

    1995-05-01

    The results of a 16 month technical evaluation performed on a nominal 1 kW(sub ac) utility-interconnect amorphous silicon PV system deployed at the National Renewable Energy Laboratory's PV outdoor test site are given here. The system employs 64 prototype United Solar Systems Corp. Integrated/Direct Mount PV Roofing Modules mounted on simulated attic/roof structures. In this paper we show that the PV array fill factor has been relatively stable with respect to time and that the seasonal variations in performance can be largely attributed to seasonal variations in current. We also show that in determining the summer and winter ac power output, the summation of the manufacturer-supplied module peak powers at STC for a similarly located and configured a-Si PV array should be derated by factors of approximately of 0.83 and 0.78 for summer and winter operation, respectively.

  8. Technical evaluation of a USSC integrated/direct mount PV roofing module system at NREL

    NASA Astrophysics Data System (ADS)

    Strand, T.; Hansen, R.; Mrig, L.

    1996-01-01

    The results of a 16 month technical evaluation performed on a nominal 1 kWac utility-interconnect amorphous silicon PV system deployed at the National Renewable Energy Laboratory's PV outdoor test site are given here. The system employs 64 prototype United Solar Systems Corp. Integrated/Direct Mount PV Roofing Molecules mounted on simulated attic/roof structures. In this paper we show that the PV array fill factor has been relatively stable with respect to time and that the seasonal variations in performance can be largely attributed to seasonal variations in current. We also show that in determining the summer and winter ac power output, the summation of the manufacturer-supplied module peak powers at STC for a similarly located and configured a-Si PV array should be derated by factors of approximately of 0.83 and 0.78 for summer and winter operation, respectively.

  9. Photovoltaic roofing tile systems

    NASA Astrophysics Data System (ADS)

    Melchior, B.

    The integration of photovoltaic (PV) systems in architecture is discussed. A PV-solar roofing tile system with polymer concrete base; PV-roofing tile with elastomer frame profiles and aluminum profile frames; contact technique; and solar cell modules measuring technique are described. Field tests at several places were conducted on the solar generator, electric current behavior, battery station, electric installation, power conditioner, solar measuring system with magnetic bubble memory technique, data transmission via telephone modems, and data processing system. The very favorable response to the PV-compact system proves the commercial possibilities of photovoltaic integration in architecture.

  10. Automatic Roof Plane Detection and Analysis in Airborne Lidar Point Clouds for Solar Potential Assessment

    PubMed Central

    Jochem, Andreas; Höfle, Bernhard; Rutzinger, Martin; Pfeifer, Norbert

    2009-01-01

    A relative height threshold is defined to separate potential roof points from the point cloud, followed by a segmentation of these points into homogeneous areas fulfilling the defined constraints of roof planes. The normal vector of each laser point is an excellent feature to decompose the point cloud into segments describing planar patches. An object-based error assessment is performed to determine the accuracy of the presented classification. It results in 94.4% completeness and 88.4% correctness. Once all roof planes are detected in the 3D point cloud, solar potential analysis is performed for each point. Shadowing effects of nearby objects are taken into account by calculating the horizon of each point within the point cloud. Effects of cloud cover are also considered by using data from a nearby meteorological station. As a result the annual sum of the direct and diffuse radiation for each roof plane is derived. The presented method uses the full 3D information for both feature extraction and solar potential analysis, which offers a number of new applications in fields where natural processes are influenced by the incoming solar radiation (e.g., evapotranspiration, distribution of permafrost). The presented method detected fully automatically a subset of 809 out of 1,071 roof planes where the arithmetic mean of the annual incoming solar radiation is more than 700 kWh/m2. PMID:22346695

  11. Barrel-shaped solar roofing element and method for its assembly

    SciTech Connect

    Allegro, J.

    1991-06-11

    This patent describes a solar roofing system. It comprises a set of shingle comprising lower and upper flat plastic sheet members of extruded plastic spaced apart and sealed together to form fluid flow paths forming solar energy conversion means, the upper sheet of which is transparent to solar energy, interconnecting and overlapping structure for joining shingles together including structure for nailing through overlapped shingles into a roof surface, and means for interconnecting the solar energy conversion means comprising a flow path between the lower and upper plastic sheets for circulation of a liquid that may store heat when subjected to solar energy from a plurality of the shingles into a network for collecting accumulated solar energy.

  12. 75 FR 7029 - Notice of Availability of the Final Environmental Assessment for Solar Roof Project

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-16

    ... Geological Survey Notice of Availability of the Final Environmental Assessment for Solar Roof Project AGENCY: United States Geological Survey. ACTION: Notice of availability. SUMMARY: In accordance with the National... Project and by this notice is announcing its availability. DATES: The USGS publishes this Notice in...

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

    SciTech Connect

    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.

  14. Photovoltaic Roofs

    NASA Technical Reports Server (NTRS)

    Drummond, R. W., Jr.; Shepard, N. F., Jr.

    1984-01-01

    Solar cells perform two functions: waterproofing roof and generating electricity. Sections through horizontal and slanting joints show overlapping modules sealed by L-section rubber strips and side-by-side modules sealed by P-section strips. Water seeping through seals of slanting joints drains along channels. Rooftop photovoltaic array used watertight south facing roof, replacing shingles, tar, and gravel. Concept reduces cost of residential solar-cell array.

  15. Barrel-shaped solar roofing element and method for its manufacture

    SciTech Connect

    Allegro, J.

    1990-09-04

    This patent describes a solar roofing element system. It comprises: a curved panel portion of plastic formed by injection molding having a liquid passageway therethrough and presenting an outer surface adapted for receiving solar energy constructed generally of insulative material having a relatively thin dimension between the outer surface and the liquid passageway comprising a tapered barrel-shaped construction with a smaller substantially closed end of conic section opposed to a larger substantially closed end of conic section, and means for connecting the passageway extending throughout the panel to a solar system for processing heat exchange fluid.

  16. City of Grand Rapids Building Solar Roof Demonstration

    SciTech Connect

    DeClercq, Mark; Martinez, Imelda

    2012-08-31

    Grand Rapids, Michigan is striving to reduce it environmental footprint. The municipal government organization has established environmental sustainability policies with the goal of securing 100% of its energy from renewable sources by 2020. This report describes the process by which the City of Grand Rapids evaluated, selected and installed solar panels on the Water/Environmental Services Building. The solar panels are the first to be placed on a municipal building. Its new power monitoring system provides output data to assess energy efficiency and utilization. It is expected to generate enough clean solar energy to power 25 percent of the building. The benefit to the public includes the economic savings from reduced operational costs for the building; an improved environmentally sustainable area in which to live and work; and increased knowledge about the use of solar energy. It will serve as a model for future energy saving applications.

  17. Refined estimation of solar energy potential on roof areas using decision trees on CityGML-data

    NASA Astrophysics Data System (ADS)

    Baumanns, K.; Löwner, M.-O.

    2009-04-01

    We present a decision tree for a refined solar energy plant potential estimation on roof areas using the exchange format CityGML. Compared to raster datasets CityGML-data holds geometric and semantic information of buildings and roof areas in more detail. In addition to shadowing effects ownership structures and lifetime of roof areas can be incorporated into the valuation. Since the Renewable Energy Sources Act came into force in Germany in 2000, private house owners and municipals raise attention to the production of green electricity. At this the return on invest depends on the statutory price per Watt, the initial costs of the solar energy plant, its lifetime, and the real production of this installation. The latter depends on the radiation that is obtained from and the size of the solar energy plant. In this context the exposition and slope of the roof area is as important as building parts like chimneys or dormers that might shadow parts of the roof. Knowing the controlling factors a decision tree can be created to support a beneficial deployment of a solar energy plant. Also sufficient data has to be available. Airborne raster datasets can only support a coarse estimation of the solar energy potential of roof areas. While they carry no semantically information, even roof installations are hardly to identify. CityGML as an Open Geospatial Consortium standard is an interoperable exchange data format for virtual 3-dimensional Cities. Based on international standards it holds the aforementioned geometric properties as well as semantically information. In Germany many Cities are on the way to provide CityGML dataset, e. g. Berlin. Here we present a decision tree that incorporates geometrically as well as semantically demands for a refined estimation of the solar energy potential on roof areas. Based on CityGML's attribute lists we consider geometries of roofs and roof installations as well as global radiation which can be derived e. g. from the European Solar Radiation Atlas. After identifying the shadow free area of the roof we recognize manufacturer dependent device sizes as well as lifetime of the building. While more and more CityGML data will be available in future or approach is a valuable contribution for decision makers and private households to estimate the return on invest of solar energy plants.

  18. Wind and solar energy resources on the 'Roof of the World'

    NASA Astrophysics Data System (ADS)

    Zandler, Harald; Morche, Thomas; Samimi, Cyrus

    2015-04-01

    The Eastern Pamirs of Tajikistan, often referred to as 'Roof of the World', are an arid high mountain plateau characterized by severe energy poverty that may have great potential for renewable energy resources due to the prevailing natural conditions. The lack of energetic infrastructure makes the region a prime target for decentralized integration of wind and solar power. However, up to date no scientific attempt to assess the regional potential of these resources has been carried out. In this context, it is particularly important to evaluate if wind and solar energy are able to provide enough power to generate thermal energy, as other thermal energy carriers are scarce or unavailable and the existing alternative, local harvest of dwarf shrubs, is unsustainable due to the slow regeneration in this environment. Therefore, this study examines the feasibility of using wind and solar energy as thermal energy sources. Financial frame conditions were set on a maximum amount of five million Euros. This sum provides a realistic scenario as it is based on the current budget of the KfW development bank to finance the modernization of the local hydropower plant in the regions only city, Murghab, with about 1500 households. The basis for resource assessment is data of four climate stations, erected for this purpose in 2012, where wind speed, wind direction, global radiation and temperature are measured at a half hourly interval. These measurements confirm the expectation of a large photovoltaic potential and high panel efficiency with up to 84 percent of extraterrestrial radiation reaching the surface and only 16 hours of temperatures above 25°C were measured in two years at the village stations on average. As these observations are only point measurements, radiation data and the ASTER GDEM was used to train a GIS based solar radiation model to spatially extrapolate incoming radiation. With mean validation errors ranging from 5% in July (minimum) to 15% in December (maximum) the extrapolation showed sufficient modeling performance to create the first solar atlas of the Eastern Pamirs. This solar atlas, adapted to optimal panel inclination using 5000 random points, was used to compute expected electricity amounts for two scenarios: one for decentralized small scale implementation and one for a larger scale photovoltaic (PV) power plant. Based on the month with the minimum incoming radiation and the expected energy demand for cooking, the cost for the required infrastructure was assessed. The results showed that an implementation of a PV power plant in Murghab would generate enough power for basic cooking within the estimated budget in winter. In summer the power plant would deliver at least as much energy as the planned hydropower plant if latter would continuously deliver its anticipated peak power. The decentralized scenario for a village with 210 households without existing energy grid resulted in higher investment costs of about 8,000 € per household to meet basic cooking demands in winter. Wind energy potential was assessed based on local wind measurements and an assumed installation of small scale wind turbines. Short time scale comparison of wind and solar resources showed that they mainly occur simultaneously and positive synergy effects are negligible. Furthermore, the financial analysis resulted in significantly higher cost for wind energy even in favorable locations making this resource less important for the region. Our results suggest that solar energy could make a substantial contribution to sustainable energy supply and to alleviate energy poverty and environmental degradation in the Eastern Pamirs of Tajikistan.

  19. SolarTile: A rooftop integrated photovoltaic system. Phase 1, final report

    SciTech Connect

    1998-03-26

    AstroPower, Royal Group Technologies, and Solar Design Associates are jointly developing an integrated photovoltaic roofing system for residential and light commercial building applications. This family of products will rely heavily on the technological development of a roofing tile made from recycled plastic and innovative module fabrication and encapsulation processes in conjunction with an advanced Silicon-Film{trademark} solar cell product. This solar power generating roofing product is presently being referred to as the SolarTile. A conceptual drawing of the solar roofing tile is shown. The SolarTile will be integrated with non-solar tiles in a single roof installation permitting ease of assembly and the ability to use conventional roofing techniques at ridges, valleys, and eaves. The Phase 1 effort included tasks aimed at the development of the proposed product concept; product manufacturing or fabrication, and installation cost estimates; business planning; and a market assessment of the proposed product, including target selling prices, target market sectors, size estimates for each market sector, and planned distribution mechanisms for market penetration. Technical goals as stated in the Phase 1 proposal and relevant progress are reported.

  20. Citywide Impacts of Cool Roof and Rooftop Solar Photovoltaic Deployment on Near-Surface Air Temperature and Cooling Energy Demand

    NASA Astrophysics Data System (ADS)

    Salamanca, F.; Georgescu, M.; Mahalov, A.; Moustaoui, M.; Martilli, A.

    2016-04-01

    Assessment of mitigation strategies that combat global warming, urban heat islands (UHIs), and urban energy demand can be crucial for urban planners and energy providers, especially for hot, semi-arid urban environments where summertime cooling demands are excessive. Within this context, summertime regional impacts of cool roof and rooftop solar photovoltaic deployment on near-surface air temperature and cooling energy demand are examined for the two major USA cities of Arizona: Phoenix and Tucson. A detailed physics-based parametrization of solar photovoltaic panels is developed and implemented in a multilayer building energy model that is fully coupled to the Weather Research and Forecasting mesoscale numerical model. We conduct a suite of sensitivity experiments (with different coverage rates of cool roof and rooftop solar photovoltaic deployment) for a 10-day clear-sky extreme heat period over the Phoenix and Tucson metropolitan areas at high spatial resolution (1-km horizontal grid spacing). Results show that deployment of cool roofs and rooftop solar photovoltaic panels reduce near-surface air temperature across the diurnal cycle and decrease daily citywide cooling energy demand. During the day, cool roofs are more effective at cooling than rooftop solar photovoltaic systems, but during the night, solar panels are more efficient at reducing the UHI effect. For the maximum coverage rate deployment, cool roofs reduced daily citywide cooling energy demand by 13-14 %, while rooftop solar photovoltaic panels by 8-11 % (without considering the additional savings derived from their electricity production). The results presented here demonstrate that deployment of both roofing technologies have multiple benefits for the urban environment, while solar photovoltaic panels add additional value because they reduce the dependence on fossil fuel consumption for electricity generation.

  1. GPU-based roofs' solar potential estimation using LiDAR data

    NASA Astrophysics Data System (ADS)

    Lukač, Niko; Žalik, Borut

    2013-03-01

    Solar potential estimation using LiDAR data is an efficient approach for finding suitable roofs for photovoltaic systems' installations. As the amount of LiDAR data increases, the non-parallel methods take considerable time to accurately estimate the solar potential. Although supercomputing provides a possible solution, it is still too expensive and thus infeasible for general usage. Fortunately, the recent graphics processing units (GPUs) can now be utilized to ensure fast computations. This paper proposes a novel method for fast solar potential estimation using GPU-based CUDA technology. This method employs LiDAR data, irradiance measurements, multiresolutional shadowing from solid objects, and heuristic shadowing from vegetation. Experimental results demonstrate the method's effectiveness, in comparison with a multi-core CPU-based approach.

  2. Sleep Medicine Care Under One Roof: A Proposed Model for Integrating Dentistry and Medicine

    PubMed Central

    Sharma, Sunil; Essick, Greg; Schwartz, David; Aronsky, Amy J.

    2013-01-01

    Integrating oral appliance therapy into the delivery of care for sleeprelated breathing disorders has been a challenge for dental and medical professionals alike. We review the difficulties that have been faced and propose a multidisciplinary care delivery model that integrates dental sleep medicine and sleep medicine under the same roof with educational and research components. The model promises to offer distinct advantages to improved patient care, continuity of treatment, and the central coordination of clinical and insurance-related benefits. Citation: Sharma S; Essick G; Schwartz D; Aronsky AJ. Sleep medicine care under one roof: a proposed model for integrating dentistry and medicine. J Clin Sleep Med 2013;9(8):827-833. PMID:23946715

  3. An Integrative Analysis of an Extensive Green Roof System: A Case Study of the Schleman Green Roof

    NASA Astrophysics Data System (ADS)

    Hoover, F.; Bowling, L. C.

    2013-12-01

    In urban environments where populations continue to rise, the need for affective stormwater management and runoff control methods is ever prevalent. Increased population growth and city expansion means greater impervious surfaces and higher rates of stormwater runoff. In well-established cities, this proves particularly difficult due to a constraining built environment and limited pervious spaces, even in cities as small as 40,000 residents. Work to reduce runoff in combined sewer systems (CSS) and municipal separated storm sewer systems (MS4) by use of best-management practices is one route currently under investigation. The Purdue University campus is making efforts to reduce their impact on the West Lafayette CSS and MS4. Green roofs are one management practice being used for runoff mitigation. Specifically, Schleman Hall, an administrative student affairs building, has a small green roof located on the second floor installed in 2008. In cooperation with Purdue Physical Facilities, monitoring and analysis for the Schleman extensive green roof at Purdue University was performed from June 2012 to December 2012. The objective was to determine the stormwater retention, output water quality and net present value for the 165 m2 roof. The results from the water balance analysis revealed retention rates on average of 58% of precipitation per rain event, where retention included soil moisture, evaporation and detention/depression storage. The water quality metrics tested were Nitrate-Nitrite (NO2-NO3), Orthophosphate (PO4), Ammonia-Ammonium ion (NH3-NH4), Sulfate (SO4), total suspended solids (TSS) and pH. The pollutant concentration and load results varied, but the pH levels from precipitation increased in all samples after passing through the substrate. SO4 and PO4 results yielded higher concentrations and loads in the green roof output than the control output and precipitation, while NO2-NO3 and NH3-NH4 yielded concentrations and loads that were reduced by the green roof when compared to the control output and precipitation. The green roof caused a decrease in the energy load (KJ/hr) needed to maintain a near constant temperature in the conference room situated below the green roof. These results combined with potential carbon pricing, stormwater fees and an installment grant resulted in a net present value of $32,350 for the Schleman Hall roof. The analysis demonstrates potential benefits, but highlights the need for further research that involves a more detailed simulation and the valuing of ecosystem services offered by the green roof.

  4. Cloud-Aerosol Drivers of Reflective Roof and Solar Power Potential Benefits Across Selected Indian Cities

    NASA Astrophysics Data System (ADS)

    Millstein, D.; Fischer, M. L.

    2013-12-01

    Application of reflective roof surfaces is an adaptive strategy for sustainable warm-climate human environments that can improve human comfort for un-conditioned buildings, energy consumption for conditioned buildings, the urban heat island effect, and potentially net radiation absorbed by the earth. Here, we evaluate the (1) potential radiative benefits of installing cool roofs and (2) incoming surface radiation available for solar power generation across selected Indian cities using a combination of satellite data (MODIS and MERRA) and a radiative transfer model (RRTMG). The radiative transfer model was run multiple times at each time step and location in order to separate the effects of clouds and aerosols on top of the atmosphere outgoing shortwave radiation reflected from roofs and on bottom of the atmosphere incoming shortwave radiation available for solar power generation. Modeled downwelling shortwave radiation at the surface was first validated against measurements obtained from urban rooftops during the 9-month (June, 2011-March, 2012) a joint Indian-US Ganges Valley Aerosol Experiment (GVAX) campaign. Results show that model bias at two Indian cities, Nainital (-4.2% average midday bias) and Pantnagar (0.5% average midday bias) was small compared to the radiative benefit obtained from a typical increase in surface reflectance (e.g., 0.3-0.6). Although both cities are located in the northern state of Uttarakhand, differences in terrain type, pollution burdens and cloudiness allow for validation of the model across a wide range of conditions. For example, Nainital is located in complex terrain at an altitude of ~2,000 meters near the Himalayan Mountains while Pantnagar is located in a flat plain at an altitude of ~300 meters. Pantnagar had a larger aerosol burden than Nainital as the average aerosol optical depth at Pantnagar (0.47) was larger than Nainital (0.33). Nainital was cloudier, with clouds observed on 62% of the days during the validation period while clouds were observed in Pantnagar on only 47% of the days. We then extend the model analysis to major Indian cities including New Delhi, Mumbai, Kolkata, and Bangalore. Preliminary results indicate that total (anthropogenic and natural) aerosols reduce the additional top of the atmosphere outgoing radiation from the installation of reflective roofs by an average of 45-110 W m-2 at midday, with the high end of the range set at New Dehli and the low end of the range set at Nainital. Similarly, aerosols reduce total incoming surface radiation by 61-150 W m-2, hence reducing potential solar power generation by up to 25% at some locations depending on the utilization of direct vs. diffuse solar energy. Ongoing analysis will evaluate inter-annual trends and variation in cloud and aerosol effects along with spatial variation across each selected city, and 1st order estimates of the potential improvements to radiative benefit and solar power generation from improvements to air quality. The authors note that the methods employed in this work to estimate radiative benefits from air quality changes assume constant cloud fields and do not account for any aerosol-cloud indirect effects or effects from land-use change (i.e. increased surface albedo from wide-scale adoption of reflective roofs).

  5. Interdisciplinary design study of a high-rise integrated roof wind energy system

    NASA Astrophysics Data System (ADS)

    Dekker, R. W. A.; Ferraro, R. M.; Suma, A. B.; Moonen, S. P. G.

    2012-10-01

    Today's market in micro-wind turbines is in constant development introducing more efficient solutions for the future. Besides the private use of tower supported turbines, opportunities to integrate wind turbines in the built environment arise. The Integrated Roof Wind Energy System (IRWES) presented in this work is a modular roof structure integrated on top of existing or new buildings. IRWES is build up by an axial array of skewed shaped funnels used for both wind inlet and outlet. This inventive use of shape and geometry leads to a converging air capturing inlet to create high wind mass flow and velocity toward a Vertical Axis Wind Turbine (VAWT) in the center-top of the roof unit for the generation of a relatively high amount of energy. The scope of this research aims to make an optimized structural design of IRWES to be placed on top of the Vertigo building in Eindhoven; analysis of the structural performance; and impact to the existing structure by means of Finite Element Modeling (FEM). Results show that the obvious impact of wind pressure to the structural design is easily supported in different configurations of fairly simple lightweight structures. In particular, the weight addition to existing buildings remains minimal.

  6. Integrated solar heating unit

    SciTech Connect

    Larkin, W.J.

    1987-01-20

    This patent describes an integral solar heating unit with an integral solar collector and hot water storage system, the unit comprising: (a) a housing; (b) a flat plate solar collector panel mounted in the housing and having a generally horizontal upper edge and an uninsulated, open back surface; (c) a cylindrical hot water tank operatively connected to the solar collector panel and mounted in the housing generally parallel to and adjacent to the upper edge; (d) the housing comprising a hood around the tank a pair of side skirts extending down at the sides of the panel. The hood and side skirts terminate at lower edges which together substantially define a plane such that upon placing the heating unit on a generally planar surface, the housing substantially encapsulates the collector panel and hot water tank in a substantially enclosed air space; (e) the collector including longitudinally extended U-shaped collector tubes and a glazed window to pass radiation through to the collector tubes, and a first cold water manifold connected to the tubes for delivering fresh water thereto and a second hot water manifold connected to the tubes to remove heated water therefrom. The manifolds are adjacent and at least somewhat above and in direct thermal contact with the tank; and, (f) the skirts and hood lapping around the collector panel, exposing only the glazed window, such that everything else in the heating unit is enclosed by the housing such that heat emanating from the uninsulated, open back face of the collector and tank is captured and retained by the housing to warm the manifolds.

  7. Roof-top solar energy potential under performance-based building energy codes: The case of Spain

    SciTech Connect

    Izquierdo, Salvador; Montanes, Carlos; Dopazo, Cesar; Fueyo, Norberto

    2011-01-15

    The quantification at regional level of the amount of energy (for thermal uses and for electricity) that can be generated by using solar systems in buildings is hindered by the availability of data for roof area estimation. In this note, we build on an existing geo-referenced method for determining available roof area for solar facilities in Spain to produce a quantitative picture of the likely limits of roof-top solar energy. The installation of solar hot water systems (SHWS) and photovoltaic systems (PV) is considered. After satisfying up to 70% (if possible) of the service hot water demand in every municipality, PV systems are installed in the remaining roof area. Results show that, applying this performance-based criterion, SHWS would contribute up to 1662 ktoe/y of primary energy (or 68.5% of the total thermal-energy demand for service hot water), while PV systems would provide 10 T W h/y of electricity (or 4.0% of the total electricity demand). (author)

  8. Integrated Modelling and Performance Analysis of Green Roof Technologies in Urban Environments

    NASA Astrophysics Data System (ADS)

    Liu, Xi; Mijic, Ana; Maksimovic, Cedo

    2014-05-01

    As a result of the changing global climate and increase in urbanisation, the behaviour of the urban environment has been significantly altered, causing an increase in both the frequency of extreme weather events, such as flooding and drought, and also the associated costs. Moreover, uncontrolled or inadequately planned urbanisation can exacerbate the damage. The Blue-Green Dream (BGD) project therefore develops a series of components for urban areas that link urban vegetated areas (green infrastructure) with existing urban water (blue) systems, which will enhance the synergy of urban blue and green systems and provide effective, multifunctional BGD solutions to support urban adaptation to future climatic changes. Coupled with new urban water management technologies and engineering, multifunctional benefits can be gained. Some of the technologies associated with BGD solutions include green roofs, swales that might deal with runoff more effectively and urban river restoration that can produce benefits similar to those produced from sustainable urban drainage systems (SUDS). For effective implementation of these technologies, however, appropriate tools and methodologies for designing and modelling BGD solutions are required to be embedded within urban drainage models. Although several software packages are available for modelling urban drainage, the way in which green roofs and other BGD solutions are integrated into these models is not yet fully developed and documented. This study develops a physically based mass and energy balance model to monitor, test and quantitatively evaluate green roof technology for integrated BGD solutions. The assessment of environmental benefits will be limited to three aspects: (1) reduction of the total runoff volume, (2) delay in the initiation of runoff, and (3) reduction of building energy consumption, rather than water quality, visual, social or economic impacts. This physically based model represents water and heat dynamics in a layered soil profile covered with vegetation which can be used to simulate the physical behaviour of different green roof systems in response to rainfall under various climatic conditions. Because it is a physically based model, this model could be generalised to other atmosphere-plant-soil systems. The validity of this mass and energy balance approach will be demonstrated by comparing its outcomes with observations from a green roof experimental site in London, UK.

  9. Effects of soiling and cleaning on the reflectance and solar heat gain of a light-colored roofing membrane

    NASA Astrophysics Data System (ADS)

    Levinson, Ronnen; Berdahl, Paul; Asefaw Berhe, Asmeret; Akbari, Hashem

    A roof with high solar reflectance and high thermal emittance (e.g., a white roof) stays cool in the sun, reducing cooling power demand in a conditioned building and increasing summertime comfort in an unconditioned building. The high initial solar reflectance of a white membrane roof (circa 0.8) can be lowered by deposition of soot, dust, and/or biomass (e.g., fungi or algae) to about 0.6; degraded solar reflectances range from 0.3 to 0.8, depending on exposure. We investigate the effects of soiling and cleaning on the solar spectral reflectances and solar absorptances of 15 initially white or light-gray polyvinyl chloride membrane samples taken from roofs across the United States. Black carbon and organic carbon were the two identifiable strongly absorbing contaminants on the membranes. Wiping was effective at removing black carbon, and less so at removing organic carbon. Rinsing and/or washing removed nearly all of the remaining soil layer, with the exception of (a) thin layers of organic carbon and (b) isolated dark spots of biomass. Bleach was required to clear these last two features. At the most soiled location on each membrane, the ratio of solar reflectance to unsoiled solar reflectance (a measure of cleanliness) ranged from 0.41 to 0.89 for the soiled samples; 0.53 to 0.95 for the wiped samples; 0.74 to 0.98 for the rinsed samples; 0.79 to 1.00 for the washed samples; and 0.94 to 1.02 for the bleached samples. However, the influences of membrane soiling and cleaning on roof heat gain are better gauged by fractional variations in solar absorptance. Solar absorptance ratios (indicating solar heat gain relative to that of an unsoiled membrane) ranged from 1.4 to 3.5 for the soiled samples; 1.1 to 3.1 for the wiped samples; 1.0 to 2.0 for the rinsed samples; 1.0 to 1.9 for the washed samples; and 0.9 to 1.3 for the bleached samples.

  10. Become One In A Million: Partnership Updates. Million Solar Roofs and Interstate Renewable Energy Council Annual Meeting, Washington, D.C., October 2005

    SciTech Connect

    Tombari, C.

    2005-09-01

    The U.S. Department of Energy's Million Solar Roofs Initiative (MSR) is a unique public-private partnership aimed at overcoming market barriers for photovoltaics (PV), solar water heating, transpired solar collectors, solar space heating and cooling, and pool heating. This report contains annual progress reports from 866 partners across the United States.

  11. Soiling of building envelope surfaces and its effect on solar reflectance. Part I: Analysis of roofing product databases

    SciTech Connect

    Sleiman, Mohamad; Ban-Weiss, George; Gilbert, Haley E.; François, David; Berdahl, Paul; Kirchstetter, Thomas W.; Destaillats, Hugo; Levinson, Ronnen

    2011-12-01

    The use of highly reflective “cool” roofing materials can decrease demand for air conditioning, mitigate the urban heat island effect, and potentially slow global warming. However, initially high roof solar reflectance can be degraded by natural soiling and weathering processes. We evaluated solar reflectance losses after three years of natural exposure reported in two separate databases: the Rated Products Directory of the US Cool Roof Rating Council (CRRC) and information reported by manufacturers to the US Environmental Protection Agency (EPA)’s ENERGY STAR® rating program. Many product ratings were culled because they were duplicative (within a database) or not measured. A second, site-resolved version of the CRRC dataset was created by transcribing from paper records the site-specific measurements of aged solar reflectance in Florida, Arizona and Ohio. Products with high initial solar reflectance tended to lose reflectance, while those with very low initial solar reflectance tended to become more reflective as they aged. Within the site-resolved CRRC database, absolute solar reflectance losses for samples of medium-to-high initial solar reflectance were 2 - 3 times greater in Florida (hot and humid) than in Arizona (hot and dry); losses in Ohio (temperate but polluted) were intermediate. Disaggregating results by product type, factory-applied coating, field-applied coating, metal, modified bitumen, shingle, singleply membrane and tile, revealed that absolute solar reflectance losses were largest for fieldapplied coating, modified bitumen and single-ply membrane products, and smallest for factoryapplied coating and metal products.The 2008 Title 24 provisional aged solar reflectance formula overpredicts the measured aged solar reflectance of 0% to 30% of each product type in the culled public CRRC database. The rate of overprediction was greatest for field-applied coating and single-ply membrane products and least for factory-applied coating, shingle, and metal products. New product-specific formulas can be used to estimate provisional aged solar reflectance from initial solar reflectance pending measurement of aged solar reflectance. The appropriate value of soiling resistance varies by product type and is selected to attain some desired overprediction rate for the formula. The correlations for shingle products presented in this paper should not be used to predict aged solar reflectance or estimate provisional aged solar reflectance because the data set is too small and too limited in range of initial solar reflectance.

  12. Soiling of building envelope surfaces and its effect on solar reflectance. Part I: Analysis of roofing product databases

    DOE PAGESBeta

    Sleiman, Mohamad; Ban-Weiss, George; Gilbert, Haley E.; François, David; Berdahl, Paul; Kirchstetter, Thomas W.; Destaillats, Hugo; Levinson, Ronnen

    2011-12-01

    The use of highly reflective “cool” roofing materials can decrease demand for air conditioning, mitigate the urban heat island effect, and potentially slow global warming. However, initially high roof solar reflectance can be degraded by natural soiling and weathering processes. We evaluated solar reflectance losses after three years of natural exposure reported in two separate databases: the Rated Products Directory of the US Cool Roof Rating Council (CRRC) and information reported by manufacturers to the US Environmental Protection Agency (EPA)’s ENERGY STAR® rating program. Many product ratings were culled because they were duplicative (within a database) or not measured. Amore » second, site-resolved version of the CRRC dataset was created by transcribing from paper records the site-specific measurements of aged solar reflectance in Florida, Arizona and Ohio. Products with high initial solar reflectance tended to lose reflectance, while those with very low initial solar reflectance tended to become more reflective as they aged. Within the site-resolved CRRC database, absolute solar reflectance losses for samples of medium-to-high initial solar reflectance were 2 - 3 times greater in Florida (hot and humid) than in Arizona (hot and dry); losses in Ohio (temperate but polluted) were intermediate. Disaggregating results by product type, factory-applied coating, field-applied coating, metal, modified bitumen, shingle, singleply membrane and tile, revealed that absolute solar reflectance losses were largest for fieldapplied coating, modified bitumen and single-ply membrane products, and smallest for factoryapplied coating and metal products.The 2008 Title 24 provisional aged solar reflectance formula overpredicts the measured aged solar reflectance of 0% to 30% of each product type in the culled public CRRC database. The rate of overprediction was greatest for field-applied coating and single-ply membrane products and least for factory-applied coating, shingle, and metal products. New product-specific formulas can be used to estimate provisional aged solar reflectance from initial solar reflectance pending measurement of aged solar reflectance. The appropriate value of soiling resistance varies by product type and is selected to attain some desired overprediction rate for the formula. The correlations for shingle products presented in this paper should not be used to predict aged solar reflectance or estimate provisional aged solar reflectance because the data set is too small and too limited in range of initial solar reflectance.« less

  13. Methods of Creating Solar-Reflective Nonwhite Surfaces and theirApplication to Residential Roofing Materials

    SciTech Connect

    Levinson, Ronnen; Berdahl, Paul; Akbari, Hashem; Miller, William; Joedicke, Ingo; Reilly, Joseph; Suzuki, Yoshi; Vondran, Michelle

    2005-05-24

    We describe methods for creating solar-reflective nonwhitesurfaces and their application to a wide variety of residential roofingmaterials, including metal, clay tile, concrete tile, wood, and asphaltshingle. Reflectance in the near-infrared (NIR) spectrum (0.7 2.5mu m) ismaximized by coloring a topcoatwith pigments that weakly absorb and(optionally) strongly backscatter NIR radiation, and adding anNIR-reflective basecoat (e.g., titanium dioxide white) if both thetopcoat and substrate weakly reflect NIR radiation. Coated steel andglazed clay tile roofing products achieved NIRreflectances of up to 0.50and 0.75, respectively, using only cool topcoats. Gray concrete tilesachieve NIR reflectances as high as 0.60 when thickly coated withNIR-scattering pigments, and could attain an NIR reflectances as high as0.85 by overlaying a titanium-dioxide basecoat with a topcoat colored byNIR-transparent organic pigments. Granule-surfaced asphalt shinglesachieved NIR reflectances as high as 0.45 when a cool color topcoat wasapplied over a thick white basecoat.

  14. COOL ROOF COATINGS INCORPORATING GLASS HOLLOW MICROSPHERES FOR IMPROVED SOLAR REFLECTANCE

    EPA Science Inventory

    Elastomeric cool-roof coatings can be applied to buildings to decrease heat gain, yielding energy savings and mitigating the urban heat island effect. Most cool-roof formulations are based on titanium dioxide (TiO2). While TiO2 and several TiO2

  15. COOL ROOF COATINGS INCORPORATING GLASS HOLLOW MICROSPHERES FOR IMPROVED SOLAR REFLECTANCE

    EPA Science Inventory

    Elastomeric cool-roof coatings can be applied to buildings to decrease heat gain, yielding energy savings and mitigating the “urban heat island” effect. Most cool-roof formulations are based on titanium dioxide (TiO2). While TiO2 and several TiO2

  16. Efficiency of a closed-coupled solar pasteurization system in treating roof harvested rainwater.

    PubMed

    Dobrowsky, P H; Carstens, M; De Villiers, J; Cloete, T E; Khan, W

    2015-12-01

    Many studies have concluded that roof harvested rainwater is susceptible to chemical and microbial contamination. The aim of the study was thus to conduct a preliminary investigation into the efficiency of a closed-coupled solar pasteurization system in reducing the microbiological load in harvested rainwater and to determine the change in chemical components after pasteurization. The temperature of the pasteurized tank water samples collected ranged from 55 to 57°C, 64 to 66°C, 72 to 74°C, 78 to 81°C and 90 to 91°C. Cations analyzed were within drinking water guidelines, with the exception of iron [195.59 μg/L (55°C)-170.1 μg/L (91°C)], aluminum [130.98 μg/L (78°C)], lead [12.81 μg/L (55°C)-13.2 μg/L (91°C)] and nickel [46.43 μg/L (55°C)-32.82 μg/L (78°C)], which were detected at levels above the respective guidelines in the pasteurized tank water samples. Indicator bacteria including, heterotrophic bacteria, Escherichia coli and total coliforms were reduced to below the detection limit at pasteurization temperatures of 72°C and above. However, with the use of molecular techniques Yersinia spp., Legionella spp. and Pseudomonas spp. were detected in tank water samples pasteurized at temperatures greater than 72°C. The viability of the bacteria detected in this study at the higher temperature ranges should thus be assessed before pasteurized harvested rainwater is used as a potable water source. In addition, it is recommended that the storage tank of the pasteurization system be constructed from an alternative material, other than stainless steel, in order for a closed-coupled pasteurization system to be implemented and produce large quantities of potable water from roof harvested rainwater. PMID:26218559

  17. Integrated solar collector

    DOEpatents

    Tchernev, Dimiter I.

    1985-01-01

    A solar collector having a copper panel in a contiguous space relationship with a condenser-evaporator heat exchanger located under the panel, the panel having a honeycomb-like structure on its interior defining individual cells which are filled with zeolite loaded, in its adsorbed condition, with 18 to 20% by weight of water. The interior of the panel and heat exchanger are maintained at subatmospheric pressure of about 0.1 to 1 psia. The panel and heat exchanger are insulated on their lateral sides and bottoms and on the top of the heat exchange. The panel has a black coating on its top which is exposed to and absorbs solar energy. Surrounding the insulation (which supports the panel) is an extruded aluminum framework which supports a pair of spaced-apart glass panels above the solar panel. Water in conduits from a system for heating or cooling or both is connected to flow into an inlet and discharge from outlet of a finned coil received within the heat exchanger. The collector panel provides heat during the day through desorption and condensing of water vapor from the heated solar panel in the heat exchanger and cools at night by the re-adsorption of the water vapor from the heat exchanger which lowers the absolute pressure within the system and cools the heat exchange coils by evaporation.

  18. Simulated Impact of Roof Solar Absorptance, Attic, and DuctInsulation, and Climate on Cooling and Heating Energy Use inSingle-Family Resi dential Buildings

    SciTech Connect

    Akbari, H.; Konopacki, S.

    1998-10-26

    This report summarizes a comparative analysis of the impact of roof surface solar absorptance, attic, and duct insulation on simulated residential annual cooling and heating energy use in sixteen sunbelt climates. These locations cover a wide range of climates where cool roofs are expected to save energy and money, and are areas with high growth rates in new residential construction. The residences are single-story, single-family of new construction with either a gas furnace or an electric heat pump, and with ducts in the attic OT conditioned zone. The objective is to demonstrate that a residence with a cool roof could utilize a lower level of attic insulation than one with a dark roof with a zero net change in the annual energy bill. Annual energy use is simulated with DOE-2. lE, which was adapted with a validated residential duct-attic function, for dark and cool roofs and eleven attic insulation R-values ranging from 1 through 60. Analysis of the simulated energy savings from the light-colored roofs show that the savings can be transformed into an equivalent reduction in the level of attic insulation. Reductions in R-value are observed in varying degrees for residences with both gas and electric heat, all duct configurations, and all climates. In some cooling dominated climates there are cases where a cool roof could be implemented without attic insulation.

  19. Soiling of building envelope surfaces and its effect on solar reflectance - Part II: Development of an accelerate aging method for roofing materials

    SciTech Connect

    Sleiman, Mohamad; Kirchstetter, Thomas W.; Berdahl, Paul; Gilbert, Haley; Quelen, Sarah; Marlot, Lea; Preble, Chelsea; Chen, Sharon; Montalbano, Amadine; Rosseler, Olivier; Akbari, Hashem; Levinson, Ronnen; Destaillats, Hugo

    2013-11-18

    Highly reflective roofs can decrease the energy required for building air conditioning, help mitigate the urban heat island effect, and slow global warming. However, these benefits are diminished by soiling and weathering processes that reduce the solar reflectance of most roofing materials. Soiling results from the deposition of atmospheric particulate matter and the growth of microorganisms, each of which absorb sunlight. Weathering of materials occurs with exposure to water, sunlight, and high temperatures. This study developed an accelerated aging method that incorporates features of soiling and weathering. The method sprays a calibrated aqueous soiling mixture of dust minerals, black carbon, humic acid, and salts onto preconditioned coupons of roofing materials, then subjects the soiled coupons to cycles of ultraviolet radiation, heat and water in a commercial weatherometer. Three soiling mixtures were optimized to reproduce the site-specific solar spectral reflectance features of roofing products exposed for 3 years in a hot and humid climate (Miami, Florida); a hot and dry climate (Phoenix, Arizona); and a polluted atmosphere in a temperate climate (Cleveland, Ohio). A fourth mixture was designed to reproduce the three-site average values of solar reflectance and thermal emittance attained after 3 years of natural exposure, which the Cool Roof Rating Council (CRRC) uses to rate roofing products sold in the US. This accelerated aging method was applied to 25 products?single ply membranes, factory and field applied coatings, tiles, modified bitumen cap sheets, and asphalt shingles?and reproduced in 3 days the CRRC's 3-year aged values of solar reflectance. This accelerated aging method can be used to speed the evaluation and rating of new cool roofing materials.

  20. MUNI Ways and Structures Building Integrated Solar Membrane Project

    SciTech Connect

    Smith, Randall

    2014-07-03

    The initial goal of the MUNI Ways and Structures Building Integrated Solar Membrane Installation Project was for the City and County of San Francisco (CCSF) to gain experience using the integrated higher efficiency solar photovoltaic (PV) single-ply membrane product, as it differs from the conventional, low efficiency, thin-film PV products, to determine the feasibility of success of larger deployment. As several of CCSF’s municipal rooftops are constrained with respect to weight restrictions, staff of the Energy Generation Group of the San Francisco Public Utilities Commission (SFPUC) proposed to install a solar PV system using single-ply membrane The installation of the 100 kW (DC-STC) lightweight photo voltaic (PV) system at the MUNI Ways and Structures Center (700 Pennsylvania Ave., San Francisco) is a continuation of the commitment of the City and County of San Francisco (CCSF) to increase the pace of municipal solar development, and serve its municipal facilities with clean renewable energy. The fourteen (14) solar photovoltaic systems that have already been installed at CCSF municipal facilities are assisting in the reduction of fossil-fuel use, and reduction of greenhouse gases from fossil combustion. The MUNI Ways & Structures Center roof has a relatively low weight-bearing capacity (3.25 pounds per square foot) and use of traditional crystalline panels was therefore rejected. Consequently it was decided to use the best available highest efficiency Building-Integrated PV (BIPV) technology, with consideration for reliability and experience of the manufacturer which can meet the low weight-bearing capacity criteria. The original goal of the project was to provide an opportunity to monitor the results of the BIPV technology and compare these results to other City and County of San Francisco installed PV systems. The MUNI Ways and Structures Center was acquired from the Cookson Doors Company, which had run the Center for many decades. The building was renovated in 1998, but the existing roof had not been designed to carry a large load. Due to this fact, a complete roofing and structural analysis had to be performed to match the available roof loading to the existing and/or new solar PV technology, and BIPV was considered an excellent solution for this structure with the roof weight limitations. The solar BIPV system on the large roof area was estimated to provide about 25% of the total facility load with an average of 52,560 kWh per month. In order to accomplish the goals of the project, the following steps were performed: 1. SFPUC and consultants evaluated the structural capability of the facility roof, with recommendations for improvements necessary to accommodate the solar PV system and determine the suitable size of the system in kilowatts. The electrical room and switchgear were evaluated for any improvements necessary and to identify any constraints that might impede the installation of necessary inverters, transformers or meters. 2. Development of a design-build Request for Proposal (RFP) to identify the specifications for the solar PV system, and to include SFPUC technical specifications, equipment warranties and performance warranties. Due to potential labor issues in the local solar industry, SFPUC adjusted the terms of the RFP to more clearly define scope of work between electricians, roofers and laborers. 3. Design phase of project included electrical design drawings, calculations and other construction documents to support three submittals: 50% (preliminary design), 90% (detailed design) and 100% (Department of Building Inspection permit approved). 4. Installation of solar photovoltaic panels, completion of conduit and wiring work, connection of inverters, isolation switches, meters and Data Acquisition System by Contractor (Department of Public Works). 5. Commissioning of system, including all necessary tests to make the PV system fully functional and operational at its rated capacity of 100 kW (DC-STC). Following completion of these steps, the solar PV system was installed and fully integrated by late October 2013. The interconnection with PG&E utility grid was completed and the system began generating power on November 21, 2013. The projected annual energy generation for the system is estimated at 127,120 kWh/year.

  1. Solar receiver with integrated optics

    NASA Astrophysics Data System (ADS)

    Jiang, Lun; Winston, Roland

    2012-10-01

    The current challenge for PV/Thermal (PV/T) systems is the reduction of radiation heat loss. Compared to solar thermal selective coating, the solar cells cannot be used as an efficient thermal absorber due to their large emissivity of the encapsulation material. Many commercial PV/T products therefore require a high concentration (more than 10x) to reach an acceptable thermal efficiency for their receivers. Such a concentration system inevitably has to track or semi-track, which induces additional cost and collects only the direct radiation from the sun. We propose a new PV/T design using a vacuum encapsulated thin film cell to solve this problem. The proposed design also collects the diffuse sun light efficiently by using an external compound parabolic concentrator (XCPC). Since the transparent electrode (TCO) of thin film cell is inherently transparent in visible light and reflective beyond infrared, this design uses this layer instead of the conventional solar cell encapsulation as the outmost heat loss surface. By integrating such a vacuum design with a tube shaped absorber, we reduce the complexity of conducting the heat energy and electricity out of the device. A low concentration standalone non-tracking solar collector is proposed in this paper. We also analyzed the thermosyphon system configuration using heat transfer and ray tracing models. The economics of such a receiver are presented.

  2. Analysis of urban land use in the megacity of Dhaka, Bangladesh: Roof-top detection in the context of assessing solar photovoltaic potential

    NASA Astrophysics Data System (ADS)

    Jaegermeyr, J.; Kabir, H.; Endlicher, W.

    2009-12-01

    The megacity of Dhaka, Bangladesh is considered to be one of the world’s fastest growing urban centers. With nearly 14 million people Dhaka currently faces tremendous power crisis. The available power supply of Dhaka Megacity is currently 1000-1200 MW against the maximum demand of nearly 2000 MW. The objective of this study is to classify land cover of Dhaka to locate roof-top areas which are adequate for solar photovoltaic applications. Usually this task is performed with additional building-heights data. With lack of that, we present an object-based classification approach which is based on high resolution Quickbird data only. Extensive formal buildings in Dhaka mostly have flat roof-tops made from concrete which are well suited for PV applications. The classification is focused to detect these ‘Bright Roof-Tops’ to assess a lower limit for potential PV areas. With that conservative approach bright roof-top areas of 10.554 km2 out of the city’s 134.282 km2 could be found. The overall classification accuracy is 0.918, the producer’s accuracy of ‘Bright Roof-Tops’ is 0.833. Preliminary result of the PhD work of Humayun Kabir indicates that the application of only 75 Wp stand-alone solar modules on these available bright roof-tops can generate nearly 1,000 MW of electricity. The application of solar modules with high capacity (i.e., >200 Wp) preferably through grid-connected PV systems can substantially meet-up the city’s power demand, although several techno-economic and socio-political factors are certainly involved.

  3. Automatic Analysis and Classification of the Roof Surfaces for the Installation of Solar Panels Using a Multi-Data Source and Multi-Sensor Aerial Platform

    NASA Astrophysics Data System (ADS)

    López, L.; Lagüela, S.; Picon, I.; González-Aguilera, D.

    2015-02-01

    A low-cost multi-sensor aerial platform, aerial trike, equipped with visible and thermographic sensors is used for the acquisition of all the data needed for the automatic analysis and classification of roof surfaces regarding their suitability to harbour solar panels. The geometry of a georeferenced 3D point cloud generated from visible images using photogrammetric and computer vision algorithms, and the temperatures measured on thermographic images are decisive to evaluate the surfaces, slopes, orientations and the existence of obstacles. This way, large areas may be efficiently analysed obtaining as final result the optimal locations for the placement of solar panels as well as the required geometry of the supports for the installation of the panels in those roofs where geometry is not optimal.

  4. Solar electric and thermal conversion system in close proximity to the consumer. [solar panels on house roofs

    NASA Technical Reports Server (NTRS)

    Boeer, K. W.

    1975-01-01

    Solar cells may be used to convert sunlight directly into electrical energy and into lowgrade heat to be used for large-scale terrestrial solar-energy conversion. Both forms of energy can be utilized if such cells are deployed in close proximity to the consumer (rooftop). Cadmium-sulfide/copper-sulfide (CdS/Cu2S) solar cells are an example of cells which may be produced inexpensively enough to become economically attractive. Cell parameters relevant for combined solar conversion are presented. Critical issues, such as production yield, life expectancy, and stability of performance, are discussed. Systems-design parameters related to operating temperatures are analyzed. First results obtained on Solar One, the experimental house of the University of Delaware, are given. Economic aspects are discussed. Different modes of operation are discussed in respect to the power utility and consumer incentives.

  5. A building integrated, high temperature solar thermal system for industrial applications

    SciTech Connect

    Gerics, L.J.; Nicklas, M.H.

    1996-11-01

    The paper describes a novel approach to integrating energy producing systems into the building skin and structure. Over the past several years, building integrated photovoltaic has received attention for utilizing building skins that provide a portion of a building`s electricity needs. The system described herein incorporates into a modular, substantially prefabricated construction package a roofing system that delivers weather tightness, an infiltration/exfiltration barrier, thermal insulation, radiant barrier, passive heating, natural ventilation, daylighting and, most novelly, high temperature solar energy to be used for industrial process heat, electricity generation, absorption cooling or desalination.

  6. Green Roofs

    SciTech Connect

    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.

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

    SciTech Connect

    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.

  8. Estimation of incident solar radiation on the roof of the cultural and sports university centre of the Foundation University Los Libertadores

    NASA Astrophysics Data System (ADS)

    Jiménez, S. A.; Carrillo, V. M.; Rátiva, L. C.

    2016-02-01

    This document shows the estimate of the total solar irradiance incident for the set of solar collectors to be located on the roof of cultural and sports university centre (CSUC) of the Foundation University Los Libertadores (FULL) in Bogotá, Colombia, and they will be part of the climate control system of the pool built inside. The calculation was based on experimental data of global solar radiation on the horizontal surface on March, July, October, November and December, through the three most commonly models used to determine the total solar radiation on tilted surfaces: isotropic sky, HDKR and Perez. The results show differences of less than 5% between the values calculated by the three models for December, the month with lower irradiance. For this month, reductions up to 15% and 19% were observed in the estimated irradiance, relative to those obtained on a horizontal surface on a surface under ideal orientation and inclination, respectively.

  9. Building with integral solar-heat storage--Starkville, Mississippi

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Column supporting roof also houses rock-storage bin of solar-energy system supplying more than half building space heating load. Conventional heaters supply hot water. Since bin is deeper and narrower than normal, individual pebble size was increased to keep airflow resistance at minimum.

  10. Integrating soil solarization into crop production systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil solarization remains one of but a handful of nonchemical soil disinfestation methods suitable for high-value crops such as cut-flowers, strawberry and fresh market tomato and pepper. Recognition of soil solarization within the context of an integrated pest management (IPM) approach is paramoun...

  11. Final Report. An Integrated Partnership to Create and Lead the Solar Codes and Standards Working Group

    SciTech Connect

    Rosenthal, Andrew

    2013-12-30

    The DOE grant, “An Integrated Partnership to Create and Lead the Solar Codes and Standards Working Group,” to New Mexico State University created the Solar America Board for Codes and Standards (Solar ABCs). From 2007 – 2013 with funding from this grant, Solar ABCs identified current issues, established a dialogue among key stakeholders, and catalyzed appropriate activities to support the development of codes and standards that facilitated the installation of high quality, safe photovoltaic systems. Solar ABCs brought the following resources to the PV stakeholder community; Formal coordination in the planning or revision of interrelated codes and standards removing “stove pipes” that have only roofing experts working on roofing codes, PV experts on PV codes, fire enforcement experts working on fire codes, etc.; A conduit through which all interested stakeholders were able to see the steps being taken in the development or modification of codes and standards and participate directly in the processes; A central clearing house for new documents, standards, proposed standards, analytical studies, and recommendations of best practices available to the PV community; A forum of experts that invites and welcomes all interested parties into the process of performing studies, evaluating results, and building consensus on standards and code-related topics that affect all aspects of the market; and A biennial gap analysis to formally survey the PV community to identify needs that are unmet and inhibiting the market and necessary technical developments.

  12. Roof-harvested rainwater for potable purposes: application of solar disinfection (SODIS) and limitations.

    PubMed

    Amin, Muhammad Tahir; Han, Mooyoung

    2009-01-01

    Efficiency of solar disinfection (SODIS) was evaluated for the potability of rainwater in view of the increasing water and energy crises especially in developing countries. Rainwater samples were collected from an underground storage tank in 2 L polyethylene terephthalate (PET) bottles and SODIS efficiency was evaluated at different weather conditions. For optimizing SODIS, PET bottles with different backing surfaces to enhance the optical and thermal effects of SODIS were used and different physicochemical parameters were selected and evaluated along with microbial re-growth observations and calculating microbial decay constants. Total and fecal coliforms were used along with Escherichia Coli and Heterotrophic Plate Counts (HPC) as basic microbial and indicator organisms of water quality. For irradiance less than 600 W/m(2), reflective type PET bottles were best types while for radiations greater than 700 W/m(2), absorptive type PET bottles offered best solution due to the synergistic effects of both thermal and UV radiations. Microbial inactivation did not improve significantly by changing the initial pH and turbidity values but optimum SODIS efficiency is achieved for rainwater with acidic pH and low initial turbidity values by keeping air-spaced PET bottles in undisturbed conditions. Microbial re-growth occurred after one day only at higher turbidity values and with basic pH values. First-order reaction rate constant was in accordance with recent findings for TC but contradicted with previous researches for E. coli. No microbial parameter met drinking water guidelines even under strong experimental weather conditions rendering SODIS ineffective for complete disinfection and hence needed more exposure time or stronger sunlight radiations. With maximum possible storage of rainwater, however, and by using some means for accelerating SODIS process, rainwater can be disinfected and used for potable purposes. PMID:19633384

  13. Green roofs: potential at LANL

    SciTech Connect

    Pacheco, Elena M

    2009-01-01

    Green roofs, roof systems that support vegetation, are rapidly becoming one of the most popular sustainable methods to combat urban environmental problems in North America. An extensive list of literature has been published in the past three decades recording the ecological benefits of green roofs; and now those benefits have been measured in enumerated data as a means to analyze the costs and returns of green roof technology. Most recently several studies have made substantial progress quantifying the monetary savings associated with storm water mitigation, the lessoning of the Urban Heat Island, and reduction of building cooling demands due to the implementation of green roof systems. Like any natural vegetation, a green roof is capable of absorbing the precipitation that falls on it. This capability has shown to significantly decrease the amount of storm water runoff produced by buildings as well as slow the rate at which runoff is dispensed. As a result of this reduction in volume and velocity, storm drains and sewage systems are relieved of any excess stress they might experience in a storm. For many municipalities and private building owners, any increase in storm water mitigation can result in major tax incentives and revenue that does not have to be spent on extra water treatments. Along with absorption of water, vegetation on green roofs is also capable of transpiration, the process by which moisture is evaporated into the air to cool ambient temperatures. This natural process aims to minimize the Urban Heat Island Effect, a phenomenon brought on by the dark and paved surfaces that increases air temperatures in urban cores. As the sun distributes solar radiation over a city's area, dark surfaces such as bitumen rooftops absorb solar rays and their heat. That heat is later released during the evening hours and the ambient temperatures do not cool as they normally would, creating an island of constant heat. Such excessively high temperatures induce heat strokes, heat exhaustion, and pollution that can agitate the respiratory system. The most significant savings associated with green roofs is in the reduction of cooling demands due to the green roof's thermal mass and their insulating properties. Unlike a conventional roof system, a green roof does not absorb solar radiation and transfer that heat into the interior of a building. Instead the vegetation acts as a shade barrier and stabilizes the roof temperature so that interior temperatures remain comfortable for the occupants. Consequently there is less of a demand for air conditioning, and thus less money spent on energy. At LANL the potential of green roof systems has already been realized with the construction of the accessible green roof on the Otowi building. To further explore the possibilities and prospective benefits of green roofs though, the initial capital costs must be invested. Three buildings, TA-03-1698, TA-03-0502, and TA-53-0031 have all been identified as sound candidates for a green roof retrofit project. It is recommended that LANL proceed with further analysis of these projects and implementation of the green roofs. Furthermore, it is recommended that an urban forestry program be initiated to provide supplemental support to the environmental goals of green roofs. The obstacles barring green roof construction are most often budgetary and structural concerns. Given proper resources, however, the engineers and design professionals at LANL would surely succeed in the proper implementation of green roof systems so as to optimize their ecological and monetary benefits for the entire organization.

  14. Roof Plans: Section "CC", Roof Plan; Roof Framing Plans: Section ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Roof Plans: Section "C-C", Roof Plan; Roof Framing Plans: Section "C-C", Section "D-D"; Roof Framing Sections: Cross Section "G-G", Cross Section "H-H" - Fort Washington, Fort Washington Light, Northeast side of Potomac River at Fort Washington Park, Fort Washington, Prince George's County, MD

  15. Solar central receiver integration with Hoover Dam

    SciTech Connect

    Remmers, H.E.; Zelenka, R.L.; Kitchen, J.H.

    1980-01-01

    The technical and economic feasibility of integrating a 100 MWe solar central receiver powerplant located in Yuma, Arizona with the Hoover Dam hydroelectric power system is discussed. Technical feasibility was determined by evaluating the effects of integration on the hydrologic and power operations of the existing hydro system. Economic feasibility was determined by comparing the costs of the integrated system with that of the most likely alternative source of power generation--an oil-fired,combined-cycle plant.

  16. Solar tunnel dryer with integrated collector

    SciTech Connect

    Lutz, K.; Muhlbauer, W.

    1986-01-01

    A solar tunnel dryer with integrated collector was developed and tested. This low-cost system can be produced either by small scale industries of farmers themselves using simple tools and relatively cheap materials. Depending on weather conditions about 1000 kg grapes can be dried within 4 to 7 days. According to the drying capacity the solar drying system can be successfully applied to farms with an acreage of 0.5 to 1.0 hectare.

  17. Dynamic kirigami structures for integrated solar tracking.

    PubMed

    Lamoureux, Aaron; Lee, Kyusang; Shlian, Matthew; Forrest, Stephen R; Shtein, Max

    2015-01-01

    Optical tracking is often combined with conventional flat panel solar cells to maximize electrical power generation over the course of a day. However, conventional trackers are complex and often require costly and cumbersome structural components to support system weight. Here we use kirigami (the art of paper cutting) to realize novel solar cells where tracking is integral to the structure at the substrate level. Specifically, an elegant cut pattern is made in thin-film gallium arsenide solar cells, which are then stretched to produce an array of tilted surface elements which can be controlled to within ±1°. We analyze the combined optical and mechanical properties of the tracking system, and demonstrate a mechanically robust system with optical tracking efficiencies matching conventional trackers. This design suggests a pathway towards enabling new applications for solar tracking, as well as inspiring a broader range of optoelectronic and mechanical devices. PMID:26348820

  18. Dynamic kirigami structures for integrated solar tracking

    NASA Astrophysics Data System (ADS)

    Lamoureux, Aaron; Lee, Kyusang; Shlian, Matthew; Forrest, Stephen R.; Shtein, Max

    2015-09-01

    Optical tracking is often combined with conventional flat panel solar cells to maximize electrical power generation over the course of a day. However, conventional trackers are complex and often require costly and cumbersome structural components to support system weight. Here we use kirigami (the art of paper cutting) to realize novel solar cells where tracking is integral to the structure at the substrate level. Specifically, an elegant cut pattern is made in thin-film gallium arsenide solar cells, which are then stretched to produce an array of tilted surface elements which can be controlled to within +/-1°. We analyze the combined optical and mechanical properties of the tracking system, and demonstrate a mechanically robust system with optical tracking efficiencies matching conventional trackers. This design suggests a pathway towards enabling new applications for solar tracking, as well as inspiring a broader range of optoelectronic and mechanical devices.

  19. Dynamic kirigami structures for integrated solar tracking

    PubMed Central

    Lamoureux, Aaron; Lee, Kyusang; Shlian, Matthew; Forrest, Stephen R.; Shtein, Max

    2015-01-01

    Optical tracking is often combined with conventional flat panel solar cells to maximize electrical power generation over the course of a day. However, conventional trackers are complex and often require costly and cumbersome structural components to support system weight. Here we use kirigami (the art of paper cutting) to realize novel solar cells where tracking is integral to the structure at the substrate level. Specifically, an elegant cut pattern is made in thin-film gallium arsenide solar cells, which are then stretched to produce an array of tilted surface elements which can be controlled to within ±1°. We analyze the combined optical and mechanical properties of the tracking system, and demonstrate a mechanically robust system with optical tracking efficiencies matching conventional trackers. This design suggests a pathway towards enabling new applications for solar tracking, as well as inspiring a broader range of optoelectronic and mechanical devices. PMID:26348820

  20. Understanding Roofing Systems.

    ERIC Educational Resources Information Center

    Michelsen, Ted

    2001-01-01

    Reviews the various types of multi- and single-ply roofing commonly used today in educational facilities. Roofing types described involve built-up systems, modified bitumen systems; ethylene propylene diene terpolymer roofs; and roofs of thermoplastic, metal, and foam. A description of the Roofing Industry Educational Institute is included. (GR)

  1. Integrated Solar Concentrator and Shielded Radiator

    NASA Technical Reports Server (NTRS)

    Clark, David Larry

    2010-01-01

    A shielded radiator is integrated within a solar concentrator for applications that require protection from high ambient temperatures with little convective heat transfer. This innovation uses a reflective surface to deflect ambient thermal radiation, shielding the radiator. The interior of the shield is also reflective to provide a view factor to deep space. A key feature of the shield is the parabolic shape that focuses incoming solar radiation to a line above the radiator along the length of the trough. This keeps the solar energy from adding to the radiator load. By placing solar cells along this focal line, the concentration of solar energy reduces the number and mass of required cells. By shielding the radiator, the effective reject temperature is much lower, allowing lower radiator temperatures. This is particularly important for lower-temperature processes, like habitat heat rejection and fuel cell operations where a high radiator temperature is not feasible. Adding the solar cells in the focal line uses the concentrating effect of the shield to advantage to accomplish two processes with a single device. This shield can be a deployable, lightweight Mylar structure for compact transport.

  2. Integral glass encapsulation for solar arrays

    NASA Technical Reports Server (NTRS)

    Landis, G. A.

    1981-01-01

    Electrostatic bonding technology, an encapsulation technique for terrestrial solar array was developed. The process produces full integral, hermetic bonds with no adhesives or pottants. Panels of six solar cells on a simple glass superstrate were produced. Electrostatic bonding for making the cell front contact was also developed. A metal mesh is trapped into contact with the cell front during the bonding process. Six cell panels using the bonded mesh as the only cell front contact were produced. The possibility of using lower cost glass, with a higher thermal expansion mismatch to silicon, by making lower temperature bonds is developed. However, this requires a planar surface cell.

  3. Rules To Roof By.

    ERIC Educational Resources Information Center

    Hale, Olivia

    2002-01-01

    Advises schools on keeping roofs healthy, thereby saving costly repairs to both the roof and the entire building. Discusses inspections, preventive-maintenance programs, weather, and when to re-roof. (EV)

  4. Overview of Roof Pond Systems

    NASA Astrophysics Data System (ADS)

    Marlatt, W. P.; Murray, K. A.; Squier, S. E.

    1983-11-01

    An overview of a technical report on roof pond systems is presented. The document discusses how the information for the report was gathered, the contents of the report, and the current status of completion. A summary of the impact of the report on the solar community and a general conclusions are included as well as information on the availability of the report.

  5. Transparent antennas for solar cell integration

    NASA Astrophysics Data System (ADS)

    Yasin, Tursunjan

    Transparent patch antennas are microstrip patch antennas that have a certain level of optical transparency. Highly transparent patch antennas are potentially suitable for integration with solar panels of small satellites, which are becoming increasingly important in space exploration. Traditional patch antennas employed on small satellites compete with solar cells for surface area. However, a transparent patch antenna can be placed directly on top of solar cells and resolve the issue of competing for limited surface real estate. For such an integration, a high optical transparency of the patch antenna is required from the solar cells' point of view. On the other hand, the antenna should possess at least acceptable radiation properties at the same time. This dissertation focuses on some of the most important concerns from the perspective of small satellite applications. For example, an optimization method to simultaneously improve both optical transparency and radiation efficiency of the antenna is studied. Active integrated antenna design method is extended to meshed patch applications in an attempt to improve the overall power efficiency of the front end communication subsystem. As is well known, circular polarization is immune from Faraday rotation effect in the ionosphere and thus can avoid a 3-dB loss in geo-satellite communication. Therefore, this research also aims to present design methods for circularly polarized meshed patch antennas. Moreover, a meshed patch antenna capable of supporting a high communication data rate is investigated. Lastly, other types of transparent patch antennas are also analyzed and compared to meshed patches. In summary, many properties of transparent patch antennas are examined in order to meet different design requirements.

  6. Integrated solar reforming for thermochemical energy transport

    NASA Astrophysics Data System (ADS)

    Rozenman, T.

    1987-12-01

    This report presents a design study of two reforming processes as applied to the concept of solar thermochemical energy transport. Conceptual designs were carried out for steam-methane and CO2-methane reforming plants. A solar central receiver reformer was designed as an integrated reactor with the chemical reaction tubes placed inside the receiver cavity. The two plant designs were compared for their energy efficiency and capital cost. The CO2 reforming plant design results in higher energy efficiency but requires a catalyst which is still in an experimental stage of development. A third design was performed as a modification of the steam reforming plant utilizing a Direct Contact system, in which the process steam is generated by utilizing the heat of condensation. This system resulted in the highest energy efficiency. A comparison of the capital cost of these three plant designs shows them to be equivalent within the estimation accuracy of 25 percent.

  7. Integral Glass Encapsulation for Solar Arrays

    NASA Technical Reports Server (NTRS)

    Younger, P. R.; Tobin, R. G.; Kreisman, W. S.

    1979-01-01

    Work reported was performed during the period from August 1977 to December 1978. The program objective was to continue the development of electrostatic bonding (ESB) as an encapsulation technique for terrestrial cells. Economic analyses shows that this process can be a cost-effective method of producing reliable, long lifetime solar modules. When considered in sufficient volume, both material and equipment costs are competitive with conventional encapsulation systems. In addition, the possibility of integrating cell fabrication into the encapsulation process, as in the case of the preformed cell contacts discussed in this report, offers the potential of significant overall systems cost reduction.

  8. Low concentration solar louvres for building integration

    NASA Astrophysics Data System (ADS)

    Vincenzi, D.; Aldegheri, F.; Baricordi, S.; Bernardoni, P.; Calabrese, G.; Guidi, V.; Pozzetti, L.

    2013-09-01

    The building integration of CPV modules offers several advantages over the integration of flat panel systems, but the decreasing price trend of standard modules observed in the last years has hampered the market expansion of CPV systems, which still don't rely on a low-cost mass production supply chain. To overcome this contingent issue and to foster the diffusion of innovative PV systems we developed a low concentration BIPV module with added functionalities, such as sunlight shading and building illumination. The electrical performances, retrieved under outdoor conditions, and the lighting performances of the Solar F-Light are shown. The latter indicate that it is suitable for ambient lighting, with a very limited power draw.

  9. Integrated Solar Upper Stage (ISUS) mission trades

    SciTech Connect

    Frye, P.

    1996-12-31

    Solar thermal propulsion and propulsion/power systems were recently identified as key technologies in the Operational Effectiveness and Cost Comparison Study (OECS) sponsored by Phillips Laboratory (PL). These technologies were found to be pervasively cost effective with short transfer times and very good performance across a wide range of missions. The on-going Integrated Solar Upper Stage (ISUS) Program sponsored by PL represents development of a solar thermal propulsion/power (bimodal) system. As part of this effort, mission trades are being conducted to further define the ISUS system for geosynchronous equatorial orbit (GEO), high Earth orbit (HEO-Molniya class), and mid Earth orbit (MEO-GPS class) missions. These trades will consider launch vehicles ranging in size from a LLV3 to an Atlas IIAS that insert the ISUS into low Earth orbit (LEO). These trades will be used to define the ISUS system for the planned Engine Ground Demonstration, a space demonstration mission, and as a future operational system.

  10. Integrated Access to Solar Observations With EGSO

    NASA Astrophysics Data System (ADS)

    Csillaghy, A.

    2003-12-01

    {\\b Co-Authors}: J.Aboudarham (2), E.Antonucci (3), R.D.Bentely (4), L.Ciminiera (5), A.Finkelstein (4), J.B.Gurman(6), F.Hill (7), D.Pike (8), I.Scholl (9), V.Zharkova and the EGSO development team {\\b Institutions}: (2) Observatoire de Paris-Meudon (France); (3) INAF - Istituto Nazionale di Astrofisica (Italy); (4) University College London (U.K.); (5) Politecnico di Torino (Italy), (6) NASA Goddard Space Flight Center (USA); (7) National Solar Observatory (USA); (8) Rutherford Appleton Lab. (U.K.); (9) Institut d'Astrophysique Spatial, Universite de Paris-Sud (France) ; (10) University of Bradford (U.K) {\\b Abstract}: The European Grid of Solar Observations is the European contribution to the deployment of a virtual solar observatory. The project is funded under the Information Society Technologies (IST) thematic programme of the European Commission's Fifth Framework. EGSO started in March 2002 and will last until March 2005. The project is categorized as a computer science effort. Evidently, a fair amount of issues it addresses are general to grid projects. Nevertheless, EGSO is also of benefit to the application domains, including solar physics, space weather, climate physics and astrophysics. With EGSO, researchers as well as the general public can access and combine solar data from distributed archives in an integrated virtual solar resource. Users express queries based on various search parameters. The search possibilities of EGSO extend the search possibilities of traditional data access systems. For instance, users can formulate a query to search for simultaneous observations of a specific solar event in a given number of wavelengths. In other words, users can search for observations on the basis of events and phenomena, rather than just time and location. The software architecture consists of three collaborating components: a consumer, a broker and a provider. The first component, the consumer, organizes the end user interaction and controls requests submitted to the grid. The consumer is thus in charge of tasks such as request handling, request composition, data visualization and data caching. The second component, the provider, is dedicated to data providing and processing. It links the grid to individual data providers and data centers. The third component, the broker, collects information about providers and allows consumers to perform the searches on the grid. Each component can exist in multiple instances. This follows a basic grid concept: The failure or unavailability of a single component will not generate a failure of the whole system, as other systems will take over the processing of requests. The architecture relies on a global data model for the semantics. The data model is in some way the brains of the grid. It provides a description of the information entities available within the grid, as well as a description of their relationships. EGSO is now in the development phase. A demonstration (www.egso.org/demo) is provided to get an idea about how the system will function once the project is completed. The demonstration focuses on retrieving data needed to determine the energy released in the solar atmosphere during the impulsive phase of flares. It allows finding simultaneous observations in the visible, UV, Soft X-rays, hard X-rays, gamma-rays, and radio. The types of observations that can be specified are images at high space and time resolutions as well as integrated emission and spectra from a yet limited set of instruments, including the NASA spacecraft TRACE, SOHO, RHESSI, and the ground-based observatories Phoenix-2 in Switzerland and Meudon Observatory in France

  11. Integrated Solar Upper Stage Technical Support

    NASA Technical Reports Server (NTRS)

    Jaworske, Donald A.

    1998-01-01

    NASA Lewis Research Center is participating in the Integrated Solar Upper Stage (ISUS) program. This program is a ground-based demonstration of an upper stage concept that will be used to generate both solar propulsion and solar power. Solar energy collected by a primary concentrator is directed into the aperture of a secondary concentrator and further concentrated into the aperture of a heat receiver. The energy stored in the receiver-absorber-converter is used to heat hydrogen gas to provide propulsion during the orbital transfer portion of the mission. During the balance of the mission, electric power is generated by thermionic diodes. Several materials issues were addressed as part of the technical support portion of the ISUS program, including: 1) Evaluation of primary concentrator coupons; 2) Evaluation of secondary concentrator coupons; 3) Evaluation of receiver-absorber-converter coupons; 4) Evaluation of in-test witness coupons. Two different types of primary concentrator coupons were evaluated from two different contractors-replicated coupons made from graphite-epoxy composite and coupons made from microsheet glass. Specular reflectivity measurements identified the replicated graphite-epoxy composite coupons as the primary concentrator material of choice. Several different secondary concentrator materials were evaluated, including a variety of silver and rhodium reflectors. The specular reflectivity of these materials was evaluated under vacuum at temperatures up to 800 C. The optical properties of several coupons of rhenium on graphite were evaluated to predict the thermal performance of the receiver-absorber-converter. Finally, during the ground test demonstration, witness coupons placed in strategic locations throughout the thermal vacuum facility were evaluated for contaminants. All testing for the ISUS program was completed successfully in 1997. Investigations related to materials issues have proven helpful in understanding the operation of the test article, leading to a potential ISUS flight test in 2002.

  12. Impact of Sustainable Cool Roof Technology on Building Energy Consumption

    NASA Astrophysics Data System (ADS)

    Vuppuluri, Prem Kiran

    Highly reflective roofing systems have been analyzed over several decades to evaluate their ability to meet sustainability goals, including reducing building energy consumption and mitigating the urban heat island. Studies have isolated and evaluated the effects of climate, surface reflectivity, and roof insulation on energy savings, thermal load mitigation and also ameliorating the urban heat island. Other sustainable roofing systems, like green-roofs and solar panels have been similarly evaluated. The motivation for the present study is twofold: the first goal is to present a method for simultaneous evaluation and inter-comparison of multiple roofing systems, and the second goal is to quantitatively evaluate the realized heating and cooling energy savings associated with a white roof system compared to the reduction in roof-top heat flux. To address the first research goal a field experiment was conducted at the International Harvester Building located in Portland, OR. Thermal data was collected for a white roof, vegetated roof, and a solar panel shaded vegetated roof, and the heat flux through these roofing systems was compared against a control patch of conventional dark roof membrane. The second research goal was accomplished using a building energy simulation program to determine the impact of roof area and roof insulation on the savings from a white roof, in both Portland and Phoenix. The ratio of cooling energy savings to roof heat flux reduction from replacing a dark roof with a white roof was 1:4 for the month of July, and 1:5 annually in Portland. The COP of the associated chillers ranges from 2.8-4.2, indicating that the ratio of cooling energy savings to heat flux reduction is not accounted for solely by the COP of the chillers. The results of the building simulation indicate that based on energy savings alone, white roofs are not an optimal choice for Portland. The benefits associated with cooling energy savings relative to a black roof are offset by the winter-time penalty, and the net benefit from adopting white roof technology in Portland is small. That said, there are other potential benefits of white roofing such as impact on urban heat islands and roof life that must also be considered.

  13. Western Wind and Solar Integration Study (Fact Sheet)

    SciTech Connect

    Not Available

    2012-09-01

    Initiated in 2007 to examine the operational impact of up to 35% penetration of wind, photovoltaic (PV), and concentrating solar power (CSP) energy on the electric power system, the Western Wind and Solar Integration Study (WWSIS) is one of the largest regional wind and solar integration studies to date. The goal is to understand the effects of variability and uncertainty of wind, PV, and CSP on the grid. In the Western Wind and Solar Integration Study Phase 1, solar penetration was limited to 5%. Utility-scale PV was not included because of limited capability to model sub-hourly, utility-scale PV output . New techniques allow the Western Wind and Solar Integration Study Phase 2 to include high penetrations of solar - not only CSP and rooftop PV but also utility-scale PV plants.

  14. Toward safer roof bolting

    SciTech Connect

    Not Available

    1983-10-01

    An automatic microprocessor-controlled roof bolter being developed may dramatically improve operator safety in high coal seams. The operator sits in protected cab where the controls roof bolter module out front. Hydraulic jacks anchor roof bolter module to coal mine floor and roof. Another bolter is described for metal and nonmetal mines which uses a percussive hammer for drilling. The unit operates electrohydraulically during bolting, electric power being obtained via a trailing cable. A diesel engine trams it in the mine.

  15. EPA's Green Roof Research

    EPA Science Inventory

    This is a presentation on the basics of green roof technology. The presentation highlights some of the recent ORD research projects on green roofs and provices insight for the end user as to the benefits for green roof technology. It provides links to currently available EPA re...

  16. Selecting a Roof Membrane.

    ERIC Educational Resources Information Center

    Waldron, Larry W.

    1990-01-01

    Offers a brief synopsis of the unique characteristics of the following roof membranes: (1) built-up roofing; (2) elastoplastic membranes; (3) modified bitumen membranes; (4) liquid applied membranes; and (5) metal roofing. A chart compares the characteristics of the raw membranes only. (MLF)

  17. Summer Roof Maintenance.

    ERIC Educational Resources Information Center

    Liscum, Curtis L.

    1999-01-01

    Presents the items to review in roofing maintenance to prepare for the impact of summer, including checking drainage, roof-field surface and membrane, flashings, sheet metal, and rooftop equipment, such as skylights and penthouses. A list of roofing facts facility managers should know are highlighted. (GR)

  18. Roof System EPDM Shrinkage.

    ERIC Educational Resources Information Center

    Betker, Edward

    1998-01-01

    Looks at Ethylene Propylene Diene Terpolymer rubber roof membranes and the potential problems associated with this material's shrinkage. Discusses how long such a roof should perform and issues affecting repair or replacement. Recommends that a building's function be considered in any roofing decision. (RJM)

  19. Raising the Roof.

    ERIC Educational Resources Information Center

    Savage, John

    2000-01-01

    Discusses how the use of metal standing-seam roofs can help conserve energy, and with proper maintenance, be long-lasting. An example is given of one high school's replacement of their leaking roof with a metal standing-seam roof. (GR)

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

    SciTech Connect

    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.

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

    SciTech Connect

    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 thermal stresses due to the PV laminates on sunny days. In PV laminates sunlight is converted into electricity and heat simultaneous. In case of building integrated applications, a relatively high solar absorption of amorphous silicon laminates can be utilized during the winter for solar heating purposes with PCM providing necessary heat storage capacity. However, PV laminates may also generate increased building cooling loads during the summer months. Therefore, in this project, the PCM heat sink was to minimize summer heat gains as well. The PCM-fibreglass-PV assembly and the IRR metal panels are capable of being installed directly on top of existing shingle roofs during re-roofing, precluding the need for recycling or disposal of waste materials. The PV laminates installed on the PCM attic are PVL-144 models from Uni-Solar. Each laminate contains 22 triple junction amorphous silicon solar cells connected in series. The silicon cells are of dimensions 356 mm x 239 mm (14-in. x 9.4-in.). The PVL-144 laminate is encapsulated in durable ETFE (poly-ethylene-co-tetrafluoroethylene) high light-transmissive polymer. Table 1 lists the power, voltage and current ratings of the PVL-144 panel.

  2. Roof aperture system for selective collection and control of solar energy for building heating, cooling and daylighting

    DOEpatents

    Sanders, William J.; Snyder, Marvin K.; Harter, James W.

    1983-01-01

    The amount of building heating, cooling and daylighting is controlled by at least one pair of solar energy passing panels, with each panel of the pair of panels being exposed to a separate direction of sun incidence. A shutter-shade combination is associated with each pair of panels and the shutter is connected to the shade so that rectilinear movement of the shutter causes pivotal movement of the shade.

  3. Solar energy grid integration systems "SEGIS"

    SciTech Connect

    None, None

    2007-10-01

    The inevitable transformation of the electrical grid to a more distributed generation configuration requires solar system capabilities well beyond simple net-metered, grid-connected approaches. Time-of-use and peak-demand rate structures will require more sophisticated systems designs that integrate energy management and/or energy storage into the system architecture. Controlling power flow into and from the utility grid will be required to ensure grid reliability and power quality. Alternative protection strategies will also be required to accommodate large numbers of distributed energy sources. This document provides an overview of the R&D needs and describes some pathways to promising solutions. The solutions will, in many cases, require R&D of new components, innovative inverter/controllers, energy management systems, innovative energy storage and a suite of advanced control algorithms, technical methodologies, protocols and the associated communications. It is expected that these solutions will help to push the “advanced integrated system” and “smart grid” evolutionary processes forward in a faster but focused manner.

  4. Colorful solar selective absorber integrated with different colored units.

    PubMed

    Chen, Feiliang; Wang, Shao-Wei; Liu, Xingxing; Ji, Ruonan; Li, Zhifeng; Chen, Xiaoshuang; Chen, Yuwei; Lu, Wei

    2016-01-25

    Solar selective absorbers are the core part for solar thermal technologies such as solar water heaters, concentrated solar power, solar thermoelectric generators and solar thermophotovoltaics. Colorful solar selective absorber can provide new freedom and flexibility beyond energy performance, which will lead to wider utilization of solar technologies. In this work, we present a monolithic integration of colored solar absorber array with different colors on a single substrate based on a multilayered structure of Cu/TiNxOy/TiO2/Si3N4/SiO2. A colored solar absorber array with 16 color units is demonstrated experimentally by using combinatorial deposition technique via changing the thickness of SiO2 layer. The solar absorptivity and thermal emissivity of all the color units is higher than 92% and lower than 5.5%, respectively. The colored solar selective absorber array can have colorful appearance and designable patterns while keeping high energy performance at the same time. It is a new candidate for a number of solar applications, especially for architecture integration and military camouflage. PMID:26832602

  5. Advanced Energy Efficient Roof System

    SciTech Connect

    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 options considered to date are not ideal. One approach is to insulate between the trusses at the roof plane. The construction process is time consuming and costs more than conventional attic construction. Moreover, the problems of air infiltration and thermal bridges across the insulation remain. Another approach is to use structurally insulated panels (SIPs), but conventional SIPs are unlikely to be the ultimate solution because an additional underlying support structure is required except for short spans. In addition, wood spline and metal locking joints can result in thermal bridges and gaps in the foam. This study undertook a more innovative approach to roof construction. The goal was to design and evaluate a modular energy efficient panelized roof system with the following attributes: (1) a conditioned and clear attic space for HVAC equipment and additional finished area in the attic; (2) manufactured panels that provide structure, insulation, and accommodate a variety of roofing materials; (3) panels that require support only at the ends; (4) optimal energy performance by minimizing thermal bridging and air infiltration; (5) minimal risk of moisture problems; (6) minimum 50-year life; (7) applicable to a range of house styles, climates and conditions; (8) easy erection in the field; (9) the option to incorporate factory-installed solar systems into the panel; and (10) lowest possible cost. A nationwide market study shows there is a defined market opportunity for such a panelized roof system with production and semi-custom builders in the United States. Senior personnel at top builders expressed interest in the performance attributes and indicate long-term opportunity exists if the system can deliver a clear value proposition. Specifically, builders are interested in (1) reducing construction cycle time (cost) and (2) offering increased energy efficiency to the homebuyer. Additional living space under the roof panels is another low-cost asset identified as part of the study. The market potential is enhanced through construction activity levels in target markets. Southern markets, from Florida to Texas account for 50 percent of the total new construction angled-roof volume. California contributes an additional 13 percent share of market volume. These states account for 28 to 30 million squares (2.8 to 3 billion square feet) of new construction angled roof opportunity. The major risk to implementation is the uncertainty of incorporating new design and construction elements into the construction process. By coordinating efforts to enhance the drivers for adoption and minimize the barriers, the panelized roof system stands to capitalize on a growing market demand for energy efficient building alternatives and create a compelling case for market adoption.

  6. The integration of terrestrial and extraterrestrial solar generators into existing power generation systems

    NASA Astrophysics Data System (ADS)

    Stoy, B.; Beyer, U.

    The effectiveness of a decentralized terrestrial solar-power generation system and a solar-power-satellite/microwave-transmission generation system is analyzed comparatively for the case of the Federal Republic of Germany (FRG). The models considered are a 5-GW-peak-capacity network comprising one million 50-sq-m roof arrays of Si solar cells and the 5-GW-capacity 52-sq-km-array 100-sq-km-receiver reference satellite system proposed by the DOE and NASA; both models are assumed to be integrated into the present FRG power network, and the load requirements and system outputs are compared in a series of graphs and diagrams. The terrestrial system is found to provide no savings in grid-capacity or plant-capacity requirements and minimal fuel savings (at least in the FRG climate) corresponding to at most 5 Pfennig/kWh. The satellite system, assuming that a European grid can provide an emergency reserve, offers substantial fuel and plant-capacity savings corresponding to about 8.75 Pfennig/kWh. It is pointed out that the overall economy of these systems depends on the investment costs of installing them (plus the investment cost of additional conventional plant capacity for the terrestrial model).

  7. Integrated solar upper stage alternate receiver

    SciTech Connect

    Streckert, H.H.; Begg, L.L.; Heffernan, T.F.; Horner, M.H.

    1997-12-31

    The Integrated Solar Upper Stage (ISUS) receiver is a compact orbital transfer vehicle designed to generate thrust to boost transfer payloads from low earth orbit to Molniya or geosynchronous orbits. It can provide thrust by collecting and concentrating solar flux and heating hydrogen to {approximately} 2,500 K. Simultaneously, the ISUS receiver radiates heat into an array of thermionic converters to produce electrical power. The central component consists of a graphite body with rhenium lined internal passages. The alternate receiver relies on wrought rhenium that is rolled, machined and electron-beam welded to form a complex rhenium liner system within the graphite body. All machining operations were performed by molybdenum wire electron discharge machining. The tube forming procedure was performed to minimize the amount of cold work before annealing. Electron-beam welding was performed at a current density range of {approximately} 2 to 10 A/cm{sup 2} depending on material thickness, which melts the rhenium locally and results in a fine grained weld zone. A simplified Demonstration Test Assembly was fabricated and tested. The unit consisted of an inlet structure welded to a manifold with a simplified exhaust nozzle system and contained in a machined graphite body. The external graphite surfaces were coated with plasma sprayed rhenium for protection from graphite erosion. Testing included a hot hydrogen flow test to {approximately} 2,500 K. The main ISUS Alternate Receiver was designed and built according to the same procedures as the demonstration unit. However, the inlet and outlet plenums are more complex and are connected by 195 channels to efficiently transfer heat to the flowing hydrogen. An outlet tube containing a sonic orifice mates to the exhaust plenum.

  8. Lightweight, self-ballasting photovoltaic roofing assembly

    DOEpatents

    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.

  9. Lightweight, self-ballasting photovoltaic roofing assembly

    DOEpatents

    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.

  10. Lightweight, self-ballasting photovoltaic roofing assembly

    SciTech Connect

    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.

  11. Solar domestic hot water in Seattle: the relative effects of collector tilt and orientation of annual performance or Ma'am the roof is the least of your worries

    SciTech Connect

    Hogan, J.F.

    1981-01-01

    Current rules of thumb for the mounting of flat plate collectors for solar domestic hot water systems actually tend to discourage the installation of systems by specifying a narrow range of acceptable tilts and orientations. Computer simulation indicates that annual performance equivalent to 80% of the optimum achievable is possible in Seattle with wide variations in tilt and orientation due to the year-round nature of the load. For due south orientations it is almost impossible to achieve less than 80% of optimum performance is achievable with the majority of collector tilts. These simulations indicate that virtually all existing south-facing roof slopes are acceptable as is. But further, it also shows that the other half of Seattle roofs that face east and west with an average slope of 25/sup 0/ have great potential and should not be summarily dismissed as impossible candidates.

  12. Design and spacecraft-integration of RTGs for solar probe

    NASA Technical Reports Server (NTRS)

    Schock, A.; Noravian, H.; Or, T.; Sankarankandath, V.

    1990-01-01

    The design, analysis, and spacecraft integration of radioisotope thermoelectric generators (RTG) to power the Solar Probe under study at NASA JPL is described. The mission of the Solar Probe is to explore the solar corona by performing in situ measurements at up to four solar radii to the sun. Design constraints for the RTG are discussed. The chief challenge in the design and system integration of the Solar Probe's RTG is a heat rejection problem. Two RTG orientations, horizontal and oblique, are analyzed for effectiveness and results are summarized in chart form. A number of cooling strategies are also investigated, including heat-pipe and reflector-cooled options. A methodology and general computer code are presented for analyzing the performance of arbitrarily obstructed RTGs with both axial and circumferential temperature, voltage, and current variation. This methodology is applied to the specific example of the Solar Probe RTG obstructed by a semicylindrical reflector of 15-inch radius.

  13. IMPROVED ROOF STABILIZATION TECHNOLOGIES

    SciTech Connect

    M.A. Ebadian, Ph.D.

    1999-01-01

    Many U.S. Department of Energy (DOE) remediation sites have performed roof repair and roof replacement to stabilize facilities prior to performing deactivation and decommissioning (D&D) activities. This project will review the decision criteria used by these DOE sites, along with the type of repair system used for each different roof type. Based on this information, along with that compiled from roofing experts, a decision-making tool will be generated to aid in selecting the proper roof repair systems. Where appropriate, innovative technologies will be reviewed and applied to the decision-making tool to determine their applicability. Based on the results, applied research and development will be conducted to develop a method to repair these existing roofing systems, while providing protection for the D and D worker in a cost-efficient manner.

  14. What's Up with Your Roof?

    ERIC Educational Resources Information Center

    Kalinger, Peter

    1998-01-01

    Explains the importance of knowing what condition the school's roof(s) is in and how to design a preventive maintenance program that is cost effective and will help extend the roof's lifecycle. Cost calculation techniques to value a roof maintenance program, maintenance documentation requirements, and roof surveying are discussed. (GR)

  15. Integrating Solar PV in Utility System Operations

    SciTech Connect

    Mills, A.; Botterud, A.; Wu, J.; Zhou, Z.; Hodge, B-M.; Heany, M.

    2013-10-31

    This study develops a systematic framework for estimating the increase in operating costs due to uncertainty and variability in renewable resources, uses the framework to quantify the integration costs associated with sub-hourly solar power variability and uncertainty, and shows how changes in system operations may affect these costs. Toward this end, we present a statistical method for estimating the required balancing reserves to maintain system reliability along with a model for commitment and dispatch of the portfolio of thermal and renewable resources at different stages of system operations. We estimate the costs of sub-hourly solar variability, short-term forecast errors, and day-ahead (DA) forecast errors as the difference in production costs between a case with “realistic” PV (i.e., subhourly solar variability and uncertainty are fully included in the modeling) and a case with “well behaved” PV (i.e., PV is assumed to have no sub-hourly variability and can be perfectly forecasted). In addition, we highlight current practices that allow utilities to compensate for the issues encountered at the sub-hourly time frame with increased levels of PV penetration. In this analysis we use the analytical framework to simulate utility operations with increasing deployment of PV in a case study of Arizona Public Service Company (APS), a utility in the southwestern United States. In our analysis, we focus on three processes that are important in understanding the management of PV variability and uncertainty in power system operations. First, we represent the decisions made the day before the operating day through a DA commitment model that relies on imperfect DA forecasts of load and wind as well as PV generation. Second, we represent the decisions made by schedulers in the operating day through hour-ahead (HA) scheduling. Peaking units can be committed or decommitted in the HA schedules and online units can be redispatched using forecasts that are improved relative to DA forecasts, but still imperfect. Finally, we represent decisions within the operating hour by schedulers and transmission system operators as real-time (RT) balancing. We simulate the DA and HA scheduling processes with a detailed unit-commitment (UC) and economic dispatch (ED) optimization model. This model creates a least-cost dispatch and commitment plan for the conventional generating units using forecasts and reserve requirements as inputs. We consider only the generation units and load of the utility in this analysis; we do not consider opportunities to trade power with neighboring utilities. We also do not consider provision of reserves from renewables or from demand-side options. We estimate dynamic reserve requirements in order to meet reliability requirements in the RT operations, considering the uncertainty and variability in load, solar PV, and wind resources. Balancing reserve requirements are based on the 2.5th and 97.5th percentile of 1-min deviations from the HA schedule in a previous year. We then simulate RT deployment of balancing reserves using a separate minute-by-minute simulation of deviations from the HA schedules in the operating year. In the simulations we assume that balancing reserves can be fully deployed in 10 min. The minute-by-minute deviations account for HA forecasting errors and the actual variability of the load, wind, and solar generation. Using these minute-by-minute deviations and deployment of balancing reserves, we evaluate the impact of PV on system reliability through the calculation of the standard reliability metric called Control Performance Standard 2 (CPS2). Broadly speaking, the CPS2 score measures the percentage of 10-min periods in which a balancing area is able to balance supply and demand within a specific threshold. Compliance with the North American Electric Reliability Corporation (NERC) reliability standards requires that the CPS2 score must exceed 90% (i.e., the balancing area must maintain adequate balance for 90% of the 10-min periods). The combination of representing DA forecast errors in the DA commitments, using 1-min PV data to simulate RT balancing, and estimates of reliability performance through the CPS2 metric, all factors that are important to operating systems with increasing amounts of PV, makes this study unique in its scope.

  16. Small integrated solar energy systems for developing countries

    NASA Astrophysics Data System (ADS)

    Schreitmueller, K. R.

    1982-11-01

    Solar enegy applications in developing countries cover processing of food and other agricultural products, fresh water production, operation of cooling and freezing equipment, of water pumps and processing machinery. Evacuated tubular collectors turn out to be best suited for process heat generation; photovoltaic generators for electricity production. The Mexican fisher village of Las Barrancas gives a good example of an integrated solar energy system.

  17. Eastern Renewable Generation Integration Study Solar Dataset (Presentation)

    SciTech Connect

    Hummon, M.

    2014-04-01

    The National Renewable Energy Laboratory produced solar power production data for the Eastern Renewable Generation Integration Study (ERGIS) including "real time" 5-minute interval data, "four hour ahead forecast" 60-minute interval data, and "day-ahead forecast" 60-minute interval data for the year 2006. This presentation provides a brief overview of the three solar power datasets.

  18. Western Wind and Solar Integration Study Phase 3: Technical Overview

    SciTech Connect

    2015-11-01

    Technical fact sheet outlining the key findings of Phase 3 of the Western Wind and Solar Integration Study (WWSIS-3). NREL and GE find that with good system planning, sound engineering practices, and commercially available technologies, the Western grid can maintain reliability and stability during the crucial first minute after grid disturbances with high penetrations of wind and solar power.

  19. Western Wind and Solar Integration Study Phase 2 (Fact Sheet)

    SciTech Connect

    Not Available

    2013-09-01

    This is one-page, two-sided fact sheet presents high-level summary results of the Western Wind and Solar Integration Study Phase 2, which examined operational impacts of high penetrations of variable renewable generation in the West.

  20. Western Wind and Solar Integration Study: Phase 2 (Presentation)

    SciTech Connect

    Lew, D.; Brinkman, G.; Ibanez, E.; Lefton, S.; Kumar, N.; Venkataraman, S.; Jordan, G.

    2013-09-01

    This presentation summarizes the scope and results of the Western Wind and Solar Integration Study Phase 2, which examined operational impacts of high penetrations of variable renewable generation in the West.

  1. Daniel K. Inouye Solar Telescope: integration testing and commissioning planning

    NASA Astrophysics Data System (ADS)

    Craig, Simon; Bulau, Scott E.; Gonzales, Kerry; Hansen, Eric; Goodrich, Bret; Hubbard, Robert P.; Johansson, Eric; Liang, Chen; Kneale, Ruth A.; McBride, William; Sekulic, Predrag; Williams, Timothy R.

    2014-08-01

    The Daniel K. Inouye Solar Telescope (DKIST), formerly the Advanced Technology Solar Telescope (ATST), has been in its construction phase since 2010, anticipating the onset of the integration, test, and commissioning (IT&C) phase late in 2016, and the commencement of science verification in early 2019. In this paper we describe the planning of the Integration, Testing and Commissioning (IT&C) phase of the project.

  2. Weathering of Roofing Materials-An Overview

    SciTech Connect

    Berdahl, Paul; Akbari, Hashem; Levinson, Ronnen; Miller, William A.

    2006-03-30

    An overview of several aspects of the weathering of roofing materials is presented. Degradation of materials initiated by ultraviolet radiation is discussed for plastics used in roofing, as well as wood and asphalt. Elevated temperatures accelerate many deleterious chemical reactions and hasten diffusion of material components. Effects of moisture include decay of wood, acceleration of corrosion of metals, staining of clay, and freeze-thaw damage. Soiling of roofing materials causes objectionable stains and reduces the solar reflectance of reflective materials. (Soiling of non-reflective materials can also increase solar reflectance.) Soiling can be attributed to biological growth (e.g., cyanobacteria, fungi, algae), deposits of organic and mineral particles, and to the accumulation of flyash, hydrocarbons and soot from combustion.

  3. Cool Roof Systems; What is the Condensation Risk?

    SciTech Connect

    Kehrer, Manfred; Pallin, Simon B

    2014-01-01

    A white roof, or cool roof, is constructed to decrease thermal loads from solar radiation, therefore saving energy by decreasing the cooling demands. Unfortunately, cool roofs with a mechanically attached membrane have shown a higher risk of intermediate condensation in the materials below the membrane in certain climates (Ennis & Kehrer, 2011) and in comparison with similar constructions with a darker exterior surface (Bludau, Zirkelbach, & Kuenzel, 2009). As a consequence, questions have been raised regarding the sustainability and reliability of using cool roof membranes in northern U.S. climate zones.

  4. Integral glass encapsulation for solar arrays

    NASA Technical Reports Server (NTRS)

    Young, P. R.

    1977-01-01

    Electrostatic bonding has been used to join silicon solar cells to borosilicate glass without the aid of any organic binders or adhesives. The results of this investigation have been to demonstrate, without question, the feasibility of this process as an encapsulation technique. The potential of ESB for terrestrial solar arrays was clearly shown. The process is fast, reproducible, and produces a permanent bond between glass and silicon that is stronger than the silicon itself. Since this process is a glass sealing technique requiring no organics it makes moisture tight sealing of solar cells possible.

  5. The Western Wind and Solar Integration Study Phase 2

    SciTech Connect

    Lew, D.; Brinkman, G.; Ibanez, E.; Hodge, B. M.; Hummon, M.; Florita, A.; Heaney, M.

    2013-09-01

    The electric grid is a highly complex, interconnected machine, and changing one part of the grid can have consequences elsewhere. Adding wind and solar affects the operation of the other power plants and adding high penetrations can induce cycling of fossil-fueled generators. Cycling leads to wear-and-tear costs and changes in emissions. Phase 2 of the Western Wind and Solar Integration Study (WWSIS-2) evaluated these costs and emissions and simulated grid operations for a year to investigate the detailed impact of wind and solar on the fossil-fueled fleet. This built on Phase 1, one of the largest wind and solar integration studies ever conducted, which examined operational impacts of high wind and solar penetrations in the West.

  6. The Western Wind and Solar Integration Study Phase 2

    SciTech Connect

    Lew, Debra; Brinkman, Greg; Ibanez, E.; Florita, A.; Heaney, M.; Hodge, B. -M.; Hummon, M.; Stark, G.; King, J.; Lefton, S. A.; Kumar, N.; Agan, D.; Jordan, G.; Venkataraman, S.

    2013-09-01

    The electric grid is a highly complex, interconnected machine, and changing one part of the grid can have consequences elsewhere. Adding wind and solar affects the operation of the other power plants and adding high penetrations can induce cycling of fossil-fueled generators. Cycling leads to wear-and-tear costs and changes in emissions. Phase 2 of the Western Wind and Solar Integration Study (WWSIS-2) evaluated these costs and emissions and simulated grid operations for a year to investigate the detailed impact of wind and solar on the fossil-fueled fleet. This built on Phase 1, one of the largest wind and solar integration studies ever conducted, which examined operational impacts of high wind and solar penetrations in the West(GE Energy 2010).

  7. LIGHTWEIGHT GREEN ROOF SYSTEMS

    EPA Science Inventory

    Applying a Lightweight Green Roof System to a building can achieve in managing storm water runoff, decreasing heat gain, yielding energy savings, and mitigating the heat island effect. Currently, Most green roof systems are considerably heavy and require structural reinforceme...

  8. Why Cool Roofs?

    ScienceCinema

    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. Roofing Source File.

    ERIC Educational Resources Information Center

    American School & University, 1998

    1998-01-01

    Provides guidelines for school administrators to aid in the selection of school-roofing systems, and information required to make specification and purchasing decisions. Low-slope roofing systems are examined, as are multiply systems such as modified bitumen, EPDM, thermoplastic, metal, and foam. (GR)

  10. Why Cool Roofs?

    SciTech Connect

    Chu, Steven

    2010-01-01

    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.

  11. Guide to Cool Roofs

    SciTech Connect

    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.

  12. ROOFING, PART 2. WORKBOOK.

    ERIC Educational Resources Information Center

    WOLTJES, WILLIAM; AND OTHERS

    THE TECHNICAL INFORMATION IN THIS STUDY GUIDE WAS PLANNED UNDER THE DIRECTION OF THE STATE EDUCATIONAL ADVISORY COMMITTEE FOR THE ROOFING TRADE AND WRITTEN BY AN APPRENTICE TRAINING SPECIALIST AND OTHERS TO BE USED AS RELATED CLASSROOM INSTRUCTION IN THE APPRENTICE TRAINING PROGRAM FOR ROOFERS. THE UNITS INCLUDE (1) BUILT-UP ROOFING, DAMPPROOFING,…

  13. Evaluation of Green Roof Plants and Materials for Semi-Arid Climates

    EPA Science Inventory

    Abstract While green roof systems have proven to be highly effective in the evaporative cooling of buildings, reduction of roof top temperatures, protection of roof membranes from solar radiation degradation, reducing stormwater runoff, as well as beautification of the urban roo...

  14. Integrated Solar Power Converters: Wafer-Level Sub-Module Integrated DC/DC Converter

    SciTech Connect

    2012-02-09

    Solar ADEPT Project: CU-Boulder is developing advanced power conversion components that can be integrated into individual solar panels to improve energy yields. The solar energy that is absorbed and collected by a solar panel is converted into useable energy for the grid through an electronic component called an inverter. Many large, conventional solar energy systems use one, central inverter to convert energy. CU-Boulder is integrating smaller, microinverters into individual solar panels to improve the efficiency of energy collection. The University’s microinverters rely on electrical components that direct energy at high speeds and ensure that minimal energy is lost during the conversion process—improving the overall efficiency of the power conversion process. CU-Boulder is designing its power conversion devices for use on any type of solar panel.

  15. COOL ROOF COATINGS INCORPORATING GLASS HOLLOW MICROSPHERES

    EPA Science Inventory

    Solar Gain is in part responsible for up to 56% of energy consumed by cooling systems in residential buildings. By reflecting and scattering radiant energy from the sun, the surface temperature of exterior walls and roofs can be greatly reduced. Previous studies have indicated...

  16. Roofing Workbook and Tests: Rigid Roofing.

    ERIC Educational Resources Information Center

    Klingensmith, Robert, Ed.

    This document is one of a series of nine individual units of instruction for use in roofing apprenticeship classes in California. The unit consists of a workbook and test. Eight topics are covered in the workbook and corresponding multiple-choice tests. For each topic, objectives and information sheets are provided. Information sheets are…

  17. Protected Membrane Roofs: A Sustainable Roofing Solution.

    ERIC Educational Resources Information Center

    Roodvoets, David L.

    2003-01-01

    Examines the benefits of protected membrane roofing (PMR) for school buildings. PMR uses an upside-down approach, where the insulation is placed on top of the waterproofing membrane to improve membrane effectiveness, reduce ultraviolet degradation, and improve insulation efficiency. The article explains what makes PMR sustainable, focusing on…

  18. Installation package - home solar heater

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Installation of commerical solar-heating system at two story, three bedroom house in New Hampshire is described in 65 page report. System collectors are integrated part of building replacing conventional roofing or siding. Report also includes general description of system, its operation and guidelines, orientation and references.

  19. Improved roof stabilization technologies

    SciTech Connect

    Ebadian, M.A.

    1998-01-01

    Decontamination and decommissioning (D and D) activities require that personnel have access to all areas of structures, some of which are more than 40 years old. In many cases, these structures have remained in a standby condition for up to 10 years; few preventative maintenance activities have been performed on them because of lack of funding or a defined future plan of action. This situation has led to deteriorated building conditions, resulting in potential personnel safety hazards. In addition, leaky roofs allow water to enter the buildings, which can cause the spread of contamination and increase building deterioration, worsening the already unsafe working conditions. To ensure worker safety and facilitate building dismantlement, the assessment of roof stabilization techniques applicable to US Department of Energy (DOE) structures has become an important issue. During Fiscal year 1997 (FY97), a comprehensive reliability-based model for the structural stabilization analysis of roof system in complex structures was developed. The model consists of three major components: a material testing method, a deterministic structural computer model, and a reliability-based optimization, and probabilistic analyses of roof structures can be implemented. Given site-specific needs, this model recommends the most appropriate roof stabilization system. This model will give not only an accurate evaluation of the existing roof system in complex structures, but it will also be a reliable method to aid the decision-making process. This final report includes in its appendix a Users` Manual for the Program of Deterministic and Reliability Analysis of Roof Structures.

  20. Solar charging

    SciTech Connect

    Heckeroth, S.; McLees, C.

    1996-11-01

    Concern about the depletion of non-renewable energy resources and the life threatening pollution and climatic changes caused by their use has led to a renewed interest in passive solar design. However, transportation consumes four times the energy used in housing and causes about 10 times the air pollution because of its total reliance on petroleum. This paper will suggest direct solar charging opportunities that can be integrated into the built environment. Major advances in electric vehicle (EV) and photovoltaic (PV) technologies will soon make solar charging a viable option for transportation. More efficient motors, high-power controllers, quick chargers and new developments in battery technology will soon make electric vehicles have performance comparable to gas vehicles. The rise in efficiency, the decreasing cost and the integration of photovoltaic panels as roofing will make workplace and home solar charging an economic alternative to the gas pump.

  1. Influence of solar heating on the performance of integrated solar cell microstrip patch antennas

    SciTech Connect

    Roo-Ons, M.J.; Shynu, S.V.; Ammann, M.J.; Seredynski, M.; McCormack, S.J.; Norton, B.

    2010-09-15

    The integration of microstrip patch antennas with photovoltaics has been proposed for applications in autonomous wireless communication systems located on building facades. Full integration was achieved using polycrystalline silicon solar cells as both antenna ground plane and direct current power generation in the same device. An overview of the proposed photovoltaic antenna designs is provided and the variation characterised of the electromagnetic properties of the device with temperature and solar radiation. Measurements for both copper and solar antennas are reported on three different commercial laminates with contrasting values for thermal coefficient of the dielectric constant. (author)

  2. Role of Concentrating Solar Power in Integrating Solar and Wind Energy: Preprint

    SciTech Connect

    Denholm, P.; Mehos, M.

    2015-06-03

    As wind and solar photovoltaics (PV) increase in penetration it is increasingly important to examine enabling technologies that can help integrate these resources at large scale. Concentrating solar power (CSP) when deployed with thermal energy storage (TES) can provide multiple services that can help integrate variable generation (VG) resources such as wind and PV. CSP with TES can provide firm, highly flexible capacity, reducing minimum generation constraints which limit penetration and results in curtailment. By acting as an enabling technology, CSP can complement PV and wind, substantially increasing their penetration in locations with adequate solar resource.

  3. Roof bolting equipment & technology

    SciTech Connect

    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.

  4. Spectrophotometer-Integrating-Sphere System for Computing Solar Absorptance

    NASA Technical Reports Server (NTRS)

    Witte, William G., Jr.; Slemp, Wayne S.; Perry, John E., Jr.

    1991-01-01

    A commercially available ultraviolet, visible, near-infrared spectrophotometer was modified to utilize an 8-inch-diameter modified Edwards-type integrated sphere. Software was written so that the reflectance spectra could be used to obtain solar absorptance values of 1-inch-diameter specimens. A descriptions of the system, spectral reflectance, and software for calculation of solar absorptance from reflectance data are presented.

  5. Green Roofs for Stormwater Management

    EPA Science Inventory

    This project evaluated green roofs as a stormwater management tool. Results indicate that the green roofs are capable of removing 40% of the annual rainfall volume from a roof through retention and evapotranspiration. Rainfall not retained by green roofs is detained, effectively...

  6. GREEN ROOFS A GROWING TREND

    EPA Science Inventory

    One of the most interesting stormwater control systems under evaluation by EPA are green roofs. Green roofs are vegetative covers applied to building roofs to slow, or totally absorb, rainfall runoff during storms. While the concept of over-planted roofs is very ancient, the go...

  7. Integrated photoelectrochemical energy storage: solar hydrogen generation and supercapacitor

    NASA Astrophysics Data System (ADS)

    Xia, Xinhui; Luo, Jingshan; Zeng, Zhiyuan; Guan, Cao; Zhang, Yongqi; Tu, Jiangping; Zhang, Hua; Fan, Hong Jin

    2012-12-01

    Current solar energy harvest and storage are so far realized by independent technologies (such as solar cell and batteries), by which only a fraction of solar energy is utilized. It is highly desirable to improve the utilization efficiency of solar energy. Here, we construct an integrated photoelectrochemical device with simultaneous supercapacitor and hydrogen evolution functions based on TiO2/transition metal hydroxides/oxides core/shell nanorod arrays. The feasibility of solar-driven pseudocapacitance is clearly demonstrated, and the charge/discharge is indicated by reversible color changes (photochromism). In such an integrated device, the photogenerated electrons are utilized for H2 generation and holes for pseudocapacitive charging, so that both the reductive and oxidative energies are captured and converted. Specific capacitances of 482 F g-1 at 0.5 A g-1 and 287 F g-1 at 1 A g-1 are obtained with TiO2/Ni(OH)2 nanorod arrays. This study provides a new research strategy for integrated pseudocapacitor and solar energy application.

  8. Integrated photoelectrochemical energy storage: solar hydrogen generation and supercapacitor

    PubMed Central

    Xia, Xinhui; Luo, Jingshan; Zeng, Zhiyuan; Guan, Cao; Zhang, Yongqi; Tu, Jiangping; Zhang, Hua; Fan, Hong Jin

    2012-01-01

    Current solar energy harvest and storage are so far realized by independent technologies (such as solar cell and batteries), by which only a fraction of solar energy is utilized. It is highly desirable to improve the utilization efficiency of solar energy. Here, we construct an integrated photoelectrochemical device with simultaneous supercapacitor and hydrogen evolution functions based on TiO2/transition metal hydroxides/oxides core/shell nanorod arrays. The feasibility of solar-driven pseudocapacitance is clearly demonstrated, and the charge/discharge is indicated by reversible color changes (photochromism). In such an integrated device, the photogenerated electrons are utilized for H2 generation and holes for pseudocapacitive charging, so that both the reductive and oxidative energies are captured and converted. Specific capacitances of 482 F g−1 at 0.5 A g−1 and 287 F g−1 at 1 A g−1 are obtained with TiO2/Ni(OH)2 nanorod arrays. This study provides a new research strategy for integrated pseudocapacitor and solar energy application. PMID:23248745

  9. Integration of LIDAR Data Into a Municipal GIS to Study Solar Radiation

    NASA Astrophysics Data System (ADS)

    Africani, P.; Bitelli, G.; Lambertini, A.; Minghetti, A.; Paselli, E.

    2013-04-01

    Identifying the right roofs to install solar panels inside a urban area is crucial for both private citizens and the whole local population. The aim is not easy because a lot of consideration must be made: insolation, orientation of the surface, size of the surface, shading due to topography, shading due to taller buildings next the surface, shading due to taller vegetation and other possible problems typical of urban areas like the presence of chimneys. Accuracy of data related to the analyzed surfaces is indeed fundamental, and also the detail of geometric models used to represent buildings and their roofs. The complexity that these roofs can reach is elevated. This work uses LiDAR data to obtain, with a semi-automatic technique, the full geometry of each roof part complementing the pre-existing building data in the municipal cartography. With this data is possible to evaluate the placement of solar panels on roofs of a whole city analyzing the solar potential of each building in detail. Other traditional techniques, like photogrammetry, need strong manual editing effort in order to identify slopes and insert vector on surfaces at the right height. Regarding LiDAR data, in order to perform accurate modelling, it is necessary to obtain an high density point cloud. The method proposed can also be used as a fast and linear workflow process for an area where LiDAR data are available and a municipal cartography already exist: LiDAR data can be furthermore successfully used to cross-check errors in pre-existent digital cartography that can remain otherwise hidden.

  10. Research and Development Needs for Building-Integrated Solar Technologies

    SciTech Connect

    none,

    2014-01-01

    The Building Technologies Office (BTO) has identified Building Integrated Solar Technologies (BIST) as a potentially valuable piece of the comprehensive pathway to help achieve its goal of reducing energy consumption in residential and commercial buildings by 50% by the year 2030. This report helps to identify the key research and development (R&D) needs that will be required for BIST to make a substantial contribution toward that goal. BIST include technologies for space heating and cooling, water heating, hybrid photovoltaic-thermal systems (PV/T), active solar lighting, and building-integrated photovoltaics (BIPV).

  11. Integrated solar thermochemical reaction system for steam methane reforming

    SciTech Connect

    Zheng, Feng; Diver, Rich; Caldwell, Dustin D.; Fritz, Brad G.; Cameron, Richard J.; Humble, Paul H.; TeGrotenhuis, Ward E.; Dagle, Robert A.; Wegeng, Robert S.

    2015-06-05

    Solar-aided upgrade of the energy content of fossil fuels, such as natural gas, can provide a near-term transition path towards a future solar-fuel economy and reduce carbon dioxide emission from fossil fuel consumption. Both steam and dry reforming a methane-containing fuel stream have been studied with concentrated solar power as the energy input to drive the highly endothermic reactions but the concept has not been demonstrated at a commercial scale. Under a current project with the U.S. Department of Energy, PNNL is developing an integrated solar thermochemical reaction system that combines solar concentrators with micro- and meso-channel reactors and heat exchangers to accomplish more than 20% solar augment of methane higher heating value. The objective of our three-year project is to develop and prepare for commercialization such solar reforming system with a high enough efficiency to serve as the frontend of a conventional natural gas (or biogas) combined cycle power plant, producing power with a levelized cost of electricity less than 6¢/kWh, without subsidies, by the year 2020. In this paper, we present results from the first year of our project that demonstrated a solar-to-chemical energy conversion efficiency as high as 69% with a prototype reaction system.

  12. Integrated solar thermochemical reaction system for steam methane reforming

    DOE PAGESBeta

    Zheng, Feng; Diver, Rich; Caldwell, Dustin D.; Fritz, Brad G.; Cameron, Richard J.; Humble, Paul H.; TeGrotenhuis, Ward E.; Dagle, Robert A.; Wegeng, Robert S.

    2015-06-05

    Solar-aided upgrade of the energy content of fossil fuels, such as natural gas, can provide a near-term transition path towards a future solar-fuel economy and reduce carbon dioxide emission from fossil fuel consumption. Both steam and dry reforming a methane-containing fuel stream have been studied with concentrated solar power as the energy input to drive the highly endothermic reactions but the concept has not been demonstrated at a commercial scale. Under a current project with the U.S. Department of Energy, PNNL is developing an integrated solar thermochemical reaction system that combines solar concentrators with micro- and meso-channel reactors and heatmore » exchangers to accomplish more than 20% solar augment of methane higher heating value. The objective of our three-year project is to develop and prepare for commercialization such solar reforming system with a high enough efficiency to serve as the frontend of a conventional natural gas (or biogas) combined cycle power plant, producing power with a levelized cost of electricity less than 6¢/kWh, without subsidies, by the year 2020. In this paper, we present results from the first year of our project that demonstrated a solar-to-chemical energy conversion efficiency as high as 69% with a prototype reaction system.« less

  13. Development of integral covers on solar cells

    NASA Technical Reports Server (NTRS)

    Stella, P.; Somberg, H.

    1971-01-01

    The electron-beam technique for evaporating a dielectric material onto solar cells is investigated. A process has been developed which will provide a highly transparent, low stress, 2 mil thick cover capable of withstanding conventional space type qualification tests including humidity, thermal shock, and thermal cycling. The covers have demonstrated the ability to withstand 10 to the 15th power 1 MeV electrons and UV irradiation with minor darkening. Investigation of the cell AR coating has produced a space qualifiable titanium oxide coating which will give an additional 6% current output over similar silicon oxide coated cells when covered by glass.

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

    SciTech Connect

    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 the 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.

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

    DOE PAGESBeta

    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

  16. Integrated Solar Array and Reflectarray Antenna for High Bandwidth Cubesats

    NASA Technical Reports Server (NTRS)

    Lewis, Dorothy; Martinez, Andres; Petro, Andrew

    2015-01-01

    The Integrated Solar Array and Reflectarray Antenna (ISARA) mission will demonstrate a reflectarray antenna that increases downlink data rates for Cube- Sats from the existing baseline rate of 9.6 kilobits per second (kbps) to more than 100 megabits per second (Mbps). The ISARA spacecraft is slated for launch no earlier than Dec. 1, 2015.

  17. A Review of Methods for the Manufacture of Residential Roofing Materials

    SciTech Connect

    Akbari, Hashem; Levinson, Ronnen; Berdahl, Paul

    2003-06-01

    Shingles, tiles, and metal products comprise over 80% (by roof area) of the California roofing market (54-58% fiberglass shingle, 8-10% concrete tile, 8-10% clay tile, 7% metal, 3% wood shake, and 3% slate). In climates with significant demand for cooling energy, increasing roof solar reflectance reduces energy consumption in mechanically cooled buildings, and improves occupant comfort in non-conditioned buildings. This report examines methods for manufacturing fiberglass shingles, concrete tiles, clay tiles, and metal roofing. The report also discusses innovative methods for increasing the solar reflectance of these roofing materials. We have focused on these four roofing products because they are typically colored with pigmented coatings or additives. A better understanding of the current practices for manufacturing colored roofing materials would allow us to develop cool colored materials creatively and more effectively.

  18. Solar cells having integral collector grids

    NASA Technical Reports Server (NTRS)

    Evans, J. C., Jr. (Inventor)

    1978-01-01

    A heterojunction or Schottky barrier photovoltaic device is described, comprising a conductive base metal layer. A back surface field region was formed at the interface between the device and the base metal layer, a transparent, conductive mixed metal oxide layer in integral contact with the n-type layer of the heterojunction or Schottky barrier device. A metal alloy grid network was included. An insulating layer prevented electrical contact between the conductive metal base layer and the transparent, conductive metal oxide layer.

  19. Integrated thermal solar heat pump system

    SciTech Connect

    Shaw, D.N.

    1980-04-08

    A compression module may comprise a hermetic helical screw rotary compressor having injection and ejection ports in addition to discharge and suction ports or may comprise a multiple cylinder, multiple level, reciprocating compressor. The module incorporates a subcooler coil and is connected to an outside air coil, a thermal energy storage coil, a direct solar energy supply coil, one or more inside coils for the space to be conditioned and a hot water coil through common, discharge manifold, suction manifold, liquid drain manifold and liquid feed manifold, by suitable solenoid operated control valves and check valves. The solenoid operated control valves are selectively operated in response to system operating parameters. Seal pots and positive displacement pumps may operate to force liquid refrigerant condensed at intermediate pressure to flow to the receiver which is pressurized at a pressure corresponding to the condensation temperature of the highest pressure condensing coil in the system. Alternatively, liquid refrigerant expansion may be used to reach a common receiver pressure for all condenser returns.

  20. Design and Spacecraft-Integration of RTGs for Solar Probe

    SciTech Connect

    Schock, Alfred

    1990-10-01

    Presented at the 41st Congress of the IAF, October 6-12, 1990 in Dresden, FRG. The paper describes the design and analysis of Radioisotope Thermoelectric Generators integrated with JPL's planned Solar Probe spacecraft. The principle purpose of the Solar probe mission is to explore the solar corona by performing in-situ measurements at distances as close as four solar radii or 0.02 AU from the sun. This proximity to the sun imposes some unusual design constraints on the RTG and on its integration with the spacecraft. The results demonstrated that the obstructions result in significant performance penalties for the case of the standard GPHS-RTG design. Finally, the paper describes a simple empirical method for predicting the combined effect of fuel decay and thermoelectric degradation on the RTG's power output, and applies that method to predict the long-term power profile of the obstructed Solar Probe RTGs. The results indicate that the existing GPHS-RTG design, even without modifications can meet the JPL-prescribed EOM power requirement. There is also three copies in the file of an earlier version of this dated 8/3/1990 with the report number of FSC-ESD-217-90-470. The most current one is the IAF version (IAD-90-208) dated October 6-12, 1990.

  1. Up on the Roof: A Systematic Approach to Roof Maintenance.

    ERIC Educational Resources Information Center

    Burd, William

    1979-01-01

    A systematic roof maintenance program is characterized by carefully prepared long- and short-range plans. An essential feature of a systematic approach to roof maintenance is the stress on preventive measures rather than the patching of leaks. (Author)

  2. ROOF, A view looking north from the stair tower roof ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    ROOF, A view looking north from the stair tower roof at the external piping - Department of Energy, Mound Facility, Hydrolysis House Building (HH Building), One Mound Road, Miamisburg, Montgomery County, OH

  3. Rod shop, roof and truss detail showing older pink roof ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Rod shop, roof and truss detail showing older pink roof truss, newer pratt truss, and longitudinal, truss for overhead traveling crane - Chicago, Burlington & Quincy Railroad, Roundhouse & Shops, Broadway & Spring Streets, Aurora, Kane County, IL

  4. Detail view, roofing material removed from firedamaged roof and placed ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail view, roofing material removed from fire-damaged roof and placed on lawn to the east of biddle hall. - U. S. Naval Asylum, Biddle Hall, Gray's Ferry Avenue, Philadelphia, Philadelphia County, PA

  5. 77 FR 32698 - Proposed Extension of Existing Information Collection; Safety Standards for Roof Bolts in Metal...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-01

    ... given operation at any given time. Roof and rock bolts and accessories are an integral part of ground... technology of roof and rock bolts and accessories have aided in reducing the hazards associated with falls of....3203 Rock fixtures Sec. 57.3203 Rock fixtures Sec. 75.204(a) & (f)(6) Roof bolting II. Desired Focus...

  6. 76 FR 69284 - Certain Integrated Solar Power Systems and Components Thereof: Notice of Institution of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-08

    ... COMMISSION Certain Integrated Solar Power Systems and Components Thereof: Notice of Institution of....S.C. 1337, on behalf of Westinghouse Solar, Inc. of Campbell, California and Andalay Solar, Inc. of... importation, and the sale within the United States after importation of certain integrated solar power...

  7. A window to the future: Building-integrated photovoltaics

    SciTech Connect

    Strong, S.J.

    1998-01-01

    Building integrated photovoltaic systems (BIPS) incorporate solar electric cells into building envelope materials, creating attractive, economical and environmentally benign power resources for buildings. This article discusses design and implementation of these systems. Topics include markets, development and design of BIPV oriented buildings, modules, solar roofs, and a summary of the future.

  8. Waste and Abuse: Public School Roofing Projects.

    ERIC Educational Resources Information Center

    2000

    This report details the results of a comprehensive inquiry by New Jersey into one aspect of school construction, the repair and replacement of roof systems, which represents the single most expensive and integral component of a school's physical structure. The investigation began in late 1997 after confidential complaints suggested abuse in the…

  9. Western Wind and Solar Integration Study Phase 2: Preprint

    SciTech Connect

    Lew, D.; Brinkman, G.; Ibanez, E.; Hodge, B.-M.; King, J.

    2012-09-01

    The Western Wind and Solar Integration Study (WWSIS) investigates the impacts of high penetrations of wind and solar power into the Western Interconnection of the United States. WWSIS2 builds on the Phase 1 study but with far greater refinement in the level of data inputs and production simulation. It considers the differences between wind and solar power on systems operations. It considers mitigation options to accommodate wind and solar when full costs of wear-and-tear and full impacts of emissions rates are taken into account. It determines wear-and-tear costs and emissions impacts. New data sets were created for WWSIS2, and WWSIS1 data sets were refined to improve realism of plant output and forecasts. Four scenarios were defined for WWSIS2 that examine the differences between wind and solar and penetration level. Transmission was built out to bring resources to load. Statistical analysis was conducted to investigate wind and solar impacts at timescales ranging from seasonal down to 5 minutes.

  10. Integrated thin film cadmium sulfide solar cell module

    NASA Technical Reports Server (NTRS)

    Mickelsen, R. A.; Abbott, D. D.

    1971-01-01

    The design, development, fabrication and tests of flexible integrated thin-film cadmium sulfide solar cells and modules are discussed. The development of low cost and high production rate methods for interconnecting cells into large solar arrays is described. Chromium thin films were applied extensively in the deposited cell structures as a means to: (1) achieve high adherence between the cadmium sulfide films and the vacuum-metallized copper substrates, (2) obtain an ohmic contact to the cadmium sulfide films, and (3) improve the adherence of gold films as grids or contact areas.

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

    NASA Astrophysics Data System (ADS)

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

    2014-07-01

    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.

  12. Hygrothermal Performance of West Coast Wood Deck Roofing System

    SciTech Connect

    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.

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

    SciTech Connect

    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.

  14. Roofing: Workbook and Tests. Built-up Roofing.

    ERIC Educational Resources Information Center

    Klingensmith, Robert, Ed.

    Designed for use in roofing apprenticeship classes, this workbook contains eight units on skills used in built-up roofing, a listing of instructional materials, a glossary, and the text of Labor Code Article 30, Construction Safety Orders, "Roofing Operations and Equipment." Each instructional unit includes a listing of performance statements and…

  15. 24. Roof detail from liftbed truck, showing pan roof above ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. Roof detail from lift-bed truck, showing pan roof above breezeway, with sawn redwood trim, tube-type drains; note missing rain gutter at roof edge, deteriorated condition of slates; view to south, 90mm lens. - Southern Pacific Depot, 559 El Camino Real, San Carlos, San Mateo County, CA

  16. Operation of Concentrating Solar Power Plants in the Western Wind and Solar Integration Phase 2 Study

    SciTech Connect

    Denholm, P.; Brinkman, G.; Lew, D.; Hummon, M.

    2014-05-01

    The Western Wind and Solar Integration Study (WWSIS) explores various aspects of the challenges and impacts of integrating large amounts of wind and solar energy into the electric power system of the West. The phase 2 study (WWSIS-2) is one of the first to include dispatchable concentrating solar power (CSP) with thermal energy storage (TES) in multiple scenarios of renewable penetration and mix. As a result, it provides unique insights into CSP plant operation, grid benefits, and how CSP operation and configuration may need to change under scenarios of increased renewable penetration. Examination of the WWSIS-2 results indicates that in all scenarios, CSP plants with TES provides firm system capacity, reducing the net demand and the need for conventional thermal capacity. The plants also reduced demand during periods of short-duration, high ramping requirements that often require use of lower efficiency peaking units. Changes in CSP operation are driven largely by the presence of other solar generation, particularly PV. Use of storage by the CSP plants increases in the higher solar scenarios, with operation of the plant often shifted to later in the day. CSP operation also becomes more variable, including more frequent starts. Finally, CSP output is often very low during the day in scenarios with significant PV, which helps decrease overall renewable curtailment (over-generation). However, the configuration studied is likely not optimal for High Solar Scenario implying further analysis of CSP plant configuration is needed to understand its role in enabling high renewable scenarios in the Western United States.

  17. Hawaii Solar Integration Study: Solar Modeling Developments and Study Results; Preprint

    SciTech Connect

    Orwig, K.; Corbus, D.; Piwko, R.; Schuerger, M.; Matsuura, M.; Roose, L.

    2012-12-01

    The Hawaii Solar Integration Study (HSIS) is a follow-up to the Oahu Wind Integration and Transmission Study completed in 2010. HSIS focuses on the impacts of higher penetrations of solar energy on the electrical grid and on other generation. HSIS goes beyond the island of Oahu and investigates Maui as well. The study examines reserve strategies, impacts on thermal unit commitment and dispatch, utilization of energy storage, renewable energy curtailment, and other aspects of grid reliability and operation. For the study, high-frequency (2-second) solar power profiles were generated using a new combined Numerical Weather Prediction model/ stochastic-kinematic cloud model approach, which represents the 'sharp-edge' effects of clouds passing over solar facilities. As part of the validation process, the solar data was evaluated using a variety of analysis techniques including wavelets, power spectral densities, ramp distributions, extreme values, and cross correlations. This paper provides an overview of the study objectives, results of the solar profile validation, and study results.

  18. Green Roofs for Stormwater Runoff Control - Abstract

    EPA Science Inventory

    This project evaluated green roofs as a stormwater management tool. Specifically, runoff quantity and quality from green and flat asphalt roofs were compared. Evapotranspiration from planted green roofs and evaporation from unplanted media roofs were also compared. The influence...

  19. High-Tech Roof Management.

    ERIC Educational Resources Information Center

    Benzie, Tim

    1997-01-01

    Describes the use of a computerized roof management system (CRMS) for school districts to foster multiple roof maintenance efficiency and cost effectiveness. Highlights CRMS software manufacturer choices, as well as the types of nondestructive testing equipment tools that can be used to evaluate roof conditions. (GR)

  20. ROOFING, PART I. WORKBOOK.

    ERIC Educational Resources Information Center

    FREDRICKS, JOHN; AND OTHERS

    THE TECHNICAL INFORMATION IN THIS STUDY GUIDE WAS DEVELOPED FOR USE IN RELATED INSTRUCTION IN APPRENTICE TRAINING PROGRAMS FOR ROOFERS. THE MATERIAL WAS PLANNED UNDER THE DIRECTION OF THE STATE EDUCATIONAL ADVISORY COMMITTEE FOR THE ROOFING TRADE AND PREPARED UNDER DIRECTION OF THE BUREAU OF INDUSTRIAL EDUCATION. THE UNITS ARE (1) THE APPRENTICE…

  1. Large Scale Wind and Solar Integration in Germany

    SciTech Connect

    Ernst, Bernhard; Schreirer, Uwe; Berster, Frank; Pease, John; Scholz, Cristian; Erbring, Hans-Peter; Schlunke, Stephan; Makarov, Yuri V.

    2010-02-28

    This report provides key information concerning the German experience with integrating of 25 gigawatts of wind and 7 gigawatts of solar power capacity and mitigating its impacts on the electric power system. The report has been prepared based on information provided by the Amprion GmbH and 50Hertz Transmission GmbH managers and engineers to the Bonneville Power Administration (BPA) and Pacific Northwest National Laboratory representatives during their visit to Germany in October 2009. The trip and this report have been sponsored by the BPA Technology Innovation office. Learning from the German experience could help the Bonneville Power Administration engineers to compare and evaluate potential new solutions for managing higher penetrations of wind energy resources in their control area. A broader dissemination of this experience will benefit wind and solar resource integration efforts in the United States.

  2. Structural assessment of roof decking using visual inspection methods

    SciTech Connect

    Giller, R.A.; McCoy, R.M.; Wagenblast, G.R.

    1993-10-01

    The Hanford Site has approximately 1,100 buildings, some of which date back to the early 1940s. The roof on these buildings provides a weather resisting cover as well as the load resisting structure. Past experience has been that these roof structures may have structural modifications, the weather resisting membrane may have been replaced several times, and the members may experience some type of material degradation. This material degradation has progressed to cause the collapse of some roof deck members. The intent of the Hanford Site Central Engineering roof assessment effort is to provide an expedient structural assessment of the large number of buildings at the Hanford Site. This assessment is made by qualified structural inspectors following the {open_quotes}Preliminary Assessment{close_quote} procedures given in the American Society of Civil Engineers (ASCE) Standard ASCE 11-90. This roof assessment effort does not provide a total qualification of the roof for the design or in-place loads. This inspection does provide a reasonable estimate of the roof loading capacity to determine if personnel access restrictions are needed. A document search and a visual walkdown inspection provide the initial screening to identify modifications and components having questionable structural integrity. The structural assessment consists of baseline dead and live load stress calculations of all roofing components based on original design material strengths. The results of these assessments are documented in a final report which is retrievable form that future inspections will have comparative information.

  3. Design of nonimaging static solar concentrator for window integrated photovoltaic

    NASA Astrophysics Data System (ADS)

    Sellami, Nazmi; Mallick, Tapas K.

    2012-10-01

    The focus of this research is to develop a solar concentrator for the purpose of building integration which is compact, static and, at the same time, able to collect maximum solar energy. The novel concentrator is designed to be used in Window Integrated Concentrated PV (WICPV). The window provides natural light transmission as well as electricity production. The concentrator is optically optimised for different incident angles of the incoming light rays. Evaluating the best combination of the optical efficiency and the acceptance angle, the 4x concentrator built from dielectric material, working with total internal reflection is optimised. It is found to have a constant optical efficiency of 40% for an acceptance angle equal to 120° (-60°, +60°) and an optical concentration ratio (OCR) of 1.6x. This enables capture of the sun rays all day long from both direct and diffuse light. Higher OCR's are obtained for different dimensions of the solar concentrator; however, the acceptance angles are relatively low. Three prototypes with different heights (10mm, 15mm and 20 mm) of the optimised concentrators have been manufactured and tested in indoor conditions. The experimental results validate the results obtained from the optical model with a variation of less than 5%.

  4. Aging and weathering of cool roofing membranes

    SciTech Connect

    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.

  5. Producing superhydrophobic roof tiles.

    PubMed

    Carrascosa, Luis A M; Facio, Dario S; Mosquera, Maria J

    2016-03-01

    Superhydrophobic materials can find promising applications in the field of building. However, their application has been very limited because the synthesis routes involve tedious processes, preventing large-scale application. A second drawback is related to their short-term life under outdoor conditions. A simple and low-cost synthesis route for producing superhydrophobic surfaces on building materials is developed and their effectiveness and their durability on clay roof tiles are evaluated. Specifically, an organic-inorganic hybrid gel containing silica nanoparticles is produced. The nanoparticles create a densely packed coating on the roof tile surface in which air is trapped. This roughness produces a Cassie-Baxter regime, promoting superhydrophobicity. A surfactant, n-octylamine, was also added to the starting sol to catalyze the sol-gel process and to coarsen the pore structure of the gel network, preventing cracking. The application of ultrasound obviates the need to use volatile organic compounds in the synthesis, thereby making a 'green' product. It was also demonstrated that a co-condensation process effective between the organic and inorganic species is crucial to obtain durable and effective coatings. After an aging test, high hydrophobicity was maintained and water absorption was completely prevented for the roof tile samples under study. However, a transition from a Cassie-Baxter to a Wenzel state regime was observed as a consequence of the increase in the distance between the roughness pitches produced by the aging of the coating. PMID:26854839

  6. Producing superhydrophobic roof tiles

    NASA Astrophysics Data System (ADS)

    Carrascosa, Luis A. M.; Facio, Dario S.; Mosquera, Maria J.

    2016-03-01

    Superhydrophobic materials can find promising applications in the field of building. However, their application has been very limited because the synthesis routes involve tedious processes, preventing large-scale application. A second drawback is related to their short-term life under outdoor conditions. A simple and low-cost synthesis route for producing superhydrophobic surfaces on building materials is developed and their effectiveness and their durability on clay roof tiles are evaluated. Specifically, an organic-inorganic hybrid gel containing silica nanoparticles is produced. The nanoparticles create a densely packed coating on the roof tile surface in which air is trapped. This roughness produces a Cassie-Baxter regime, promoting superhydrophobicity. A surfactant, n-octylamine, was also added to the starting sol to catalyze the sol-gel process and to coarsen the pore structure of the gel network, preventing cracking. The application of ultrasound obviates the need to use volatile organic compounds in the synthesis, thereby making a ‘green’ product. It was also demonstrated that a co-condensation process effective between the organic and inorganic species is crucial to obtain durable and effective coatings. After an aging test, high hydrophobicity was maintained and water absorption was completely prevented for the roof tile samples under study. However, a transition from a Cassie-Baxter to a Wenzel state regime was observed as a consequence of the increase in the distance between the roughness pitches produced by the aging of the coating.

  7. Mission applications of an Integrated Solar Upper Stage (ISUS)

    SciTech Connect

    Kennedy, F.G. III; Jacox, M.G.

    1995-12-31

    The Integrated Solar Upper Stage (ISUS) Program at the US Air Force`s Phillips Laboratory is directing its efforts to solving endemic national spacelift architecture problems. Air Force Space Command has called spacelift both unaffordable and nonresponsive; today`s space launch systems are descendants of 1950`s era ICBM technologies and require prolonged on-pad processing. Advanced propulsion techniques, reusability, and modular architectures have not been generally incorporated into US systems. The ISUS system is an advanced, integrated upper stage concept that would permit payload realignment, allowing large payloads to be moved to smaller, less expensive boosters; such realignment both reduces cost and enhances responsiveness, as smaller boosters cost less to launch and require less vehicle and payload processing time. Three ISUS operational concepts are discussed, allowing the realignment of payloads currently launched aboard Titan IV/Centaur, Atlas IIAS, and Delta 2. A space demonstration of ISUS is examined. The Integrated Solar Upper Stage is a single piece of hardware that provides electric power and orbit transfer propulsion to a spacecraft. There are three major subsystems that comprise the ISUS; the receiver/absorber/converter or RAC, the concentrators, and the hydrogen tankage and feed subsystem.

  8. Thermionic converters for an Integrated Solar Upper Stage (ISUS)

    SciTech Connect

    Anderson, W.G.; Horner-Richardson, K.

    1996-12-31

    The Integrated Solar Upper Stage (ISUS) is a solar bimodal system which combines thermal propulsion and electric power generation in a single integrated system. A thermionic converter was designed and fabricated for the ISUS system. The ISUS thermionic energy converters differ from previous designs, due to the significant changes in operating temperature prior to and during an eclipse, with the emitter temperature increasing from 1,900 K to 2,200 K, and then back again. A complete thermal and electrical model was developed for a planar diode to determine optimum operating dimensions and parameters. The model includes an overall energy balance for the diode, and changes the interelectrode gap spacing due to thermal expansion of the parts as the emitter and/or collector temperatures change. Cesium pressure can be chosen from an external liquid reservoir, an integral reservoir using cesium intercalated into graphite attached to the collector heat pipe, or optimum cesium pressure. With optimum cesium pressure, the maximum efficiency increases from 14% to 16% as the emitter temperature increases from 1,900 K to 2,200 K. The improvement in efficiency is only 2% as the emitter temperature is increased. Optimum efficiency requires an external, actively controlled liquid reservoir.

  9. Effects of white roofs on urban temperature in a global climate model

    NASA Astrophysics Data System (ADS)

    Oleson, K. W.; Bonan, G. B.; Feddema, J.

    2010-02-01

    Increasing the albedo of urban surfaces has received attention as a strategy to mitigate urban heat islands. Here, the effects of globally installing white roofs are assessed using an urban canyon model coupled to a global climate model. Averaged over all urban areas, the annual mean heat island decreased by 33%. Urban daily maximum temperature decreased by 0.6C and daily minimum temperature by 0.3C. Spatial variability in the heat island response is caused by changes in absorbed solar radiation and specification of roof thermal admittance. At high latitudes in winter, the increase in roof albedo is less effective at reducing the heat island due to low incoming solar radiation, the high albedo of snow intercepted by roofs, and an increase in space heating that compensates for reduced solar heating. Global space heating increased more than air conditioning decreased, suggesting that end-use energy costs must be considered in evaluating the benefits of white roofs.

  10. Stormwater Attenuation by Green Roofs

    NASA Astrophysics Data System (ADS)

    Sims, A.; O'Carroll, D. M.; Robinson, C. E.; Smart, C. C.

    2014-12-01

    Innovative municipal stormwater management technologies are urgently required in urban centers. Inadequate stormwater management can lead to excessive flooding, channel erosion, decreased stream baseflows, and degraded water quality. A major source of urban stormwater is unused roof space. Green roofs can be used as a stormwater management tool to reduce roof generated stormwater and generally improve the quality of runoff. With recent legislation in some North American cities, including Toronto, requiring the installation of green roofs on large buildings, research on the effectiveness of green roofs for stormwater management is important. This study aims to assess the hydrologic response of an extensive sedum green roof in London, Ontario, with emphasis on the response to large precipitation events that stress municipal stormwater infrastructure. A green roof rapidly reaches field capacity during large storm events and can show significantly different behavior before and after field capacity. At field capacity a green roof has no capillary storage left for retention of stormwater, but may still be an effective tool to attenuate peak runoff rates by transport through the green roof substrate. The attenuation of green roofs after field capacity is linked to gravity storage, where gravity storage is the water that is temporarily stored and can drain freely over time after field capacity has been established. Stormwater attenuation of a modular experimental green roof is determined from water balance calculations at 1-minute intervals. Data is used to evaluate green roof attenuation and the impact of field capacity on peak flow rates and gravity storage. In addition, a numerical model is used to simulate event based stormwater attenuation. This model is based off of the Richards equation and supporting theory of multiphase flow through porous media.

  11. Integrated Solar-Energy-Harvesting and -Storage Device

    NASA Technical Reports Server (NTRS)

    whitacre, Jay; Fleurial, Jean-Pierre; Mojarradi, Mohammed; Johnson, Travis; Ryan, Margaret Amy; Bugga, Ratnakumar; West, William; Surampudi, Subbarao; Blosiu, Julian

    2004-01-01

    A modular, integrated, completely solid-state system designed to harvest and store solar energy is under development. Called the power tile, the hybrid device consists of a photovoltaic cell, a battery, a thermoelectric device, and a charge-control circuit that are heterogeneously integrated to maximize specific energy capacity and efficiency. Power tiles could be used in a variety of space and terrestrial environments and would be designed to function with maximum efficiency in the presence of anticipated temperatures, temperature gradients, and cycles of sunlight and shadow. Because they are modular in nature, one could use a single power tile or could construct an array of as many tiles as needed. If multiple tiles are used in an array, the distributed and redundant nature of the charge control and distribution hardware provides an extremely fault-tolerant system. The figure presents a schematic view of the device.

  12. Demonstration of Cooling Savings of Light Colored Roof Surfacing in Florida Commercial Buildings: Our Savior's School.

    ERIC Educational Resources Information Center

    Parker, Danny S.; Sherwin, John R.; Sonne, Jeffrey K.; Barkaszi, Stephen F., Jr.

    A 2-year Florida study attempted to quantify air conditioning cost savings when buildings have a white reflective roof. A 10,000 square foot elementary school with a gray modified bitumen roof over plywood decking that had a solar reflectance of 23 percent was monitored for an entire year. After one year of building thermal conditions and…

  13. Western Wind and Solar Integration Study: Hydropower Analysis

    SciTech Connect

    Acker, T.; Pete, C.

    2012-03-01

    The U.S. Department of Energy's (DOE) study of 20% Wind Energy by 2030 was conducted to consider the benefits, challenges, and costs associated with sourcing 20% of U.S. energy consumption from wind power by 2030. This study found that with proactive measures, no insurmountable barriers were identified to meet the 20% goal. Following this study, DOE and the National Renewable Energy Laboratory (NREL) conducted two more studies: the Eastern Wind Integration and Transmission Study (EWITS) covering the eastern portion of the U.S., and the Western Wind and Solar Integration Study (WWSIS) covering the western portion of the United States. The WWSIS was conducted by NREL and research partner General Electric (GE) in order to provide insight into the costs, technical or physical barriers, and operational impacts caused by the variability and uncertainty of wind, photovoltaic, and concentrated solar power when employed to serve up to 35% of the load energy in the WestConnect region (Arizona, Colorado, Nevada, New Mexico, and Wyoming). WestConnect is composed of several utility companies working collaboratively to assess stakeholder and market needs to and develop cost-effective improvements to the western wholesale electricity market. Participants include the Arizona Public Service, El Paso Electric Company, NV Energy, Public Service of New Mexico, Salt River Project, Tri-State Generation and Transmission Cooperative, Tucson Electric Power, Xcel Energy and the Western Area Power Administration.

  14. Entering the Roofing and Waterproofing Industry. Roofing Workbook and Tests.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento. Bureau of Publications.

    This book is one of a series of 10 units of instruction for roofing apprenticeship classes in California. It covers the following 14 topics and provides tests for them: the nature of the roofing and waterproofing industry; the apprenticeship program; apprenticeship and the public schools; collective bargaining, wages, and benefits; safety in the…

  15. 13. ONE OF TWO LATERAL ROOF TRUSSES AND ROOF SUPPORT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. ONE OF TWO LATERAL ROOF TRUSSES AND ROOF SUPPORT BEAMS OF SARATOGA GAS LIGHT COMPANY GASHOLDER NO. 2 HOUSE LOOKING WEST. THE WIRES AND BEAM AT RIGHT CENTER OF PHOTOGRAPH HAVE BEEN ADDED TO STABILIZE TRUSS SYSTEM - Saratoga Gas Light Company, Gasholder No. 2, Niagara Mohawk Power Corporation Substation Facility, intersection of Excelsior & East Avenues, Saratoga Springs, NY

  16. 12. CENTRAL ROOF TRUSS AND ROOF SUPPORT BEAMS OF SARATOGA ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. CENTRAL ROOF TRUSS AND ROOF SUPPORT BEAMS OF SARATOGA GAS LIGHT COMPANY GASHOLDER NO. 2 HOUSE, LOOKING WEST. THE WIRES AND BEAM AT RIGHT OF PHOTOGRAPH HAVE BEEN ADDED TO STABILIZE TRUSS SYSTEM. - Saratoga Gas Light Company, Gasholder No. 2, Niagara Mohawk Power Corporation Substation Facility, intersection of Excelsior & East Avenues, Saratoga Springs, NY

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

    SciTech Connect

    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.

  18. Preventive Maintenance the Key to Preserving Roofing.

    ERIC Educational Resources Information Center

    Napier, Robert Jon; Ephron, Hazel

    1990-01-01

    Roof maintenance and repair should be part of an ongoing preservation program. Describes New York's Capital Assets Preservation (CAP) program and includes a CAP checklist and criteria for evaluating a roofing system. Describes roof testing methods. (MLF)

  19. Solar energy grid integration systems : final report of the Florida Solar Energy Center Team.

    SciTech Connect

    Ropp, Michael; Gonzalez, Sigifredo; Schaffer, Alan; Katz, Stanley; Perkinson, Jim; Bower, Ward Isaac; Prestero, Mark; Casey, Leo; Moaveni, Houtan; Click, David; Davis, Kristopher; Reedy, Robert; Kuszmaul, Scott S.; Sena-Henderson, Lisa; David, Carolyn; Akhil, Abbas Ali

    2012-03-01

    Initiated in 2008, the Solar Energy Grid Integration Systems (SEGIS) program is a partnership involving the U.S. DOE, Sandia National Laboratories, private sector companies, electric utilities, and universities. Projects supported under the program have focused on the complete-system development of solar technologies, with the dual goal of expanding utility-scale penetration and addressing new challenges of connecting large-scale solar installations in higher penetrations to the electric grid. The Florida Solar Energy Center (FSEC), its partners, and Sandia National Laboratories have successfully collaborated to complete the work under the third and final stage of the SEGIS initiative. The SEGIS program was a three-year, three-stage project that include conceptual design and market analysis in Stage 1, prototype development and testing in Stage 2, and moving toward commercialization in Stage 3. Under this program, the FSEC SEGIS team developed a comprehensive vision that has guided technology development that sets one methodology for merging photovoltaic (PV) and smart-grid technologies. The FSEC team's objective in the SEGIS project is to remove barriers to large-scale general integration of PV and to enhance the value proposition of photovoltaic energy by enabling PV to act as much as possible as if it were at the very least equivalent to a conventional utility power plant. It was immediately apparent that the advanced power electronics of these advanced inverters will go far beyond conventional power plants, making high penetrations of PV not just acceptable, but desirable. This report summarizes a three-year effort to develop, validate and commercialize Grid-Smart Inverters for wider photovoltaic utilization, particularly in the utility sector.

  20. GAISUS-1 thermionic converter for the integrated solar upper stage

    SciTech Connect

    Begg, L.L.; Heffernan, T.F.; Horner, M.H.

    1997-12-31

    The Integrated Solar Upper Stage (ISUS) system is a compact orbital transfer vehicle which generates thrust to boost payloads from LEO to higher orbits. It does this by collecting and concentrating solar flux into a sensible thermal storage, graphite receiver which is used to heat hydrogen propellant to temperatures of up to 2500 K. The ISUS receiver also radiates heat into an array of thermionic converters which produce electrical power. The GAISUS-1 thermionic converter is a first generation planar converter designed to produce electrical power when coupled with the ISUS receiver. GAISUS-1 will deliver over 31 W{sub e} at 1900 K. A wrought Re hotshoe accepts radiant heat from the receiver. The back side of the hotshoe forms the emitting surface of the converter. Special attention was paid to optimize the electrical and thermal losses experienced through the sleeve. Triple and single sleeve geometries were thermally modeled and evaluated, resulting in the selection of a single sleeve design. A high temperature metal/ceramic seal isolates the emitter sleeve from the collector. A Nb collector is used and is an integral part of a Nb/Na heat pipe. The heat pipe transports reject heat from the collector surface to a thermal radiator (condenser) portion of the heat pipe. The converter utilizes an integral graphite Cs reservoir. This type of reservoir automatically produces a rise in Cs pressure in response to a rise in emitter/collector temperatures. This Cs pressure feedback mechanism insures adequate Cs coverage of the emitter over a broad range of operating conditions (temperatures).

  1. How Cool Is Your Roof?

    ERIC Educational Resources Information Center

    Fickes, Michael

    2001-01-01

    Explains a concept called cool roof that is used to reduce electricity costs for air conditioning, and also reduce the price of air conditioning units. Discusses the light reflecting capabilities of metal roofing as well as coatings that can stop leaks. (GR)

  2. Energy Performance Impacts from Competing Low-slope Roofing Choices and Photovoltaic Technologies

    NASA Astrophysics Data System (ADS)

    Nagengast, Amy L.

    With such a vast quantity of space, commercial low-slope roofs offer significant potential for sustainable roofing technology deployment. Specifically, building energy performance can be improved by installing rooftop energy technologies such as photovoltaic (PV) panels, and/or including designs such as white or green roofs instead of traditional black. This research aims to inform and support roof decisions through quantified energy performance impacts across roof choices and photovoltaic technologies. The primary dataset for this research was measured over a 16 month period (May 24, 2011 to October 13, 2012) from a large field experiment in Pittsburgh, Pennsylvania on top of a commercial warehouse with white, black and green roof sections, each with portions covered by polycrystalline photovoltaic panels. Results from the Pittsburgh experiment were extended to three different cities (San Diego, CA; Huntsville, AL; and Phoenix, AZ) chosen to represent a wide range of irradiance and temperature values. First, this research evaluated the difference in electricity production from a green-moss roof and black roof underneath photovoltaic panels to determine if the green roof's cooler air increases the panel efficiency. Second, separate studies examine 1) average hourly heat flux by month for unobstructed and shaded roof membranes 2) heat flux peak time delay, and 3) air temperature across roof types. Results of this research show green roofs slightly increased (0.8-1.5%) PV panel efficiency in temperatures approximately at or above 25° C (77°F) compared to black roofs. However in cool climates, like Pittsburgh, the roof type under the PV panels had little overall impact on PV performance when considering year round temperatures. Instead, roof decisions should place a stronger emphasis on heat flux impacts. The green roof outperformed both black and white roofs at minimizing total conductive heat flux. These heat flow values were used to develop a new, straight-forward methodology to roughly estimate heat flux impacts of different roof types in other climates using ambient temperature and solar irradiance. While managing heat flow is important for building energy performance, roof choices need to include a systems level analysis encompassing a year for the specific region to best quantify the overall energy impacts.

  3. NREL Analysis: Cost-Effective and Reliable Integration of High-Penetration Solar in the Western United States (Poster)

    SciTech Connect

    Lew, D.; Brinkman, G.; Ibanez, E.; Hodge, B.; Lefton, S.; Kumar, N.; Agan, D.; Jordan, G.; Venkatataman, S.

    2012-07-01

    SunShot Initiative awardee posters describing the different technologies within the four subprograms of the DOE Solar Program (Photovoltaics, Concentrating Solar Power, Soft Costs, and Systems Integration).

  4. Measuring mine roof bolt strains

    DOEpatents

    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.

  5. The impact of roofing material on building energy performance

    NASA Astrophysics Data System (ADS)

    Badiee, Ali

    The last decade has seen an increase in the efficient use of energy sources such as water, electricity, and natural gas as well as a variety of roofing materials, in the heating and cooling of both residential and commercial infrastructure. Oil costs, coal and natural gas prices remain high and unstable. All of these instabilities and increased costs have resulted in higher heating and cooling costs, and engineers are making an effort to keep them under control by using energy efficient building materials. The building envelope (that which separates the indoor and outdoor environments of a building) plays a significant role in the rate of building energy consumption. An appropriate architectural design of a building envelope can considerably lower the energy consumption during hot summers and cold winters, resulting in reduced HVAC loads. Several building components (walls, roofs, fenestration, foundations, thermal insulation, external shading devices, thermal mass, etc.) make up this essential part of a building. However, thermal insulation of a building's rooftop is the most essential part of a building envelope in that it reduces the incoming "heat flux" (defined as the amount of heat transferred per unit area per unit time from or to a surface) (Sadineni et al., 2011). Moreover, more than 60% of heat transfer occurs through the roof regardless of weather, since a roof is often the building surface that receives the largest amount of solar radiation per square annually (Suman, and Srivastava, 2009). Hence, an argument can be made that the emphasis on building energy efficiency has influenced roofing manufacturing more than any other building envelope component. This research project will address roofing energy performance as the source of nearly 60% of the building heat transfer (Suman, and Srivastava, 2009). We will also rank different roofing materials in terms of their energy performance. Other parts of the building envelope such as walls, foundation, fenestration, etc. and their thermal insulation energy performance value will not be included this study. Five different UAB campus buildings with the same reinforced concrete structure (RC Structure), each having a different roofing material were selected, surveyed, analyzed, and evaluated in this study. Two primary factors are considered in this evaluation: the energy consumption and utility bills. The data has been provided by the UAB Facilities Management Department and has been monitored from 2007 to 2013 using analysis of variance (ANOVA) and t-test methods. The energy utilities examined in this study involved electricity, domestic water, and natural gas. They were measured separately in four different seasons over a seven-year time period. The building roofing materials consisted of a green roof, a white (reflective) roof, a river rock roof, a concrete paver roof, and a traditional black roof. Results of the tested roofs from this study indicate that the white roof is the most energy efficient roofing material.

  6. Installation package for integrated programmable electronic controller and hydronic subsystem - solar heating and cooling

    NASA Technical Reports Server (NTRS)

    1978-01-01

    A description is given of the Installation, Operation, and Maintenance Manual and information on the power panel and programmable microprocessor, a hydronic solar pump system and a hydronic heating hot water pumping system. These systems are integrated into various configurations for usages in solar energy management, control and monitoring, lighting control, data logging and other solar related applications.

  7. 77 FR 39736 - Certain Integrated Solar Power Systems and Components Thereof; Notice of Termination of the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-05

    ... reason of infringement of certain claims of U.S. Patent Nos. 7,406,800 and 7,987,641. 76 FR 69284 (Nov. 8... COMMISSION Certain Integrated Solar Power Systems and Components Thereof; Notice of Termination of the..., 2011, based on a complaint filed by Westinghouse Solar, Inc. and Andalay Solar, Inc., both of...

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

    SciTech Connect

    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).

  9. Lightweight, Flexible, Thin, Integrated Solar-Power Packs

    NASA Technical Reports Server (NTRS)

    Hanson, Robert R.

    2004-01-01

    Lightweight, flexible, thin, one-piece, solar-power packs are undergoing development. Each power pack of this type is a complete, modular, integrated power-supply system comprising three power subsystems that, in conventional practice, have been constructed as separate units and connected to each other by wires. These power packs are amenable to a variety of uses: For example, they could be laminated to the tops of tents and other shelters to provide or augment power for portable electronic equipment in the field, and they could be used as power sources for such small portable electronic systems as radio transceivers (including data relays and cellular telephones), laptop computers, video camcorders, and Global Positioning System receivers.

  10. Western Wind and Solar Integration Study Phase 2 (Presentation)

    SciTech Connect

    Lew, D.; Brinkman, G.; Ibanez, E.; Kumar, N.; Lefton, S.; Jordan, G.; Venkataraman, S.; King, J.

    2013-06-01

    This presentation accompanies Phase 2 of the Western Wind and Solar Integration Study, a follow-on to Phase 1, which examined the operational impacts of high penetrations of variable renewable generation on the electric power system in the West and was one of the largest variable generation studies to date. High penetrations of variable generation can induce cycling of fossil-fueled generators. Cycling leads to wear-and-tear costs and changes in emissions. Phase 2 calculated these costs and emissions, and simulated grid operations for a year to investigate the detailed impact of variable generation on the fossil-fueled fleet. The presentation highlights the scope of the study and results.

  11. Solar energy grid integration systems - Energy storage (SEGIS-ES)

    SciTech Connect

    Ton, Dan; Peek, Georgianne H.; Hanley, Charles; Boyes, John

    2008-05-01

    In late 2007, the U.S. Department of Energy (DOE) initiated a series of studies to address issues related to potential high penetration of distributed photovoltaic (PV) generation systems on our nation’s electric grid. This Renewable Systems Interconnection (RSI) initiative resulted in the publication of 14 reports and an Executive Summary that defined needs in areas related to utility planning tools and business models, new grid architectures and PV systems configurations, and models to assess market penetration and the effects of high-penetration PV systems. As a result of this effort, the Solar Energy Grid Integration Systems (SEGIS) program was initiated in early 2008. SEGIS is an industry-led effort to develop new PV inverters, controllers, and energy management systems that will greatly enhance the utility of distributed PV systems.

  12. Monte Carlo Simulations of Luminescent Solar Concentrators with Front-Facing Photovoltaic Cells for Building Integrated Photovoltaics

    NASA Astrophysics Data System (ADS)

    Leow, Shin; Corrado, Carley; Osborn, Melissa; Carter, Sue

    2013-03-01

    Luminescent solar concentrators (LSCs) have the ability to receive light from a wide range of angles and concentrate the captured light on to small photo active areas. This enables LSCs to be integrated more extensively into buildings as windows and wall claddings on top of roof installations. LSCs with front facing PV cells collect both direct and concentrated light ensuring a gain factor greater than one. It also allows for flexibility in determining the placement and percentage coverage of PV cells when designing panels to balance reabsorption losses, power output and the level of concentration desired. A Monte-Carlo ray tracing program was developed to study the transport of photons and loss mechanisms in LSC panels and aid in design optimization. The program imports measured absorption/emission spectra and transmission coefficients as simulation parameters. Interactions of photons with the LSC panel are determined by comparing calculated probabilities with random number generators. Simulation results reveal optimal panel dimensions and PV cell layouts to achieve maximum power output.

  13. Roof control strategies for underground coal mines

    SciTech Connect

    Smith, W.C. )

    1993-01-01

    Roof support, an important aspect of ground control, involves maintaining roof competency to ensure a safe and efficient mining environment. Wide variability in rock quality and stress distributions requires a systematic approach to roof support design that satisfies specific goals. The success of past roof support in reducing the incidence of roof falls has been primarily attributed to safer roof bolting practices. However, roof falls continue to be the number one occupational hazard in underground coal mines. This US Bureau of Mines report presents a general overview of roof bolting and other roof support methods used in the United States. Characteristics of bad roof and associated roof failure theories are briefly presented as background to roof support. Methods of detecting and monitoring roof behavior and/or bolt performance provide essential feedback on roof support requirements. A discussion follows on roof bolt design that assimilates roof and support parameters into useful equations or nomographs to help decide what bolt types to use and how they should be installed under different roof conditions. 35 refs., 8 figs.

  14. EMA-qPCR to monitor the efficiency of a closed-coupled solar pasteurization system in reducing Legionella contamination of roof-harvested rainwater.

    PubMed

    Reyneke, B; Dobrowsky, P H; Ndlovu, T; Khan, S; Khan, W

    2016-05-15

    Solar pasteurization is effective in reducing the level of indicator organisms in stored rainwater to within drinking water standards. However, Legionella spp. were detected at temperatures exceeding the recommended pasteurization temperatures using polymerase chain reaction assays. The aim of the current study was thus to apply EMA quantitative polymerase chain reaction (EMA-qPCR) to determine whether the Legionella spp. detected were intact cells and therefore possibly viable at pasteurization temperatures >70°C. The BacTiter-Glo™ Microbial Cell Viability Assay was also used to detect the presence of ATP in the tested samples, as ATP indicates the presence of metabolically active cells. Chemical analysis also indicated that all anions and cations were within the respective drinking water guidelines, with the exception of iron (mean: 186.76μg/L) and aluminium (mean: 188.13μg/L), which were detected in the pasteurized tank water samples at levels exceeding recommended guidelines. The BacTiter-Glo™ Microbial Cell Viability Assay indicated the presence of viable cells for all pasteurized temperatures tested, with the percentage of ATP (in the form of relative light units) decreasing with increasing temperature [70-79°C (96.7%); 80- 89°C (99.2%); 90-95°C (99.7%)]. EMA-qPCR then indicated that while solar pasteurization significantly reduced (p<0.05) the genomic copy numbers of intact Legionella cells in the pasteurized tank water (~99%), no significant difference (p>0.05) in the mean copy numbers was detected with an increase in the pasteurization temperature, with 6×10(3) genomic copies/mL DNA sample obtained at 95°C. As intact Legionella cells were detected in the pasteurized tank water samples, quantitative microbial risk assessment studies need to be conducted to determine the potential health risk associated with using the water for domestic purposes. PMID:26990076

  15. Integration of solar sail and thin film solar cell using spectrum splitting technology for deep space exploration

    NASA Astrophysics Data System (ADS)

    Feng, Yudong; Zuo, Huaping; Wang, Zhimin

    It is very important to lighten weight for deep space exploration. Thin film type spacecrafts like solar sails may be the good choice. Due to the favourable photoelectric effect in weak light and light weight, flexible thin film solar sell will also be considered as new generation energy. In order to integrate thin film solar cell into solar sail perfectly, the spectrum splitting technology using optical multilayer film is employed to divide the solar spectrum. The transmissivity of the designed optical film is calculated by a developed computer program. It shows that that the transmissivity is larger than 95% in the range 400-1000nm, and obviously decrease above 400 nm, and below 1000 nm. The result given in this work will provide a new way to realize a low area mass of the solar sail.

  16. 30 CFR 75.204 - Roof bolting.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... accessories addressed in ASTM F432-95, “Standard Specification for Roof and Rock Bolts and Accessories,” the.... (4) In each roof bolting cycle, the actual torque or tension of the first tensioned roof bolt... during each roof bolting cycle shall be tested during or immediately after the first row of bolts...

  17. 30 CFR 75.204 - Roof bolting.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... accessories addressed in ASTM F432-95, “Standard Specification for Roof and Rock Bolts and Accessories,” the.... (4) In each roof bolting cycle, the actual torque or tension of the first tensioned roof bolt... during each roof bolting cycle shall be tested during or immediately after the first row of bolts...

  18. 30 CFR 75.204 - Roof bolting.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... accessories addressed in ASTM F432-95, “Standard Specification for Roof and Rock Bolts and Accessories,” the.... (4) In each roof bolting cycle, the actual torque or tension of the first tensioned roof bolt... during each roof bolting cycle shall be tested during or immediately after the first row of bolts...

  19. Sustainable roofs with real energy savings

    SciTech Connect

    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.

  20. Green Roofs for Stormwater Runoff Control

    EPA Science Inventory

    This project evaluated green roofs as a stormwater management tool. Specifically, runoff quantity and quality from green and flat asphalt roofs were compared. Evapotranspiration from planted green roofs and evaporation from unplanted media roofs were also compared. The influence...

  1. Radiation control coatings installed on rough-surfaced built-up roofs -- Initial results

    SciTech Connect

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

    1998-01-01

    The authors have tracked the solar reflectance and thermal performance of small samples of various radiation control coatings on smooth surfaces for several years on a roof test facility in East Tennessee. The focus is on white coatings because of their potential to weather, causing the solar reflectance to decrease as the coatings age. Support of the federal New Technology Demonstration Program allowed them to extend the study to more samples on smooth surfaces and entire rough-surfaced roofs at a federal facility in the Panhandle of Florida. Two rough-surfaced, moderately well-insulated, low solar reflectance built-up roofs (BURs) were spray-coated with a latex-based product with ceramic beads added to improve solar reflectance. In the first three months after installation, the fresh BUR coatings showed a significant decrease in both the outside-surface temperature and the heat flux through the roof insulation. Average sunlit values were generated to exclude nighttime data, data on cloudy days, and data when the uncoated patch on one roof was more strongly shaded in mid-afternoon on sunny days. The average power demand during occupied periods for the first month with the coating for the building with the thermally massive roof deck was 13% less than during the previous month without the coating. For the other buildings with a lightweight roof deck but high internal loads, there were no clear average power savings due to the coating. The authors are continuing to monitor electricity use in these all-electric buildings to calibrate a model for the peak power and annual energy use of the buildings. Modeling results to be given at the end of the two year project will address the effect of roof R-value, geographic location, and solar reflectance, including the effect of weathering, on the performance of coated roofs. The calibrated models should allow one to segregate site-specific effects such as shading and large thermal mass.

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

    SciTech Connect

    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, Pa rt 6 of the California Code of Regulations) for nonresidential buildings with low-sloped roofs include a cool-roof prescriptive requirement in all California climate zones. Buildings with roofs that do not meet prescriptive requirements may comply with the code via an ''overall-envelope'' approach (non-metal roofs only), or via a performance approach (all roof types).

  3. Using Remote Sensing to Quantify Roof Albedo in Seven California Cities

    NASA Astrophysics Data System (ADS)

    Ban-Weiss, G. A.; Woods, J.; Millstein, D.; Levinson, R.

    2013-12-01

    Cool roofs reflect sunlight and therefore can reduce cooling energy use in buildings. Further, since roofs cover about 20-25% of cities, wide spread deployment of cool roofs could mitigate the urban heat island effect and partially counter urban temperature increases associated with global climate change. Accurately predicting the potential for increasing urban albedo using reflective roofs and its associated energy use and climate benefits requires detailed knowledge of the current stock of roofs at the city scale. Until now this knowledge has been limited due to a lack of availability of albedo data with sufficient spatial coverage, spatial resolution, and spectral information. In this work we use a novel source of multiband aerial imagery to derive the albedos of individual roofs in seven California cities: Los Angeles, Long Beach, San Diego, Bakersfield, Sacramento, San Francisco, and San Jose. The radiometrically calibrated, remotely sensed imagery has high spatial resolution (1 m) and four narrow (less than 0.1 μm wide) band reflectances: blue, green, red, and near-infrared. To derive the albedo of roofs in each city, we first locate roof pixels within GIS building outlines. Next we use laboratory measurements of the solar spectral reflectances of 190 roofing products to empirically relate solar reflectance (albedo) to reflectances in the four narrow bands; the root-mean-square of the residuals for the albedo prediction is 0.016. Albedos computed from remotely sensed reflectances are calibrated to ground measurements of roof albedo in each city. The error (both precision and accuracy) of albedo values is presented for each city. The area-weighted mean roof albedo (× standard deviation) for each city ranges from 0.17 × 0.08 (Los Angeles) to 0.29 × 0.15 (San Diego). In each city most roofs have low albedo in the range of 0.1 to 0.3. Roofs with albedo greater than 0.4 comprise less than 3% of total roofs and 7% of total roof area in each city. The California Building Energy Efficiency Standard (Title-24, Part 6) includes the use of high-albedo surfaces on low-sloped roofs on non-residential buildings. Analyzing a subset of large presumably commercial buildings, we find high albedo roofs represent 0.5% and 10% of total roofs and roof surface area, respectively. The potential for high albedo roofs to reduce urban temperatures was investigated for a California city (Bakersfield) with warm summers using a state-of-the-art meteorological model (Weather Research and Forecasting, WRF). Base case and cool roof scenarios were simulated with the only difference being that the surface albedo was increased under the cool roof scenario. Roof albedos derived from the aerial imagery were used as an input to the climate model in the base case scenario. Simulation results indicate that seasonal average afternoon (1500 h) temperatures could be reduced by up to 0.2 °C across Bakersfield during both the summer and winter. While temperature changes are similar during winter and summer, only summer shows statistically significant temperature changes downwind (southeast) from Bakersfield. This indicates that reduced summertime temperatures may be felt over a distance that is 2 or 3 times the length scale of the region with high albedo roofs.

  4. The design, effectiveness and construction of passive-thermal-control roofing shingles

    NASA Astrophysics Data System (ADS)

    Wolf, L., Jr.

    1982-09-01

    The concept of a passive thermal control roofing shingle, which is a shingle that reflects the summer sun and absorbs the winter sun, is discussed. It is indicated that it is possible to design shingles for particular latitudes and styles of roof which absorb nearly all of the winter solar energy and reflect nearly all of the summer solar energy. Calculations of the energy savings and cost effectiveness of the passive thermal control roofing shingle indicate that it is most cost effective on all south facing pitched roofs regardless of heating fuel type, and on flat or east or west facing roofs that are heated with costly fuels such as electricity or heating oil. The shingle is most effective on poorly insulated structures. The feasibility of using the passive thermal control roofing shingle in conjunction with a heat pump to pump heat absorbed by the shingle into a well insulated structure is demonstrated. Construction of a variety of models of the passive thermal control roofing shingle illustrate numerous alternate methods of manufacture. A profile extruded, plastic, glazed shingle appears to be the most promising approach. Use of a glazed shingle can increase the effectiveness of the passive thermal control roofing shingle by reducing convective heat losses.

  5. a Research on the Hierarchy and Completeness of Roof Topology for Robust Building Reconstruction from Airborne Point Cloud

    NASA Astrophysics Data System (ADS)

    Xu, B.; Jiang, W. S.; Zhu, Q. S.

    2015-05-01

    In this work, we concentrate on the hierarchy and completeness of roof topology, and the aim is to avoid or correct the errors in roof topology. The hierarchy of topology is expressed by the hierarchical roof topology graph (HRTG) in accord with the definition of CityGML LOD (level of details). We decompose the roof topology graph (RTG) with a progressive approach while maintain the integrality and consistency of the data set simultaneously. Common feathers like collinear ridges or boundaries are calculated integrally to maintain their completeness. The roof items will only detected locally to decrease the error caused by data spare or mutual interference. Finally, a topology completeness test is adopted to detect and correct errors in roof topology, which results in a complete and hierarchical building model. Experiments shows that our methods have obvious improvements to the RTG based reconstruction method, especially for sparse data or roof topology with ambiguous.

  6. Low Impact Development (LID) Technologies for Sustainable Water Management: Studies from a Green Roof

    NASA Astrophysics Data System (ADS)

    Digiovanni, K. A.; Montalto, F. A.; Gaffin, S.

    2009-12-01

    Anthropogenic induced landscape alterations, such as urbanization, can cause drastic alterations to predevelopment hydrologic conditions and the systems linked to these cycles. Low impact development (LID) technologies, such as green roofs, can help to minimize these impacts given their ability to retain and detain stormwater and subsequently evapotranspire or infiltrate excess water. An innovative technique for simultaneously monitoring stormwater retention, allowing for runoff quantification, as well as evapotranspiration from a small scale green roof box was employed for a green roof at the Ethical Culture Fieldston School located in the Bronx, NY. A 1.2 meter long by 0.6 meter wide green roof box was created as a replica section of the 525 m2 green roof on the building. The layers of the green roof box consisted of a roof membrane, drainage layer, four inch media layer, and vegetative Sedum layer. Monitoring equipment on the green roof included a weather station and real time environmental sensors which quantify wind speed, precipitation, soil moisture, temperature, humidity, albedo, and incident solar radiation. In addition to this equipment, a platform scale was positioned beneath the green roof box. Data was collected at 5 minute time intervals over a six month monitoring period between Spring and Fall 2009. A mass balance technique was utilized to quantify runoff from the green roof box. Evapotranspiration during antecedent conditions was also quantified utilizing a mass balance methodology and compared to energy balance estimates based on climatic conditions measured on the green roof. Results of runoff generation under a variety of rainfall conditions, as well as a comparison between mass balance and energy balance measures of evapotranspiration will be presented. The incorporation of this and further data collection into model development and calibration activities will be informative in predicting the impact that the implementation of green roof technologies could have on hydrologic patterns in urban areas and the subsequent impact on systems linked to these hydrologic cycles.

  7. On-chip energy storage integrated with solar cells using a laser scribed graphene oxide film

    NASA Astrophysics Data System (ADS)

    Thekkekara, Litty V.; Jia, Baohua; Zhang, Yinan; Qiu, Ling; Li, Dan; Gu, Min

    2015-07-01

    We demonstrate an on-chip concept of the energy storage integrated with crystalline silicon solar cells using a laser scribed graphene oxide film, which can lead to the miniaturization in size and the minimization in cost of optoelectronic devices. The integrated solar supercapacitor with 62% columbic efficiency is directly written on the reverse side of solar cell without any loss in the solar cell performance. The energy and power density of the obtained energy storage devices are comparable to those of electrolytic capacitors even after a number of charging-discharging measurements.

  8. [A review of green roof performance towards management of roof runoff].

    PubMed

    Chen, Xiao-ping; Huang, Pei; Zhou, Zhi-xiang; Gao, Chi

    2015-08-01

    Green roof has a significant influence on reducing runoff volume, delaying runoff-yielding time, reducing the peak flow and improving runoff quality. This paper addressed the related research around the world and concluded from several aspects, i.e., the definition of green roof of different types, the mechanism how green roof manages runoff quantity and quality, the ability how green roof controls roof runoff, and the influence factors of green roof toward runoff quantity and quality. Afterwards, there was a need for more future work on research of green roof toward roof runoff, i.e., vegetation selection of green roof, efficient construction model selection of green roof, the regulating characteristics of green roof on roof runoff, the value assessment of green roof on roof runoff, analysis of source-sink function of green roof on the water pollutants of roof runoff and the research on the mitigation measures of roof runoff pollution. This paper provided a guideline to develop green roofs aiming to regulating roof runoff. PMID:26685624

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

    SciTech Connect

    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.

  10. Reuniting the Solar System: Integrated Education and Public Outreach Projects for Solar System Exploration Missions and Programs

    NASA Technical Reports Server (NTRS)

    Lowes, Leslie; Lindstrom, Marilyn; Stockman, Stephanie; Scalice, Daniela; Klug, Sheri

    2003-01-01

    The Solar System Exploration Education Forum has worked for five years to foster Education and Public Outreach (E/PO) cooperation among missions and programs in order to leverage resources and better meet the needs of educators and the public. These efforts are coming together in a number of programs and products and in '2004 - The Year of the Solar System.' NASA's practice of having independent E/PO programs for each mission and its public affairs emphasis on uniqueness has led to a public perception of a fragmented solar system exploration program. By working to integrate solar system E/PO, the breadth and depth of the solar system exploration program is revealed. When emphasis is put on what missions have in common, as well as their differences, each mission is seen in the context of the whole program.

  11. Photovoltaic Roof Heat Flux

    NASA Astrophysics Data System (ADS)

    Samady, Mezhgan Frishta

    Solar panels were mounted with different designs onto 1:800 scale building models while temperature and radiation were measured. While there have been other studies aimed at finding the optimal angles for solar panels [9], in this study both the angle and the mounting method were tested. The three PV mounting designs that were considered to provide the most insulation to a building's rooftop were flush, offset (control), and angled. The solar panel offset height became a key component for rooftop insulation as well as the performance of the actual solar panel. Experimental results were given to verify the thermal behavior of the heat loads from the different designs of the photovoltaic panel. From the results, the angled PV design needed 16Z more heat extraction than the offset and flush PV design needed 60% more heat extracted than the offset. In addition to the heat transfer analysis, thermal models were performed to incorporate main atmospheric conditions which were based on the effects of PV mounting structure.

  12. Design Considerations for an Integrated Solar Sail Diagnostics System

    NASA Technical Reports Server (NTRS)

    Jenkins, Christopher H. M.; Gough, Aaron R.; Pappa, Richard S.; Carroll, Joe; Blandino, Joseph R.; Miles, Jonathan J.; Rakoczy, John

    2004-01-01

    Efforts are continuing under NASA support to improve the readiness level of solar sail technology. Solar sails have one of the best chances to be the next gossamer spacecraft flown in space. In the gossamer spacecraft community thus far, solar sails have always been considered a "low precision" application compared with, say, radar or optical devices. However, as this paper shows, even low precision gossamer applications put extraordinary demands on structural measurement systems if they are to be traceable to use in space.

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

    SciTech Connect

    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.

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

    SciTech Connect

    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.

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

    SciTech Connect

    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.

  16. NASA's Integrated Development of Solar Sail Propulsion Project

    NASA Technical Reports Server (NTRS)

    Garbe, Gregory; Montgomery, Edward E., IV; Heaton, Andrew F.; VanSant, John T.; Campbell, Bruce A.

    2004-01-01

    Solar sails have been studied for a variety of missions and have the potential to provide cost effective, propellantless propulsion that enables longer on-station operation, increased scientific payload mass fraction, and access to previously inaccessible orbits (e. g., non-Keplerian, high solar latitudes, etc.). Research being conducted by the In-Space Propulsion (ISP) Technologies Projects is at the forefront of NASA's efforts to mature propulsion technologies that will enable or enhance a variety of space science missions. Solar sail propulsion systems will be required to meet the challenge of monitoring and predicting space weather by the Office of Space Science's (OSS) Living with a Star (LWS) program. Near-to-mid-term mission needs include monitoring of solar activity and observations at high solar latitudes. Work currently funded by the ISP s Solar Sail Propulsion (SSP) project is based on the quantitative demonstration of scalability of present solar sail subsystem designs and concepts to future mission requirements through ground testing of hardware, computational modeling and analytical simulations. This paper will give an overview of the Solar Sail Propulsion project's major development tasks of fabricating and testing two different subscale (400 square meter sail) solar sail system architectures. It will then be shown how either of these subscale prototypes can evolve into a flight validation system and briefly discuss the mission parameter. The paper will conclude with a discussion on how a flight validation will exercise the quantitative tools needed to demonstrate the scale to the size needed for the Solar Polar Imager and L1-Diamond SEC roadmap missions.

  17. A Solar Cell Powered Adaptive Charging Circuit for CMOS Integrated Micro Fuel Cells

    NASA Astrophysics Data System (ADS)

    Moranz, C.; Ghafarian M, H.; Ylli, K.; Manoli, Y.

    2015-12-01

    This paper presents an autonomous interface circuit which uses solar cells to automatically recharge chip integrated micro fuel cell accumulator arrays. These accumulators comprise a fuel cell for powering systems and a hydrolysis cell for charging the integrated hydrogen storage. The charging current is continuously monitored and the interface circuit automatically maximizes and controls the charging current. The solar cells powering the charging process are projected to be part of the chip package. The presented system, in combination with a previously developed voltage regulator and integrated sensors or actuators enables the implementation of fully integrated energy autonomous systems.

  18. D Local Scale Solar Radiation Model Based on Urban LIDAR Data

    NASA Astrophysics Data System (ADS)

    Redweik, P. M.; Catita, C.; Brito, M. C.

    2011-09-01

    The aim of the present study is to obtain the direct, diffuse and reflected solar energy that reaches a generic point of an urban landscape regardless of its location on a roof, on the ground or on a façade. The vertical façades embody a discontinuity in a digital elevation surface function and most models fail in the determination of solar radiation for points on façades. The presented algorithm solves the problem in an integrated way: starting with a georreferenced LIDAR data cloud covering a 400 × 400 m2 urban area resampled in a 1m × 1m mesh, applies a new shadow algorithm over roofs, terrain and façades for each time frame, applies the Kumar solar radiation model for the calculation of direct, diffuse and reflected irradiation for each 1x1m raster cell on non vertical surfaces of roof and terrain, and calculates total and mean irradiation of each 1 meter wide column of vertical façade based on the illuminated area at each time frame. The results for each time frame are integrated for the wished time period from one hour to one year, being the time steps also selectable, allowing several kinds of solar radiation and shadowing studies. GIS were used to evaluate monthly averages of solar radiation for a particular location as well as to map the photovoltaic potential of the building façades and their roofs according to determined classes of potential.

  19. Integrated Antenna/Solar Array Cell (IA/SAC) System for Flexible Access Communications

    NASA Technical Reports Server (NTRS)

    Lee, Ricard Q.; Clark, Eric B.; Pal, Anna Maria T.; Wilt, David M.; Mueller, Carl H.

    2004-01-01

    Present satellite communications systems normally use separate solar cells and antennas. Since solar cells generally account for the largest surface area of the spacecraft, co-locating the antenna and solar cells on the same substrate opens the possibility for a number of data-rate-enhancing communications link architecture that would have minimal impact on spacecraft weight and size. The idea of integrating printed planar antenna and solar array cells on the same surface has been reported in the literature. The early work merely attempted to demonstrate the feasibility by placing commercial solar cells besides a patch antenna. Recently, Integrating multiple antenna elements and solar cell arrays on the same surface was reported for both space and terrestrial applications. The application of photovoltaic solar cell in a planar antenna structure where the radiating patch antenna is replaced by a Si solar cell has been demonstrated in wireless communication systems (C. Bendel, J. Kirchhof and N. Henze, 3rd Would Photovotaic Congress, Osaka, Japan, May 2003). Based on a hybrid approach, a 6x1 slot array with circularly polarized crossdipole elements co-located on the same surface of the solar cells array has been demonstrated (S. Vaccaro, J. R. Mosig and P. de Maagt, IEEE Trans. Ant. and Propag., Vol. 5 1, No. 8, Aug. 2003). Amorphous silicon solar cells with about 5-10% efficiency were used in these demonstrations. This paper describes recent effort to integrate advanced solar cells with printed planar antennas. Compared to prior art, the proposed WSAC concept is unique in the following ways: 1) Active antenna element will be used to achieve dynamic beam steering; 2) High efficiency (30%) GaAs multi-junction solar cells will be used instead of Si, which has an efficiency of about 15%; 3) Antenna and solar cells are integrated on a common GaAs substrate; and 4) Higher data rate capability. The IA/SAC is designed to operate at X-band (8-12 GH) and higher frequencies Higher operating frequencies enable greater bandwidth and thus higher data transfer rates. The first phase of the effort involves the development of GaAs solar cell MIMs (Monolithically Integrated Module) with a single patch antenna on the opposite side of the substrate. Subsequent work will involve the integration of MIMs and antennas on the same side of the substrate. Results from the phase one efforts will be presented.

  20. OUT Success Stories: Solar Roofing Shingles

    DOE R&D Accomplishments Database

    Johnson, N.

    2000-08-01

    Thin-film photovoltaic (PV) cells are now doubling as rooftop shingles. PV shingles offer many advantages. The energy generated from a building's PV rooftop shingles can provide power both to the building and the utility's power grid.

  1. Roofing Workbook and Tests: Entering the Roofing and Waterproofing Industry.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento. Vocational Education Services.

    This document is one of a series of nine individual units of instruction for use in roofing apprenticeship classes in California. The unit consists of a workbook and test, perforated for student use. Fourteen topics are covered in the workbook and corresponding multiple-choice tests. For each topic, objectives, information sheets, and study…

  2. The green roof dilemma - discussion of Francis and Lorimer (2011).

    PubMed

    Henry, Alexandre; Frascaria-Lacoste, Nathalie

    2012-08-15

    Urban ecosystems are the most complex mosaics of vegetative land cover that can be found. In a recent paper, Francis and Lorimer (2011) evaluated the reconciliation potential of living roofs and walls. For these authors, these two techniques for habitat improvement have strong potential for urban reconciliation ecology. However they have some ecological and societal limitations such as the physical extreme environmental characteristics, the monetary investment and the cultural perceptions of urban nature. We are interested in their results and support their conclusions. However, for a considerable time, green roofs have been designed to provide urban greenery for buildings and the green roof market has only focused on extensive roof at a restricted scale within cities. Thus, we have strong doubts about the relevance of their use as possible integrated elements of the network. Furthermore, without dynamic progress in research and the implementation of well-thought-out policies, what will be the real capital gain from green roofs with respect to land-use complementation in cities? If we agree with Francis and Lorimer (2011) considering that urban reconciliation ecology between nature and citizens is a current major challenge, then "adaptive collaborative management" is a fundamental requirement. PMID:22484659

  3. Solar panel installation configurations for optimum system performance

    NASA Astrophysics Data System (ADS)

    Jha, A. R.

    2010-08-01

    The main object of this paper is to identify solar panel installation configurations to achieve optimum system performance irrespective of installation surface configurations. It is important to mention that the panel installation requirements are strictly dependent on the roof configurations, Northern and Southern hemispherical locations, and the latitudes of the installation locations. Panel installation schemes for flat roof, inclined roof, inverted V-shape roof and other roof configurations are briefly discussed. Potential tracking concepts, tracking algorithms, and controllers are identified.

  4. IDENTIFYING ROOF FALL PREDICTORS USING FUZZY CLASSIFICATION

    SciTech Connect

    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.

  5. Identifying Roof Fall Predictors Using Fuzzy Classification

    NASA Astrophysics Data System (ADS)

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

    2010-02-01

    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.

  6. Roof bolting without injury. [Glossary included

    SciTech Connect

    Larry, J.J.

    1992-01-01

    The art of roof bolting is an important segment of the mining cycle in underground coal mining. Too many accidents occur that can be attributed to the roof bolting process. Too often the Roof Bolter Operator is not cognizant of the art, or drilling techniques, nor the safety procedures to perform the duties effectively and safely. This manual offers those safety pointers and drilling techniques for the Roof Bolter Operator and the Roof Bolter Helper. The manual will instruct the Operators on the operational functions and the lubrication of the Bolter, the concept of roof bolting and emphasize the safety-oriented steps for roof-bolting safely. Conversely the manual will point out the hazards of poor safety habits that lead to accidents and injuries. If the Roof Bolter crew heed the recommendations described herein, they will provide a safe working environment for all of the employees at the mine. Chapters have been process separately for inclusion on the data base.

  7. Integrating Multiple Approaches to Solving Solar Wind Turbulence Problems (Invited)

    NASA Astrophysics Data System (ADS)

    Karimabadi, H.; Roytershteyn, V.

    2013-12-01

    The ultimate understanding of the solar wind turbulence must explain the physical process and their connection at all scales ranging from the largest down to electron kinetic scales. This is a daunting task and as a result a more piecemeal approach to the problem has been followed. For example, the role of each wave has been explored in isolation and in simulations with scales limited to those of the underlying waves. In this talk, we present several issues with this approach and offer an alternative with an eye towards more realistic simulations of solar wind turbulence. The main simulation techniques used have been MHD, Hall MHD, hybrid, fully kinetic, and gyrokinetic. We examine the limitations of each approach and their viability for studies of solar wind turbulence. Finally, the effect of initial conditions on the resulting turbulence and their comparison with solar wind are demonstrated through several kinetic simulations.

  8. The Western Wind and Solar Integration Study Phase 2 (Executive Summary)

    SciTech Connect

    Lew, Debra; Brinkman, Greg

    2013-09-01

    The electric grid is a highly complex, interconnected machine, and changing one part of the grid can have consequences elsewhere. Adding wind and solar affects the operation of the other power plants and adding high penetrations can induce cycling of fossil-fueled generators. Cycling leads to wear-and-tear costs and changes in emissions. Phase 2 of the Western Wind and Solar Integration Study (WWSIS-2) evaluated these costs and emissions and simulated grid operations for a year to investigate the detailed impact of wind and solar on the fossil-fueled fleet. This built on Phase 1, one of the largest wind and solar integration studies ever conducted, which examined operational impacts of high wind and solar penetrations in the West(GE Energy 2010).

  9. 40 CFR 65.43 - Fixed roof with an internal floating roof (IFR).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Storage Vessels § 65.43 Fixed roof with an... storage vessel regulated material emissions by using a fixed roof and an internal floating roof shall... floating roof shall be equipped with a closure device between the wall of the storage vessel and...

  10. 40 CFR 65.43 - Fixed roof with an internal floating roof (IFR).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Storage Vessels § 65.43 Fixed roof with an... storage vessel regulated material emissions by using a fixed roof and an internal floating roof shall... floating roof shall be equipped with a closure device between the wall of the storage vessel and...

  11. Roofing: Workbook and Tests. Common Roofing and Waterproofing Materials and Equipment.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento. Bureau of Publications.

    This workbook on materials and equipment is one of a series of nine individual units of instruction for roofing apprenticeship classes in California. The workbook covers eight topics: production of bitumens and asphaltic roofing materials; built-up roofing materials and adhesives; asphaltic products and rigid roofing materials; elastomeric and…

  12. Common Roofing and Waterproofing Materials and Equipment. Roofing Workbook and Tests.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento. Bureau of Publications.

    This publication on common roofing and waterproofing materials and equipment is one of a series of units of instruction for roofing apprenticeship classes. The workbook portion is divided into eight topics: production of bitumens and asphalt roofing materials, built-up materials and adhesives, asphalt products and rigid roofing materials,…

  13. Cold-Applied Roofing Systems and Waterproofing and Dampproofing. Roofing Workbook and Tests.

    ERIC Educational Resources Information Center

    Brown, Arthur

    This workbook for students in California roofing apprenticeship programs provides information for classroom work in the area of cold-applied roofing systems and waterproofing and dampproofing. Eight topics are covered: introduction to cold-applied roofing systems and waterproofing and dampproofing, tools and equipment used in cold-applied roofing,…

  14. Integrating Wind and Solar Energy in the U.S. Bulk Power System: Lessons from Regional Integration Studies

    SciTech Connect

    Bird, L.; Lew, D.

    2012-09-01

    Two recent studies sponsored by the U.S. Department of Energy (DOE) and the National Renewable Energy Laboratory (NREL) have examined the impacts of integrating high penetrations of wind and solar energy on the Eastern and Western electric grids. The Eastern Wind Integration and Transmission Study (EWITS), initiated in 2007, examined the impact on power system operations of reaching 20% to 30% wind energy penetration in the Eastern Interconnection. The Western Wind and Solar Integration Study (WWSIS) examined the operational implications of adding up to 35% wind and solar energy penetration to the Western Interconnect. Both studies examined the costs of integrating variable renewable energy generation into the grid and transmission and operational changes that might be necessary to address higher penetrations of wind or solar generation. This paper identifies key insights from these regional studies for integrating high penetrations of renewables in the U.S. electric grid. The studies share a number of key findings, although in some instances the results vary due to differences in grid operations and markets, the geographic location of the renewables, and the need for transmission.

  15. 30 CFR 75.204 - Roof bolting.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Roof bolting. 75.204 Section 75.204 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.204 Roof bolting. (a) For roof bolts and accessories addressed in ASTM F432-95,...

  16. 30 CFR 75.204 - Roof bolting.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Roof bolting. 75.204 Section 75.204 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.204 Roof bolting. (a) For roof bolts and accessories addressed in ASTM F432-95,...

  17. 7 CFR 2902.11 - Roof coatings.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... CFR 247.12. ... 7 Agriculture 15 2010-01-01 2010-01-01 false Roof coatings. 2902.11 Section 2902.11 Agriculture... Roof coatings. (a) Definition. Coatings formulated for use in commercial roof deck systems to provide...

  18. Guidelines for Inspecting Your Roof Systems.

    ERIC Educational Resources Information Center

    Watkins, Daniel L.

    2003-01-01

    Provides guidelines for inspecting the roof of a facility. Suggests that periodic roof inspections should be performed on a quarterly or semi-annual basis and after severe storms. Proactively identifying potential problem areas is the best defense against roof leaks. (SLD)

  19. GREEN ROOFS — A GROWING TREND

    EPA Science Inventory

    One of the most interesting stormwater control systems under evaluation by EPA are “green roofs”. Green roofs are vegetative covers applied to building roofs to slow, or totally absorb, rainfall runoff during storms. While the concept of over-planted roofs is very ancient, the go...

  20. 7 CFR 3201.11 - Roof coatings.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Guideline, 40 CFR 247.12. ... 7 Agriculture 15 2012-01-01 2012-01-01 false Roof coatings. 3201.11 Section 3201.11 Agriculture... Items § 3201.11 Roof coatings. (a) Definition. Coatings formulated for use in commercial roof...

  1. 7 CFR 3201.11 - Roof coatings.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Guideline, 40 CFR 247.12. ... 7 Agriculture 15 2014-01-01 2014-01-01 false Roof coatings. 3201.11 Section 3201.11 Agriculture... Items § 3201.11 Roof coatings. (a) Definition. Coatings formulated for use in commercial roof...

  2. 7 CFR 3201.11 - Roof coatings.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Guideline, 40 CFR 247.12. ... 7 Agriculture 15 2013-01-01 2013-01-01 false Roof coatings. 3201.11 Section 3201.11 Agriculture... Items § 3201.11 Roof coatings. (a) Definition. Coatings formulated for use in commercial roof...

  3. 7 CFR 2902.11 - Roof coatings.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... CFR 247.12. ... 7 Agriculture 15 2011-01-01 2011-01-01 false Roof coatings. 2902.11 Section 2902.11 Agriculture... Roof coatings. (a) Definition. Coatings formulated for use in commercial roof deck systems to provide...

  4. Roofing Materials Assessment: Investigation of Five Metals in Runoff from Roofing Materials.

    PubMed

    Winters, Nancy; Granuke, Kyle; McCall, Melissa

    2015-09-01

    To assess the contribution of five toxic metals from new roofing materials to stormwater, runoff was collected from 14 types of roofing materials and controls during 20 rain events and analyzed for metals. Many of the new roofing materials evaluated did not show elevated metals concentrations in the runoff. Runoff from several other roofing materials was significantly higher than the controls for arsenic, copper, and zinc. Notably, treated wood shakes released arsenic and copper, copper roofing released copper, PVC roofing released arsenic, and Zincalume® and EPDM roofing released zinc. For the runoff from some of the roofing materials, metals concentrations decreased significantly over an approximately one-year period of aging. Metals concentrations in runoff were demonstrated to depend on a number of factors, such as roofing materials, age of the materials, and climatic conditions. Thus, application of runoff concentrations from roofing materials to estimate basin-wide releases should be undertaken cautiously. PMID:26961477

  5. Roof heat loss detection using airborne thermal infrared imagery

    NASA Astrophysics Data System (ADS)

    Kern, K.; Bauer, C.; Sulzer, W.

    2012-12-01

    As part of the Austrian and European attempt to reduce energy consumption and greenhouse gas emissions, thermal rehabilitation and the improvement of the energy efficiency of buildings became an important topic in research as well as in building construction and refurbishment. Today, in-situ thermal infrared measurements are routinely used to determine energy loss through the building envelope. However, in-situ thermal surveys are expensive and time consuming, and in many cases the detection of the amount and location of waste heat leaving building through roofs is not possible with ground-based observations. For some years now, a new generation of high-resolution thermal infrared sensors makes it possible to survey heat-loss through roofs at a high level of detail and accuracy. However, to date, comparable studies have mainly been conducted on buildings with uniform roof covering and provided two-dimensional, qualitative information. This pilot study aims to survey the heat-loss through roofs of the buildings of the University of Graz (Austria) campus by using high-resolution airborne thermal infrared imagery (TABI 1800 - Thermal Airborne Broadband imager). TABI-1800 acquires data in a spectral range from 3.7 - 4.8 micron, a thermal resolution of 0.05 °C and a spatial resolution of 0.6 m. The remote sensing data is calibrated to different roof coverings (e.g. clay shingle, asphalt shingle, tin roof, glass) and combined with a roof surface model to determine the amount of waste heat leaving the building and to identify hot spots. The additional integration of information about the conditions underneath the roofs into the study allows a more detailed analysis of the upward heat flux and is a significant improvement of existing methods. The resulting data set provides useful information to the university facility service for infrastructure maintenance, especially in terms of attic and roof insulation improvements. Beyond that, the project is supposed to raise public awareness in the context of climate-neutral actions, and in a long run, contribute to significantly reduce energy consumption and GHG emissions.

  6. Radiation control coatings on rough-surfaced roofs at a federal facility: Two summers of monitoring plus roof and whole building modeling

    SciTech Connect

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

    1998-01-01

    Support of the federal New Technology Demonstration Program (NTDP) allowed the authors to learn the effect of radiation control coatings on roofs at a federal facility in the Panhandle of Florida. Two rough-surfaced, moderately well-insulated, low solar reflectance built-up roofs (BURs) were spray coated with a white, latex-based product with ceramic beads. Samples of the coated roofs were brought periodically to the laboratory to measure the solar reflectance as the coatings weathered. The authors monitored the power demand of the all-electric buildings that the roofs covered and temperatures and heat fluxes for two instrumented areas on each roof. Average decreases in the sunlit temperatures of the coated vs. the uncoated surfaces show weathering effects. They also show that the shading enhanced the effect of the coating on the significantly shaded roof because the coated instrumented area on it was preferentially shaded near noon of sunny days. Whole building models were constructed for DOE 2.1E and model predictions were compared to measurements of total electrical power for each all-electric building. The building with the significantly shaded roof had very high internal loads. The effect of the shading on annual energy use for cooling was twice that of the coating but the coating decreased annual cooling energy needs only by 0.5%. The building with the heavyweight concrete-decked roof had small internal loads. For it, the DOE 2.1E model predicted a 7.4% decrease in annual cooling energy use due to the coating and a comparatively small effect of the less extensive shading.

  7. Integrated residential photovoltaic array development

    NASA Technical Reports Server (NTRS)

    Shepard, N. F., Jr.

    1981-01-01

    The design details of an optimized integrated residential photovoltaic module/array are presented. This selected design features a waterproofing and mounting scheme which was devised to simplify the installation procedures by the avoidance of complex gasketed or caulked joints, while still maintaining a high confidence that the watertight integrity of the integral roofing surface will be achieved for the design lifetime of the system. The production and installation costs for the selected module/array design are reported for a range of annual production rates as a function of the cost of solar cells.

  8. Solar Energy Demonstrations

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Solar energy furnishes all of the heating and hot water needs, plus 80 percent of the air conditioning, for the two-story Reedy Creek building. A unique feature of this installation is that the 16 semi-cylindrical solar collectors (center photo on opposite page with closeup of a single collector below it) are not mounted atop the roof as is customary, they actually are the roof. This arrangement eliminates the usual trusses, corrugated decking and insulating concrete in roof construction; that, in turn, reduces overall building costs and makes the solar installation more attractive economically. The Reedy Creek collectors were designed and manufactured by AAI Corporation of Baltimore, Maryland.

  9. A Roof for ALMA

    NASA Astrophysics Data System (ADS)

    2007-03-01

    On 10 March, an official ceremony took place on the 2,900m high site of the Atacama Large Millimeter/submillimeter Array (ALMA) Operations Support Facility, from where the ALMA antennas will be remotely controlled. The ceremony marked the completion of the structural works, while the building itself will be finished by the end of the year. This will become the operational centre of one of the most important ground-based astronomical facilities on Earth. ESO PR Photo 13a/07 ESO PR Photo 13a/07 Cutting the Red Ribbon The ceremony, known as 'Tijerales' in Chile, is the equivalent to the 'roof-topping ceremony' that takes place worldwide, in one form or another, to celebrate reaching the highest level of a construction. It this case, the construction is the unique ALMA Operations Support Facility (OSF), located near the town of San Pedro de Atacama. "The end of this first stage represents an historic moment for ALMA," said Hans Rykaczewski, the European ALMA Project Manager. "Once completed in December 2007, this monumental building of 7,000 square metres will be one of the largest and most important astronomical operation centres in the world." ALMA, located at an elevation of 5,000m in the Atacama Desert of northern Chile, will provide astronomers with the world's most advanced tool for exploring the Universe at millimetre and submillimetre wavelengths. ALMA will detect fainter objects and be able to produce much higher-quality images at these wavelengths than any previous telescope system. The OSF buildings are designed to suit the requirements of this exceptional observatory in a remote, desert location. The facility, which will host about 100 people during operations, consists of three main buildings: the technical building, hosting the control centre of the observatory, the antenna assembly building, including four antenna foundations for testing and maintenance purposes, and the warehouse building, including mechanical workshops. Further secondary buildings are the transporter shelters and the vehicle maintenance facilities as well as the ALMA gate house. The construction started in August 2006 and will be completed in December 2007. ESO PR Photo 13b/07 ESO PR Photo 13b/07 The Ceremony The ceremony took place in the presence of representatives of the regional authorities, members of the Chilean Parliament, and representatives of the local community, including the mayor of San Pedro, Ms. Sandra Berna, who joined more than 40 representatives of ESO, NRAO and NAOJ - the organisations that are, together, building ALMA. "This is certainly a big step in the realisation of the ALMA Project. The completion of this facility will be essential for assembly, testing and adjustment as well as operation and maintenance of all ALMA antennas from Europe, North America and from Japan," said Ryusuke Ogasawara, the representative of NAOJ in Chile. "This is a tremendous achievement and represents a major milestone for the ALMA project," said Adrian Russell, North American Project Manager for ALMA. ESO PR Photo 13c/07 ESO PR Photo 13c/07 The OSF (Artist's View) The first ALMA antennas, the prototypes of which successfully achieved their first combined astronomical observation last week, are expected to arrive at the ALMA site in a few months. These huge antennas will travel in pieces from Europe, USA and Japan and will be assembled next to the OSF building. The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership among Europe, Japan and North America, in cooperation with the Republic of Chile. ALMA is funded in Europe by the European Organisation for Astronomical Research in the Southern Hemisphere, in Japan by the National Institutes of Natural Sciences (NINS) in cooperation with the Academia Sinica in Taiwan and in North America by the U.S. National Science Foundation (NSF) in cooperation with the National Research Council of Canada (NRC). ALMA construction and operations are led on behalf of Europe by ESO, on behalf of Japan by the National Astronomical Observatory of Japan (NAOJ) and on behalf of North America by the National Radio Astronomy Observatory (NRAO), which is managed by Associated Universities, Inc. (AUI)

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

    SciTech Connect

    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 designs. Numerical simulations were performed to investigate the mechanisms of modern roof bolting systems including both the tension and fully grouted bolts. Parameters to be studied are: bolt length, bolt spacing, bolt size/strength, grout annulus, in-situ stress condition, overburden depth, and roof geology (massive strata, fractured, and laminated or thinly-bedded). Based on the analysis of the mechanisms of both bolting systems and failure modes of the bolted strata, roof bolting design criteria and programs for modern roof bolting systems were developed. These criterion and/or programs were combined with the MRGIS for use in conjunction with roof bolt installation.

  11. Simulating Nonlinear Deformations of Solar Sail Membranes Using Explicit Time Integration

    NASA Technical Reports Server (NTRS)

    Wang, John T.; Chen, Tzikang; Sleight, David W.; Tessler, Alex

    2004-01-01

    In this study, the explicit time integration method is employed to predict deformation of highly flexible solar sail structural components. The nonlinear static analysis of a highly flexible ribbon structure is presented to demonstrate the need for having the explicit time integration method in the analysis toolbox for solar sail. Static analyses of the ribbon structure produce ambiquous results whereas the explicit time integration method determines the correct results. Extensive benchmarking examples are also presented to build confidence in the use of the explicit method. Previously determined nonlinear wrinkling deformations of solar sail membranes are found by the explicit method. As the explicit method is known to often require more computational time than nonlinear static methods, a study on mass scaling was also conducted. The computational times are reported for the nonlinear static and explicit time integration solutions to calibrate the advantage of using mass scaling for these problems.

  12. Habitat connectivity shapes urban arthropod communities: the key role of green roofs.

    PubMed

    Braaker, S; Ghazoul, J; Obrist, M K; Moretti, M

    2014-04-01

    The installation of green roofs, defined here as rooftops with a shallow soil cover and extensive vegetation, has been proposed as a possible measure to mitigate the loss of green space caused by the steady growth of cities. However, the effectiveness of green roofs in supporting arthropod communities, and the extent to which they facilitate connectivity of these communities within the urban environment is currently largely unknown. We investigated the variation of species community composition (beta diversity) of four arthropod groups with contrasting mobility (Carabidae, Araneae, Curculionidae, and Apidae) on 40 green roofs and 40 extensively managed green sites on the ground in the city of Zurich, Switzerland. With redundancy analysis and variation partitioning, we (1) disentangled the relative importance of local environmental conditions, the surrounding land cover composition, and habitat connectivity on species community composition, (2) searched for specific spatial scales of habitat connectivity for the different arthropod groups, and (3) discussed the ecological and functional value of green roofs in cities. Our study revealed that on green roofs community composition of high-mobility arthropod groups (bees and weevils) were mainly shaped by habitat connectivity, while low-mobility arthropod groups (carabids and spiders) were more influenced by local environmental conditions. A similar but less pronounced pattern was found for ground communities. The high importance of habitat connectivity in shaping high-mobility species community composition indicates that these green roof communities are substantially connected by the frequent exchange of individuals among surrounding green roofs. On the other hand, low-mobility species communities on green roofs are more likely connected to ground sites than to other green roofs. The integration of green roofs in urban spatial planning strategies has great potential to enable higher connectivity among green spaces, so that eventually even communities of low-mobility species become connected. Furthermore, improving the design of green roofs (composition and configuration of vegetation and soil types) could enhance the ecological value, particularly for low-mobility species. PMID:24933819

  13. Life-cycle cost-benefit analysis of extensive vegetated roof systems.

    PubMed

    Carter, Timothy; Keeler, Andrew

    2008-05-01

    The built environment has been a significant cause of environmental degradation in the previously undeveloped landscape. As public and private interest in restoring the environmental integrity of urban areas continues to increase, new construction practices are being developed that explicitly value beneficial environmental characteristics. The use of vegetation on a rooftop--commonly called a green roof--as an alternative to traditional roofing materials is an increasingly utilized example of such practices. The vegetation and growing media perform a number of functions that improve environmental performance, including: absorption of rainfall, reduction of roof temperatures, improvement in ambient air quality, and provision of urban habitat. A better accounting of the green roof's total costs and benefits to society and to the private sector will aid in the design of policy instruments and educational materials that affect individual decisions about green roof construction. This study uses data collected from an experimental green roof plot to develop a benefit cost analysis (BCA) for the life cycle of extensive (thin layer) green roof systems in an urban watershed. The results from this analysis are compared with a traditional roofing scenario. The net present value (NPV) of this type of green roof currently ranges from 10% to 14% more expensive than its conventional counterpart. A reduction of 20% in green roof construction cost would make the social NPV of the practice less than traditional roof NPV. Considering the positive social benefits and relatively novel nature of the practice, incentives encouraging the use of this practice in highly urbanized watersheds are strongly recommended. PMID:17368704

  14. Integrating solar energy and climate research into science education

    NASA Astrophysics Data System (ADS)

    Betts, Alan K.; Hamilton, James; Ligon, Sam; Mahar, Ann Marie

    2016-01-01

    This paper analyzes multi-year records of solar flux and climate data from two solar power sites in Vermont. We show the inter-annual differences of temperature, wind, panel solar flux, electrical power production, and cloud cover. Power production has a linear relation to a dimensionless measure of the transmission of sunlight through the cloud field. The difference between panel and air temperatures reaches 24°C with high solar flux and low wind speed. High panel temperatures that occur in summer with low wind speeds and clear skies can reduce power production by as much as 13%. The intercomparison of two sites 63 km apart shows that while temperature is highly correlated on daily (R2=0.98) and hourly (R2=0.94) timescales, the correlation of panel solar flux drops markedly from daily (R2=0.86) to hourly (R2=0.63) timescales. Minimum temperatures change little with cloud cover, but the diurnal temperature range shows a nearly linear increase with falling cloud cover to 16°C under nearly clear skies, similar to results from the Canadian Prairies. The availability of these new solar and climate datasets allows local student groups, a Rutland High School team here, to explore the coupled relationships between climate, clouds, and renewable power production. As our society makes major changes in our energy infrastructure in response to climate change, it is important that we accelerate the technical education of high school students using real-world data.

  15. Spatial environmental heterogeneity affects plant growth and thermal performance on a green roof.

    PubMed

    Buckland-Nicks, Michael; Heim, Amy; Lundholm, Jeremy

    2016-05-15

    Green roofs provide ecosystem services, including stormwater retention and reductions in heat transfer through the roof. Microclimates, as well as designed features of green roofs, such as substrate and vegetation, affect the magnitude of these services. Many green roofs are partially shaded by surrounding buildings, but the effects of this within-roof spatial environmental heterogeneity on thermal performance and other ecosystem services have not been examined. We quantified the effects of spatial heterogeneity in solar radiation, substrate depth and other variables affected by these drivers on vegetation and ecosystem services in an extensive green roof. Spatial heterogeneity in substrate depth and insolation were correlated with differential growth, survival and flowering in two focal plant species. These effects were likely driven by the resulting spatial heterogeneity in substrate temperature and moisture content. Thermal performance (indicated by heat flux and substrate temperature) was influenced by spatial heterogeneity in vegetation cover and substrate depth. Areas with less insolation were cooler in summer and had greater substrate moisture, leading to more favorable conditions for plant growth and survival. Spatial variation in substrate moisture (7%-26% volumetric moisture content) and temperature (21°C-36°C) during hot sunny conditions in summer could cause large differences in stormwater retention and heat flux within a single green roof. Shaded areas promote smaller heat fluxes through the roof, leading to energy savings, but lower evapotranspiration in these areas should reduce stormwater retention capacity. Spatial heterogeneity can thus result in trade-offs between different ecosystem services. The effects of these spatial heterogeneities are likely widespread in green roofs. Structures that provide shelter from sun and wind may be productively utilized to design higher functioning green roofs and increase biodiversity by providing habitat heterogeneity. PMID:26901799

  16. Integrally regulated solar array demonstration using an Intel 8080 microprocessor

    NASA Technical Reports Server (NTRS)

    Petrik, E. J.

    1977-01-01

    A concept for regulating the voltage of a solar array by using a microprocessor to effect discrete voltage changes was demonstrated. Eight shorting switches were employed to regulate a simulated array at set-point voltages between 10,000 and 15,000 volts. The demonstration showed that the microprocessor easily regulated the solar array output voltage independently of whether or not the switched cell groups were binary sized in voltage. In addition, the microprocessor provided logic memory capability to perform additional tasks such as locating and insolating a faulty switch.

  17. Hydrological Response of Sedum-Moss Roof

    NASA Astrophysics Data System (ADS)

    Bengtsson, L.

    2004-12-01

    Eco-roofs are becoming popular for aesthetic reasons and also as units of stormwater systems. It is thought that such roofs with soil cover and vegetation reduces the total runoff, the peak flows and improves the quality of the roof water. Here are reported investigations of runoff from thin, 3-4 cm soil, extensive green roofs with sedum-moss in southern Sweden. The two-year study was performed on new roofs in the eco-city Augustenborg and also on nearby old vegetative roofs. The rain intensity and the roof runoff were measured with 5 min, or in some experiments with 1 min, resolution. The annual runoff from the eco-roofs was about half that from hard roofs and was close to that of small natural rivers. However, although most rainy days there was no or little runoff from the roofs, the highest observed daily runoff values were close to the daily rainfall. Runoff is initiated, when the soil is at field capacity. Thereafter the hourly runoff corresponds closely to the hourly rainfall. For short-term high intensity storms, the runoff peak is attenuated relative the rain intensity. The time of concentration for runoff was experimentally determined applying artificial rains on existing roofs and on experimental roof plots with varying slopes and using different drainage layers. The peak runoff from the roofs was found to correspond to the rain intensity over 20-30 minutes. The probability of high rain intensity is much higher than the probability of high runoff. When intensity-duration-frequency curves were constructed, runoff with 0.4 year return period corresponded to rain with 1.5 year return period. The influence of the slope of the roofs on the runoff peak was minor as was the effect of drainage layer. The vertical flow in the soil dominates the runoff process. The influence of extensive sedum-moss vegetated roofs on runoff quality was also studied to ascertain whether vegetated roofs behave as sink or source of pollutants and whether the runoff quality changes with roof age. The results show that in general vegetated roofs behave as a source of contaminants. With the exception of a 15-year old roof, the studied vegetated roofs contributed phosphate-phosphorus to the runoff. Some metals appeared in concentrations that corresponds to moderately polluted water. However, nitrate-nitrogen is retained by the vegetation and the soil.

  18. An Integrative STEM Aproach to Teaching Solar Energy Collection

    ERIC Educational Resources Information Center

    Hughes, Bill; Mona, Lynn; Stout, Heath; Bierly, Mike; McAninch, Steve

    2015-01-01

    "Against the backdrop of the daunting carbon-neutral energy needs of our global future, the largest gap between our present use of solar energy and its enormous undeveloped potential defines a compelling imperative for science and technology in the 21st century" (Lewis & Norcera 2006). Concurrently, the United States educational…

  19. Western Wind and Solar Integration Study: Executive Summary

    SciTech Connect

    none,

    2010-05-01

    This Study investigates the operational impact of up to 35% energy penetration of wind, photovoltaics (PVs), and concentrating solar power (CSP) on the power system operated by the WestConnect group of utilities in Arizona, Colorado, Nevada, New Mexico, and Wyoming.

  20. An Integrative STEM Aproach to Teaching Solar Energy Collection

    ERIC Educational Resources Information Center

    Hughes, Bill; Mona, Lynn; Stout, Heath; Bierly, Mike; McAninch, Steve

    2015-01-01

    "Against the backdrop of the daunting carbon-neutral energy needs of our global future, the largest gap between our present use of solar energy and its enormous undeveloped potential defines a compelling imperative for science and technology in the 21st century" (Lewis & Norcera 2006). Concurrently, the United States educational

  1. Condensation Risk of Mechanically Attached Roof Systems in Cold Climate Zones

    SciTech Connect

    Pallin, Simon B

    2013-01-01

    A white roof, cool roof, is constructed to decrease thermal loads from solar radiation, therefore saving energy by decreasing the cooling demands. Unfortunately, cool roofs with mechanically attached membrane, have shown to have a higher risk of intermediate condensation in the materials below the membrane in certain climates (Ennis & Kehrer, 2011) and in comparisons with similar construction with a darker exterior surface (Bludau, Zirkelbach, & Kuenzel, 2009). As a consequence, questions have been raised regarding the sustainability and reliability of using cool roof membranes in Northern U.S. climate zones. A white roof surface reflects more of the incident solar radiation in comparisons with a dark surface, which makes a distinguished difference on the surface temperature of the roof. However, flat roofs with either a light or dark surface and if facing a clear sky, are constantly losing energy to the sky due to the exchange of infrared radiation. This phenomenon exists both during the night and the day. During the day, if the sun shines on the roof surface, the exchange of infrared radiation typically becomes insignificant. During nights and in cold climates, the temperature difference between the roof surface and the sky can deviate up to 20 C (Hagentoft, 2001) which could result in a very cold surface temperature compared to the ambient temperature. Further, a colder surface temperature of the roof increases the energy loss and the risk of condensation in the building materials below the membrane. In conclusion, both light and dark coated roof membranes are cooled by the infrared radiation exchange during the night, though a darker membrane is more heated by the solar radiation during the day, thus decreasing the risk of condensation. The phenomenon of night time cooling from the sky and the lack of solar gains during the day is not likely the exclusive problem concerning the risk of condensation in cool roofs with mechanically attached membranes. Roof systems with thermoplastic membranes are prone to be more effected by interior air intrusion into the roof construction; both due to the wind induced pressure differences and due to the flexibility and elasticity of the membrane (Molleti, Baskaran, Kalinger, & Beaulieu, 2011). Depending on the air permeability of the material underneath the membrane, wind forces increase the risk of fluttering (also referred as billowing) of the thermoplastic membrane. Expectably, the wind induced pressure differences creates a convective air flow into the construction i.e. Page 2 air intrusion. If the conditions are right, moisture from the exchanging air may condensate on surfaces with a temperature below dew-point. The definite path of convective airflows through the building envelope is usually very difficult to determine and therefore simplified models (K nzel, Zirkelbach, & Scfafaczek, 2011) help to estimate an additional moisture loads as a result of the air intrusion. The wind uplifting pressure in combination with wind gusts are important factors for a fluttering roof. Unfortunately, the effect from a fluctuating wind is difficult to estimate as this is a highly dynamic phenomenon and existing standards (ASTM, 2011a) only take into account a steady state approach i.e. there is no guidance or regulations on how to estimate the air intrusion rate. Obviously, a more detailed knowledge on the hygrothermal performance of mechanically attached cool roof system is requested; in consideration to varying surface colors, roof air tightness, climate zones and indoor moisture supply.

  2. Roof control strategies for underground coal mines. Information circular/1993

    SciTech Connect

    Smith, W.C.

    1993-01-01

    The U.S. Bureau of Mines report presents a general overview of roof bolting and other roof support methods used in the United States. Characteristics of bad roof and associated roof failure theories are briefly presented as background to roof support. Methods of detecting and monitoring roof behavior and/or bolt performance provide essential feedback on roof support requirements. A discussion follows on roof bolt design that assimilates roof and support parameters into useful equations or nomographs to help decide what bolt types to use and how they should be installed under different roof conditions.

  3. Multifunctional integration of thin-film silicon solar cells on carbon-fiber-reinforced epoxy composites

    SciTech Connect

    Jason Maung, K.; Hahn, H. Thomas; Ju, Y.S.

    2010-03-15

    Multifunction integration of solar cells in load-bearing structures can enhance overall system performance by reducing parasitic components and material redundancy. The article describes a manufacturing strategy, named the co-curing scheme, to integrate thin-film silicon solar cells on carbon-fiber-reinforced epoxy composites and eliminate parasitic packaging layers. In this scheme, an assembly of a solar cell and a prepreg is cured to form a multifunctional composite in one processing step. The photovoltaic performance of the manufactured structures is then characterized under controlled cyclic mechanical loading. The study finds that the solar cell performance does not degrade under 0.3%-strain cyclic tension loading up to 100 cycles. Significant degradation, however, is observed when the magnitude of cyclic loading is increased to 1% strain. The present study provides an initial set of data to guide and motivate further studies of multifunctional energy harvesting structures. (author)

  4. The Western Wind and Solar Integration Study Phase 2 (Fact Sheet)

    SciTech Connect

    2013-09-01

    This fact sheet is a basic overview of the Western Wind and Solar Integration Study, Phase 2. The electric grid is a highly complex, interconnected machine, and changing one part of the grid can have consequences elsewhere. Adding wind and solar affects the operation of the other power plants and adding high penetrations can induce cycling of fossil-fueled generators. Cycling leads to wear-and-tear costs and changes in emissions.

  5. Flexible Thin-Film Silicon Solar Cells

    SciTech Connect

    Vijh, Aarohi; Cao, Simon; Mohring, Brad

    2014-01-11

    High fuel costs, environmental concerns and issues of national energy security have brought increasing attention to a distributed generation program for electricity based on solar technology. Rooftop photovoltaic (PV) systems provide distributed generation since the power is consumed at the point of production, thus eliminating the need for costly additional transmission lines. However, most current photovoltaic modules are heavy and require a significant amount of labor and accessory hardware such as mounting frames for installation on rooftops. This makes rooftop systems impractical or cost prohibitive in many instances. Under this project, Xunlight has advanced its manufacturing process for the production of lightweight, flexible thin-film silicon based photovoltaic modules, and has enhanced the reliability and performance of Xunlight’s products. These modules are easily unrolled and adhered directly to standard commercial roofs without mounting structures or integrated directly into roofing membrane materials for the lowest possible installation costs on the market. Importantly, Xunlight has now established strategic alliances with roofing material manufacturers and other OEMs for the development of building integrated photovoltaic roofing and other PV-enabled products, and has deployed its products in a number of commercial installations with these business partners.

  6. Evaluating convex roof entanglement measures.

    PubMed

    Tóth, Géza; Moroder, Tobias; Gühne, Otfried

    2015-04-24

    We show a powerful method to compute entanglement measures based on convex roof constructions. In particular, our method is applicable to measures that, for pure states, can be written as low order polynomials of operator expectation values. We show how to compute the linear entropy of entanglement, the linear entanglement of assistance, and a bound on the dimension of the entanglement for bipartite systems. We discuss how to obtain the convex roof of the three-tangle for three-qubit states. We also show how to calculate the linear entropy of entanglement and the quantum Fisher information based on partial information or device independent information. We demonstrate the usefulness of our method by concrete examples. PMID:25955038

  7. Solar Reserve Methodology for Renewable Energy Integration Studies Based on Sub-Hourly Variability Analysis: Preprint

    SciTech Connect

    Ibanez, E.; Brinkman, G.; Hummon, M.; Lew, D.

    2012-08-01

    Increasing penetrations of wind a solar energy are raising concerns among electric system operators because of the variability and uncertainty associated with power sources. Previous work focused on the quantification of reserves for systems with wind power. This paper presents a new methodology that allows the determination of necessary reserves for high penetrations of photovoltaic (PV) power and compares it to the wind-based methodology. The solar reserve methodology is applied to Phase 2 of the Western Wind and Solar Integration Study. A summary of the results is included.

  8. Lightweight Integrated Solar Array and Transceiver. [Improving Electrical Power and Communication Capabilities in Small Spacecraft

    NASA Technical Reports Server (NTRS)

    Carr, John; Martinez, Andres; Petro, Andrew

    2015-01-01

    The Lightweight Integrated Solar Array and Transceiver (LISA-T) project will leverage several existing and on-going efforts at Marshall Space Flight Center (MSFC) for the design, development, fabrication, and test of a launch stowed, orbit deployed structure on which thin-film photovoltaics for power generation and antenna elements for communication, are embedded. Photovoltaics is a method for converting solar energy into electricity using semiconductor materials. The system will provide higher power generation with a lower mass, smaller stowage volume, and lower cost than the state of the art solar arrays, while simultaneously enabling deployable antenna concepts.

  9. Integrated Modeling of Building Energy Requirements IncorporatingSolar Assisted Cooling

    SciTech Connect

    Firestone, Ryan; Marnay, Chris; Wang, Juan

    2005-08-10

    This paper expands on prior Berkeley Lab work on integrated simulation of building energy systems by the addition of active solar thermal collecting devices, technology options not previously considered (Siddiqui et al 2005). Collectors can be used as an alternative or additional source of hot water to heat recovery from reciprocating engines or microturbines. An example study is presented that evaluates the operation of solar assisted cooling at a large mail sorting facility in southern California with negligible heat loads and year-round cooling loads. Under current conditions solar thermal energy collection proves an unattractive option, but is a viable carbon emission control strategy.

  10. Global Cooling: Policies to Cool the World and Offset Global Warming from CO2 Using Reflective Roofs and Pavements

    SciTech Connect

    Akbari, Hashem; Levinson, Ronnen; Rosenfeld, Arthur; Elliot, Matthew

    2009-08-28

    Increasing the solar reflectance of the urban surface reduce its solar heat gain, lowers its temperatures, and decreases its outflow of thermal infrared radiation into the atmosphere. This process of 'negative radiative forcing' can help counter the effects of global warming. In addition, cool roofs reduce cooling-energy use in air conditioned buildings and increase comfort in unconditioned buildings; and cool roofs and cool pavements mitigate summer urban heat islands, improving outdoor air quality and comfort. Installing cool roofs and cool pavements in cities worldwide is a compelling win-win-win activity that can be undertaken immediately, outside of international negotiations to cap CO{sub 2} emissions. We propose an international campaign to use solar reflective materials when roofs and pavements are built or resurfaced in temperate and tropical regions.

  11. Can Integrated Micro-Optical Concentrator Technology Revolutionize Flat-Plate Photovoltaic Solar Energy Harvesting?

    NASA Astrophysics Data System (ADS)

    Haney, Michael W.

    2015-12-01

    The economies-of-scale and enhanced performance of integrated micro-technologies have repeatedly delivered disruptive market impact. Examples range from microelectronics to displays to lighting. However, integrated micro-scale technologies have yet to be applied in a transformational way to solar photovoltaic panels. The recently announced Micro-scale Optimized Solar-cell Arrays with Integrated Concentration (MOSAIC) program aims to create a new paradigm in solar photovoltaic panel technology based on the incorporation of micro-concentrating photo-voltaic (μ-CPV) cells. As depicted in Figure 1, MOSAIC will integrate arrays of micro-optical concentrating elements and micro-scale PV elements to achieve the same aggregated collection area and high conversion efficiency of a conventional (i.e., macro-scale) CPV approach, but with the low profile and mass, and hopefully cost, of a conventional non-concentrated PV panel. The reduced size and weight, and enhanced wiring complexity, of the MOSAIC approach provide the opportunity to access the high-performance/low-cost region between the conventional CPV and flat-plate (1-sun) PV domains shown in Figure 2. Accessing this portion of the graph in Figure 2 will expand the geographic and market reach of flat-plate PV. This talk reviews the motivation and goals for the MOSAIC program. The diversity of the technical approaches to micro-concentration, embedded solar tracking, and hybrid direct/diffuse solar resource collection found in the MOSAIC portfolio of projects will also be highlighted.

  12. Demonstration of energy savings of cool roofs

    SciTech Connect

    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.

  13. Integral: collector solar greenhouse using solar membrane and external rock storage

    SciTech Connect

    Droll, P.W.

    1980-12-31

    The results of a three-year study to evaluate engineering aspects of converting a commercial greenhouse to more effectively used solar energy as a heating source are summarized. The solar retrofit greenhouse and nine other similar buildings are located in northern California. They are large Quonset style greenhouses glazed on all curved surfaces with a conventional corrugated fiberglass covering. The solar retrofit building was modified in 1978 by installing on the inside surface of the original corrugated fiberglass three air-separated layers of a material called Solar Membrane which reduces convective losses through the overlapping fiberglass panels and effectively prevents long wave infrared transmission out of the greenhouse. A large above-ground rock storage bin was also constructed. Two control buildings were also monitored, one for two years, and the second for only the second year. The measured values of electrical and gas consumption indicate that the modified solar building: (1) used less than 50% of the gas by the two-year control building, and (2) used 40% less gas than the one-year control building. Detailed mechanical design data are included, along with a development of the computer program used to predict actual modified and unmodified greenhouse performance. Good agreement was obtained between actual performance and the theoretical values predicted by the simulation. (LEW)

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

    SciTech Connect

    Syd S. Peng

    2001-07-15

    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. In this quarter, retrofitting work to build a dedicated roof bolter for this research has been started. A number of numerical methods have been developed to improve the quality of and to analyze the collected drilling parameters. Finite element modeling of roof bolting mechanism is continuing.

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

    SciTech Connect

    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.

  16. Tracking-integrated optics: applications in solar concentration

    NASA Astrophysics Data System (ADS)

    Wheelwright, Brian M.; Angel, Roger; Coughenour, Blake

    2014-12-01

    Conventional concentrating photovoltaic (CPV) systems track the sun with high precision dual-axis trackers. The emergent field of tracking-integrated optics has the potential to simplify the mechanics of CPV systems by loosening or eliminating the need for dual-axis tracking. In a tracking-integrated scheme, external module tracking is complemented or entirely replaced by miniature tracking within the module. This internal tracking-integration may take the form of active small-motion translation, rotation of arrayed optics, or by passive material property changes induced by the concentrated light. These methods are briefly reviewed. An insolation weighting model is presented which will aid in the design of tracking-integrated optics by quantifying the tradeoff between angular operation range and annual sunlight collection. We demonstrate that when tracking-integrated optics are used to complement external module tracking about a horizontal, North-South oriented axis, truncating the operational range may be advantageous. At Tucson AZ latitude (32.2°N), 15.6% of the angular range may be truncated while only sacrificing 3.6% of the annual insolation. We show that modules tracked about a polar-aligned axis are poorly-suited for truncation.

  17. A Fully Integrated Nanosystem of Semiconductor Nanowires for Direct Solar Water Splitting

    SciTech Connect

    Liu, Chong; Tang, Jinyao; Chen, HaoMing; Liu, Bin; Yang, Peidong

    2013-02-21

    Artificial photosynthesis, the biomimetic approach to converting sunlight?s energy directly into chemical fuels, aims to imitate nature by using an integrated system of nanostructures, each of which plays a specific role in the sunlight-to-fuel conversion process. Here we describe a fully integrated system of nanoscale photoelectrodes assembled from inorganic nanowires for direct solar water splitting. Similar to the photosynthetic system in a chloroplast, the artificial photosynthetic system comprises two semiconductor light absorbers with large surface area, an interfacial layer for charge transport, and spatially separated cocatalysts to facilitate the water reduction and oxidation. Under simulated sunlight, a 0.12percent solar-to-fuel conversion efficiency is achieved, which is comparable to that of natural photosynthesis. The result demonstrates the possibility of integrating material components into a functional system that mimics the nanoscopic integration in chloroplasts. It also provides a conceptual blueprint of modular design that allows incorporation of newly discovered components for improved performance.

  18. The Solar System/El Sistema Solar--A Fully Integrated Instructional Unit.

    ERIC Educational Resources Information Center

    Van Heukelem, Tom; Mercado, Maria de Jesus

    This lesson plan for the second grade uses information on the solar system to provide science education for limited-English-proficient (LEP) students in San Diego, California. The lesson has been developed to be taught in a bilingual class, a Spanish-language immersion class, or a two-way bilingual class. Lessons are arranged so that native…

  19. Conceptual design and techno-economic assessment of integrated solar combined cycle system with DSG technology

    SciTech Connect

    Nezammahalleh, H.; Farhadi, F.; Tanhaemami, M.

    2010-09-15

    Direct steam generation (DSG) in parabolic trough collectors causes an increase to competitiveness of solar thermal power plants (STPP) by substitution of oil with direct steam generation that results in lower investment and operating costs. In this study the integrated solar combined cycle system with DSG technology is introduced and techno-economic assessment of this plant is reported compared with two conventional cases. Three considered cases are: an integrated solar combined cycle system with DSG technology (ISCCS-DSG), a solar electric generating system (SEGS), and an integrated solar combined cycle system with HTF (heat transfer fluid) technology (ISCCS-HTF). This study shows that levelized energy cost (LEC) for the ISCCS-DSG is lower than the two other cases due to reducing O and M costs and also due to increasing the heat to electricity net efficiency of the power plant. Among the three STPPs, SEGS has the lowest CO{sub 2} emissions, but it will operate during daytime only. (author)

  20. 24 CFR 3280.402 - Test procedures for roof trusses.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 5 2014-04-01 2014-04-01 false Test procedures for roof trusses... procedures for roof trusses. (a) Roof load tests. This section provides the roof truss test procedure for vertical loading conditions. Where roof trusses act as support for other members, have eave or...

  1. Downscaling Solar Power Output to 4-Seconds for Use in Integration Studies (Presentation)

    SciTech Connect

    Hummon, M.; Weekley, A.; Searight, K.; Clark, K.

    2013-10-01

    High penetration renewable integration studies require solar power data with high spatial and temporal accuracy to quantify the impact of high frequency solar power ramps on the operation of the system. Our previous work concentrated on downscaling solar power from one hour to one minute by simulation. This method used clearness classifications to categorize temporal and spatial variability, and iterative methods to simulate intra-hour clearness variability. We determined that solar power ramp correlations between sites decrease with distance and the duration of the ramp, starting at around 0.6 for 30-minute ramps between sites that are less than 20 km apart. The sub-hour irradiance algorithm we developed has a noise floor that causes the correlations to approach ~0.005. Below one minute, the majority of the correlations of solar power ramps between sites less than 20 km apart are zero, and thus a new method to simulate intra-minute variability is needed. These intra-minute solar power ramps can be simulated using several methods, three of which we evaluate: a cubic spline fit to the one-minute solar power data; projection of the power spectral density toward the higher frequency domain; and average high frequency power spectral density from measured data. Each of these methods either under- or over-estimates the variability of intra-minute solar power ramps. We show that an optimized weighted linear sum of methods, dependent on the classification of temporal variability of the segment of one-minute solar power data, yields time series and ramp distributions similar to measured high-resolution solar irradiance data.

  2. Downscaling Solar Power Output to 4-Seconds for Use in Integration Studies: Preprint

    SciTech Connect

    Hummon, M.; Weekley, A.; Searight, K.; Clark, K.

    2013-10-01

    High penetration renewable integration studies require solar power data with high spatial and temporal accuracy to quantify the impact of high frequency solar power ramps on the operation of the system. Our previous work concentrated on downscaling solar power from one hour to one minute by simulation. This method used clearness classifications to categorize temporal and spatial variability, and iterative methods to simulate intra-hour clearness variability. We determined that solar power ramp correlations between sites decrease with distance and the duration of the ramp, starting at around 0.6 for 30-minute ramps between sites that are less than 20 km apart. The sub-hour irradiance algorithm we developed has a noise floor that causes the correlations to approach ~0.005. Below one minute, the majority of the correlations of solar power ramps between sites less than 20 km apart are zero, and thus a new method to simulate intra-minute variability is needed. These intra-minute solar power ramps can be simulated using several methods, three of which we evaluate: a cubic spline fit to the one-minute solar power data; projection of the power spectral density toward the higher frequency domain; and average high frequency power spectral density from measured data. Each of these methods either under- or over-estimates the variability of intra-minute solar power ramps. We show that an optimized weighted linear sum of methods, dependent on the classification of temporal variability of the segment of one-minute solar power data, yields time series and ramp distributions similar to measured high-resolution solar irradiance data.

  3. Integral glass encapsulation for solar arrays. Quarterly progress report No. 13

    SciTech Connect

    Landis, Geoffrey A.

    1980-03-01

    Progress on the development of electrostatic bonding as a method of integrally encapsulating silicon solar cells in glass is reported. Efforts for the current phase of this program are to continue to demonstrate process uniformity of encapsulation by electrostatic bonding. An additional goal for this program is to develop preformed contacts as a method of integrating cell processing into the encapsulation procedure, resulting in a low-cost module assembly technique.

  4. Effects of solar cell environment on contact integrity

    NASA Technical Reports Server (NTRS)

    Weizer, Victor G.; Fatemi, Navid S.

    1993-01-01

    The III-V semiconductors react extremely rapidly with most commonly used contact metallizations. This precludes the use of elevated temperatures in the contact formation process for solar cells and other shallow junction devices. These devices must rely upon contact metallizations that are sufficiently conductive in their 'as-fabricated' state. However, while there are a number of non-sintered metallizations that have acceptable characteristics, the lack of a sintering step makes them vulnerable to a variety of environmentally induced degradation processes. The degrading effects resulting from the exposure of unsintered devices to a humid environment and to a vacuum (space) environment are described. It is shown, further, that these effects are magnified by the presence of mechanical damage in the contact metallization. The means to avoid or prevent these degrading interactions are presented.

  5. Tilt optimization of a building integrated solar concentrating unit

    NASA Astrophysics Data System (ADS)

    Chemisana, D.; Tripanagnostopoulos, Y.; Lamnatou, Chr.; Souliotis, M.; Rosell, J. I.; Barrau, J.

    2012-10-01

    The concept of a static linear Fresnel concentrator with a tracking absorber has been simulated and well understood in the past. This paper bridges the gap between theoretical optical performances and operation in outdoor conditions. The effort focuses on the characterization of weather and tilt angle effects on the solar concentrator annual performance. Useful mathematical expressions are derived to show the dependence of the annual concentrated energy on latitude, global radiation, mean clearness index and tilt angle. An equation for the optimization of the annual yield is also proposed. The results are applied to a PVT generator and the annual production of thermal and electrical output energy is evaluated for an installation in Barcelona (Spain). A performance improvement above 5% is reached when the optimized tilt angle is used.

  6. Fabrication of multijunction high voltage concentrator solar cells by integrated circuit technology

    NASA Astrophysics Data System (ADS)

    Valco, G. J.; Kapoor, V. J.; Evans, J. C., Jr.; Chai, A.-T.

    Standard integrated circuit technology has been developed for the design and fabrication of planar multijunction (PMJ) solar cell chips. Each 1 cm x 1 cm solar chip consisted of six n(+)/p, back contacted, internally series interconnected unit cells. These high open circuit voltage solar cells were fabricated on 2 ohm-cm, p-type 75 microns thick, silicon substrates. A five photomask level process employing contact photolithography was used to pattern for boron diffusions, phorphorus diffusions, and contact metallization. Fabricated devices demonstrated an open circuit voltage of 3.6 volts and a short circuit current of 90 mA at 80 AMl suns. An equivalent circuit model of the planar multi-junction solar cell was developed.

  7. Fabrication of multijunction high voltage concentrator solar cells by integrated circuit technology

    NASA Technical Reports Server (NTRS)

    Valco, G. J.; Kapoor, V. J.; Evans, J. C., Jr.; Chai, A.-T.

    1981-01-01

    Standard integrated circuit technology has been developed for the design and fabrication of planar multijunction (PMJ) solar cell chips. Each 1 cm x 1 cm solar chip consisted of six n(+)/p, back contacted, internally series interconnected unit cells. These high open circuit voltage solar cells were fabricated on 2 ohm-cm, p-type 75 microns thick, silicon substrates. A five photomask level process employing contact photolithography was used to pattern for boron diffusions, phorphorus diffusions, and contact metallization. Fabricated devices demonstrated an open circuit voltage of 3.6 volts and a short circuit current of 90 mA at 80 AMl suns. An equivalent circuit model of the planar multi-junction solar cell was developed.

  8. Integration of Semiconducting Sulfides for Full-Spectrum Solar Energy Absorption and Efficient Charge Separation.

    PubMed

    Zhuang, Tao-Tao; Liu, Yan; Li, Yi; Zhao, Yuan; Wu, Liang; Jiang, Jun; Yu, Shu-Hong

    2016-05-23

    The full harvest of solar energy by semiconductors requires a material that simultaneously absorbs across the whole solar spectrum and collects photogenerated electrons and holes separately. The stepwise integration of three semiconducting sulfides, namely ZnS, CdS, and Cu2-x S, into a single nanocrystal, led to a unique ternary multi-node sheath ZnS-CdS-Cu2-x S heteronanorod for full-spectrum solar energy absorption. Localized surface plasmon resonance (LSPR) in the nonstoichiometric copper sulfide nanostructures enables effective NIR absorption. More significantly, the construction of pn heterojunctions between Cu2-x S and CdS leads to staggered gaps, as confirmed by first-principles simulations. This band alignment causes effective electron-hole separation in the ternary system and hence enables efficient solar energy conversion. PMID:27062543

  9. Solar/hydro integration study. Technical progress report, February-July 1980. [STORMRK code

    SciTech Connect

    Not Available

    1980-01-01

    The Water and Power Resources Service in cooperation with the Department of Energy (DOE) is investigating the technical and economic feasibility of integrating solar central receiver powerplants with the Federal hydroelectric power system in the southwest United States. The principal hydro facility in this region is Hoover Dam. It is located on the Colorado River with Lake Mead on the upstream side and Lake Mohave on the downstream side. The central receiver was selected for this application because DOE has identified it as the most economically feasible design for large power systems, i.e., 100-MWe systems or larger. Typical meteorological year (TMY) data were obtained for Las Vegas from the Solar Energy Research Institute. Plots of available solar energy at Yuma and Mormon Mesa are presented for several operational threshold levels. The data show that a solar plant's operational time can be reduced by 20% and still utilize more than 97% of the available solar energy. The Mormon Mesa site has slightly more solar energy available than the Yuma site. A meteorological surface observation network (MESONET) weather station is being prepared for installation at the Yuma site. The MESONET station which normally measures temperature, relative humidity, barometric pressure, wind speed, and wind direction will be retrofitted to measure direct beam and global radiation. The radiation data will be used in dynamic simulations of solar power systems. (WHK)

  10. Development of an integrated heat pipe-thermal storage system for a solar receiver

    NASA Technical Reports Server (NTRS)

    Keddy, E. S.; Sena, J. T.; Merrigan, M. A.; Heidenreich, G.; Johnson, S.

    1987-01-01

    The Organic Rankine Cycle (ORC) Solar Dynamic Power System (SDPS) is one of the candidates for Space Station prime power application. In the low Earth orbit of the Space Station approximately 34 minutes of the 94-minute orbital period is spent in eclipse with no solar energy input to the power system. For this period the SDPS will use thermal energy storage (TES) material to provide a constant power output. An integrated heat-pipe thermal storage receiver system is being developed as part of the ORC-SDPS solar receiver. This system incorporates potassium heat pipe elements to absorb and transfer the solar energy within the receiver cavity. The heat pipes contain the TES canisters within the potassium vapor space with the toluene heater tube used as the condenser region of the heat pipe. During the insolation period of the Earth orbit, solar energy is delivered to the heat pipe in the ORC-SDPS receiver cavity. The heat pipe transforms the non-uniform solar flux incident in the heat pipe surface within the receiver cavity to an essentially uniform flux at the potassium vapor condensation interface in the heat pipe. During solar insolation, part of the thermal energy is delivered to the heater tube and the balance is stored in the TES units. During the eclipse period of the orbit, the balance stored in the TES units is transferred by the potassium vapor to the toluene heater tube.

  11. Low-cost solar array project and Proceedings of the 15th Project Integration Meeting

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Progress made by the Low-Cost Solar Array Project during the period December 1979 to April 1980 is described. Project analysis and integration, technology development in silicon material, large area silicon sheet and encapsulation, production process and equipment development, engineering, and operation are included.

  12. Flat Plate Solar Array Project: Proceedings of the 20th Project Integration Meeting

    NASA Technical Reports Server (NTRS)

    Mcdonald, R. R.

    1982-01-01

    Progress made by the Flat-Plate Solar Array Project during the period November 1981 to April 1982 is reported. Project analysis and integration, technology research in silicon material, large-area silicon sheet and environmental isolation, cell and module formation, engineering sciences, and module performance and failure analysis are covered.

  13. Energy Systems Integration: NREL + SolarCity and the Hawaiian Electric Companies (Fact Sheet)

    SciTech Connect

    Not Available

    2015-02-01

    This fact sheet describes the collaboration between NREL, SolarCity, and the Hawaiian Electric Companies at the Energy Systems Integration Facility (ESIF) to address the safety, reliability, and stability challenges of interconnecting high penetrations of distributed photovoltaics with the electric power system.

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

    SciTech Connect

    Syd S. Peng

    2003-07-15

    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. In this quarter, the field, theoretical and programming works have been performed toward achieving the research goals set in the proposal. The selected site and the field testing plan enabled us to test all three aspects of roof geological features. The development of the data interpretation methodologies and the geology mapping computer program have also been preceding well.

  15. The solar cube: A building-integrated photovoltaic incubator

    SciTech Connect

    Perlin, J.

    2000-06-01

    A huge tipped glass tube provides instruction to visitors to the Discovery Science Center in Los Angeles, and an educational diversion to commuters on Interstate 5. The project revealed that photovoltaic industry has a lot to learn from those in the construction industry about building-integrated photovoltaics. The industry must develop products pleasing to the architect and the architect's client, and easily adaptable to the rest of the building. This market requires PV manufacturers to look at photovoltaics as a building material that just so happens to produce electricity, too. Hence, price per square rules in this application over cost per watt. Most importantly, of course, demonstrating as pioneers the potential of building-integrated photovoltaics has delighted the client, The Science Discovery Center.

  16. Method of making static solar heat collectors

    SciTech Connect

    Brill-Edwards, K.O.P.

    1983-09-20

    A load-bearing building panel capable of forming an external wall cladding or roof component has a solar heat collecting capacity in the form of channels for heat exchange fluid incorporated in the fabric of the panel. The panel is made of a structural plastics material, such as G.R.P. laminate, successive layers being moulded to simulate tiles. On the back or underside, longitudinal reinforcing beams are built in during laying up of the panel. Between the beams cores or formers defining a matrix or channels are encapsulated in layers of the G.R.P. Wax cores are melted or dissolved out after curing of the panel; metal formers remain embedded in the fabric of the panel. The matrix is connected by flow and return pipes to a heat exchange system within the building. Panels intended for roofing have ridge flanges and wall plates moulded into the substrate at the appropriate pitch angle, and a split capping tube embraces the ridge flanges. A pitched roof formed by oppositely sloping panels is self-supporting. An integral box girder can also be formed across the underside of the panel at the eaves to rest on the top of the external wall to be loaded with concrete in situ so as to anchor the roof on the walls.

  17. Integration between solar and space science data for space weather forecast using web services

    NASA Astrophysics Data System (ADS)

    Kato, S.

    2007-08-01

    As the technology develops, the opportunity that the human beings behave in space, and it is still understood that the solar activities (especially the solar flare) influence the airlines communication, the ship communication and the power generator of the electric power company, etc. Forecasting the effects of the solar activities is becoming very important because there is such a background. Our goal is that constructs the detailed model from the Sun to the magnetosphere of the earth and simulates the solar activities and the effects. We try to integrate the existing observational data including the ground observational data and satellite observational data using by web service technology as a base to construct the model. We introduce our activity to combine the solar and space science data in Japan. Methods Generally, it is difficult to develop the virtual common database, but web service makes interconnection among different databases comparatively easy. We try to connect some databases in the portal site. Each different data objects is aggregated to a common data object. We can develop more complex services. We use RELAX NG in order to develop these applications easily. We begin the trial of the interconnection among the solar and space science data in Japan. In the case of solar observational data, we find the activity such as VO, for example, VSO and EGSO, but space science data seems to be very complex. In addition to this, there is time lag that solar activity has an effect on the magnetosphere of the Earth. We discuss these characteristic in the data analysis between the solar and space data. This work was supported by the Grant-in-Aid for Creative Scientific Research `The Basic Study of Space Weather Prediction' (17GS0208) from the Ministry of Education, Science, Sports, Technology, and Culture of Japan

  18. Reduced Graphene Oxide Bipolar Membranes for Integrated Solar Water Splitting in Optimal pH.

    PubMed

    McDonald, Michael B; Bruce, Jared P; McEleney, Kevin; Freund, Michael S

    2015-08-24

    The integration of light absorbers and catalysts for the water splitting process requires a membrane capable of both ion and electron management and product separation to realize efficient solar fuels systems. Bipolar membranes can maintain a pH gradient for optimal reaction conditions by the dissociation of water. Such membranes that contain graphene in the interfacial layer are fabricated by the chemical reduction of a uniformly deposited graphene oxide layer to convert sp(3) catalyst regions to sp(2) conductive regions. The resulting electrical and water dissociation properties are optimized by adjusting the exposure conditions, and treatments of less than 5 min render an interface that exceeds the conductivity requirements for integrated solar water splitting and increases the overpotential by <0.3 V. Integration with photoelectrodes is examined by characterizing the electrical interface formed between graphene and Si microwires, and we found that efficient Ohmic junctions are possible. PMID:26204850

  19. Sloshing impact in roofed tanks

    SciTech Connect

    Uras, R.A.

    1995-12-31

    A large number of high-level waste (HLW) storage tanks exists in various tank farms. Seismic activities at those locations may cause significant sloshing in HLW tanks. These tanks are covered to avoid any spilling during large amplitude earthquakes. However, large amplitude sloshing may result in impact on the cover or the roof of the tank. Hence, a better understanding of the impact phenomenon is necessary to assess the safety of the tanks currently in existence, and to establish design guidelines for future designs. A pressure based formulation is derived to model sloshing impact in roofed tanks. It is incorporated into Argonne`s in-house finite element code FLUSTR-ANL. A numerical test case with a harmonic input excitation is studied. The simulation results indicate that linear behavior is preserved beyond the first impact, and some mesh distortion is observed following a stronger second impact. During the impact, the displacement of the contacting surface nodes remains constant, and the velocities are reduced to zero. An identification of impacting nodes is possible from the dynamic pressures induced in surface elements.

  20. Thermal Performance of Vegetative Roofing Systems

    SciTech Connect

    Desjarlais, Andre Omer; Zaltash, Abdolreza; Atchley, Jerald Allen; Ennis, Mike J

    2010-01-01

    Vegetative roofing, otherwise known as green or garden roofing, has seen tremendous growth in the last decade in the United States. The numerous benefits that green roofs provide have helped to fuel their resurgence in industrial and urban settings. There are many environmental and economical benefits that can be realized by incorporating a vegetative roof into the design of a building. These include storm-water retention, energy conservation, reduction in the urban heat island effect, increased longevity of the roofing membrane, the ability of plants to create biodiversity and filter air contaminants, and beautification of the surroundings by incorporating green space. The vegetative roof research project at Oak Ridge National Laboratory (ORNL) was initiated to quantify the thermal performance of various vegetative roofing systems relative to black and white roofs. Single Ply Roofing Institute (SPRI) continued its long-term commitment to cooperative research with ORNL in this project. Low-slope roof systems for this study were constructed and instrumented for continuous monitoring in the mixed climate of East Tennessee. This report summarizes the results of the annual cooling and heating loads per unit area of three vegetative roofing systems with side-by-side comparison to black and white roofing systems as well as a test section with just the growing media without plants. Results showed vegetative roofs reduced heat gain (reduced cooling loads) compared to the white control system due to the thermal mass, extra insulation, and evapo-transpiration associated with the vegetative roofing systems. The 4-inch and tray systems reduced the heat gain by approximately 61%, while the reduction with the 8-inch vegetative roof was found to be approximately 67%. The vegetative roofing systems were more effective in reducing heat gain than in reducing heat losses (heating loads). The reduction in heat losses for the 4-inch and tray systems were found to be approximately 40% in the mixed climate of East Tennessee. It should be noted that these values are climate dependent. Vegetative roofs also reduced the temperature (heat exposure) and temperature fluctuations (thermal stress) experienced by the membrane. In the cooling season of East Tennessee, the average peak temperature of the 4-inch and tray systems was found to be approximately 94 F cooler than the control black roofing system. The average temperature fluctuations at the membrane for the 4-inch and tray systems were found to be approximately 10 F compared to 125 F for black and 64 F for white systems. As expected, the 8-inch vegetative roof had the lowest fluctuations at approximately 2 F. Future work will include modeling of the energy performance of vegetative roof panels in the test climate of East Tennessee. The validated model then will be used to predict energy use in roofs with different insulation levels and in climates different from the test climate.

  1. High Performance Ultrathin GaAs Solar Cells Enabled with Heterogeneously Integrated Dielectric Periodic Nanostructures.

    PubMed

    Lee, Sung-Min; Kwong, Anthony; Jung, Daehwan; Faucher, Joseph; Biswas, Roshni; Shen, Lang; Kang, Dongseok; Lee, Minjoo Larry; Yoon, Jongseung

    2015-10-27

    Due to their favorable materials properties including direct bandgap and high electron mobilities, epitaxially grown III-V compound semiconductors such as gallium arsenide (GaAs) provide unmatched performance over silicon in solar energy harvesting. Nonetheless, their large-scale deployment in terrestrial photovoltaics remains challenging mainly due to the high cost of growing device quality epitaxial materials. In this regard, reducing the thickness of constituent active materials under appropriate light management schemes is a conceptually viable option to lower the cost of GaAs solar cells. Here, we present a type of high efficiency, ultrathin GaAs solar cell that incorporates bifacial photon management enabled by techniques of transfer printing to maximize the absorption and photovoltaic performance without compromising the optimized electronic configuration of planar devices. Nanoimprint lithography and dry etching of titanium dioxide (TiO2) deposited directly on the window layer of GaAs solar cells formed hexagonal arrays of nanoscale posts that serve as lossless photonic nanostructures for antireflection, diffraction, and light trapping in conjunction with a co-integrated rear-surface reflector. Systematic studies on optical and electrical properties and photovoltaic performance in experiments, as well as numerical modeling, quantitatively describe the optimal design rules for ultrathin, nanostructured GaAs solar cells and their integrated modules. PMID:26376087

  2. Study of water infiltration in a lightweight green roof substrate

    NASA Astrophysics Data System (ADS)

    Tomankova, Klara; Holeckova, Martina; Jelinkova, Vladimira; Snehota, Michal

    2015-04-01

    Green roofs have a positive impact on the environment (e.g. improving microclimate and air quality in cities, reducing solar absorbance and storm water). A laboratory infiltration experiment was conducted on the narrow flume serving as 2D vertical model of a green roof. The lightweight Optigreen substrate Type M was used (depth of 20 cm). The front wall of the flume was transparent and inspected by digital camera. The experiment was designed to measure pressure head, volumetric water content and calculate water retention in the substrate. Experiment comprised three artificial rainfall intensities with different values of initial water content of the substrate. The experimental results confirmed that green roofs have the ability to retain rainwater and thus have a beneficial effect on reducing runoff. In the experiment with the artificial 10 minutes rainfall event (total precipitation of 29 mm), the air dry substrate retained 95.9 % of precipitation. On the other hand for moist initial condition 4.2 % of precipitations amount was captured in the substrate. Additionally, the analysis of images taken during the experiment confirmed preferential flow and uneven advancement of the wetting front. The research was realized as a part of the University Centre for Energy Efficient Buildings supported by the EU and with financial support from the Czech Science Foundation under project number 14-10455P.

  3. Interpretation of 2d and 3d Building Details on Facades and Roofs

    NASA Astrophysics Data System (ADS)

    Meixner, P.; Leberl, F.; Brédif, M.

    2011-04-01

    Current Internet-inspired mapping data are in the form of street maps, orthophotos, 3D models or street-side images and serve to support mostly search and navigation. Yet the only mapping data that currently can really be searched are the street maps via their addresses and coordinates. The orthophotos, 3D models and street-side images represent predominantly "eye candy" with little added value to the Internet-user. We are interested in characterizing the elements of the urban space from imagery. In this paper we discuss the use of street side imagery and aerial imagery to develop descriptions of urban spaces, initially of building facades and roofs. We present methods (a) to segment facades using high-overlap street side facade images, (b) to map facades and facade details from vertical aerial images, and (c) to characterize roofs by their type and details, also from aerial photography. This paper describes a method of roof segmentation with the goal of assigning each roof to a specific architectural style. Questions of the use of the attic space, or the placement of solar panels, are of interest. It is of interest that roofs have recently been mapped using LiDAR point clouds. We demonstrate that aerial images are a useful and economical alternative to LiDAR for the characterization of building roofs, and that they also contain very valuable information about facades.

  4. OPTIMIZING GREEN ROOF TECHNOLOGIES IN THE MIDWEST

    EPA Science Inventory

    Green roofs, while extensively used in Europe, are an emerging technology in the U.S. They have an array of potential benefits (including improved storm water management, increased energy conservation of buildings, reduced urban heat island effects, and extended roof life) ...

  5. Roofs--Their Problems and Solutions.

    ERIC Educational Resources Information Center

    Swentkofske, Carl J.

    Most roofs are meant to withstand the elements for a period of 20 years; to achieve this goal, however, school officials must believe in a dedicated maintenance program and sell it to their superiors and school boards. Establishment of a school district roof maintenance program is explained. Job qualifications and training methods for an inhouse…

  6. Metal Roofing in a "Class" by Itself.

    ERIC Educational Resources Information Center

    Nimtz, Paul D.

    1990-01-01

    The structural standing seam roof has the advantages of ease of application, low maintenance, and low life-cycle costs. Explains and illustrates how the system's concealed clip attachments are designed so that the roof panels can expand and contract independently of the insulation. (MLF)

  7. Roofing Workbook and Tests. Plans and Specifications.

    ERIC Educational Resources Information Center

    Mongerson, M. Duane, Comp.

    This combination workbook and set of tests on plans and specifications is one in a series of nine individually bound units of instruction for roofing apprenticeship classes. The five topics covered are (1) regulations governing the roofing and waterproofing industry, (2) an overview of blueprints, (3) an overview of specifications, (4)…

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

    SciTech Connect

    Syd S. Peng

    2002-01-15

    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. A new mechanical approach to estimate rock strengths using the acquired drilling parameters has been proposed. This approach takes a number of important factors, that have never been studied in the previous researches, into the considerations. Good results have been shown using the new approach on the testing data.

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

    SciTech Connect

    Syd S. Peng

    2002-04-15

    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 laboratory tests have been performed in this quarter. The analysis performed on the testing data showed: (1) abnormal rotational accelerations can be used as the indicator of the rock interfaces, and (2) the sharp drops of drilling thrust and torque agree well with the locations of fractures.

  10. Development of an integrated heat pipe-thermal storage system for a solar receiver

    NASA Astrophysics Data System (ADS)

    Keddy, E.; Sena, J. Tom; Merrigan, M.; Heidenreich, Gary; Johnson, Steve

    1988-06-01

    An integrated heat pipe-thermal storage system was developed as part of the Organic Rankine Cycle Solar Dynamic Power System solar receiver for space station application. The solar receiver incorporates potassium heat pipe elements to absorb and transfer the solar energy within the receiver cavity. The heat pipes contain thermal energy storage (TES) canisters within the vapor space with a toluene heater tube used as the condenser region of the heat pipe. During the insolation period of the earth orbit, solar energy is delivered to the heat pipe. Part of this thermal energy is delivered to the heater tube and the balance is stored in the TES units. During the eclipse period of earth orbit, the stored energy in the TES units is transferred by the potassium vapor to the toluene heater tube. A developmental heat pipe element was constructed that contains axial arteries and a distribution wick connecting the toluene heater and the TES units to the solar insolation surface of the heat pipe. Tests were conducted to demonstrate the heat pipe, TES units, and the heater tube operation. The heat pipe element was operated at design input power of 4.8 kW. Thermal cycle tests were conducted to demonstrate the successful charge and discharge of the TES units. Axial power flux levels up to 15 watts/sq cm were demonstrated and transient tests were conducted on the heat pipe element. Details of the heat pipe development and test procedures are presented.

  11. Development of an integrated heat pipe-thermal storage system for a solar receiver

    NASA Technical Reports Server (NTRS)

    Keddy, E.; Sena, J. Tom; Merrigan, M.; Heidenreich, Gary; Johnson, Steve

    1988-01-01

    An integrated heat pipe-thermal storage system was developed as part of the Organic Rankine Cycle Solar Dynamic Power System solar receiver for space station application. The solar receiver incorporates potassium heat pipe elements to absorb and transfer the solar energy within the receiver cavity. The heat pipes contain thermal energy storage (TES) canisters within the vapor space with a toluene heater tube used as the condenser region of the heat pipe. During the insolation period of the earth orbit, solar energy is delivered to the heat pipe. Part of this thermal energy is delivered to the heater tube and the balance is stored in the TES units. During the eclipse period of earth orbit, the stored energy in the TES units is transferred by the potassium vapor to the toluene heater tube. A developmental heat pipe element was constructed that contains axial arteries and a distribution wick connecting the toluene heater and the TES units to the solar insolation surface of the heat pipe. Tests were conducted to demonstrate the heat pipe, TES units, and the heater tube operation. The heat pipe element was operated at design input power of 4.8 kW. Thermal cycle tests were conducted to demonstrate the successful charge and discharge of the TES units. Axial power flux levels up to 15 watts/sq cm were demonstrated and transient tests were conducted on the heat pipe element. Details of the heat pipe development and test procedures are presented.

  12. Assessment of the hydrological impacts of green roof: From building scale to basin scale

    NASA Astrophysics Data System (ADS)

    Versini, P.-A.; Ramier, D.; Berthier, E.; de Gouvello, B.

    2015-05-01

    At the building scale, the use of green roof has shown a positive impact on urban runoff (decrease and slow-down in peak discharge, decrease in runoff volume). The present work aims to study whether similar effects are possible at the basin scale and what is the minimum spreading of green runoff needed to observe significant impacts. It is particularly focused on the circumstances of such impacts and how they can contribute to storm water management in urban environment. Based on observations on experimental green roofs, a conceptual model has been developed and integrated into the SWMM urban rainfall-runoff model to reproduce the hydrological behaviour of two different types of green roof. It has been combined with a method defining green roofing scenarios by estimating the maximum roof area that can be covered. This methodology has been applied on a long time series (18 years) to the Châtillon urban basin (Haut-de-Seine county, France) frequently affected by urban flooding. For comparison, the same methodology has been applied at the building scale and a complementary analysis has been conducted to study which hydrometeorological variables may affect the magnitude of these hydrological impacts at both scales. The results show green roofs, when they are widely implemented, can affect urban runoff in terms of peak discharge and volume, and avoid flooding in several cases. Both precipitation - generally accumulated during the whole event- and the initial substrate saturation are likely to have an impact on green roof effects. In this context, the studied green roofs seem useful to mitigate the effects of usual rainfall events but turn out being less helpful for the more severe ones. We conclude that, combined with other infrastructures, green roofs represent an interesting contribution to urban water management in the future.

  13. Method for fabricating solar cells having integrated collector grids

    NASA Technical Reports Server (NTRS)

    Evans, J. C., Jr. (Inventor)

    1979-01-01

    A heterojunction or Schottky barrier photovoltaic device comprising a conductive base metal layer compatible with and coating predominately the exposed surface of the p-type substrate of the device such that a back surface field region is formed at the interface between the device and the base metal layer, a transparent, conductive mixed metal oxide layer in integral contact with the n-type layer of the heterojunction or Schottky barrier device having a metal alloy grid network of the same metal elements of the oxide constituents of the mixed metal oxide layer embedded in the mixed metal oxide layer, an insulating layer which prevents electrical contact between the conductive metal base layer and the transparent, conductive metal oxide layer, and a metal contact means covering the insulating layer and in intimate contact with the metal grid network embedded in the transparent, conductive oxide layer for conducting electrons generated by the photovoltaic process from the device.

  14. Solar astronomy

    NASA Technical Reports Server (NTRS)

    Rosner, Robert; Noyes, Robert; Antiochos, Spiro K.; Canfield, Richard C.; Chupp, Edward L.; Deming, Drake; Doschek, George A.; Dulk, George A.; Foukal, Peter V.; Gilliland, Ronald L.

    1991-01-01

    An overview is given of modern solar physics. Topics covered include the solar interior, the solar surface, the solar atmosphere, the Large Earth-based Solar Telescope (LEST), the Orbiting Solar Laboratory, the High Energy Solar Physics mission, the Space Exploration Initiative, solar-terrestrial physics, and adaptive optics. Policy and related programmatic recommendations are given for university research and education, facilitating solar research, and integrated support for solar research.

  15. Increasing roof bolter operator awareness to risks of falling roof material during the bolting cycle

    SciTech Connect

    Klishis, M.J.; Althouse, R.C.; Lies, G.M. ); Layne, L.A. )

    1993-01-01

    The reduction of injuries due to falls of roof material is a longtime concern of the mining industry. Bolter operators are continually exposed to rib and roof falls as they perform their normal work tasks. Massive roof falls rather than the typical small falls have been the traditional focus of mine safety practitioners. However, falls of smaller amounts of roof material are a common source of injuries to roof bolter operators and other miners who perform roof-bolting work. This paper presents the findings of a study on roof bolter operators' exposure to falls of roof material. The results are important to the development of safer work practices for all underground miners who are assigned to roof-bolting tasks and related roof support activities. A detailed microanalysis of accident data was combined with worksite observations of bolting activities. Specific tasks associated with injuries as well as the causes of roof fall injuries were identified and organized according to four work routines: (1) preparing the work place, (2) tramming and positioning equipment, (3) drilling, and (4) bolting. The lack of detail on injury reports hindered the analysis of hazards that may lead to injuries among all bolters. A roof bolter observation checklist was developed to be used by safety personnel, trainers, and supervisors. In addition, the results of lost-time injuries found in the accident reports were combined with time studies of roof bolter operators to develop a set of risk and severity-weighted indices. An analysis of the four roof-bolting work routines revealed several safety problems and led to a series of recommendations for improving operator safety.

  16. Cooler Tile-Roofed Buildings with Near-Infrared-ReflectiveNon-white Coatings

    SciTech Connect

    Levinson, Ronnen; Akbari, Hashem; Reilly, Joeseph C.

    2004-06-25

    Owners of homes with pitched roofs visible from ground leveloften prefer non-white roofing products for aesthetic considerations.Non-white, near-infrared-reflective architectural coatings can be appliedin-situ to pitched concrete or clay tile roofs to reduce tiletemperature, building heat gain, and cooling power demand, whilesimultaneously improving the roof s appearance. Scale model measurementsof building temperatures and heat-flux were combined with solar andcooling energy use data to estimate the effects of such cool roofcoatings in various California data. Under typical conditions e.g., 1 kWm-2 summer afternoon insolation, R-11 attic insulation, no radiantbarrier, and a 0.3 reduction in solar absorptance absolute reductions inroof surface temperature, attic air temperature, and ceiling heat fluxare about 12 K, 6.2 K, and 3.7 W m-2, respectively. For a typical 1,500ft2 (139 m2) house with R-11 attic insulation and no radiant barrier,reducing roof absorptance by 0.3 yields whole-house peak power savings of230, 210, and 210 W in Fresno, San Bernardino, and San Diego,respectively. The corresponding absolute and fractional cooling energysavings are 92 kWh yr-1 (5 percent), 67 kWh yr-1 (6 percent), and 8 kWhyr-1 (1 percent), respectively. These savings are about half thosepreviously reported for houses with non-tile roofs. With theseassumptions, the statewide peak cooling power and annual cooling energyreductions would be 240 MW and 63 GWh yr-1, respectively. These energysavings would reduce annual emissions from California power plants by 35kilotonnes CO2, 11 tonnes NOx,and 0.86 tonnes SOx. The economic value ofcooling energy savings is well below the cost of coating a tile roof, butthe simple payback times for using cool pigments in a rooftile coatingare modest (5-7 years) in the hot climates of Fresno and SanBernardino.

  17. Solar Spots - Activities to Introduce Solar Energy into the K-8 Curricula.

    ERIC Educational Resources Information Center

    Longe, Karen M.; McClelland, Michael J.

    Following an introduction to solar technology which reviews solar heating and cooling, passive solar systems (direct gain systems, thermal storage walls, sun spaces, roof ponds, and convection loops), active solar systems, solar electricity (photovoltaic and solar thermal conversion systems), wind energy, and biomass, activities to introduce solar…

  18. Integrated Phase Array Antenna/Solar Cell System for Flexible Access Communication (IA/SAC)

    NASA Technical Reports Server (NTRS)

    Clark, E. B.; Lee, R. Q.; Pal, A. T.; Wilt, D. M.; McElroy, B. D.; Mueller, C. H.

    2005-01-01

    This paper describes recent efforts to integrate advanced solar cells with printed planar antennas. Several previous attempts have been reported in the literature, but this effort is unique in several ways. It uses Gallium Arsenide (GaAs) multi-junction solar cell technology. The solar cells and antennas will be integrated onto a common GaAs substrate. When fully implemented, IA/SAC will be capable of dynamic beam steering. In addition, this program targets the X-band (8 - 12 GHz) and higher frequencies, as compared to the 2.2 - 2.9 GHz arrays targeted by other organizations. These higher operating frequencies enable a greater bandwidth and thus higher data transfer rates. The first phase of the effort involves the development of 2 x 2 cm GaAs Monolithically Integrated Modules (MIM) with integrated patch antennas on the opposite side of the substrate. Subsequent work will involve the design and development of devices having the GaAs MIMs and the antennas on the same side of the substrate. Results from the phase one efforts will be presented.

  19. Integrating Solar PV in Utility System Operations: Analytical Framework and Arizona Case Study

    SciTech Connect

    Wu, Jing; Botterud, Audun; Mills, Andrew; Zhou, Zhi; Hodge, Bri-Mathias; Mike, Heaney

    2015-06-01

    A systematic framework is proposed to estimate the impact on operating costs due to uncertainty and variability in renewable resources. The framework quantifies the integration costs associated with subhourly variability and uncertainty as well as day-ahead forecasting errors in solar PV (photovoltaics) power. A case study illustrates how changes in system operations may affect these costs for a utility in the southwestern United States (Arizona Public Service Company). We conduct an extensive sensitivity analysis under different assumptions about balancing reserves, system flexibility, fuel prices, and forecasting errors. We find that high solar PV penetrations may lead to operational challenges, particularly during low-load and high solar periods. Increased system flexibility is essential for minimizing integration costs and maintaining reliability. In a set of sensitivity cases where such flexibility is provided, in part, by flexible operations of nuclear power plants, the estimated integration costs vary between $1.0 and $4.4/MWh-PV for a PV penetration level of 17%. The integration costs are primarily due to higher needs for hour-ahead balancing reserves to address the increased sub-hourly variability and uncertainty in the PV resource. (C) 2015 Elsevier Ltd. All rights reserved.

  20. Solar Energy Grid Integration Systems -- Energy Storage (SEGIS-ES).

    SciTech Connect

    Hanley, Charles J.; Ton, Dan T.; Boyes, John D.; Peek, Georgianne Huff

    2008-07-01

    This paper describes the concept for augmenting the SEGIS Program (an industry-led effort to greatly enhance the utility of distributed PV systems) with energy storage in residential and small commercial applications (SEGIS-ES). The goal of SEGIS-ES is to develop electrical energy storage components and systems specifically designed and optimized for grid-tied PV applications. This report describes the scope of the proposed SEGIS-ES Program and why it will be necessary to integrate energy storage with PV systems as PV-generated energy becomes more prevalent on the nation's utility grid. It also discusses the applications for which energy storage is most suited and for which it will provide the greatest economic and operational benefits to customers and utilities. Included is a detailed summary of the various storage technologies available, comparisons of their relative costs and development status, and a summary of key R&D needs for PV-storage systems. The report concludes with highlights of areas where further PV-specific R&D is needed and offers recommendations about how to proceed with their development.

  1. Sheet-flow concrete solar collector

    SciTech Connect

    Naccache, A.F.

    1983-04-05

    An open-flow concrete flat-plate solar collector has a grooved photothermal conversion surface coated with an impermeable selective coating of high capillarity. A special header insures spreading of the heat transfer fluid over the photothermal conversion surface even if the collector is not perfectly level. The collector is used in a closed loop heat exchanger system or a closed loop thermosiphoning system with, as a heat transfer fluid , distilled water to which is added an antistatic agent. The collector may be free-standing, or it can be added onto an existing inclined roof, or incorporated as an integral part of such roof. This collector preferably is used for applications up to 150* F.

  2. Integrated three-dimensional photonic nanostructures for achieving near-unity solar absorption and superhydrophobicity

    NASA Astrophysics Data System (ADS)

    Kuang, Ping; Hsieh, Mei-Li; Lin, Shawn-Yu

    2015-06-01

    In this paper, we proposed and realized 3D photonic nanostructures consisting of ultra-thin graded index antireflective coatings (ARCs) and woodpile photonic crystals. The use of the integrated ARC and photonic crystal structure can achieve broadband, broad-angle near unity solar absorption. The amorphous silicon based photonic nanostructure experimentally shows an average absorption of ˜95% for λ = 400-620 nm over a wide angular acceptance of θ = 0°-60°. Theoretical studies show that a Gallium Arsenide (GaAs) based structure can achieve an average absorption of >95% for λ = 400-870 nm. Furthermore, the use of the slanted SiO2 nanorod ARC surface layer by glancing angle deposition exhibits Cassie-Baxter state wetting, and superhydrophobic surface is obtained with highest water contact angle θCB ˜ 153°. These properties are fundamentally important for achieving maximum solar absorption and surface self-cleaning in thin film solar cell applications.

  3. Experiments and simulations on a thermosyphon solar collector with integrated storage

    NASA Astrophysics Data System (ADS)

    Toninelli, P.; Mariani, A.; Del, D., Col

    2015-11-01

    This paper deals with the thermal behaviour of a new type of flat solar collector that integrates the fluid storage tank. Often the main limitation of the solar thermosyphon installations is the prohibition to adopt external storage tanks due to their impact, especially for historical centres of particular architectural significance. To avoid this issue, a new system, that includes the collector and the storage, has been developed. This new apparatus works as a thermosyphon: it is possible to take advantage of the natural convection to avoid using a pump. Experimental tests have been conducted in such a collector with and without the absorbing plate. Furthermore, CFD simulations are reported to analyze in detail the dynamic thermal performance of the innovative solar collector and a good-agreement with the experimental tests has been found. Finally, both in numerical simulations and in experimental data the thermosyphon effect has been verified, obtaining the desired water temperature for domestic applications.

  4. Solar cell shingle

    NASA Technical Reports Server (NTRS)

    Forestieri, A. F.; Ratajczak, A. F.; Sidorak, L. G. (Inventor)

    1977-01-01

    A solar cell shingle was made of an array of solar cells on a lower portion of a substantially rectangular shingle substrate made of fiberglass cloth or the like. The solar cells may be encapsulated in flourinated ethylene propylene or some other weatherproof translucent or transparent encapsulant to form a combined electrical module and a roof shingle. The interconnected solar cells were connected to connectors at the edge of the substrate through a connection to a common electrical bus or busses. An overlap area was arranged to receive the overlap of a cooperating similar shingle so that the cell portion of the cooperating shingle may overlie the overlap area of the roof shingle. Accordingly, the same shingle serves the double function of an ordinary roof shingle which may be applied in the usual way and an array of cooperating solar cells from which electrical energy may be collected.

  5. Western Wind and Solar Integration Study Phase 3A: Low Levels of Synchronous Generation

    SciTech Connect

    Miller, Nicholas W.; Leonardi, Bruno; D'Aquila, Robert; Clark, Kara

    2015-11-17

    The stability of the North American electric power grids under conditions of high penetrations of wind and solar is a significant concern and possible impediment to reaching renewable energy goals. The 33% wind and solar annual energy penetration considered in this study results in substantial changes to the characteristics of the bulk power system. This includes different power flow patterns, different commitment and dispatch of existing synchronous generation, and different dynamic behavior from wind and solar generation. The Western Wind and Solar Integration Study (WWSIS), sponsored by the U.S. Department of Energy, is one of the largest regional solar and wind integration studies to date. In multiple phases, it has explored different aspects of the question: Can we integrate large amounts of wind and solar energy into the electric power system of the West? The work reported here focused on the impact of low levels of synchronous generation on the transient stability performance in one part of the region in which wind generation has displaced synchronous thermal generation under highly stressed, weak system conditions. It is essentially an extension of WWSIS-3. Transient stability, the ability of the power system to maintain synchronism among all elements following disturbances, is a major constraint on operations in many grids, including the western U.S. and Texas systems. These constraints primarily concern the performance of the large-scale bulk power system. But grid-wide stability concerns with high penetrations of wind and solar are still not thoroughly understood. This work focuses on 'traditional' fundamental frequency stability issues, such as maintaining synchronism, frequency, and voltage. The objectives of this study are to better understand the implications of low levels of synchronous generation and a weak grid on overall system performance by: 1) Investigating the Western Interconnection under conditions of both high renewable generation (e.g., wind and solar) and low synchronous generation (e.g., significant coal power plant decommitment or retirement); and 2) Analyzing both the large-scale stability of the Western Interconnection and regional stability issues driven by more geographically dispersed renewable generation interacting with a transmission grid that evolved with large, central station plants at key nodes. As noted above, the work reported here is an extension of the research performed in WWSIS-3.

  6. Building-Integrated Solar Energy Devices based on Wavelength Selective Films

    NASA Astrophysics Data System (ADS)

    Ulavi, Tejas

    A potentially attractive option for building integrated solar is to employ hybrid solar collectors which serve dual purposes, combining solar thermal technology with either thin film photovoltaics or daylighting. In this study, two hybrid concepts, a hybrid photovoltaic/thermal (PV/T) collector and a hybrid 'solar window', are presented and analyzed to evaluate technical performance. In both concepts, a wavelength selective film is coupled with a compound parabolic concentrator (CPC) to reflect and concentrate the infrared portion of the solar spectrum onto a tubular absorber. The visible portion of the spectrum is transmitted through the concentrator to either a thin film Cadmium Telluride (CdTe) solar panel for electricity generation or into the interior space for daylighting. Special attention is given to the design of the hybrid devices for aesthetic building integration. An adaptive concentrator design based on asymmetrical truncation of CPCs is presented for the hybrid solar window concept. The energetic and spectral split between the solar thermal module and the PV or daylighting module are functions of the optical properties of the wavelength selective film and the concentrator geometry, and are determined using a Monte Carlo Ray-Tracing (MCRT) model. Results obtained from the MCRT can be used in conjugation with meteorological data for specific applications to study the impact of CPC design parameters including the half-acceptance angle thetac, absorber diameter D and truncation on the annual thermal and PV/daylighting efficiencies. The hybrid PV/T system is analyzed for a rooftop application in Phoenix, AZ. Compared to a system of the same area with independent solar thermal and PV modules, the hybrid PV/T provides 20% more energy, annually. However, the increase in total delivered energy is due solely to the addition of the thermal module and is achieved at an expense of a decrease in the annual electrical efficiency from 8.8% to 5.8% due to shading by the absorber tubes. For this reason, the PV/T hybrid is not recommended over other options in new installations. The hybrid solar window is evaluated for a horizontal skylight and south and east facing vertical windows in Minneapolis, MN. The predicted visible transmittance for the solar window is 0.66 to 0.73 for single glazed systems and 0.61 to 0.67 for double glazed systems. The solar heat gain coefficient and the U-factor for the window are comparable to existing glazing technology. Annual thermal efficiencies of up to 24% and 26% are predicted for the vertical window and the horizontal skylight respectively. Experimental measurements of the solar thermal component of the window confirm the trends of the model. In conclusion, the hybrid solar window combines the functionality of an energy efficient fenestration system with hybrid thermal energy generation to provide a compelling solution towards sustainable design of the built environment.

  7. Use of treated woods in roof assembly.

    PubMed

    Edlich, Richard F; Winters, Kathryne L; Long, William B; Gubler, K Dean; Britt, L D

    2005-01-01

    On February 12, 2002, the US Environmental Protection Agency (EPA) announced a voluntary decision by industry to move consumer use of treated lumber products away from a variety of pressure-treated wood that contains Arsenate (As) by December 31, 2003, in favor of new alternative wood preservatives. It is the purpose of this report to outline legislative efforts to ban the use of chromated copper arsenate (CCA)-treated wood for residential roofing in the State of Oregon. At the time that the legislation was introduced, it was coincidental that the National Roofing Contractors Association (NRCA) recommended that CCA-treated wood should not be used in residential roofing. A summary of the report is included in this review. Finally, we discuss some of the potentially harmful environmental hazards of wood preservatives on the environment. In addition to the toxicity of pressure-treated wood on our environment, we point out that wood as well as pressure-treated wood assemblies are highly flammable. Consequently, we recommend the use of residential roofing systems that have Class A fire protection for the homeowner. Because residential roof fires remain a life-threatening danger to residential homeowners in the United States, we describe a national fire prevention program for reducing residential roof fires by use of an Underwriters Laboratories Inc. (UL) and National Fire Protection Association Class A fire-rated roof system. PMID:16022647

  8. Decision Guide for Roof Slope Selection

    SciTech Connect

    Sharp, T.R.

    1988-01-01

    This decision guide has been written for personnel who are responsible for the design, construction, and replacement of Air Force roofs. It provides the necessary information and analytical tools for making prudent and cost-effective decisions regarding the amount of slope to provide in various roofing situations. Because the expertise and experience of the decision makers will vary, the guide contains both basic slope-related concepts as well as more sophisticated technical data. This breadth of information enables the less experienced user to develop an understanding of roof slope issues before applying the more sophisticated analytical tools, while the experienced user can proceed directly to the technical sections. Although much of this guide is devoted to the analysis of costs, it is not a cost-estimating document. It does, however, provide the reader with the relative costs of a variety of roof slope options; and it shows how to determine the relative cost-effectiveness of different options. The selection of the proper roof slope coupled with good roof design, a quality installation, periodic inspection, and appropriate maintenance and repair will achieve the Air Force's objective of obtaining the best possible roofing value for its buildings.

  9. Development of an integrated heat pipe-thermal storage system for a solar receiver

    SciTech Connect

    Keddy, E.S.; Sena, J.T.; Merrigan, M.A.; Heidenreich, G.; Johnson, S.

    1987-01-01

    The Organic Rankine Cycle (ORC) Solar Dynamic Power System (SDPS) is one of the candidates for Space Station prime power application. In the low earth orbit of the Space Station approximately 34 minutes of the 94-minute orbital period is spent in eclipse with no solar energy input to the power system. For this period the SDPS will use thermal energy storage (TES) material to provide a constant power output. Sundstrand Corporation is developing a ORC-SDPS candidate for the Space Station that uses toluene as the organic fluid and LiOH as the TES material. An integrated heat-pipe thermal storage receiver system is being developed as part of the ORC-SDPS solar receiver. This system incorporates potassium heat pipe elements to absorb and transfer the solar energy within the receiver cavity. The heat pipes contain the TES canisters within the potassium vapor space with the toluene heater tube used as the condenser region of the heat pipe. During the insolation period of the earth orbit, solar energy is delivered to the heat pipe in the ORC-SDPS receiver cavity. The heat pipe transforms the non-uniform solar flux incident in the heat pipe surface within the receiver cavity to an essentially uniform flux at the potassium vapor condensation interface in the heat pipe. During solar insolation, part of the thermal energy is delivered to the heater tube and the balance is stored in the TES units. During the eclipse period of the orbit, the balance stored in the TES units is transferred by the potassium vapor to the toluene heater tube. 3 refs., 8 figs.

  10. Integration Costs: Are They Unique to Wind and Solar Energy? Preprint

    SciTech Connect

    Milligan, M.; Hodge, B.; Kirby, B.; Clark, C.

    2012-05-01

    Over the past several years, there has been considerable interest in assessing wind integration costs. This is understandable because wind energy does increase the variability and uncertainty that must be managed on a power system. However, there are other sources of variability and uncertainty that also must be managed in the power system. This paper describes some of these sources and shows that even the introduction of base-load generation can cause additional ramping and cycling. The paper concludes by demonstrating that integration costs are not unique to wind and solar, and should perhaps instead be assessed by power plant and load performance instead of technology type.

  11. NREL Confirms Large Potential for Grid Integration of Wind, Solar Power (Fact Sheet)

    SciTech Connect

    Not Available

    2011-10-01

    To fully harvest the nation's bountiful wind and solar resources, it is critical to know how much electrical power from these renewable resources could be integrated reliably into the grid. To inform the discussion about the potential of such variable sources, the National Renewable Energy Laboratory (NREL) launched two key regional studies, examining the east and west sections of the U.S. power grid. The studies show that it is technically possible for U.S. power systems to integrate 20%-35% renewable electricity if infrastructure and operational improvements can be made.

  12. Integral glass encapsulation for solar arrays. Quarterly progress report No. 14

    SciTech Connect

    1980-08-01

    This is the fourteenth quarterly report under a JPL/DOE program to develop electrostatic bonding as a method of integral encapsulation of solar cells in glass. Efforts for the current phase of this program are to continue demonstrations of process uniformity of electrostatic bonding encapsulation by production of 24-cell minimodules by ESB. Additional goals of this program are to develop preformed (wire-mesh) contacts as a method of integrating cell processing into the encapsulation procedure, resulting in a low-cost module assembly technique, and to investigate low-temperature bonding to commercially available glass (Pyrex) superstrates. Progress is reported.

  13. Solar energy assessment in the Alpine area: satellite data and ground instruments integration for studying the radiative forcing of aerosols.

    NASA Astrophysics Data System (ADS)

    Castelli, M.; Petitta, M.; Emili, E.

    2012-04-01

    The primary objective of this work is to purpose an approach for estimating the effect of aerosols on surface incoming shortwave radiation (SIS) in the Alpine region, which is based on the integration of different instruments: we develop a GIS model, whose output is corrected by monthly atmospheric coefficients, and then we progressively add details by daily updated atmospheric information. The assessment of solar energy availability at the earth's surface over a specific geographic area is crucial for planning photovoltaic panels installation. When modeling SIS with GIS instruments or retrieving it from satellites measurements, we have to account for terrain shadowing and atmospheric extinction, both of which are difficult to describe in the Alpine area, because of the topographic complexity and the local atmospheric circulation influence on the atmospheric composition. While advanced methods were developed to carefully describe the effect of topography, the atmospheric attenuation was considered so far only through monthly turbidity values, and the question remains whether it be possible to develop a time-effective routine to model the atmospheric effect on SIS at daily scale. As a first step we produced a WebGIS for the town of Bressanone, Italy, showing a classification of the roofs of the buildings according to the yearly amount of global irradiance. Furthermore we provide the annual electricity production based on the efficiency of the most common PV technologies. At this stage clear sky irradiance was computed with a GIS based model, and afterwards monthly correction coefficients were applied to add real sky conditions to the merely geometrical computations, which were obtained from 20 years of measurement collected by the pyranometer in the closest meteorological station. As a second step we investigate the influence of aerosol optical properties on SIS by running the radiative transfer model libRadtran by using as input the aerosol model defined for the measurement site of Bolzano, where we installed an AERONET sun-photometer for measuring aerosol optical properties and column water-vapor amount. The impact of aerosols on the surface irradiance was already demonstrated, in fact the literature shows that the daily aerosol direct forcing on the surface radiation in the Italian Po valley amounts on average to -12.2 Wm-2, with extremes values beyond -70 Wm-2. In particular here we examine the role in the radiation budget of the Alpine valleys of aerosol microphysical characteristics, such as size distribution, and optical properties, such as phase function, derived from the inversion of spectrally resolved sky radiances. After provided evidence of the radiative impact of atmospheric aerosols on solar energy availability in the Alpine area, the final step will be the enhancement of the most advanced existent algorithm for retrieving SIS in the Alpine area from satellite data, developed by MeteoSwiss in the framework of CM-SAF, which thoroughly considers the effect of topography and clouds, while can still be improved in terms of atmospheric input data.

  14. 30 CFR 75.206 - Conventional roof support.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Conventional roof support. 75.206 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.206 Conventional roof support. (a) Except in anthracite mines using non-mechanized mining systems, when conventional roof...

  15. 30 CFR 75.206 - Conventional roof support.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Conventional roof support. 75.206 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.206 Conventional roof support. (a) Except in anthracite mines using non-mechanized mining systems, when conventional roof...

  16. 30 CFR 75.206 - Conventional roof support.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Conventional roof support. 75.206 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.206 Conventional roof support. (a) Except in anthracite mines using non-mechanized mining systems, when conventional roof...

  17. 30 CFR 75.206 - Conventional roof support.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Conventional roof support. 75.206 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.206 Conventional roof support. (a) Except in anthracite mines using non-mechanized mining systems, when conventional roof...

  18. 30 CFR 75.206 - Conventional roof support.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Conventional roof support. 75.206 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.206 Conventional roof support. (a) Except in anthracite mines using non-mechanized mining systems, when conventional roof...

  19. 24 CFR 3280.402 - Test procedure for roof trusses.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 5 2012-04-01 2012-04-01 false Test procedure for roof trusses... procedure for roof trusses. (a) Roof load tests. The following is an acceptable test procedure, consistent with the provisions of § 3280.401, for roof trusses that are supported at the ends and support...

  20. 24 CFR 3280.402 - Test procedure for roof trusses.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 5 2011-04-01 2011-04-01 false Test procedure for roof trusses... procedure for roof trusses. (a) Roof load tests. The following is an acceptable test procedure, consistent with the provisions of § 3280.401, for roof trusses that are supported at the ends and support...

  1. 24 CFR 3280.402 - Test procedure for roof trusses.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 5 2013-04-01 2013-04-01 false Test procedure for roof trusses... procedure for roof trusses. Link to an amendment published at 78 FR 4065, Jan. 18, 2013. (a) Roof load tests... trusses that are supported at the ends and support design loads. Where roof trusses act as support...

  2. 24 CFR 3280.402 - Test procedure for roof trusses.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Test procedure for roof trusses... procedure for roof trusses. (a) Roof load tests. The following is an acceptable test procedure, consistent with the provisions of § 3280.401, for roof trusses that are supported at the ends and support...

  3. Western Wind and Solar Integration Study Phase 3 -- Frequency Response and Transient Stability (Report and Executive Summary)

    SciTech Connect

    Miller, N. W.; Shao, M.; Pajic, S.; D'Aquila, R.

    2014-12-01

    The primary objectives of Phase 3 of the Western Wind and Solar Integration Study (WWSIS-3) were to examine the large-scale transient stability and frequency response of the Western Interconnection with high wind and solar penetration, and to identify means to mitigate any adverse performance impacts via transmission reinforcements, storage, advanced control capabilities, or other alternatives.

  4. Solar Electric Propulsion System Integration Technology (SEPSIT). Volume 2: Encke rendezvous mission and space vehicle functional description

    NASA Technical Reports Server (NTRS)

    Gardner, J. A.

    1972-01-01

    A solar electric propulsion system integration technology study is discussed. Detailed analyses in support of the solar electric propulsion module were performed. The thrust subsystem functional description is presented. The space vehicle and the space mission to which the propulsion system is applied are analyzed.

  5. Green roofs for a drier world: effects of hydrogel amendment on substrate and plant water status.

    PubMed

    Savi, Tadeja; Marin, Maria; Boldrin, David; Incerti, Guido; Andri, Sergio; Nardini, Andrea

    2014-08-15

    Climate features of the Mediterranean area make plant survival over green roofs challenging, thus calling for research work to improve water holding capacities of green roof systems. We assessed the effects of polymer hydrogel amendment on the water holding capacity of a green roof substrate, as well as on water status and growth of Salvia officinalis. Plants were grown in green roof experimental modules containing 8 cm or 12 cm deep substrate (control) or substrate mixed with hydrogel at two different concentrations: 0.3 or 0.6%. Hydrogel significantly increased the substrate's water content at saturation, as well as water available to vegetation. Plants grown in 8 cm deep substrate mixed with 0.6% of hydrogel showed the best performance in terms of water status and membrane integrity under drought stress, associated to the lowest above-ground biomass. Our results provide experimental evidence that polymer hydrogel amendments enhance water supply to vegetation at the establishment phase of a green roof. In particular, the water status of plants is most effectively improved when reduced substrate depths are used to limit the biomass accumulation during early growth stages. A significant loss of water holding capacity of substrate-hydrogel blends was observed after 5 months from establishment of the experimental modules. We suggest that cross-optimization of physical-chemical characteristics of hydrogels and green roof substrates is needed to improve long term effectiveness of polymer-hydrogel blends. PMID:24867709

  6. Building integrated PV for commercial industry

    SciTech Connect

    Eiffert, P.; Kiss, G.

    2000-02-14

    This sourcebook on building-integrated photovoltaics (BIPV) is intended for architects and designers interested in learning more about today's sustainable solar buildings. The booklet includes 16 design briefs describing actual structures; they illustrate how electricity-generating BIPV products (such as special roofing systems, vertical-wall systems, skylights, and awnings, all of which contain PV cells, modules, and films) can be integrated successfully into many different kinds of buildings. It also contains basic information about BIPV technologies, an overview of US product development activities and development programs, descriptions of major software design tools, and a bibliography.

  7. Energy factors and temperature distribution in insulated built-up roofs. Technical note July 1977-January 1980

    SciTech Connect

    Keeton, J.R.; Alumbaugh, R.L.

    1981-02-01

    Surface temperatures of 4-ply built-up roofs insulated with (1) 1 inch of perlite (R = 2.8) and 2-1/2 inches of urethane (R = 19.2) and (2) 1 inch of urethane (R = 7.1) and 1-7/8 inches of glass fiber (R = 7.7) are presented. Energy factors are shown in terms of temperature-time areas defined as solar heat response, cooling (heating) required, radiative cooling, and insulation efficiency. Results indicate that for a black surface, solar heat response is significantly higher in the roof portion with the higher R-value. Solar heat response is directly affected by color of surfacing; lowest to highest values were found with white, white gravel, gray gravel, aluminum-gray, and black. Recommendations are given for reducing surface temperatures of insulated built-up roofs.

  8. Metal and nutrient dynamics on an aged intensive green roof.

    PubMed

    Speak, A F; Rothwell, J J; Lindley, S J; Smith, C L

    2014-01-01

    Runoff and rainfall quality was compared between an aged intensive green roof and an adjacent conventional roof surface. Nutrient concentrations in the runoff were generally below Environmental Quality Standard (EQS) values and the green roof exhibited NO3(-) retention. Cu, Pb and Zn concentrations were in excess of EQS values for the protection of surface water. Green roof runoff was also significantly higher in Fe and Pb than on the bare roof and in rainfall. Input-output fluxes revealed the green roof to be a potential source of Pb. High concentrations of Pb within the green roof soil and bare roof dusts provide a potential source of Pb in runoff. The origin of the Pb is likely from historic urban atmospheric deposition. Aged green roofs may therefore act as a source of legacy metal pollution. This needs to be considered when constructing green roofs with the aim of improving pollution remediation. PMID:24017999

  9. Cool Roofs Through Time and Space

    SciTech Connect

    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

  10. Carbon sequestration potential of extensive green roofs.

    PubMed

    Getter, Kristin L; Rowe, D Bradley; Robertson, G Philip; Cregg, Bert M; Andresen, Jeffrey A

    2009-10-01

    Two studies were conducted with the objective of quantifying the carbon storage potential of extensive green roofs. The first was performed on eight roofs in Michigan and four roofs in Maryland, ranging from 1 to 6 years in age. All 12 green roofs were composed primarily of Sedum species, and substrate depths ranged from 2.5 to 12.7 cm. Aboveground plant material was harvested in the fall of 2006. On average, these roofs stored 162 g C x m(-2) in aboveground biomass. The second study was conducted on a roof in East Lansing, MI. Twenty plots were established on 21 April 2007 with a substrate depth of 6.0 cm. In addition to a substrate only control, the other plots were sown with a single species of Sedum (S. acre, S. album, S. kamtshaticum, or S. spurium). Species and substrate depth represent typical extensive green roofs in the United States. Plant material and substrate were harvested seven times across two growing seasons. Results at the end of the second year showed that aboveground plant material storage varied by species, ranging from 64 g C x m(-2) (S. acre) to 239 g C x m(-2) (S. album), with an average of 168 g C x m(-2). Belowground biomass ranged from 37 g C x m(-2) (S. acre) to 185 g C x m(-2) (S. kamtschaticum) and averaged 107 g C x m(-2). Substrate carbon content averaged 913 g C x m(-2), with no species effect, which represents a sequestration rate of 100 g C x m(-2) over the 2 years of this study. The entire extensive green roof system sequestered 375 g C x m(-2) in above- and belowground biomass and substrate organic matter. PMID:19848177

  11. Career Directions--Renewable Energy Systems Integrator

    ERIC Educational Resources Information Center

    Fleeman, Stephen R.

    2012-01-01

    Renewable energy systems are beginning to appear everywhere. Solar modules are creating "blue roofs" that convert the energy from the sun into household electricity. Solar thermal systems on roofs can generate hot water. Wind turbines catch breezes to provide even more electricity. Recommendations for saving energy, specifying systems for

  12. Career Directions--Renewable Energy Systems Integrator

    ERIC Educational Resources Information Center

    Fleeman, Stephen R.

    2012-01-01

    Renewable energy systems are beginning to appear everywhere. Solar modules are creating "blue roofs" that convert the energy from the sun into household electricity. Solar thermal systems on roofs can generate hot water. Wind turbines catch breezes to provide even more electricity. Recommendations for saving energy, specifying systems for…

  13. Sloshing impact in roofed tanks

    SciTech Connect

    Uras, R.A.

    1995-07-01

    A large number of high-level waste (HLW) storage tanks exists in various tank farms. Seismic activities at those locations may cause significant sloshing in HLW tanks. These tanks are covered to avoid any spilling during large amplitude earthquakes. However, large amplitude sloshing may result in impact on the cover or the roof of the tank. Hence, a better understanding of the impact phenomenon is necessary to assess the safety of the tanks currently in existence, and to establish design guidelines for future designs. A pressure based formulation is derived to model sloshing impact in roared tanks. It is incorporated into Argonne`s in-house finite element code FLUSTR-ANL. A numerical test case with a harmonic input excitation is studied. The simulation results indicate that linear behavior is preserved beyond the first impact, and some mesh distortion is observed following a stronger second impact. During the impact, the displacement of the contacting surface nodes remains constant, and the velocities are reduced to zero. An identification of impacting nodes is possible from the dynamic pressures induced in surface elements.

  14. Liquid storage tank with floating roof structure

    SciTech Connect

    Vaughn, L.G.

    1993-07-27

    In a cylindrical wall storage tank for containing a liquid, said tank is described having a floor, a floatable roof supportable by said contained liquid, said roof including a peripheral seal for engaging the cylindrical wall to maintain a fluid-tight sliding seal therewith, and support means associated with said roof including, the improvement in said tank of, at least one cylindrical guide sleeve extending downwardly from said floatable roof; a shoe depending laterally from said at least one cylindrical guide sleeve's lower end for engaging the tank floor when the level of contained liquid is insufficient to support said floatable roof, said shoe having means forming a passage there through to register a support column and, an elongated support column removably positioned in said at least one cylindrical guide sleeve, of being sufficient length to extend downward beyond the shoe to engage the tank floor, whereby to sustain the floatable roof a predetermined distance above said floor after the contained liquid has drained from the tank.

  15. Performance of 3-sun mirror modules on sun tracking carousels on flat roof buildings

    NASA Astrophysics Data System (ADS)

    Fraas, Lewis; Avery, James; Minkin, Leonid; Maxey, Curt; Gehl, Tony; Hurt, Rick; Boehm, Robert

    2008-08-01

    Commercial buildings represent a near term market for cost competitive solar electric power provided installation costs and solar photovoltaic module costs can be reduced. JX Crystals has developed a carousel sun tracker that is prefabricated and can easily be deployed on building flat roof tops without roof penetration. JX Crystals is also developing 3-sun PV mirror modules where less expensive mirrors are substituted for two-thirds of the expensive single crystal silicon solar cell surface area. Carousels each with four 3-sun modules have been set up at two sites, specifically at Oak Ridge National Lab and at the University of Nevada in Las Vegas. The test results for these systems are presented.

  16. Integrated Orbit, Attitude, and Structural Control System Design for Space Solar Power Satellites

    NASA Technical Reports Server (NTRS)

    Woods-Vedeler, Jessica (Technical Monitor); Moore, Chris (Technical Monitor); Wie, Bong; Roithmayr, Carlos

    2001-01-01

    The major objective of this study is to develop an integrated orbit, attitude, and structural control system architecture for very large Space Solar Power Satellites (SSPS) in geosynchronous orbit. This study focuses on the 1.2-GW Abacus SSPS concept characterized by a 3.2 x 3.2 km solar-array platform, a 500-m diameter microwave beam transmitting antenna, and a 500 700 m earth-tracking reflector. For this baseline Abacus SSPS configuration, we derive and analyze a complete set of mathematical models, including external disturbances such as solar radiation pressure, microwave radiation, gravity-gradient torque, and other orbit perturbation effects. The proposed control system architecture utilizes a minimum of 500 1-N electric thrusters to counter, simultaneously, the cyclic pitch gravity-gradient torque, the secular roll torque caused by an o.set of the center-of-mass and center-of-pressure, the cyclic roll/yaw microwave radiation torque, and the solar radiation pressure force whose average value is about 60 N.

  17. Integrated Orbit, Attitude, and Structural Control Systems Design for Space Solar Power Satellites

    NASA Technical Reports Server (NTRS)

    Wie, Bong; Roithmayr, Carlos M.

    2001-01-01

    The major objective of this study is to develop an integrated orbit, attitude, and structural control systems architecture for very large Space Solar Power Satellites (SSPS) in geosynchronous orbit. This study focuses on the 1.2-GW Abacus SSPS concept characterized by a 3.2 x 3.2 km solar-array platform, a 500-m diameter microwave beam transmitting antenna, and a 500 x 700 m earth-tracking reflector. For this baseline Abacus SSPS configuration, we derive and analyze a complete set of mathematical models, including external disturbances such as solar radiation pressure, microwave radiation, gravity-gradient torque, and other orbit perturbation effects. The proposed control systems architecture utilizes a minimum of 500 1-N electric thrusters to counter, simultaneously, the cyclic pitch gravity-gradient torque, the secular roll torque caused by an offset of the center-of-mass and center-of-pressure, the cyclic roll/yaw microwave radiation torque, and the solar radiation pressure force whose average value is about 60 N.

  18. The effect of roof strength on reducing occupant injury in rollovers.

    PubMed

    Herbst, Brian; Forrest, Steve; Orton, Tia; Meyer, Steven E; Sances, Anthony; Kumaresan, Srirangam

    2005-01-01

    Roof crush occurs and potentially contributes to serious or fatal occupant injury in 26% of rollovers. It is likely that glazing retention is related to the degree of roof crush experienced in rollover accidents. Occupant ejection (including partial ejection) is the leading cause of death and injury in rollover accidents. In fatal passenger car accidents involving ejection, 34% were ejected through the side windows. Side window glass retention during a rollover is likely to significantly reduce occupant ejections. The inverted drop test methodology is a test procedure to evaluate the structural integrity of roofs under loadings similar to those seen in real world rollovers. Recent testing on many different vehicle types indicates that damage consistent with field rollover accidents can be achieved through inverted drop testing at very small drop heights. Drop test comparisons were performed on 16 pairs of vehicles representing a large spectrum of vehicle types. Each vehicle pair includes a production vehicle and a vehicle with a reinforced roof structure dropped under the same test conditions. This paper offers several examples of post-production reinforcements to roof structures that significantly increase the crush resistance of the roof as measured by inverted drop tests. These modifications were implemented with minimal impact on vehicle styling, interior space and visual clearances. The results of these modifications indicate that roof crush can be mitigated by nearly an order of magnitude, as roof crush was reduced by 44-91% with only a 1-2.3% increase in vehicle weight. Additionally, this paper analyzes the glazing breakage patterns in the moveable tempered side windows on the side adjacent to the vehicle impact point in the inverted drop tests. A comparison is made between the production vehicles and the reinforced vehicles in order to determine if the amount roof crush is related to glazing integrity in the side windows. Lastly, two drop test pairs, performed with Hybrid III test dummies, indicates that the reduction of roof crush resulted in a direct reduction in neck loading and therefore an increase in occupant protection. PMID:15850089

  19. Solar Ready: An Overview of Implementation Practices

    SciTech Connect

    Watson, A.; Guidice, L.; Lisell, L.; Doris, L.; Busche, S.

    2012-01-01

    This report explores three mechanisms for encouraging solar ready building design and construction: solar ready legislation, certification programs for solar ready design and construction, and stakeholder education. These methods are not mutually exclusive, and all, if implemented well, could contribute to more solar ready construction. Solar ready itself does not reduce energy use or create clean energy. Nevertheless, solar ready building practices are needed to reach the full potential of solar deployment. Without forethought on incorporating solar into design, buildings may be incompatible with solar due to roof structure or excessive shading. In these cases, retrofitting the roof or removing shading elements is cost prohibitive. Furthermore, higher up-front costs due to structural adaptations and production losses caused by less than optimal roof orientation, roof equipment, or shading will lengthen payback periods, making solar more expensive. With millions of new buildings constructed each year in the United States, solar ready can remove installation barriers and increase the potential for widespread solar adoption. There are many approaches to promoting solar ready, including solar ready legislation, certification programs, and education of stakeholders. Federal, state, and local governments have the potential to implement programs that encourage solar ready and in turn reduce barriers to solar deployment. With the guidance in this document and the examples of jurisdictions and organizations already working to promote solar ready building practices, federal, state, and local governments can guide the market toward solar ready implementation.

  20. Lightweight Integrated Solar Array (LISA): Providing Higher Power to Small Spacecraft

    NASA Technical Reports Server (NTRS)

    Johnson, Les; Carr, John; Fabisinski, Leo; Lockett, Tiffany Russell

    2015-01-01

    Affordable and convenient access to electrical power is essential for all spacecraft and is a critical design driver for the next generation of smallsats, including CubeSats, which are currently extremely power limited. The Lightweight Integrated Solar Array (LISA), a concept designed, prototyped, and tested at the NASA Marshall Space Flight Center (MSFC) in Huntsville, Alabama provides an affordable, lightweight, scalable, and easily manufactured approach for power generation in space. This flexible technology has many wide-ranging applications from serving small satellites to providing abundant power to large spacecraft in GEO and beyond. By using very thin, ultraflexible solar arrays adhered to an inflatable or deployable structure, a large area (and thus large amount of power) can be folded and packaged into a relatively small volume.

  1. Advancements of the Lightweight Integrated Solar Array and Transceiver (LISA-T) Small Spacecraft System

    NASA Technical Reports Server (NTRS)

    Russell, Tiffany; Martinez, Armando; Boyd, Darren; SanSoucie, Michael; Farmer, Brandon; Schneider, Todd; Fabisinski, Leo; Johnson, Les; Carr, John A.

    2015-01-01

    This paper describes recent advancements of the Lightweight Integrated Solar Array and Transceiver (LISA-T) currently being developed at NASA's Marshall Space Flight Center. The LISA-T array comprises a launch stowed, orbit deployed structure on which thin-film photovoltaic (PV) and antenna devices are embedded. The system provides significant electrical power generation at low weights, high stowage efficiency, and without the need for solar tracking. Leveraging high-volume terrestrial-market PVs also gives the potential for lower array costs. LISA-T is addressing the power starvation epidemic currently seen by many small-scale satellites while also enabling the application of deployable antenna arrays. Herein, an overview of the system and its applications are presented alongside sub-system development progress and environmental testing plans/initial results.

  2. Advancements of the Lightweight Integrated Solar Array and Transceiver (LISA-T) Small Spacecraft System

    NASA Technical Reports Server (NTRS)

    Lockett, Tiffany Russell; Martinez, Armando; Boyd, Darren; SanSouice, Michael; Farmer, Brandon; Schneider, Todd; Laue, Greg; Fabisinski, Leo; Johnson, Les; Carr, John A.

    2015-01-01

    This paper describes recent advancements of the Lightweight Integrated Solar Array and Transceiver (LISA-T) currently being developed at NASA's Marshall Space Flight Center. The LISA-T array comprises a launch stowed, orbit deployed structure on which thin-film photovoltaic (PV) and antenna devices are embedded. The system provides significant electrical power generation at low weights, high stowage efficiency, and without the need for solar tracking. Leveraging high-volume terrestrial-market PVs also gives the potential for lower array costs. LISA-T is addressing the power starvation epidemic currently seen by many small-scale satellites while also enabling the application of deployable antenna arrays. Herein, an overview of the system and its applications are presented alongside sub-system development progress and environmental testing plans.

  3. Simulation tests to assess occupational exposure to airborne asbestos from artificially weathered asphalt-based roofing products.

    PubMed

    Sheehan, Patrick; Mowat, Fionna; Weidling, Ryan; Floyd, Mark

    2010-11-01

    Historically, asbestos-containing roof cements and coatings were widely used for patching and repairing leaks. Although fiber releases from these materials when newly applied have been studied, there are virtually no useful data on airborne asbestos fiber concentrations associated with the repair or removal of weathered roof coatings and cements, as most studies involve complete tear-out of old roofs, rather than only limited removal of the roof coating or cement during a repair job. This study was undertaken to estimate potential chrysotile asbestos fiber exposures specific to these types of roofing products following artificially enhanced weathering. Roof panels coated with plastic roof cement and fibered roof coating were subjected to intense solar radiation and daily simulated precipitation events for 1 year and then scraped to remove the weathered materials to assess chrysotile fiber release and potential worker exposures. Analysis of measured fiber concentrations for hand scraping of the weathered products showed 8-h time-weighted average concentrations that were well below the current Occupational Safety and Health Administration permissible exposure limit for asbestos. There was, however, visibly more dust and a few more fibers collected during the hand scraping of weathered products compared to the cured products previously tested. There was a notable difference between fibers released from weathered and cured roofing products. In weathered samples, a large fraction of chrysotile fibers contained low concentrations of or essentially no magnesium and did not meet the spectral, mineralogical, or morphological definitions of chrysotile asbestos. The extent of magnesium leaching from chrysotile fibers is of interest because several researchers have reported that magnesium-depleted chrysotile fibers are less toxic and produce fewer mesothelial tumors in animal studies than normal chrysotile fibers. PMID:20923966

  4. Solar home on the range

    SciTech Connect

    Wainwright, K.

    1999-10-01

    Solar technologies and indigenous materials are used in this remote Texas ranch house. Passive solar, thermal mass of adobe walls, photovoltaics, wood stoves, native stone, a ventilated roof, reflective barrier, and porch overhangs surrounding the house combine to keep the house comfortable all summer. The PV system used a passive solar tracking system that increased the electrical output by an overall 29 percent.

  5. Study on functional integration of the SKA and the solar thermal power system

    NASA Astrophysics Data System (ADS)

    Dong, Zhi-Ming; Yang, Dehua; Zhang, Yong; Zhou, Xuebin

    2012-09-01

    A separate building of solar power plants may take hundreds of millions of euros. The dish-stirling system is one of the concentrating solar thermal power (CSP) technologies. Considering the dish-stirling system is structurally similar to a radio telescope, with its diameter similar to the antenna that is used in the SKA, It is assumed that a radio telescope and the dish-stirling system could be functionally integrated in the design for time-based sharing, thus to reduce the SKA and the dish-stirling system in the repeated construction costs on the reflecting surface, the two-axis tracking mechanism, the civil engineering, and the roads, etc. Based on the above idea on the functional integration of devices, whilst taking account on the functional requirements of the SKA and the dish-stirling system, the Principle design of functional integration is conducted. In addition, the control system and multi-functional reflector regarding its processing and coating technology is covered.

  6. 40 CFR 65.45 - External floating roof converted into an internal floating roof.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false External floating roof converted into an internal floating roof. 65.45 Section 65.45 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Storage Vessels §...

  7. 40 CFR 65.43 - Fixed roof with an internal floating roof (IFR).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... floating roof is resting on the leg supports, the process of filling or refilling shall be continuous and... in § 65.47(e). (3) Automatic bleeder vents are to be set to be closed at all times when the roof is... maintained in a closed position at all times (i.e., no visible gaps) except when the device is in actual...

  8. Prospects for integrating utility-scale solar photovoltaics and industrial agriculture in the U.S

    NASA Astrophysics Data System (ADS)

    Dahlin, K.; Anderegg, W.; Hernandez, R. R.; Hiza, N.; Johnson, J. E.; Maltais-landry, G.; Wolf, A.; Zimmerman, N. B.

    2011-12-01

    One of the key challenges to many alternative energy options is land use competition, such as conflict with food production (e.g., corn or sugar cane ethanol) or natural resource protection (e.g., solar panels in desert habitat). Wind power has largely avoided these conflicts by leasing land from farmers and maintaining a small footprint on the landscape. Here, we ask whether similar opportunities exist for solar photovoltaics in agricultural settings. Our test case consists of a soybean field in Ames, Iowa (USA), with south-facing solar panels in rows spaced 16 m apart (~3 times further than typical), a center pole height of 3 m (3 times higher than in a typical ground-mounted system), and a fixed tilt of 25 degrees. Using a geometric shade model coupled to a common crop model (DSSAT) and driven by 14 years of weather data, we find that the average annual soybean yield is not significantly reduced (< 3% or < 0.1 t ha-1 yr-1) by the shade cast by the solar panels. Furthermore, shading appears to slightly improve yields during dry years. These results are consistent across five soybean cultivars spanning the three maturity groups commonly grown in Iowa, suggesting that incorporation of solar photovoltaics into agricultural fields may provide renewable energy with little or no reduction in yields. Using the National Renewable Energy Laboratory (NREL) System Advisor Model and assuming 18 to 20% efficient panels, we estimate that this configuration at this location will produce 295 MWh ha-1 in the first year of operation. With this configuration the United States' current (2007) electricity production could be met by incorporating photovoltaic panels into as little as 11% of currently cropped land. We are currently developing an independent model that will complement our DSSAT analyses by simulating the effects of solar photovoltaics on available light, albedo and temperature on a range of different crops. We also review some of the major challenges to and potential benefits of integrated solar-agricultural systems in different regions and cropping systems.

  9. Solar thermal vacuum testing of an integrated membrane concentrator system at the NASA GRC tank 6

    NASA Astrophysics Data System (ADS)

    Pearson, James C.; Lester, Dean M.; Holmes, Michael R.; Wong, Wayne A.

    2002-01-01

    This paper reports the results of recent highly integrated thermal vacuum testing of key components of a membrane concentrator system. The Dual Use Science and Technology (DUS&T) Electromagnetic Radiation Control Experiment (EMRCE) Team, including SRS Technologies, ATK Thiokol Propulsion, Boeing, Air Force Research Laboratory (AFRL), and National Aeronautics and Space Administration (NASA) is chartered to partner industry with government to develop flight qualified membrane structures. Specifically, DUS&T EMRCE aims to complete development of membrane concentrator technologies to achieve flight experiment readiness in anticipation of a near term flight experiment opportunity. Potential flight experiments are in the areas of solar thermal propulsion, space power, and RF communications. .

  10. Analysis of Cycling Costs in Western Wind and Solar Integration Study

    SciTech Connect

    Jordan, G.; Venkataraman, S.

    2012-06-01

    The Western Wind and Solar Integration Study (WWSIS) examined the impact of up to 30% penetration of variable renewable generation on the Western Electricity Coordinating Council system. Although start-up costs and higher operating costs because of part-load operation of thermal generators were included in the analysis, further investigation of additional costs associated with thermal unit cycling was deemed worthwhile. These additional cycling costs can be attributed to increases in capital as well as operations and maintenance costs because of wear and tear associated with increased unit cycling. This analysis examines the additional cycling costs of the thermal fleet by leveraging the results of WWSIS Phase 1 study.

  11. Data Distribution System (DDS) and Solar Dynamic Observatory Ground Station (SDOGS) Integration Manager

    NASA Technical Reports Server (NTRS)

    Pham, Kim; Bialas, Thomas

    2012-01-01

    The DDS SDOGS Integration Manager (DSIM) provides translation between native control and status formats for systems within DDS and SDOGS, and the ASIST (Advanced Spacecraft Integration and System Test) control environment in the SDO MOC (Solar Dynamics Observatory Mission Operations Center). This system was created in response for a need to centralize remote monitor and control of SDO Ground Station equipments using ASIST control environment in SDO MOC, and to have configurable table definition for equipment. It provides translation of status and monitoring information from the native systems into ASIST-readable format to display on pages in the MOC. The manager is lightweight, user friendly, and efficient. It allows data trending, correlation, and storing. It allows using ASIST as common interface for remote monitor and control of heterogeneous equipments. It also provides failover capability to back up machines.

  12. The Abacus/Reflector and Integrated Symmetrical Concentrator: Concepts for Space Solar Power Collection and Transmission

    NASA Technical Reports Server (NTRS)

    Carrington, Connie; Fikes, John; Gerry, Mark; Perkinson, Don

    2000-01-01

    New energy sources are vital for the development of emerging nations, and the growth of industry in developed economies. Also vital is the need for these energy sources to be clean and renewable. For the past several years, NASA has been taking a new look at collecting solar energy in space and transmitting it to Earth, to planetary surfaces, and to orbiting spacecraft. Several innovative concepts are being studied for the space segment component of solar power beaming. One is the Abacus/Reflector, a large sun-oriented array structure fixed to the transmitter, and a rotating RF reflector that tracks a receiving rectenna on Earth. This concept eliminates the need for power-conducting slip rings in rotating joints between the solar collectors and the transmitter. Another concept is the Integrated Symmetrical Concentrator (ISC), composed of two very large segmented reflectors which rotate to collect and reflect the incident sunlight onto two centrally-located photovoltaic arrays. Adjacent to the PV arrays is the RF transmitter, which as a unit track the receiving rectenna, again eliminating power-conducting joints, and in addition reducing the cable lengths between the arrays and transmitter. The metering structure to maintain the position of the reflectors is a long mast, oriented perpendicular to the equatorial orbit plane. This paper presents a status of ongoing systems studies and configurations for the Abacus/Reflector and the ISC concepts, and a top-level study of packaging for launch and assembly.

  13. Modelling Concentrating Solar Power with Thermal Energy Storage for Integration Studies (Presentation)

    SciTech Connect

    Hummon, M.; Jorgenson, J.; Denholm, P.; Mehos, M.

    2013-10-01

    Concentrating solar power with thermal energy storage (CSP-TES) can provide multiple benefits to the grid, including low marginal cost energy and the ability to levelize load, provide operating reserves, and provide firm capacity. It is challenging to properly value the integration of CSP because of the complicated nature of this technology. Unlike completely dispatchable fossil sources, CSP is a limited energy resource, depending on the hourly and daily supply of solar energy. To optimize the use of this limited energy, CSP-TES must be implemented in a production cost model with multiple decision variables for the operation of the CSP-TES plant. We develop and implement a CSP-TES plant in a production cost model that accurately characterizes the three main components of the plant: solar field, storage tank, and power block. We show the effect of various modelling simplifications on the value of CSP, including: scheduled versus optimized dispatch from the storage tank and energy-only operation versus co-optimization with ancillary services.

  14. Modelling Concentrating Solar Power with Thermal Energy Storage for Integration Studies: Preprint

    SciTech Connect

    Hummon, M.; Denholm, P.; Jorgenson, J.; Mehos, M.

    2013-10-01

    Concentrating solar power with thermal energy storage (CSP-TES) can provide multiple benefits to the grid, including low marginal cost energy and the ability to levelize load, provide operating reserves, and provide firm capacity. It is challenging to properly value the integration of CSP because of the complicated nature of this technology. Unlike completely dispatchable fossil sources, CSP is a limited energy resource, depending on the hourly and daily supply of solar energy. To optimize the use of this limited energy, CSP-TES must be implemented in a production cost model with multiple decision variables for the operation of the CSP-TES plant. We develop and implement a CSP-TES plant in a production cost model that accurately characterizes the three main components of the plant: solar field, storage tank, and power block. We show the effect of various modelling simplifications on the value of CSP, including: scheduled versus optimized dispatch from the storage tank and energy-only operation versus co-optimization with ancillary services.

  15. Integrated three-dimensional photonic nanostructures for achieving near-unity solar absorption and superhydrophobicity

    SciTech Connect

    Kuang, Ping; Lin, Shawn-Yu; Hsieh, Mei-Li

    2015-06-07

    In this paper, we proposed and realized 3D photonic nanostructures consisting of ultra-thin graded index antireflective coatings (ARCs) and woodpile photonic crystals. The use of the integrated ARC and photonic crystal structure can achieve broadband, broad-angle near unity solar absorption. The amorphous silicon based photonic nanostructure experimentally shows an average absorption of ∼95% for λ = 400–620 nm over a wide angular acceptance of θ = 0°–60°. Theoretical studies show that a Gallium Arsenide (GaAs) based structure can achieve an average absorption of >95% for λ = 400–870 nm. Furthermore, the use of the slanted SiO{sub 2} nanorod ARC surface layer by glancing angle deposition exhibits Cassie-Baxter state wetting, and superhydrophobic surface is obtained with highest water contact angle θ{sub CB} ∼ 153°. These properties are fundamentally important for achieving maximum solar absorption and surface self-cleaning in thin film solar cell applications.

  16. Integration of Light Trapping Silver Nanostructures in Hydrogenated Microcrystalline Silicon Solar Cells by Transfer Printing.

    PubMed

    Mizuno, Hidenori; Sai, Hitoshi; Matsubara, Koji; Takato, Hidetaka; Kondo, Michio

    2015-01-01

    One of the potential applications of metal nanostructures is light trapping in solar cells, where unique optical properties of nanosized metals, commonly known as plasmonic effects, play an important role. Research in this field has, however, been impeded owing to the difficulty of fabricating devices containing the desired functional metal nanostructures. In order to provide a viable strategy to this issue, we herein show a transfer printing-based approach that allows the quick and low-cost integration of designed metal nanostructures with a variety of device architectures, including solar cells. Nanopillar poly(dimethylsiloxane) (PDMS) stamps were fabricated from a commercially available nanohole plastic film as a master mold. On this nanopatterned PDMS stamps, Ag films were deposited, which were then transfer-printed onto block copolymer (binding layer)-coated hydrogenated microcrystalline Si (µc-Si:H) surface to afford ordered Ag nanodisk structures. It was confirmed that the resulting Ag nanodisk-incorporated µc-Si:H solar cells show higher performances compared to a cell without the transfer-printed Ag nanodisks, thanks to plasmonic light trapping effect derived from the Ag nanodisks. Because of the simplicity and versatility, further device application would also be feasible thorough this approach. PMID:26575244

  17. Structural Integration of Silicon Solar Cells and Lithium-ion Batteries Using Printed Electronics

    NASA Astrophysics Data System (ADS)

    Kang, Jin Sung

    Inkjet printing of electrode using copper nanoparticle ink is presented. Electrode was printed on a flexible glass epoxy composite substrate using drop on demand piezoelectric dispenser and was sintered at 200°C in N 2 gas condition. The printed electrodes were made with various widths and thicknesses. Surface morphology of electrode was analyzed using scanning electron microscope (SEM) and atomic force microscope (AFM). Reliable dimensions for printed electronics were found from this study. Single-crystalline silicon solar cells were tested under four-point bending to find the feasibility of directly integrating them onto a carbon fiber/epoxy composite laminate. These solar cells were not able to withstand 0.2% strain. On the other hand, thin-film amorphous silicon solar cells were subjected to flexural fatigue loadings. The current density-voltage curves were analyzed at different cycles, and there was no noticeable degradation on its performance up to 100 cycles. A multifunctional composite laminate which can harvest and store solar energy was fabricated using printed electrodes. The integrated printed circuit board (PCB) was co-cured with a carbon/epoxy composite laminate by the vacuum bag molding process in an autoclave; an amorphous silicon solar cell and a thin-film solid state lithium-ion (Li-ion) battery were adhesively joined and electrically connected to a thin flexible PCB; and then the passive components such as resistors and diodes were electrically connected to the printed circuit board by silver pasting. Since a thin-film solid state Li-ion battery was not able to withstand tensile strain above 0.4%, thin Li-ion polymer batteries were tested under various mechanical loadings and environmental conditions to find the feasibility of using the polymer batteries for our multifunctional purpose. It was found that the Li-ion polymer batteries were stable under pressure and tensile loading without any noticeable degradation on its charge and discharge performances. Also, the active materials did not decompose at 80°C, and the battery was performing well under low temperature of -27°C. Lastly, the batteries were embedded inside a carbon fiber/epoxy composite laminate to characterize their performance under fatigue loading. Finally, an intense pulsed light (IPL) was used to sinter printed silver nanoink patterns. X-ray diffraction (XRD) was used to find grain size of printed silver nanoink patterns. From these analyses it was confirmed that IPL is able to adequately sinter silver nanoink patterns for printed electronics without degradation of the substrates in less than 30 ms.

  18. Building-integrated photovoltaics: A case study

    NASA Astrophysics Data System (ADS)

    Kiss, G.; Kinkead, J.; Raman, M.

    1995-03-01

    In 1992, Kiss Cathcart Anders Architects performed a study for NREL on Building-Integrated Photovoltaics (BIPV) issues as seen from the perspective of the building community. In general, the purpose of the study was to list major issues and potential applications; by it's nature it asked more questions than it answered. This second phase study was to produce quantitative data on the performance of specific BIPV systems. Only roof systems are evaluated. The energy performance, construction cost and simple payback for five different BIPV roof options are evaluated in six different locations: Oakland, New York, Miami, Phoenix, Chicago, and Cincinnati. The roof options evaluated include the following: single-glazed PV roof using glass-substrate PVs; double-glazed PV roof with insulating PV modules; ballasted roof-mounted system; sawtooth light monitor roof with indirect north daylighting; sawtooth roof with north light and active heat recovery.

  19. Building-integrated photovoltaics: A case study

    SciTech Connect

    Kiss, G.; Kinkead, J.; Raman, M.

    1995-03-01

    In 1992, Kiss Cathcart Anders Architects performed a study for NREL on Building-Integrated Photovoltaics (BIPV) issues as seen from the perspective of the building community. In general, the purpose of the study was to list major issues and potential applications; by it`s nature it asked more questions than it answered. This second phase study was to produce quantitative data on the performance of specific BIPV systems. Only roof systems are evaluated. The energy performance, construction cost and simple payback for five different BIPV roof options are evaluated in six different locations: Oakland, New York, Miami, Phoenix, Chicago, and Cincinnati. The roof options evaluated include the following: single-glazed PV roof using glass-substrate PVs; double-glazed PV roof with insulating PV modules; ballasted roof-mounted system; sawtooth light monitor roof with indirect north daylighting; sawtooth roof with north light and active heat recovery.

  20. Roofing as a source of nonpoint water pollution.

    PubMed

    Chang, Mingteh; McBroom, Matthew W; Scott Beasley, R

    2004-12-01

    Sixteen wooden structures with two roofs each were installed to study runoff quality for four commonly used roofing materials (wood shingle, composition shingle, painted aluminum, and galvanized iron) at Nacogdoches, Texas. Each roof, either facing NW or SE, was 1.22 m wide x 3.66 m long with a 25.8% roof slope. Thus, there were 32 alternatively arranged roofs, consisting of four roof types x two aspects x four replicates, in the study. Runoff from the roofs was collected through galvanized gutters, downspouts, and splitters. The roof runoff was compared to rainwater collected by a wet/dry acid rain collector for the concentrations of eight water quality variables, i.e. Cu(2+), Mn(2+), Pb(2+), Zn(2+), Mg(2+), Al(3+), EC and pH. Based on 31 storms collected between October 1997 and December 1998, the results showed: (1) concentrations of pH, Cu, and Zn in rainwater already exceed the EPA freshwater quality standards even without pollutant inputs from roofs, (2) Zn and Cu, the two most serious pollutants in roof runoff, exceeded the EPA national freshwater water quality standards in virtually 100% and more than 60% of the samples, respectively, (3) pH, EC, and Zn were the only three variables significantly affected by roofing materials, (4) differences in Zn concentrations were significant among all roof types and between all roof runoff and rainwater samples, (5) although there were no differences in Cu concentrations among all roof types and between roof runoff and rainwater, all means and medians of runoff and rainwater exceeded the national water quality standards, (6) water quality from wood shingles was the worst among the roof types studied, and (7) although SE is the most frequent and NW the least frequent direction for incoming storms, only EC, Mg, Mn, and Zn in wood shingle runoff from the SE were significantly higher than those from the NW; the two aspects affected no other elements in runoff from the other three roof types. Also, Zn concentrations from new wood-shingle roofs were significantly higher than those from aged roofs of a previous study. The study demonstrated that roofs could be a serious source of nonpoint water pollution. Since Zn is the most serious water pollutant and wood shingle is the worst of the four roof types, using less compounds and materials associated with Zn along with good care and maintenance of roofs are critical in reducing Zn pollution in roof runoff. PMID:15531389

  1. Effects of roof and rainwater characteristics on copper concentrations in roof runoff.

    PubMed

    Bielmyer, Gretchen K; Arnold, W Ray; Tomasso, Joseph R; Isely, Jeff J; Klaine, Stephen J

    2012-05-01

    Copper sheeting is a common roofing material used in many parts of the world. However, copper dissolved from roof sheeting represents a source of copper ions to watersheds. Researchers have studied and recently developed a simple and efficient model to predict copper runoff rates. Important input parameters include precipitation amount, rain pH, and roof angle. We hypothesized that the length of a roof also positively correlates with copper concentration (thus, runoff rates) on the basis that runoff concentrations should positively correlate with contact time between acidic rain and the copper sheet. In this study, a novel system was designed to test and model the effects of roof length (length of roof from crown to the drip edge) on runoff copper concentrations relative to rain pH and roof angle. The system consisted of a flat-bottom copper trough mounted on an apparatus that allowed run length and slope to be varied. Water of known chemistry was trickled down the trough at a constant rate and sampled at the bottom. Consistent with other studies, as pH of the synthetic rainwater decreased, runoff copper concentrations increased. At all pH values tested, these results indicated that run length was more important in explaining variability in copper concentrations than was the roof slope. The regression equation with log-transformed data (R(2) = 0.873) accounted for slightly more variability than the equation with untransformed data (R(2) = 0.834). In log-transformed data, roof angle was not significant in predicting copper concentrations. PMID:21713491

  2. The wind resistance of asphalt roofing shingles

    NASA Astrophysics Data System (ADS)

    Dixon, Craig Robert

    Asphalt shingle roofing is the leading cause of hurricane wind-related insured losses in residential buildings. Damage statistics generated from recent hurricanes indicate shingle roofs sustain damage in wind velocities below design-level with damage frequency increasing with shingle roof age. The objective of this dissertation is the identification of primary mechanisms triggering the failure of shingle roof systems in wind. The research goal is to reduce future shingle roof wind damage and improve our ability to predict asphalt shingle wind resistance. Five studies comprising this dissertation addressed the adhesive consistency and strength of aged asphalt shingles, system-level wind resistance, and the load model underpinning the ASTM D7158 wind test standard. The most significant and unexpected finding was partially unsealed shingles on field, hip, and ridge locations on Florida and Texas homes. Location on the shingle's sealant strip where unsealed and failure mode were consistent at each location. Total quantity of partially unsealed shingles in the field of the roof significantly increased with age, aligning with damage statistics. Full-scale wind tunnel tests demonstrate partially unsealed shingles are more vulnerable than fully sealed due to increased distributed force on sealant strip and concentrated force at the adhered and non-adhered interface. Uplift resistance was measured in artificially and naturally aged shingles. For artificially aged shingles, one of three products evaluated had statistically significant decreases in mean uplift resistance as exposure time increased. However, resistance was above design-level at all exposure test intervals. Naturally aged shingles also had resistance above design-level. Combined results demonstrate that reduced uplift capacity can occur, but high initial bond strength promotes long-term uplift resistance. Wind loads exerted on the shingles sealant strip load path were directly measured on fully sealed and partially unsealed three-tab and laminate shingles. Results indicate that ASTM D7158 and load model is conservative in force prediction for fully sealed shingles. ASTM D7158 is not conservative for partially unsealed shingles. Research concludes that partially unsealed shingles occur naturally and represent a large contributor to wind damage. Retrofit of existing shingle roofs and further work identifying specific cause will provide significant reduction of wind risk in shingle roofing.

  3. An operational integrated short-term warning solution for solar radiation storms: introducing the Forecasting Solar Particle Events and Flares (FORSPEF) system

    NASA Astrophysics Data System (ADS)

    Anastasiadis, Anastasios; Sandberg, Ingmar; Papaioannou, Athanasios; Georgoulis, Manolis; Tziotziou, Kostas; Jiggens, Piers; Hilgers, Alain

    2015-04-01

    We present a novel integrated prediction system, of both solar flares and solar energetic particle (SEP) events, which is in place to provide short-term warnings for hazardous solar radiation storms. FORSPEF system provides forecasting of solar eruptive events, such as solar flares with a projection to coronal mass ejections (CMEs) (occurrence and velocity) and the likelihood of occurrence of a SEP event. It also provides nowcasting of SEP events based on actual solar flare and CME near real-time alerts, as well as SEP characteristics (peak flux, fluence, rise time, duration) per parent solar event. The prediction of solar flares relies on a morphological method which is based on the sophisticated derivation of the effective connected magnetic field strength (Beff) of potentially flaring active-region (AR) magnetic configurations and it utilizes analysis of a large number of AR magnetograms. For the prediction of SEP events a new reductive statistical method has been implemented based on a newly constructed database of solar flares, CMEs and SEP events that covers a large time span from 1984-2013. The method is based on flare location (longitude), flare size (maximum soft X-ray intensity), and the occurrence (or not) of a CME. Warnings are issued for all > C1.0 soft X-ray flares. The warning time in the forecasting scheme extends to 24 hours with a refresh rate of 3 hours while the respective warning time for the nowcasting scheme depends on the availability of the near real-time data and falls between 15-20 minutes. We discuss the modules of the FORSPEF system, their interconnection and the operational set up. The dual approach in the development of FORPSEF (i.e. forecasting and nowcasting scheme) permits the refinement of predictions upon the availability of new data that characterize changes on the Sun and the interplanetary space, while the combined usage of solar flare and SEP forecasting methods upgrades FORSPEF to an integrated forecasting solution. This work has been funded through the "FORSPEF: FORecasting Solar Particle Events and Flares", ESA Contract No. 4000109641/13/NL/AK

  4. Monitoring roof beam lateral displacement at the Waste Isolation Pilot Plant

    SciTech Connect

    Terrill, L.J.; Lewis, R.E.

    1996-12-01

    Lateral displacement in the immediate roof beam at the Waste Isolation Pilot Plant (WIPP) is a significant factor in assessment of excavation performance for the design of ground control systems. Information on roof beam lateral displacement, expansion, fracture formation, as well as excavation convergence, is gathered using a variety of manually and remotely read instruments. Visual observations are also used when possible. This paper describes the methods used to measure lateral displacement, or offset, at the WIPP. Offset magnitudes are determined by the degree of occlusion in drillholes that intersect the offset plane. The Borehole Lateral Displacement Sensor (BLDS) was developed for installation at WIPP to monitor offset at a high degree of accuracy at a short reading frequency. Offset measurements have historically been obtained by visual estimation of borehole conclusion. Use of the BLDS will enable relationships between time dependent roof beam lateral displacement and expansion to be established in much shorter periods than is possible using visual observations. The instrument will also allow remote monitoring of roof beam displacement in areas where visual estimations are not possible. Continued monitoring of roof beam displacement, convergence, and expansion, is integral to timely and pertinent assessments of WIPP excavation performance.

  5. Monitoring roof beam lateral displacement at the waste isolation pilot plant

    SciTech Connect

    Terrill, L.J.; Lewis, R.E.

    1996-08-01

    Lateral displacement in the immediate roof beam at the Waste Isolation Pilot Plant (WIPP) is a significant factor in assessment of excavation performance for the design of ground control systems. Information on roof beam lateral displacement, expansion, fracture formation, as well as excavation convergence, is gathered using a variety of manually and remotely read instruments. Visual observations are also used when possible. This paper describes the methods used to measure lateral displacement, or offset, at the WIPP. Offset magnitudes are determined by the degree of occlusion in drillholes that intersect the offset plane. The Borehole Lateral Displacement Sensor (BLDS) was developed for installation at WIPP to monitor offset at a high degree of accuracy at a short reading frequency. Offset measurements have historically been obtained by visual estimation of borehole occlusion. Use of the BLDS will enable relationships between time dependent roof beam lateral displacement and expansion to be established in much shorter periods than is possible using visual observations. The instrument will also allow remote monitoring of roof beam displacement in areas where visual estimations are not possible. Continued monitoring of roof beam displacement, convergence, and expansion, is integral to timely and pertinent assessments of WIPP excavation performance.

  6. 15. DETAIL OF UNDERSIDE OF ROOF OF EAST PRIVY, SHOWING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. DETAIL OF UNDERSIDE OF ROOF OF EAST PRIVY, SHOWING FINIAL BASE AND RADIAL JOISTS, WITH SCALE; REVEALS ROOF SHEATHING CONFIGURATION (1987) - Poplar Forest, Privies, State Route 661, Forest, Bedford County, VA

  7. Predicting moisture problems in low-slope roofing

    SciTech Connect

    Desjarlais, A.O.; Byars, N.A.

    1998-11-01

    Moisture intrusion is the major reason why low-slope roofing systems fail prematurely. With approximately 75% of all roofing activity being reroofing, the roofing professional is faced with deciding what to do with an existing wet roof on almost a daily basis. This paper describes finite-difference computer modeling that has been performed to address moisture control in low-slope roof systems. Based on a large database of finite difference modeling results, algorithms have been developed that allow the roofing practitioners to simply determine if a roofing system design requires a vapor retarder or if the system can be modified to enhance its tolerance for small leaks. This paper illustrates how modeling results were obtained, describes the process employed to develop the algorithms, and demonstrates how these algorithms can be used to design a moisture tolerant low-slope roof. The range of applicability and limitations of these algorithms is also detailed.

  8. 46. OCTAGONAL & WEST TOWERS FROM SOUTH TOWER ROOF, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    46. OCTAGONAL & WEST TOWERS FROM SOUTH TOWER ROOF, LOOKING NORTHWEST, WITH WEST WING ROOF - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  9. 42. SOUTHEAST TOWER & EAST WING ROOF FROM SOUTH TOWER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    42. SOUTHEAST TOWER & EAST WING ROOF FROM SOUTH TOWER ROOF, LOOKING EAST BY NORTHEAST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  10. Interior view of the Sheet Metal Shop showing the roof ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view of the Sheet Metal Shop showing the roof trusses and corrugated metal roof covering, view facing northwest - Kahului Cannery, Plant No. 28, Boiler House, Sheet Metal and Electrical Shops, 120 Kane Street, Kahului, Maui County, HI

  11. Thermoplastic Single-Ply Roof Relieves Water Damage and Inconvenience.

    ERIC Educational Resources Information Center

    Williams, Jennifer Lynn

    2002-01-01

    Assesses use of thermoplastic single-ply roofs by North Carolina's Mars Hill College to prevent leaks, reduce maintenance costs, and enhance the value of their older historic buildings. Administrators comment on the roof's installation efficiency and cleanliness. (GR)

  12. 5. ROOF DETAIL, LOOKING EAST TOWARD SECOND FLOOR WAREHOUSE FROM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. ROOF DETAIL, LOOKING EAST TOWARD SECOND FLOOR WAREHOUSE FROM ROOF OF ASSEMBLY AREA. - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

  13. The Integrated Science Investigation of the Sun (ISIS): Energetic Particle Measurements for the Solar Probe Plus Mission

    NASA Technical Reports Server (NTRS)

    McComas, D. J.; Christian, E. R.; Wiedenbeck, M. E.; McNutt, R. L.; Cummings, A. C.; Desai, M. I.; Giacalone, J.; Hill, M. E.; Mewaldt, R. A.; Krimigis, SA. M.; Livi, S. A.; Mitchell, D. G.; Matthaeus, W. H.; Roelof, E. C.; Stone, E. C.; Schwardron, N. A.; vonRosenvinge, T. T.

    2011-01-01

    One of the major goals of NASA's Solar Probe Plus (SPP) mission is to determine the mechanisms that accelerate and transport high-energy particles from the solar atmosphere out into the heliosphere. Processes such as coronal mass ejections and solar flares, which peak roughly every 11 years around solar maximum, release huge quantities of energized matter, magnetic fields and electromagnetic radiation into space. The high-energy particles, known as solar energetic particles or SEPs, present a serious radiation threat to human explorers living and working outside low-Earth orbit and to technological assets such as communications and scientific satellites in space. This talk describes the Integrated Science Investigation of the Sun (ISIS) - Energetic Particle Instrument suite. ISIS measures key properties such as intensities, energy spectra, composition, and angular distributions of the low-energy suprathermal source populations, as well as the more hazardous, higher energy particles ejected from the Sun. By making the first-ever direct measurements of the near-Sun regions where the acceleration takes place, ISIS will provide the critical measurements that, when integrated with other SPP instruments and with solar and interplanetary observations, will lead to a revolutionary new understanding of the Sun and major drivers of solar system space weather.

  14. The Integrated Science Investigation of the Sun (ISIS): Energetic Particle Measurements for the Solar Probe Plus Mission

    NASA Astrophysics Data System (ADS)

    Scherrer, J.; McComas, D. J.; Christian, E. R.; Cummings, A. C.; Desai, M. I.; Giacalone, J.; Hill, M. E.; Krimigis, S. M.; Livi, S. A.; McNutt, R. L.; Mewaldt, R. A.; Mitchell, D. G.; Matthaeus, W. H.; Roelof, E. C.; von Rosenvinge, T. T.; Schwadron, N. A.; Stone, E. C.; Velli, M. M.; Wiedenbeck, M. E.

    2010-12-01

    One of the major goals of NASA’s Solar Probe Plus (SPP) mission is to determine the mechanisms that accelerate and transport high-energy particles from the solar atmosphere out into the heliosphere. During the height of solar activity, which occurs roughly once every 11 years, processes such as coronal mass ejections and solar flares release huge quantities of energized matter, magnetic fields and electromagnetic radiation into space. These high-energy particles, known as solar energetic particles or SEPs, present a serious radiation threat to human explorers living and working outside low-Earth orbit and to technological assets such as communications and scientific satellites in space. This talk describes the Integrated Science Investigation of the Sun (ISIS) - Energetic Particle Instrument suite. ISIS measures key properties such as intensities, energy spectra, composition, and angular distributions of the low-energy suprathermal source populations, as well as the more hazardous, higher energy particles ejected from the Sun. By making the first-ever direct measurements of the near-Sun regions where the acceleration takes place, ISIS will provide the critical measurements that, when integrated with other SPP instruments and with solar and interplanetary observations, will lead to a much deeper understanding of the Sun and major drivers of solar system space weather.

  15. Passive solar design handbook

    NASA Astrophysics Data System (ADS)

    Baker, M. S.

    1985-04-01

    A basic introduction to solar energy is provided in this manual. The most common passive solar heating designs are described very briefly. The designs presented fall under three passive heating classifications: direct gain, indirect gain, and isolated gain. Design considerations for buildings are included along with considerations for: thermal storage walls, thermal storage roofs, attached sunspaces, and convectiv loops. A glossary of solar energy related terms is included.

  16. A novel technique for the production of cool colored concrete tile and asphalt shingle roofing products

    SciTech Connect

    Levinson, Ronnen; Akbari, Hashem; Berdahl, Paul; Wood, Kurt; Skilton, Wayne; Petersheim, Jerry

    2009-11-20

    The widespread use of solar-reflective roofing materials can save energy, mitigate urban heat islands and slow global warming by cooling the roughly 20% of the urban surface that is roofed. In this study we created prototype solar-reflective nonwhite concrete tile and asphalt shingle roofing materials using a two-layer spray coating process intended to maximize both solar reflectance and factory-line throughput. Each layer is a thin, quick-drying, pigmented latex paint based on either acrylic or a poly(vinylidene fluoride)/acrylic blend. The first layer is a titanium dioxide rutile white basecoat that increases the solar reflectance of a gray-cement concrete tile from 0.18 to 0.79, and that of a shingle surfaced with bare granules from 0.06 to 0.62. The second layer is a 'cool' color topcoat with weak near-infrared (NIR) absorption and/or strong NIR backscattering. Each layer dries within seconds, potentially allowing a factory line to pass first under the white spray, then under the color spray. We combined a white basecoat with monocolor topcoats in various shades of red, brown, green and blue to prepare 24 cool color prototype tiles and 24 cool color prototypes shingles. The solar reflectances of the tiles ranged from 0.26 (dark brown; CIELAB lightness value L* = 29) to 0.57 (light green; L* = 76); those of the shingles ranged from 0.18 (dark brown; L* = 26) to 0.34 (light green; L* = 68). Over half of the tiles had a solar reflectance of at least 0.40, and over half of the shingles had a solar reflectance of at least 0.25.

  17. 40 CFR 1037.140 - Curb weight and roof height.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 34 2013-07-01 2013-07-01 false Curb weight and roof height. 1037.140... Requirements § 1037.140 Curb weight and roof height. (a) Where applicable, a vehicle's curb weight and roof height are determined from nominal design specifications, as provided in this section. Round the...

  18. 40 CFR 1037.140 - Curb weight and roof height.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Curb weight and roof height. 1037.140... Requirements § 1037.140 Curb weight and roof height. (a) Where applicable, a vehicle's curb weight and roof height are determined from nominal design specifications, as provided in this section. Round the...

  19. 40 CFR 1037.140 - Curb weight and roof height.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Curb weight and roof height. 1037.140... Requirements § 1037.140 Curb weight and roof height. (a) Where applicable, a vehicle's curb weight and roof height are determined from nominal design specifications, as provided in this section. Round the...

  20. 49 CFR 238.441 - Emergency roof access.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Emergency roof access. 238.441 Section 238.441... Equipment § 238.441 Emergency roof access. (a) Existing passenger cars and power cars. Each passenger car..., 2011, shall have a minimum of one roof hatch emergency access location with a minimum opening of...

  1. 49 CFR 238.123 - Emergency roof access.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... conspicuously marked structural weak point in the roof for access by properly equipped emergency response.... If emergency roof access is provided by means of a structural weak point— (1) The retroreflective... 49 Transportation 4 2010-10-01 2010-10-01 false Emergency roof access. 238.123 Section...

  2. 40 CFR 63.1063 - Floating roof requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... subpart, whichever occurs first. (ii) External floating roof. An EFR shall be equipped with one of the... degassed, or every 5 years, whichever occurs first. (2) External floating roofs. External floating roofs...) The length of each gap shall be determined by inserting the probe into the gap (vertically)...

  3. Introduction to Roofing. Instructor Edition. Introduction to Construction Series.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This instructor's guide contains the materials required to teach a competency-based introductory course in roofing to students who have chosen to explore careers in construction. The following topics are covered in the course's three instructional units: roofing materials, roofing tools, and applied skills. Each unit contains some or all of the…

  4. You're a What? Solar Photovoltaic Installer

    ERIC Educational Resources Information Center

    Torpey, Elka Maria

    2009-01-01

    This article talks about solar photovoltaic (PV) installer and features Rebekah Hren, a solar PV installer who puts solar panels on roofs and in other sunny places to turn the sun's power into electricity. Hren enjoys promoting renewable energy, in part because it's an emerging field. In solar PV systems, solar cells--devices that convert sunlight…

  5. Roofing with Urethane: Pro and Con.

    ERIC Educational Resources Information Center

    Kinzer, Michael; Scott, Gerald P.E.

    1981-01-01

    Gerald Scott's favorable evaluation of the foamed polyurethane roofing system is based on experiences with 55 buildings at Texas A & M. Michael Kinzer, an architect at Colorado State University, disagrees and claims that the system is difficult to install and maintain, and the cost prohibitive. (MLF)

  6. Thrust bolting: roof bolt support apparatus

    SciTech Connect

    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.

  7. Accidents due to falls from roof slabs.

    PubMed

    Rudelli, Bruno Alves; Silva, Marcelo Valerio Alabarce da; Akkari, Miguel; Santili, Claudio

    2013-01-01

    CONTEXT AND OBJECTIVE Falls from the roof slabs of houses are accidents of high potential severity that occur in large Brazilian cities and often affect children and adolescents. The aims of this study were to characterize the factors that predispose towards this type of fall involving children and adolescents, quantify the severity of associated lesions and suggest preventive measures. DESIGN AND SETTING Descriptive observational prospective longitudinal study in two hospitals in the metropolitan region of São Paulo. METHODS Data were collected from 29 cases of falls from roof slabs involving children and adolescents between October 2008 and October 2009. RESULTS Cases involving males were more prevalent, accounting for 84%. The predominant age group was schoolchildren (7 to 12 years old; 44%). Leisure activities were most frequently being practiced on the roof slab at the time of the fall (86%), and flying a kite was the most prevalent game (37.9%). In 72% of the cases, the children were unaccompanied by an adult responsible for them. Severe conditions such as multiple trauma and traumatic brain injuries resulted from 79% of the accidents. CONCLUSION Falls from roof slabs are accidents of high potential severity, and preventive measures aimed towards informing parents and guardians about the dangers and risk factors associated with this type of accident are needed, along with physical protective measures, such as low walls around the slab and gates with locks to restrict free access to these places. PMID:23903263

  8. Roof Shield for Advance and Retreat Mining

    NASA Technical Reports Server (NTRS)

    Lewis, E. V.

    1985-01-01

    Shield sections change their configuration to suit mining mode. Articulation cylinders raise rear shield to advance position, and locking cylinders hold it there. To change to retreat position articulation cylinders lower shield. Locking pins at edge of outermost shield plate latch shield to chock base. Shield accommodates roof heights ranging from 36 to 60 inches (0.9 to 1.52 meters).

  9. The Potential of Roof Deck Play Spaces.

    ERIC Educational Resources Information Center

    Canada Mortgage and Housing Corp., Ottawa (Ontario).

    This report, the fifteenth in a series of twenty completed by the Children's Environments Advisory Service for the International Year of the Child, 1979, presents a guide for planning play spaces on roof decks in high density family housing projects where on-grade land is too scarce or too expensive for development as communal recreation space.…

  10. An innovative system for heating and cooling a gymnasium using integrated photovoltaic-thermal solar collectors

    SciTech Connect

    Fanchiotti, A.; Herkel, S.; Laukamp, H.; Priolo, C.

    1996-11-01

    The paper describes a new solar energy based system to heat and cool a gymnasium and to generate electricity in the city of Palermo, Italy. The gymnasium will be built in 1996 as part of the structures that will host the Universiadi Games in 1997. Main objectives of the project are: (a) to grant better environmental conditions in the area occupied by the public, with limited use of fossil energy; (b) to reduce the temperature of the photovoltaic elements, thus increasing their efficiency. The system consists of an array of 203 m{sup 2} integrated photovoltaic-thermal solar air collectors. In the winter mode of operation, the heated air is passed through the concrete benches where the public is seated. In the summer mode of operation outside air is evaporatively cooled, passed through the benches, then exhausted to the outside after passing through the collectors. The paper presents some of the results obtained by simulating the system at the design stage for winter conditions.

  11. Space Solar Power Multi-body Dynamics and Controls, Concepts for the Integrated Symmetrical Concentrator Configuration

    NASA Technical Reports Server (NTRS)

    Glaese, John R.; McDonald, Emmett J.

    2000-01-01

    Orbiting space solar power systems are currently being investigated for possible flight in the time frame of 2015-2020 and later. Such space solar power (SSP) satellites are required to be extremely large in order to make practical the process of collection, conversion to microwave radiation, and reconversion to electrical power at earth stations or at remote locations in space. These large structures are expected to be very flexible presenting unique problems associated with their dynamics and control. The purpose of this project is to apply the expanded TREETOPS multi-body dynamics analysis computer simulation program (with expanded capabilities developed in the previous activity) to investigate the control problems associated with the integrated symmetrical concentrator (ISC) conceptual SSP system. SSP satellites are, as noted, large orbital systems having many bodies (perhaps hundreds) with flexible arrays operating in an orbiting environment where the non-uniform gravitational forces may be the major load producers on the structure so that a high fidelity gravity model is required. The current activity arises from our NRA8-23 SERT proposal. Funding, as a supplemental selection, has been provided by NASA with reduced scope from that originally proposed.

  12. Solar Flare Kernel Observations with Integral Field Spectroscopy in H-alpha Line and SDO

    NASA Astrophysics Data System (ADS)

    Suematsu, Y.

    2013-12-01

    We developed a field integral spectroscopic instrument using a micro-lens array at the Domeless Solar Telescope, Hida Obervatory. and obtained data of H-alpha flares in X-ray C- and M-class flares taking place on 3 Nov 2011. The field of view was about 10 arc seconds square and time cadence was 12 seconds. The data demonstrate that simultaneous spectroscopic observations over extended solar structures, at a high spatial resolution and temporal cadence, are important to track and understand the physics of transient phenomena happening in impulsive flare kernels. With two-dimensional field spectral data, we made monochromatic images at given wavelengths in the H-alpha line and nearby continuum to co-align with X-ray and UV images from SDO. We also carried out line profile analysis to derive 2-D distribution of atmospheric parameters. Obtained H-alpha spectra clearly show the rapid development of red asymmetry at the flare kernels, giving a large downward Doppler shift of up to 50 km/sec. The accompanied formation of coronal flaring loop structures are consistent with a scenario of downward motion of compressed chromospheric flare kernels due do impulsive heat flow from the corona to the chromosphere and simultaneous evaporation of the chromospheric material into the corona.

  13. TASK 2.5.7 FIELD EXPERIMENTS TO EVALUATE COOL-COLORED ROOFING

    SciTech Connect

    Miller, William A; Cherry, Nigel J; Allen, Richard Lowell; Childs, Phillip W; Atchley, Jerald Allen; Ronnen, Levinson; Akbari, Hashem; Berhahl, Paul

    2010-03-01

    Aesthetically pleasing dark roofs can be formulated to reflect like a highly reflective white roof in the near infrared portion of the solar spectrum. New paint pigments increase the near infrared reflectance of exterior finishes by minimizing the absorption of near-infrared radiation (NIR). The boost in the NIR reflectance drops the surface temperatures of roofs and walls, which in turn reduces cooling-energy use and provides savings for the homeowner and relief for the utilities. In moderate and hot climates, a roof surface with high solar reflectance and high thermal emittance was shown by Akbari et al. (2004) and by Parker and Sherwin (1998) to reduce the exterior temperature and produce savings in comfort cooling. The new cool color pigments can potentially reduce emissions of carbon dioxide, which in turn reduces metropolitan heat buildup and urban smog. The pigments can also help conserve water resources otherwise used to clean and process fuel consumed by fossil-fuel driven power plants. Cool roofs also result in a lower ambient temperature that further decreases the need for air conditioning, retards smog formation, and improves thermal comfort. Parker, Sonne and Sherwin (2002) demonstrated that white barrel and white flat tiles reduced cooling energy consumption by 22% of the base load used by an adjacent and identical home having direct nailed dark shingles. Part of the savings was due to the reflectance of the white tiles; however, another part was due to the mass of the tile and to the venting occurring within the double batten installation. With, Cherry and Haig (2009) have studied the influence of the thermal mass and batten space ventilation and have found that, referenced to an asphalt shingle system, it can be equivalent to an additional 28 points of solar reflectivity. The double batten arrangement has wooden counter battens laid vertically (soffit-to-ridge) against the roof deck, and then the conventional battens are laid horizontally across the counter battens, providing a nailing surface for the concrete tile. This double batten construction forms an inclined air channel running from the soffit to the ridge. The bottom surface of the channel is formed by the roof decking and is relatively flat and smooth. The top surface is created by the underside of the roofing tiles, and is designed to be an air permeable covering to alleviate the underside air pressure and minimize wind uplift on the tiles. The resulting air flows also have a cooling influence which further complicates prediction of the heat penetrating through the deck because an accurate measure of the airflow is required to predict the heat transfer. Measured temperatures and heat flows at the roof surface, within the attic and at the ceiling of the houses are discussed as well as the power usage to help gauge the benefit of cool-pigmented reflective roof products fitted with and without ventilation above the roof deck. Ventilation occurring above the deck is an inherent feature for tile roof assemblies, and is formed by an air space between the exterior face of the roof sheathing and the underside of the tile. The greater the tile s profile the greater is the effect of the ventilation which herein is termed above-sheathing ventilation (ASV). However, because of the complexity of the thermally induced flow, little credit is allowed by state and federal building codes. ASHRAE (2005) provides empirical data for the effective thermal resistance of plane air spaces. A -in. (0.0191-m) plane air space inclined at 45 with the horizontal has an RUS-0.85 (RSI-0.15) . Our intent is to help further deploy cool color pigments in roofs by conducting field experiments to evaluate the new cool-colored roofing materials in the hot climate of Southern California. The collected data will be used to showcase and market the performance of new cool-roof products and also to help formulate and validate computer codes capable of calculating the heat transfer occurring within the attic and the whole building. Field measures and computer predictions showed that the demonstration home without a NIR-reflective tile coating and without above-sheathing ventilation had the greatest roof deck heat flow and subsequently the highest electrical usage. The house with both NIR paint pigments on the tile and with ASV had the least deck heat flows and therefore caused the home to consume the least amount of energy. The relative performance of the reflective coating and the ventilation individually is less obvious, but it is clear that the combination of a reflective tile with ASV is the preferred solution for the best energy saving.

  14. Efficient inverted polymer solar cells integrated with a compound electron extraction layer

    NASA Astrophysics Data System (ADS)

    Ma, Zhong-Sheng; Wang, Qian-Kun; Li, Chi; Li, Yan-Qing; Zhang, Dan-Dan; Liu, Weimin; Wang, Pengfei; Tang, Jian-Xin

    2015-12-01

    We constructed an effective electron extraction layer (EEL) used for polymer solar cells by integrating one new kind of organic material of 4,4‧-(1,4-phenylene) bis(2-phenyl-6-p-tolylnicotinonitrile) (p-PPtNT) and cesium carbonate (Cs2CO3) used as a compound EEL (CEEL). The CEEL based device exhibits an ideal PCE of 4.15%, corresponding to an enhancement 220% in contrast to that of control device without EEL, which is also comparable to that of ZnO based device. Our analyses indicated that the remarkably improved PCE for CEEL based device is mainly ascribed to the Ohmic contact and the negligible electron extraction barrier at cathode/active layer by inserting CEEL.

  15. Status of cool roof standards in the United States

    SciTech Connect

    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. DYNAMIC STABILITY OF THE SOLAR SYSTEM: STATISTICALLY INCONCLUSIVE RESULTS FROM ENSEMBLE INTEGRATIONS

    SciTech Connect

    Zeebe, Richard E.

    2015-01-01

    Due to the chaotic nature of the solar system, the question of its long-term stability can only be answered in a statistical sense, for instance, based on numerical ensemble integrations of nearby orbits. Destabilization of the inner planets, leading to close encounters and/or collisions can be initiated through a large increase in Mercury's eccentricity, with a currently assumed likelihood of ∼1%. However, little is known at present about the robustness of this number. Here I report ensemble integrations of the full equations of motion of the eight planets and Pluto over 5 Gyr, including contributions from general relativity. The results show that different numerical algorithms lead to statistically different results for the evolution of Mercury's eccentricity (e{sub M}). For instance, starting at present initial conditions (e{sub M}≃0.21), Mercury's maximum eccentricity achieved over 5 Gyr is, on average, significantly higher in symplectic ensemble integrations using heliocentric rather than Jacobi coordinates and stricter error control. In contrast, starting at a possible future configuration (e{sub M}≃0.53), Mercury's maximum eccentricity achieved over the subsequent 500 Myr is, on average, significantly lower using heliocentric rather than Jacobi coordinates. For example, the probability for e{sub M} to increase beyond 0.53 over 500 Myr is >90% (Jacobi) versus only 40%-55% (heliocentric). This poses a dilemma because the physical evolution of the real system—and its probabilistic behavior—cannot depend on the coordinate system or the numerical algorithm chosen to describe it. Some tests of the numerical algorithms suggest that symplectic integrators using heliocentric coordinates underestimate the odds for destabilization of Mercury's orbit at high initial e{sub M}.

  17. Integrated energy, economic, and environmental assessment for the optimal solar absorption cooling and heating system

    NASA Astrophysics Data System (ADS)

    Hang, Yin

    Buildings in the United States are responsible for 41% of the primary energy use and 30% of carbon dioxide emissions. Due to mounting concerns about climate change and resource depletion, meeting building heating and cooling demand with renewable energy has attracted increasing attention in the energy system design of green buildings. One of these approaches, the solar absorption cooling and heating (SACH) technology can be a key solution to addressing the energy and environmental challenges. SACH system is an integration of solar thermal heating system and solar thermal driven absorption cooling system. So far, SACH systems still remain at the demonstration and testing stage due to not only its high cost but also complicated system characteristics. This research aims to develop a methodology to evaluate the life cycle energy, economic and environmental performance of SACH systems by high-fidelity simulations validated by experimental data. The developed methodology can be used to assist the system design. In order to achieve this goal, the study includes four objectives as follows: * Objective 1: Develop the evaluation model for the SACH system. The model includes three aspects: energy, economy, and environment from a life cycle point of view. * Objective 2: Validate the energy system model by solar experiments performance data. * Objective 3: Develop a fast and effective multi-objective optimization methodology to find the optimal system configuration which achieves the maximum system benefits on energy, economy and environment. Statistic techniques are explored to reveal the relations between the system key parameters and the three evaluation targets. The Pareto front is generated by solving this multi-objective optimization problem. * Objective 4: Apply the developed assessment methodology to different building types and locations. Furthermore, this study considered the influence of the input uncertainties on the overall system performance. The sensitivity analysis was performed firstly to identify the most sensitive inputs to the model outputs, and then the Monte Carlo simulation method was applied to perform the uncertainty analysis of these sensitive inputs according to the effect of range and shape of their probability density function. The optimization method developed before was extended to incorporate inputs uncertainties. The research would have great significance for the development of sustainable buildings. The assessment method could be used directly to identify the opportunities for reducing the negative environmental impacts related to buildings. The optimization methodology developed is fast, efficient and easy for implementation. The trends discovered from various building types and climate patterns will become useful guidelines for designers and other professionals.

  18. A New Ground-Based Network for Synoptic Solar Observations: The Solar Physics Research Integrated Network Group (SPRING)

    NASA Astrophysics Data System (ADS)

    Hill, Frank; Roth, Markus; Thompson, Michael; Gusain, Sanjay

    2014-06-01

    SPRING is a project to develop a geographically distributed network of instrumentation to obtain synoptic solar observations. Building on the demonstrated success of networks to provide nearly-continuous long-term data for helioseismology, SPRING will provide data for a wide range of solar research areas. Scientific objectives include internal solar dynamics and structure; wave transport in the solar atmosphere; the evolution of the magnetic field over the activity cycle; irradiance fluctuations; and space weather origins. Anticipated data products include simultaneous full-disk multi-wavelength Doppler and vector magnetic field images; filtergrams in H-Alpha, CaK, and white light; and PSPT-type irradiance support. The data will be obtained with a duty cycle of around 90% and at a cadence no slower than one minute. The current concept is a multi-instrument platform installed in at least six locations, and which will also provide context information for large-aperture solar telescopes such as EST and the DKIST. There is wide support for the idea within the EU and the US solar research communities. The project is in the early planning stages, and we are open to and looking for participants in the science and instrument definition.

  19. Green roofs as a means of pollution abatement.

    PubMed

    Rowe, D Bradley

    2011-01-01

    Green roofs involve growing vegetation on rooftops and are one tool that can help mitigate the negative effects of pollution. This review encompasses published research to date on how green roofs can help mitigate pollution, how green roof materials influence the magnitude of these benefits, and suggests future research directions. The discussion concentrates on how green roofs influence air pollution, carbon dioxide emissions, carbon sequestration, longevity of roofing membranes that result in fewer roofing materials in landfills, water quality of stormwater runoff, and noise pollution. Suggestions for future directions for research include plant selection, development of improved growing substrates, urban rooftop agriculture, water quality of runoff, supplemental irrigation, the use of grey water, air pollution, carbon sequestration, effects on human health, combining green roofs with complementary related technologies, and economics and policy issues. PMID:21074914

  20. DESIGN AND IMPLEMENTATION OF A NOVEL ARCHITECTURE FOR AN INTEGRATED SOLAR THERMAL-BIOGAS CO-GENERATION SYSTEM

    EPA Science Inventory

    The immediate goal is a system based on the integration of the suite of modules developed solar thermal, biogas, ORC, absorption-chiller) that can be assembled together to create systems tailored to the unique demands of individual communities and climates, optimized for effic...

  1. An Integrated Approach to Modeling Solar Electric Propulsion Vehicles During Long Duration, Near-Earth Orbit Transfers

    NASA Technical Reports Server (NTRS)

    Smith, David A.; Hojnicki, Jeffrey S.; Sjauw, Waldy K.

    2014-01-01

    Recent NASA interest in utilizing solar electronic propulsion (SEP) technology to transfer payloads, e.g. from low-Earth orbit (LEO) to higher energy geostationary-Earth orbit (GEO) or to Earth escape, has necessitated the development of high fidelity SEP vehicle models and simulations. These models and simulations need to be capable of capturing vehicle dynamics and sub-system interactions experienced during the transfer trajectories which are typically accomplished with continuous-burn (potentially interrupted by solar eclipse), long duration "spiral out" maneuvers taking several months or more to complete. This paper presents details of an integrated simulation approach achieved by combining a high fidelity vehicle simulation code with a detailed solar array model. The combined simulation tool gives researchers the functionality to study the integrated effects of various vehicle sub-systems (e.g. vehicle guidance, navigation and control (GN&C), electric propulsion system (EP)) with time varying power production. Results from a simulation model of a vehicle with a 50 kW class SEP system using the integrated tool are presented and compared to the results from another simulation model employing a 50 kW end-of-life (EOL) fixed power level assumption. These models simulate a vehicle under three degree of freedom dynamics (i.e. translational dynamics only) and include the effects of a targeting guidance algorithm (providing a "near optimal" transfer) during a LEO to near Earth escape (C (sub 3) = -2.0 km (sup 2) / sec (sup -2) spiral trajectory. The presented results include the impact of the fully integrated, time-varying solar array model (e.g. cumulative array degradation from traversing the Van Allen belts, impact of solar eclipses on the vehicle and the related temperature responses in the solar arrays due to operating in the Earth's thermal environment, high fidelity array power module, etc.); these are used to assess the impact on vehicle performance (i.e. propellant consumption) and transit times.

  2. Flat-plate solar array project. Volume 8: Project analysis and integration

    NASA Technical Reports Server (NTRS)

    Mcguire, P.; Henry, P.

    1986-01-01

    Project Analysis and Integration (PA&I) performed planning and integration activities to support management of the various Flat-Plate Solar Array (FSA) Project R&D activities. Technical and economic goals were established by PA&I for each R&D task within the project to coordinate the thrust toward the National Photovoltaic Program goals. A sophisticated computer modeling capability was developed to assess technical progress toward meeting the economic goals. These models included a manufacturing facility simulation, a photovoltaic power station simulation and a decision aid model incorporating uncertainty. This family of analysis tools was used to track the progress of the technology and to explore the effects of alternative technical paths. Numerous studies conducted by PA&I signaled the achievement of milestones or were the foundation of major FSA project and national program decisions. The most important PA&I activities during the project history are summarized. The PA&I planning function is discussed and how it relates to project direction and important analytical models developed by PA&I for its analytical and assessment activities are reviewed.

  3. TiO2 nanowires for potential facile integration of solar cells and electrochromic devices.

    PubMed

    Qiang, Pengfei; Chen, Zhongwei; Yang, Peihua; Cai, Xiang; Tan, Shaozao; Liu, Pengyi; Mai, Wenjie

    2013-11-01

    Self-powered systems usually consist of energy-acquisition components, energy-storage components and functional components. The development of nanoscience and nanotechnology has greatly improved the performance of all the components of self-powered systems. However, huge differences in the materials and configurations in the components cause large difficulties for integration and miniaturization of self-powered systems. Design and fabrication of different components in a self-powered system with the same or similar materials/configurations should be able to make the above goal easier. In this work, a proof-of-concept experiment involving an integrated self-powered color-changing system consisting of TiO2 nanowire based sandwich dye-sensitized solar cells (DSSCs) and electrochromic devices (ECDs) is designed and demonstrated. When sunlight illuminates the entire system, the DSSCs generate electrical power and turn the ECD to a darker color, dimming the light; by switching the connection polarity of the DSSCs, the lighter color can be regained, implying the potential application of this self-powered color-changing system for next generation sun glasses and smart windows. PMID:24107414

  4. Flat-plate solar array project. Volume 8: Project analysis and integration

    NASA Astrophysics Data System (ADS)

    McGuire, P.; Henry, P.

    1986-10-01

    Project Analysis and Integration (PA&I) performed planning and integration activities to support management of the various Flat-Plate Solar Array (FSA) Project R&D activities. Technical and economic goals were established by PA&I for each R&D task within the project to coordinate the thrust toward the National Photovoltaic Program goals. A sophisticated computer modeling capability was developed to assess technical progress toward meeting the economic goals. These models included a manufacturing facility simulation, a photovoltaic power station simulation and a decision aid model incorporating uncertainty. This family of analysis tools was used to track the progress of the technology and to explore the effects of alternative technical paths. Numerous studies conducted by PA&I signaled the achievement of milestones or were the foundation of major FSA project and national program decisions. The most important PA&I activities during the project history are summarized. The PA&I planning function is discussed and how it relates to project direction and important analytical models developed by PA&I for its analytical and assessment activities are reviewed.

  5. TiO2 nanowires for potential facile integration of solar cells and electrochromic devices

    NASA Astrophysics Data System (ADS)

    Qiang, Pengfei; Chen, Zhongwei; Yang, Peihua; Cai, Xiang; Tan, Shaozao; Liu, Pengyi; Mai, Wenjie

    2013-11-01

    Self-powered systems usually consist of energy-acquisition components, energy-storage components and functional components. The development of nanoscience and nanotechnology has greatly improved the performance of all the components of self-powered systems. However, huge differences in the materials and configurations in the components cause large difficulties for integration and miniaturization of self-powered systems. Design and fabrication of different components in a self-powered system with the same or similar materials/configurations should be able to make the above goal easier. In this work, a proof-of-concept experiment involving an integrated self-powered color-changing system consisting of TiO2 nanowire based sandwich dye-sensitized solar cells (DSSCs) and electrochromic devices (ECDs) is designed and demonstrated. When sunlight illuminates the entire system, the DSSCs generate electrical power and turn the ECD to a darker color, dimming the light; by switching the connection polarity of the DSSCs, the lighter color can be regained, implying the potential application of this self-powered color-changing system for next generation sun glasses and smart windows.

  6. Integrated mitigation and solar radiation management scenarios under combined climate guardrails

    NASA Astrophysics Data System (ADS)

    Stankoweit, Marius; Schmidt, Hauke; Roshan, Elnaz; Pieper, Patrick; Held, Hermann

    2015-04-01

    In addition to the climate policy options 'mitigation' and 'adaptation' solar radiation management (SRM) has been put on the agenda. As SRM costs are comparably low compared to mitigation costs, including SRM risks in the analysis proves essential. In our contribution we focus on precipitation pattern changes as potential side-effects of SRM and perform an integrated mitigation-SRM-based analysis on the basis of economic welfare optimization, constrained by climate guardrails. We define a tolerable scale of precipitation changes by the anomalies that would have been tolerated under a temperature target. Given that metric and a temperature target, by utilizing the integrated assessment model MIND, we derive the cost reduction, induced by including the additional option of SRM. We show that the cost reduction is a strong function of the fraction of Giorgi regions, for which we require compliance with the newly defined SRM guardrail. Compliance with all Giorgi regions might eliminate most of the economic gain achievable through SRM. The effects of alternative parameterizations of the SRM-precipitation pattern change influence chain are discussed.

  7. Establishing Green Roof Infrastructure Through Environmental Policy Instruments

    NASA Astrophysics Data System (ADS)

    Carter, Timothy; Fowler, Laurie

    2008-07-01

    Traditional construction practices provide little opportunity for environmental remediation to occur in urban areas. As concerns for environmental improvement in urban areas become more prevalent, innovative practices which create ecosystem services and ecologically functional land cover in cities will be in higher demand. Green roofs are a prime example of one of these practices. The past decade has seen the North American green roof industry rapidly expand through international green roof conferences, demonstration sites, case studies, and scientific research. This study evaluates existing international and North American green roof policies at the federal, municipal, and community levels. Green roof policies fall into a number of general categories, including direct and indirect regulation, direct and indirect financial incentives, and funding of demonstration or research projects. Advantages and disadvantages of each category are discussed. Salient features and a list of prompting standards common to successfully implemented green roof strategies are then distilled from these existing policies. By combining these features with data collected from an experimental green roof site in Athens, Georgia, the planning and regulatory framework for widespread green roof infrastructure can be developed. The authors propose policy instruments be multi-faceted and spatially focused, and also propose the following recommendations: (1) Identification of green roof overlay zones with specifications for green roofs built in these zones. This spatial analysis is important for prioritizing areas of the jurisdiction where green roofs will most efficiently function; (2) Offer financial incentives in the form of density credits and stormwater utility fee credits to help overcome the barriers to entry of the new technology; (3) Construct demonstration projects and institutionalize a commitment greening roofs on publicly-owned buildings as an effective way of establishing an educated roofing industry and experienced installers for future green roof construction.

  8. Establishing green roof infrastructure through environmental policy instruments.

    PubMed

    Carter, Timothy; Fowler, Laurie

    2008-07-01

    Traditional construction practices provide little opportunity for environmental remediation to occur in urban areas. As concerns for environmental improvement in urban areas become more prevalent, innovative practices which create ecosystem services and ecologically functional land cover in cities will be in higher demand. Green roofs are a prime example of one of these practices. The past decade has seen the North American green roof industry rapidly expand through international green roof conferences, demonstration sites, case studies, and scientific research. This study evaluates existing international and North American green roof policies at the federal, municipal, and community levels. Green roof policies fall into a number of general categories, including direct and indirect regulation, direct and indirect financial incentives, and funding of demonstration or research projects. Advantages and disadvantages of each category are discussed. Salient features and a list of prompting standards common to successfully implemented green roof strategies are then distilled from these existing policies. By combining these features with data collected from an experimental green roof site in Athens, Georgia, the planning and regulatory framework for widespread green roof infrastructure can be developed. The authors propose policy instruments be multi-faceted and spatially focused, and also propose the following recommendations: (1) Identification of green roof overlay zones with specifications for green roofs built in these zones. This spatial analysis is important for prioritizing areas of the jurisdiction where green roofs will most efficiently function; (2) Offer financial incentives in the form of density credits and stormwater utility fee credits to help overcome the barriers to entry of the new technology; (3) Construct demonstration projects and institutionalize a commitment greening roofs on publicly-owned buildings as an effective way of establishing an educated roofing industry and experienced installers for future green roof construction. PMID:18389306

  9. Solar heating system final design package

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The system is composed of a warm air collector, a logic control unit and a universal switching and transport unit. The collector was originally conceived and designed as an integrated roof/wall system and therefore provides a dual function in the structure. The collector serves both as a solar energy conversion system and as a structural weather resistant skin. The control unit provides totally automatic control over the operation of the system. It receives input data from sensor probes in collectors, storage and living space. The logic was designed so as to make maximum use of solar energy and minimize use of conventional energy. The transport and switching unit is a high-efficiency air-handling system equipped with gear motor valves that respond to outputs from the control system. The fan unit was designed for maximum durability and efficiency in operation, and has permanently lubricated ball bearings and excellent air-handling efficiency.

  10. Bonded Bracket Assmebly for Frameless Solar Panels

    SciTech Connect

    Murray, Todd; Jackson, Nick; Dupont, Luc; Moser, Jeff

    2013-01-30

    In February 2011 the US Department of Energy announced their new Sunshot Initiative. The Sunshot goal is to reduce the total cost of solar energy systems by about 75 percent before the end of the decade. The DOE estimated that a total installed cost of $$1 per watt for photovoltaic systems would be equivalent to 5-6¢/kilowatt hour (kWh) for energy available from the grid. The DOE also estimated that to meet the $1 per watt goal, PV module costs would need to be reduced to $ .50 per watt, balance of systems costs would need to be reduced to $.40 per watt, and power electronic costs would need to reach $.10 per watt. To address the BOS balance of systems cost component of the $1 per watt goal, the DOE announced a funding opportunity called (BOS-X) Extreme Balance of System Hardware Cost Reductions. The DOE identified eight areas within the total BOS costs: 1) installation labor, 2) installation materials, 3) installation overhead and profit, 4) tracker, 5) permitting and commissioning, 6) site preparation, 7) land acquisition, 8) sales tax. The BOS-X funding announcement requested applications in four specific topics;Topic 1: Transformational Building Integrated Photovoltaic (BIPV) Modules; Topic 2: Roof and Ground Mount Innovations; Topic 3: Transformational Photovoltaic System Designs; and Topic 4: Development of New Wind Load Codes for PV Systems.The application submitted by ARaymond Tinnerman reflected the requirements listed in Topic #2, Roof and Ground Mount Innovations. The goal of topic #2 was to develop technologies that would result in the extreme reduction of material and labor costs associated with applications that require physical connections and attachments to roof and ground mount structures. The topics researched in this project included component cost reduction, labor reduction, weight reduction, wiring innovations, and alternative material utilization. The project objectives included; 1) The development of an innovative quick snap bracket assembly that would be bonded to frameless PV modules for commercial rooftop installations; 2) The development of a composite pultruded rail to replace traditional racking materials; 3) In partnership with a roofing company, pilot the certification of a commercial roof to be solar panel compliant, eliminating the need for structural analysis and government oversight resulting in significantly decreased permitting costs; and 4) Reduce the sum of all cost impacts in topic #2 from a baseline total of $2.05/watt to $.34/watt.

  11. The current bases for roof fall prediction at WIPP and a preliminary prediction for SPDV Room 2

    SciTech Connect

    Not Available

    1993-10-01

    This document presents the current bases for roof fall prediction at the Waste Isolation Pilot Plant (WIPP) and a preliminary prediction of the date of a roof fall in SPDV Test Room 2. The ability to correctly assess the stability of the excavations at the WIPP is necessary to protect the safety of site workers, the environment, and the integrity of in situ experiments that use transuranic mixed waste. Roof fall is the extreme case of instability. Although roof falls have been allowed to occur unused, barricaded rooms so that the pre-collapse behavior of this room could be studied. This document presents a discussion of some deformation mechanisms that can be expected around excavations in bedded salt at the WIPP. The geomechanical instrument data and fracture maps from the Site and Preliminary Design Validation (SPDV) room area have been analyzed to determine the deformation history of the rooms and to identify precursors to the SPDV Room 1 roof fall. The deformation history of the excavations as recorded by the instruments was then correlated with these proposed deformation mechanisms, providing a basis for prediction of roof falls in other locations. Finally, the means used at the WIPP to identify and monitor unstable ground are discussed. Throughout this document, ``Room 1 `` and ``Room 2`` refer to SPDV Rooms 1 and 2 unless otherwise stated.

  12. Pv-Thermal Solar Power Assembly

    DOEpatents

    Ansley, Jeffrey H.; Botkin, Jonathan D.; Dinwoodie, Thomas L.

    2001-10-02

    A flexible solar power assembly includes a flexible photovoltaic device attached to a flexible thermal solar collector. The solar power assembly can be rolled up for transport and then unrolled for installation on a surface, such as the roof or side wall of a building or other structure, by use of adhesive and/or other types of fasteners.

  13. Thrust bolting: Roof-bolt-support apparatus

    SciTech Connect

    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.

  14. Reflective "Cool" Roofs Under Aerosol-Burdened Skies: Radiative Benefits Across Selected Indian Cities

    NASA Astrophysics Data System (ADS)

    Millstein, D.; Fischer, M. L.

    2014-12-01

    The use of reflective surfaces offers one low-cost solution for reducing solar loading to urban environments and the Earth that should be considered as part of sustainable urban design. Here, we characterize the radiative benefits, i.e. the additional shortwave radiation leaving the atmosphere, from the installation of highly reflective "cool" roofs in urban areas in India that face relatively large local aerosol burdens. We use a previously tested column radiative transfer model to estimate the energy per unit area reflected to space from increasing the surface albedo at six cities within India. The model is used to characterize radiative transfer each day over five years (2008-2012) based on mid-day satellite retrievals of MODIS aerosol depth, cloud water path, and average surface albedo and MERRA atmospheric profiles of temperature and composition. Compared against 10 months of field observations in two cities, the model derived incoming surface shortwave radiation estimates relative to observations show small biases (0.5% and -2.6%, at Pantnagar and Nainital, respectively). Despite the high levels of local aerosols we found cool roofs provided significant radiative benefits at all locations. Averaged over the five year period we found that increasing the albedo of 1 m-2 of roof area by 0.5 would reflect to space 0.9 - 1.2 kWh daily from 08:30 - 15:30 LST, depending on location. This is equivalent to a constant forcing of 37 - 50 W m-2 (equivalent to reducing CO2 emissions by 74 to 101 kg CO2 m-2 roof area). Last, we identify a co-benefit of improving air quality, in that removing aerosols from the atmosphere could increase the radiative benefits from cool roofs by 23 - 74%, with the largest potential increase found at Delhi and the smallest change found at Nainital.

  15. Reflective ‘cool’ roofs under aerosol-burdened skies: radiative benefits across selected Indian cities

    NASA Astrophysics Data System (ADS)

    Millstein, D. E.; Fischer, M. L.

    2014-10-01

    The use of reflective surfaces offers one low-cost solution for reducing solar loading to urban environments and the Earth that should be considered as part of sustainable urban design. Here, we characterize the radiative benefits, i.e. the additional shortwave radiation leaving the atmosphere, from the installation of highly reflective ‘cool’ roofs in urban areas in India that face relatively large local aerosol burdens. We use a previously tested column radiative transfer model to estimate the energy per unit area reflected to space from increasing the surface albedo at six cities within India. The model is used to characterize radiative transfer each day over five years (2008-2012) based on mid-day satellite retrievals of MODIS aerosol depth, cloud water path, and average surface albedo and MERRA atmospheric profiles of temperature and composition. Compared against ten months of field observations in two cities, the model derived incoming surface shortwave radiation estimates relative to observations show small biases (0.5% and -2.6%, at Pantnagar and Nainital, respectively). Despite the high levels of local aerosols we found cool roofs provided significant radiative benefits at all locations. Averaged over the five year period we found that increasing the albedo of 1 m2 of roof area by 0.5 would reflect to space 0.9-1.2 kWh daily from 08:30-15:30 LST, depending on location. This is equivalent to a constant forcing of 37-50 W m-2 (equivalent to reducing CO2 emissions by 74 to 101 kg CO2 m-2 roof area). Last, we identify a co-benefit of improving air quality, in that removing aerosols from the atmosphere could increase the radiative benefits from cool roofs by 23-74%, with the largest potential increase found at Delhi and the smallest change found at Nainital.

  16. Solar technology assessment project. Volume 4: Solar air conditioning: Active, hybrid and passive

    NASA Astrophysics Data System (ADS)

    Yellott, J. I.

    1981-04-01

    The status of absorption cycle solar air conditioning and the Rankine cycle solar cooling system is reviewed. Vapor jet ejector chillers, solar pond based cooling, and photovoltaic compression air conditioning are also briefly discussed. Hybrid solar cooling by direct and indirect evaporative cooling, and dehumidification by desiccation are described and discussed. Passive solar cooling by convective and radiative processes, evaporative cooling by passive processes, and cooling with roof ponds and movable insulation are reviewed. Federal and state involvement in solar cooling is discussed.

  17. Can wet roof insulation be dried out

    SciTech Connect

    Tobiasson, W.; Korhonen, C.; Coutermarsh, B.; Greatorex, A.

    1983-01-01

    Nondestructive techniques are being widely used to locate wet insulation in compact roofing systems. Now that wet insulation can be found, breather vents and so-called breathable membranes are being promoted to dry out wet insulation, thereby recovering its thermal effectiveness. Exposure tests in New Hampshire indicate that the above venting methods are all rather ineffective in drying sealed specimens of perlite and fibrous glass roof insulation. It would take many decades to dry our specimens at the rates measured over the past two years. Cross-ventilation within the insulation increased the rate of drying. For perlite insulation, the faster rate would still result in a drying time measured in decades. For fibrous glass insulation, the drying time was reduced to 13 years. Fibrous glass insulation in a roof was dried by removing the water with a vacuum cleaner. In a series of tests with a total duration of 134 h, about 0.4 2 m/sup 3/ (110 gal) of water was removed from a 17-m/sup 2/ (180-ft/sup 2/) area of 38-mm (1.5-in.)-thick insulation. Before the water was removed the insulation had only 21% of its dry insulating ability; afterward it had 83%.

  18. Can wet roof insulation be dried out

    SciTech Connect

    Tobiasson, W.; Coutermarsh, B.; Greatorex, A.; Korhonen, C.

    1981-12-01

    Nondestructive techniques are being widely used to locate wet insulation in compact roofing systems. Now that wet insulation can be found, breather vents and so called ''breathable'' membranes are being promoted to dry out wet insulation, thereby recovering its thermal effectiveness. Exposure tests in New Hampshire indicate that the above venting methods are all rather ineffective in drying sealed specimens of perlite and fibrous glass roof insulation. It would take many decades to dry specimens at the rates measured over the past two years. Cross-ventilation within the insulation increased the rate of drying. For perlite insulation, the faster rate would still result in a drying time measured in decades. For fibrous glass insulation, the drying time was reduced to 13 years. The authors have succeeded in drying fibrous glass insulation in a roof by removing the water with a vacuum cleaner. In a series of tests with a total duration of 134 h, about 0.42 m/sup 3/ (110 gal) of water was removed from a 17-m/sup 2/ (180-ft/sup 2/) area of 38-mm (1.5-in.)-thick insulation. Before the water was removed the insulation had only 21 percent of its dry insulating ability; afterward it had 83 percent.

  19. Solar-heating system

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Report describes solar modular domestic-hot-water and space-heating system intended for use in small single family dwelling where roof-mounted collectors are not feasible. Contents include design, performance, and hardware specifications for assembly, installation, operation, and maintenance of system.

  20. Demonstration of energy savings of cool roofs. Executive summary

    SciTech Connect

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

    1998-06-01

    The use of dark roofs affects cooling and heating energy use in buildings and the urban climate. At the building scale, dark roofs are heated by the summer sun and thus raise the summertime air-conditioning (a/c) demand. For highly-absorptive (low-albedo) roofs the difference between the surface and ambient air temperatures may be as high as 90 F on a summer afternoon. While for less absorptive (high-albedo) surfaces with similar insulative properties, such as roofs covered with a white coating, the difference is only about 20 F. For this reason, cool roofs (which absorb little insolation) can be effective in reducing cooling energy use. Earlier studies have suggested that cool roofs incur no additional cost if color changes are incorporated into routine re-roofing and re-surfacing schedules. There is a sizable body of measured data (primarily collected for residential sector) documenting energy-saving effects of cool roofs as shown. Both measured data and simulations clearly demonstrate that increasing the albedo of roofs is an attractive (and cost-effective) way of reducing the net radiative heat gains through the roof and hence, reducing building cooling loads. To change the albedo, the rooftops of buildings may be painted with reflective coatings or covered with a new light-colored material. Since most roofs have regular maintenance schedules or need to be re-roofed or re-coated periodically, the change of the albedo should be done then. In that case, the cost would be limited to the incremental cost associated with the high-albedo material. In buildings and climates with significant air-conditioning use, increasing the albedo of roofs will reduce energy use and produce a stream of savings immediately.

  1. Efficiently-cooled plasmonic amorphous silicon solar cells integrated with a nano-coated heat-pipe plate.

    PubMed

    Zhang, Yinan; Du, Yanping; Shum, Clifford; Cai, Boyuan; Le, Nam Cao Hoai; Chen, Xi; Duck, Benjamin; Fell, Christopher; Zhu, Yonggang; Gu, Min

    2016-01-01

    Solar photovoltaics (PV) are emerging as a major alternative energy source. The cost of PV electricity depends on the efficiency of conversion of light to electricity. Despite of steady growth in the efficiency for several decades, little has been achieved to reduce the impact of real-world operating temperatures on this efficiency. Here we demonstrate a highly efficient cooling solution to the recently emerging high performance plasmonic solar cell technology by integrating an advanced nano-coated heat-pipe plate. This thermal cooling technology, efficient for both summer and winter time, demonstrates the heat transportation capability up to ten times higher than those of the metal plate and the conventional wickless heat-pipe plates. The reduction in temperature rise of the plasmonic solar cells operating under one sun condition can be as high as 46%, leading to an approximate 56% recovery in efficiency, which dramatically increases the energy yield of the plasmonic solar cells. This newly-developed, thermally-managed plasmonic solar cell device significantly extends the application scope of PV for highly efficient solar energy conversion. PMID:27113558

  2. Characterization of the Turbulent Magnetic Integral Length in the Solar Wind: From 0.3 to 5 Astronomical Units

    NASA Astrophysics Data System (ADS)

    Ruiz, M. E.; Dasso, S.; Matthaeus, W. H.; Weygand, J. M.

    2014-10-01

    The solar wind is a structured and complex system, in which the fields vary strongly over a wide range of spatial and temporal scales. As an example, the turbulent activity in the wind affects the evolution in the heliosphere of the integral turbulent scale or correlation length [ λ], usually associated with the breakpoint in the turbulent-energy spectrum that separates the inertial range from the injection range. This large variability of the fields demands a statistical description of the solar wind. We study the probability distribution function (PDF) of the magnetic-autocorrelation lengths observed in the solar wind at different distances from the Sun. We used observations from the Helios, ACE, and Ulysses spacecraft. We distinguished between the usual solar wind and one of its transient components (interplanetary coronal mass ejections, ICMEs), and also studied solar-wind samples with low and high proton beta [βp]. We find that in the last three regimes the PDF of λ is a log-normal function, consistent with the multiplicative and nonlinear processes that take place in the solar wind, the initial λ (before the Alfvénic point) being larger in ICMEs.

  3. Efficiently-cooled plasmonic amorphous silicon solar cells integrated with a nano-coated heat-pipe plate

    PubMed Central

    Zhang, Yinan; Du, Yanping; Shum, Clifford; Cai, Boyuan; Le, Nam Cao Hoai; Chen, Xi; Duck, Benjamin; Fell, Christopher; Zhu, Yonggang; Gu, Min

    2016-01-01

    Solar photovoltaics (PV) are emerging as a major alternative energy source. The cost of PV electricity depends on the efficiency of conversion of light to electricity. Despite of steady growth in the efficiency for several decades, little has been achieved to reduce the impact of real-world operating temperatures on this efficiency. Here we demonstrate a highly efficient cooling solution to the recently emerging high performance plasmonic solar cell technology by integrating an advanced nano-coated heat-pipe plate. This thermal cooling technology, efficient for both summer and winter time, demonstrates the heat transportation capability up to ten times higher than those of the metal plate and the conventional wickless heat-pipe plates. The reduction in temperature rise of the plasmonic solar cells operating under one sun condition can be as high as 46%, leading to an approximate 56% recovery in efficiency, which dramatically increases the energy yield of the plasmonic solar cells. This newly-developed, thermally-managed plasmonic solar cell device significantly extends the application scope of PV for highly efficient solar energy conversion. PMID:27113558

  4. Eastern Renewable Generation Integration Study: Flexibility and High Penetrations of Wind and Solar; NREL (National Renewable Energy Laboratory)

    SciTech Connect

    Bloom, Aaron; Townsend, Aaron; Palchak, David

    2015-07-29

    Balancing wind and solar in a model is relatively easy. All you need to do is assume a very large system with infinite flexibility! But what if you don't have an infinitely flexible system? What if there are thousands of generators nestled in a handful of regions that are unlikely to change their operational practices? Would you still have enough flexibility to balance hundreds of gigawatts of wind and solar at a 5 minute level? At NREL, we think we can, and our industry partners agree. This presentation was presented at the IEEE Power and Energy Society General Meeting by Aaron Bloom, highlighting results of the Eastern Renewable Generation Integration Study.

  5. Design issues for a cost-effective solar industrial process heat system

    NASA Astrophysics Data System (ADS)

    Deffenbaugh, D. M.

    1980-08-01

    Several issues which are essential for making solar industrial process heat systems cost-effective are identified. These issues are examined under the following headings; (1) industrial process interface, (2) solar collector selection, (3) roof versus ground mounting of collectors, (4) roof-mounted structure analysis, (5) tax incentives, and (6) mass production effects.

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

    SciTech Connect

    Syd S. Peng

    2005-01-15

    In this quarter, the field, theoretical and programming works have been performed toward achieving the research goals set in the proposal. The main accomplishments in this quarter included: (1) one more field test has been conducted in an underground coal mine, (2) optimization studies of the control parameters have been conducted, (3) method to use torque to thrust ratio as indicator of rock relative hardness has also been explored, and (4) about 98% of the development work for the roof geology mapping program, MRGIS, has completed, (5) A real time roof geology mapping system for roof bolters in limestone mine, including a special version of the geology mapping program and hardware, has already been verified to perform very well in underground production condition.

  7. On the intraday resampling of time-integrated values of solar radiation

    NASA Astrophysics Data System (ADS)

    Blanc, Ph.; Wald, L.

    2010-09-01

    Measurements of solar downwelling radiation are made at ground level by integrating the received energy during an integration time, e.g., 1 h. The sampling time, is usually equal to the integration time. In this way, one constructs time series of integrated values. Further processing of such measurements often requires the oversampling of the data in order to obtain radiation values at a higher temporal sampling. For example, the assessment of the direct irradiation in normal incidence from hourly values of beam irradiation on a horizontal surface requires a resampling of the time series to a higher temporal resolution, e.g., one minute, to account precisely of the solar position dynamics during an hour. Many interpolation techniques are found in literature for this oversampling processing. They are mainly based on standard signal processing techniques such as nearest neighbours, linear, cubic or spline interpolation. This communication deals with beam irradiation on horizontal surface and focuses on the resampling of 1-h values or 15-min to 1-min values. Several techniques are used and their merits are discussed. Resampling can be performed on irradiation values; we show that better results are attained by resampling transformed values, such the clearness or clear-sky indices, then reversing the resampled indices into irradiation. Furthermore, we express the consistency property: the average of the oversampled temporal series should be equal to that of the original time series. We show that this consistency property is not respected by the usual resampling techniques. The error is small as an average but it is concentrated mainly in the high frequencies and therefore has an impact on the computation of the direct irradiation in normal incidence. This impact may be noticeable at different time-scales: intraday, day, month, and year. Our theoretical expectations are confirmed by an experimentation made with high-quality time series of 1-min irradiation measured by the BSRN station in Payerne, Switzerland. This original time series serves as a reference. We average these values every 15 min and 1 h, in order to obtain time series of 15-min and 1-h irradiation. Linear and spline cubic interpolations are applied on either irradiation or clearness index. Results are compared to the reference. The respect of the consistency property is assessed. The time series of differences are summarized in terms of root mean square error, correlation and Kolmogorov-Smirnov test applied to the discrepancies in cumulative distribution functions. Fourier analyses are made to assess the power spectral density and, therefore, the temporal correlation of the estimation errors with respect to the different interpolation approaches. Unsurprisingly, we found that 1) resampling clearness index is more accurate than resampling irradiation, and 2) results are better in clear and overcast skies than in intermediate skies. The relative error in the consistency property on the hourly sum of beam horizontal irradiation in term of root mean square error ranges between 3 % and 6 % with a subsequent error on the estimation of the direct normal incidence between 9 % and 15 %.

  8. Green Roofs: Federal Energy Management Program (FEMP) Federal Technology Alert

    SciTech Connect

    Scholz-Barth, K.; Tanner, S.

    2004-09-01

    In a ''green roof,'' a layer of vegetation (e.g., a roof garden) covers the surface of a roof to provide shade, cooler indoor and outdoor temperatures, and effective storm-water management to reduce runoff. The main components are waterproofing, soil, and plants. There are two basic kinds: intensive and extensive. An intensive green roof often features large shrubs and trees, and it can be expensive to install and maintain. An extensive green roof features shallow soil and low-growing, horizontally spreading plants that can thrive in the alpine conditions of many rooftops. These plants do not require a lot of water or soil, and they can tolerate a significant amount of exposure to the sun and wind. This Federal Technology Alert focuses on the benefits, design, and implementation of extensive green roofs and includes criteria for their use on federal facilities.

  9. Relationship of roof rat population indices with damage to sugarcane

    USGS Publications Warehouse

    Lefebvre, Lynn W.; Engeman, Richard M.; Decker, David G.; Holler, Nicholas R.

    1989-01-01

    Roof rats (Rattus rattus) cause substantial damage to sugarcane in South Florida (Samol 1972; Lefebvre et al. 1978, 1985). Accurate estimates of roof rat populations in sugarcane fields would be useful for determining when to to treat a field to control roof rats and for assessing the efficacy of control. However, previous studies have indicated that roof rats exhibit trap shyness, which makes capture-recapture population estimates difficult (Lefebvre et al. 1978, 1985; Holler et al., 1981). Until trapping methods are sufficiently improved to allow accurate population estimates, indices of population size that relate to damage need to be developed. The objectives of our study were to examine the relationship of several indices of roof rat populations to the percentage of sugarcane stalks damaged at harvest; to determine which population index would be most useful for sugarcane growers; and to report on a test of several types of live traps for roof rats.

  10. Proceedings of the sustainable low-slope roofing workshop

    SciTech Connect

    Desjarlais, A.

    1997-02-01

    On October 9--10, 1996, a group of approximately 150 roofing professionals attended the Sustainable Low-Slope Roofing Workshop at Pollard Auditorium in Oak Ridge, Tennessee. A list of attendees is appended to the proceedings. For the purpose of the workshop, sustainable low-slope roofing was defined as a low-slope roofing system that is designed, constructed, maintained, rehabilitated, or demolished with an emphasis throughout its life-cycle on the efficient use of natural resources and the maintenance of the global environment. At the workshop, 20 papers regarding various aspects of sustainable roofing were presented. Issues such as durability, maintenance, energy considerations, the economics of sustainable construction, coatings, and case studies of sustainable roofing systems are discussed in the papers.

  11. Solar Powered Classroom

    ScienceCinema

    none

    2013-06-27

    A group of fourth graders in Durham, North Carolina, are showing America the way to a clean energy future. They are installing solar panels on their classroom roof for a project that goes above and beyond a normal day in school. From researching solar panel installation, to generating funds for the project via Kickstarter, these are students who put their plans into action. Their accomplishments go beyond the classroom and stress the importance of getting people of all ages involved in renewable energy.

  12. Solar Powered Classroom

    SciTech Connect

    2013-06-13

    A group of fourth graders in Durham, North Carolina, are showing America the way to a clean energy future. They are installing solar panels on their classroom roof for a project that goes above and beyond a normal day in school. From researching solar panel installation, to generating funds for the project via Kickstarter, these are students who put their plans into action. Their accomplishments go beyond the classroom and stress the importance of getting people of all ages involved in renewable energy.

  13. Double Power Laws in the Event-integrated Solar Energetic Particle Spectrum

    NASA Astrophysics Data System (ADS)

    Zhao, Lulu; Zhang, Ming; Rassoul, Hamid K.

    2016-04-01

    A double power law or a power law with exponential rollover at a few to tens of MeV nucleon-1 of the event-integrated differential spectra has been reported in many solar energetic particle (SEP) events. The rollover energies per nucleon of different elements correlate with a particle's charge-to-mass ratio (Q/A). The probable causes are suggested as residing in shock finite lifetimes, shock finite sizes, shock geometry, and an adiabatic cooling effect. In this work, we conduct a numerical simulation to investigate a particle's transport process in the inner heliosphere. We solve the focused transport equation using a time-backward Markov stochastic approach. The convection, magnetic focusing, adiabatic cooling effect, and pitch-angle scattering are included. The effects that the interplanetary turbulence imposes on the shape of the resulting SEP spectra are examined. By assuming a pure power-law differential spectrum at the Sun, a perfect double-power-law feature with a break energy ranging from 10 to 120 MeV nucleon-1 is obtained at 1 au. We found that the double power law of the differential energy spectrum is a robust result of SEP interplanetary propagation. It works for many assumptions of interplanetary turbulence spectra that give various forms of momentum dependence of a particle's mean free path. The different spectral shapes in low-energy and high-energy ends are not just a transition from the convection-dominated propagation to diffusion-dominated propagation.

  14. CO2 post-combustion capture in coal-fired power plants integrated with solar systems

    NASA Astrophysics Data System (ADS)

    Carapellucci, R.; Giordano, L.; Vaccarelli, M.

    2015-11-01

    The majority of the World's primary energy consumption is still based on fossil fuels, representing the largest source of global CO2 emissions. According to the Intergovernmental Panel on Climate Change (IPCC), such emissions must be significantly reduced in order to avoid the dramatic consequences of global warming. A potential way to achieve this ambitious goal is represented by the implementation of CCS (Carbon Capture and Storage) technologies. However, the significant amount of energy required by the CCS systems still represents one the major barriers for their deployment. Focusing on post-combustion capture based on amine absorption, several interesting options have been investigated to compensate the energy losses due to solvent regeneration, also using renewable energy sources. One of the most promising is based on the use of concentrating solar power (CSP), providing a part of the energy requirement of the capture island. In this study the integration of a CSP system into a coal-fired power plant with CO2 postcombustion capture is investigated. Basically, a CSP system is used to support the heat requirement for amine regeneration, by producing saturated steam at low temperature. This allows to reduce or even eliminate the conventional steam extraction from the main power plant, affecting positively net power production and efficiency. The energy analysis of the whole system is carried out using the GateCycle software to simulate the coal-fired power plant and ChemCad platform for the CO2 capture process based on amine absorption.

  15. Development, fabrication, and testing of a new design for the integral compound parabolic evacuated solar collector

    SciTech Connect

    Duff, W.S.; Duquette, R.; Winston, R.; O`Gallagher, J.J.

    1997-12-31

    A new integral compound parabolic evacuated solar collector (ICPC) design was devised at the University of Chicago in 1995 by application of non imaging optics principles to a different target geometry. This new ICPC promises low manufacturing cost combined with excellent performance and reliability. Beginning in mid February 1996, 1.6 meter (5.25 ft.) versions of this ICPC, called mini tubes, have been designed, fabricated, and tested by Colorado State University. The development effort focused on, manufactureability, performance, and reliability. The development process consisted of about twenty iterations of a three step process: (1) design revision, (2) fabrication, and (3) testing and evaluation of short versions of the mini-tubes. Testing was conducted in a variety of ways and performance achievements were judged numerically. All goals were exceeded, matched, or came within a few percent. This paper presents the mini-tube development /work for this new ICPC, provide details on the testing and evaluation, and presents the performance of the final mini tube.

  16. Actinometric measurement of solar ultraviolet and development of a weighted solar UV integral. [photochemical reaction rate determination

    NASA Technical Reports Server (NTRS)

    Gupta, A.; Coulbert, C.

    1978-01-01

    An actinometer has been developed to measure outdoor irradiance in the range 295-400 nm. Actinometric measurements of radiation are based on determination of photochemical reaction rates for reactions of known quantum efficiency. Actinometers have the advantage of providing irradiance data over surfaces of difficult accessibility; in addition, actinometrically determined irradiance data are wavelength weighted and therefore provide a useful means of assessing the degradation rates of polymers employed in solar energy systems.

  17. Impact of cutter roof failure on small mine operators

    SciTech Connect

    Bauer, E.R. )

    1993-01-01

    The US Bureau of Mines has conducted research to gain a basis for recommending methods to predict and prevent the occurrence of cutter roof failure, a common ground control problem in the Appalachian Coalfields. Cutter roof failure can be difficult to predict and control, and be especially devastating to small miner operators with limited resources and small profit margins. Bureau research has found four distinct factors to be initiators of cutter roof failure: (1) high horizontal roof stress, (2) surface topographic variations, (3) roof rock characteristics and (4) geologic anomalies. Effective control of cutter roof is possible through improved bolting techniques, entry and mine reorientation, and entry and pillar size modifications, all of which may not be economically feasible for small mine operators. The result is that small mine operators are forced to continue mining where less than ideal roof conditions are present. Ultimately, cutter roof failure could result in the closure of some small mine operations. Extensive Bureau cutter roof research can increase small mine operator's awareness of this ground failure, provide insight for predicting its cause, and suggest appropriate methods of controlling its occurrence.

  18. 43. TOP OF SOUTHEAST TOWER FROM SOUTH TOWER ROOF, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    43. TOP OF SOUTHEAST TOWER FROM SOUTH TOWER ROOF, LOOKING EAST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  19. 44. ARTS AND INDUSTRIES BUILDING FROM SOUTH TOWER ROOF, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    44. ARTS AND INDUSTRIES BUILDING FROM SOUTH TOWER ROOF, LOOKING SOUTHEAST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  20. 39. CLOSER VIEW OF CAMPANILE FROM SOUTH TOWER ROOF, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    39. CLOSER VIEW OF CAMPANILE FROM SOUTH TOWER ROOF, LOOKING NORTHEAST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  1. 40. CAMPANILE & SOUTHEAST TOWER FROM SOUTH TOWER ROOF, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    40. CAMPANILE & SOUTHEAST TOWER FROM SOUTH TOWER ROOF, LOOKING EAST BY NORTHEAST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  2. 37. NORTH TOWER UPPER ZONE FROM SOUTH TOWER ROOF, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    37. NORTH TOWER UPPER ZONE FROM SOUTH TOWER ROOF, LOOKING NORTH - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  3. 47. NORTHWEST TOWER FROM SOUTH TOWER ROOF, LOOKING NORTH BY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    47. NORTHWEST TOWER FROM SOUTH TOWER ROOF, LOOKING NORTH BY NORTHWEST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  4. 10. INTERIOR VIEW OF BUILDING 251, SHOWING DETAIL OF ROOF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. INTERIOR VIEW OF BUILDING 251, SHOWING DETAIL OF ROOF TRUSSES, LOOKING SOUTHEAST - Frankford Arsenal, Building No. 251, Northeast corner Hagner Road & Walbach Street, Philadelphia, Philadelphia County, PA

  5. 36. FLAG TOWER CLOCK ZONE FROM SOUTH TOWER ROOF, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    36. FLAG TOWER CLOCK ZONE FROM SOUTH TOWER ROOF, LOOKING NORTH - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  6. roof truss detail, historic strap hinge detail Chopawamsic Recreational ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    roof truss detail, historic strap hinge detail - Chopawamsic Recreational Demonstration Area - Cabin Camp 1, Main Arts and Crafts Lodge, Prince William Forest Park, Triangle, Prince William County, VA

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

    SciTech Connect

    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. 5. VIEW OF VENTILATION HOUSES AND ROOF MONITOR FROM SOUTHEAST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. VIEW OF VENTILATION HOUSES AND ROOF MONITOR FROM SOUTHEAST CORNER OF ROOF. ROOF MONITOR WINDOWS HAVE BEEN INFILLED WITH BRICK. THE VENTILATION HOUSES ARE PART OF THE ORIGINAL CENTRAL AIR CONDITIONING SYSTEM AND CONTAINED AIR WASHERS, FANS AND OTHER HUMIDFYING EQUIPMENT FROM PARKS-CRAMER COMPANY OF FITCHBURG, MASSACHUSETTS. LOCATING THIS EQUIPMENT ON THE ROOF MADE IT UNNECESSARY TO CONSTRUCT A FULL BASEMENT, AND THEREFORE LOWERED CONSTRUCTION COSTS. THIS ARRANGEMENT ALSO PUT THE AIR CONDITIONING EQUIPMENT CLOSEST TO THE TOP FLOOR SPINNING ROOM, WHICH HAD THE GREATEST COOLING REQUIREMENTS. - Stark Mill, 117 Corinth Road, Hogansville, Troup County, GA

  9. ASTM standards for measuring solar reflectance and infrared emittance of construction materials and comparing their steady-state surface temperatures

    SciTech Connect

    Akbari, H.; Levinson, R.; Berdahl, P.

    1996-08-01

    Numerous experiments on individual buildings in California and Florida show that painting roofs white reduces air conditioning load up to 50%, depending on the thermal resistance or amount of insulation under the roof. The savings, of course, are strong functions of the thermal integrity of a building and climate. In earlier work, the authors have estimated the national energy savings potential from reflective roofs and paved surfaces. Achieving this potential, however, is conditional on receiving the necessary Federal, states, and electric utilities support to develop materials with high solar reflectance and design effective implementation programs. An important step in initiating an effective program in this area is to work with the american Society for Testing and Materials (ASTM) and the industry to create test procedures, rating, and labeling for building and paving materials. A subcommittee of ASTM E06, E06.42, on Cool Construction Materials, was formed as the vehicle to develop standard practices for measuring, rating, and labeling cool construction materials. The subcommittee has also undertaken the development of a standard practice for calculating a solar reflectance index (SRI) of horizontal and low-sloped surfaces. SRI is a measure of the relative steady-state temperature of a surface with respect to a standard white surface (SRI = 100) and a standard black surface (SRI = 0) under standard solar and ambient conditions. This paper discusses the technical issues relating to development of these two ASTM standards.

  10. SOLERAS - Solar Controlled Environment Agriculture Project. Final report, Volume 5. Science Applications, Incorporated system requirements definition

    SciTech Connect

    Not Available

    1985-01-01

    This report sets forth the system requirements for a Solar Controlled-Environment Agriculture System (SCEAS) Project. In the report a conceptual baseline system description for an engineering test facility is given. This baseline system employs a fluid roof/roof filter in combination with a large storage tank and a ground water heat exchanger in order to provide cooling and heating as needed. Desalination is accomplished by pretreatment followed by reverse osmosis. Energy is provided by means of photovoltaics and wind machines in conjunction with storage batteries. Site and climatic data needed in the design process are given. System performance specifications and integrated system design criteria are set forth. Detailed subsystem design criteria are presented and appropriate references documented.

  11. Study of thermal effects and optical properties of an innovative absorber in integrated collector storage solar water heater

    NASA Astrophysics Data System (ADS)

    Taheri, Yaser; Alimardani, Kazem; Ziapour, Behrooz M.

    2015-10-01

    Solar passive water heaters are potential candidates for enhanced heat transfer. Solar water heaters with an integrated water tank and with the low temperature energy resource are used as the simplest and cheapest recipient devices of the solar energy for heating and supplying hot water in the buildings. The solar thermal performances of one primitive absorber were determined by using both the experimental and the simulation model of it. All materials applied for absorber such as the cover glass, the black colored sands and the V shaped galvanized plate were submerged into the water. The water storage tank was manufactured from galvanized sheet of 0.0015 m in thickness and the effective area of the collector was 0.67 m2. The absorber was installed on a compact solar water heater. The constructed flat-plate collectors were tested outdoors. However the simulation results showed that the absorbers operated near to the gray materials and all experimental results showed that the thermal efficiencies of the collector are over than 70 %.

  12. 10-MWe solar-thermal central-receiver pilot plant, solar-facilities design integration: system integration laboratory test plan (RADL item 6-4)

    SciTech Connect

    Not Available

    1980-10-01

    A general demonstration test plan is provided for the activities to be accomplished at the Systems Integration Laboratory. The Master Control System, Subsystem Distributed Process Control, Representative Signal Conditioning Units, and Redline Units from the Receiver Subsystem and the Thermal Storage Subsystem and other external interface operational functions will be integrated and functionally demonstrated. The Beckman Multivariable Control Unit will be tested for frequency response, static checks, configuration changes, switching transients, and input-output interfaces. Maximum System Integration Laboratory testing will demonstrate the operational readiness of Pilot Plant controls and external interfaces that are available. Minimum System Integration Laboratory testing will be accomplished with reduced set of hardware, which will provide capability for continued development and demonstration of Operational Control System plant control application software. Beam Control System Integration Laboratory testing will demonstrate the operational readiness of the Beam Control System equipment and software. (LEW)

  13. High-Performance Integrated Perovskite and Organic Solar Cells with Enhanced Fill Factors and Near-Infrared Harvesting.

    PubMed

    Kim, Junghwan; Kim, Geunjin; Back, Hyungcheol; Kong, Jaemin; Hwang, In-Wook; Kim, Tae Kyun; Kwon, Sooncheol; Lee, Jong-Hoon; Lee, Jinho; Yu, Kilho; Lee, Chang-Lyoul; Kang, Hongkyu; Lee, Kwanghee

    2016-04-01

    Highly efficient P-I-N type perovskite/bulk-heterojunction (BHJ) integrated solar cells (ISCs) with enhanced fill factor (FF) (≈80%) and high near-infrared harvesting (>30%) are demonstrated by optimizing the BHJ morphology with a novel n-type polymer, N2200, and a new solvent-processing additive. This work proves the feasibility of highly efficient ISCs with panchromatic absorption as a new photovoltaic architecture and provides important design rules for optimizing ISCs. PMID:26917008

  14. 40 CFR 65.43 - Fixed roof with an internal floating roof (IFR).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... floating roof, the seal, gaskets, slotted membranes, and sleeve seals (if any) each time the storage vessel... primary seal, the secondary seal, gaskets, slotted membranes, and sleeve seals (if any) each time the..., gaskets, slotted membranes, and sleeve seals (if any) each time the vessel is emptied, but no...

  15. 40 CFR 65.43 - Fixed roof with an internal floating roof (IFR).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... floating roof, the seal, gaskets, slotted membranes, and sleeve seals (if any) each time the storage vessel... primary seal, the secondary seal, gaskets, slotted membranes, and sleeve seals (if any) each time the..., gaskets, slotted membranes, and sleeve seals (if any) each time the vessel is emptied, but no...

  16. THE EVERGREEN ROOF PROJECT: STANDARDS, METHODS AND SOFTWARE FOR EVALUATING LIVING ROOF SYSTEMS

    EPA Science Inventory

    The Evergreen Roof Project set out four objectives for Phase I of our project and has made sufficient progress on all of those objectives to qualify this phase as a success. Through an extensive literature review and discussions with researchers, designers, inst...

  17. Integral glass encapsulation for solar arrays. Quarterly progress Report No. 12, October 11, 1979-January 10, 1980

    SciTech Connect

    Young, Peter R.

    1980-02-01

    This is the twelfth quarterly report under a JPL/DOE program for the development of electrostatic bonding as a method of integral encapsulation of solar cells in glass. Efforts for the current phase of this program are to continue to demonstrate process uniformity of electrostatic bonding encapsulation. Additional goals of this program are to develop preformed (wire mesh) contacts as a method of integrating cell processing into the encapsulation procedure resulting in a low cost module assembly technique, and to investigate low-temperature bonding to commercially available glass (pyrex) substrates. Progress is reported.

  18. SEPS mission and system integration/interface requirements for the space transportation system. [Solar Electric Propulsion System

    NASA Technical Reports Server (NTRS)

    Cork, M. J.; Barnett, P. M.; Shaffer, J., Jr.; Doran, B. J.

    1979-01-01

    Earth escape mission requirements on Solar Electric Propulsion System (SEPS), and the interface definition and planned integration between SEPS, user spacecraft, and other elements of the STS. Emphasis is placed on the Comet rendezvous mission, scheduled to be the first SEPS user. Interactive SEPS interface characteristics with spacecraft and mission, as well as the multiple organizations and inter-related development schedules required to integrate the SEPS with spacecraft and STS, require early attention to definition of interfaces in order to assure a successful path to the first SEPS launch in July 1985

  19. NV Energy Solar Integration Study: Cycling and Movements of Conventional Generators for Balancing Services

    SciTech Connect

    Diao, Ruisheng; Lu, Shuai; Etingov, Pavel V.; Ma, Jian; Makarov, Yuri V.; Guo, Xinxin

    2011-07-01

    With an increasing penetration level of solar power in the southern Nevada system, the impact of solar on system operations needs to be carefully studied from various perspectives. Qualitatively, it is expected that the balancing requirements to compensate for solar power variability will be larger in magnitude; meanwhile, generators providing load following and regulation services will be moved up or down more frequently. One of the most important tasks is to quantitatively evaluate the cycling and movements of conventional generators with solar power at different penetration levels. This study is focused on developing effective methodologies for this goal and providing a basis for evaluating the wear and tear of the conventional generators

  20. Building integrated PV for commercial and institutional structures, a sourcebook for architects

    SciTech Connect

    Eiffert, P.; Kiss, G.

    2000-02-14

    This sourcebook on building-integrated photovoltaics (BIPV) is intended for architects and designers interested in learning more about today's sustainable solar buildings. The booklet includes 16 design briefs describing actual structures; they illustrate how electricity-generating BIPV products (such as special roofing systems, vertical-wall systems, skylights, and awnings, all of which contain PV cells, modules, and films) can be integrated successfully into many different kinds of buildings. It also contains basic information about BIPV technologies, an overview of US product development activities and development programs, descriptions of major software design tools, and a bibliography.