National Library of Energy BETA

Sample records for diffuse solar radiation

  1. Estimation of diffuse from measured global solar radiation

    SciTech Connect (OSTI)

    Moriarty, W.W. )

    1991-01-01

    A data set of quality controlled radiation observations from stations scattered throughout Australia was formed and further screened to remove residual doubtful observations. It was then divided into groups by solar elevation, and used to find average relationships for each elevation group between relative global radiation (clearness index - the measured global radiation expressed as a proportion of the radiation on a horizontal surface at the top of the atmosphere) and relative diffuse radiation. Clear-cut relationships were found, which were then fitted by polynomial expressions giving the relative diffuse radiation as a function of relative global radiation and solar elevation. When these expressions were used to estimate the diffuse radiation from the global, the results had a slightly smaller spread of errors than those from an earlier technique given by Spencer. It was found that the errors were related to cloud amount, and further relationships were developed giving the errors as functions of global radiation, solar elevation, and the fraction of sky obscured by high cloud and by opaque (low and middle level) cloud. When these relationships were used to adjust the first estimates of diffuse radiation, there was a considerable reduction in the number of large errors.

  2. NREL: Solar Radiation Research - Solar Radiation Research Laboratory...

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

    Solar Radiation Research Laboratory Photographs The Solar Radiation Research Laboratory (SRRL) houses more than 70 instruments to analyze and record solar radiation and surface ...

  3. ARM: Baseline Solar Radiation Network (BSRN): solar irradiances...

    Office of Scientific and Technical Information (OSTI)

    Baseline Solar Radiation Network (BSRN): solar irradiances Title: ARM: Baseline Solar Radiation Network (BSRN): solar irradiances Baseline Solar Radiation Network (BSRN): solar ...

  4. Solar Radiation Empirical Quality Assessment

    Energy Science and Technology Software Center (OSTI)

    1994-03-01

    The SERIQC1 subroutine performs quality assessment of one, two, or three-component solar radiation data (global horizontal, direct normal, and diffuse horizontal) obtained from one-minute to one-hour integrations. Included in the package is the QCFIT tool to derive expected values from historical data, and the SERIQC1 subroutine to assess the quality of measurement data.

  5. Solar and Infrared Radiation Station (SIRS) Handbook

    SciTech Connect (OSTI)

    Stoffel, T

    2005-07-01

    The Solar Infrared Radiation Station (SIRS) provides continuous measurements of broadband shortwave (solar) and longwave (atmospheric or infrared) irradiances for downwelling and upwelling components. The following six irradiance measurements are collected from a network of stations to help determine the total radiative flux exchange within the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) Climate Research Facility: Direct normal shortwave (solar beam) Diffuse horizontal shortwave (sky) Global horizontal shortwave (total hemispheric) Upwelling shortwave (reflected) Downwelling longwave (atmospheric infrared) Upwelling longwave (surface infrared)

  6. Kenya Hourly DNI, GHI and Diffuse Solar Data - Datasets - OpenEI...

    Open Energy Info (EERE)

    Kenya Hourly DNI, GHI and Diffuse Solar Data Abstract Each data file is a set of hourly values of solar radiation (DNI, GHI and diffuse) and meteorological elements for a 1-year...

  7. Solar Position Algorithm for Solar Radiation Applications (Revised...

    Office of Scientific and Technical Information (OSTI)

    Solar Position Algorithm for Solar Radiation Applications (Revised) Citation Details In-Document Search Title: Solar Position Algorithm for Solar Radiation Applications (Revised) ...

  8. Solar Radiation Research Laboratory | Energy Systems Integration...

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

    Solar Radiation Research Laboratory Since 1981, NREL's Solar Radiation Research Laboratory (SRRL) has been collecting continuous measurements of basic solar radiation components, ...

  9. Solar Energy Evolution and Diffusion Studies

    Broader source: Energy.gov [DOE]

    Through the Solar Energy Evolution and Diffusion Studies, or SEEDS, program, seven projects are investigating strategies to accelerate the pace of change for solar energy technologies as they are...

  10. 20 Years of Solar Measurements: The Solar Radiation Research...

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

    Years of Solar Measurements: The Solar Radiation Research Laboratory (SRRL) at NREL Tom ... * Continuous measurements of key solar radiation resources * Calibrations of instruments ...

  11. On Correction of Diffuse Radiation Measured by MFRSR

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

    On Correction of Diffuse Radiation Measured by MFRSR T. B. Zhuravleva Institute of Atmospheric Optics, SB RAS Tomsk, Russia M. A. Sviridenkov and P. P. Anikin A. M. Obukhov Institute of Atmospheric Physics, RAS Moscow, Russia Introduction The multi-filter rotated shadowband radiometer (MFRSR) provides spectral direct, diffuse, and total horizontal solar irradiance measurements. Because the MFRSR's receiver has a non-Lambertian response, for a correct interpretation of measured radiation an

  12. Solar radiation absorbing material

    DOE Patents [OSTI]

    Googin, John M.; Schmitt, Charles R.; Schreyer, James M.; Whitehead, Harlan D.

    1977-01-01

    Solar energy absorbing means in solar collectors are provided by a solar selective carbon surface. A solar selective carbon surface is a microporous carbon surface having pores within the range of 0.2 to 2 micrometers. Such a surface is provided in a microporous carbon article by controlling the pore size. A thermally conductive substrate is provided with a solar selective surface by adhering an array of carbon particles in a suitable binder to the substrate, a majority of said particles having diameters within the range of about 0.2-10 microns.

  13. Estimation of solar radiation from Australian meteorological observations

    SciTech Connect (OSTI)

    Moriarty, W.W. )

    1991-01-01

    A carefully prepared set of Australian radiation and meteorological data was used to develop a system for estimating hourly or instantaneous broad direct, diffuse and global radiation from meteorological observations. For clear sky conditions relationships developed elsewhere were adapted to Australian data. For cloudy conditions the clouds were divided into two groups, high clouds and opaque (middle and low) clouds, and corrections were made to compensate for the bias due to reporting practices for almost clear and almost overcast skies. Careful consideration was given to the decrease of visible sky toward the horizon caused by the vertical extent of opaque clouds. Equations relating cloud and other meteorological observations to the direct and diffuse radiation contained four unknown quantities, functions of cloud amount and of solar elevation, which were estimated from the data. These were proportions of incident solar radiation passed on as direct and as diffuse radiation by high clouds, and as diffuse radiation by opaque clouds. When the resulting relationships were used to estimate global, direct and diffuse radiation on a horizontal surface, the results were good, especially for global radiation. Some discrepancies between estimates and measurements of diffuse and direct radiation were probably due to erroneously high measurements of diffuse radiation.

  14. Modeling heat conduction and radiation transport with the diffusion...

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

    heat conduction and radiation transport with the diffusion equation in NIF ALE-AMR This ... IOPscience Modeling Heat Conduction and Radiation Transport with the Diffusion Equation in ...

  15. FUNDING OPPORTUNITY ANNOUNCEMENT: SOLAR ENERGY EVOLUTION AND DIFFUSION

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

    STUDIES II - STATE ENERGY STRATEGIES (SEEDSII-SES) | Department of Energy FUNDING OPPORTUNITY ANNOUNCEMENT: SOLAR ENERGY EVOLUTION AND DIFFUSION STUDIES II - STATE ENERGY STRATEGIES (SEEDSII-SES) FUNDING OPPORTUNITY ANNOUNCEMENT: SOLAR ENERGY EVOLUTION AND DIFFUSION STUDIES II - STATE ENERGY STRATEGIES (SEEDSII-SES) FUNDING OPPORTUNITY ANNOUNCEMENT: SOLAR ENERGY EVOLUTION AND DIFFUSION STUDIES II - STATE ENERGY STRATEGIES (SEEDSII-SES) FUNDING OPPORTUNITY ANNOUNCEMENT: SOLAR ENERGY EVOLUTION

  16. Big Data Projects on Solar Technology Evolution and Diffusion...

    Energy Savers [EERE]

    Soft Costs Big Data Projects on Solar Technology Evolution and Diffusion: Kickoff Meeting ... Graphic showing a web of people with energy bolts connecting them. Through the SEEDS ...

  17. Fast All-sky Radiation Models for Solar applications (FARMS)...

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

    Find More Like This Return to Search Fast All-sky Radiation Models for Solar applications ... Radiative transfer (RT) models simulating broadband solar radiation have been widely used ...

  18. Historically Black Colleges and Universities (HBCU) Solar Radiation Monitoring Network

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

    The Historically Black Colleges and Universities (HBCU) Solar Radiation Monitoring Network operated from November 1985 through December 1996. The six-station network provided 5-minute averaged measurements of global and diffuse horizontal solar irradiance. The data were processed at the National Renewable Energy Laboratory (NREL) to improve the assessment of the solar radiation resources in the southeastern United States. Three of the stations also measured the direct-normal solar irradiance with a pyrheliometer mounted in an automatic sun tracker. All data are archived in the Standard Broadband Format (SBF) with quality-assessment indicators. Monthly data summaries and plots are also available for each month. In January 1997 the HBCU sites became part of the CONFRRM solar monitoring network.

  19. Solar Radiation Basics | Department of Energy

    Energy Savers [EERE]

    Solar radiation can be captured and turned into useful forms of energy, such as heat and electricity, using a variety of technologies. However, the technical feasibility and ...

  20. Solar Radiation Data from the World Radiation Data Centre (WRDC) Online Archive

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

    The WRDC, located at the Main Geophysical Observatory in St. Petersburg, Russia, serves as a central depository for solar radiation data collected at over 1000 measurement sites throughout the world. The WRDC was established in accordance with Resolution 31 of WMO Executive Committee XVIII in 1964. The WRDC centrally collects, archives and published radiometric data from the world to ensure the availability of these data for research by the international scientific community. The WRDC archive contains the following measurements (not all observations are made at all sites): • Global solar radiationDiffuse solar radiation • Downward atmospheric radiation • Sunshine duration • Direct solar radiation (hourly and instantaneous) • Net total radiation • Net terrestrial surface radiation (upward) • Terrestrial surface radiation • Reflected solar radiation • Spectral radiation components (instantaneous fluxes) At present, this online archive contains a subset of the data stored at the WRDC. As new measurements are received and processed, they are added to the archive. The archive currently contains all available data from 1964-1993.[From ôBackground on the WRDCö at http://wrdc-mgo.nrel.gov/html/about.html

  1. Big Data Projects on Solar Technology Evolution and Diffusion: Kickoff

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

    Meeting | Department of Energy Soft Costs » Big Data Projects on Solar Technology Evolution and Diffusion: Kickoff Meeting Big Data Projects on Solar Technology Evolution and Diffusion: Kickoff Meeting Graphic showing a web of people with energy bolts connecting them. Through the SEEDS program, seven projects are investigating strategies to accelerate the pace of change for solar energy technologies using cutting-edge analytical and computational tools, real-world market data, and pilot

  2. Solar Radiation Research Laboratory (Poster)

    SciTech Connect (OSTI)

    Stoffel, T.; Andreas, A.; Reda, I.; Dooraghi, M.; Habte, A.; Kutchenreiter, M.; Wilcox, 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).

  3. An Instrument Design Concept for Measuring Solar Diffuse Irradiance

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

    An Instrument Design Concept for Measuring Solar Diffuse Irradiance Rutledge, Charles NASA Langley Research Center Schuster, Greg NASA Langley Research Center Category: Instruments Recent effort towards the development of a diffuse horizontal solar irradiance standard group [Michalsky et.al. 2005] using well calibrated pyranometers suggested that inter-instrument differences in cosine response characteristics may be problematic. They showed a calibration method using overcast skies (an

  4. Spectral and temperature correction of silicon photovoltaic solar radiation detectors

    SciTech Connect (OSTI)

    Michalsky, J.J.; Perez, R.; Harrison, L. ); LeBaron, B.A. )

    1991-01-01

    Silicon photovoltaic sensors are an inexpensive alternative to standard thermopile sensors for the measurement of solar radiation. However, their temperature and spectral response render them less accurate for global horizontal irradiance and unsuitable for direct beam and diffuse horizontal irradiance unless they can be reliably corrected. A correction procedure for the rotating shadowband radiometer, which measures all three components, based on a three-way parameterization of the solar position and sky conditions is proposed. After correction, root-mean-square errors for the global and diffuse horizontal irradiance and the direct normal irradiance are about 10, 12, and 13 W/m{sup 2} in comparison with coincident, 5-minute thermopile measurements. While the numerical results are specific to the rotating shadowband instrument, the correction algorithm should apply universally.

  5. A hybrid transport-diffusion model for radiative transfer in absorbing and scattering media

    SciTech Connect (OSTI)

    Roger, M.; Caliot, C.; Crouseilles, N.; Coelho, P.J.

    2014-10-15

    A new multi-scale hybrid transport-diffusion model for radiative transfer is proposed in order to improve the efficiency of the calculations close to the diffusive regime, in absorbing and strongly scattering media. In this model, the radiative intensity is decomposed into a macroscopic component calculated by the diffusion equation, and a mesoscopic component. The transport equation for the mesoscopic component allows to correct the estimation of the diffusion equation, and then to obtain the solution of the linear radiative transfer equation. In this work, results are presented for stationary and transient radiative transfer cases, in examples which concern solar concentrated and optical tomography applications. The Monte Carlo and the discrete-ordinate methods are used to solve the mesoscopic equation. It is shown that the multi-scale model allows to improve the efficiency of the calculations when the medium is close to the diffusive regime. The proposed model is a good alternative for radiative transfer at the intermediate regime where the macroscopic diffusion equation is not accurate enough and the radiative transfer equation requires too much computational effort.

  6. Modeling Copper Diffusion in Polycrystalline CdTe Solar Cells

    SciTech Connect (OSTI)

    Akis, Richard; Brinkman, Daniel; Sankin, Igor; Fang, Tian; Guo, Da; Vasileska, Dragica; Ringhofer, Christain

    2014-06-06

    It is well known that Cu plays an important role in CdTe solar cell performance as a dopant. In this work, a finite-difference method is developed and used to simulate Cu diffusion in CdTe solar cells. In the simulations, which are done on a two-dimensional (2D) domain, the CdTe is assumed to be polycrystalline, with the individual grains separated by grain boundaries. When used to fit experimental Cu concentration data, bulk and grain boundary diffusion coefficients and activation energies for CdTe can be extracted. In the past, diffusion coefficients have been typically obtained by fitting data to simple functional forms of limited validity. By doing full simulations, the simplifying assumptions used in those analytical models are avoided and diffusion parameters can thus be determined more accurately

  7. Spectral Solar Radiation Data Base at NREL

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

    The Solar Energy Research Institute (SERI)*, Electric Power Research Institute (EPRI), Florida Solar Energy Center (FSEC), and Pacific Gas and Electric Company (PG&E) cooperated to produce a spectral solar radiation data base representing a range of atmospheric conditions (or climates) that is applicable to several different types of solar collectors. Data that are included in the data base were collected at FSEC from October 1986 to April 1988, and at PG&E from April 1987 to April 1988. FSEC operated one EPRI and one SERI spectroradiometer almost daily at Cape Canaveral, which contributed nearly 2800 spectra to the data base. PG&E operated one EPRI spectroradiometer at San Ramon, Calif., as resources permitted, contributing nearly 300 spectra to the data base. SERI collected about 200 spectra in the Denver/Golden, Colo., area form November 1987 to February 1988 as part of a research project to study urban spectral solar radiation, and added these data to the data base. *In September 1991 the Solar Energy Research Institute became the National Renewable Energy Laboratory. [Description taken from http://rredc.nrel.gov/solar/old_data/spectral/

  8. Posters Mean Fluxes of Visible Solar Radiation in Broken Clouds

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

    7 Posters Mean Fluxes of Visible Solar Radiation in Broken Clouds V. E. Zuev, G. A. Titov, ... Introduction Generally, radiation codes for general circulation models (GCMs) include, ...

  9. Fast All-Sky Radiation Model for Solar Applications (FARMS):...

    Office of Scientific and Technical Information (OSTI)

    Fast All-Sky Radiation Model for Solar Applications (FARMS): A Brief Overview of ... Citation Details In-Document Search Title: Fast All-Sky Radiation Model for Solar ...

  10. Solar radiation characteristics in Abu Dhabi

    SciTech Connect (OSTI)

    El-Nashar, A.M. )

    1991-01-01

    Based on the instantaneous global and diffuse radiation measurements made in Abu Dhabi, UAE, during 1987, the instantaneous values of the clearness index, diffuse fraction, atmospheric transmittance, and extinction coefficient were estimated and found to be strongly dependnet on the air mass and month of the year. Therefore, correlations between each of these parameters versus the air mass and month of the year were developed using the least-squares technique. The diffuse fraction may alternatively be correlated against the clearness index and the air mass with no seasonal influence. The beam transmittance was estimated theoretically using the two-layer atmospheric model and making use of the correlation developed previously for the extinction coefficient. The model was found to yield satisfactory results. The diffuse transmittance was also estimated theoretically using both the RSC model and the isotropic scattering model with good agreement with the data obtained.

  11. Turning collectors for solar radiation

    DOE Patents [OSTI]

    Barak, Amitzur Z.

    1976-01-01

    A device is provided for turning a solar collector about the polar axis so that the collector is directed toward the sun as the sun tracks the sky each day. It includes two heat-expansive elements and a shadow plate. In the morning a first expansive element is heated, expands to turn the collector to face the sun, while the second expansive element is shaded by the plate. In the afternoon the second element is heated, expands to turn the collector to face the sun, while the first is shaded by the plate.

  12. Absorption of solar radiation in broken clouds

    SciTech Connect (OSTI)

    Zuev, V.E.; Titov, G.A.; Zhuravleva, T.B.

    1996-04-01

    It is recognized now that the plane-parallel model unsatisfactorily describes the transfer of radiation through broken clouds and that, consequently, the radiation codes of general circulation models (GCMs) must be refined. However, before any refinement in a GCM code is made, it is necessary to investigate the dependence of radiative characteristics on the effects caused by the random geometry of cloud fields. Such studies for mean fluxes of downwelling and upwelling solar radiation in the visible and near-infrared (IR) spectral range were performed by Zuev et al. In this work, we investigate the mean spectral and integrated absorption of solar radiation by broken clouds (in what follows, the term {open_quotes}mean{close_quotes} will be implied but not used, for convenience). To evaluate the potential effect of stochastic geometry, we will compare the absorption by cumulus (0.5 {le} {gamma} {le} 2) to that by equivalent stratus ({gamma} <<1) clouds; here {gamma} = H/D, H is the cloud layer thickness and D the characteristic horizontal cloud size. The equivalent stratus clouds differ from cumulus only in the aspect ratio {gamma}, all the other parameters coinciding.

  13. NREL Updates National Solar Radiation Database - News Releases | NREL

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

    Updates National Solar Radiation Database May 25, 2007 The Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) and collaborators have updated the National Solar Radiation Database, a planning tool that provides critical information about the amount of solar energy that is available at any given location. The database is widely used by solar system designers, building architects and engineers, renewable energy analysts and others to plan, size and site solar energy systems.

  14. Three-temperature plasma shock solutions with gray radiation diffusion

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

    Johnson, Bryan M.; Klein, Richard I.

    2016-04-19

    Here we discuss the effects of radiation on the structure of shocks in a fully ionized plasma are investigated by solving the steady-state fluid equations for ions, electrons, and radiation. The electrons and ions are assumed to have the same bulk velocity but separate temperatures, and the radiation is modeled with the gray diffusion approximation. Both electron and ion conduction are included, as well as ion viscosity. When the material is optically thin, three-temperature behavior occurs. When the diffusive flux of radiation is important but radiation pressure is not, two-temperature behavior occurs, with the electrons strongly coupled to the radiation.more » Since the radiation heats the electrons on length scales that are much longer than the electron–ion Coulomb coupling length scale, these solutions resemble radiative shock solutions rather than plasma shock solutions that neglect radiation. When radiation pressure is important, all three components are strongly coupled. Results with constant values for the transport and coupling coefficients are compared to a full numerical simulation with a good match between the two, demonstrating that steady shock solutions constitute a straightforward and comprehensive verification test methodology for multi-physics numerical algorithms.« less

  15. Solar Kit Lessons

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

    Solar Kit Lessons Middle School Curriculum Created by Northeast Sustainable Energy Association (NESEA) Click on the links below to take you to the Chapter heading: Solar Cell Inquiry Sunshine Timer Parts of a Solar Panel Part 1 Parts of a Solar Panel Part 2 Build a Simple Ammeter Solar-Powered Battery Charger Positioning Solar Panels 1 Positioning Solar Panels 2 Properties of Solar Radiation: Reflection, Transmission, and Absorption Properties of Solar Radiation: Direct and Diffuse Light Power

  16. Glass diffusion source for constraining BSF region of a solar cell

    DOE Patents [OSTI]

    Lesk, I.A.; Pryor, R.A.; Coleman, M.G.

    1982-08-27

    The present invention is directed to a method of fabricating a solar cell comprising simultaneous diffusion of the p and n dopant materials into the solar cell substrate. The simultaneous diffusion process is preceded by deposition of a capping layer impervious to doping by thermal diffusion processes.

  17. High efficiency, radiation-hard solar cells

    SciTech Connect (OSTI)

    Ager III, J.W.; Walukiewicz, W.

    2004-10-22

    The direct gap of the In{sub 1-x}Ga{sub x}N alloy system extends continuously from InN (0.7 eV, in the near IR) to GaN (3.4 eV, in the mid-ultraviolet). This opens the intriguing possibility of using this single ternary alloy system in single or multi-junction (MJ) solar cells of the type used for space-based surveillance satellites. To evaluate the suitability of In{sub 1-x}Ga{sub x}N as a material for space applications, high quality thin films were grown with molecular beam epitaxy and extensive damage testing with electron, proton, and alpha particle radiation was performed. Using the room temperature photoluminescence intensity as a indirect measure of minority carrier lifetime, it is shown that In{sub 1-x}Ga{sub x}N retains its optoelectronic properties at radiation damage doses at least 2 orders of magnitude higher than the damage thresholds of the materials (GaAs and GaInP) currently used in high efficiency MJ cells. This indicates that the In{sub 1-x}Ga{sub x}N is well-suited for the future development of ultra radiation-hard optoelectronics. Critical issues affecting development of solar cells using this material system were addressed. The presence of an electron-rich surface layer in InN and In{sub 1-x}Ga{sub x}N (0 < x < 0.63) was investigated; it was shown that this is a less significant effect at large x. Evidence of p-type activity below the surface in Mg-doped InN was obtained; this is a significant step toward achieving photovoltaic action and, ultimately, a solar cell using this material.

  18. Solar radiation on variously oriented sloping surfaces

    SciTech Connect (OSTI)

    Gopinathan, K.K. )

    1991-01-01

    Monthly average daily irradiation on surfaces tilted towards the equator and also inclined at various azimuth angles are estimated for two locations in Lesotho and the results are presented. The isotropic model suggested by Liu and Jordan (Trans. of Ashrae, 526, 1962) along with the modified equation of Klein (Solar Energy, 19, 4, 1977) are employed for the estimation purposes. Surface orientations are selected at three inclinations for six different azimuth angles. Conclusions are reached for optimum tilt and orientation for summer, winter and annual collection. Total annual radiation values are computed for all the slopes and orientations.

  19. Simulation of solar radiative transfer in cumulus clouds

    SciTech Connect (OSTI)

    Zuev, V.E.; Titov, G.A.

    1996-04-01

    This work presents a 3-D model of radiative transfer which is used to study the relationship between the spatial distribution of cumulus clouds and fluxes (albedo and transmittance) of visible solar radiation.

  20. A 2D Radiation Transport Package with Mimetic Diffusion for ExaFlag...

    Office of Scientific and Technical Information (OSTI)

    A 2D Radiation Transport Package with Mimetic Diffusion for ExaFlag Citation Details In-Document Search Title: A 2D Radiation Transport Package with Mimetic Diffusion for ExaFlag ...

  1. A 2D Radiation Transport Package with Mimetic Diffusion for ExaFlag...

    Office of Scientific and Technical Information (OSTI)

    A 2D Radiation Transport Package with Mimetic Diffusion for ExaFlag Citation Details In-Document Search Title: A 2D Radiation Transport Package with Mimetic Diffusion for ExaFlag...

  2. The Effect of Gas Absorption on the Scattered Radiation in the...

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

    Gas Absorption on the Scattered Radiation in the Solar Almucantar: Results of Numerical ... albedo) from diffuse and direct radiation measured in the solar almucantar has ...

  3. Amorphous silicon passivated contacts for diffused junction silicon solar cells

    SciTech Connect (OSTI)

    Bullock, J. Yan, D.; Wan, Y.; Cuevas, A.; Demaurex, B.; Hessler-Wyser, A.; De Wolf, S.

    2014-04-28

    Carrier recombination at the metal contacts is a major obstacle in the development of high-performance crystalline silicon homojunction solar cells. To address this issue, we insert thin intrinsic hydrogenated amorphous silicon [a-Si:H(i)] passivating films between the dopant-diffused silicon surface and aluminum contacts. We find that with increasing a-Si:H(i) interlayer thickness (from 0 to 16?nm) the recombination loss at metal-contacted phosphorus (n{sup +}) and boron (p{sup +}) diffused surfaces decreases by factors of ?25 and ?10, respectively. Conversely, the contact resistivity increases in both cases before saturating to still acceptable values of ? 50 m? cm{sup 2} for n{sup +} and ?100 m? cm{sup 2} for p{sup +} surfaces. Carrier transport towards the contacts likely occurs by a combination of carrier tunneling and aluminum spiking through the a-Si:H(i) layer, as supported by scanning transmission electron microscopyenergy dispersive x-ray maps. We explain the superior contact selectivity obtained on n{sup +} surfaces by more favorable band offsets and capture cross section ratios of recombination centers at the c-Si/a-Si:H(i) interface.

  4. Spectral Solar Radiation Data Base at NREL

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

    *In September 1991 the Solar Energy Research Institute became the National Renewable Energy Laboratory. [Description taken from http://rredc.nrel.gov/solar/old_data/spectral/

  5. Radiation damage of GaAs thin-film solar cells on Si substrates

    SciTech Connect (OSTI)

    Itoh, Y.; Yamaguchi, M.; Nishioka, T.; Yamamoto, A.

    1987-01-15

    1-MeV electron irradiation damages in GaAs thin-film solar cells on Si substrates are examined for the first time. Damage constant for minority-carrier diffusion length in GaAs heteroepitaxial films on Si substrates is found to be the same as that in GaAs homoepitaxial films on GaAs substrates. This agreement suggests that GaAs/Si has the same defect introduction rate with radiation as GaAs/GaAs. The degradation of GaAs solar cells on Si with electron irradiation is less than that of GaAs solar cells on GaAs, because in the present, GaAs films on Si substrates have lower minority-carrier diffusion length compared to GaAs films on GaAs and these films are insensitive to radiation. The p/sup +/-p/sup +/-n AlGaAs-GaAs heteroface solar cell with junction depth of about 0.3 ..mu..m is concluded to be useful for a high-efficiency and radiation-resistant solar cell fabricated on a Si substrate.

  6. Solar and Photovoltaic Data from the University of Oregon Solar Radiation Monitoring Laboratory (UO SRML)

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

    The UO SRML is a regional solar radiation data center whose goal is to provide sound solar resource data for planning, design, deployment, and operation of solar electric facilities in the Pacific Northwest. The laboratory has been in operation since 1975. Solar data includes solar resource maps, cumulative summary data, daily totals, monthly averages, single element profile data, parsed TMY2 data, and select multifilter radiometer data. A data plotting program and other software tools are also provided. Shade analysis information and contour plots showing the effect of tilt and orientation on annual solar electric system perfomance make up a large part of the photovoltaics data.(Specialized Interface)

  7. Denoising solar radiation data using coiflet wavelets

    SciTech Connect (OSTI)

    Karim, Samsul Ariffin Abdul Janier, Josefina B. Muthuvalu, Mohana Sundaram; Hasan, Mohammad Khatim; Sulaiman, Jumat; Ismail, Mohd Tahir

    2014-10-24

    Signal denoising and smoothing plays an important role in processing the given signal either from experiment or data collection through observations. Data collection usually was mixed between true data and some error or noise. This noise might be coming from the apparatus to measure or collect the data or human error in handling the data. Normally before the data is use for further processing purposes, the unwanted noise need to be filtered out. One of the efficient methods that can be used to filter the data is wavelet transform. Due to the fact that the received solar radiation data fluctuates according to time, there exist few unwanted oscillation namely noise and it must be filtered out before the data is used for developing mathematical model. In order to apply denoising using wavelet transform (WT), the thresholding values need to be calculated. In this paper the new thresholding approach is proposed. The coiflet2 wavelet with variation diminishing 4 is utilized for our purpose. From numerical results it can be seen clearly that, the new thresholding approach give better results as compare with existing approach namely global thresholding value.

  8. Big Data Projects on Solar Tech Evolution and Diffusion | Department of

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

    Energy Big Data Projects on Solar Tech Evolution and Diffusion Big Data Projects on Solar Tech Evolution and Diffusion This is the meeting agenda from the Big Data Projects on Solar Technology Evolution and Diffusion kickoff meeting, held on July 15, 2013 in Arlington, VA and facilitated by the SunShot Initiative. seeds_agenda.pdf (187.28 KB) More Documents & Publications 2014 SunShot Initiative Soft Costs Subprogram Overview The New Science of Soft Costs Breakout Session Flier Download

  9. National Solar Radiation Database 1991-2005 Update: User's Manual

    SciTech Connect (OSTI)

    Wilcox, S.

    2007-04-01

    This manual describes how to obtain and interpret the data products from the updated 1991-2005 National Solar Radiation Database (NSRDB). This is an update of the original 1961-1990 NSRDB released in 1992.

  10. National Solar Radiation Database 1991-2010 Update: User's Manual

    SciTech Connect (OSTI)

    Wilcox, S. M.

    2012-08-01

    This user's manual provides information on the updated 1991-2010 National Solar Radiation Database. Included are data format descriptions, data sources, production processes, and information about data uncertainty.

  11. NREL Updates Solar Radiation Database - News Releases | NREL

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

    Updates Solar Radiation Database November 27, 2012 The U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) and collaborators released a 20-year updated version of the U.S. National Solar Radiation Database, a web-based technical report that provides critical information about solar and meteorological data for 1,454 locations in the U.S. and its territories. The updated database covers 1991-2010 and includes data from 2006-2010 for the first time. It also features

  12. Progress Toward an Updated National Solar Radiation Data Base

    SciTech Connect (OSTI)

    Wilcox, S.; Anderberg, M.; George, R.; Marion, W.; Myers, D.; Renne, D.; Beckman, W.; DeGaetano, A.; Gueymard, C.; Perez, R.; Plantico, M.; Stackhouse, P.; Vignola, F.

    2005-01-01

    Progress is reported on an updated National Solar Radiation Database (NSRDB). Focus on this year's work was on preparing a test-year database for evaluating several solar radiation models that could be used to replace the METSTAT model used in the original 1961-1990 NSRDB. That model is no longer compatible with cloud observations reported by the National Weather Service. We have also included a satellite-based model that will increase the spatial resolution of solar radiation for GIS or mapping applications. Work also included development of improved estimates for aerosols, water vapor, and ozone. High-quality solar measurements were obtained for 33 sites near National Weather Service stations, and model runs were completed for test years 1999 and 2000.

  13. Solar interior and atmosphere

    SciTech Connect (OSTI)

    Cox, A.N.; Livingston, W.C.; Matthews, M.S. National Solar Observatory, Tucson, AZ )

    1991-01-01

    The present work discusses nuclear energy generation in the solar interior, solar neutrino experiments, solar premain-sequence evolution, the computation of standard solar models, radiative-zone mixing, solar element separation by atomic diffusion, the observation and theory of solar oscillations, the solar internal rotation and magnetism implications of oscillations, solar gravity modes, and solar oscillation-mode excitation. Also discussed are the solar spectrum, the role of the solar photosphere and a radiative boundary, high spatial-resolution techniques for solar study, high-resolution observations of the solar granulation, large-scale velocity fields, the solar activity cycle, the magnetic fields of active regions and sunspots, the physics of flux tubes and filigrees, the heating of the solar chromosphere, the fine structure of the solar transition region, coronal activity, the coronal origins of the solar winds, and postmain sequence solar evolution.

  14. How to diffuse solar innovations to US consumers. Part II of a series

    SciTech Connect (OSTI)

    Shama, A.

    1982-09-01

    The social change perspective and diffusion perspective of solar energy are discussed. Discussions on product price, promotion, and distribution of renewable energy systems are presented. The conclusions and recommendations are: (1) develop and perfect solar energy products; (2) define solar energy products carefully; (3) rely on relative advantage of solar energy innovations; (4) demonstrate solar energy innovations; (5) target solar energy innovations; (6) introduce regional policies; (7) help the consumer decision-making process; (8) consider the do-it-yourself market; (9) reward the use of solar energy innovations; (10) offer financial services; (11) ensure realistic price comparisons; (12) use penetration price policy; (13) ensure appropriate distribution; (14) discourage energy inefficient practices; (15) promote the use of solar; (16) use flexible mandates. (MJF)

  15. Incorporating photon recycling into the analytical drift-diffusion model of high efficiency solar cells

    SciTech Connect (OSTI)

    Lumb, Matthew P.; Steiner, Myles A.; Geisz, John F.; Walters, Robert J.

    2014-11-21

    The analytical drift-diffusion formalism is able to accurately simulate a wide range of solar cell architectures and was recently extended to include those with back surface reflectors. However, as solar cells approach the limits of material quality, photon recycling effects become increasingly important in predicting the behavior of these cells. In particular, the minority carrier diffusion length is significantly affected by the photon recycling, with consequences for the solar cell performance. In this paper, we outline an approach to account for photon recycling in the analytical Hovel model and compare analytical model predictions to GaAs-based experimental devices operating close to the fundamental efficiency limit.

  16. Sensitivity of Clear-Sky Diffuse Radiation to In Situ Aerosol Scattering Parameters

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

    Sensitivity of Clear-Sky Diffuse Radiation to In Situ Aerosol Scattering Parameters P. J. Ricchiazzi and C. Gautier University of California Santa Barbara, California Introduction Recent studies of clear-sky radiation indicate that current radiative transfer (RT) models underestimate atmospheric absorption when standard aerosol properties are used. This so-called clear-sky anomaly is manifested in predicted levels of diffuse radiation significantly below those observed at Southern Great Plains

  17. Curve fitting methods for solar radiation data modeling

    SciTech Connect (OSTI)

    Karim, Samsul Ariffin Abdul E-mail: balbir@petronas.com.my; Singh, Balbir Singh Mahinder E-mail: balbir@petronas.com.my

    2014-10-24

    This paper studies the use of several type of curve fitting method to smooth the global solar radiation data. After the data have been fitted by using curve fitting method, the mathematical model of global solar radiation will be developed. The error measurement was calculated by using goodness-fit statistics such as root mean square error (RMSE) and the value of R{sup 2}. The best fitting methods will be used as a starting point for the construction of mathematical modeling of solar radiation received in Universiti Teknologi PETRONAS (UTP) Malaysia. Numerical results indicated that Gaussian fitting and sine fitting (both with two terms) gives better results as compare with the other fitting methods.

  18. Modeling and Analysis of Solar Radiation Potentials on Building Rooftops

    SciTech Connect (OSTI)

    Omitaomu, Olufemi A; Kodysh, Jeffrey B; Bhaduri, Budhendra L

    2012-01-01

    The active application of photovoltaic for electricity generation could effectively transform neighborhoods and commercial districts into small, localized power plants. This application, however, relies heavily on an accurate estimation of the amount of solar radiation that is available on individual building rooftops. While many solar energy maps exist at higher spatial resolution for concentrated solar energy applications, the data from these maps are not suitable for roof-mounted photovoltaic for several reasons, including lack of data at the appropriate spatial resolution and lack of integration of building-specific characteristics into the models used to generate the maps. To address this problem, we have developed a modeling framework for estimating solar radiation potentials on individual building rooftops that is suitable for utility-scale applications as well as building-specific applications. The framework uses light detection and ranging (LIDAR) data at approximately 1-meter horizontal resolution and 0.3-meter vertical resolution as input for modeling a large number of buildings quickly. One of the strengths of this framework is the ability to parallelize its implementation. Furthermore, the framework accounts for building specific characteristics, such as roof slope, roof aspect, and shadowing effects, that are critical to roof-mounted photovoltaic systems. The resulting data has helped us to identify the so-called solar panel sweet spots on individual building rooftops and obtain accurate statistics of the variation in solar radiation as a function of time of year and geographical location.

  19. Progress on an Updated National Solar Radiation Data Base: Preprint

    SciTech Connect (OSTI)

    Wilcox, S.; Anderberg, M.; George, R.; Marion, W.; Myers, D.; Renne, D.; Beckman, W.; DeGaetano, A.; Gueymard, C.; Perez, R.; Plantico, M.; Stackhouse, P.; Vignola, F.

    2004-03-01

    In 1992, The National Renewable Energy Laboratory (NREL) released the 1961-1990 National Solar Radiation Data Base (NSRDB), a 30-year set of hourly solar radiation data. In April 2003, NREL convened a meeting of experts to investigate issues concerning a proposed update of the NSRDB. The panel determined that an important difficulty posed by the update was the shift from manual to automated cloud observations at National Weather Service stations in the United States. The solar model used in the original NSRDB relied heavily on the methodology and resolution of the manual cloud observations. The meeting participants recommended that NREL produce a plan for creating an update using currently available meteorological observations and satellite imagery. This paper describes current progress toward a plan for an updated NSRDB.

  20. NREL: MIDC/University of Texas Panamerican Solar Radiation Lab (26.49 N,

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

    98.17 W, 45 m, GMT-6) University of Texas Panamerican (UTPA) Solar Radiation Lab (SRL)

  1. Placement and efficiency effects on radiative forcing of solar installations

    SciTech Connect (OSTI)

    Burg, Brian R.; Ruch, Patrick; Paredes, Stephan; Michel, Bruno

    2015-09-28

    The promise for harnessing solar energy being hampered by cost, triggered efforts to reduce them. As a consequence low-efficiency, low-cost photovoltaics (PV) panels prevail. Conversely, in the traditional energy sector efficiency is extremely important due to the direct costs associated to fuels. This also affects solar energy due to the radiative forcing caused by the dark solar panels. In this paper we extend the concept of energy payback time by including the effect of albedo change, which gives a better assessment of the system sustainability. We present an analysis on the short and medium term climate forcing effects of different solar collectors in Riyadh, Saudi Arabia and demonstrate that efficiency is important to reduce the collector area and cost. This also influences the embodied energy and the global warming potential. We show that a placement of a high concentration photovoltaic thermal solar power station outside of the city using a district cooling system has a double beneficial effect since it improves the solar conversion efficiency and reduces the energy demand for cooling in the city. We also explain the mechanisms of the current economic development of solar technologies and anticipate changes.

  2. University of Texas Panamerican (UTPA): Solar Radiation Lab (SRL); Edinburg, Texas (Data)

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

    Ramos, J.; Andreas, A.

    2011-09-01

    This measurement station monitors global horizontal, direct normal, and diffuse horizontal irradiance to define the amount of solar energy that hits this particular location.

  3. University of Texas Panamerican (UTPA): Solar Radiation Lab (SRL); Edinburg, Texas (Data)

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

    Ramos, J.; Andreas, A.

    This measurement station monitors global horizontal, direct normal, and diffuse horizontal irradiance to define the amount of solar energy that hits this particular location.

  4. Visual-SOLAR: Modeling and Visualization of Solar Radiation Potential on Individual Building Rooftops

    Energy Science and Technology Software Center (OSTI)

    2013-05-01

    We have developed a modeling framework for estimating solar radiation potentials on individual building rooftops that is suitable for utility-scale applications as well as building-specific applications. The framework uses light detection and ranging (LIDAR) data at approximately 1-meter horizontal resolution and 0.3-meter vertical resolution as input for modeling a large number of buildings quickly. One of the strengths of this framework is the ability to parallelize its implementation. Furthermore, the framework accounts for building specificmore » characteristics, such as roof slope, roof aspect, and shadowing effects, that are critical to roof-mounted photovoltaic system. The resulting data has helped us to identify the so-called "solar panel sweet spots" on individual building rooftops and obtain accurate statistics of the variation in solar radiation as a function of time of year and geographical location.« less

  5. Visual-SOLAR: Modeling and Visualization of Solar Radiation Potential on Individual Building Rooftops

    SciTech Connect (OSTI)

    2013-05-01

    We have developed a modeling framework for estimating solar radiation potentials on individual building rooftops that is suitable for utility-scale applications as well as building-specific applications. The framework uses light detection and ranging (LIDAR) data at approximately 1-meter horizontal resolution and 0.3-meter vertical resolution as input for modeling a large number of buildings quickly. One of the strengths of this framework is the ability to parallelize its implementation. Furthermore, the framework accounts for building specific characteristics, such as roof slope, roof aspect, and shadowing effects, that are critical to roof-mounted photovoltaic system. The resulting data has helped us to identify the so-called "solar panel sweet spots" on individual building rooftops and obtain accurate statistics of the variation in solar radiation as a function of time of year and geographical location.

  6. MAGNETIC TRANSPORT ON THE SOLAR ATMOSPHERE BY LAMINAR AND TURBULENT AMBIPOLAR DIFFUSION

    SciTech Connect (OSTI)

    Hiraki, Y. [National Institute for Fusion Science (NIFS), Toki, Gifu (Japan); Krishan, V. [Raman Research Institute, Bangalore 560 080 (India); Masuda, S., E-mail: hiraki.yasutaka@nifs.ac.j [Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, Aichi (Japan)

    2010-09-10

    The lower solar atmosphere consists of partially ionized turbulent plasmas harboring velocity field, magnetic field, and current density fluctuations. The correlations among these small-scale fluctuations give rise to large-scale flows and magnetic fields which decisively affect all transport processes. The three-fluid system consisting of electrons, ions, and neutral particles supports nonideal effects such as the Hall effect and ambipolar diffusion. Here, we study magnetic transport by the laminar- and turbulent-scale ambipolar diffusion processes using a simple model of the magnetic induction equation. Based on a linear analysis of the induction equation, we perform a one-dimensional numerical simulation to study the laminar ambipolar effect on medium-scale magnetic field structures. The nonlinearity of the laminar ambipolar diffusion creates magnetic structures with sharp gradients in the scale of hundreds of kilometers. We expect that these can be amenable to processes such as magnetic reconnection and energy release therefrom for heating and flaring of the solar plasma. Analyzing the characteristic timescales of these processes, we find that the turbulent diffusion timescale is smaller by several orders of magnitude than the laminar diffusion timescale. The effect of the modeled turbulent ambipolar diffusion on the obtained field structures is briefly discussed.

  7. Data From HANE-Generated Radiation Belts and the Origin of Diffusion Theory

    SciTech Connect (OSTI)

    Winske, Dan

    2012-07-16

    In this presentation we briefly review some of the published data regarding the artificial radiation belts produced by the Starfish and R2 high altitude nuclear explosions in 1962. The data showed slow temporal variations of the belts in altitude (L) and pitch angle ({alpha}) that could be modeled as a diffusion process. That early work formed the basis for more complex radiation belt diffusion models that are in use at present.

  8. Prediction of Solar Radiation on Building Rooftops: A Data-Mining Approach

    SciTech Connect (OSTI)

    Omitaomu, Olufemi A; Bhaduri, Budhendra L; Kodysh, Jeffrey B

    2012-01-01

    Solar energy technologies offer a clean, renewable, and domestic energy source, and are essential components of a sustainable energy future. The accurate measurement of solar radiation data is essential for optimum site selection of future distributed solar power plants as well as sizing photovoltaic systems. However, solar radiation data are not readily available because measured sequences of radiation values are obtained for a few locations in a country. When the data are available, they are usually at different time periods and spatial scale. The availability of solar radiation data at hourly or daily time scale will enhance the integration of solar energy into electricity generation and promote a sustainable energy future. The ability to generate approximate solar radiation values is often the only practical way to obtain radiation data at hourly or daily time scale. As a result, several models have been developed for estimating solar radiation values based on analytical, numerical simulation, and statistical approaches. However, these models have inherent challenges. We will discuss some of those challenges in this paper. To enhance the prediction of solar radiation values, a novel approach is presented for estimating solar radiation values using support vector machine technique. The approach accounts for unique characteristics that influence solar radiation values. The preliminary results obtained offer useful insights for model enhancements.

  9. Diffusion-Reaction Modeling of Cu Migration in CdTe Solar Devices

    SciTech Connect (OSTI)

    Guo, Da; Brinkman, Daniel; Fang, Tian; Akis, Richard; Sankin, Igor; Vasileska, Dragica; Ringhofer, Christian

    2015-09-04

    In this work, we report on development of one-dimensional (1D) finite-difference and two-dimensional (2D) finite-element diffusion-reaction simulators to investigate mechanisms behind Cu-related metastabilities observed in CdTe solar cells [1]. The evolution of CdTe solar cells performance has been studied as a function of stress time in response to the evolution of associated acceptor and donor states. To achieve such capability, the simu-lators solve reaction-diffusion equations for the defect states in time-space domain self-consistently with the free carrier transport. Re-sults of 1-D and 2-D simulations have been compared to verify the accuracy of solutions.

  10. Solar Radiation Monitoring Station (SoRMS): Humboldt State University, Arcata, California (Data)

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

    Wilcox, S.; Andreas, A.

    2007-05-02

    A partnership with HSU and U.S. Department of Energy's National Renewable Energy Laboratory (NREL) to collect solar data to support future solar power generation in the United States. The measurement station monitors global horizontal, direct normal, and diffuse horizontal irradiance to define the amount of solar energy that hits this particular location.

  11. Solar Radiation Monitoring Station (SoRMS): Humboldt State University, Arcata, California (Data)

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

    Wilcox, S.; Andreas, A.

    A partnership with HSU and U.S. Department of Energy's National Renewable Energy Laboratory (NREL) to collect solar data to support future solar power generation in the United States. The measurement station monitors global horizontal, direct normal, and diffuse horizontal irradiance to define the amount of solar energy that hits this particular location.

  12. National Solar Radiation Data Bases (NSRDB): 1961 to 1990 and 1991 to 2005

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

    The National Solar Radiation Data Base 1961-1990 (NSRDB) contains 30 years of solar radiation and supplementary meteorological data from 237 NWS sites in the U.S., plus sites in Guam and Puerto Rico. The updated 1991-2005 National Solar Radiation Database holds solar and meteorological data for 1,454 locations in the United States and its territories. See also the interactive data maps for the 1961 to 1990 data at http://rredc.nrel.gov/solar/old_data/nsrdb/1961-1990/redbook/atlas/.

  13. Study of minority carrier diffusion lengths in photoactive layers of multijunction solar cells

    SciTech Connect (OSTI)

    Mintairov, S. A. Andreev, V. M.; Emelyanov, V. M.; Kalyuzhnyy, N. A.; Timoshina, N. K.; Shvarts, M. Z.; Lantratov, V. M.

    2010-08-15

    A technique for determining a minority carrier's diffusion length in photoactive III-V layers of solar cells by approximating their spectral characteristics is presented. Single-junction GaAs, Ge and multi-junction GaAs/Ge, GaInP/GaAs, and GaInP/GaInAs/Ge solar cells fabricated by hydride metal-organic vapor-phase epitaxy (H-MOVPE) have been studied. The dependences of the minority carrier diffusion length on the doping level of p-Ge and n-GaAs are determined. It is shown that the parameters of solid-state diffusion of phosphorus atoms to the p-Ge substrate from the n-GaInP nucleation layer are independent of the thickness of the latter within 35-300 nm. It is found that the diffusion length of subcells of multijunction structures in Ga(In)As layers is smaller in comparison with that of single-junction structures.

  14. Ultra-low-frequency wave-driven diffusion of radiation belt relativistic electrons

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

    Su, Zhenpeng; Zhu, Hui; Xiao, Fuliang; Zong, Q. -G.; Zhou, X. -Z.; Zheng, Huinan; Wang, Yuming; Wang, Shui; Hao, Y. -X.; Gao, Zhonglei; et al

    2015-12-22

    The Van Allen radiation belts are typically two zones of energetic particles encircling the Earth separated by the slot region. How the outer radiation belt electrons are accelerated to relativistic energies remains an unanswered question. Recent studies have presented compelling evidence for the local acceleration by very-low-frequency (VLF) chorus waves. However, there has been a competing theory to the local acceleration, radial diffusion by ultra-low-frequency (ULF) waves, whose importance has not yet been determined definitively. Here we report a unique radiation belt event with intense ULF waves but no detectable VLF chorus waves. So, our results demonstrate that the ULFmore » waves moved the inner edge of the outer radiation belt earthward 0.3 Earth radii and enhanced the relativistic electron fluxes by up to one order of magnitude near the slot region within about 10 h, providing strong evidence for the radial diffusion of radiation belt relativistic electrons.« less

  15. Ultra-low-frequency wave-driven diffusion of radiation belt relativistic electrons

    SciTech Connect (OSTI)

    Su, Zhenpeng; Zhu, Hui; Xiao, Fuliang; Zong, Q. -G.; Zhou, X. -Z.; Zheng, Huinan; Wang, Yuming; Wang, Shui; Hao, Y. -X.; Gao, Zhonglei; He, Zhaoguo; Baker, D. N.; Spence, H. E.; Reeves, G. D.; Blake, J. B.; Wygant, J. R.

    2015-12-22

    The Van Allen radiation belts are typically two zones of energetic particles encircling the Earth separated by the slot region. How the outer radiation belt electrons are accelerated to relativistic energies remains an unanswered question. Recent studies have presented compelling evidence for the local acceleration by very-low-frequency (VLF) chorus waves. However, there has been a competing theory to the local acceleration, radial diffusion by ultra-low-frequency (ULF) waves, whose importance has not yet been determined definitively. Here we report a unique radiation belt event with intense ULF waves but no detectable VLF chorus waves. So, our results demonstrate that the ULF waves moved the inner edge of the outer radiation belt earthward 0.3 Earth radii and enhanced the relativistic electron fluxes by up to one order of magnitude near the slot region within about 10 h, providing strong evidence for the radial diffusion of radiation belt relativistic electrons.

  16. Chapter 1.12: Solar Radiation Resource Assessment for Renewable Energy Conversion

    SciTech Connect (OSTI)

    Myers, D. R.

    2012-01-01

    This chapter addresses measurements, modeling, and databases of solar energy potential that may serve as fuel for solar energy conversion systems. Developing innovative designs for capturing and converting solar radiation is only one part of the equation for solar system deployment. Identifying, locating, and prospecting for the appropriate quantity and quality of solar resources to fuel these systems is critical to system designers, investors, financial backers, utilities, governments, and owner/operators. This chapter addresses the fundamentals and state of the art for measuring, modeling, and applying solar radiation resource data to meet decision-making needs.

  17. Validation of the National Solar Radiation Database (NSRDB) ...

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

    To be presented at the European PV Solar Energy Conference and Exhibition Hamburg, ... satellite-based solar resource data is foundational and critical to solar ...

  18. Radiation response of multi-quantum well solar cells: Electron-beam-induced current analysis

    SciTech Connect (OSTI)

    Maximenko, S. I. Scheiman, D. A.; Jenkins, P. P.; Walters, R. J.; Lumb, M. P.; Hoheisel, R.; Gonzalez, M.; Messenger, S. R.; Tibbits, T. N. D.; Imaizumi, M.; Ohshima, T.; Sato, S. I.

    2015-12-28

    Solar cells utilizing multi-quantum well (MQW) structures are considered promising candidate materials for space applications. An open question is how well these structures can resist the impact of particle irradiation. The aim of this work is to provide feedback about the radiation response of In{sub 0.01}Ga{sub 0.99}As solar cells grown on Ge with MQWs incorporated within the i-region of the device. In particular, the local electronic transport properties of the MQW i-regions of solar cells subjected to electron and proton irradiation were evaluated experimentally using the electron beam induced current (EBIC) technique. The change in carrier collection distribution across the MQW i-region was analyzed using a 2D EBIC diffusion model in conjunction with numerical modeling of the electrical field distribution. Both experimental and simulated findings show carrier removal and type conversion from n- to p-type in MQW i-region at a displacement damage dose as low as ∼6.06–9.88 × 10{sup 9} MeV/g. This leads to a redistribution of the electric field and significant degradation in charge carrier collection.

  19. Radiation Dry Bias in the TWP-ICE Radiosonde Soundings Solar...

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

    Radiation Dry Bias in the TWP-ICE Radiosonde Soundings Solar Zenith Angle Correction ... used in TWP-ICE, is known to be affected by a significant day-time radiation dry bias. ...

  20. GaAs quantum dot solar cell under concentrated radiation

    SciTech Connect (OSTI)

    Sablon, K.; Little, J. W.; Hier, H.; Li, Y.; Mitin, V.; Vagidov, N.; Sergeev, A.

    2015-08-17

    Effects of concentrated solar radiation on photovoltaic performance are investigated in well-developed GaAs quantum dot (QD) solar cells with 1-Sun efficiencies of 18%–19%. In these devices, the conversion processes are enhanced by nanoscale potential barriers and/or AlGaAs atomically thin barriers around QDs, which prevent photoelectron capture to QDs. Under concentrated radiation, the short circuit current increases proportionally to the concentration and the open circuit voltage shows the logarithmic increase. In the range up to hundred Suns, the contributions of QDs to the photocurrent are proportional to the light concentration. The ideality factors of 1.1–1.3 found from the V{sub OC}-Sun characteristics demonstrate effective suppression of recombination processes in barrier-separated QDs. The conversion efficiency shows the wide maximum in the range of 40–90 Suns and reaches 21.6%. Detailed analysis of I-V-Sun characteristics shows that at low intensities, the series resistance decreases inversely proportional to the concentration and, at ∼40 Suns, reaches the plateau determined mainly by the front contact resistance. Improvement of contact resistance would increase efficiency to above 24% at thousand Suns.

  1. Notice of Intent to Issue Solar Energy Evolution and Diffusion Studies II- State Energy Strategies (SEEDSII-SES)

    Broader source: Energy.gov [DOE]

    The SunShot Initiative intends to release a funding opportunity announcement (FOA) that will address the soft costs of solar energy. The Solar Energy Evolution and Diffusion Studies II - State Energy Strategies (SEEDSII-SES) funding opportunity announcement will contain two topics.

  2. Broken-cloud enhancement of solar radiation absorption

    SciTech Connect (OSTI)

    Byrne, R.N.; Somerville, R.C.; Subasilar, B.

    1996-04-01

    Two papers recently published in Science have shown that there is more absorption of solar radiation than estimated by current atmospheric general circulation models (GCMs) and that the discrepancy is associated with cloudy scenes. We have devised a simple model which explains this as an artifact of stochastic radiative transport. We first give a heuristic description, unencumbered by mathematical detail. Consider a simple case with clouds distributed at random within a single level whose upper and lower boundaries are fixed. The solar zenith angle is small to moderate; this is therefore an energetically important case. Fix the average areal liquid water content of the cloud layer, and take the statistics of the cloud distribution to be homogeneous within the layer. Furthermore, assume that all the clouds in the layer have the same liquid water content, constant throughout the cloud, and that apart from their droplet content they are identical to the surrounding clear sky. Let the clouds occupy on the average a fraction p{sub cld} of the volume of the cloudy layer, and let them have a prescribed distribution of sizes about some mean. This is not a fractal distribution, because it has a scale. Cloud shape is unimportant so long as cloud aspect ratios are not far from unity. Take the single-scattering albedo to be unity for the droplets in the clouds. All of the absorption is due to atmospheric gases, so the absorption coefficient at a point is the same for cloud and clear sky. Absorption by droplets is less than 10% effect in the numerical stochastic radiation calculations described below, so it is reasonable to neglect it at this level of idealization.

  3. Solar Circuitry

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

    Solar Circuitry" with the Solar Powered Energy Kit Curriculum: Solar Power- (lightelectromagnetic radiation, electricity, circuitry, efficiency, energy transformation, subatomic ...

  4. Laplace plane modifications arising from solar radiation pressure

    SciTech Connect (OSTI)

    Rosengren, Aaron J.; Scheeres, Daniel J.

    2014-05-01

    The dynamical effects of solar radiation pressure (SRP) in the solar system have been rigorously studied since the early 1900s. This non-gravitational perturbation plays a significant role in the evolution of dust particles in circumplanetary orbits, as well as in the orbital motion about asteroids and comets. For gravitationally dominated orbits, SRP is negligible and the resulting motion is largely governed by the oblateness of the primary and the attraction of the Sun. The interplay between these gravitational perturbations gives rise to three mutually perpendicular planes of equilibrium for circular satellite orbits. The classical Laplace plane lies between the equatorial and orbital planes of the primary, and is the mean reference plane about whose axis the pole of a satellite's orbit precesses. From a previously derived solution for the secular motion of an orbiter about a small body in a SRP dominated environment, we find that SRP acting alone will cause an initially circular orbit to precess around the pole of the primary's heliocentric orbital plane. When the gravitational and non-gravitational perturbations act in concert, the resulting equilibrium planes turn out to be qualitatively different, in some cases, from those obtained without considering the radiation pressure. The warping of the surfaces swept out by the modified equilibria as the semi-major axis varies depends critically on the cross-sectional area of the body exposed. These results, together with an adiabatic invariance argument on Poynting-Robertson drag, provide a natural qualitative explanation for the initial albedo dichotomy of Saturn's moon, Iapetus.

  5. Study of global daily solar radiation and its relation to sunshine duration in Bahrain

    SciTech Connect (OSTI)

    Al-Sadah, F.H.; Ragab, F.M. )

    1991-01-01

    The regression coefficients a and b of Angstrom type correlation for the monthly daily average global solar radiation have been determined. The two constants a and b have been derived for different months during the period 1983-1987. The clearness index (H/H{sub 0}) based on predicted and measured values of global daily solar radiation is presented for different seasons of the year. The study depicts the various astronomical and meteorological parameters affecting the global radiation in Bahrain.

  6. Differences in Brainstem Fiber Tract Response to Radiation: A Longitudinal Diffusion Tensor Imaging Study

    SciTech Connect (OSTI)

    Uh, Jinsoo; Merchant, Thomas E.; Li, Yimei; Feng, Tianshu; Gajjar, Amar; Ogg, Robert J.; Hua, Chiaho

    2013-06-01

    Purpose: To determine whether radiation-induced changes in white matter tracts are uniform across the brainstem. Methods and Materials: We analyzed serial diffusion tensor imaging data, acquired before radiation therapy and over 48 to 72 months of follow-up, from 42 pediatric patients (age 6-20 years) with medulloblastoma. FSL software (FMRIB, Oxford, UK) was used to calculate fractional anisotropy (FA) and axial, radial, and mean diffusivities. For a consistent identification of volumes of interest (VOIs), the parametric maps of each patient were transformed to a standard brain space (MNI152), on which we identified VOIs including corticospinal tract (CST), medial lemniscus (ML), transverse pontine fiber (TPF), and middle cerebellar peduncle (MCP) at the level of pons. Temporal changes of DTI parameters in VOIs were compared using a linear mixed effect model. Results: Radiation-induced white matter injury was marked by a decline in FA after treatment. The decline was often accompanied by decreased axial diffusivity, increased radial diffusivity, or both. This implied axonal damage and demyelination. We observed that the magnitude of the changes was not always uniform across substructures of the brainstem. Specifically, the changes in DTI parameters for TPF were more pronounced than in other regions (P<.001 for FA) despite similarities in the distribution of dose. We did not find a significant difference among CST, ML, and MCP in these patients (P>.093 for all parameters). Conclusions: Changes in the structural integrity of white matter tracts, assessed by DTI, were not uniform across the brainstem after radiation therapy. These results support a role for tract-based assessment in radiation treatment planning and determination of brainstem tolerance.

  7. Evaluation of linear interpolation method for missing value on solar radiation dataset in Perlis

    SciTech Connect (OSTI)

    Saaban, Azizan; Zainudin, Lutfi; Bakar, Mohd Nazari Abu

    2015-05-15

    This paper intends to reveal the ability of the linear interpolation method to predict missing values in solar radiation time series. Reliable dataset is equally tends to complete time series observed dataset. The absence or presence of radiation data alters long-term variation of solar radiation measurement values. Based on that change, the opportunities to provide bias output result for modelling and the validation process is higher. The completeness of the observed variable dataset has significantly important for data analysis. Occurrence the lack of continual and unreliable time series solar radiation data widely spread and become the main problematic issue. However, the limited number of research quantity that has carried out to emphasize and gives full attention to estimate missing values in the solar radiation dataset.

  8. Asymptotic diffusion limit of cell temperature discretisation schemes for thermal radiation transport

    SciTech Connect (OSTI)

    Smedley-Stevenson, Richard P.; McClarren, Ryan G.

    2015-04-01

    This paper attempts to unify the asymptotic diffusion limit analysis of thermal radiation transport schemes, for a linear-discontinuous representation of the material temperature reconstructed from cell centred temperature unknowns, in a process known as ‘source tilting’. The asymptotic limits of both Monte Carlo (continuous in space) and deterministic approaches (based on linear-discontinuous finite elements) for solving the transport equation are investigated in slab geometry. The resulting discrete diffusion equations are found to have nonphysical terms that are proportional to any cell-edge discontinuity in the temperature representation. Based on this analysis it is possible to design accurate schemes for representing the material temperature, for coupling thermal radiation transport codes to a cell centred representation of internal energy favoured by ALE (arbitrary Lagrange–Eulerian) hydrodynamics schemes.

  9. Microsoft Word - Construction of Accuracy-Preserving Surrogate for the Eigenvalue Radiation Diffusion and Transport Problem

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

    2 - Advances in Reactor Physics - Linking Research, Industry, and Education Knoxville, Tennessee, USA, April 15-20, 2012, on CD-ROM, American Nuclear Society, LaGrange Park, IL (2012) CONSTRUCTION OF ACCURACY-PRESERVING SURROGATE FOR THE EIGENVALUE RADIATION DIFFUSION AND/OR TRANSPORT PROBLEM Congjian Wang and Hany S. Abdel-Khalik  Department of Nuclear Engineering North Caroline State University Raleigh, NC 27695 cwang21@ncsu.edu ; abdelkhalik@ncsu.edu ABSTRACT The construction of surrogate

  10. Coastal-inland solar radiation difference study. Final report

    SciTech Connect (OSTI)

    Bach, W.D. Jr.; Vukovich, F.M.

    1980-04-01

    The purpose of this study was to quantify the characteristics of solar insolation in the coastal zone and to determine the effect of the sea breeze circulation on the global insolation. In order to satisfy these objectives, a six station sampling network was established in the coastal plain of southeastern North Carolina, where previous evidence has indicated that the sea breeze circulation is almost a daily occurrence from late May through October. Three sites (Sloop Point, Onslow Beach, and Cape Fear Technical Institute (CFTI)) were located near the coast (coastal sites) to assess the insolation at the coast. A site (Clinton) was located in an area seldom affected by the sea breeze (about 100 km from the coast). Two additional sites, Wallace and Ellis Airport, located between the coastal sites and the control site, were to be used to assess the transient impact of the sea breeze upon the insolation. Pyranometers were located at each site to measure the global insolation. Direct normal insolation measured by a pyrheliometer and ultraviolet radiation measured by uv radiometers were observed at the Sloop Point and Clinton sites only. Data were collected during the calendar year 1978. The results of the study indicated that the global insolation had greater variability over the network during the summer season (June, July, and August). During the summer, there was a systematicdiurnal variation of the difference in global insolation between the inland and the coastal sites.

  11. Absorption and scattering of laser radiation by the diffusion flame of aviation kerosene

    SciTech Connect (OSTI)

    Gvozdev, S V; Glova, A F; Dubrovskii, V Yu; Durmanov, S T; Krasyukov, A G; Lysikov, A Yu; Smirnov, G V; Solomakhin, V B

    2012-04-30

    The absorption coefficient of the radiation of a repetitively pulsed Nd : YAG laser with an average output power up to 6 W and of a cw ytterbium optical fibre laser with an output power up to 3 kW was measured in the diffusion flame of aviation kerosene burning on a free surface in the atmospheric air. The absorption coefficient as a function of flame length, radiation power, and radiation intensity, which was varied in the {approx}10{sup 3} - 5 Multiplication-Sign 10{sup 4} W cm{sup -2} range, was obtained for two distances (1 and 2 cm) between the laser beam axis and the surface. The coefficient of radiation absorption by kerosene flame was compared with that in ethanol and kerosene - ethanol mixture flames. The radiation power scattered by a small segment of the kerosene flame irradiated by Nd : YAG laser radiation was measured as a function of longitudinal and azimuthal coordinates. An estimate was made of the total scattered radiation power.

  12. Pitch angle and velocity diffusions of newborn ions by turbulence in the solar wind

    SciTech Connect (OSTI)

    Ziebell, L.F.; Yoon, P.H. )

    1990-12-01

    The present study is dedicated to the analysis of dynamical processes relevant to the interaction of newborn ions with turbulence in the solar wind, when the level of turbulence is moderately low so that quasi-linear theory is applicable. It is assumed that the low-frequency turbulence is at saturation level and not affected by the newborn ions. In order to follow the time evolution of the ion distribution, the quasi-linear diffusion equation is derived and numerically solved, starting from a ring-beam initial distribution. A simplified treatment of the resonance broadening effect is included in the diffusion equation, and its role in the pickup process is discussed. Two different configurations of wave polarization and direction of propagation are considered, using model turbulence spectra. The conditions that lead either to the formation of anisotropic shells as a long-duration transient state or to rapid isotropization of the ion pitch angle distribution are discussed, as well as the conditions leading to significant acceleration of the ions.

  13. Passive-solar directional-radiating cooling system

    DOE Patents [OSTI]

    Hull, J.R.; Schertz, W.W.

    1985-06-27

    A radiative cooling system for use with an ice-making system having a radiating surface aimed at the sky for radiating energy at one or more wavelength bands for which the atmosphere is transparent and a cover thermally isolated from the radiating surface and transparent at least to the selected wavelength or wavelengths, the thermal isolation reducing the formation of condensation on the radiating surface and/or cover and permitting the radiation to continue when the radiating surface is below the dewpoint of the atmosphere, and a housing supporting the radiating surface, cover and heat transfer means to an ice storage reservoir.

  14. Passive-solar directional-radiating cooling system

    DOE Patents [OSTI]

    Hull, John R.; Schertz, William W.

    1986-01-01

    A radiative cooling system for use with an ice-making system having a radiating surface aimed at the sky for radiating energy at one or more wavelength bands for which the atmosphere is transparent and a cover thermally isolated from the radiating surface and transparent at least to the selected wavelength or wavelengths, the thermal isolation reducing the formation of condensation on the radiating surface and/or cover and permitting the radiation to continue when the radiating surface is below the dewpoint of the atmosphere, and a housing supporting the radiating surface, cover and heat transfer means to an ice storage reservoir.

  15. A path to practical Solar Pumped Lasers via Radiative Energy Transfer

    SciTech Connect (OSTI)

    Reusswig, Philip D.; Nechayev, Sergey; Scherer, Jennifer M.; Hwang, Gyu Weon; Bawendi, Moungi G.; Baldo, Marc. A.; Rotschild, Carmel

    2015-10-05

    The optical conversion of incoherent solar radiation into a bright, coherent laser beam enables the application of nonlinear optics to solar energy conversion and storage. Here, we present an architecture for solar pumped lasers that uses a luminescent solar concentrator to decouple the conventional trade-off between solar absorption efficiency and the mode volume of the optical gain material. We report a 750-μm-thick Nd 3+ -doped YAG planar waveguide sensitized by a luminescent CdSe/CdZnS (core/shell) colloidal nanocrystal, yielding a peak cascade energy transfer of 14%, a broad spectral response in the visible portion of the solar spectrum, and an equivalent quasi-CW solar lasing threshold of 23 W-cm-2, or approximately 230 suns. The efficient coupling of incoherent, spectrally broad sunlight in small gain volumes should allow the generation of coherent laser light from intensities of less than 100 suns.

  16. A path to practical Solar Pumped Lasers via Radiative Energy Transfer

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

    Reusswig, Philip D.; Nechayev, Sergey; Scherer, Jennifer M.; Hwang, Gyu Weon; Bawendi, Moungi G.; Baldo, Marc. A.; Rotschild, Carmel

    2015-10-05

    The optical conversion of incoherent solar radiation into a bright, coherent laser beam enables the application of nonlinear optics to solar energy conversion and storage. Here, we present an architecture for solar pumped lasers that uses a luminescent solar concentrator to decouple the conventional trade-off between solar absorption efficiency and the mode volume of the optical gain material. We report a 750-μm-thick Nd 3+ -doped YAG planar waveguide sensitized by a luminescent CdSe/CdZnS (core/shell) colloidal nanocrystal, yielding a peak cascade energy transfer of 14%, a broad spectral response in the visible portion of the solar spectrum, and an equivalent quasi-CWmore » solar lasing threshold of 23 W-cm-2, or approximately 230 suns. The efficient coupling of incoherent, spectrally broad sunlight in small gain volumes should allow the generation of coherent laser light from intensities of less than 100 suns.« less

  17. Solar radiation data manual for flat-plate and concentrating...

    Office of Scientific and Technical Information (OSTI)

    Visit OSTI to utilize additional information resources in energy science and technology. A ... The data in the manual were modeled using hourly values of direct beam and diffuse ...

  18. Analysis of experimental solar radiation data for Rio de Janeiro, Brazil

    SciTech Connect (OSTI)

    Cavalcanti, E.S.C. )

    1991-01-01

    An analysis of measured global solar radiation in Rio de Janeiro (lat = 22{degree} 55{prime}S, long = 43{degree} 12{prime} W, sea level) is presented in the form of hourly means, decadic means, monthly means and percentage frequency distribution. The experimental data corresponds to the period from June 1979 to August 1983. The results are compared with prior predicted values found in the literature. The yearly averaged daily total global solar radiation was 16.71 MJ/m{sup 2} and the average yearly total global solar radiation was 6,099 MJ/m{sup 2}. Furthermore, these results can be used with the f-chart method by architects and heating engineers to determine the long-term thermal performance of solar heating systems.

  19. Some Results of Joint Measurements of Aerosol Extinction of Solar Radiation on Horizontal and Slant Paths

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

    Results of Joint Measurements of Aerosol Extinction of Solar Radiation on Horizontal and Slant Paths S. M. Sakerin, D. M. Kabanov, Yu. A. Pkhalagov, and V. N. Uzhegov Institute of Atmospheric Optics Tomsk, Russia Introduction It's a well-known fact that the contribution atmospheric aerosol makes in the total extinction of radiation in calculations and models of radiation must be considered; the quantitative measure of this contribution is the aerosol optical thickness of the atmosphere. The

  20. Conditions for diffusion-limited and reaction-limited recombination in nanostructured solar cells

    SciTech Connect (OSTI)

    Ansari-Rad, Mehdi; Department of Physics, University of Shahrood, Shahrood ; Anta, Juan A.; Arzi, Ezatollah

    2014-04-07

    The performance of Dye-sensitized solar cells (DSC) and related devices made of nanostructured semiconductors relies on a good charge separation, which in turn is achieved by favoring charge transport against recombination. Although both processes occur at very different time scales, hence ensuring good charge separation, in certain cases the kinetics of transport and recombination can be connected, either in a direct or an indirect way. In this work, the connection between electron transport and recombination in nanostructured solar cells is studied both theoretically and by Monte Carlo simulation. Calculations using the Multiple-Trapping model and a realistic trap distribution for nanostructured TiO{sub 2} show that for attempt-to-jump frequencies higher than 10{sup 11}–10{sup 13} Hz, the system adopts a reaction limited (RL) regime, with a lifetime which is effectively independent from the speed of the electrons in the transport level. For frequencies lower than those, and depending on the concentration of recombination centers in the material, the system enters a diffusion-limited regime (DL), where the lifetime increases if the speed of free electrons decreases. In general, the conditions for RL or DL recombination depend critically on the time scale difference between recombination kinetics and free-electron transport. Hence, if the former is too rapid with respect to the latter, the system is in the DL regime and total thermalization of carriers is not possible. In the opposite situation, a RL regime arises. Numerical data available in the literature, and the behavior of the lifetime with respect to (1) density of recombination centers and (2) probability of recombination at a given center, suggest that a typical DSC in operation stays in the RL regime with complete thermalization, although a transition to the DL regime may occur for electrolytes or hole conductors where recombination is especially rapid or where there is a larger dispersion of energies of

  1. Towards high efficiency thin-film crystalline silicon solar cells: The roles of light trapping and non-radiative recombinations

    SciTech Connect (OSTI)

    Bozzola, A. Kowalczewski, P.; Andreani, L. C.

    2014-03-07

    Thin-film solar cells based on silicon have emerged as an alternative to standard thick wafers technology, but they are less efficient, because of incomplete absorption of sunlight, and non-radiative recombinations. In this paper, we focus on the case of crystalline silicon (c-Si) devices, and we present a full analytic electro-optical model for p-n junction solar cells with Lambertian light trapping. This model is validated against numerical solutions of the drift-diffusion equations. We use this model to investigate the interplay between light trapping, and bulk and surface recombination. Special attention is paid to surface recombination processes, which become more important in thinner devices. These effects are further amplified due to the textures required for light trapping, which lead to increased surface area. We show that c-Si solar cells with thickness of a few microns can overcome 20% efficiency and outperform bulk ones when light trapping is implemented. The optimal device thickness in presence of light trapping, bulk and surface recombination, is quantified to be in the range of 1080??m, depending on the bulk quality. These results hold, provided the effective surface recombination is kept below a critical level of the order of 100?cm/s. We discuss the possibility of meeting this requirement, in the context of state-of-the-art techniques for light trapping and surface passivation. We show that our predictions are within the capability of present day silicon technologies.

  2. An evaluation of the effect of volcanic eruption on the solar radiation at Australian and Canadian stations

    SciTech Connect (OSTI)

    Yatko, B.R.; Garrison, J.D.

    1996-11-01

    Peak (most probable) and average values of {angstrom}`s turbidity coefficient {beta} and peak (most probable) and average values of the diffuse index k{sub d} are obtained from the solar radiation data from 21 stations in Australia and 5 stations in Canada. These data exhibit clear increases in their values when the volcanic aerosols in the stratosphere increase following volcanic eruptions of sufficient magnitude. The effect of the eruptions of Fuego (1974), El Chichon (1982) and Pinatubo (1991) are seen most clearly in the data. The effect of lesser eruptions is also seen. The store of volcanic aerosols in the stratosphere shifts with the season so that scattering by volcanic aerosols in the spring half of the year is stronger than in the fall.

  3. On piecewise interpolation techniques for estimating solar radiation missing values in Kedah

    SciTech Connect (OSTI)

    Saaban, Azizan; Zainudin, Lutfi; Bakar, Mohd Nazari Abu

    2014-12-04

    This paper discusses the use of piecewise interpolation method based on cubic Ball and Bézier curves representation to estimate the missing value of solar radiation in Kedah. An hourly solar radiation dataset is collected at Alor Setar Meteorology Station that is taken from Malaysian Meteorology Deparment. The piecewise cubic Ball and Bézier functions that interpolate the data points are defined on each hourly intervals of solar radiation measurement and is obtained by prescribing first order derivatives at the starts and ends of the intervals. We compare the performance of our proposed method with existing methods using Root Mean Squared Error (RMSE) and Coefficient of Detemination (CoD) which is based on missing values simulation datasets. The results show that our method is outperformed the other previous methods.

  4. Solar wind conditions leading to efficient radiation belt electron acceleration: A superposed epoch analysis

    SciTech Connect (OSTI)

    Li, W.; Thorne, R. M.; Bortnik, J.; Baker, D. N.; Reeves, G. D.; Kanekal, S. G.; Spence, H. E.; Green, J. C.

    2015-09-07

    In this study by determining preferential solar wind conditions leading to efficient radiation belt electron acceleration is crucial for predicting radiation belt electron dynamics. Using Van Allen Probes electron observations (>1 MeV) from 2012 to 2015, we identify a number of efficient and inefficient acceleration events separately to perform a superposed epoch analysis of the corresponding solar wind parameters and geomagnetic indices. By directly comparing efficient and inefficient acceleration events, we clearly show that prolonged southward Bz, high solar wind speed, and low dynamic pressure are critical for electron acceleration to >1 MeV energies in the heart of the outer radiation belt. We also evaluate chorus wave evolution using the superposed epoch analysis for the identified efficient and inefficient acceleration events and find that chorus wave intensity is much stronger and lasts longer during efficient electron acceleration events, supporting the scenario that chorus waves play a key role in MeV electron acceleration.

  5. Validation of the National Solar Radiation Database (NSRDB) (2005-2012): Preprint

    SciTech Connect (OSTI)

    Sengupta, Manajit; Weekley, Andrew; Habte, Aron; Lopez, Anthony; Molling, Christine

    2015-09-15

    Publicly accessible, high-quality, long-term, satellite-based solar resource data is foundational and critical to solar technologies to quantify system output predictions and deploy solar energy technologies in grid-tied systems. Solar radiation models have been in development for more than three decades. For many years, the National Renewable Energy Laboratory (NREL) developed and/or updated such models through the National Solar Radiation Data Base (NSRDB). There are two widely used approaches to derive solar resource data from models: (a) an empirical approach that relates ground-based observations to satellite measurements and (b) a physics-based approach that considers the radiation received at the satellite and creates retrievals to estimate clouds and surface radiation. Although empirical methods have been traditionally used for computing surface radiation, the advent of faster computing has made operational physical models viable. The Global Solar Insolation Project (GSIP) is an operational physical model from the National Oceanic and Atmospheric Administration (NOAA) that computes global horizontal irradiance (GHI) using the visible and infrared channel measurements from the Geostationary Operational Environmental Satellites (GOES) system. GSIP uses a two-stage scheme that first retrieves cloud properties and then uses those properties in the Satellite Algorithm for Surface Radiation Budget (SASRAB) model to calculate surface radiation. NREL, the University of Wisconsin, and NOAA have recently collaborated to adapt GSIP to create a high temporal and spatial resolution data set. The product initially generates the cloud properties using the AVHRR Pathfinder Atmospheres-Extended (PATMOS-x) algorithms [3], whereas the GHI is calculated using SASRAB. Then NREL implements accurate and high-resolution input parameters such as aerosol optical depth (AOD) and precipitable water vapor (PWV) to compute direct normal irradiance (DNI) using the DISC model. The AOD and

  6. Radiation resistance of thin-film solar cells for space photovoltaic power

    SciTech Connect (OSTI)

    Woodyard, J.R.; Landis, G.A.

    1991-01-01

    Copper indium diselenide, cadmium telluride, and amorphous silicon alloy solar cells have achieved noteworthy performance and are currently being studied for space power applications. Cadmium sulfide cells had been the subject of much effort but are no longer considered for space applications. A review is presented of what is known about the radiation degradation of thin film solar cells in space. Experimental cadmium telluride and amorphous silicon alloy cells are reviewed. Damage mechanisms and radiation induced defect generation and passivation in the amorphous silicon alloy cell are discussed in detail due to the greater amount of experimental data available.

  7. Extraterrestrial Materials: The Role of Synchrotron Radiation Analyses in the Study of Our Solar System

    ScienceCinema (OSTI)

    Sutton, Stephen R. [University of Chicago, Chicago, Illinois, United States

    2010-01-08

    Sample-return missions and natural collection processes have provided us with a surprisingly extensive collection of matter from Solar System bodies other than the Earth. These collections include samples from the Moon, Mars, asteroids, interplanetary dust, and, recently, from the Sun (solar wind) and a comet. This presentation will describe some of these materials, how they were collected, and what we have learned from them. Synchrotron radiation analyses of these materials are playing an increasingly valuable role in unraveling the histories and properities of the parent Solar System bodies.

  8. Pitch-angle diffusion of electrons through growing and propagating along a magnetic field electromagnetic wave in Earth's radiation belts

    SciTech Connect (OSTI)

    Choi, C.-R. Dokgo, K.; Min, K.-W.; Woo, M.-H.; Choi, E.-J.; Hwang, J.; Park, Y.-D.; Lee, D.-Y.

    2015-06-15

    The diffusion of electrons via a linearly polarized, growing electromagnetic (EM) wave propagating along a uniform magnetic field is investigated. The diffusion of electrons that interact with the growing EM wave is investigated through the autocorrelation function of the parallel electron acceleration in several tens of electron gyration timescales, which is a relatively short time compared with the bounce time of electrons between two mirror points in Earth's radiation belts. Furthermore, the pitch-angle diffusion coefficient is derived for the resonant and non-resonant electrons, and the effect of the wave growth on the electron diffusion is discussed. The results can be applied to other problems related to local acceleration or the heating of electrons in space plasmas, such as in the radiation belts.

  9. Impact of implanted phosphorus on the diffusivity of boron and its applicability to silicon solar cells

    SciTech Connect (OSTI)

    Schrof, Julian Müller, Ralph; Benick, Jan; Hermle, Martin; Reedy, Robert C.

    2015-07-28

    Boron diffusivity reduction in extrinsically doped silicon was investigated in the context of a process combination consisting of BBr{sub 3} furnace diffusion and preceding Phosphorus ion implantation. The implantation of Phosphorus leads to a substantial blocking of Boron during the subsequent Boron diffusion. First, the influences of ion implantation induced point defects as well as the initial P doping on B diffusivity were studied independently. Here, it was found that not the defects created during ion implantation but the P doping itself results in the observed B diffusion retardation. The influence of the initial P concentration was investigated in more detail by varying the P implantation dose. A secondary ion mass spectrometry (SIMS) analysis of the BSG layer after the B diffusion revealed that the B diffusion retardation is not due to potential P content in the BSG layer but rather caused by the n-type doping of the crystalline silicon itself. Based on the observations the B diffusion retardation was classified into three groups: (i) no reduction of B diffusivity, (ii) reduced B diffusivity, and (iii) blocking of the B diffusion. The retardation of B diffusion can well be explained by the phosphorus doping level resulting in a Fermi level shift and pairing of B and P ions, both reducing the B diffusivity. Besides these main influences, there are probably additional transient phenomena responsible for the blocking of boron. Those might be an interstitial transport mechanism caused by P diffusion that reduces interstitial concentration at the surface or the silicon/BSG interface shift due to oxidation during the BBr{sub 3} diffusion process. Lifetime measurements revealed that the residual (non-blocked) B leads to an increased dark saturation current density in the P doped region. Nevertheless, electrical quality is on a high level and was further increased by reducing the B dose as well as by removing the first few nanometers of the silicon surface after

  10. A comparison of the radiation tolerance characteristics of multijunction solar cells with series and voltage-matched configurations

    SciTech Connect (OSTI)

    Gee, J.M; Curtis, H.B.

    1988-01-01

    The effect of series and voltage-matched configurations on the performance of multijunction solar cells in a radiation environment was investigated. It was found that the configuration of the multijunction solar cell can have a significant impact on its radiation tolerence characteristics.

  11. Physics-Based GOES Satellite Product for Use in NREL's National Solar Radiation Database: Preprint

    SciTech Connect (OSTI)

    Sengupta, M.; Habte, A.; Gotseff, P.; Weekley, A.; Lopez, A.; Molling, C.; Heidinger, A.

    2014-07-01

    The National Renewable Energy Laboratory (NREL), University of Wisconsin, and National Oceanic Atmospheric Administration are collaborating to investigate the integration of the Satellite Algorithm for Shortwave Radiation Budget (SASRAB) products into future versions of NREL's 4-km by 4-km gridded National Solar Radiation Database (NSRDB). This paper describes a method to select an improved clear-sky model that could replace the current SASRAB global horizontal irradiance and direct normal irradiances reported during clear-sky conditions.

  12. Controlling diffusion for a self-healing radiation tolerant nanostructured ferritic alloy

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

    Miller, Michael K.; Parish, Chad M.; Bei, Hongbin

    2014-12-18

    Diffusion plays a major role in the stability of microstructures to extreme conditions of high temperature and high doses of irradiation. In nanostructured ferritic alloys, first principle calculations indicate that the binding energy of vacancies is reduced by the presence of oxygen, titanium and yttrium atoms. Therefore, the number of free vacancies available for diffusion can be greatly reduced. The mechanical properties of these alloys, compared to traditional wrought alloys of similar composition and grain structure, is distinctly different, and the ultrafine grained alloy is distinguished by a high number density of Ti–Y–O-enriched nanoclusters and solute clusters, which drives themore » mechanical response. When a displacement cascade interacts with a nanocluster, the solute atoms are locally dispersed into the matrix by ballistic collisions, but immediately a new nanocluster reforms due to the local supersaturation of solutes and vacancies until the excess vacancies are consumed. Furthermore, the result of these processes is a structural material for advanced energy systems with a microstructure that is self-healing and tolerant to high doses of radiation and high temperatures.« less

  13. An analysis of interplanetary space radiation exposure for various solar cycles

    SciTech Connect (OSTI)

    Badhwar, G.D.; O`Neill, P.M.; Cucinotta, F.A.

    1994-05-01

    The radiation dose received by crew members in interplanetary space is influenced by the stage of the solar cycle. Using the recently developed models of the galactic cosmic radiation (GCR) environment and the energy-dependent radiation transport code, we have calculated the dose at 0 and 5 cm water depth; using a computerized anatomical man (CAM) model, we have calculated the skin, eye and blood-forming organ (BFO) doses as a function of aluminum shielding for various solar minima and maxima between 1954 and 1989. These results show that the equivalent dose is within about 15% of the mean for the various solar minima (maxima). The maximum variation between solar minimum and maximum equivalent dose is about a factor of three. We have extended these calculations for the 1967-1977 solar minimum to five practical shielding geometries: Apollo Command Module, the least and most heavily shielded locations in the U.S. space shuttle mid-deck, center of the proposed Space Station Freedom cluster and sleeping compartment of the Skylab. These calculations, using the quality factor of ICRP 60, show that the average CAM BFO equivalent dose is 0.46 Sv/year. Based on an approach that takes fragmentation into account, we estimate a calculation uncertainty of 15% if the uncertainty in the quality factor is neglected. 25 refs., 11 figs., 1 tab.

  14. Control of solar radiation in buildings: a selected bibliography. [Over 70 references on fenestration design

    SciTech Connect (OSTI)

    Harmon, R.B.

    1982-01-01

    Fenestration design synthesizes many factors, including solar radiation control, daylight illumination, direct and reflected glare, the view out of the building, services, and the structure and fabric of the building in terms of energy conservation and costs. This bibliography includes books and articles related to these aspects of fenestration design in various types of structures.

  15. Equivalent circuit analysis of radiative coupling in monolithic tandem solar cells

    SciTech Connect (OSTI)

    Lan, Dongchen E-mail: d.lan@unswalumni.com; Green, Martin A.

    2015-06-29

    As solar cell efficiency improves towards the Shockley-Queisser limit, so does the radiative efficiency of the cell. For tandem stacks of cells where energy conversion efficiency now exceeds 46%, radiative coupling between the cells is becoming increasingly important to consider in cell design, measurement, and performance prediction. We show how an equivalent circuit model can capture the complex radiative interactions between cells in such tandem stacks, allowing more insight into the impact on cell performance. The circuit's use is demonstrated by deriving results relevant to the critical step of eliminating coupling effects from measured cell spectral responses.

  16. A grey diffusion acceleration method for time-dependent radiative transfer calculations

    SciTech Connect (OSTI)

    Nowak, P.F.

    1991-07-01

    The equations of thermal radiative transfer describe the emission, absorption and transport of photons in a material. As photons travel through the material they are absorbed and re-emitted in a Planckian distribution characterized by the material temperature. As a result of these processes, the material can change resulting in a change in the Planckian emission spectrum. When the coupling between the material and radiation is strong, as occurs when the material opacity or the time step is large, standard iterative techniques converge very slowly. As a result, nested iterative algorithms have been applied to the problem. One algorithm, is to use multifrequency DSA to accelerate the convergence of the multifrequency transport iteration and a grey transport acceleration (GTA) followed by a single group DSA. Here we summarize a new method which uses a grey diffusion equation (GDA) to directly solve the multifrequency transport (S{sub N}) problem. Results of Fourier analysis for both the continuous and discretized equations are discussed and the computational efficiency of GDA is compared with the DSA and GTA nested algorithms. 5 refs., 1 fig., 1 tab.

  17. Method and apparatus for measuring solar radiation in a vegetative canopy

    DOE Patents [OSTI]

    Gutschick, Vincent P.; Barron, Michael H.; Waechter, David A.; Wolf, Michael A.

    1987-01-01

    An apparatus and method for measuring solar radiation received in a vegetative canopy. A multiplicity of sensors selectively generates electrical signals in response to impinging photosynthetically active radiation in sunlight. Each sensor is attached to a plant within the canopy and is electrically connected to a separate port in a junction box having a multiplicity of ports. Each port is connected to an operational amplifier. Each amplifier amplifies the signals generated by the sensors. Each amplifier is connected to an analog-to-digital convertor which digitizes each signal. A computer is connected to the convertors and accumulates and stores solar radiation data. A data output device such as a printer is connected to the computer and displays the data.

  18. Method and apparatus for measuring solar radiation in a vegetative canopy

    DOE Patents [OSTI]

    Gutschick, V.P.; Barron, M.H.; Waechter, D.A.; Wolf, M.A.

    1985-04-30

    An apparatus and method for measuring solar radiation received in a vegetative canopy. A multiplicity of sensors selectively generates electrical signals in response to impinging photosynthetically active radiation in sunlight. Each sensor is attached to a plant within the canopy and is electrically connected to a separate port in a junction box having a multiplicity of ports. Each port is connected to an operational amplifier. Each amplifier amplifies the signals generated by the sensors. Each amplifier is connected to an analog-to-digital convertor which digitizes each signal. A computer is connected to the convertors and accumulates and stores solar radiation data. A data output device such as a printer is connected to the computer and displays the data.

  19. NREL Solar Radiation Research Laboratory (SRRL): Baseline Measurement System (BMS); Golden, Colorado (Data)

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

    Stoffel, T.; Andreas, A.

    The SRRL was established at the Solar Energy Research Institute (now NREL) in 1981 to provide continuous measurements of the solar resources, outdoor calibrations of pyranometers and pyrheliometers, and to characterize commercially available instrumentation. The SRRL is an outdoor laboratory located on South Table Mountain, a mesa providing excellent solar access throughout the year, overlooking Denver. Beginning with the basic measurements of global horizontal irradiance, direct normal irradiance and diffuse horizontal irradiance at 5-minute intervals, the SRRL Baseline Measurement System now produces more than 130 data elements at 1-min intervals that are available from the Measurement & Instrumentation Data Center Web site. Data sources include global horizontal, direct normal, diffuse horizontal (from shadowband and tracking disk), global on tilted surfaces, reflected solar irradiance, ultraviolet, infrared (upwelling and downwelling), photometric and spectral radiometers, sky imagery, and surface meteorological conditions (temperature, relative humidity, barometric pressure, precipitation, snow cover, wind speed and direction at multiple levels). Data quality control and assessment include daily instrument maintenance (M-F) with automated data quality control based on real-time examinations of redundant instrumentation and internal consistency checks using NREL's SERI-QC methodology. Operators are notified of equipment problems by automatic e-mail messages generated by the data acquisition and processing system. Radiometers are recalibrated at least annually with reference instruments traceable to the World Radiometric Reference (WRR).

  20. NREL Solar Radiation Research Laboratory (SRRL): Baseline Measurement System (BMS); Golden, Colorado (Data)

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

    Stoffel, T.; Andreas, A.

    1981-07-15

    The SRRL was established at the Solar Energy Research Institute (now NREL) in 1981 to provide continuous measurements of the solar resources, outdoor calibrations of pyranometers and pyrheliometers, and to characterize commercially available instrumentation. The SRRL is an outdoor laboratory located on South Table Mountain, a mesa providing excellent solar access throughout the year, overlooking Denver. Beginning with the basic measurements of global horizontal irradiance, direct normal irradiance and diffuse horizontal irradiance at 5-minute intervals, the SRRL Baseline Measurement System now produces more than 130 data elements at 1-min intervals that are available from the Measurement & Instrumentation Data Center Web site. Data sources include global horizontal, direct normal, diffuse horizontal (from shadowband and tracking disk), global on tilted surfaces, reflected solar irradiance, ultraviolet, infrared (upwelling and downwelling), photometric and spectral radiometers, sky imagery, and surface meteorological conditions (temperature, relative humidity, barometric pressure, precipitation, snow cover, wind speed and direction at multiple levels). Data quality control and assessment include daily instrument maintenance (M-F) with automated data quality control based on real-time examinations of redundant instrumentation and internal consistency checks using NREL's SERI-QC methodology. Operators are notified of equipment problems by automatic e-mail messages generated by the data acquisition and processing system. Radiometers are recalibrated at least annually with reference instruments traceable to the World Radiometric Reference (WRR).

  1. A comparison of data from SOLMET/ERSATZ and the National Solar Radiation Data Base

    SciTech Connect (OSTI)

    Marion, W.; Myers, D.

    1992-11-01

    This report compares data from the new National Solar Radiation Data Base (NSRDB) with data from the earlier SOLMET/ERSATZ data base. It compares the two data bases, station-by-station, with respect to their long-term average daily values of global horizontal and direct normal solar radiation. We conclude that on an annual basis, NSRDB values for global horizontal radiation are within {plus_minus}5% of SOLMET/ERSATZ values for 60% of the stations, more than 5% greater than the SOLMET/ERSATZ values for 30% of the stations, and more than 5% less than the SOLMET/ERSATZ values for 10% of the stations. On an annual basis for direct nominal radiation, the NSRDB values are with {plus_minus}5% of the SOLMET/ERSATZ data for only 40% of the stations, more than 5% greater than the SOLMET/ERSATZ values for 45% of the stations, and more than 5% less than the SOLMET/ERSATZ values for 15% of the stations. In general, the NSRDB shows higher values of solar radiation for the eastern United States, particularly the Northeast, and lower values for some of the western states (Arizona, Colorado, Idaho, Nevada, New Mexico, Utah, and Wyoming). However, because some of the stations within a state show higher values of solar radiation while others show lower values, this generalization may be misleading when concerned with a particular station. Consequently, the appendices provide tables showing a station-by-station comparison of the NSRDB and SOLMET/ERSATZ data. In addition to comparing annual values, the tables compare the two data bases for the months of August and December. This comparison shows larger differences between the two data bases for December.

  2. Estimation of total cloud cover from solar radiation observations at Lake Rotorua, New Zealand

    SciTech Connect (OSTI)

    Luo, Liancong; Hamilton, David; Han, Boping

    2010-03-15

    The DYRESM-CAEDYM model is a valuable tool for simulating water temperature for biochemical studies in aquatic ecosystem. The model requires inputs of surface short-wave radiation and long-wave radiation or total cloud cover fraction (TC). Long-wave radiation is often not measured directly so a method to determine TC from commonly measured short-wave solar irradiance (E{sub 0}) and theoretical short-wave solar irradiance under a clear sky (E{sub c}) has broad application. A more than 17-year (15 November 1991 to 20 February 2009) hourly solar irradiance data set was used to estimate the peak solar irradiance for each ordinal date over one year, which was assumed to be representative of solar irradiance in the absence of cloud. Comparison between these daily observed values and the modelled clear-sky solar radiation over one year was in close agreement (Pearson correlation coefficient, r = 0.995 and root mean squared error, RMSE = 12.54 W m{sup -2}). The downloaded hourly cloudiness measurements from 15 November 1991 to 20 February 2009 was used to calculate the daily values for this period and then the calculated daily values over the 17 years were used to calculate the average values for each ordinal date over one year. A regression equation between (1 - E{sub 0}/E{sub c}) and TC produced a correlation coefficient value of 0.99 (p > 0.01, n = 71). The validation of this cloud cover estimation model was conducted with observed short-wave solar radiation and TC at two sites. Values of TC derived from the model at the Lake Rotorua site gave a reasonable prediction of the observed values (RMSE = 0.10, r = 0.86, p > 0.01, n = 61). The model was also tested at Queenstown (South Island of New Zealand) and it provided satisfactory results compared to the measurements (RMSE = 0.16, r = 0.67, p > 0.01, n = 61). Therefore the model's good performance and broad applicability will contribute to the DYRESM-CAEDYM accuracy of water temperature simulation when long-wave radiation

  3. Radiation-Induced Changes in Normal-Appearing White Matter in Patients With Cerebral Tumors: A Diffusion Tensor Imaging Study

    SciTech Connect (OSTI)

    Nagesh, Vijaya Tsien, Christina I.; Chenevert, Thomas L.; Ross, Brian D.; Lawrence, Theodore S.; Junick, Larry; Cao Yue

    2008-03-15

    Purpose: To quantify the radiation-induced changes in normal-appearing white matter before, during, and after radiotherapy (RT) in cerebral tumor patients. Methods and Materials: Twenty-five patients with low-grade glioma, high-grade glioma, or benign tumor treated with RT were studied using diffusion tensor magnetic resonance imaging. The biologically corrected doses ranged from 50 to 81 Gy. The temporal changes were assessed before, during, and to 45 weeks after the start of RT. The mean diffusivity of water (), fractional anisotropy of diffusion, diffusivity perpendicular ({lambda}{sub perpendicular}) and parallel ({lambda}{sub parallel}) to white matter fibers were calculated in normal-appearing genu and splenium of the corpus callosum. Results: In the genu and splenium, fractional anisotropy decreased and , {lambda}{sub parallel}, {lambda}{sub -perpendicular} increased linearly and significantly with time (p < 0.01). At 45 weeks after the start of RT, {lambda}{sub -perpendicular} had increased {approx}30% in the genu and splenium, and {lambda}{sub parallel} had increased 5% in the genu and 9% in the splenium, suggesting that demyelination is predominant. The increases in {lambda}{sub perpendicular} and {lambda}{sub parallel} were dose dependent, starting at 3 weeks and continuing to 32 weeks from the start of RT. The dose-dependent increase in {lambda}{sub perpendicular} and {lambda}{sub parallel} was not sustained after 32 weeks, indicating the transition from focal to diffuse effects. Conclusion: The acute and subacute changes in normal-appearing white matter fibers indicate radiation-induced demyelination and mild structural degradation of axonal fibers. The structural changes after RT are progressive, with early dose-dependent demyelination and subsequent diffuse dose-independent demyelination and mild axonal degradation. Diffusion tensor magnetic resonance imaging is potentially a biomarker for the assessment of radiation-induced white matter injury.

  4. One-Dimensional Reaction-Diffusion Simulation of Cu Migration in Polycrystalline CdTe Solar Cells

    SciTech Connect (OSTI)

    Guo, Da; Akis, Richard; Brinkman, Daniel; Sankin, Igor; Fang, Tian; Vasileska, Dragica; Ringhofer, Christain

    2014-06-13

    In this work, we report on developing 1D reaction-diffusion solver to understand the kinetics of p-type doping formation in CdTe absorbers and to shine some light on underlying causes of metastabilities observed in CdTe PV devices. Evolution of intrinsic and Cu-related defects in CdTe solar cell has been studied in time-space domain self-consistently with free carrier transport and Poisson equation. Resulting device performance was simulated as a function of Cu diffusion anneal time showing pronounced effect the evolution of associated acceptor and donor states can cause on device characteristics. Although 1D simulation has intrinsic limitations when applied to poly-crystalline films, the results suggest strong potential of the approach in better understanding of the performance and metastabilities of CdTe photovoltaic device.

  5. EFFECTS OF NON-ISOTROPIC SCATTERING, MAGNETIC HELICITY, AND ADIABATIC FOCUSING ON DIFFUSIVE TRANSPORT OF SOLAR ENERGETIC PARTICLES

    SciTech Connect (OSTI)

    Litvinenko, Yuri E.

    2012-06-10

    Transport of solar energetic particles in interplanetary space is analyzed. A new systematic derivation of the diffusion approximation is given, which incorporates the effects of non-isotropic scattering, magnetic helicity, and adiabatic focusing in a non-uniform large-scale magnetic field. The derivation is based on a system of stochastic differential equations, equivalent to the Fokker-Planck equation, and the new method is a generalization of the Smoluchowski approximation in the theory of the Brownian motion. Simple, physically transparent expressions for the transport coefficients are derived. Different results of earlier treatments of the problem are related to the assumptions regarding the evolving particle distribution.

  6. ARM - Measurement - Shortwave broadband diffuse downwelling irradiance

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

    diffuse downwelling irradiance ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Shortwave broadband diffuse downwelling irradiance All of the solar radiation, across the wavelength range of 0.4 and 4 {mu}m, coming directly from the sky except for solar radiation coming directly from the sun and the circumsolar irradiance within approximately three degrees of the sun. Categories Radiometric Instruments

  7. Multi-criteria analysis on how to select solar radiation hydrogen production system

    SciTech Connect (OSTI)

    Badea, G.; Naghiu, G. S. Felseghi, R.-A.; Giurca, I.; Răboacă, S.; Aşchilean, I.

    2015-12-23

    The purpose of this article is to present a method of selecting hydrogen-production systems using the electric power obtained in photovoltaic systems, and as a selecting method, we suggest the use of the Advanced Multi-Criteria Analysis based on the FRISCO formula. According to the case study on how to select the solar radiation hydrogen production system, the most convenient alternative is the alternative A4, namely the technical solution involving a hydrogen production system based on the electrolysis of water vapor obtained with concentrated solar thermal systems and electrical power obtained using concentrating photovoltaic systems.

  8. Seismological comparisons of solar models with element diffusion using the MHD, OPAL, and SIREFF equations of state

    SciTech Connect (OSTI)

    Guzik, J.A.; Swenson, F.J.

    1997-12-01

    We compare the thermodynamic and helioseismic properties of solar models evolved using three different equation of state (EOS) treatments: the Mihalas, D{umlt a}ppen & Hummer EOS tables (MHD); the latest Rogers, Swenson, & Iglesias EOS tables (OPAL), and a new analytical EOS (SIREFF) developed by Swenson {ital et al.} All of the models include diffusive settling of helium and heavier elements. The models use updated OPAL opacity tables based on the 1993 Grevesse & Noels solar element mixture, incorporating 21 elements instead of the 14 elements used for earlier tables. The properties of solar models that are evolved with the SIREFF EOS agree closely with those of models evolved using the OPAL or MHD tables. However, unlike the MHD or OPAL EOS tables, the SIREFF in-line EOS can readily account for variations in overall Z abundance and the element mixture resulting from nuclear processing and diffusive element settling. Accounting for Z abundance variations in the EOS has a small, but non-negligible, effect on model properties (e.g., pressure or squared sound speed), as much as 0.2{percent} at the solar center and in the convection zone. The OPAL and SIREFF equations of state include electron exchange, which produces models requiring a slightly higher initial helium abundance, and increases the convection zone depth compared to models using the MHD EOS. However, the updated OPAL opacities are as much as 5{percent} lower near the convection zone base, resulting in a small decrease in convection zone depth. The calculated low-degree nonadiabatic frequencies for all of the models agree with the observed frequencies to within a few microhertz (0.1{percent}). The SIREFF analytical calibrations are intended to work over a wide range of interior conditions found in stellar models of mass greater than 0.25M{sub {circle_dot}} and evolutionary states from pre-main-sequence through the asymptotic giant branch (AGB). It is significant that the SIREFF EOS produces solar models

  9. Space radiation dose analysis for solar flare of August 1989

    SciTech Connect (OSTI)

    Nealy, J.E.; Simonsen, L.C.; Sauer, H.H.; Wilson, J.W.; Townsend, L.W.

    1990-12-01

    Potential dose and dose rate levels to astronauts in deep space are predicted for the solar flare event which occurred during the week of August 13, 1989. The Geostationary Operational Environmental Satellite (GOES-7) monitored the temporal development and energy characteristics of the protons emitted during this event. From these data, differential fluence as a function of energy was obtained in order to analyze the flare using the Langley baryon transport code, BRYNTRN, which describes the interactions of incident protons in matter. Dose equivalent estimates for the skin, ocular lens, and vital organs for 0.5 to 20 g/sq cm of aluminum shielding were predicted. For relatively light shielding (less than 2 g/sq cm), the skin and ocular lens 30-day exposure limits are exceeded within several hours of flare onset. The vital organ (5 cm depth) dose equivalent is exceeded only for the thinnest shield (0.5 g/sq cm). Dose rates (rem/hr) for the skin, ocular lens, and vital organs are also computed.

  10. Solar wind conditions leading to efficient radiation belt electron acceleration: A superposed epoch analysis

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

    Li, W.; Thorne, R. M.; Bortnik, J.; Baker, D. N.; Reeves, G. D.; Kanekal, S. G.; Spence, H. E.; Green, J. C.

    2015-09-07

    In this study by determining preferential solar wind conditions leading to efficient radiation belt electron acceleration is crucial for predicting radiation belt electron dynamics. Using Van Allen Probes electron observations (>1 MeV) from 2012 to 2015, we identify a number of efficient and inefficient acceleration events separately to perform a superposed epoch analysis of the corresponding solar wind parameters and geomagnetic indices. By directly comparing efficient and inefficient acceleration events, we clearly show that prolonged southward Bz, high solar wind speed, and low dynamic pressure are critical for electron acceleration to >1 MeV energies in the heart of the outermore » radiation belt. We also evaluate chorus wave evolution using the superposed epoch analysis for the identified efficient and inefficient acceleration events and find that chorus wave intensity is much stronger and lasts longer during efficient electron acceleration events, supporting the scenario that chorus waves play a key role in MeV electron acceleration.« less

  11. Comparison of Historical Satellite-Based Estimates of Solar Radiation Resources with Recent Rotating Shadowband Radiometer Measurements: Preprint

    SciTech Connect (OSTI)

    Myers, D. R.

    2009-03-01

    The availability of rotating shadow band radiometer measurement data at several new stations provides an opportunity to compare historical satellite-based estimates of solar resources with measurements. We compare mean monthly daily total (MMDT) solar radiation data from eight years of NSRDB and 22 years of NASA hourly global horizontal and direct beam solar estimates with measured data from three stations, collected after the end of the available resource estimates.

  12. Modeling tropical Pacific sea surface temperature with satellite-derived solar radiative forcing

    SciTech Connect (OSTI)

    Seager, R.; Blumenthal, M.B.

    1994-12-01

    Two independent datasets for the solar radiation at the surface derived from satellites are compared. The data derived from the Earth Radiation Budget Experiment (ERBE) is for the net solar radiation at the surface whereas the International Satellite Cloud Climatology Project (ISCCP) data is for the downward flux only and was corrected with a space- and time-varying albedo. The ISCCP net flux is at all times higher than the ERBE flux. The difference can be divided into an offset that decreases with latitude and another component that correlates with high tropical cloud cover. With this latter exception the two datasets provide spatial patterns of solar flux that are very similar. A tropical Pacific Ocean model is forced with these two datasets and observed climatological winds. The upward heat flux is parameterized taking into account separately the longwave radiative, latent, and sensible heat fluxes. Best fit values for the uncertain parameters are found using an optimization procedure that seeks to minimize the difference between model and observed SST by varying the parameters within a reasonable range of uncertainty. The SST field the model produces with the best fit parameters is the best the model can do. If the differences between the model and data are larger than can be accounted for by remaining uncertainties in the heat flux parameterization and forcing data then the ocean model must be held to be at fault. Using this method of analysis, a fundamental model fault is identified. Inadequate treatment of mixed layer/entrainment processes in upwelling regions of the eastern tropical Pacific leads to a large and seasonally varying error in the model SST. Elsewhere the model SST is insufficiently different from observed to be able to identify model errors.

  13. Potential-induced degradation in solar cells: Electronic structure and diffusion mechanism of sodium in stacking faults of silicon

    SciTech Connect (OSTI)

    Ziebarth, Benedikt Gumbsch, Peter; Mrovec, Matous; Elssser, Christian

    2014-09-07

    Sodium decorated stacking faults (SFs) were recently identified as the primary cause of potential-induced degradation in silicon (Si) solar-cells due to local electrical short-circuiting of the p-n junctions. In the present study, we investigate these defects by first principles calculations based on density functional theory in order to elucidate their structural, thermodynamic, and electronic properties. Our calculations show that the presence of sodium (Na) atoms leads to a substantial elongation of the Si-Si bonds across the SF, and the coverage and continuity of the Na layer strongly affect the diffusion behavior of Na within the SF. An analysis of the electronic structure reveals that the presence of Na in the SF gives rise to partially occupied defect levels within the Si band gap that participate in electrical conduction along the SF.

  14. Analytical solutions of a fractional diffusion-advection equation for solar cosmic-ray transport

    SciTech Connect (OSTI)

    Litvinenko, Yuri E.; Effenberger, Frederic

    2014-12-01

    Motivated by recent applications of superdiffusive transport models to shock-accelerated particle distributions in the heliosphere, we analytically solve a one-dimensional fractional diffusion-advection equation for the particle density. We derive an exact Fourier transform solution, simplify it in a weak diffusion approximation, and compare the new solution with previously available analytical results and with a semi-numerical solution based on a Fourier series expansion. We apply the results to the problem of describing the transport of energetic particles, accelerated at a traveling heliospheric shock. Our analysis shows that significant errors may result from assuming an infinite initial distance between the shock and the observer. We argue that the shock travel time should be a parameter of a realistic superdiffusive transport model.

  15. The diffusion approximation versus the telegraph equation for modeling solar energetic particle transport with adiabatic focusing. I. Isotropic pitch-angle scattering

    SciTech Connect (OSTI)

    Effenberger, Frederic; Litvinenko, Yuri E.

    2014-03-01

    The diffusion approximation to the Fokker-Planck equation is commonly used to model the transport of solar energetic particles in interplanetary space. In this study, we present exact analytical predictions of a higher order telegraph approximation for particle transport and compare them with the corresponding predictions of the diffusion approximation and numerical solutions of the full Fokker-Planck equation. We specifically investigate the role of the adiabatic focusing effect of a spatially varying magnetic field on an evolving particle distribution. Comparison of the analytical and numerical results shows that the telegraph approximation reproduces the particle intensity profiles much more accurately than does the diffusion approximation, especially when the focusing is strong. However, the telegraph approximation appears to offer no significant advantage over the diffusion approximation for calculating the particle anisotropy. The telegraph approximation can be a useful tool for describing both diffusive and wave-like aspects of the cosmic-ray transport.

  16. Simulations of hybrid system varying solar radiation and microturbine response time

    SciTech Connect (OSTI)

    Fernández Ribaya, Yolanda Álvarez, Eduardo; Paredes Sánchez, José Pablo; Xiberta Bernat, Jorge

    2015-07-15

    Hybrid power systems, such as combinations of renewable power sources with intermittent power production and non-renewable power sources, theoretically increase the reliability and thus integration of renewable sources in the electrical system. However, a recent increase in the number of hybrid installations has sparked interest in the effects of their connection to the grid, especially in remote areas. This paper analyses a photovoltaic-gas microturbine hybrid system dimensioned to be installed in La Paz (Mexico).The research presented in this paper studies and quantifies the effects on the total electric power produced, varying both the solar radiation and the gas microturbine response time. The gas microturbine and the photovoltaic panels are modelled using Matlab/Simulink software, obtaining a platform where different tests to simulate real conditions have been executed. They consist of diverse ramps of irradiance that replicate solar radiation variations, and different microturbine response times reproduced by the time constants of a first order transfer function that models the microturbine dynamic response. The results obtained show that when radiation varies quickly it does not produce significant differences in the power guarantee or the microturbine gas consumption, to any microturbine response time. However, these two parameters are highly variable with smooth radiance variations. The maximum total power variation decreases greatly as the radiation variation gets lower. In addition, by decreasing the microturbine response time, it is possible to appreciably increase the power guarantee although the maximum power variation and gas consumption increase. Only in cases of low radiation variation is there no appreciable difference in the maximum power variation obtained by the different turbine response times.

  17. Benefit of Consolidative Radiation Therapy for Primary Bone Diffuse Large B-Cell Lymphoma

    SciTech Connect (OSTI)

    Tao, Randa; Allen, Pamela K.; Rodriguez, Alma; Shihadeh, Ferial; Pinnix, Chelsea C.; Arzu, Isadora; Reed, Valerie K.; Oki, Yasuhiro; Westin, Jason R.; Fayad, Luis E.; Medeiros, L. Jeffrey; Dabaja, Bouthaina

    2015-05-01

    Purpose: Outcomes for patients with diffuse large B-cell lymphoma (DLBCL) differ according to the site of presentation. With effective chemotherapy, the need for consolidative radiation therapy (RT) is controversial. We investigated the influence of primary bone presentation and receipt of consolidative RT on progression-free survival (PFS) and overall survival (OS) in patients with DLBCL. Methods and Materials: We identified 102 patients with primary bone DLBCL treated consecutively from 1988 through 2013 and extracted clinical, pathologic, and treatment characteristics from the medical records. Survival outcomes were calculated by the Kaplan-Meier method, with factors affecting survival determined by log-rank tests. Univariate and multivariate analyses were done with a Cox regression model. Results: The median age was 55 years (range, 16-87 years). The most common site of presentation was in the long bones. Sixty-five patients (63%) received R-CHOP–based chemotherapy, and 74 (72%) received rituximab. RT was given to 67 patients (66%), 47 with stage I to II and 20 with stage III to IV disease. The median RT dose was 44 Gy (range, 24.5-50 Gy). At a median follow-up time of 82 months, the 5-year PFS and OS rates were 80% and 82%, respectively. Receipt of RT was associated with improved 5-year PFS (88% RT vs 63% no RT, P=.0069) and OS (91% vs 68%, P=.0064). On multivariate analysis, the addition of RT significantly improved PFS (hazard ratio [HR] = 0.14, P=.014) with a trend toward an OS benefit (HR=0.30, P=.053). No significant difference in PFS or OS was found between patients treated with 30 to 35 Gy versus ≥36 Gy (P=.71 PFS and P=.31 OS). Conclusion: Patients with primary bone lymphoma treated with standard chemotherapy followed by RT can have excellent outcomes. The use of consolidative RT was associated with significant benefits in both PFS and OS.

  18. NREL: Concentrating Solar Power Research - Concentrating Solar...

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

    Concentrating Solar Power Resource Maps These direct-normal solar radiation maps-filtered by solar resource and land availability-identify the most economically suitable lands ...

  19. Diffusion Tensor Imaging of Normal-Appearing White Matter as Biomarker for Radiation-Induced Late Delayed Cognitive Decline

    SciTech Connect (OSTI)

    Chapman, Christopher H.; Nagesh, Vijaya; Sundgren, Pia C.; Buchtel, Henry; Chenevert, Thomas L.; Junck, Larry; Lawrence, Theodore S.; Tsien, Christina I.; Cao, Yue

    2012-04-01

    Purpose: To determine whether early assessment of cerebral white matter degradation can predict late delayed cognitive decline after radiotherapy (RT). Methods and Materials: Ten patients undergoing conformal fractionated brain RT participated in a prospective diffusion tensor magnetic resonance imaging study. Magnetic resonance imaging studies were acquired before RT, at 3 and 6 weeks during RT, and 10, 30, and 78 weeks after starting RT. The diffusivity variables in the parahippocampal cingulum bundle and temporal lobe white matter were computed. A quality-of-life survey and neurocognitive function tests were administered before and after RT at the magnetic resonance imaging follow-up visits. Results: In both structures, longitudinal diffusivity ({lambda}{sub Double-Vertical-Line }) decreased and perpendicular diffusivity ({lambda}{sub Up-Tack }) increased after RT, with early changes correlating to later changes (p < .05). The radiation dose correlated with an increase in cingulum {lambda}{sub Up-Tack} at 3 weeks, and patients with >50% of cingula volume receiving >12 Gy had a greater increase in {lambda}{sub Up-Tack} at 3 and 6 weeks (p < .05). The post-RT changes in verbal recall scores correlated linearly with the late changes in cingulum {lambda}{sub Double-Vertical-Line} (30 weeks, p < .02). Using receiver operating characteristic curves, early cingulum {lambda}{sub Double-Vertical-Line} changes predicted for post-RT changes in verbal recall scores (3 and 6 weeks, p < .05). The neurocognitive test scores correlated significantly with the quality-of-life survey results. Conclusions: The correlation between early diffusivity changes in the parahippocampal cingulum and the late decline in verbal recall suggests that diffusion tensor imaging might be useful as a biomarker for predicting late delayed cognitive decline.

  20. Relative Accuracy of 1-Minute and Daily Total Solar Radiation Data for 12 Global and 4 Direct Beam Solar Radiometers

    SciTech Connect (OSTI)

    Myers, D.; Wilcox, S. M.

    2009-01-01

    We evaluated the relative performance of 12 global and four direct beam solar radiometers deployed at a single site over a 12-month period. Test radiometer irradiances were compared with a reference irradiance consisting of either an absolute cavity radiometer (during calibrations) or a low uncertainty thermopile pyrheliometer (during the evaluation period) for pyrheliometers; and for pyranometers a reference global irradiance computed from the reference pyrheliometer and diffuse irradiance from a shaded pyranometer. One minute averages of 3-second data for 12 months from the test instrument measurements were compared with the computed reference data set. Combined uncertainty in the computed reference irradiance is 1.8% {+-} 0.5%. Total uncertainty in the pyranometer comparisons is {+-}2.5%. We show mean percent difference between reference global irradiance and test pyranometer 1 minute data as a function of zenith angle, and percent differences between daily totals for the reference and test irradiances as a function of day number. We offer no explicit conclusion about the performance of instrument models, as a general array of applications with a wide range of instrumentation and accuracy requirements could be addressed with any of the radiometers.

  1. Evaluation of Radiometers Deployed at the National Renewable Energy Laboratory's Solar Radiation Research Laboratory

    SciTech Connect (OSTI)

    Habte, A.; Wilcox, S.; Stoffel, T.

    2014-02-01

    This study analyzes the performance of various commercially available radiometers used for measuring global horizontal irradiances and direct normal irradiances. These include pyranometers, pyrheliometers, rotating shadowband radiometers, and a pyranometer with fixed internal shading and are all deployed at the National Renewable Energy Laboratory's Solar Radiation Research Laboratory. Data from 32 global horizontal irradiance and 19 direct normal irradiance radiometers are presented. The radiometers in this study were deployed for one year (from April 1, 2011, through March 31, 2012) and compared to measurements from radiometers with the lowest values of estimated measurement uncertainties for producing reference global horizontal irradiances and direct normal irradiances.

  2. On the Green's function of the partially diffusion-controlled reversible ABCD reaction for radiation chemistry codes

    SciTech Connect (OSTI)

    Plante, Ianik; Devroye, Luc

    2015-09-15

    Several computer codes simulating chemical reactions in particles systems are based on the Green's functions of the diffusion equation (GFDE). Indeed, many types of chemical systems have been simulated using the exact GFDE, which has also become the gold standard for validating other theoretical models. In this work, a simulation algorithm is presented to sample the interparticle distance for partially diffusion-controlled reversible ABCD reaction. This algorithm is considered exact for 2-particles systems, is faster than conventional look-up tables and uses only a few kilobytes of memory. The simulation results obtained with this method are compared with those obtained with the independent reaction times (IRT) method. This work is part of our effort in developing models to understand the role of chemical reactions in the radiation effects on cells and tissues and may eventually be included in event-based models of space radiation risks. However, as many reactions are of this type in biological systems, this algorithm might play a pivotal role in future simulation programs not only in radiation chemistry, but also in the simulation of biochemical networks in time and space as well.

  3. Multi-satellite simultaneous observations of magnetopause and atmospheric losses of radiation belt electrons during an intense solar wind dynamic pressure pulse

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

    Xiang, Zheng; Ni, Binbin; Zhou, Chen; Zou, Zhengyang; Gu, Xudong; Zhao, Zhengyu; Zhang, Xianguo; Zhang, Xiaoxin; Zhang, Shenyi; Li, Xinlin; et al

    2016-05-03

    Radiation belt electron flux dropouts are a kind of drastic variation in the Earth's magnetosphere, understanding of which is of both scientific and societal importance. We report multi-satellite simultaneous observations of magnetopause and atmospheric losses of radiation belt electrons during an event of intense solar wind dynamic pressure pulse, using electron flux data from a group of 14 satellites. Moreover, when the pulse occurred, magnetopause and atmospheric loss could take effect concurrently contributing to the electron flux dropout. Losses through the magnetopause were observed to be efficient and significant at L ≳ 5, owing to the magnetopause intrusion into Lmore » ~6 and outward radial diffusion associated with sharp negative gradient in electron phase space density. Losses to the atmosphere were directly identified from the precipitating electron flux observations, for which pitch angle scattering by plasma waves could be mainly responsible. While the convection and substorm injections strongly enhanced the energetic electron fluxes up to hundreds of keV, they could delay other than avoid the occurrence of electron flux dropout at these energies. Finally, we demonstrate that the pulse-time radiation belt electron flux dropout depends strongly on the specific interplanetary and magnetospheric conditions and that losses through the magnetopause and to the atmosphere and enhancements of substorm injection play an essential role in combination, which should be incorporated as a whole into future simulations for comprehending the nature of radiation belt electron flux dropouts.« less

  4. Relative Accuracy of 1-Minute and Daily Total Solar Radiation Data for 12 Global and 4 Direct Beam Solar Radiometers: Preprint

    SciTech Connect (OSTI)

    Myers, D. R.; Wilcox, S. M.

    2009-03-01

    This report evaluates the relative performance of 12 global and four direct beam solar radiometers deployed at a single site over a 12-month period. Test radiometer irradiances were compared with a reference irradiance consisting of either an absolute cavity radiometer (during calibrations) or a low uncertainty thermopile pyrheliometer (during the evaluation period) for pyrheliometers; and for pyranometers a reference global irradiance computed from the reference pyrheliometer and diffuse irradiance from a shaded pyranometer.

  5. VISUAL-SOLAR

    Energy Science and Technology Software Center (OSTI)

    003661IBMPC00 Visual-SOLAR: Modeling and Visualization of Solar Radiation Potential on Individual Building Rooftops

  6. Back-junction back-contact n-type silicon solar cell with diffused boron emitter locally blocked by implanted phosphorus

    SciTech Connect (OSTI)

    Mller, Ralph Schrof, Julian; Reichel, Christian; Benick, Jan; Hermle, Martin

    2014-09-08

    The highest energy conversion efficiencies in the field of silicon-based photovoltaics have been achieved with back-junction back-contact (BJBC) silicon solar cells by several companies and research groups. One of the most complex parts of this cell structure is the fabrication of the locally doped p- and n-type regions, both on the back side of the solar cell. In this work, we introduce a process sequence based on a synergistic use of ion implantation and furnace diffusion. This sequence enables the formation of all doped regions for a BJBC silicon solar cell in only three processing steps. We observed that implanted phosphorus can block the diffusion of boron atoms into the silicon substrate by nearly three orders of magnitude. Thus, locally implanted phosphorus can be used as an in-situ mask for a subsequent boron diffusion which simultaneously anneals the implanted phosphorus and forms the boron emitter. BJBC silicon solar cells produced with such an easy-to-fabricate process achieved conversion efficiencies of up to 21.7%. An open-circuit voltage of 674?mV and a fill factor of 80.6% prove that there is no significant recombination at the sharp transition between the highly doped emitter and the highly doped back surface field at the device level.

  7. Solar Energy Resource Basics | Department of Energy

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

    Renewable Energy Solar Solar Energy Resource Basics Solar Energy Resource Basics August 21, 2013 - 11:40am Addthis Solar radiation, often called the solar resource, is a ...

  8. A Multigroup diffusion solver using pseudo transient continuation for a radiation-hydrodynamic code with patch-based AMR

    SciTech Connect (OSTI)

    Shestakov, A I; Offner, S R

    2006-09-21

    We present a scheme to solve the nonlinear multigroup radiation diffusion (MGD) equations. The method is incorporated into a massively parallel, multidimensional, Eulerian radiation-hydrodynamic code with adaptive mesh refinement (AMR). The patch-based AMR algorithm refines in both space and time creating a hierarchy of levels, coarsest to finest. The physics modules are time-advanced using operator splitting. On each level, separate 'level-solve' packages advance the modules. Our multigroup level-solve adapts an implicit procedure which leads to a two-step iterative scheme that alternates between elliptic solves for each group with intra-cell group coupling. For robustness, we introduce pseudo transient continuation ({Psi}tc). We analyze the magnitude of the {Psi}tc parameter to ensure positivity of the resulting linear system, diagonal dominance and convergence of the two-step scheme. For AMR, a level defines a subdomain for refinement. For diffusive processes such as MGD, the refined level uses Dirichet boundary data at the coarse-fine interface and the data is derived from the coarse level solution. After advancing on the fine level, an additional procedure, the sync-solve (SS), is required in order to enforce conservation. The MGD SS reduces to an elliptic solve on a combined grid for a system of G equations, where G is the number of groups. We adapt the 'partial temperature' scheme for the SS; hence, we reuse the infrastructure developed for scalar equations. Results are presented. We consider a multigroup test problem with a known analytic solution. We demonstrate utility of {Psi}tc by running with increasingly larger timesteps. Lastly, we simulate the sudden release of energy Y inside an Al sphere (r = 15 cm) suspended in air at STP. For Y = 11 kT, we find that gray radiation diffusion and MGD produce similar results. However, if Y = 1 MT, the two packages yield different results. Our large Y simulation contradicts a long-standing theory and demonstrates

  9. Measurement of the solar ultraviolet radiation at ground level in Bangi, Malaysia

    SciTech Connect (OSTI)

    Aljawi, Ohoud; Gopir, Geri; Duay, Abdul Basit

    2015-04-24

    Understanding the amount of ultraviolet (UV) radiation received by human, plant, and animal organisms near the earth’s surface is important to a wide range of fields such as cancer research, agriculture and forestry. The solar ultraviolet spectral irradiance at ground level was measured using the Avantes spectrometer for the period of January to March 2014 at Bangi (2°55´N, 101°46´E, 50 m above sea level) in Malaysia. These data were used to estimate the diurnal variation of UV irradiance (300 – 400 nm). The maximum irradiance of UV radiation was 45 W m{sup −2} on horizontal surface. The maximum irradiance of UV received in the local noon time, and the minimum values of UV irradiance was received in the local morning time. It is found a bigger value of UV radiation was observed on clear sky in January. The estimation of daily flux average of UV irradiance was (921± 91) kJ m{sup −2}.

  10. Hypofractionation vs Conventional Radiation Therapy for Newly Diagnosed Diffuse Intrinsic Pontine Glioma: A Matched-Cohort Analysis

    SciTech Connect (OSTI)

    Janssens, Geert O.; Jansen, Marc H.; Nowak, Peter J.; Oldenburger, Foppe R.; Bouffet, Eric; Kamphuis-van Ulzen, Karin; Lindert, Erik J. van; Schieving, Jolanda H.; Boterberg, Tom; Kaspers, Gertjan J.; Gidding, Corrie E.; Hargrave, Darren

    2013-02-01

    Purpose: Despite conventional radiation therapy, 54 Gy in single doses of 1.8 Gy (54/1.8 Gy) over 6 weeks, most children with diffuse intrinsic pontine glioma (DIPG) will die within 1 year after diagnosis. To reduce patient burden, we investigated the role of hypofractionation radiation therapy given over 3 to 4 weeks. A 1:1 matched-cohort analysis with conventional radiation therapy was performed to assess response and survival. Methods and Materials: Twenty-seven children, aged 3 to 14, were treated according to 1 of 2 hypofractionation regimens over 3 to 4 weeks (39/3 Gy, n=16 or 44.8/2.8 Gy, n=11). All patients had symptoms for {<=}3 months, {>=}2 signs of the neurologic triad (cranial nerve deficit, ataxia, long tract signs), and characteristic features of DIPG on magnetic resonance imaging. Twenty-seven patients fulfilling the same diagnostic criteria and receiving at least 50/1.8 to 2.0 Gy were eligible for the matched-cohort analysis. Results: With hypofractionation radiation therapy, the overall survival at 6, 9, and 12 months was 74%, 44%, and 22%, respectively. Progression-free survival at 3, 6, and 9 months was 77%, 43%, and 12%, respectively. Temporary discontinuation of steroids was observed in 21 of 27 (78%) patients. No significant difference in median overall survival (9.0 vs 9.4 months; P=.84) and time to progression (5.0 vs 7.6 months; P=.24) was observed between hypofractionation vs conventional radiation therapy, respectively. Conclusions: For patients with newly diagnosed DIPG, a hypofractionation regimen, given over 3 to 4 weeks, offers equal overall survival with less treatment burden compared with a conventional regimen of 6 weeks.

  11. Evaluation of two Vaisala RS92 radiosonde solar radiative dry bias correction algorithms

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

    Dzambo, Andrew M.; Turner, David D.; Mlawer, Eli J.

    2016-04-12

    Solar heating of the relative humidity (RH) probe on Vaisala RS92 radiosondes results in a large dry bias in the upper troposphere. Two different algorithms (Miloshevich et al., 2009, MILO hereafter; and Wang et al., 2013, WANG hereafter) have been designed to account for this solar radiative dry bias (SRDB). These corrections are markedly different with MILO adding up to 40 % more moisture to the original radiosonde profile than WANG; however, the impact of the two algorithms varies with height. The accuracy of these two algorithms is evaluated using three different approaches: a comparison of precipitable water vapor (PWV), downwellingmore » radiative closure with a surface-based microwave radiometer at a high-altitude site (5.3 km m.s.l.), and upwelling radiative closure with the space-based Atmospheric Infrared Sounder (AIRS). The PWV computed from the uncorrected and corrected RH data is compared against PWV retrieved from ground-based microwave radiometers at tropical, midlatitude, and arctic sites. Although MILO generally adds more moisture to the original radiosonde profile in the upper troposphere compared to WANG, both corrections yield similar changes to the PWV, and the corrected data agree well with the ground-based retrievals. The two closure activities – done for clear-sky scenes – use the radiative transfer models MonoRTM and LBLRTM to compute radiance from the radiosonde profiles to compare against spectral observations. Both WANG- and MILO-corrected RHs are statistically better than original RH in all cases except for the driest 30 % of cases in the downwelling experiment, where both algorithms add too much water vapor to the original profile. In the upwelling experiment, the RH correction applied by the WANG vs. MILO algorithm is statistically different above 10 km for the driest 30 % of cases and above 8 km for the moistest 30 % of cases, suggesting that the MILO correction performs better than the WANG in clear-sky scenes

  12. Evaluation of two Vaisala RS92 radiosonde solar radiative dry bias correction algorithms

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

    Dzambo, A. M.; Turner, D. D.; Mlawer, E. J.

    2015-10-20

    Solar heating of the relative humidity (RH) probe on Vaisala RS92 radiosondes results in a large dry bias in the upper troposphere. Two different algorithms (Miloshevich et al., 2009, MILO hereafter; and Wang et al., 2013, WANG hereafter) have been designed to account for this solar radiative dry bias (SRDB). These corrections are markedly different with MILO adding up to 40 % more moisture to the original radiosonde profile than WANG; however, the impact of the two algorithms varies with height. The accuracy of these two algorithms is evaluated using three different approaches: a comparison of precipitable water vapor (PWV),moredownwelling radiative closure with a surface-based microwave radiometer at a high-altitude site (5.3 km MSL), and upwelling radiative closure with the space-based Atmospheric Infrared Sounder (AIRS). The PWV computed from the uncorrected and corrected RH data is compared against PWV retrieved from ground-based microwave radiometers at tropical, mid-latitude, and arctic sites. Although MILO generally adds more moisture to the original radiosonde profile in the upper troposphere compared to WANG, both corrections yield similar changes to the PWV, and the corrected data agree well with the ground-based retrievals. The two closure activities done for clear-sky scenes use the radiative transfer models MonoRTM and LBLRTM to compute radiance from the radiosonde profiles to compare against spectral observations. Both WANG- and MILO-corrected RH are statistically better than original RH in all cases except for the driest 30 % of cases in the downwelling experiment, where both algorithms add too much water vapor to the original profile. In the upwelling experiment, the RH correction applied by the WANG vs. MILO algorithm is statistically different above 10 km for the driest 30 % of cases and above 8 km for the moistest 30 % of cases, suggesting that the MILO correction performs better than the WANG in clear-sky scenes. The cause of this

  13. Evaluation of two Vaisala RS92 radiosonde solar radiative dry bias correction algorithms

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

    Dzambo, Andrew M.; Turner, David D.; Mlawer, Eli J.

    2016-04-12

    Solar heating of the relative humidity (RH) probe on Vaisala RS92 radiosondes results in a large dry bias in the upper troposphere. Two different algorithms (Miloshevich et al., 2009, MILO hereafter; and Wang et al., 2013, WANG hereafter) have been designed to account for this solar radiative dry bias (SRDB). These corrections are markedly different with MILO adding up to 40 % more moisture to the original radiosonde profile than WANG; however, the impact of the two algorithms varies with height. The accuracy of these two algorithms is evaluated using three different approaches: a comparison of precipitable water vapor (PWV),more » downwelling radiative closure with a surface-based microwave radiometer at a high-altitude site (5.3 km m.s.l.), and upwelling radiative closure with the space-based Atmospheric Infrared Sounder (AIRS). The PWV computed from the uncorrected and corrected RH data is compared against PWV retrieved from ground-based microwave radiometers at tropical, midlatitude, and arctic sites. Although MILO generally adds more moisture to the original radiosonde profile in the upper troposphere compared to WANG, both corrections yield similar changes to the PWV, and the corrected data agree well with the ground-based retrievals. The two closure activities – done for clear-sky scenes – use the radiative transfer models MonoRTM and LBLRTM to compute radiance from the radiosonde profiles to compare against spectral observations. Both WANG- and MILO-corrected RHs are statistically better than original RH in all cases except for the driest 30 % of cases in the downwelling experiment, where both algorithms add too much water vapor to the original profile. In the upwelling experiment, the RH correction applied by the WANG vs. MILO algorithm is statistically different above 10 km for the driest 30 % of cases and above 8 km for the moistest 30 % of cases, suggesting that the MILO correction performs better than the WANG in clear-sky scenes. Lastly, the

  14. Synchrotron radiation and diffusive shock acceleration - A short review and GRB perspective

    SciTech Connect (OSTI)

    Karlica, Mile

    2015-12-17

    In this talk we present the sponge” model and its possible implications on the GRB afterglow light curves. “Sponge” model describes source of GRB afterglow radiation as fragmented GRB ejecta where bubbles move through the rarefied medium. In the first part of the talk a short introduction to synchrotron radiation and Fermi acceleration was presented. In the assumption that X-ray luminosity of GRB afterglow phase comes from the kinetic energy losses of clouds in ejecta medium radiated as synchrotron radiation we solved currently very simple equation of motion to find which combination of cloud and medium regime describes the afterglow light curve the best. We proposed for the first step to watch simple combinations of expansion regimes for both bubbles and surrounding medium. The closest case to the numerical fit of GRB 150403A with time power law index k = 1.38 is the combination of constant bubbles and Sedov like expanding medium with time power law index k = 1.25. Of course the question of possible mixture of variuos regime combinations is still open within this model.

  15. User`s manual for TMY2s: Derived from the 1961--1990 National Solar Radiation Data Base

    SciTech Connect (OSTI)

    Marion, W.; Urban, K.

    1995-06-01

    This report is a user`s manual that describes typical meteorological year (TMY) data sets derived from the 1961-1990 National Solar Radiation Data Base. The TMY is a data set of hourly values of solar radiation and meteorological elements for a 1-year period. The intended use if for computer simulations of solar energy conversion systems and building systems. Section 1 of the manual provides general information about the TMYs; Section 2 lists the stations and provides station identifying information and classification; Section 3 details the contents of the TMY2 files and provides the hourly records of data values; Section 4 compares TMY2 with 30-year data sets; Appendices provide procedures used to develop TMYs and a table to convert SI data to other units.

  16. The influence of clouds and diffuse radiation on ecosystem-atmosphere CO2 and CO18O exhanges

    SciTech Connect (OSTI)

    Still, C.J.; Riley, W.J.; Biraud, S.C.; Noone, D.C.; Buenning, N.H.; Randerson, J.T.; Torn, M.S.; Welker, J.; White, J.W.C.; Vachon, R.; Farquhar, G.D.; Berry, J.A.

    2009-05-01

    This study evaluates the potential impact of clouds on ecosystem CO{sub 2} and CO{sub 2} isotope fluxes ('isofluxes') in two contrasting ecosystems (a broadleaf deciduous forest and a C{sub 4} grassland), in a region for which cloud cover, meteorological, and isotope data are available for driving the isotope-enabled land surface model, ISOLSM. Our model results indicate a large impact of clouds on ecosystem CO{sub 2} fluxes and isofluxes. Despite lower irradiance on partly cloudy and cloudy days, predicted forest canopy photosynthesis was substantially higher than on clear, sunny days, and the highest carbon uptake was achieved on the cloudiest day. This effect was driven by a large increase in light-limited shade leaf photosynthesis following an increase in the diffuse fraction of irradiance. Photosynthetic isofluxes, by contrast, were largest on partly cloudy days, as leaf water isotopic composition was only slightly depleted and photosynthesis was enhanced, as compared to adjacent clear sky days. On the cloudiest day, the forest exhibited intermediate isofluxes: although photosynthesis was highest on this day, leaf-to-atmosphere isofluxes were reduced from a feedback of transpiration on canopy relative humidity and leaf water. Photosynthesis and isofluxes were both reduced in the C{sub 4} grass canopy with increasing cloud cover and diffuse fraction as a result of near-constant light limitation of photosynthesis. These results suggest that some of the unexplained variation in global mean {delta}{sup 18}O of CO{sub 2} may be driven by large-scale changes in clouds and aerosols and their impacts on diffuse radiation, photosynthesis, and relative humidity.

  17. Solar

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

    Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas ...

  18. Solar

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

    Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water ...

  19. Solar

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

    Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & ...

  20. Solar Energy Science Projects

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

    Science Projects Curriculum: Solar Power -(thermodynamics, lightelectromagnetic, radiation, energy transformation, conductionconvection, seasons, trigonometry) Grade Level: ...

  1. SOLAR RADIATION PRESSURE AND LOCAL INTERSTELLAR MEDIUM FLOW PARAMETERS FROM INTERSTELLAR BOUNDARY EXPLORER LOW ENERGY HYDROGEN MEASUREMENTS

    SciTech Connect (OSTI)

    Schwadron, N. A.; Moebius, E.; Kucharek, H.; Lee, M. A.; French, J.; Saul, L.; Wurz, P.; Bzowski, M.; Fuselier, S. A.; Livadiotis, G.; McComas, D. J.; Frisch, P.; Gruntman, M.; Mueller, H. R.

    2013-10-01

    Neutral hydrogen atoms that travel into the heliosphere from the local interstellar medium (LISM) experience strong effects due to charge exchange and radiation pressure from resonant absorption and re-emission of Ly?. The radiation pressure roughly compensates for the solar gravity. As a result, interstellar hydrogen atoms move along trajectories that are quite different than those of heavier interstellar species such as helium and oxygen, which experience relatively weak radiation pressure. Charge exchange leads to the loss of primary neutrals from the LISM and the addition of new secondary neutrals from the heliosheath. IBEX observations show clear effects of radiation pressure in a large longitudinal shift in the peak of interstellar hydrogen compared with that of interstellar helium. Here, we compare results from the Lee et al. interstellar neutral model with IBEX-Lo hydrogen observations to describe the distribution of hydrogen near 1 AU and provide new estimates of the solar radiation pressure. We find over the period analyzed from 2009 to 2011 that radiation pressure divided by the gravitational force (?) has increased slightly from ? = 0.94 0.04 in 2009 to ? = 1.01 0.05 in 2011. We have also derived the speed, temperature, source longitude, and latitude of the neutral H atoms and find that these parameters are roughly consistent with those of interstellar He, particularly when considering the filtration effects that act on H in the outer heliosheath. Thus, our analysis shows that over the period from 2009 to 2011, we observe signatures of neutral H consistent with the primary distribution of atoms from the LISM and a radiation pressure that increases in the early rise of solar activity.

  2. Effects of stratospheric ozone depletion, solar UV radiation, and climate change on biogeochemical cycling: interactions and feedbacks

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

    Erickson III, David J.; Sulzberger, Barbara; Zepp, Richard G.; Austin, Amy T.

    2014-11-07

    Climate change modulates the effects of solar UV radiation on biogeochemical cycles in terrestrial and aquatic ecosystems, particularly for carbon cycling, resulting in UV-mediated positive or negative feedbacks on climate. Possible positive feedbacks discussed in this assessment include: (i) enhanced UV-induced mineralisation of above ground litter due to aridification; (ii) enhanced UV-induced mineralisation of photoreactive dissolved organic matter (DOM) in aquatic ecosystems due to changes in continental runoff and ice melting; (iii) reduced efficiency of the biological pump due to UV-induced bleaching of coloured dissolved organic matter (CDOM) in stratified aquatic ecosystems, where CDOM protects phytoplankton from the damaging solarmore » UV-B radiation. Mineralisation of organic matter results in the production and release of CO2, whereas the biological pump is the main biological process for CO2 removal by aquatic ecosystems. This research also assesses the interactive effects of solar UV radiation and climate change on the biogeochemical cycling of aerosols and trace gases other than CO2, as well as of chemical and biological contaminants. Lastly,, interacting effects of solar UV radiation and climate change on biogeochemical cycles are particularly pronounced at terrestrial-aquatic interfaces.« less

  3. More Frequent Cloud-Free Sky and Less Surface Solar Radiation in China from 1955 to 2000

    SciTech Connect (OSTI)

    Qian, Yun; Kaiser, Dale P.; Leung, Lai R.; Xu, Ming

    2006-01-11

    Newly available data from extended weather stations and time period reveal that much of China has experienced statistically significant decreases in total cloud cover and low cloud cover over roughly the last half of the Twentieth century. This conclusion is supported by our recent analysis of the more reliably observed frequency of cloud-free sky and overcast sky. The total cloud cover and low cloud cover have decreased 0.88% and 0.33% per decade, respectively, and cloud-free days have increased 0.60% and overcast days decreased 0.78% per decade in China from 1954-2001. Meanwhile, both solar radiation and pan evaporation have decreased in most parts of China, with solar radiation decreasing 3.1 W/m2 and pan evaporation decreasing 39 mm per decade. Combined with other evidences documented in previous studies, we conjectured that increased air pollution may have produced a fog-like haze that reflected/absorbed radiation from the sun and resulted in less solar radiation reaching the surface, despite concurrent upward trends in cloud-free skies over China.

  4. Non-diffusive resonant acceleration of electrons in the radiation belts

    SciTech Connect (OSTI)

    Artemyev, A. V.; Krasnoselskikh, V. V.; Agapitov, O. V.; Rolland, G.

    2012-12-15

    We describe a mechanism of resonant electron acceleration by oblique high-amplitude whistler waves under conditions typical for the Earth radiation belts. We use statistics of spacecraft observations of whistlers in the Earth radiation belts to obtain the dependence of the angle {theta} between the wave-normal and the background magnetic field on magnetic latitude {lambda}. According to this statistics, the angle {theta} already approaches the resonance cone at {lambda}{approx}15 Degree-Sign and remains close to it up to {lambda}{approx}30 Degree-Sign -40 Degree-Sign on the dayside. The parallel component of the electrostatic field of whistler waves often increases around {lambda}{approx}15 Degree-Sign up to one hundred of mV/m. We show that due to this increase of the electric field, the whistler waves can trap electrons into the potential well via wave particle resonant interaction corresponding to Landau resonance. Trapped electrons then move with the wave to higher latitudes where they escape from the resonance. Strong acceleration is favored by adiabatic invariance along the increasing magnetic field, which continuously transfers the parallel energy gained to perpendicular energy, allowing resonance to be reached and maintained. The concomitant increase of the wave phase velocity allows for even stronger relative acceleration at low energy <50keV. Each trapping-escape event of electrons of {approx}10keV to 100 keV results in an energy gain of up to 100 keV in the inhomogeneous magnetic field of the Earth dipole. For electrons with initial energy below 100 keV, such rapid acceleration should hasten their drop into the loss-cone and their precipitation into the atmosphere. We discuss the role of the considered mechanism in the eventual formation of a trapped distribution of relativistic electrons for initial energies larger than 100 keV and in microbursts precipitations of lower energy particles.

  5. Instrument development for atmospheric radiation measurement (ARM): Status of the Atmospheric Emitted Radiance Interferometer - extended Resolution (AERI-X), the Solar Radiance Transmission Interferometer (SORTI), and the Absolute Solar Transmission Inferometer (ASTI)

    SciTech Connect (OSTI)

    Murcray, F.; Stephen, T.; Kosters, J.

    1996-04-01

    This paper describes three instruments currently under developemnt for the Atmospheric Radiation Measurement (ARM) Program at the University of Denver: the AERI-X (Atmospheric Emitted Radiance Interferometer-Extended Resolution) and the SORTI (Solar R adiance Transmission Interferometer), and ASTI (Absolute Solar transmission Interferometer).

  6. Solar Energy Educational Material, Activities and Science Projects

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

    Solar Energy Educational Materials Solar with glasses "The sun has produced energy for billions of years. Solar energy is the solar radiation that reaches the earth. Solar energy ...

  7. solar

    National Nuclear Security Administration (NNSA)

    2%2A en Solar power purchase for DOE laboratories http:nnsa.energy.govmediaroompressreleasessolarpower

  8. Solar Rights

    Broader source: Energy.gov [DOE]

    Cities and counties in North Carolina generally may not adopt ordinances prohibiting the installation of "a solar collector that gathers solar radiation as a substitute for traditional energy for...

  9. Atomistic modeling of intrinsic and radiation-enhanced fission gas (Xe) diffusion in UO2 +/- x: Implications for nuclear fuel performance modeling

    SciTech Connect (OSTI)

    Giovanni Pastore; Michael R. Tonks; Derek R. Gaston; Richard L. Williamson; David Andrs; Richard Martineau

    2014-03-01

    Based on density functional theory (DFT) and empirical potential calculations, the diffusivity of fission gas atoms (Xe) in UO2 nuclear fuel has been calculated for a range of non-stoichiometry (i.e. UO2x), under both out-of-pile (no irradiation) and in-pile (irradiation) conditions. This was achieved by first deriving expressions for the activation energy that account for the type of trap site that the fission gas atoms occupy, which includes the corresponding type of mobile cluster, the charge state of these defects and the chemistry acting as boundary condition. In the next step DFT calculations were used to estimate migration barriers and internal energy contributions to the thermodynamic properties and calculations based on empirical potentials were used to estimate defect formation and migration entropies (i.e. pre-exponentials). The diffusivities calculated for out-of-pile conditions as function of the UO2x nonstoichiometrywere used to validate the accuracy of the diffusion models and the DFT calculations against available experimental data. The Xe diffusivity is predicted to depend strongly on the UO2x non-stoichiometry due to a combination of changes in the preferred Xe trap site and in the concentration of uranium vacancies enabling Xe diffusion, which is consistent with experiments. After establishing the validity of the modeling approach, it was used for studying Xe diffusion under in-pile conditions, for which experimental data is very scarce. The radiation-enhanced Xe diffusivity is compared to existing empirical models. Finally, the predicted fission gas diffusion rates were implemented in the BISON fuel performance code and fission gas release from a Ris fuel rod irradiation experiment was simulated. 2014 Elsevier B.V. All rights

  10. Solar Radiation Map of the U.S. - Annual (National Renewable Energy Laboratory)

    SciTech Connect (OSTI)

    2009-01-18

    Maps that provide monthly average daily total solar resource information on grid cells of approximately 40 km by 40 km in size.

  11. Solar UV radiation exposure of seamen - Measurements, calibration and model calculations of erythemal irradiance along ship routes

    SciTech Connect (OSTI)

    Feister, Uwe; Meyer, Gabriele; Kirst, Ulrich

    2013-05-10

    Seamen working on vessels that go along tropical and subtropical routes are at risk to receive high doses of solar erythemal radiation. Due to small solar zenith angles and low ozone values, UV index and erythemal dose are much higher than at mid-and high latitudes. UV index values at tropical and subtropical Oceans can exceed UVI = 20, which is more than double of typical mid-latitude UV index values. Daily erythemal dose can exceed the 30-fold of typical midlatitude winter values. Measurements of erythemal exposure of different body parts on seamen have been performed along 4 routes of merchant vessels. The data base has been extended by two years of continuous solar irradiance measurements taken on the mast top of RV METEOR. Radiative transfer model calculations for clear sky along the ship routes have been performed that use satellite-based input for ozone and aerosols to provide maximum erythemal irradiance and dose. The whole data base is intended to be used to derive individual erythemal exposure of seamen during work-time.

  12. Study of the processes of degradation of the optical properties of mesoporous and macroporous silicon upon exposure to simulated solar radiation

    SciTech Connect (OSTI)

    Levitskii, V. S.; Lenshin, A. S. Seredin, P. V.; Terukov, E. I.

    2015-11-15

    The effect of solar radiation on the surface composition of mesoporous and macroporous silicon is studied by infrared spectroscopy, Raman spectroscopy, and photoluminescence measurements in order to analyze the possibility of using these materials as a material for solar-power engineering. The studies are conducted in the laboratory environment, with the use of a solar-radiation simulator operating under conditions close to the working conditions of standard silicon solar cells. The studies show that, in general, the materials meet the requirements of solar-power engineering, if it is possible to preclude harmful effects associated with the presence of heat-sensitive and photosensitive bonds at the nanomaterial surface by standard processing methods.

  13. Determination of the distribution of incident solar radiation in cavity receivers with approximately real parabolic dish collectors

    SciTech Connect (OSTI)

    Bammert, K.; Lange, H. ); Hegazy, A. )

    1990-11-01

    The absorption of solar heat and the attendant thermal and mechanical loadings on the tubes of cavity receivers depend predominantly on the flux distribution of the incident solar radiation. For an axially symmetric cavity receiver with a parabolic dish collector, it is simple to determine the insolation pattern on the receiver internal surfaces if the system is ideal. In such a system the surface of the dish is perfectly parabolic (no contour flaws are present), and the sun's central ray impinges on the dish surface parallel to the focal axis (no sun tracking flaws are present). These two conditions cannot be achieved in practice, and therefore the feasible parabolic dish system is referred to as a real system although, in actual fact, it is only an approximation to any actual system. The purpose of this paper is to devise calculation principles which permit analysis of a receiver designed for ideal conditions to verify its structural adequacy under the nonideal conditions to be expected in reality. Of the many possible imperfections in real collectors, two were selected which increase the loadings sustained. The first case concerns flaws in the contour of the dish surface. These locally increase the radiation concentration on the receiver inside walls and tubing. In the second case, sun-tracking errors give rise to axially asymmetric radiation distributions. In both examples, greater than design basis loadings will occur in the receiver tubing. Both kinds of flaws considered in this paper are of a purely deterministic nature.

  14. The radiated energy budget of chromospheric plasma in a major solar flare deduced from multi-wavelength observations

    SciTech Connect (OSTI)

    Milligan, Ryan O.; Mathioudakis, Mihalis; Keenan, Francis P.; Kerr, Graham S.; Hudson, Hugh S.; Fletcher, Lyndsay; Dennis, Brian R.; Allred, Joel C.; Chamberlin, Phillip C.; Ireland, Jack

    2014-10-01

    This paper presents measurements of the energy radiated by the lower solar atmosphere, at optical, UV, and EUV wavelengths, during an X-class solar flare (SOL2011-02-15T01:56) in response to an injection of energy assumed to be in the form of nonthermal electrons. Hard X-ray observations from RHESSI were used to track the evolution of the parameters of the nonthermal electron distribution to reveal the total power contained in flare accelerated electrons. By integrating over the duration of the impulsive phase, the total energy contained in the nonthermal electrons was found to be >2 × 10{sup 31} erg. The response of the lower solar atmosphere was measured in the free-bound EUV continua of H I (Lyman), He I, and He II, plus the emission lines of He II at 304 Å and H I (Lyα) at 1216 Å by SDO/EVE, the UV continua at 1600 Å and 1700 Å by SDO/AIA, and the white light continuum at 4504 Å, 5550 Å, and 6684 Å, along with the Ca II H line at 3968 Å using Hinode/SOT. The summed energy detected by these instruments amounted to ∼3 × 10{sup 30} erg; about 15% of the total nonthermal energy. The Lyα line was found to dominate the measured radiative losses. Parameters of both the driving electron distribution and the resulting chromospheric response are presented in detail to encourage the numerical modeling of flare heating for this event, to determine the depth of the solar atmosphere at which these line and continuum processes originate, and the mechanism(s) responsible for their generation.

  15. Solar spectral measurements and modeling

    SciTech Connect (OSTI)

    Bird, R.E.; Hulstrom, R.L.

    1981-01-01

    A newly developed spectroradiometer for routine measurement of the solar spectra is described. This instrument measures the solar spectrum between 300 and 2500 nm in less than 2.5 min, with 0.7-nm resolution in the visible and 10-nm resolution in the infrared. Many examples of global, direct, and diffuse spectra are illustrated for Bedford, Mass. and Golden, Colo. The effects of air mass, turbidity, and sun tracking on the spectrum are presented, and radiative transfer modeling capabilities and comparisons between models and between models and experiment are discussed.

  16. Solar Radiometric Data Quality Assessment of SIRS, SKYRAD and GNDRAD Measurements (Poster)

    SciTech Connect (OSTI)

    Habte, A.; Stoffel, T.; Reda, I.; Wilcox, S.; Kutchenreiter, M.; Gotseff, P.; Anderberg, M.

    2014-03-01

    Solar radiation is the driving force for the earth's weather and climate. Understanding the elements of this dynamic energy balance requires accurate measurements of broadband solar irradiance. Since the mid-1990's the ARM Program has deployed pyrheliometers and pyranometers for the measurement of direct normal irradiance (DNI), global horizontal irradiance (GHI), diffuse horizontal irradiance (DHI), and upwelling shortwave (US) radiation at permanent and mobile field research sites. This poster summarizes the basis for assessing the broadband solar radiation data available from the SIRS, SKYRAD, and GNDRAD measurement systems and provides examples of data inspections.

  17. Increasing the solar photovoltaic energy capture on sunny and cloudy days

    SciTech Connect (OSTI)

    Kelly, Nelson A.; Gibson, Thomas L.

    2011-01-15

    This report analyzes an extensive set of measurements of the solar irradiance made using four identical solar arrays and associated solar sensors (collectively referred to as solar collectors) with different tilt angles relative to the earth's surface, and thus the position of the sun, in order to determine an optimal tracking algorithm for capturing solar radiation. The study included a variety of ambient conditions including different seasons and both cloudy and cloud-free conditions. One set of solar collectors was always approximately pointed directly toward the sun (DTS) for a period around solar noon. These solar collectors thus captured the direct beam component of the solar radiation that predominates on sunny days. We found that on sunny days, solar collectors with a DTS configuration captured more solar energy in accordance with the well-known cosine dependence for the response of a flat-surfaced solar collector to the angle of incidence with direct beam radiation. In particular, a DTS orientation was found to capture up to twice as much solar energy as a horizontal (H) orientation in which the array is tilted toward the zenith. Another set of solar collectors always had an H orientation, and this best captured the diffuse component of the solar radiation that predominates on cloudy days. The dependence of the H/DTS ratio on the solar-collector tilt angle was in approximate agreement with the Isotropic Diffuse Model derived for heavily overcast conditions. During cloudy periods, we found that an H configuration increased the solar energy capture by nearly 40% compared to a DTS configuration during the same period, and we estimate the solar energy increase of an H configuration over a system that tracks the obscured solar disk could reach 50% over a whole heavily-overcast day. On an annual basis the increase is predicted to be much less, typically only about 1%, because the contribution of cloudy days to the total annual solar energy captured by a

  18. Contribution to energy conservation of opaque building materials exposed to solar radiation

    SciTech Connect (OSTI)

    Dilmac, S.; Akman, M.S.

    1990-12-01

    In the study, effects of opaque building materials on the heating of buildings by the passive solar energy system have been investigated. The quantity of solar energy absorbed by surfaces and its transfer indoors have been the main subjects of the research. Relevant surface properties and structures of opaque building skin materials have been determined experimentally and theoretically according to the meteorological, geographical and atmospheric characteristics of the regions. A laminar composite building element made of light and heavy materials has been suggested to obtain an efficient solution.

  19. Highly relativistic radiation belt electron acceleration, transport, and loss: Large solar storm events of March and June 2015

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

    Baker, Daniel N.; Jaynes, A. N.; Kanekal, S. G.; Foster, J. C.; Erickson, P. J.; Fennell, J. F.; Blake, J. B.; Zhao, H.; Li, X.; Elkington, S. R.; et al

    2016-07-26

    Two of the largest geomagnetic storms of the last decade were witnessed in 2015. On 17 March 2015, a coronal mass ejection-driven event occurred with a Dst (storm time ring current index) value reaching –223 nT. On 22 June 2015 another strong storm (Dst reaching –204 nT) was recorded. These two storms each produced almost total loss of radiation belt high-energy (E ≳ 1 MeV) electron fluxes. Following the dropouts of radiation belt fluxes there were complex and rather remarkable recoveries of the electrons extending up to nearly 10 MeV in kinetic energy. The energized outer zone electrons showed amore » rich variety of pitch angle features including strong “butterfly” distributions with deep minima in flux at α = 90°. However, despite strong driving of outer zone earthward radial diffusion in these storms, the previously reported “impenetrable barrier” at L ≈ 2.8 was pushed inward, but not significantly breached, and no E ≳ 2.0 MeV electrons were seen to pass through the radiation belt slot region to reach the inner Van Allen zone. Altogether, these intense storms show a wealth of novel features of acceleration, transport, and loss that are demonstrated in the present detailed analysis.« less

  20. Aluminoborosilicate glasses codoped with rare-earth elements as radiation-protective covers for solar cells

    SciTech Connect (OSTI)

    Malchukova, E. V. Abramov, A. S.; Nepomnyashchikh, A. I.; Terukov, E. I.

    2015-06-15

    The radiation hardness of aluminoborosilicate glasses codoped with rare-earth ions of Sm, Gd or Sm, Eu in various ratios is studied. The effect of codoping and β irradiation at a dose of 10{sup 9} Gr on the optical transmission and electron paramagnetic resonance spectra is examined. It is found that the introduction of Sm and Gd codopants in a 1 : 1 ratio reduces the number of radiation defects and raises the transmission of irradiated glasses in the visible spectral range.

  1. New Ideas for Seeding Your Solar Marketplace Program Pilots and...

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

    to make solar energy economical. AMERICA'S SOLAR DIFFUSION LABORATORIES The U.S. solar market is seeing tremendous growth, with cumulative installations doubling every 2.5...

  2. Solar Irradiances Measured using SPN1 Radiometers: Uncertainties and Clues for Development

    SciTech Connect (OSTI)

    Badosa, Jordi; Wood, John; Blanc, Philippe; Long, Charles N.; Vuilleumier, Laurent; Demengel, Dominique; Haeffelin, Martial

    2014-12-08

    The fast development of solar radiation and energy applications, such as photovoltaic and solar thermodynamic systems, has increased the need for solar radiation measurement and monitoring, not only for the global component but also the diffuse and direct. End users look for the best compromise between getting close to state-of-the-art measurements and keeping capital, maintenance and operating costs to a minimum. Among the existing commercial options, SPN1 is a relatively low cost solar radiometer that estimates global and diffuse solar irradiances from seven thermopile sensors under a shading mask and without moving parts. This work presents a comprehensive study of SPN1 accuracy and sources of uncertainty, which results from laboratory experiments, numerical modeling and comparison studies between measurements from this sensor and state-of-the art instruments for six diverse sites. Several clues are provided for improving the SPN1 accuracy and agreement with state-of-the-art measurements.

  3. Laboratory optical spectroscopy of the thiophenoxy radical and its profile simulation as a diffuse interstellar band based on rotational distribution by radiation and collisions

    SciTech Connect (OSTI)

    Araki, Mitsunori; Niwayama, Kei; Tsukiyama, Koichi

    2014-11-01

    The gas-phase optical absorption spectrum of the thiophenoxy radical (C{sub 6}H{sub 5}S), a diffuse interstellar band (DIB) candidate molecule, was observed in the discharge of thiophenol using a cavity ringdown spectrometer. The ground-state rotational constants of the thiophenoxy radical were theoretically calculated, and the excited-state rotational constants were determined from the observed rotational profile. The rotational profile of a near prolate molecule having C {sub 2v} symmetry was simulated on the basis of a rotational distribution model by radiation and collisions. Although the simulated profile did not agree with the observed DIBs, the upper limit of the column density for the thiophenoxy radical in the diffuse clouds toward HD 204827 was evaluated to be 2 × 10{sup 13} cm{sup –2}. The profile simulation indicates that rotational distribution by radiation and collisions is important to reproduce a rotational profile for a DIB candidate and that the near prolate C {sub 2v} molecule is a possible candidate for DIB with a band width variation dependent on the line of sight.

  4. On the relationship factor between the PV module temperature and the solar radiation on it for various BIPV configurations

    SciTech Connect (OSTI)

    Kaplanis, S. Kaplani, E.

    2014-10-06

    Temperatures of c-Si, pc-Si and a-Si PV modules making part of a roof in a building or hanging outside windows with various inclinations were measured with respect to the Intensity of the solar radiation on them under various environmental conditions. A relationship coefficient f was provided whose values are compared to those from a PV array operating in a free standing mode on a terrace. A theoretical model to predict f was elaborated. According to the analysis, the coefficient f takes higher values for PV modules embedded on a roof compared to the free standing PV array. The wind effect is much stronger for the free standing PV than for any BIPV configuration, either the PV is part of the roof, or placed upon the roof, or is placed outside a window like a shadow hanger. The f coefficient depends on various parameters such as angle of inclination, wind speed and direction, as well as solar radiation. For very low wind speeds the effect of the angle of inclination, ?, of the PV module with respect to the horizontal on PV temperature is clear. As the wind speed increases, the heat transfer from the PV module shifts from natural flow to forced flow and this effect vanishes. The coefficient f values range from almost 0.01 m{sup 2}C/W for free standing PV arrays at strong wind speeds, v{sub W}>7m/s, up to around 0.05 m{sup 2}C/W for the case of flexible PV modules which make part of the roof in a BIPV system.

  5. Impacts, Effectiveness and Regional Inequalities of the GeoMIP G1 to G4 Solar Radiation Management Scenarios

    SciTech Connect (OSTI)

    Yu, Xiaoyong; Moore, John; Cui, Xuefeng; Rinke, Annette; Ji, Duoying; Kravitz, Benjamin S.; Yoon, Jin-Ho

    2015-06-01

    We evaluate the regional effectiveness of solar radiation management (SRM) to compensate for simultaneous changes in temperature and precipitation induced by increased greenhouse gas concentrations. We analyze results from multiple earth system models under four Geoengineering Model Intercomparison Project(GeoMIP) experiments with a modified form of the Residual Climate Response approach. Under the solar dimming geoengineering experiments G1(4xCO2) and G2(increasing CO2 by 1% per year), global average temperature is successfully restored to pre-industrial level over 50 years simulations. However, these two SRM experiments also produce a robust global precipitation decrease. The stratospheric aerosol GeoMIP geoengineering experiment, G4 has significantly greater regional inequality and lower effectiveness for compensating temperature change than G1 and G2. G4 also has significantly larger regional inequality for compensating precipitation change than G1and G2. However, there is no significant difference between precipitation change compensation effectiveness of G4 and G2, though there is much larger across model variability in G4 results. G3 has significant greater regional inequality for compensating temperature change than G1 and G2, and has significant lower effectiveness than G1. The effectiveness of four SRMs to compensate for temperature change is much higher than for precipitation. The large cross-model variation in adjustment percentage of compensated SAT and precipitation change by SRM to achieve optimal compensation effectiveness shed a light on the uncertainty accumulation effect in optimizing compensation effectiveness of SRM.

  6. The effect of initial conditions on the electromagnetic radiation generation in type III solar radio bursts

    SciTech Connect (OSTI)

    Schmitz, H.; Tsiklauri, D.

    2013-06-15

    Extensive particle-in-cell simulations of fast electron beams injected in a background magnetised plasma with a decreasing density profile were carried out. These simulations were intended to further shed light on a newly proposed mechanism for the generation of electromagnetic waves in type III solar radio bursts [D. Tsiklauri, Phys. Plasmas, 18, 052903 (2011)]. The numerical simulations were carried out using different density profiles and fast electron distribution functions. It is shown that electromagnetic L and R modes are excited by the transverse current, initially imposed on the system. In the course of the simulations, no further interaction of the electron beam with the background plasma could be observed.

  7. FUNDING OPPORTUNITY ANNOUNCEMENT: SOLAR ENERGY EVOLUTION AND...

    Office of Environmental Management (EM)

    FUNDING OPPORTUNITY ANNOUNCEMENT: SOLAR ENERGY EVOLUTION AND DIFFUSION STUDIES II - STATE ENERGY STRATEGIES (SEEDSII-SES) FUNDING OPPORTUNITY ANNOUNCEMENT: SOLAR ENERGY EVOLUTION ...

  8. Norathyriol Suppresses Skin Cancers Induced by Solar Ultraviolet Radiation by Targeting ERK Kinases

    SciTech Connect (OSTI)

    Li, Jixia; Malakhova, Margarita; Mottamal, Madhusoodanan; Reddy, Kanamata; Kurinov, Igor; Carper, Andria; Langfald, Alyssa; Oi, Naomi; Kim, Myoung Ok; Zhu, Feng; Sosa, Carlos P.; Zhou, Keyuan; Bode, Ann M.; Dong, Zigang

    2012-06-27

    Ultraviolet (UV) irradiation is the leading factor in the development of skin cancer, prompting great interest in chemopreventive agents for this disease. In this study, we report the discovery of norathyriol, a plant-derived chemopreventive compound identified through an in silico virtual screening of the Chinese Medicine Library. Norathyriol is a metabolite of mangiferin found in mango, Hypericum elegans, and Tripterospermum lanceolatum and is known to have anticancer activity. Mechanistic investigations determined that norathyriol acted as an inhibitor of extracellular signal-regulated kinase (ERK)1/2 activity to attenuate UVB-induced phosphorylation in mitogen-activated protein kinases signaling cascades. We confirmed the direct and specific binding of norathyriol with ERK2 through a cocrystal structural analysis. The xanthone moiety in norathyriol acted as an adenine mimetic to anchor the compound by hydrogen bonds to the hinge region of the protein ATP-binding site on ERK2. Norathyriol inhibited in vitro cell growth in mouse skin epidermal JB6 P+ cells at the level of G{sub 2}-M phase arrest. In mouse skin tumorigenesis assays, norathyriol significantly suppressed solar UV-induced skin carcinogenesis. Further analysis indicated that norathyriol mediates its chemopreventive activity by inhibiting the ERK-dependent activity of transcriptional factors AP-1 and NF-{kappa}B during UV-induced skin carcinogenesis. Taken together, our results identify norathyriol as a safe new chemopreventive agent that is highly effective against development of UV-induced skin cancer.

  9. Evaluation of Arctic Broadband Surface Radiation Measurements

    SciTech Connect (OSTI)

    Matsui, N.; Long, Charles N.; Augustine, J. A.; Halliwell, D.; Uttal, Taneil; Longenecker, D.; Niebergale, J.; Wendell, J.; Albee, R.

    2012-02-24

    The Arctic is a challenging environment for making in-situ radiation measurements. A standard suite of radiation sensors is typically designed to measure the total, direct and diffuse components of incoming and outgoing broadband shortwave (SW) and broadband thermal infrared, or longwave (LW) radiation. Enhancements can include various sensors for measuring irradiance in various narrower bandwidths. Many solar radiation/thermal infrared flux sensors utilize protective glass domes and some are mounted on complex mechanical platforms (solar trackers) that rotate sensors and shading devices that track the sun. High quality measurements require striking a balance between locating sensors in a pristine undisturbed location free of artificial blockage (such as buildings and towers) and providing accessibility to allow operators to clean and maintain the instruments. Three significant sources of erroneous data include solar tracker malfunctions, rime/frost/snow deposition on the instruments and operational problems due to limited operator access in extreme weather conditions. In this study, a comparison is made between the global and component sum (direct [vertical component] + diffuse) shortwave measurements. The difference between these two quantities (that theoretically should be zero) is used to illustrate the magnitude and seasonality of radiation flux measurement problems. The problem of rime/frost/snow deposition is investigated in more detail for one case study utilizing both shortwave and longwave measurements. Solutions to these operational problems are proposed that utilize measurement redundancy, more sophisticated heating and ventilation strategies and a more systematic program of operational support and subsequent data quality protocols.

  10. Solar Sales Tax Exemption

    Broader source: Energy.gov [DOE]

    For both residential and non-residential systems, the exemption applies to solar-energy systems that utilize solar radiation to produce energy designed to provide heating, cooling, hot water and/or...

  11. Diffusion Bonding Characterization

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

    Diffusion Bonding Characterization - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense Waste Management Programs

  12. NREL: Concentrating Solar Power Research - Data and Resources

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

    Data and Resources For concentrating solar power technologies, NREL features the following online solar radiation resource data and solar resource maps, as well as data for ...

  13. Energy balance studies over varying ground cover of the Colorado River riparian zone below Glen Canyon Dam, Part II. Modeling of solar and net radiation

    SciTech Connect (OSTI)

    Brazel, A.J.; Brazel, S.W.; Marcus, M.G.

    1995-06-01

    A numerical radiation model was utilized to investigate the diurnal and seasonal variability of solar input at four sites along the Colorado River below Glen Canyon Dam: river miles -14.5, 43, 55, and 194. These simulations were compared to observations made during the spring growing season (April, 1994), the pre-monsoon dry season (June-July, 1994), the monsoon season (August, 1994), and winter (January 1995). At each river mile above, a main station was established for a 24-36 hour period observing radiation components. This station serves as a reference point to compare with simulations. The model requires specifications of sky horizon effects, albedo, atmospheric attentuation, and nearby terrain emissivity and reflectivity. A combination of field data, surveying information, and radiation theory provides an adequate methodology to yield close agreement between observations and simulations in the canyon environment. Solar shading by canyon topography can be responsible for as much 40% loss of potential photosynthetic radiation in summer months, even more at the equinoxes, and a near total reduction at some sites in winter.

  14. Improved photovoltaic energy output for cloudy conditions with a solar tracking system

    SciTech Connect (OSTI)

    Kelly, Nelson A.; Gibson, Thomas L.

    2009-11-15

    This work describes measurements of the solar irradiance made during cloudy periods in order to improve the amount of solar energy captured during such periods. It is well-known that 2-axis tracking, in which solar modules are pointed at the sun, improves the overall capture of solar energy by a given area of modules by 30-50% versus modules with a fixed tilt. On sunny days the direct sunshine accounts for up to 90% of the total solar energy, with the other 10% from diffuse (scattered) solar energy. However, during overcast conditions nearly all of the solar irradiance is diffuse radiation that is isotropically-distributed over the whole sky. An analysis of our data shows that during overcast conditions, tilting a solar module or sensor away from the zenith reduces the irradiance relative to a horizontal configuration, in which the sensor or module is pointed toward the zenith (horizontal module tilt), and thus receives the highest amount of this isotropically-distributed sky radiation. This observation led to an improved tracking algorithm in which a solar array would track the sun during cloud-free periods using 2-axis tracking, when the solar disk is visible, but go to a horizontal configuration when the sky becomes overcast. During cloudy periods we show that a horizontal module orientation increases the solar energy capture by nearly 50% compared to 2-axis solar tracking during the same period. Improving the harvesting of solar energy on cloudy days is important to using solar energy on a daily basis for fueling fuel-cell electric vehicles or charging extended-range electric vehicles because it improves the energy capture on the days with the lowest hydrogen generation, which in turn reduces the system size and cost. (author)

  15. Reconstruction and Prediction of Variations of Total Ozone and Associated Variations of UV-B Solar Radiation for Subarctic Regions Based of Dendrochronologic Data

    SciTech Connect (OSTI)

    Zuev, V.V.; Bondarenko, S.L.

    2005-03-18

    Variations of dendrochronologic parameters, especially annual ring density, significantly reflect the physiological tree response to systematic variations of solar UV-B radiation, taking place on monthly and longer timescales during growing season. Such variations of UV-B radiation are totally governed by variations of total ozone (TO). Thus, in any dendrochronologic signal, especially for coniferous trees, there is also a recorded response to TO variations, characterizing variations of UV-B radiation. Because a monitoring of global TO distribution is regularly performed since 1979 using TOMS satellite instrumentation, there appears a possibility to reconstruct TO behavior in the past practically at any point of dendrochronologic monitoring network. The reconstruction is performed by the method of linear regression, based on significant correlation of annual ring density of coniferous trees and TO for coordinates of denrochronologic signal. The present report considers the Subarctic latitudes, which are characterized by considerable TO variations in the second half of twentieth century.

  16. The influences of solar wind pressure and interplanetary magnetic field on global magnetic field and outer radiation belt electrons

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

    Yu, J.; Li, L. Y.; Cao, J. B.; Reeves, Geoffrey D.; Baker, D. N.; Spence, H.

    2016-07-22

    Using the Van Allen Probe in situ measured magnetic field and electron data, we examine the solar wind dynamic pressure and interplanetary magnetic field (IMF) effects on global magnetic field and outer radiation belt relativistic electrons (≥1.8 MeV). The dynamic pressure enhancements (>2 nPa) cause the dayside magnetic field increase and the nightside magnetic field reduction, whereas the large southward IMFs (Bz-IMF < –2nT) mainly lead to the decrease of the nightside magnetic field. In the dayside increased magnetic field region (magnetic local time (MLT) ~ 06:00–18:00, and L > 4), the pitch angles of relativistic electrons are mainly pancakemore » distributions with a flux peak around 90° (corresponding anisotropic index A > 0.1), and the higher-energy electrons have stronger pancake distributions (the larger A), suggesting that the compression-induced betatron accelerations enhance the dayside pancake distributions. However, in the nighttime decreased magnetic field region (MLT ~ 18:00–06:00, and L ≥ 5), the pitch angles of relativistic electrons become butterfly distributions with two flux peaks around 45° and 135° (A < 0). The spatial range of the nighttime butterfly distributions is almost independent of the relativistic electron energy, but it depends on the magnetic field day-night asymmetry and the interplanetary conditions. The dynamic pressure enhancements can make the nighttime butterfly distribution extend inward. The large southward IMFs can also lead to the azimuthal expansion of the nighttime butterfly distributions. As a result, these variations are consistent with the drift shell splitting and/or magnetopause shadowing effect.« less

  17. THE VEX RADIATION MODULE: 2D RADIATION TRANSPORT WITH MIMETIC...

    Office of Scientific and Technical Information (OSTI)

    THE VEX RADIATION MODULE: 2D RADIATION TRANSPORT WITH MIMETIC DIFFUSION FOR EXAFLAG Citation Details In-Document Search Title: THE VEX RADIATION MODULE: 2D RADIATION TRANSPORT WITH ...

  18. THE VEX RADIATION MODULE: 2D RADIATION TRANSPORT WITH MIMETIC...

    Office of Scientific and Technical Information (OSTI)

    THE VEX RADIATION MODULE: 2D RADIATION TRANSPORT WITH MIMETIC DIFFUSION FOR EXAFLAG Citation Details In-Document Search Title: THE VEX RADIATION MODULE: 2D RADIATION TRANSPORT WITH...

  19. Solar Selective Absorption Coatings - Energy Innovation Portal

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

    of solar selective absorber coatings that significantly improve the thermal conversion efficiency of solar units by reducing radiative energy losses from the absorbing elements. ...

  20. A New Solar Irradiance Reference Spectrum

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

    A New Solar Irradiance Reference Spectrum Pilewskie, Peter University of Colorado ... We describe the development of a new solar reference spectrum for radiation and climate ...

  1. NREL: Concentrating Solar Power Research - Laboratory Capabilities

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

    To research, develop, and test a variety of concentrating solar power technologies, NREL features the following laboratory capabilities: Concentrated Solar Radiation Facility Large ...

  2. H out-diffusion and device performance in n-i-p solar cells using high temperature hot wire a-Si:H i-layers

    SciTech Connect (OSTI)

    Mahan, A.H.; Reedy, R.C.; Iwaniczko, E.; Wang, Q.; Nelson, B.P.; Xu, Y.; Branz, H.M.; Crandall, R.S. Gallagher, A.C.; Guha, S.

    1999-03-01

    Hydrogen out-diffusion from the n/i interface region plays a major role in controlling the fill factor (FF) and resultant efficiency of n-i-p a-Si:H devices, with the i-layer deposited at high substrate temperatures by the hot wire technique. Modeling calculations have shown that a thin, highly defective layer at this interface, perhaps caused by significant H out-diffusion and incomplete lattice reconstruction, results in sharply lower device FFs due to the large voltage dropped across this defective layer. We have therefore employed buffer layers designed to retard this out-diffusion. We find that an increased H content, either in the n-layer or a thin intrinsic low temperature buffer layer, does not significantly retard this out-diffusion, as observed by SIMS H profiles on devices. However, if this low temperature buffer layer is thick enough, the out-diffusion is minimized, yielding nearly flat H profiles and a much improved device performance. We discuss this behavior in the context of the H chemical potentials and H diffusion coefficients in the high temperature, buffer, n-, and stainless steel substrate layers. Finally, we report a 9.8{percent} initial active area device, fabricated at 16.5 {Angstrom}/s, using the insights obtained in this study. Light soaking data are also reported. {copyright} {ital 1999 American Institute of Physics.}

  3. H Out-Diffusion and Device Performance in n-I-p Solar Cells Utilizing High Temperature Hot Wire a-Si:H I-Layers

    SciTech Connect (OSTI)

    Mahan, A. H; Reedy, R. C., Jr.; Iwaniczko, E.; Wang, Q.; Nelson, B. P.; Xu, Y.; Branz, H. M.; Crandall, R. S.; Gallagher, A. C.; Yang, J.; Guha, S.

    1998-11-18

    Hydrogen out-diffusion from the n/i interface region plays a major role in controlling the fill factor (FF) and resultant efficiency of n-i-p a-Si:H devices, with the i-layer deposited at high substrate temperatures by the hot wire technique. Modeling calculations have shown that a thin, highly defective layer at this interface, perhaps caused by significant H out-diffusion and incomplete lattice reconstruction, results in sharply lower device FFs due to the large voltage dropped across this defective layer. We have therefore employed buffer layers designed to retard this out-diffusion. We find that an increased H content, either in the n-layer or a thin intrinsic low temperature buffer layer, does not significantly retard this out-diffusion, as observed by SIMS H profiles on devices. However, if this low temperature buffer layer is thick enough, the out-diffusion is minimized, yielding nearly flat H profiles and a much improved device performance. We discuss this behavior in the context of the H chemical potentials and H diffusion coefficients in the high temperature, buffer, n-, and stainless steel substrate layers. Finally, we report a 9.8% initial active area device, fabricated at 16.5 {angstrom}/s, using the insights obtained in this study. Light soaking data are also reported.

  4. Insolation data manual: long-term monthly averages of solar radiation, temperature, degree-days and global anti K/sub T/ for 248 national weather service stations

    SciTech Connect (OSTI)

    Knapp, C L; Stoffel, T L; Whitaker, S D

    1980-10-01

    Monthly averaged data is presented which describes the availability of solar radiation at 248 National Weather Service stations. Monthly and annual average daily insolation and temperature values have been computed from a base of 24 to 25 years of data. Average daily maximum, minimum, and monthly temperatures are provided for most locations in both Celsius and Fahrenheit. Heating and cooling degree-days were computed relative to a base of 18.3/sup 0/C (65/sup 0/F). For each station, global anti K/sub T/ (cloudiness index) were calculated on a monthly and annual basis. (MHR)

  5. Effect of number of stack on the thermal escape and non-radiative and radiative recombinations of photoexcited carriers in strain-balanced InGaAs/GaAsP multiple quantum-well-inserted solar cells

    SciTech Connect (OSTI)

    Aihara, Taketo; Fukuyama, Atsuhiko; Ikari, Tetsuo; Suzuki, Hidetoshi; Fujii, Hiromasa; Nakano, Yoshiaki; Sugiyama, Masakazu

    2015-02-28

    Three non-destructive methodologies, namely, surface photovoltage (SPV), photoluminescence, and piezoelectric photothermal (PPT) spectroscopies, were adopted to detect the thermal carrier escape from quantum well (QW) and radiative and non-radiative carrier recombinations, respectively, in strain-balanced InGaAs/GaAsP multiple-quantum-well (MQW)-inserted GaAs p-i-n solar cell structure samples. Although the optical absorbance signal intensity was proportional to the number of QW stack, the signal intensities of the SPV and PPT methods decreased at high number of stack. To explain the temperature dependency of these signal intensities, we proposed a model that considers the three carrier dynamics: the thermal escape from the QW, and the non-radiative and radiative carrier recombinations within the QW. From the fitting procedures, it was estimated that the activation energies of the thermal escape ΔE{sub barr} and non-radiative recombination ΔE{sub NR} were 68 and 29 meV, respectively, for a 30-stacked MQW sample. The estimated ΔE{sub barr} value agreed well with the difference between the first electron subband and the top of the potential barrier in the conduction band. We found that ΔE{sub barr} remained constant at approximately 70 meV even with increasing QW stack number. However, the ΔE{sub NR} value monotonically increased with the increase in the number of stack. Since this implies that non-radiative recombination becomes improbable as the number of stack increases, we found that the radiative recombination probability for electrons photoexcited within the QW increased at a large number of QW stack. Additional processes of escaping and recapturing of carriers at neighboring QW were discussed. As a result, the combination of the three non-destructive methodologies provided us new insights for optimizing the MQW components to further improve the cell performance.

  6. Additional Survival Benefit of Involved-Lesion Radiation Therapy After R-CHOP Chemotherapy in Limited Stage Diffuse Large B-Cell Lymphoma

    SciTech Connect (OSTI)

    Kwon, Jeanny; Kim, Il Han; Kim, Byoung Hyuck; Kim, Tae Min; Heo, Dae Seog

    2015-05-01

    Purpose: The purpose of this study was to evaluate the role of involved-lesion radiation therapy (ILRT) after rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) chemotherapy in limited stage diffuse large B-cell lymphoma (DLBCL) by comparing outcomes of R-CHOP therapy alone with R-CHOP followed by ILRT. Methods and Materials: We identified 198 patients treated with R-CHOP (median, 6 cycles) for pathologically confirmed DLBCL of limited stage from July 2004 to December 2012. Clinical characteristics of these patients were 33% with stage I and 66.7% with stage II; 79.8% were in the low or low-intermediate risk group; 13.6% had B symptoms; 29.8% had bulky tumors (≥7 cm); and 75.3% underwent ≥6 cycles of R-CHOP therapy. RT was given to 43 patients (21.7%) using ILRT technique, which included the prechemotherapy tumor volume with a median margin of 2 cm (median RT dose: 36 Gy). Results: After a median follow-up of 40 months, 3-year progression-free survival (PFS) and overall survival (OS) were 85.8% and 88.9%, respectively. Multivariate analysis showed ≥6 cycles of R-CHOP (PFS, P=.004; OS, P=.004) and ILRT (PFS, P=.021; OS, P=.014) were favorable prognosticators of PFS and OS. A bulky tumor (P=.027) and response to R-CHOP (P=.012) were also found to be independent factors of OS. In subgroup analysis, the effect of ILRT was prominent in patients with a bulky tumor (PFS, P=.014; OS, P=.030) or an elevated level of serum lactate dehydrogenase (LDH; PFS, P=.004; OS, P=.012). Conclusions: Our results suggest that ILRT after R-CHOP therapy improves PFS and OS in patients with limited stage DLBCL, especially in those with bulky disease or an elevated serum LDH level.

  7. Solar collector roof

    SciTech Connect (OSTI)

    Marossy, G.; Mueller, W.E.

    1983-07-19

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

  8. Measurement and modeling of solar irradiance components on horizontal and tilted planes

    SciTech Connect (OSTI)

    Padovan, Andrea; Col, Davide del

    2010-12-15

    In this work new measurements of global and diffuse solar irradiance on the horizontal plane and global irradiance on planes tilted at 20 and 30 oriented due South and at 45 and 65 oriented due East are used to discuss the modeling of solar radiation. Irradiance data are collected in Padova (45.4 N, 11.9 E, 12 m above sea level), Italy. Some diffuse fraction correlations have been selected to model the hourly diffuse radiation on the horizontal plane. The comparison with the present experimental data shows that their prediction accuracy strongly depends on the sky characteristics. The hourly irradiance measurements taken on the tilted planes are compared with the estimations given by one isotropic and three anisotropic transposition models. The use of an anisotropic model, based on a physical description of the diffuse radiation, provides a much better accuracy, especially when measurements of the diffuse irradiance on the horizontal plane are not available and thus transposition models have to be applied in combination with a diffuse fraction correlation. This is particularly significant for the planes oriented away from South. (author)

  9. Solar selective absorption coatings

    DOE Patents [OSTI]

    Mahoney, Alan R.; Reed, Scott T.; Ashley, Carol S.; Martinez, F. Edward

    2004-08-31

    A new class of solar selective absorption coatings are disclosed. These coatings comprise a structured metallic overlayer such that the overlayer has a sub-micron structure designed to efficiently absorb solar radiation, while retaining low thermal emissivity for infrared thermal radiation. A sol-gel layer protects the structured metallic overlayer from mechanical, thermal, and environmental degradation. Processes for producing such solar selective absorption coatings are also disclosed.

  10. Solar selective absorption coatings

    DOE Patents [OSTI]

    Mahoney, Alan R.; Reed, Scott T.; Ashley, Carol S.; Martinez, F. Edward

    2003-10-14

    A new class of solar selective absorption coatings are disclosed. These coatings comprise a structured metallic overlayer such that the overlayer has a sub-micron structure designed to efficiently absorb solar radiation, while retaining low thermal emissivity for infrared thermal radiation. A sol-gel layer protects the structured metallic overlayer from mechanical, thermal, and environmental degradation. Processes for producing such solar selective absorption coatings are also disclosed.

  11. Hierarchical diffusion

    SciTech Connect (OSTI)

    Bachas, C.P.

    1988-02-01

    We review the solution and properties of the diffusion equation in a hierarchical or ultrametric space. 11 refs.

  12. International Solar Energy Conference

    SciTech Connect (OSTI)

    Rhatigan, J.L.; Christiansen, E.L.; Fleming, M.L.

    1991-01-01

    Presented here are results of a test program undertaken to further define the response of the solar dynamic radiator to hypervelocity impact (HVI). Tests were conducted on representative radiator panels (under ambient, nonoperating conditions) over a range of velocity. Target parameters are also varied. Data indicate that analytical penetration predictions are conservative (i.e., pessimistic) for the specific configuration of the solar dynamic radiator. Test results are used to define the solar dynamic radiator reliability with respect to HVI more rigorously than previous studies. Test data, reliability, and survivability results are presented.

  13. Planar photovoltaic solar concentrator module

    DOE Patents [OSTI]

    Chiang, C.J.

    1992-12-01

    A planar photovoltaic concentrator module for producing an electrical signal from incident solar radiation includes an electrically insulating housing having a front wall, an opposing back wall and a hollow interior. A solar cell having electrical terminals is positioned within the interior of the housing. A planar conductor is connected with a terminal of the solar cell of the same polarity. A lens forming the front wall of the housing is operable to direct solar radiation incident to the lens into the interior of the housing. A refractive optical element in contact with the solar cell and facing the lens receives the solar radiation directed into the interior of the housing by the lens and directs the solar radiation to the solar cell to cause the solar cell to generate an electrical signal. An electrically conductive planar member is positioned in the housing to rest on the housing back wall in supporting relation with the solar cell terminal of opposite polarity. The planar member is operable to dissipate heat radiated by the solar cell as the solar cell generates an electrical signal and further forms a solar cell conductor connected with the solar cell terminal to permit the electrical signal generated by the solar cell to be measured between the planar member and the conductor. 5 figs.

  14. Planar photovoltaic solar concentrator module

    DOE Patents [OSTI]

    Chiang, Clement J.

    1992-01-01

    A planar photovoltaic concentrator module for producing an electrical signal from incident solar radiation includes an electrically insulating housing having a front wall, an opposing back wall and a hollow interior. A solar cell having electrical terminals is positioned within the interior of the housing. A planar conductor is connected with a terminal of the solar cell of the same polarity. A lens forming the front wall of the housing is operable to direct solar radiation incident to the lens into the interior of the housing. A refractive optical element in contact with the solar cell and facing the lens receives the solar radiation directed into the interior of the housing by the lens and directs the solar radiation to the solar cell to cause the solar cell to generate an electrical signal. An electrically conductive planar member is positioned in the housing to rest on the housing back wall in supporting relation with the solar cell terminal of opposite polarity. The planar member is operable to dissipate heat radiated by the solar cell as the solar cell generates an electrical signal and further forms a solar cell conductor connected with the solar cell terminal to permit the electrical signal generated by the solar cell to be measured between the planar member and the conductor.

  15. Effects of Cu Diffusion from ZnTe:Cu/Ti Contacts on Carrier Lifetime of CdS/CdTe Thin Film Solar Cells: Preprint

    SciTech Connect (OSTI)

    Gessert, T. A.; Metzger, W. K.; Asher, S. E.; Young, M. R.; Johnston, S.; Dhere, R. G.; Duda, A.

    2008-05-01

    We study the performance of CdS/CdTe thin film PV devices processed with a ZnTe:Cu/Ti contact to investigate how carrier lifetime in the CdTe layer is affected by Cu diffusion from the contact.

  16. Solar Radiometric Data Quality Assessment of SIRS, SKYRAD and...

    Office of Scientific and Technical Information (OSTI)

    Sponsoring Org: USDOE Office of Science Country of Publication: United States Language: ... DIFFUSE HORIZONTAL IRRADIANCE; DIRECT NORMAL IRRADIANCE; Solar Energy - ...

  17. Fast Diffusion of Native Defects and Impurities in Perovskite...

    Office of Scientific and Technical Information (OSTI)

    in Perovskite Solar Cell Material CH 3 NH 3 PbI 3 Citation Details In-Document Search Title: Fast Diffusion of Native Defects and Impurities in Perovskite Solar Cell Material CH ...

  18. Diffusion and scattering in multifractal clouds

    SciTech Connect (OSTI)

    Lovejoy, S.; Schertzer, D.; Waston, B.

    1996-04-01

    This paper describes investigations of radiative properties of multifractal clouds using two different approaches. In the first, diffusion is considered by examining the scaling properties of one dimensional random walks on media with multifractal diffusivities. The second approach considers the scattering statistics associated with radiative transport.

  19. Solar retorting of oil shale

    DOE Patents [OSTI]

    Gregg, David W.

    1983-01-01

    An apparatus and method for retorting oil shale using solar radiation. Oil shale is introduced into a first retorting chamber having a solar focus zone. There the oil shale is exposed to solar radiation and rapidly brought to a predetermined retorting temperature. Once the shale has reached this temperature, it is removed from the solar focus zone and transferred to a second retorting chamber where it is heated. In a second chamber, the oil shale is maintained at the retorting temperature, without direct exposure to solar radiation, until the retorting is complete.

  20. Project Profile: Helios: Understanding Solar Evolution through...

    Energy Savers [EERE]

    Logo of SRI International. SRI International, under the Solar Energy Evolution and Diffusion ... development bottlenecks using large datasets of scientific publications, patents, ...

  1. Positron Emission Tomography/Computed Tomography Findings During Therapy Predict Outcome in Patients With Diffuse Large B-Cell Lymphoma Treated With Chemotherapy Alone but Not in Those Who Receive Consolidation Radiation

    SciTech Connect (OSTI)

    Dabaja, Bouthaina S.; Hess, Kenneth; Shihadeh, Ferial; Podoloff, Donald A.; Medeiros, L. Jeffrey; Mawlawi, Osama; Arzu, Isidora; Oki, Yasuhiro; Hagemeister, Fredrick B.; Fayad, Luis E.; Rodriguez, Alma

    2014-06-01

    Purpose: To assess the value of mid-therapy positron emission tomography (PET) findings for predicting survival and disease progression in patients with diffuse large B-cell lymphoma, considering type of therapy (chemotherapy with or without radiation therapy). Methods and Materials: We retrospectively evaluated 294 patients with histologically confirmed diffuse large B-cell lymphoma with respect to age, sex, disease stage, International Prognostic Index score, mid-therapy PET findings (positive or negative), and disease status after therapy and at last follow-up. Overall survival (OS) and progression-free survival (PFS) were compared according to mid-therapy PET findings. Results: Of the 294 patients, 163 (55%) were male, 144 (49%) were age >61 years, 110 (37%) had stage I or II disease, 219 (74%) had International Prognostic Index score ≤2, 216 (73%) received ≥6 cycles of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone, and 88 (30%) received consolidation radiation therapy. Five-year PFS and OS rates were associated with mid-therapy PET status: PFS was 78% for those with PET-negative (PET−) disease versus 63% for PET-positive (PET+) disease (P=.024), and OS was 82% for PET− versus 62% for PET+ (P<.002). These associations held true for patients who received chemotherapy only (PFS 71% for PET− vs 52% PET+ [P=.012], OS 78% for PET− and 51% for PET+ [P=.0055]) but not for those who received consolidation radiation therapy (PFS 84% PET− vs 81% PET+ [P=.88]; OS 90% PET− vs 81% PET+ [P=.39]). Conclusion: Mid-therapy PET can predict patient outcome, but the use of consolidation radiation therapy may negate the significance of mid-therapy findings.

  2. Solar Neutrinos

    DOE R&D Accomplishments [OSTI]

    Davis, R. Jr.; Harmer, D. S.

    1964-12-01

    The prospect of studying the solar energy generation process directly by observing the solar neutrino radiation has been discussed for many years. The main difficulty with this approach is that the sun emits predominantly low energy neutrinos, and detectors for observing low fluxes of low energy neutrinos have not been developed. However, experimental techniques have been developed for observing neutrinos, and one can foresee that in the near future these techniques will be improved sufficiently in sensitivity to observe solar neutrinos. At the present several experiments are being designed and hopefully will be operating in the next year or so. We will discuss an experiment based upon a neutrino capture reaction that is the inverse of the electron-capture radioactive decay of argon-37. The method depends upon exposing a large volume of a chlorine compound, removing the radioactive argon-37 and observing the characteristic decay in a small low-level counter.

  3. Two-dimensional numerical simulation of boron diffusion for pyramidally textured silicon

    SciTech Connect (OSTI)

    Ma, Fa-Jun Duttagupta, Shubham; Shetty, Kishan Devappa; Meng, Lei; Hoex, Bram; Peters, Ian Marius; Samudra, Ganesh S.

    2014-11-14

    Multidimensional numerical simulation of boron diffusion is of great relevance for the improvement of industrial n-type crystalline silicon wafer solar cells. However, surface passivation of boron diffused area is typically studied in one dimension on planar lifetime samples. This approach neglects the effects of the solar cell pyramidal texture on the boron doping process and resulting doping profile. In this work, we present a theoretical study using a two-dimensional surface morphology for pyramidally textured samples. The boron diffusivity and segregation coefficient between oxide and silicon in simulation are determined by reproducing measured one-dimensional boron depth profiles prepared using different boron diffusion recipes on planar samples. The established parameters are subsequently used to simulate the boron diffusion process on textured samples. The simulated junction depth is found to agree quantitatively well with electron beam induced current measurements. Finally, chemical passivation on planar and textured samples is compared in device simulation. Particularly, a two-dimensional approach is adopted for textured samples to evaluate chemical passivation. The intrinsic emitter saturation current density, which is only related to Auger and radiative recombination, is also simulated for both planar and textured samples. The differences between planar and textured samples are discussed.

  4. Solar heating panel arrangement

    SciTech Connect (OSTI)

    Chang, M.K.

    1983-07-12

    A solar heating panel arrangement and method are disclosed wherein a plurality of spherical lenses transmit and focus solar radiation onto the upper surface of a fluid passage for various relative positions of the sun. The upper surface of the passage is in heat transfer proximity to the fluid therein, causing solar radiation focused thereon to be transferred to the fluid in the form of heat. Solar radiation not directly incident on the lenses may be reflected onto them to increase the amount of solar energy available for transfer to the fluid. A supplementary insulating flow of fluid may also be provided above the passage to absorb heat passing upwardly therefrom and retain the heat within the system.

  5. Solar resources

    SciTech Connect (OSTI)

    Hulstrom, R.L.

    1989-01-01

    Following the 1973 oil embargo, the US government initiated a program to develop and use solar energy. This led to individual programs devoted to developing various solar radiation energy conversion technologies: photovoltaic and solar-thermal conversion devices. Nearly concurrently, it was recognized that understanding the available insolation resources was required to develop and deploy solar energy devices and systems. It was also recognized that the insolation information available at that time (1973) was not adequate to meet the specific needs of the solar energy community. Federal efforts were initiated and conducted to produce new and more extensive information and data. The primary federal agencies that undertook such efforts were the Department of Energy (DOE) and the National Oceanic and Atmospheric Administration (NOAA). NOAA's efforts included activities performed by the National Weather Service (NWS) and the National Climatic Data Center (NCDC). This book has two man objectives: to report some of the insolation energy data, information, and products produced by the federal efforts and to describe how they were produced. Products include data bases, models and algorithms, monitoring networks, instrumentation, and scientific techniques. The scope of products and results does not include all those produced by past federal efforts. The book's scope and subject matter are oriented to support the intent and purpose of the other volumes in this series. In some cases, other pertinent material is presented to provide a more complete coverage of a given subject. 385 refs., 149 figs., 50 tabs.

  6. A simulation of convective dynamo in the solar convective envelope: Maintenance of the solar-like differential rotation and emerging flux

    SciTech Connect (OSTI)

    Fan, Yuhong; Fang, Fang

    2014-07-01

    We report the results of a magnetohydrodynamic (MHD) simulation of a convective dynamo in a model solar convective envelope driven by the solar radiative diffusive heat flux. The convective dynamo produces a large-scale mean magnetic field that exhibits irregular cyclic behavior with oscillation time scales ranging from about 5 to 15 yr and undergoes irregular polarity reversals. The mean axisymmetric toroidal magnetic field is of opposite signs in the two hemispheres and is concentrated at the bottom of the convection zone. The presence of the magnetic fields is found to play an important role in the self-consistent maintenance of a solar-like differential rotation in the convective dynamo model. Without the magnetic fields, the convective flows drive a differential rotation with a faster rotating polar region. In the midst of magneto-convection, we found the emergence of strong super-equipartition flux bundles at the surface, exhibiting properties that are similar to emerging solar active regions.

  7. Solar collection

    SciTech Connect (OSTI)

    Cole, S.L.

    1984-08-01

    This report contains summaries and pictures of projects funded by the Appropriate Technology Small Grants Program which include the following solar technologies: solar dish; photovoltaics; passive solar building and solar hot water system; Trombe wall; hot air panel; hybrid solar heating system; solar grain dryer; solar greenhouse; solar hot water workshops; and solar workshops.

  8. Deriving daylight frequency distribution curves from solar radiation data to be used to implement energy saving policies in Palermo, Italy

    SciTech Connect (OSTI)

    Fanchiotti, A.; Cristofalo, S. di

    1999-07-01

    The paper presents proposed guidelines for developing a simplified tool to be used for assessing the compliance of proposed projects with city regulations, with reference to the daylighting aspects. First, the algorithms proposed for calculating the internal illuminance in a point, based on the assumption of perfectly diffusing glazings, are discussed. The result is a light transmission factor, which is a function of the position of the point and of the geometrical and physical characteristics of the room. Then, the daylight input data to be used for such calculations are presented. In order to provide designers with easy to handle data, this information is presented as frequency curves, showing the illuminance cumulative frequency distribution for a year relative to eight fundamental vertical orientations. There are different curves depending on the building type. These curves are obtained by considering only the data relative to hours and days consistent with the profile of use typical of that type of building.

  9. Community Shared Solar with Solarize | Department of Energy

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

    Community Shared Solar with Solarize Community Shared Solar with Solarize

  10. On the Results of Measurements of the Direct Sun Radiation Flux by Actinometer and of Maximal Polarization of Sky Brightness in the Solar Almucantar

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

    On the Path to SunShot - Community Solar On the Path to SunShot - Community Solar On the Path to SunShot - Community Solar In the On the Path to SunShot report series, the Emerging Opportunities and Challenges in Financing Solar report highlights how community solar has the ability to greatly expand solar access to the general public and which states currently have legislation to support it. Learn more about the reports in the On the Path to SunShot series and view all of their associated

  11. Diffusion bonding

    DOE Patents [OSTI]

    Anderson, Robert C.

    1976-06-22

    1. A method for joining beryllium to beryllium by diffusion bonding, comprising the steps of coating at least one surface portion of at least two beryllium pieces with nickel, positioning a coated surface portion in a contiguous relationship with an other surface portion, subjecting the contiguously disposed surface portions to an environment having an atmosphere at a pressure lower than ambient pressure, applying a force upon the beryllium pieces for causing the contiguous surface portions to abut against each other, heating the contiguous surface portions to a maximum temperature less than the melting temperature of the beryllium, substantially uniformly decreasing the applied force while increasing the temperature after attaining a temperature substantially above room temperature, and maintaining a portion of the applied force at a temperature corresponding to about maximum temperature for a duration sufficient to effect the diffusion bond between the contiguous surface portions.

  12. Solar Newsletter

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

    Sandia Labs Contributes to Solar Industry Innovation: A Partnership Story Customers & Partners, News, Partnership, Photovoltaic, Renewable Energy, Solar, Solar Newsletter Sandia ...

  13. Amorphous semiconductor solar cell

    DOE Patents [OSTI]

    Dalal, Vikram L.

    1981-01-01

    A solar cell comprising a back electrical contact, amorphous silicon semiconductor base and junction layers and a top electrical contact includes in its manufacture the step of heat treating the physical junction between the base layer and junction layer to diffuse the dopant species at the physical junction into the base layer.

  14. Solar Energy System and Cogeneration System Personal Property Tax Credit

    Broader source: Energy.gov [DOE]

    Eligible solar systems Solar energy is defined by D.C. Code § 34-1431 to mean "radiant energy, direct, diffuse, or reflected, received from the sun at wavelengths suitable for conversion into the...

  15. OSTIblog Articles in the diffusion Topic | OSTI, US Dept of Energy...

    Office of Scientific and Technical Information (OSTI)

    DOE Green Energy site, offers more information on the SunShot Initiative Additional Resources: Solar Energy Evolution and Diffusion Studies (SEEDS) Award Selections SunShot ...

  16. Solar thermoelectric generator

    DOE Patents [OSTI]

    Toberer, Eric S.; Baranowski, Lauryn L.; Warren, Emily L.

    2016-05-03

    Solar thermoelectric generators (STEGs) are solid state heat engines that generate electricity from concentrated sunlight. A novel detailed balance model for STEGs is provided and applied to both state-of-the-art and idealized materials. STEGs can produce electricity by using sunlight to heat one side of a thermoelectric generator. While concentrated sunlight can be used to achieve extremely high temperatures (and thus improved generator efficiency), the solar absorber also emits a significant amount of black body radiation. This emitted light is the dominant loss mechanism in these generators. In this invention, we propose a solution to this problem that eliminates virtually all of the emitted black body radiation. This enables solar thermoelectric generators to operate at higher efficiency and achieve said efficient with lower levels of optical concentration. The solution is suitable for both single and dual axis solar thermoelectric generators.

  17. PROCEEDINGS OF THE SOLAR 99 CONFERENCE

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

    SOLAR 99 CONFERENCE Including Proceedings of ASES Annual Conference Proceedings of 24 th National Passive Solar Conference Portland, Maine June 12 -16, 1999 Editors: R. Campbell-Howe B. Wilkins-Crowder American Solar Energy Society American Institute of Architects Committee on the Environment Printed on recycled paper HIGH-RESOLUTION MAPS OF SOLAR COLLECTOR PERFORMANCE USING A CLIMATOLOGICAL SOLAR RADIATION MODEL Raymond L. George National Renewable Energy Laboratory 1617 Cole Blvd. Golden, CO

  18. Cervical Gross Tumor Volume Dose Predicts Local Control Using Magnetic Resonance Imaging/Diffusion-Weighted Imaging—Guided High-Dose-Rate and Positron Emission Tomography/Computed Tomography—Guided Intensity Modulated Radiation Therapy

    SciTech Connect (OSTI)

    Dyk, Pawel; Jiang, Naomi; Sun, Baozhou; DeWees, Todd A.; Fowler, Kathryn J.; Narra, Vamsi; Garcia-Ramirez, Jose L.; Schwarz, Julie K.; Grigsby, Perry W.

    2014-11-15

    Purpose: Magnetic resonance imaging/diffusion weighted-imaging (MRI/DWI)-guided high-dose-rate (HDR) brachytherapy and {sup 18}F-fluorodeoxyglucose (FDG) — positron emission tomography/computed tomography (PET/CT)-guided intensity modulated radiation therapy (IMRT) for the definitive treatment of cervical cancer is a novel treatment technique. The purpose of this study was to report our analysis of dose-volume parameters predicting gross tumor volume (GTV) control. Methods and Materials: We analyzed the records of 134 patients with International Federation of Gynecology and Obstetrics stages IB1-IVB cervical cancer treated with combined MRI-guided HDR and IMRT from July 2009 to July 2011. IMRT was targeted to the metabolic tumor volume and lymph nodes by use of FDG-PET/CT simulation. The GTV for each HDR fraction was delineated by use of T2-weighted or apparent diffusion coefficient maps from diffusion-weighted sequences. The D100, D90, and Dmean delivered to the GTV from HDR and IMRT were summed to EQD2. Results: One hundred twenty-five patients received all irradiation treatment as planned, and 9 did not complete treatment. All 134 patients are included in this analysis. Treatment failure in the cervix occurred in 24 patients (18.0%). Patients with cervix failures had a lower D100, D90, and Dmean than those who did not experience failure in the cervix. The respective doses to the GTV were 41, 58, and 136 Gy for failures compared with 67, 99, and 236 Gy for those who did not experience failure (P<.001). Probit analysis estimated the minimum D100, D90, and Dmean doses required for ≥90% local control to be 69, 98, and 260 Gy (P<.001). Conclusions: Total dose delivered to the GTV from combined MRI-guided HDR and PET/CT-guided IMRT is highly correlated with local tumor control. The findings can be directly applied in the clinic for dose adaptation to maximize local control.

  19. Search for: "atmospheric radiation measurement" | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    (320) radiations (284) solar radiation (237) climate models (206) radar reflectivity (194) aerosols (188) climatic change (168) research programs (157) vertical velocity ...

  20. Solar skylight

    DOE Patents [OSTI]

    Adamson, James C.

    1984-01-01

    A reflective shutter rotates within a skylight housing in such a fashion as to control solar energy thereby providing a combination of heating, lighting, and ventilation. The skylight housing has three faces: a glazed southern face, a glazed northern face, and an open downwardly oriented face to the interior of the structure. Counter-weighted pivot arms support the shutter at either end causing the center of rotation to pass through the center of gravity. The shutter has three basic positions: In the first position, during the winter day, the shutter closes off the northern face, allowing solar energy to enter directly into the supporting structure providing heat gain and daylighting. In the second position, during the winter night, the shutter closes off the open face to the interior, providing insulation between the structure and the skylight housing. In the third position, during the non-heating season, the shutter closes off the southern face blocking unwanted heat gain but allowing diffuse northern light to penetrate for daylighting. In this last position, a means is provided for ventilating by natural convection. The apparatus can be operated either manually or by motor.

  1. Sensitivity of fenestration solar gain to source spectrum and angle of incidence

    SciTech Connect (OSTI)

    McCluney, W.R.

    1996-12-31

    The solar heat gain coefficient (SHGC) is the fraction of solar radiant flux incident on a fenestration system entering a building as heat gain. In general it depends on both the angle of incidence and the spectral distribution of the incident solar radiation. In attempts to improve energy performance and user acceptance of high-performance glazing systems, manufacturers are producing glazing systems with increasing spectral selectivity. This poses potential difficulties for calculations of solar heat gain through windows based upon the use of a single solar spectral weighting function. The sensitivity of modern high-performance glazing systems to both the angle of incidence and the shape of the incident solar spectrum is examined using a glazing performance simulation program. It is found that as the spectral selectivity of the glazing system increases, the SHGC can vary as the incident spectral distribution varies. The variations can be as great as 50% when using several different representative direct-beam spectra. These include spectra having low and high air masses and a standard spectrum having an air mass of 1.5. The variations can be even greater if clear blue diffuse skylight is considered. It is recommended that the current broad-band shading coefficient method of calculating solar gain be replaced by one that is spectral based.

  2. Spectral calculation of thermal performance of solar pond and comparison of the results with the experiments

    SciTech Connect (OSTI)

    Li, X.Y.; Kanayama, Kimio; Baba, Hiromu

    1999-07-01

    This paper deals with the method and the result of the spectroscopic calculation on the heat balance of a salt-gradient solar pond under the conditions of spectral solar radiation. Furthermore, the reflection of the rays incident upon the surface of the pond water, the refraction of the rays within the salt water layer and the diffusion of the salt in the pond water are considered. On the other hand, in order to make clear the mechanism of heat collection and heat storage of a solar pond, the authors conducted the indoor experiment and numerical analysis on a small scale model of salt-gradient solar pond with 2 m{sup 2} surface area and 1.6 m depth, under incident ray from a Xe-lamp solar simulator. According to above experimental analysis, the authors made a simulation model of thermal performance for a solar pond and calculated the heat balance in it. They found that the simulation calculations correspond well to the experimental result, so that their thermal simulation model might be correct. Furthermore, the authors also did the thermal calculation by changing the incident ray from Xe-lamp into natural ray, and found that the temperature distributions were notably different due to spectral characteristics of the incident ray. Therefore, the spectroscopic consideration for thermal performance of any solar pond is necessary to obtain a correct solution under the spectral incidence of special distributions.

  3. Influence of Extraterrestrial Radiation on Radiation Portal Monitors

    SciTech Connect (OSTI)

    Keller, Paul E.; Kouzes, Richard T.

    2009-06-01

    Cosmic radiation and solar flares can be a major source of background radiation at the Earths surface. This paper examines the relationship between extraterrestrial radiation and the detectable background in radiation portal monitors used for homeland security applications. Background radiation data from 13 radiation portal monitor facilities are examined and compared against external sources of data related to extraterrestrial radiation, including measurements at neutron monitors located at 53 cosmic-ray observatories around the Earth, four polar orbiting satellites, three geostationary satellites, ground-based geomagnetic field data from observatories around the Earth, a solar magnetic index, solar radio flux data, and sunspot activity data. Four-years (January 2003 through December 2006) of data are used in this study, which include the latter part of Solar Cycle 23 as solar activity was on the decline. The analysis shows a significant relationship between some extraterrestrial radiation and the background detected in the radiation portal monitors. A demonstrable decline is shown in the average gamma ray and neutron background at the radiation portal monitors as solar activity declined over the period of the study.

  4. Solar-Geophysical Data Number 557, January 1991. Part 2 (comprehensive reports). Data for July 1990 and miscellaneous

    SciTech Connect (OSTI)

    Coffey, H.E.

    1991-01-01

    ;Contents: Detailed index for 1990; Data for July 1990--Solar flares, Solar radio bursts at fixed frequencies, Interplanetary solar particles and plasma, Solar x-ray radiation from GOES satellite, Mass ejections from the sun, Active prominences and filaments.

  5. Solar Resource Measurements in Cocoa, Florida (FSEC) - Equipment Loaned to NREL: Cooperative Research and Development Final Report, CRADA Number CRD-08-318

    SciTech Connect (OSTI)

    Stoffel, T.; Afshin, A.

    2014-01-01

    Site-specific measurements of global and diffuse solar irradiance components, passively separated by alternate shading and unshading of a pyranometer mounted under a shading band with alternating opaque and open panels (for a site other than NREL) are needed to verify the underlying theory and mathematical techniques for developing direct, global and diffuse renewable resource data from such a system. These data are used for several research and development activities consistent with the NREL mission: Establish a national 30-year climatological database of measured solar irradiances; Support development of radiative transfer models for estimating solar irradiance from available meteorological observations; Provide solar resource information needed for technology deployment and operations. NREL will provide the supporting equipment (Shadow Bank Stand) for the specially designed shading band. FSEC will provide the calibrated pyranometer and perform data acquisition of the radiometer signal. Data acquired under this agreement will be shared with the NREL Principle Investigator for the purposes of validating techniques for estimating direct radiation from global and diffuse components measured with the ZEBRA system.

  6. Method for processing silicon solar cells

    DOE Patents [OSTI]

    Tsuo, Y. Simon; Landry, Marc D.; Pitts, John R.

    1997-01-01

    The instant invention teaches a novel method for fabricating silicon solar cells utilizing concentrated solar radiation. The solar radiation is concentrated by use of a solar furnace which is used to form a front surface junction and back-surface field in one processing step. The present invention also provides a method of making multicrystallline silicon from amorphous silicon. The invention also teaches a method of texturing the surface of a wafer by forming a porous silicon layer on the surface of a silicon substrate and a method of gettering impurities. Also contemplated by the invention are methods of surface passivation, forming novel solar cell structures, and hydrogen passivation.

  7. Method for processing silicon solar cells

    DOE Patents [OSTI]

    Tsuo, Y.S.; Landry, M.D.; Pitts, J.R.

    1997-05-06

    The instant invention teaches a novel method for fabricating silicon solar cells utilizing concentrated solar radiation. The solar radiation is concentrated by use of a solar furnace which is used to form a front surface junction and back-surface field in one processing step. The present invention also provides a method of making multicrystalline silicon from amorphous silicon. The invention also teaches a method of texturing the surface of a wafer by forming a porous silicon layer on the surface of a silicon substrate and a method of gettering impurities. Also contemplated by the invention are methods of surface passivation, forming novel solar cell structures, and hydrogen passivation. 2 figs.

  8. Solar Newsletter

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

    Stationary Power/Energy Conversion Efficiency/Solar Energy/Solar Newsletter Solar Newsletter Tara Camacho-Lopez 2016-07-11T20:14:36+00:00

  9. Solar Easements

    Broader source: Energy.gov [DOE]

    New Hampshire's "solar skyspace easement" provisions allow property owners to create solar easements in order to create and preserve a right to unobstructed access to solar energy. Easements remain...

  10. Parallel flow diffusion battery

    DOE Patents [OSTI]

    Yeh, H.C.; Cheng, Y.S.

    1984-01-01

    A parallel flow diffusion battery for determining the mass distribution of an aerosol has a plurality of diffusion cells mounted in parallel to an aerosol stream, each diffusion cell including a stack of mesh wire screens of different density.

  11. Parallel flow diffusion battery

    DOE Patents [OSTI]

    Yeh, Hsu-Chi; Cheng, Yung-Sung

    1984-08-07

    A parallel flow diffusion battery for determining the mass distribution of an aerosol has a plurality of diffusion cells mounted in parallel to an aerosol stream, each diffusion cell including a stack of mesh wire screens of different density.

  12. Electricity production using solar energy

    SciTech Connect (OSTI)

    Demirbas, M.F.

    2007-07-01

    In this study, a solar-powered development project is used to identify whether it is possible to utilize solar technologies in the electricity production sector. Electricity production from solar energy has been found to be a promising method in the future. Concentrated solar energy can be converted to chemical energy via high-temperature endothermic reactions. Coal and biomass can be pyrolyzed or gasified by using concentrated solar radiation for generating power. Conventional energy will not be enough to meet the continuously increasing need for energy in the future. In this case, renewable energy sources will become important. Solar energy is an increasing need for energy in the future. Solar energy is a very important energy source because of its advantages. Instead of a compressor system, which uses electricity, an absorption cooling system, using renewable energy and kinds of waste heat energy, may be used for cooling.

  13. CEG_Solar_Marketing_Report_August2009.pdf | Department of Energy

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

    CEG_Solar_Marketing_Report_August2009.pdf CEG_Solar_Marketing_Report_August2009.pdf CEG_Solar_Marketing_Report_August2009.pdf CEG_Solar_Marketing_Report_August2009.pdf (3.1 MB) More Documents & Publications Smart Solar Marketing Strategies: Clean Energy State Program Guide Clean Energy State Program Guide: Mainstreaming Solar Electricity Strategies for States to Build Local Markets Big Data Projects on Solar Tech Evolution and Diffusion

  14. Portable solar water heater

    SciTech Connect (OSTI)

    Borodulin, G.; Baron, R.; Shkolnik, A.

    1985-11-12

    A combined table and portable solar water heater comprises a suitcase-like rigid casing molded from a rigid plastic material which contains a pair of solar collector panels and connected in series. The panels can be exposed to solar radiation when the casing is opened. Each collector panel or is formed by a copper plate with the solar radiation absorbing surface and copper pipe coil or in heat-transferring relationship with said copper plate. The casing is provided with compartments for accessories, such as adjustable legs for supporting the casing, adjusting its angle to incident sunlight, and for converting the casing into a table; containers for feeding cold water to the solar collector and for receiving hot water from the collector; and a tripod stand for supporting the feeding container at the level above the collector and for arranging a shower set. Temperature-insulating layers of the collectors are formed by separate pieces of rigid material which can be removed from the casing and assembled into a box-shaped container which can be utilized for maintaining water heated by means of the solar water heater at an elevated temperature.

  15. Lowry Range Solar Station: Arapahoe County, Colorado (Data)

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

    Yoder, M.; Andreas, A.

    2008-05-30

    A partnership with industry and U.S. Department of Energy's National Renewable Energy Laboratory (NREL) to collect solar data to support future solar power generation in the United States. The measurement station monitors global horizontal, direct normal, and diffuse horizontal irradiance to define the amount of solar energy that hits this particular location. The solar measurement instrumentation is also accompanied by meteorological monitoring equipment to provide scientists with a complete picture of the solar power possibilities.

  16. Lowry Range Solar Station: Arapahoe County, Colorado (Data)

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

    Yoder, M.; Andreas, A.

    A partnership with industry and U.S. Department of Energy's National Renewable Energy Laboratory (NREL) to collect solar data to support future solar power generation in the United States. The measurement station monitors global horizontal, direct normal, and diffuse horizontal irradiance to define the amount of solar energy that hits this particular location. The solar measurement instrumentation is also accompanied by meteorological monitoring equipment to provide scientists with a complete picture of the solar power possibilities.

  17. Thermophotovoltaics | Solid State Solar Thermal Energy Conversion

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

    Thermophotovoltaics Solar Thermophotovoltaics (STPVs) are solar driven heat engines which extract electrical power from thermal radiation. The overall goal is to absorb and convert the broadband solar radiation spectrum into a narrowband thermal emission spectrum tuned to the spectral response of a photovoltaic cell (PV) [1]. STPVs are of significant interest as they have the potential to overcome the well-known Shockley-Queisser limit for single junction PV given sufficient spectral control.

  18. Solar panel with interconnects and masking structure, and method

    SciTech Connect (OSTI)

    Gaddy, E.M.; Dominguez, R.

    1991-04-30

    This patent describes a solar panel. It includes: solar cells having radiation absorbing surface and opposed back surfaces; conducting means for interconnecting the solar cells; a transparent superstrate upon one surface of which radiation absorbing surfaces are mounted; and means upon a surface of the transparent superstrate for masking the interconnecting means.

  19. Annual collectible energy of a two-axis tracking flat-plate solar collector

    SciTech Connect (OSTI)

    Attalage, R.A.; Reddy, T.A. )

    1992-01-01

    A correlation for annual collectible energy of a two-axis tracking flat-plate solar collector has been developed using simulated results based on typical meteorological year (TMY) data for 26 US locations. A preliminary validation of this correlation has been carried out with data from four Australian locations. With the advent of increasing interest in photovoltaic systems, there are a number of advantages of using a two-axis flat-plate collector. Since the tracking system is generally much cheaper than the collector panel, such a mode permits the incident solar radiation to be collected more efficiently. Incidence angle effects are minimized and, moreover, contrary to concentrating collectors, such a mode enables both the diffuse and beam components of solar radiation to be collected. In tropical locations where the diffuse fraction is generally high, this may be a great advantage. The objective of this study was to develop a correlation for the annual collectible energy of a two-axis tracking flat-plate collector.

  20. Light-trapping and recycling for extraordinary power conversion in ultra-thin gallium-arsenide solar cells

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

    Eyderman, Sergey; John, Sajeev

    2016-06-23

    Here, we demonstrate nearly 30% power conversion efficiency in ultra-thin (~200 nm) gallium arsenide photonic crystal solar cells by numerical solution of the coupled electromagnetic Maxwell and semiconductor drift-diffusion equations. Our architecture enables wave-interference-induced solar light trapping in the wavelength range from 300-865 nm, leading to absorption of almost 90% of incoming sunlight. Our optimized design for 200 nm equivalent bulk thickness of GaAs, is a square-lattice, slanted conical-pore photonic crystal (lattice constant 550 nm, pore diameter 600 nm, and pore depth 290 nm), passivated with AlGaAs, deposited on a silver back-reflector, with ITO upper contact and encapsulated with SiO2.more » Our model includes both radiative and non-radiative recombination of photo-generated charge carriers. When all light from radiative recombination is assumed to escape the structure, a maximum achievable photocurrent density (MAPD) of 27.6 mA/cm2 is obtained from normally incident AM 1.5 sunlight. For a surface non-radiative recombination velocity of 103 cm/s, this corresponds to a solar power conversion efficiency of 28.3%. When all light from radiative recombination is trapped and reabsorbed (complete photon recycling) the power conversion efficiency increases to 29%. If the surface recombination velocity is reduced to 10 cm/sec, photon recycling is much more effective and the power conversion efficiency reaches 30.6%.« less

  1. First Solar Manufacturing Solar Modules

    Broader source: Energy.gov [DOE]

    In this photograph, a First Solar associate handles photovoltaic materials at the company's Ohio manufacturing plant. First Solar is an industry partner with the U.S. Department of Energy Solar...

  2. Region Solar Inc Solar Inc California Renewable Energy Solar...

    Open Energy Info (EERE)

    Point Drive Fort Collins Colorado Solar Solar cell passive solar architectural glass solar grid tie inverter semiconductor flat panel display data storage http www advanced...

  3. NREL: Solar Research - Solar Newsletter

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

    Solar Newsletter Subscribe: To receive new issues by email, subscribe to the newsletter. The Solar Newsletter is a monthly electronic newsletter that provides information on NREL's ...

  4. TJ Solar Cell

    SciTech Connect (OSTI)

    Friedman, Daniel

    2009-04-17

    This talk will discuss recent developments in III-V multijunction photovoltaic technology which have led to the highest-efficiency solar cells ever demonstrated. The relationship between the materials science of III-V semiconductors and the achievement of record solar cell efficiencies will be emphasized. For instance, epitaxially-grown GAInP has been found to form a spontaneously-ordered GaP/InP (111) superlattice. This ordering affects the band gap of the material, which in turn affects the design of solar cells which incorporate GaInP. For the next generation of ultrahigh-efficiency III-V solar cells, we need a new semiconductor which is lattice-matched to GaAs, has a band gap of 1 eV, and has long minority-carrier diffusion lengths. Out of a number of candidate materials, the recently-discovered alloy GaInNAs appears to have the greatest promise. This material satisfies the first two criteria, but has to date shown very low diffusion lengths, a problem which is our current focus in the development of these next-generation cells.

  5. Breakthrough Furnace Can Cut Solar Industry Costs

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

    Furnace can Cut Solar Industry Costs A game-changing Optical Cavity Furnace (OCF)-developed by the National Renew- able Energy Laboratory (NREL) with funding from the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy-uses optics to heat and purify solar cells at unmatched precision, while also boosting the cells' efficiency. As solar cells move through a manufacturer's production line, they must be oxidized, annealed, purified, diffused, etched, and layered. Heat is an

  6. Inverted amorphous silicon solar cell utilizing cermet layers

    DOE Patents [OSTI]

    Hanak, Joseph J.

    1979-01-01

    An amorphous silicon solar cell incorporating a transparent high work function metal cermet incident to solar radiation and a thick film cermet contacting the amorphous silicon opposite to said incident surface.

  7. Control of a solar pond

    SciTech Connect (OSTI)

    Sherman, B.S.; Imberger, J. )

    1991-01-01

    Solar ponds hold the promise of providing an alternative to diesel generation of electricity at remote locations in Australia where fuel costs are high. However, to reliably generate electricity with a solar pond requires high temperatures to be maintained throughout the year; this goal had eluded the Alice Springs solar pond prior to 1989 because of double-diffusive convection within the gradient zone. This paper presents control strategies designed to provide successful high temperature operation of a solar pond year-round. The strategies, which consist mainly of manipulating upper surface layer salinity and extracting heat from the storage zone are well suited to automation. They were tested at the Alice Springs solar pond during the summer of 1989 and maintained temperatures in excess of 85{degree}C for several months without any gradient stability problems.

  8. Nevada Solar One Solar Power Plant | Open Energy Information

    Open Energy Info (EERE)

    Solar One Solar Power Plant Jump to: navigation, search Name Nevada Solar One Solar Power Plant Facility Nevada Solar One Sector Solar Facility Type Concentrating Solar Power...

  9. Mojave Solar Park Solar Power Plant | Open Energy Information

    Open Energy Info (EERE)

    Solar Park Solar Power Plant Jump to: navigation, search Name Mojave Solar Park Solar Power Plant Facility Mojave Solar Park Sector Solar Facility Type Concentrating Solar Power...

  10. Starwood Solar I Solar Power Plant | Open Energy Information

    Open Energy Info (EERE)

    Starwood Solar I Solar Power Plant Jump to: navigation, search Name Starwood Solar I Solar Power Plant Facility Starwood Solar I Sector Solar Facility Type Concentrating Solar...

  11. ARM - Measurement - Photosynthetically Active Radiation

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

    govMeasurementsPhotosynthetically Active Radiation ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Photosynthetically Active Radiation Photosynthetically Active Radiation (PAR) designates the spectral range (wave band) of solar radiation from 400 to 700 nanometers that photosynthetic organisms are able to use in the process of photosynthesis Categories Radiometric Instruments The above measurement is

  12. Angular Signatures of Dark Matter in the Diffuse Gamma Ray Spectrum

    SciTech Connect (OSTI)

    Hooper, Dan; Serpico, Pasquale D.; /Fermilab

    2007-02-01

    Dark matter annihilating in our Galaxy's halo and elsewhere in the universe is expected to generate a diffuse flux of gamma rays, potentially observable with next generation satellite-based experiments, such as GLAST. In this article, we study the signatures of dark matter in the angular distribution of this radiation. Pertaining to the extragalactic contribution, we discuss the effect of the motion of the solar system with respect to the cosmological rest frame, and anisotropies due to the structure of our local universe. For the gamma ray flux from dark matter in our own Galactic halo, we discuss the effects of the offset position of the solar system, the Compton-Getting effect, the asphericity of the Milky Way halo, and the signatures of nearby substructure. We explore the prospects for the detection of these features by the GLAST satellite and find that, if {approx} 10% or more of the diffuse gamma ray background observed by EGRET is the result of dark matter annihilations, then GLAST should be sensitive to anisotropies down to the 0.1% level. Such precision would be sufficient to detect many, if not all, of the signatures discussed in this paper.

  13. Analysis of clear hour solar irradiation for seven Canadian stations

    SciTech Connect (OSTI)

    Garrison, J.; Sahami, K.

    1995-12-31

    Hourly global and diffuse irradiation and corresponding surface meteorological data have been analyzed for the seven Canadian stations at Edmonton, Goose Bay, Montreal, Port Hardy, Resolute, Toronto, and Winnipeg. The variation of the most probable clear hour values of clearness index k{sub t}, diffuse index k{sub d}, direct beam index k{sub b}, and Angstrom turbidity coefficient {beta} with solar elevation, atmospheric precipitable water, and snow depth are obtained. Values of these quantities are presented which are consistent with the attenuation and scattering of solar radiation by the atmosphere which is expected. The most probable values of {beta} tend to be lower than the average values of {beta} recently reported by Gueymard. The data indicate a drift in the calibration of the instruments used for measurements of the irradiation data for the stations at Goose Bay and Resolute. The data for the other five stations indicate that the instrument calibration is maintained over the years of the data. 4 refs., 8 figs., 5 tabs.

  14. Radiation receiver

    DOE Patents [OSTI]

    Hunt, Arlon J.

    1983-01-01

    The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles.

  15. Radiation receiver

    DOE Patents [OSTI]

    Hunt, A.J.

    1983-09-13

    The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles. 5 figs.

  16. Electron-hole diffusion lengths >175 μm in solution-grown CH3NH3PbI3 single crystals

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

    Dong, Qingfeng; Fang, Yanjun; Shao, Yuchuan; Mulligan, Padhraic; Qiu, Jie; Cao, Lei; Huang, Jinsong

    2015-02-27

    Long, balanced electron and hole diffusion lengths greater than 100 nanometers in the polycrystalline organolead trihalide compound CH3NH3PbI3 are critical for highly efficient perovskite solar cells. We found that the diffusion lengths in CH3NH3PbI3 single crystals grown by a solution-growth method can exceed 175 micrometers under 1 sun (100 mW cm–2) illumination and exceed 3 millimeters under weak light for both electrons and holes. The internal quantum efficiencies approach 100% in 3-millimeter-thick single-crystal perovskite solar cells under weak light. These long diffusion lengths result from greater carrier mobility, longer lifetime, and much smaller trap densities in the single crystals thanmore » in polycrystalline thin films. As a result, the long carrier diffusion lengths enabled the use of CH3NH3PbI3 in radiation sensing and energy harvesting through the gammavoltaic effect, with an efficiency of 3.9% measured with an intense cesium-137 source.« less

  17. Electron-hole diffusion lengths >175 μm in solution-grown CH3NH3PbI3 single crystals

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

    Dong, Qingfeng; Fang, Yanjun; Shao, Yuchuan; Mulligan, Padhraic; Qiu, Jie; Cao, Lei; Huang, Jinsong

    2015-02-27

    Long, balanced electron and hole diffusion lengths greater than 100 nanometers in the polycrystalline organolead trihalide compound CH3NH3PbI3 are critical for highly efficient perovskite solar cells. We found that the diffusion lengths in CH3NH3PbI3 single crystals grown by a solution-growth method can exceed 175 micrometers under 1 sun (100 mW cm–2) illumination and exceed 3 millimeters under weak light for both electrons and holes. The internal quantum efficiencies approach 100% in 3-millimeter-thick single-crystal perovskite solar cells under weak light. These long diffusion lengths result from greater carrier mobility, longer lifetime, and much smaller trap densities in the single crystals thanmore »in polycrystalline thin films. As a result, the long carrier diffusion lengths enabled the use of CH3NH3PbI3 in radiation sensing and energy harvesting through the gammavoltaic effect, with an efficiency of 3.9% measured with an intense cesium-137 source.« less

  18. Solar Power

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

    Solar Power Solar Power Project Opportunities Abound in the Region The WIPP site is receives abundant solar energy with 6-7 kWh/sq meter power production potential As the accompanying map of New Mexico shows, the WIPP site enjoys abundant year-round sunshine. With an average solar power production potential of 6-7 kWh/sq meter per day, one exciting project being studied for location at WIPP is a 30-50 MW Solar Power Tower: The American Solar Energy Society (ASES) is is a national trade

  19. Microfabricated diffusion source

    DOE Patents [OSTI]

    Oborny, Michael C.; Frye-Mason, Gregory C.; Manginell, Ronald P.

    2008-07-15

    A microfabricated diffusion source to provide for a controlled diffusion rate of a vapor comprises a porous reservoir formed in a substrate that can be filled with a liquid, a headspace cavity for evaporation of the vapor therein, a diffusion channel to provide a controlled diffusion of the vapor, and an outlet to release the vapor into a gas stream. The microfabricated diffusion source can provide a calibration standard for a microanalytical system. The microanalytical system with an integral diffusion source can be fabricated with microelectromechanical systems technologies.

  20. Nanocrystal Solar Cells

    SciTech Connect (OSTI)

    Gur, Ilan

    2006-12-15

    This dissertation presents the results of a research agenda aimed at improving integration and stability in nanocrystal-based solar cells through advances in active materials and device architectures. The introduction of 3-dimensional nanocrystals illustrates the potential for improving transport and percolation in hybrid solar cells and enables novel fabrication methods for optimizing integration in these systems. Fabricating cells by sequential deposition allows for solution-based assembly of hybrid composites with controlled and well-characterized dispersion and electrode contact. Hyperbranched nanocrystals emerge as a nearly ideal building block for hybrid cells, allowing the controlled morphologies targeted by templated approaches to be achieved in an easily fabricated solution-cast device. In addition to offering practical benefits to device processing, these approaches offer fundamental insight into the operation of hybrid solar cells, shedding light on key phenomena such as the roles of electrode-contact and percolation behavior in these cells. Finally, all-inorganic nanocrystal solar cells are presented as a wholly new cell concept, illustrating that donor-acceptor charge transfer and directed carrier diffusion can be utilized in a system with no organic components, and that nanocrystals may act as building blocks for efficient, stable, and low-cost thin-film solar cells.

  1. ImagineSolar | Open Energy Information

    Open Energy Info (EERE)

    Workforce training, Corporate consulting - Solar projects, Solar sales, Solar marketing, Solar business development, Solar policy, Solar advocacy, Solar government...

  2. Solar Manufacturing Projects | Department of Energy

    Office of Environmental Management (EM)

    Solar Manufacturing Projects Solar Manufacturing Projects Solar Manufacturing Projects Solar Manufacturing Projects Solar Manufacturing Projects Solar Manufacturing Projects SOLAR ...

  3. Solar Energy Education. Renewable energy activities for junior high/middle school science

    SciTech Connect (OSTI)

    Not Available

    1985-01-01

    Some basic topics on the subject of solar energy are outlined in the form of a teaching manual. The manual is geared toward junior high or middle school science students. Topics include solar collectors, solar water heating, solar radiation, insulation, heat storage, and desalination. Instructions for the construction of apparatus to demonstrate the solar energy topics are provided. (BCS)

  4. Solar Rights

    Broader source: Energy.gov [DOE]

    A solar energy system is defined as "a system affixed to a building or buildings that uses solar devices, which are thermally isolated from living space or any other area where the energy is used...

  5. Solar Blog

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

    96426 Solar Blog en Solar Energy Jobs Outpace U.S. Economy http:energy.govarticlessolar-energy-jobs-outpace-us-economy

  6. Solar Rights

    Broader source: Energy.gov [DOE]

    In the context of this law, a solar energy device is a system "manufactured and sold for the sole purpose of facilitating the collection and beneficial use of solar energy, including passive...

  7. Solar Forecasting

    Broader source: Energy.gov [DOE]

    On December 7, 2012, DOE announced $8 million to fund two solar projects that are helping utilities and grid operators better forecast when, where, and how much solar power will be produced at U.S....

  8. OSTIblog Articles in the solar Topic | OSTI, US Dept of Energy...

    Office of Scientific and Technical Information (OSTI)

    ... DOE Green Energy site, offers more information on the SunShot Initiative Additional Resources: Solar Energy Evolution and Diffusion Studies (SEEDS) Award Selections SunShot ...

  9. Watt-Sun: A Multi-Scale, Multi-Model, Machine-Learning Solar...

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

    APPROACH watt sun diffusive irradiance gif w key.gif Similar to the recently demonstrated ... solar forecasting technology (short: Watt-sun), which leverages new data processing ...

  10. Solar collectors

    SciTech Connect (OSTI)

    Cassidy, V.M.

    1981-11-01

    Practical applications of solar energy in commercial, industrial and institutional buildings are considered. Two main types of solar collectors are described: flat plate collectors and concentrating collectors. Efficiency of air and hydronic collectors among the flat plate types are compared. Also several concentrators are described, including their sun tracking mechanisms. Descriptions of some recent solar installations are presented and a list representing the cross section of solar collector manufacturers is furnished.

  11. Solar Energy Education. Renewable energy activities for earth science

    SciTech Connect (OSTI)

    Not Available

    1980-01-01

    A teaching manual is provided to aid teachers in introducing renewable energy topics to earth science students. The main emphasis is placed on solar energy. Activities for the student include a study of the greenhouse effect, solar gain for home heating, measuring solar radiation, and the construction of a model solar still to obtain fresh water. Instructions for the construction of apparatus to demonstrate a solar still, the greenhouse effect and measurement of the altitude and azimuth of the sun are included. (BCS)

  12. Central solar energy receiver

    DOE Patents [OSTI]

    Drost, M. Kevin

    1983-01-01

    An improved tower-mounted central solar energy receiver for heating air drawn through the receiver by an induced draft fan. A number of vertically oriented, energy absorbing, fin-shaped slats are radially arranged in a number of concentric cylindrical arrays on top of the tower coaxially surrounding a pipe having air holes through which the fan draws air which is heated by the slats which receive the solar radiation from a heliostat field. A number of vertically oriented and wedge-shaped columns are radially arranged in a number of concentric cylindrical clusters surrounding the slat arrays. The columns have two mirror-reflecting sides to reflect radiation into the slat arrays and one energy absorbing side to reduce reradiation and reflection from the slat arrays.

  13. Apparatus for solar coal gasification

    DOE Patents [OSTI]

    Gregg, D.W.

    Apparatus for using focused solar radiation to gasify coal and other carbonaceous materials is described. Incident solar radiation is focused from an array of heliostats onto a tower-mounted secondary mirror which redirects the focused solar radiation down through a window onto the surface of a vertically-moving bed of coal, or a fluidized bed of coal, contained within a gasification reactor. The reactor is designed to minimize contact between the window and solids in the reactor. Steam introduced into the gasification reactor reacts with the heated coal to produce gas consisting mainly of carbon monoxide and hydrogen, commonly called synthesis gas, which can be converted to methane, methanol, gasoline, and other useful products. One of the novel features of the invention is the generation of process steam at the rear surface of the secondary mirror.

  14. Breakthrough Furnace Can Cut Solar Costs - News Feature | NREL

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

    Breakthrough Furnace Can Cut Solar Costs October 21, 2011 In this photo, the cavity inside the furnace is glowing white-hot during a simulated firing, while a drawer-like door is open to show the mouth of the furnace. Enlarge image The cavity inside the Solar Optical Furnace glows white hot during a simulated firing of a solar cell. Credit: Dennis Schroeder Solar cells, the heart of the photovoltaic industry, must be tested for mechanical strength, oxidized, annealed, purified, diffused, etched,

  15. Purchasing Solar Collectively with Solarize

    Broader source: Energy.gov [DOE]

    This video provides an overview of the concept behind The Solarize Guidebook, which offers neighborhoods a plan for getting volume discounts when making group purchases of rooftop solar energy...

  16. Solar heat receiver

    DOE Patents [OSTI]

    Hunt, Arlon J.; Hansen, Leif J.; Evans, David B.

    1985-01-01

    A receiver for converting solar energy to heat a gas to temperatures from 700.degree.-900.degree. C. The receiver is formed to minimize impingement of radiation on the walls and to provide maximum heating at and near the entry of the gas exit. Also, the receiver is formed to provide controlled movement of the gas to be heated to minimize wall temperatures. The receiver is designed for use with gas containing fine heat absorbing particles, such as carbon particles.

  17. Solar heat receiver

    DOE Patents [OSTI]

    Hunt, A.J.; Hansen, L.J.; Evans, D.B.

    1982-09-29

    A receiver is described for converting solar energy to heat a gas to temperatures from 700 to 900/sup 0/C. The receiver is formed to minimize impingement of radiation on the walls and to provide maximum heating at and near the entry of the gas exit. Also, the receiver is formed to provide controlled movement of the gas to be heated to minimize wall temperatures. The receiver is designed for use with gas containing fine heat absorbing particles, such as carbon particles.

  18. High-Flux Microchannel Solar Receiver

    Broader source: Energy.gov [DOE]

    This fact sheet describes a high-flux, microchannel solar receiver project awarded under the DOE's 2012 SunShot Concentrating Solar Power R&D award program. The team, led by Oregon State University, is working to demonstrate a microchannel-based solar receiver capable of absorbing high solar flux, while using a variety of liquid and gaseous working fluids. High-flux microchannel receivers have the potential to dramatically reduce the size and cost of a solar receiver by minimizing re-radiation and convective losses.

  19. CHEMISTRY IN DIFFUSE CLOUDS WITH TRANSIENT MICROSTRUCTURE

    SciTech Connect (OSTI)

    Cecchi-Pestellini, C.; Casu, S.; Williams, D. A.; Viti, S.

    2009-12-01

    Microstructure is observed on many lines of sight in the diffuse interstellar medium, mainly through variations in atomic line absorptions on timescales of a decade or less. This timescale implies that microstructure exists on a size scale comparable with that of the solar system; it is overpressured and transient. Both observations and theory confirm that a specific chemistry occurs in microstructure. We therefore explore a model of diffuse interstellar gas in which the chemistry in diffuse clouds is supplemented by chemistry in many transient and tiny perturbations. These perturbations are here assumed to be of unidentified origin, but it is assumed that ambipolar diffusion occurs within them. For plausible physical parameters, we find that this model can account for the range of molecular column densities observed in diffuse clouds, including species not usually accounted for by conventional models. Some molecular ions, predicted to be generated in the microstructure (including HS{sup +}, CH{sup +} {sub 2}, CH{sup +} {sub 3}, H{sub 2}O{sup +}, and H{sub 3}O{sup +}) but not yet observed in diffuse clouds, should be present at levels that may allow their detection.

  20. Comment on “Towards high efficiency thin-film crystalline silicon solar cells: The roles of light trapping and non-radiative recombinations” [J. Appl. Phys. 115, 094501 (2014)

    SciTech Connect (OSTI)

    Abenante, L.

    2015-01-14

    In the above paper, an analytical approach including a new solution to the differential diffusion equation in illuminated quasi-neutral regions (QNR) is exploited to calculate the short-circuit current density (J{sub sc}), open-circuit voltage (V{sub oc}), fill factor (FF), and efficiency (η) of light-trapping (LT) c-Si solar cells with a given structure. Comparisons with numerical results calculated by the Silvaco ATLAS device simulator in the same LT cells show that the analytical results are systematically overestimated. According to the authors, the inaccuracies in J{sub sc}, V{sub oc}, and η are due to the fact that assuming ideal collection from space-charge region (SCR) and using the superposition approximation introduce systematic errors into analytical models. In this comment, an analytical approach using reported solutions to the transport equations in QNR and SCR, where ideal collection from SCR is assumed and the superposition approximation is used, is shown to agree with both the Silvaco and PC1d numerical approaches in calculating J{sub sc}, V{sub oc}, and η, in the same LT devices as considered in the commented paper. Reasons for the inaccuracies detected in the commented paper are suggested.

  1. Method and global relationship for estimation of transmitted solar energy distribution in passive solar rooms

    SciTech Connect (OSTI)

    Athienitis, A.K.; Stylianou, M. )

    1991-01-01

    Estimation of the distribution of transmitted solar radiation within a room with large windows is required for correct prediction of building thermal performance and for optimal positioning of the thermal storage mass. This article presents a detailed computer method that determines the instantaneous solar radiation transmitted through a window and absorbed by each room interior surface, and a correlation for estimating the fraction of daily total transmitted solar radiation absorbed by the floor for several latitudes, for different shapes of enclosures, and for varying surface solar absorptances. The correlation was developed by fitting an exponential relationship to results obtained from a numerical study of the variation of the following parameters influencing the distribution of solar radiation: latitude, day of year, geometry of enclosure (width-to-depth ratio and window azimuth angle), window-to-floor area ratio, and surface absorptances.

  2. Extracting Cu Diffusion Parameters in Polycrystalline CdTe

    SciTech Connect (OSTI)

    Akis, Richard; Brinkman, Daniel; Sankin, Igor; Fang, Tian; Guo, Da; Dragica, Vasileska; Ringhofer, Christian

    2014-06-13

    It is well known that Cu plays an important role in CdTe solar cell performance as a dopant. In this work, a finite-difference method is developed and used to simulate Cu diffusion in CdTe solar cells. In the simulations, which are done on a two-dimensional (2D) domain, the CdTe is assumed to be polycrystal-line, with the individual grains separated by grain boundaries. When used to fit experimental Cu concentration data, bulk and grain boundary diffusion coefficients and activation energies for CdTe can be extracted. In the past, diffusion coefficients have been typically obtained by fitting data to simple functional forms of limited validity. By doing full simulations, the simplifying assumptions used in those analytical models are avoided and diffusion parameters can thus be determined more accurately.

  3. Beacon Solar Energy Project Solar Power Plant | Open Energy Informatio...

    Open Energy Info (EERE)

    Solar Energy Project Solar Power Plant Jump to: navigation, search Name Beacon Solar Energy Project Solar Power Plant Facility Beacon Solar Energy Project Sector Solar Facility...

  4. Prescott Airport Solar Plant Solar Power Plant | Open Energy...

    Open Energy Info (EERE)

    Prescott Airport Solar Plant Solar Power Plant Jump to: navigation, search Name Prescott Airport Solar Plant Solar Power Plant Facility Prescott Airport Solar Plant Sector Solar...

  5. Deming Solar Plant Solar Power Plant | Open Energy Information

    Open Energy Info (EERE)

    Deming Solar Plant Solar Power Plant Jump to: navigation, search Name Deming Solar Plant Solar Power Plant Facility Deming Solar Plant Sector Solar Facility Type Photovoltaic...

  6. SES Calico Solar One Project Solar Power Plant | Open Energy...

    Open Energy Info (EERE)

    Calico Solar One Project Solar Power Plant Jump to: navigation, search Name SES Calico Solar One Project Solar Power Plant Facility SES Calico Solar One Project Sector Solar...

  7. Nvision.Solar - Ravnishte Solar PV Plant | Open Energy Information

    Open Energy Info (EERE)

    Solar - Ravnishte Solar PV Plant Jump to: navigation, search Name Nvision.Solar - Ravnishte Solar PV Plant Facility Ravishte roof and facade mounted solar power plant Sector Solar...

  8. Solar Millenium Palen Solar Power Plant | Open Energy Information

    Open Energy Info (EERE)

    Palen Solar Power Plant Jump to: navigation, search Name Solar Millenium Palen Solar Power Plant Facility Solar Millenium Palen Sector Solar Facility Type Concentrating Solar Power...

  9. SES Solar Two Project Solar Power Plant | Open Energy Information

    Open Energy Info (EERE)

    Two Project Solar Power Plant Jump to: navigation, search Name SES Solar Two Project Solar Power Plant Facility SES Solar Two Project Sector Solar Facility Type Concentrating Solar...

  10. Carrizo Energy Solar Farm Solar Power Plant | Open Energy Information

    Open Energy Info (EERE)

    Carrizo Energy Solar Farm Solar Power Plant Jump to: navigation, search Name Carrizo Energy Solar Farm Solar Power Plant Facility Carrizo Energy Solar Farm Sector Solar Facility...

  11. El Dorado Solar Project Solar Power Plant | Open Energy Information

    Open Energy Info (EERE)

    Solar Project Solar Power Plant Jump to: navigation, search Name El Dorado Solar Project Solar Power Plant Facility El Dorado Solar Project Sector Solar Facility Type Photovoltaic...

  12. Solar | Department of Energy

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

    Science & Innovation Energy Sources Renewable Energy Solar Solar How much do you know about solar power? Take our quiz and test your solar energy IQ. | Photo courtesy of ...

  13. Fabrication of solar cells with counter doping prevention

    DOE Patents [OSTI]

    Dennis, Timothy D; Li, Bo; Cousins, Peter John

    2013-02-19

    A solar cell fabrication process includes printing of dopant sources over a polysilicon layer over backside of a solar cell substrate. The dopant sources are cured to diffuse dopants from the dopant sources into the polysilicon layer to form diffusion regions, and to crosslink the dopant sources to make them resistant to a subsequently performed texturing process. To prevent counter doping, dopants from one of the dopant sources are prevented from outgassing and diffusing into the other dopant source. For example, phosphorus from an N-type dopant source is prevented from diffusing to a P-type dopant source comprising boron.

  14. Amorphous silicon solar cell allowing infrared transmission

    DOE Patents [OSTI]

    Carlson, David E.

    1979-01-01

    An amorphous silicon solar cell with a layer of high index of refraction material or a series of layers having high and low indices of refraction material deposited upon a transparent substrate to reflect light of energies greater than the bandgap energy of the amorphous silicon back into the solar cell and transmit solar radiation having an energy less than the bandgap energy of the amorphous silicon.

  15. Studying the Solar System's Chemical Recipe

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

    Studying the Solar System's Chemical Recipe Studying the Solar System's Chemical Recipe Print Tuesday, 26 March 2013 00:00 To study the origins of different isotope ratios among the elements that make up today's smorgasbord of planets, moons, comets, asteroids, and interplanetary ice and dust, a team of scientists from the University of California, San Diego is using ALS Chemical Dynamics Beamline 9.0.2 to mimic radiation from the protosun when the solar system was forming. For more than three

  16. Solar cell with a gallium nitride electrode

    DOE Patents [OSTI]

    Pankove, Jacques I.

    1979-01-01

    A solar cell which comprises a body of silicon having a P-N junction therein with a transparent conducting N-type gallium nitride layer as an ohmic contact on the N-type side of the semiconductor exposed to solar radiation.

  17. Integrated solar thermal energy collector system

    SciTech Connect (OSTI)

    Garrison, J.D.

    1987-08-18

    A solar thermal collector system is described one of a class of devices which converts solar radiation into heat and transmits this heat to storage from whence it is utilized, comprising: an evacuated glass solar collector, the evacuated glass solar collector having a glass vacuum envelope, the upper portion of the glass vacuum envelope also serving as window to pass solar radiation, the evacuated glass solar collector having a multiplicity of substantially parallel linear adjacent concentrating troughs, each trough shaped and mirror surfaced so as concentrate solar radiation in the vacuum, the mirror surface inside the vacuum and the concentration approximately ideal, the multiplicity of substantially parallel linear adjacent troughs extending substantially over the entire length and width of the evacuated glass solar collector; a heat storage system, the heat storage system adjacent to the evacuated glass solar collector, the heat storage system having a heat storage tank which is thermally insulated, the heat storage tank containing a heat storage medium, and the heat storage system including means of removal of heat from the heat storage tank for utilization.

  18. Diffusion Bonding Characterization

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

    Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal ... Natural Gas Supercritical CO2-Brayton Cycle Geothermal Safety, Security & ...

  19. Solar Newsletter

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

    Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas ...

  20. Solar Mapper

    Broader source: Energy.gov [DOE]

    Interactive, online mapping tool providing access to spatial data related to siting utility-scale solar facilities in the southwestern United States.

  1. Solar Newsletter

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

    Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water ...

  2. Solar Newsletter

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

    Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & ...

  3. Solar Decathlon

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

    ... Administration and DOE EERE International Program: Solar Decathlon China 2013 16 | Building Technologies Office eere.energy.gov Project Integration, Collaboration & Market Impact ...

  4. Solar Rights

    Broader source: Energy.gov [DOE]

    Ordinances, bylaws, or regulations may reasonably restrict the installation and use of solar energy devices to protect public health and safety, buildings from damage, historic/aesthetic values (...

  5. CONFRRM Solar Energy Resource Data: Data from the Cooperative Network for Renewable Resource Measurements

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

    The Cooperative Network for Renewable Resource Measurements (CONFRRM) is a cooperative effort between NREL and other agencies to conduct long-term solar radiation and wind measurements at selected locations in the United States. CONFRRM expands the geographic coverage of measurement locations and provides high quality data for determining site-specific resources, as well as data for the validation and testing of models to predict available resources based on meteorological or satellite data. Twelve sites are currently active in the CONFRRM network. CONFRRM complements and provides additional geographic coverage to the National Oceanic and Atmospheric Administration's (NOAA's) Integrated Surface Irradiance Study (ISIS) network. Solar data elements measured and reported by the CONFRRM sites include global horizontal irradiance (GHI), direct normal irradiance (DNI), diffuse horizontal irradiance (DHI), and global horizontal irradiance measured with a LI-COR pyranometer. Meteorological data include air temperature, relative humidity, pressure, wind speed, wind direction and peak wind speed. Data logger temperature and battery voltage may also be reported. Prior to January 1, 1996, five CONFRRM sites together with South Caroline State College in Orangeburg, South Carolina, made up the Historically Black Colleges and Universities (HBCU) Solar Radiation Monitoring Network, located in the Southeastern United States. In January 1997 the HBCU sites became part of CONFRRM.

  6. Germanium subcells for multijunction GaInP/GaInAs/Ge solar cells

    SciTech Connect (OSTI)

    Kalyuzhnyy, N. A.; Gudovskikh, A. S.; Evstropov, V. V.; Lantratov, V. M.; Mintairov, S. A.; Timoshina, N. Kh.; Shvarts, M. Z.; Andreev, V. M.

    2010-11-15

    Photovoltaic converters based on n-GaInP/n-p-Ge heterostructures grown by the OMVPE under different conditions of formation of the p-n junction are studied. The heterostructures are intended for use as narrow-gap subcells of the GaInP/GaInAs/Ge three-junction solar cells. It is shown that, in Ge p-tn junctions, along with the diffusion mechanism, the tunneling mechanism of the current flow exists; therefore, the two-diode electrical equivalent circuit of the Ge p-n junction is used. The diode parameters are determined for both mechanisms from the analysis of both dark and 'light' current-voltage dependences. It is shown that the elimination of the component of the tunneling current allows one to increase the efficiency of the Ge subcell by {approx}1% with conversion of nonconcentrated solar radiation. The influence of the tunneling current on the efficiency of the Ge-based devices can be in practice reduced to zero at photogenerated current density of {approx}1.5 A/cm{sup 2} due to the use of the concentrated solar radiation.

  7. Tracking and stationary flat plate solar collectors: Yearly collectible energy correlations for photovoltaic applications

    SciTech Connect (OSTI)

    Gordon, J.M. ); Kreider, J.F.; Reeves, P. )

    1991-01-01

    For tracking and stationary flat plate (nonconcentrating) solar collectors, the authors develop easy-to-use, closed form, analytical formulae for yearly collectible energy as a function of radiation threshold. Primary applications include central-station photovoltaic systems. These correlations include the explicit dependence on: yearly average clearness index, latitude, and ground cover ratio (shading effects), and are in excellent agreement with data-based results for 26 US SOLMET stations. They also incorporate appropriate functional forms that ensure accurate results for photovoltaic system design and, in particular, for systems with buy-back thresholds. Both beam and diffuse shading are treated properly and diffuse shading is found to represent a 2%-6% loss that has systematically been ignored in past studies. Sample sensitivity studies illustrate evaluation of the energetic advantage of tracking vs. stationary deployment and its significant dependence on ground cover ratio. The impact of isotropic versus anisotropic modeling of diffuse radiation is quantified and shown to give rise to non-negligible differences (up to 10%) in yearly collectible energy. They also determine an optimal tracking strategy for two-axis trackers which, however, is found to yield a 0%-2% energetic advantage relative to conventional normal-incidence tracking.

  8. Alpha Radiation

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

    Basics of Radiation Gamma Radiation and X-Rays Beta Radiation Alpha Radiation Irradiation Radioactive Contamination Definitions Detection Measurement Safety Around Radiation Sources Types of Radiation Exposure Managing Radiation Emergencies Basics of Radiation Characteristics of Alpha Radiation 1. Alpha radiation is not able to penetrate skin. 2. Alpha-emitting materials can be harmful to humans if the materials are inhaled, swallowed, or absorbed through open wounds. 3. A variety of instruments

  9. Radiation Effects In Space

    SciTech Connect (OSTI)

    Tripathi, Ram K.

    2011-06-01

    Protecting space missions from severe exposures from radiation, in general, and long duration/deep space human missions, in particular, is a critical design driver, and could be a limiting factor. The space radiation environment consists of galactic cosmic rays (GCR), solar particle events (SPE), trapped radiation, and includes ions of all the known elements over a very broad energy range. These ions penetrate spacecraft materials producing nuclear fragments and secondary particles that damage biological tissues and microelectronic devices. One is required to know how every element (and all isotopes of each element) in the periodic table interacts and fragments on every other element in the same table as a function of kinetic energy ranging over many decades. In addition, the accuracy of the input information and database, in general and nuclear data in particular, impacts radiation exposure health assessments and payload penalty. After a brief review of effects of space radiation on materials and electronics, human space missions to Mars is discussed.

  10. Project Profile: Forecasting and Influencing Technological Progress in Solar Energy

    Broader source: Energy.gov [DOE]

    The University of North Carolina at Charlotte, along with their partners at Arizona State University and the University of Oxford, under the Solar Energy Evolution and Diffusion Studies (SEEDS)...

  11. A U. S. Department of Energy User Facility Atmospheric Radiation

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

    U. S. Department of Energy User Facility Atmospheric ... INCOMING SOLAR RADIATION Surface Instruments REFLECTED ... Unfortunately, many of these useful datasets reside with the ...

  12. Deep-level defects introduced by 1 MeV electron radiation in AlInGaP for multijunction space solar cells

    SciTech Connect (OSTI)

    Lee, H.S.; Yamaguchi, M.; Ekins-Daukes, N. J.; Khan, A.; Takamoto, T.; Agui, T.; Kamimura, K.; Kaneiwa, M.; Imaizumi, M.; Ohshima, T.; Itoh, H.

    2005-11-01

    Presented in this paper are 1 MeV electron irradiation effects on wide-band-gap (1.97 eV) (Al{sub 0.08}Ga{sub 0.92}){sub 0.52}In{sub 0.48}P diodes and solar cells. The carrier removal rate estimated in p-AlInGaP with electron fluence is about 1 cm{sup -1}, which is lower than that in InP and GaAs. From high-temperature deep-level transient spectroscopy measurements, a deep-level defect center such as majority-carrier (hole) trap H2 (E{sub {nu}}+0.90{+-}0.05 eV) was observed. The changes in carrier concentrations ({delta}p) and trap densities as a function of electron fluence were compared, and as a result the total introduction rate, 0.39 cm{sup -1}, of majority-carrier trap centers (H1 and H2) is different from the carrier removal rate, 1 cm{sup -1}, in p-AlInGaP. From the minority-carrier injection annealing (100 mA/cm{sup 2}), the annealing activation energy of H2 defect is {delta}E=0.60 eV, which is likely to be associated with a vacancy-phosphorus Frenkel pair (V{sub p}-P{sub i}). The recovery of defect concentration and carrier concentration in the irradiated p-AlInGaP by injection relates that a deep-level defect H2 acts as a recombination center as well as compensator center.

  13. Solar-Geophysical Data Number 537, May 1989. Part 2 (comprehensive reports). Data for November 1988 and miscellaneous

    SciTech Connect (OSTI)

    Coffey, H.E.

    1987-07-01

    Solar data are presented for November 1988. The data include solar flares in the H-alpha line; solar radio bursts at fixed frequencies; interplanetary solar particles and plasma; solar x-ray radiation as seen from the GOES-7 artificial satellite; mass ejections from the sun; and active prominences and filaments.

  14. Electron-hole diffusion lengths >175 μm in solution-grown CH3NH3PbI3 single crystals

    SciTech Connect (OSTI)

    Dong, Qingfeng; Fang, Yanjun; Shao, Yuchuan; Mulligan, Padhraic; Qiu, Jie; Cao, Lei; Huang, Jinsong

    2015-02-27

    Long, balanced electron and hole diffusion lengths greater than 100 nanometers in the polycrystalline organolead trihalide compound CH3NH3PbI3 are critical for highly efficient perovskite solar cells. We found that the diffusion lengths in CH3NH3PbI3 single crystals grown by a solution-growth method can exceed 175 micrometers under 1 sun (100 mW cm–2) illumination and exceed 3 millimeters under weak light for both electrons and holes. The internal quantum efficiencies approach 100% in 3-millimeter-thick single-crystal perovskite solar cells under weak light. These long diffusion lengths result from greater carrier mobility, longer lifetime, and much smaller trap densities in the single crystals than in polycrystalline thin films. As a result, the long carrier diffusion lengths enabled the use of CH3NH3PbI3 in radiation sensing and energy harvesting through the gammavoltaic effect, with an efficiency of 3.9% measured with an intense cesium-137 source.

  15. Unified Solar

    Broader source: Energy.gov [DOE]

    Unified Solar is an MIT startup that is commercializing an integrated circuit solution that eliminates most of the adverse effects caused by partial shading in photovoltaic power systems. With its patent-pending design, Unified Solar's solution is smaller, cheaper and more powerful than any competing power optimizer in the market.

  16. Cosmology with matter diffusion

    SciTech Connect (OSTI)

    Calogero, Simone; Velten, Hermano E-mail: velten@cce.ufes.br

    2013-11-01

    We construct a viable cosmological model based on velocity diffusion of matter particles. In order to ensure the conservation of the total energy-momentum tensor in the presence of diffusion, we include a cosmological scalar field ? which we identify with the dark energy component of the universe. The model is characterized by only one new degree of freedom, the diffusion parameter ?. The standard ?CDM model can be recovered by setting ? = 0. If diffusion takes place (? > 0) the dynamics of the matter and of the dark energy fields are coupled. We argue that the existence of a diffusion mechanism in the universe may serve as a theoretical motivation for interacting models. We constrain the background dynamics of the diffusion model with Supernovae, H(z) and BAO data. We also perform a perturbative analysis of this model in order to understand structure formation in the universe. We calculate the impact of diffusion both on the CMB spectrum, with particular attention to the integrated Sachs-Wolfe signal, and on the matter power spectrum P(k). The latter analysis places strong constraints on the magnitude of the diffusion mechanism but does not rule out the model.

  17. Thermal efficiency of single-pass solar air collector

    SciTech Connect (OSTI)

    Ibrahim, Zamry; Ibarahim, Zahari; Yatim, Baharudin; Ruslan, Mohd Hafidz

    2013-11-27

    Efficiency of a finned single-pass solar air collector was studied. This paper presents the experimental study to investigate the effect of solar radiation and mass flow rate on efficiency. The fins attached at the back of absorbing plate to improve the thermal efficiency of the system. The results show that the efficiency is increased proportional to solar radiation and mass flow rate. Efficiency of the collector archived steady state when reach to certain value or can be said the maximum performance.

  18. Laser processing of solar cells with anti-reflective coating

    DOE Patents [OSTI]

    Harley, Gabriel; Smith, David D.; Dennis, Tim; Waldhauer, Ann; Kim, Taeseok; Cousins, Peter John

    2016-02-16

    Contact holes of solar cells are formed by laser ablation to accommodate various solar cell designs. Use of a laser to form the contact holes is facilitated by replacing films formed on the diffusion regions with a film that has substantially uniform thickness. Contact holes may be formed to deep diffusion regions to increase the laser ablation process margins. The laser configuration may be tailored to form contact holes through dielectric films of varying thicknesses.

  19. Sandia Energy - Solar Resource Assessment

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

    Solar Resource Assessment Home Stationary Power Energy Conversion Efficiency Solar Energy Photovoltaics Solar Resource Assessment Solar Resource AssessmentTara...

  20. Sandia Energy - Solar Market Transformation

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

    Solar Market Transformation Home Stationary Power Energy Conversion Efficiency Solar Energy Photovoltaics Solar Market Transformation Solar Market TransformationTara...

  1. Glass Membrane For Controlled Diffusion Of Gases

    DOE Patents [OSTI]

    Shelby, James E.; Kenyon, Brian E.

    2001-05-15

    A glass structure for controlled permeability of gases includes a glass vessel. The glass vessel has walls and a hollow center for receiving a gas. The glass vessel contains a metal oxide dopant formed with at least one metal selected from the group consisting of transition metals and rare earth metals for controlling diffusion of the gas through the walls of the glass vessel. The vessel releases the gas through its walls upon exposure to a radiation source.

  2. Diffuse-dynamic multiparameter diffractometry: A review

    SciTech Connect (OSTI)

    Molodkin, V. B. Shpak, A. P.; Kovalchuk, M. V.; Nosik, V. L.; Machulin, V. F.

    2010-12-15

    The results reported at the Conference on Application of X-Rays, Synchrotron Radiation, Neutrons, and Electrons in Nano-, Bio-, Information-, and Cognitive Technologies (RSNE-NBIC 2009) are briefly reviewed. This review is based on a cycle of studies [1-6] where a new method for studying the structure of real crystals-diffuse-dynamic multiparameter diffractometry (DDMD)-was proposed and substantiated.

  3. A method for estimating direct normal solar irradiation from satellite data for a tropical environment

    SciTech Connect (OSTI)

    Janjai, Serm

    2010-09-15

    In order to investigate a potential use of concentrating solar power technologies and select an optimum site for these technologies, it is necessary to obtain information on the geographical distribution of direct normal solar irradiation over an area of interest. In this work, we have developed a method for estimating direct normal irradiation from satellite data for a tropical environment. The method starts with the estimation of global irradiation on a horizontal surface from MTSAT-1R satellite data and other ground-based ancillary data. Then a satellite-based diffuse fraction model was developed and used to estimate the diffuse component of the satellite-derived global irradiation. Based on this estimated global and diffuse irradiation and the solar radiation incident angle, the direct normal irradiation was finally calculated. To evaluate its performance, the method was used to estimate the monthly average hourly direct normal irradiation at seven pyrheliometer stations in Thailand. It was found that values of monthly average hourly direct normal irradiation from the measurements and those estimated from the proposed method are in reasonable agreement, with a root mean square difference of 16% and a mean bias of -1.6%, with respect to mean measured values. After the validation, this method was used to estimate the monthly average hourly direct normal irradiation over Thailand by using MTSAT-1R satellite data for the period from June 2005 to December 2008. Results from the calculation were displayed as hourly and yearly irradiation maps. These maps reveal that the direct normal irradiation in Thailand was strongly affected by the tropical monsoons and local topography of the country. (author)

  4. NREL: International Activities - India Solar Resource Maps & Data

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

    International Activities Printable Version A button that leads to NREL's National Solar Radiation Database (NSRDB) India Solar Resoource - Annual Average DNI Map Annual Average DNI Map JPG 12.5 MB India Annual Average GHI Map - Annual Average GHI Map Annual Average GHI Map JPG 13.3 MB The cover page of the India Solar Resource Data Fact Sheet India Solar Resource Data Fact Sheet PDF 395 KB India Solar Resource Maps & Data (updated March 2016) This page provides solar resource maps and data

  5. The chemical composition of the sun from helioseismic and solar neutrino data

    SciTech Connect (OSTI)

    Villante, Francesco L.; Serenelli, Aldo M.; Delahaye, Franck; Pinsonneault, Marc H.

    2014-05-20

    We perform a quantitative analysis of the solar composition problem by using a statistical approach that allows us to combine the information provided by helioseismic and solar neutrino data in an effective way. We include in our analysis the helioseismic determinations of the surface helium abundance and of the depth of the convective envelope, the measurements of the {sup 7}Be and {sup 8}B neutrino fluxes, and the sound speed profile inferred from helioseismic frequencies. We provide all the ingredients to describe how these quantities depend on the solar surface composition, different from the initial and internal composition due to the effects of diffusion and nuclear reactions, and to evaluate the (correlated) uncertainties in solar model predictions. We include error sources that are not traditionally considered such as those from inversion of helioseismic data. We, then, apply the proposed approach to infer the chemical composition of the Sun. Our result is that the opacity profile of the Sun is well constrained by the solar observational properties. In the context of a two-parameter analysis in which elements are grouped as volatiles (i.e., C, N, O, and Ne) and refractories (i.e., Mg, Si, S, and Fe), the optimal surface composition is found by increasing the abundance of volatiles by (45 4)% and that of refractories by (19 3)% with respect to the values provided by Asplund et al. (2009, ARA and A, 47, 481). This corresponds to the abundances ?{sub O} = 8.85 0.01 and ?{sub Fe} = 7.52 0.01, which are consistent at the ?1? level with those provided by Grevesse and Sauval (1998, SSRv, 85, 161). As an additional result of our analysis, we show that the best fit to the observational data is obtained with values of input parameters of the standard solar models (radiative opacities, gravitational settling rate, and the astrophysical factors S {sub 34} and S {sub 17}) that differ at the ?1? level from those presently adopted.

  6. Solar Two

    SciTech Connect (OSTI)

    Not Available

    1998-04-01

    Solar Two is a concentrating solar power plant that can supply electric power on demand to the local utility, Southern California Edison Company. It can do so because it operates not only during sunny parts of the day, but it can store enough thermal energy from the sun to operate during cloudy periods and after dark, for up to three hours, at its rated output of 10 megawatts (MW). For the first time ever, a utility scale solar power plant can supply electricity when the utility needs it most, to satisfy the energy requirements of its customers.

  7. Solar Millenium Ridgecrest Solar Power Plant | Open Energy Information

    Open Energy Info (EERE)

    Ridgecrest Solar Power Plant Jump to: navigation, search Name Solar Millenium Ridgecrest Solar Power Plant Facility Solar Millenium Ridgecrest Sector Solar Facility Type...

  8. SES Solar Three Project Solar Power Plant | Open Energy Information

    Open Energy Info (EERE)

    Three Project Solar Power Plant Jump to: navigation, search Name SES Solar Three Project Solar Power Plant Facility SES Solar Three Project Sector Solar Facility Type Photovoltaics...

  9. Renewable Energy Concepts Solar Inc REC Solar | Open Energy Informatio...

    Open Energy Info (EERE)

    Concepts Solar Inc REC Solar Jump to: navigation, search Name: Renewable Energy Concepts Solar Inc (REC Solar) Place: San Luis Obispo, California Zip: 93401 Sector: Solar Product:...

  10. Concentrated Solar Thermoelectric Power

    SciTech Connect (OSTI)

    Chen, Gang; Ren, Zhifeng

    2015-07-09

    The goal of this project is to demonstrate in the lab that solar thermoelectric generators (STEGs) can exceed 10% solar-to-electricity efficiency, and STEGs can be integrated with phase-change materials (PCM) for thermal storage, providing operation beyond daylight hours. This project achieved significant progress in many tasks necessary to achieving the overall project goals. An accurate Themoelectric Generator (TEG) model was developed, which included realistic treatment of contact materials, contact resistances and radiative losses. In terms of fabricating physical TEGs, high performance contact materials for skutterudite TE segments were developed, along with brazing and soldering methods to assemble segmented TEGs. Accurate measurement systems for determining device performance (in addition to just TE material performance) were built for this project and used to characterize our TEGs. From the optical components’ side, a spectrally selective cermet surface was developed with high solar absorptance and low thermal emittance, with thermal stability at high temperature. A measurement technique was also developed to determine absorptance and total hemispherical emittance at high temperature, and was used to characterize the fabricated spectrally selective surfaces. In addition, a novel reflective cavity was designed to reduce radiative absorber losses and achieve high receiver efficiency at low concentration ratios. A prototype cavity demonstrated that large reductions in radiative losses were possible through this technique. For the overall concentrating STEG system, a number of devices were fabricated and tested in a custom built test platform to characterize their efficiency performance. Additionally, testing was performed with integration of PCM thermal storage, and the storage time of the lab scale system was evaluated. Our latest testing results showed a STEG efficiency of 9.6%, indicating promising potential for high performance concentrated STEGs.

  11. Solar Rights

    Broader source: Energy.gov [DOE]

    In June of 2015, SB 1626 was signed into law. It provides that during the development period, the developer may only prohibit  a property owner from installing solar in developments with 50 or...

  12. solar energy

    National Nuclear Security Administration (NNSA)

    8%2A en Solar power purchase for DOE laboratories http:nnsa.energy.govmediaroompressreleasessolarpower

  13. solar power

    National Nuclear Security Administration (NNSA)

    9%2A en Solar power purchase for DOE laboratories http:nnsa.energy.govmediaroompressreleasessolarpower

  14. Detection of solar events

    DOE Patents [OSTI]

    Fischbach, Ephraim; Jenkins, Jere

    2013-08-27

    A flux detection apparatus can include a radioactive sample having a decay rate capable of changing in response to interaction with a first particle or a field, and a detector associated with the radioactive sample. The detector is responsive to a second particle or radiation formed by decay of the radioactive sample. The rate of decay of the radioactive sample can be correlated to flux of the first particle or the field. Detection of the first particle or the field can provide an early warning for an impending solar event.

  15. Project Profile: Helios: Understanding Solar Evolution through Text

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

    Analytics | Department of Energy Soft Costs » Project Profile: Helios: Understanding Solar Evolution through Text Analytics Project Profile: Helios: Understanding Solar Evolution through Text Analytics Logo of SRI International. SRI International, under the Solar Energy Evolution and Diffusion Studies (SEEDS) program, is developing a new system for large-scale text analytics, called Helios, to isolate and map recurring patterns of technology evolution through the inspection of thousands of

  16. Posters Radiation Singularities, Multiple Scattering

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

    3 Posters Radiation Singularities, Multiple Scattering and Diffusion in Multifractal Clouds P. Silas, G. Brösamlen, and S. Lovejoy Department of Physics McGill University Montreal, Quebec, Canada C. Naud and D. Schertzer Université Pierre and Marie Curie Paris, France B. Watson Department of Physics St. Lawrence University Canton, New York Diffusion on One-Dimensional Multifractals (P. Silas, S. Lovejoy, D. Schertzer) Many geophysical and atmospheric fields exhibit multifractal characteristics

  17. Nodal Diffusion & Transport Theory

    Energy Science and Technology Software Center (OSTI)

    1992-02-19

    DIF3D solves multigroup diffusion theory eigenvalue, adjoint, fixed source, and criticality (concentration, buckling, and dimension search) problems in 1, 2, and 3-space dimensions for orthogonal (rectangular or cylindrical), triangular, and hexagonal geometries. Anisotropic diffusion theory coefficients are permitted. Flux and power density maps by mesh cell and regionwise balance integrals are provided. Although primarily designed for fast reactor problems, upscattering and internal black boundary conditions are also treated.

  18. Oxford Solar | Open Energy Information

    Open Energy Info (EERE)

    Oxford Solar Jump to: navigation, search Name: Oxford Solar Place: Randolph, New Jersey Zip: 7869 Sector: Solar Product: Oxford Solar provides solar energy consulting and...

  19. SBM Solar | Open Energy Information

    Open Energy Info (EERE)

    search Name: SBM Solar Place: North Carolina Sector: Solar Product: SBM Solar is a solar panel manufacturer based in North Carolina. References: SBM Solar1 This article is...

  20. Akeena Solar | Open Energy Information

    Open Energy Info (EERE)

    Akeena Solar Jump to: navigation, search Logo: Akeena Solar Name: Akeena Solar Address: 16005 Los Gatos Blvd. Place: Los Gatos, California Zip: 95032 Sector: Solar Product: Solar...

  1. Adobe Solar | Open Energy Information

    Open Energy Info (EERE)

    Adobe Solar Jump to: navigation, search Logo: Adobe Solar Name: Adobe Solar Place: Denver, Colorado Region: Rockies Area Sector: Solar Product: solar electric systems Phone Number:...

  2. Climatic Solar | Open Energy Information

    Open Energy Info (EERE)

    Climatic Solar Jump to: navigation, search Logo: Climatic Solar Name: Climatic Solar Address: 650 2nd Lane Place: Vero Beach, Florida Zip: 32962 Sector: Solar Product: solar energy...

  3. Tejas Solares | Open Energy Information

    Open Energy Info (EERE)

    Tejas Solares Jump to: navigation, search Name: Tejas Solares Place: Spain Sector: Solar Product: Tejas Solares is a Spain-based company focused on providing solar solutions for...

  4. Front contact solar cell with formed emitter

    DOE Patents [OSTI]

    Cousins, Peter John

    2014-11-04

    A bipolar solar cell includes a backside junction formed by an N-type silicon substrate and a P-type polysilicon emitter formed on the backside of the solar cell. An antireflection layer may be formed on a textured front surface of the silicon substrate. A negative polarity metal contact on the front side of the solar cell makes an electrical connection to the substrate, while a positive polarity metal contact on the backside of the solar cell makes an electrical connection to the polysilicon emitter. An external electrical circuit may be connected to the negative and positive metal contacts to be powered by the solar cell. The positive polarity metal contact may form an infrared reflecting layer with an underlying dielectric layer for increased solar radiation collection.

  5. Front contact solar cell with formed emitter

    DOE Patents [OSTI]

    Cousins, Peter John

    2012-07-17

    A bipolar solar cell includes a backside junction formed by an N-type silicon substrate and a P-type polysilicon emitter formed on the backside of the solar cell. An antireflection layer may be formed on a textured front surface of the silicon substrate. A negative polarity metal contact on the front side of the solar cell makes an electrical connection to the substrate, while a positive polarity metal contact on the backside of the solar cell makes an electrical connection to the polysilicon emitter. An external electrical circuit may be connected to the negative and positive metal contacts to be powered by the solar cell. The positive polarity metal contact may form an infrared reflecting layer with an underlying dielectric layer for increased solar radiation collection.

  6. NREL: Solar STAT Blog -

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

    Outreach Policy Basics Publications Request Assistance Technical Assistance Project Map Solar STAT Blog The Solar STAT blog discusses state and local efforts to develop solar...

  7. Solar Resource Assessment

    Broader source: Energy.gov [DOE]

    DOE solar resource research focuses on understanding historical solar resource patterns and making future predictions, both of which are needed to support reliable power system operation. As solar...

  8. Solar Position Algorithm for Solar Radiation Applications (Revised...

    Office of Scientific and Technical Information (OSTI)

    agency thereof. Available electronically at http:www.osti.govbridge Available for a processing fee to U.S. Department of Energy and its contractors, in paper, from: U.S....

  9. MULTIFUNCTIONAL SOLAR ENERGY SYSTEMS RESEARCH PROJECT

    SciTech Connect (OSTI)

    Byard Wood, Lance Seefeldt, Ronald Sims, Bradley Wahlen, and Dan Dye

    2012-06-29

    The solar energy available within the visible portion of the solar spectrum is about 300 W/m2 (43%) and that available in the UV and IR portion is about 400 W/m2 (57%). This provides opportunities for developing integrated energy systems that capture and use specific wavelengths of the solar spectrum for different purposes. For example: biofuels from photosynthetic microbes use only the visible light; solar cells use a narrow band of the solar spectrum that could be either mostly in the visible or in the IR regions of the solar spectrum, depending on the photovoltaic materials, e.g., gallium antimonide (GaSb) cells utilize predominately IR radiation; and finally, solar panels that heat water utilize a broad range of wavelengths (visible plus IR). The basic idea of this research is that sunlight has many possible end-use applications including both direct use and energy conversion schemes; it is technically feasible to develop multifunctional solar energy systems capable of addressing several end-use needs while increasing the overall solar energy utilization efficiency when compared to single-purpose solar technologies. Such a combination of technologies could lead to more cost-competitive ?multifunctional? systems that add value and broaden opportunities for integrated energy systems. The goal of this research is to increase the overall energy efficacy and cost competitiveness of solar systems. The specific objectives of this research were: 1) Evaluate the efficacy of a combined photobioreactor and electric power system; 2) Improve the reliability and cost effectiveness of hybrid solar lighting systems ? a technology in which sunlight is collected and distributed via optical fibers into the interior of a building; 3) Evaluate the efficacy of using filtered light to increase the production of biomass in photobioreactors and provide more solar energy for other uses; 4) Evaluates several concepts for wavelength shifting such that a greater percentage of the solar

  10. Passive solar design handbook. Volume two of two volumes: passive solar design analysis

    SciTech Connect (OSTI)

    Balcomb, J.D.; Barley, D.; McFarland, R.; Perry, J. Jr.; Wray, W.; Noll, S.

    1980-01-01

    A manual for the design and performance evaluation and analysis of passive solar heating systems is presented. Two passive solar building types are analyzed: direct gain and thermal storage walls. Rules of thumb for the schematic design phase and simplified procedures for the design development phase are described. Analysis methods for the construction documents phase are given. The design procedure for fan-forced rock beds for hybrid systems is presented. Economic analysis methods for passive solar buildings are described. Tables of monthly average solar radiation, temperature, and degree-days for various locations in the US and southern Canada are included. (WHK)

  11. Solar Equipment Certification

    Broader source: Energy.gov [DOE]

    Under the Solar Energy Standards Act of 1976, the Florida Solar Energy Center (FSEC) is responsible for certifying all solar equipment sold in Florida. A manufacturer who wishes to have their solar...

  12. Apparatus for diffusion separation

    DOE Patents [OSTI]

    Nierenberg, William A.; Pontius, Rex B.

    1976-08-10

    1. The method of testing the separation efficiency of porous permeable membranes which comprises causing a stream of a gaseous mixture to flow into contact with one face of a finely porous permeable membrane under such conditions that a major fraction of the mixture diffuses through the membrane, maintaining a rectangular cross section of the gaseous stream so flowing past said membrane, continuously recirculating the gas that diffuses through said membrane and continuously withdrawing the gas that does not diffuse through said membrane and maintaining the volume of said recirculating gas constant by continuously introducing into said continuously recirculating gas stream a mass of gas equivalent to that which is continuously withdrawn from said gas stream and comparing the concentrations of the light component in the entering gas, the withdrawn gas and the recirculated gas in order to determine the efficiency of said membrane.

  13. Creating solar media nets solar tools, publicity

    SciTech Connect (OSTI)

    Brewer, B.

    1980-01-01

    The utilization of locally produced solar tool to gain more access to commercial media is discussed. Central is a strategy of (1) giving commercial media something to report, (2) helping educate the media, and (3) simultaneously impacting that portion of the public which is likely to be most interested. Methods for reaching several target audiences include a Solar Calendar, a Passive Solar Film, a local Solar Directory, a local Solar Information Center, an Emergency Coolth brochure and a Conservation/Solar Retrofit Guide.

  14. Solar ADEPT: Efficient Solar Energy Systems

    SciTech Connect (OSTI)

    2011-01-01

    Solar ADEPT Project: The 7 projects that make up ARPA-E's Solar ADEPT program, short for 'Solar Agile Delivery of Electrical Power Technology,' aim to improve the performance of photovoltaic (PV) solar energy systems, which convert the sun's rays into electricity. Solar ADEPT projects are integrating advanced electrical components into PV systems to make the process of converting solar energy to electricity more efficient.

  15. Hybrid Solar Lighting Provides Energy Savings and Reduces Waste Heat

    SciTech Connect (OSTI)

    Lapsa, Melissa Voss; Maxey, L Curt; Earl, Dennis Duncan; Beshears, David L; Ward, Christina D; Parks, James Edgar

    2006-01-01

    ABSTRACT Artificial lighting is the largest component of electricity use in commercial U.S. buildings. Hybrid solar lighting (HSL) provides an exciting new means of reducing energy consumption while also delivering significant ancillary benefits associated with natural lighting in buildings. As more than half of all federal facilities are in the Sunbelt region (defined as having an average direct solar radiation of greater than 4 kWh/m2/day) and as more than half of all square footage available in federal buildings is also in the Sunbelt, HSL is an excellent technology fit for federal facilities. The HSL technology uses a rooftop, 4-ft-wide dish and secondary mirror that track the sun throughout the day (Fig. 1). The collector system focuses the sunlight onto 127 optical fibers. The fibers serve as flexible light pipes and are connected to hybrid light fixtures that have special diffusion rods that spread out the light in all directions. One collector powers about eight hybrid light fixtures-which can illuminate about 1,000 square feet. The system tracks at 0.1 accuracy, required by the two-mirror geometry to keep the focused beam on the fiber bundle. When sunlight is plentiful, the optical fibers in the luminaires provide all or most of the light needed in an area. During times of little or no sunlight, a sensor controls the intensity of the artificial lamps to maintain a desired illumination level. Unlike conventional electric lamps, the natural light produces little to no waste heat and is cool to the touch. This is because the system's solar collector removes the infrared light-the part of the spectrum that generates a lot of the heat in conventional bulbs-from the sunlight.

  16. Concentrating Solar Power

    SciTech Connect (OSTI)

    Not Available

    2008-09-01

    Summarizes the goals and activities of the DOE Solar Energy Technologies Program efforts within its concentrating solar power subprogram.

  17. Solar Easements & Local Option Solar Rights Laws

    Broader source: Energy.gov [DOE]

    Utah's solar easement provision is similar to easement provisions in many other states. Parties may voluntarily enter into written solar easement contracts that are enforceable by law. An...

  18. Solar Energy Technologies Program: Concentrating Solar Power

    SciTech Connect (OSTI)

    2009-10-26

    Fact sheet summarizing the goals and activities of the DOE Solar Energy Technologies Program efforts within its concentrating solar power subprogram.

  19. Concentrating Solar Power Projects | Concentrating Solar Power...

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

    SolarPACES, an international program of the International Energy Agency, furthers collaborative development, testing, and marketing of concentrating solar power plants. Activities ...

  20. Central solar-energy receiver

    DOE Patents [OSTI]

    Not Available

    1981-10-27

    An improved tower-mounted central solar energy receiver for heating air drawn through the receiver by an induced draft fan is described. A number of vertically oriented, energy absorbing, fin-shaped slats are radially arranged in a number of concentric cylindrical arrays on top of the tower coaxially surrounding a pipe having air holes through which the fan draws air which is heated by the slats which receive the solar radiation from a heliostat field. A number of vertically oriented and wedge-shaped columns are radially arranged in a number of concentric cylindrical clusters surrounding the slat arrays. The columns have two mirror-reflecting sides to reflect radiation into the slat arrays and one energy absorbing side to reduce reradiation and reflection from the slat arrays.

  1. Current flow and potential efficiency of solar cells based on GaAs and GaSb p-n junctions

    SciTech Connect (OSTI)

    Andreev, V. M.; Evstropov, V. V.; Kalinovsky, V. S. Lantratov, V. M.; Khvostikov, V. P.

    2009-05-15

    Dependence of the efficiency of single-junction and multijunction solar cells on the mechanisms of current flow in photoactive p-n junctions, specifically on the form of the dark current-voltage characteristic J-V, has been studied. The resistanceless J-V{sub j} characteristic (with the series resistance disregarded) of a multijunction solar cell has the same shape as the characteristic of a single-junction cell: both feature a set of exponential portions. This made it possible to develop a unified analytical method for calculating the efficiency of singlejunction and multijunction solar cells. The equation relating the efficiency to the photogenerated current at each portion of the J-V{sub j} characteristic is derived. For p-n junctions in GaAs and GaSb, the following characteristics were measured: the dark J-V characteristic, the dependence of the open-circuit voltage on the illumination intensity P-V{sub OC}, and the dependence of the luminescence intensity on the forward current L-J. Calculated dependences of potential efficiency (under idealized condition for equality to unity of external quantum yield) on the photogenerated current for single-junction GaAs and GaSb solar cells and a GaAs/GaSb tandem are plotted. The form of these dependences corresponds to the shape of J-V{sub j} characteristics: there are the diffusion- and recombination-related portions; in some cases, the tunneling-trapping portion is also observed. At low degrees of concentration of solar radiation (C < 10), an appreciable contribution to photogenerated current is made by recombination component. It is an increase in this component in the case of irradiation with 6.78-MeV protons or 1-MeV electrons that brings about a decrease in the efficiency of conversion of unconcentrated solar radiation.

  2. National Solar Radiation Database | Open Energy Information

    Open Energy Info (EERE)

    Program Website4 Program Website5 References http:www.nrel.govnewspress2007516.html http:rredc.nrel.govsolarpubsNSRDBbackground.html http:...

  3. Apparatus and method for solar coal gasification

    DOE Patents [OSTI]

    Gregg, David W.

    1980-01-01

    Apparatus for using focused solar radiation to gasify coal and other carbonaceous materials. Incident solar radiation is focused from an array of heliostats onto a tower-mounted secondary mirror which redirects the focused solar radiation down through a window onto the surface of a vertically-moving bed of coal, or a fluidized bed of coal, contained within a gasification reactor. The reactor is designed to minimize contact between the window and solids in the reactor. Steam introduced into the gasification reactor reacts with the heated coal to produce gas consisting mainly of carbon monoxide and hydrogen, commonly called "synthesis gas", which can be converted to methane, methanol, gasoline, and other useful products. One of the novel features of the invention is the generation of process steam at the rear surface of the secondary mirror.

  4. Solar thermophotovoltaic system using nanostructures

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

    Ungaro, Craig; Gray, Stephen K.; Gupta, Mool C.

    2015-08-20

    This paper presents results on a highly efficient experimental solar thermophotovoltaic (STPV) system using simulated solar energy. An overall power conversion efficiency of 6.2% was recorded under solar simulation. This was matched with a thermodynamic model, and the losses within the system, as well as a path forward to mitigate these losses, have been investigated. The system consists of a planar, tungsten absorbing/emitting structure with an anti-reflection layer coated laser-microtextured absorbing surface and single-layer dielectric coated emitting surface. A GaSb PV cell was used to capture the emitted radiation and convert it into electrical energy. This simple structure is bothmoreeasy to fabricate and temperature stable, and contains no moving parts or heat exchange fluids.less

  5. Beta Radiation

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

    Beta Radiation 1. Beta radiation may travel meters in air and is moderately penetrating. 2. Beta radiation can penetrate human skin to the "germinal layer," where new skin cells ...

  6. Energy savings obtainable through passive solar techniques

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1980-01-01

    A passive solar energy system is one in which the thermal energy flow is by natural means, that is by radiation, conduction, or natural convection. The purpose of the paper is to provide a survey of passive solar heating experience, especially in the US. Design approaches are reviewed and examples shown. Misconceptions are discussed. Advantages are listed. The Los Alamos program of performance simulation and evaluation is described and a simplified method of performance estimation is outlined.

  7. Studying the Solar System's Chemical Recipe

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

    Studying the Solar System's Chemical Recipe Print To study the origins of different isotope ratios among the elements that make up today's smorgasbord of planets, moons, comets, asteroids, and interplanetary ice and dust, a team of scientists from the University of California, San Diego is using ALS Chemical Dynamics Beamline 9.0.2 to mimic radiation from the protosun when the solar system was forming. For more than three decades, Mark Thiemens, Dean of the Division of Physical Sciences at UCSD,

  8. Studying the Solar System's Chemical Recipe

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

    Studying the Solar System's Chemical Recipe Print To study the origins of different isotope ratios among the elements that make up today's smorgasbord of planets, moons, comets, asteroids, and interplanetary ice and dust, a team of scientists from the University of California, San Diego is using ALS Chemical Dynamics Beamline 9.0.2 to mimic radiation from the protosun when the solar system was forming. For more than three decades, Mark Thiemens, Dean of the Division of Physical Sciences at UCSD,

  9. Studying the Solar System's Chemical Recipe

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

    Studying the Solar System's Chemical Recipe Print To study the origins of different isotope ratios among the elements that make up today's smorgasbord of planets, moons, comets, asteroids, and interplanetary ice and dust, a team of scientists from the University of California, San Diego is using ALS Chemical Dynamics Beamline 9.0.2 to mimic radiation from the protosun when the solar system was forming. For more than three decades, Mark Thiemens, Dean of the Division of Physical Sciences at UCSD,

  10. Studying the Solar System's Chemical Recipe

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

    Studying the Solar System's Chemical Recipe Print To study the origins of different isotope ratios among the elements that make up today's smorgasbord of planets, moons, comets, asteroids, and interplanetary ice and dust, a team of scientists from the University of California, San Diego is using ALS Chemical Dynamics Beamline 9.0.2 to mimic radiation from the protosun when the solar system was forming. For more than three decades, Mark Thiemens, Dean of the Division of Physical Sciences at UCSD,

  11. Current and lattice matched tandem solar cell

    DOE Patents [OSTI]

    Olson, Jerry M.

    1987-01-01

    A multijunction (cascade) tandem photovoltaic solar cell device is fabricated of a Ga.sub.x In.sub.1-x P (0.505.ltoreq.X.ltoreq.0.515) top cell semiconductor lattice matched to a GaAs bottom cell semiconductor at a low-resistance heterojunction, preferably a p+/n+ heterojunction between the cells. The top and bottom cells are both lattice matched and current matched for high efficiency solar radiation conversion to electrical energy.

  12. Toward the Development of Multi-Year Total and Special Solar...

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

    of Multi-Year Total and Special Solar Radiation Budgets at the Three ARM Locales Z. Li ... has been collected at Atmospheric Radiation Measurement (ARM) locales around the globe. ...

  13. AV Solar Ranch I Solar Power Plant | Open Energy Information

    Open Energy Info (EERE)

    AV Solar Ranch I Solar Power Plant Jump to: navigation, search Name AV Solar Ranch I Solar Power Plant Facility AV Solar Ranch I Sector Solar Facility Type Photovoltaic Developer...

  14. Foaming of aluminium-silicon alloy using concentrated solar energy

    SciTech Connect (OSTI)

    Cambronero, L.E.G.; Ruiz-Roman, J.M.; Canadas, I.; Martinez, D.

    2010-06-15

    Solar energy is used for the work reported here as a nonconventional heating system to produce aluminium foam from Al-Si alloy precursors produced by powder metallurgy. A commercial precursor in cylindrical bars enclosed in a stainless-steel mould was heated under concentrated solar radiation in a solar furnace with varied heating conditions (heating rate, time, and temperature). Concentrated solar energy close to 300 W/cm{sup 2} on the mould is high enough to achieve complete foaming after heating for only 200 s. Under these conditions, the density and pore distribution in the foam change depending on the solar heating parameters and mould design. (author)

  15. Solar Eclipse Monitoring for Solar Energy Applications Using the Solar and Moon Position Algorithms

    SciTech Connect (OSTI)

    Reda, I.

    2010-03-01

    This report includes a procedure for implementing an algorithm (described by Jean Meeus) to calculate the moon's zenith angle with uncertainty of +/-0.001 degrees and azimuth angle with uncertainty of +/-0.003 degrees. The step-by-step format presented here simplifies the complicated steps Meeus describes to calculate the Moon's position, and focuses on the Moon instead of the planets and stars. It also introduces some changes to accommodate for solar radiation applications.

  16. Solar energy thermalization and storage device

    DOE Patents [OSTI]

    McClelland, J.F.

    A passive solar thermalization and thermal energy storage assembly which is visually transparent is described. The assembly consists of two substantial parallel, transparent wall members mounted in a rectangular support frame to form a liquid-tight chamber. A semitransparent thermalization plate is located in the chamber, substantially paralled to and about equidistant from the transparent wall members to thermalize solar radiation which is stored in a transparent thermal energy storage liquid which fills the chamber. A number of the devices, as modules, can be stacked together to construct a visually transparent, thermal storage wall for passive solar-heated buildings.

  17. SERI QC Solar Data Quality Assessment Software

    Energy Science and Technology Software Center (OSTI)

    1994-12-31

    SERI QC is a mathematical software package that assesses the quality of solar radiation data. The SERI QC software is a function written in the C programming language. IT IS NOT A STANDALONE SOFTWARE APPLICATION. The user must write the calling application that requires quality assessment of solar data. The C function returns data quality flags to the calling program. A companion program, QCFIT, is a standalone Windows application that provides support files for themore » SERI QC function (data quality boundaries). The QCFIT software can also be used as an analytical tool for visualizing solar data quality independent of the SERI QC function.« less

  18. Solar energy thermalization and storage device

    DOE Patents [OSTI]

    McClelland, John F.

    1981-09-01

    A passive solar thermalization and thermal energy storage assembly which is visually transparent. The assembly consists of two substantial parallel, transparent wall members mounted in a rectangular support frame to form a liquid-tight chamber. A semitransparent thermalization plate is located in the chamber, substantially paralled to and about equidistant from the transparent wall members to thermalize solar radiation which is stored in a transparent thermal energy storage liquid which fills the chamber. A number of the devices, as modules, can be stacked together to construct a visually transparent, thermal storage wall for passive solar-heated buildings.

  19. Orlando, Florida: Solar in Action (Brochure), Solar America Cities...

    Office of Environmental Management (EM)

    Orlando, Florida: Solar in Action (Brochure), Solar America Cities, Energy Efficiency & Renewable Energy (EERE) Orlando, Florida: Solar in Action (Brochure), Solar America Cities,...

  20. Denver, Colorado: Solar in Action (Brochure), Solar America Cities...

    Office of Environmental Management (EM)

    Denver, Colorado: Solar in Action (Brochure), Solar America Cities, Energy Efficiency & Renewable Energy (EERE) Denver, Colorado: Solar in Action (Brochure), Solar America Cities,...

  1. Kings River Conservation District (KRCD) Solar Farm Solar Power...

    Open Energy Info (EERE)

    River Conservation District (KRCD) Solar Farm Solar Power Plant Jump to: navigation, search Name Kings River Conservation District (KRCD) Solar Farm Solar Power Plant Facility...

  2. Space Coast Next Generation Solar Energy Center Solar Power Plant...

    Open Energy Info (EERE)

    Coast Next Generation Solar Energy Center Solar Power Plant Jump to: navigation, search Name Space Coast Next Generation Solar Energy Center Solar Power Plant Facility Space Coast...

  3. Martin Next Generation Solar Energy Center Solar Power Plant...

    Open Energy Info (EERE)

    Next Generation Solar Energy Center Solar Power Plant Jump to: navigation, search Name Martin Next Generation Solar Energy Center Solar Power Plant Facility Martin Next Generation...

  4. Portland, Oregon: Solar in Action (Brochure), Solar America Cities...

    Office of Environmental Management (EM)

    Portland, Oregon: Solar in Action (Brochure), Solar America Cities, Energy Efficiency & Renewable Energy (EERE) Portland, Oregon: Solar in Action (Brochure), Solar America Cities, ...

  5. EE Solar Energy Efficiency Solar | Open Energy Information

    Open Energy Info (EERE)

    EE Solar Energy Efficiency Solar Jump to: navigation, search Name: EE Solar (Energy Efficiency Solar) Place: Ponoma, California Zip: 91768 Product: PV systems installer based in...

  6. Willard Kelsey Solar Group WK Solar | Open Energy Information

    Open Energy Info (EERE)

    Willard Kelsey Solar Group WK Solar Jump to: navigation, search Name: Willard & Kelsey Solar Group (WK Solar) Place: Perrysburg, Ohio Zip: 43551 Product: Manufacturer of CdTe...

  7. Innotech Solar AS formerly known as Solar Cell Repower | Open...

    Open Energy Info (EERE)

    Innotech Solar AS formerly known as Solar Cell Repower Jump to: navigation, search Name: Innotech Solar AS (formerly known as Solar Cell Repower) Place: Narvik, Norway Zip: 8512...

  8. Wuxi Jiacheng Solar Energy Technology Co JC Solar | Open Energy...

    Open Energy Info (EERE)

    JC Solar Jump to: navigation, search Name: Wuxi Jiacheng Solar Energy Technology Co (JC Solar) Place: Yixing, Jiangsu Province, China Zip: 214200 Sector: Solar Product: A Chinese...

  9. Innovative Systems Engineering Solar LLC ISE Solar LLC | Open...

    Open Energy Info (EERE)

    Systems Engineering Solar LLC ISE Solar LLC Jump to: navigation, search Name: Innovative Systems Engineering Solar LLC (ISE Solar LLC) Place: Warminster, Pennsylvania Zip:...

  10. First Solar Electric LLC formerly DT Solar | Open Energy Information

    Open Energy Info (EERE)

    Electric LLC formerly DT Solar Jump to: navigation, search Name: First Solar Electric LLC (formerly DT Solar) Place: Branchburg, New Jersey Zip: 8876 Sector: Solar Product: PV...

  11. Aide Solar Jiangsu Aide Solar Energy Technology Co Ltd | Open...

    Open Energy Info (EERE)

    Aide Solar Jiangsu Aide Solar Energy Technology Co Ltd Jump to: navigation, search Name: Aide Solar (Jiangsu Aide Solar Energy Technology Co Ltd) Place: Xuzhou, Jiangsu Province,...

  12. AET Solar formerly solar division of GGAM Electrical Services...

    Open Energy Info (EERE)

    Solar formerly solar division of GGAM Electrical Services Jump to: navigation, search Name: AET Solar (formerly solar division of GGAM Electrical Services) Place: Limassol, Cyprus...

  13. Creative Energy Solar Investments SA formerly Hellenic Solar...

    Open Energy Info (EERE)

    Solar Investments SA formerly Hellenic Solar Jump to: navigation, search Name: Creative Energy Solar Investments SA (formerly Hellenic Solar) Place: 18538 Piraeus, Greece Product:...

  14. China Glass Solar aka CG Solar formerly Weihai Bluestar Terra...

    Open Energy Info (EERE)

    Glass Solar aka CG Solar formerly Weihai Bluestar Terra Photovoltaic Co Ltd Jump to: navigation, search Name: China Glass Solar (aka CG Solar, formerly Weihai Bluestar Terra...

  15. Siemens Solar formerly ARCO Solar Corporation | Open Energy Informatio...

    Open Energy Info (EERE)

    Solar formerly ARCO Solar Corporation Jump to: navigation, search Name: Siemens Solar (formerly ARCO Solar Corporation) Place: Arizona Product: Built a 6MW CPV project in 1984,...

  16. Siemens Concentrated Solar Power Ltd previously Solel Solar Systems...

    Open Energy Info (EERE)

    Siemens Concentrated Solar Power Ltd previously Solel Solar Systems Jump to: navigation, search Name: Siemens Concentrated Solar Power Ltd (previously Solel Solar Systems) Place:...

  17. Guodian Jintech Solar Energy formerly Yixing Jintech Solar Energy...

    Open Energy Info (EERE)

    Jintech Solar Energy formerly Yixing Jintech Solar Energy Co Ltd Jump to: navigation, search Name: Guodian Jintech Solar Energy (formerly Yixing Jintech Solar Energy Co Ltd) Place:...

  18. Shanghai Comtec Solar Technology Ltd aka Comtec Solar System...

    Open Energy Info (EERE)

    Comtec Solar Technology Ltd aka Comtec Solar System Group Ltd Jump to: navigation, search Name: Shanghai Comtec Solar Technology Ltd (aka Comtec Solar System Group Ltd) Place:...

  19. Ecosystem Solar Electric Corp aka Solar MW Energy Inc | Open...

    Open Energy Info (EERE)

    Solar Electric Corp aka Solar MW Energy Inc Jump to: navigation, search Name: Ecosystem Solar Electric Corp, aka Solar MW Energy Inc Place: Ontario, California Zip: 91761 Product:...

  20. ET Solar Group Formerly CNS Solar Industry | Open Energy Information

    Open Energy Info (EERE)

    Solar Group Formerly CNS Solar Industry Jump to: navigation, search Name: ET Solar Group (Formerly CNS Solar Industry) Place: Nanjing, Jiangsu Province, China Zip: 210009 Sector:...

  1. Entech Solar Inc formerly WorldWater Solar Technologies | Open...

    Open Energy Info (EERE)

    Solar Inc formerly WorldWater Solar Technologies Jump to: navigation, search Name: Entech Solar Inc. (formerly WorldWater & Solar Technologies) Place: Fort Worth, Texas Zip: 76177...

  2. Milwaukee, Wisconsin: Solar in Action (Brochure), Solar America...

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

    Milwaukee, Wisconsin: Solar in Action (Brochure), Solar America Cities, Energy Efficiency & Renewable Energy (EERE) Milwaukee, Wisconsin: Solar in Action (Brochure), Solar America ...

  3. Houston, Texas: Solar in Action (Brochure), Solar America Cities...

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

    Houston, Texas: Solar in Action (Brochure), Solar America Cities, Energy Efficiency & Renewable Energy (EERE) Houston, Texas: Solar in Action (Brochure), Solar America Cities, ...

  4. edition Not Available 14 SOLAR ENERGY; SOLAR ENERGY; EDUCATIONAL...

    Office of Scientific and Technical Information (OSTI)

    Home economics: student activities. Field test edition Not Available 14 SOLAR ENERGY; SOLAR ENERGY; EDUCATIONAL TOOLS; CURRICULUM GUIDES; GLAZING; HOUSES; SOLAR COOKERS; SOLAR...

  5. Solar Utility Networks: Replicable Innovations in Solar Energy...

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

    Solar Utility Networks: Replicable Innovations in Solar Energy (SUNRISE) Funding Opportunity Solar Utility Networks: Replicable Innovations in Solar Energy (SUNRISE) Funding ...

  6. PROJECT PROFILE: The Solar Foundation - Solar Training Network...

    Energy Savers [EERE]

    Training Network PROJECT PROFILE: The Solar Foundation - Solar Training Network Project Name: Solar Training Network Funding Opportunity: Solar Training and Education for ...

  7. Seattle, Washington: Solar in Action (Brochure), Solar America...

    Energy Savers [EERE]

    Seattle, Washington: Solar in Action (Brochure), Solar America Cities, Energy Efficiency & Renewable Energy (EERE) Seattle, Washington: Solar in Action (Brochure), Solar America ...

  8. EIS-0449: Solar Millennium Blythe Solar Power Project in Riverside...

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

    9: Solar Millennium Blythe Solar Power Project in Riverside County, CA EIS-0449: Solar Millennium Blythe Solar Power Project in Riverside County, CA December 10, 2010 EIS-0449: ...

  9. Early solar mass loss, opacity uncertainties, and the solar abundance...

    Office of Scientific and Technical Information (OSTI)

    Early solar mass loss, opacity uncertainties, and the solar abundance problem Citation Details In-Document Search Title: Early solar mass loss, opacity uncertainties, and the solar ...

  10. EA-1798: Abengoa Solar's Mojave Solar Project near Barstow, CA...

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

    8: Abengoa Solar's Mojave Solar Project near Barstow, CA EA-1798: Abengoa Solar's Mojave Solar Project near Barstow, CA July 1, 2011 EA-1798: Final Environmental Assessment Loan ...

  11. San Antonio, Texas: Solar in Action (Brochure), Solar America...

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

    Antonio, Texas: Solar in Action (Brochure), Solar America Cities, Energy Efficiency & Renewable Energy (EERE) San Antonio, Texas: Solar in Action (Brochure), Solar America Cities, ...

  12. Solar Impulse's Solar-Powered Plane

    ScienceCinema (OSTI)

    Moniz, Ernest; Piccard, Bertrand; Reicher, Dan

    2014-01-07

    Solar Impulse lands in Washington, DC at Washington Dulles International Airport as part of its journey across the United States. Secretary Ernest Moniz speaks about how advancements like those at the Department of Energy are leading the way for innovations like the solar-powered plane. Footage of the solar-powered plane courtesy of Solar Impulse.

  13. Solar Impulse's Solar-Powered Plane

    SciTech Connect (OSTI)

    Moniz, Ernest; Piccard, Bertrand; Reicher, Dan

    2013-07-08

    Solar Impulse lands in Washington, DC at Washington Dulles International Airport as part of its journey across the United States. Secretary Ernest Moniz speaks about how advancements like those at the Department of Energy are leading the way for innovations like the solar-powered plane. Footage of the solar-powered plane courtesy of Solar Impulse.

  14. Stellate solar collector

    SciTech Connect (OSTI)

    Womack, R. R.

    1981-02-03

    A solar collector device of the type adapted for heating water and the like is disclosed. An elongated, opaque collector is provided with a plurality of radially extending vanes so as to define a hollow interior of stellate cross-section. Water is sprayed through a feeding conduit which extends through the hollow interior. As the sprayed water accumulates upon the interior vane surfaces, the collector wheel is rotated according to the weight of the deposited water. As the vane tips are rotated downwardly, the water is heated by conductive contact with the interior vane surfaces and by convection and radiation within the hollow interior. The heated water is then discharged downwardly through apertures in the vane tips into a collector pan. The invention is distinguished from the prior art in its introduction of the water upon the interior surfaces of collector vanes within a paddle wheel of stellate configuration, rather than upon the exterior surfaces of the vanes. The stellate configuration provides an increased area of exposure to the radiation of the sun within a compact unit and provides heating of the water by conduction, convection and radiation.

  15. Concentrating Solar Power Projects | Department of Energy

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

    Concentrating Solar Power Projects Concentrating Solar Power Projects Concentrating Solar Power Projects Concentrating Solar Power Projects Concentrating Solar Power Projects Concentrating Solar Power Projects Concentrating Solar Power Projects Concentrating Solar Power Projects Concentrating Solar Power Projects Concentrating Solar Power Projects Concentrating Solar Power Projects Concentrating Solar Power Projects Concentrating Solar Power Projects Concentrating Solar Power Projects

  16. Solar engineering 1991

    SciTech Connect (OSTI)

    Mancini, T.R. ); Watanabe, K. ); Klett, D.E. )

    1991-01-01

    This book contains paper presented at the second ASME-JSES-JSME international solar energy conference. It is organized under the following headings: Solar ponds, Energy fundamentals in solar systems, General solar energy, Solar powered cars, Distributed receiver components and systems, Central receiver components and systems, Chemical processes and waste destruction, High flux and innovative applications, Solar thermal space propulsion, Solar dynamic power systems, Analysis methods for monitored building use. Photovoltaics, Testing and measurement.

  17. Zero Carryover Liquid-Desiccant Air Conditioner for Solar Applications...

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

    ... less expensive, but they supply thermal energy at a lower temperature: ... they will deliver between 50% and 60% of the incident solar radiation as hot water at 180F (82C). ...

  18. Solar collector

    SciTech Connect (OSTI)

    Wilhelm, W.G.

    1982-05-04

    The field of this invention is solar collectors, and more particularly, the invention pertains to a flat plate collector that employs high performance thin films. The solar collector of this invention overcomes several problems in this field, such as excessive hardware, cost and reliability, and other prior art drawbacks outlined in the specification. In the preferred form, the apparatus features a substantially rigid planar frame. A thin film window is bonded to one planar side of the frame. An absorber of laminate construction is comprised of two thin film layers that are sealed perimetrically. The layers define a fluid-tight planar envelope of large surface area to volume through which a heat transfer fluid flows. Absorber is bonded to the other planar side of the frame. The thin film construction of the absorber assures substantially full envelope wetting and thus good efficiency. The window and absorber films stress the frame adding to the overall strength of the collector.

  19. Shell Solar | Open Energy Information

    Open Energy Info (EERE)

    Solar Jump to: navigation, search Name: Shell Solar Place: The Hague, Netherlands Zip: 2501 AN Sector: Solar Product: Shell Solar is developing non-crystalline PV technology,...

  20. Apex Solar | Open Energy Information

    Open Energy Info (EERE)

    Name: Apex Solar Place: Sofia, Bulgaria Zip: 1616 Sector: Solar Product: Bulgarian PV and solar thermal project developer and installer. References: Apex Solar1 This article is a...

  1. Atlantic Solar | Open Energy Information

    Open Energy Info (EERE)

    navigation, search Logo: Atlantic Solar Name: Atlantic Solar Place: Cape Town, South Africa Sector: Solar Product: Solar Thermal Technology Year Founded: 1985 Phone Number:...

  2. Declination Solar | Open Energy Information

    Open Energy Info (EERE)

    San Francisco, California Sector: Solar Product: San Francisco solar installation firm acquired by SolarCity in September 2006. References: Declination Solar1 This article...

  3. Solar Energy | Department of Energy

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

    Energy Resource Library Solar Energy Solar Energy Below are resources for Tribes on solar energy technologies. A Guide to Community Solar: Utility, Private, and Nonprofit ...

  4. Corona Solar | Open Energy Information

    Open Energy Info (EERE)

    Solar Jump to: navigation, search Name: Corona Solar Place: Tholey-Theley, Germany Zip: D 66636 Sector: Solar Product: Engaged in solar passive large-size collectors. References:...

  5. AS Solar | Open Energy Information

    Open Energy Info (EERE)

    Solar Jump to: navigation, search Name: AS Solar Address: Am Tnniesberg 4A Place: Hannover, Germany Sector: Solar Product: PV, solar thermal Phone Number: +49 511 475578 - 0...

  6. Abengoa Solar | Open Energy Information

    Open Energy Info (EERE)

    Solar Jump to: navigation, search Logo: Abengoa Solar Name: Abengoa Solar Address: 11500 W 13th Ave Place: Lakewood, Colorado Zip: 80215 Region: Rockies Area Sector: Solar Product:...

  7. First Solar | Open Energy Information

    Open Energy Info (EERE)

    First Solar Name: First Solar Address: 350 West Washington Street, Suite 600 Place: Tempe, Arizona Zip: 85281 Sector: Solar Product: Solar energy systems Year Founded: 1999 Phone...

  8. Solar Systems | Open Energy Information

    Open Energy Info (EERE)

    Logo: Solar Systems Name: Solar Systems Address: 45 Grosvenor Street Place: Abbotsford, Australia Sector: Solar Product: Solar concentrators Phone Number: +61 3 9413 8000 Website:...

  9. Ascent Solar | Open Energy Information

    Open Energy Info (EERE)

    Solar Jump to: navigation, search Logo: Ascent Solar Name: Ascent Solar Address: 12300 Grant Street Place: Thornton, Colorado Zip: 80241 Region: Rockies Area Sector: Solar Product:...

  10. Borrego Solar | Open Energy Information

    Open Energy Info (EERE)

    Borrego Solar Jump to: navigation, search Logo: Borrego Solar Name: Borrego Solar Address: 2560 9th Street Place: Berkeley, California Zip: 94710 Region: Bay Area Sector: Solar...

  11. DPW Solar | Open Energy Information

    Open Energy Info (EERE)

    DPW Solar Jump to: navigation, search Logo: DPW Solar Name: DPW Solar Address: 4000 B Vassar Dr. NE Place: Albuquerque, New Mexico Zip: 87107 Sector: Solar Product: Renewable...

  12. Inovateus Solar | Open Energy Information

    Open Energy Info (EERE)

    Inovateus Solar Jump to: navigation, search Logo: Inovateus Solar Name: Inovateus Solar Address: 19890 State Line Rd. Place: South Bend, Indiana Zip: 46637 Sector: Solar Product:...

  13. Standard Solar | Open Energy Information

    Open Energy Info (EERE)

    Standard Solar Name: Standard Solar Address: 202 Perry Parkway Place: Gaithersburg, Maryland Zip: 20877 Region: Northeast - NY NJ CT PA Area Sector: Solar Product: Solar...

  14. Wasatch Solar | Open Energy Information

    Open Energy Info (EERE)

    Solar Jump to: navigation, search Name: Wasatch Solar Address: 4417 S 2950 E Place: Salt Lake City, Utah Zip: 84124 Sector: Solar Product: Solar Year Founded: 2009 Phone...

  15. Sylcom Solar | Open Energy Information

    Open Energy Info (EERE)

    Sylcom Solar provides the design, research, distribution, construction, operation, maintenance of products and of Photovoltaic Solar, Thermal Solar and Solar Thermoelectric...

  16. Genesis Solar | Open Energy Information

    Open Energy Info (EERE)

    Genesis Solar Facility Genesis Solar Sector Solar Facility Type Concentrating solar power Facility Status Under Construction Owner NextEra Developer NextEra Location Blythe,...

  17. Solar Easements | Department of Energy

    Office of Environmental Management (EM)

    Process Heat Solar Photovoltaics Daylighting Solar Pool Heating Program Info Sector Name State State Kentucky Program Type SolarWind Access Policy Summary In Kentucky, solar ...

  18. Preussen Solar | Open Energy Information

    Open Energy Info (EERE)

    Preussen Solar Jump to: navigation, search Name: Preussen Solar Place: Berlin, Germany Zip: 10711 Sector: Solar Product: Involved in solar projects. Coordinates: 52.516074,...

  19. Scaled Solar | Open Energy Information

    Open Energy Info (EERE)

    Solar Product: Scaled Solar manufacturers and markets utility-grade, concentrated photovoltaic solar energy systems to commercial customers References: Scaled Solar1 This...

  20. Solar PST | Open Energy Information

    Open Energy Info (EERE)

    search Name: Solar PST Place: Bergondo, Spain Zip: 15 165 Sector: Solar Product: Spanish company producing thermodynamic solar panels. References: Solar PST1 This article...

  1. Immodo Solar | Open Energy Information

    Open Energy Info (EERE)

    Jump to: navigation, search Name: Immodo Solar Place: Spain Sector: Solar Product: Spanish company which installs and maintains solar panels. References: Immodo Solar1 This...

  2. Solarize Guidebook | Department of Energy

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

    Solarize Guidebook Solarize Guidebook This guidebook is intended to be a roadmap for project planners and solar advocates who want to create their own successful Solarize ...

  3. Solar Energy

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

    Energy - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense Waste Management Programs Advanced Nuclear Energy

  4. Solar cogeneration

    SciTech Connect (OSTI)

    Not Available

    1982-04-01

    After a brief introduction to the operational principles and advantages of solar cogeneration, seven cogeneration studies are summarized covering such applications as sulfur mining, copper smelting, enhanced oil recovery, natural gas processing, sugar mill operations, and space heating and cooling. For each plant is given a brief site description, project summary, conceptual design, and functional description, including a picture of the facility and a flow chart. Also listed are the addresses of the companies involved for obtaining additional information. (LEW)

  5. Solar Newsletter

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

    2 - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense Waste Management Programs Advanced Nuclear Energy Nuclear

  6. Government research and development summaries: Solar Project Briefs. Irregular

    SciTech Connect (OSTI)

    Not Available

    1991-01-01

    Solar Project Briefs describe the status of all R D programs submitted to the Power Information Center by the government sponsors in solar radiation collection, storage, and conversion to heat or other energy forms. Photovoltaic and solar thermal devices and related systems are also reported. The document is not to be reproducted, in whole or in part, for dissemination outside your own organization nor may it be reproduced for advertising or sales promotion purposes.

  7. An Improved Daylight Correction for IR Loss in ARM Diffuse SW Measurements

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

    An Improved Daylight Correction for IR Loss in ARM Diffuse SW Measurements C. N. Long, K. Younkin, and K. L. Gaustad Pacific Northwest National Laboratory Richland, Washington J. A. Augustine National Oceanic and Atmospheric Administration Air Resources Laboratory Surface Radiation Research Branch Boulder, Colorado Introduction A paper by Cess et al. (2000) notes that some clear-sky diffuse shortwave (SW) measurements they were using from the Atmospheric Radiation Measurement (ARM) Southern

  8. Solar Contractor Licensing | Department of Energy

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

    < Back Eligibility InstallersContractors Savings Category Solar - Passive Solar Water Heat Solar Space Heat Solar Thermal Electric Solar Thermal Process Heat Solar Photovoltaics...

  9. Laser activated diffuse discharge switch (Patent) | DOEPatents

    Office of Scientific and Technical Information (OSTI)

    Laser activated diffuse discharge switch Title: Laser activated diffuse discharge switch The invention is a gas mixture for a diffuse discharge switch which is capable of changing ...

  10. Solar energy collector

    DOE Patents [OSTI]

    Brin, Raymond L.; Pace, Thomas L.

    1978-01-01

    The invention relates to a solar energy collector comprising solar energy absorbing material within chamber having a transparent wall, solar energy being transmitted through the transparent wall, and efficiently absorbed by the absorbing material, for transfer to a heat transfer fluid. The solar energy absorbing material, of generally foraminous nature, absorbs and transmits the solar energy with improved efficiency.

  11. Solar Innovator | Alta Devices

    ScienceCinema (OSTI)

    Mattos, Laila; Le, Minh

    2013-05-29

    Selected to participate in the Energy Department's SunShot Initiative, Alta Devices produces solar cells that convert sunlight into electricity at world record-breaking levels of efficiency. Through its innovative solar technology Alta is helping bring down the cost of solar. Learn more about the Energy Department's efforts to advance solar technology at energy.gov/solar .

  12. Selective radiative cooling with MgO and/or LiF layers

    SciTech Connect (OSTI)

    Berdahl, P.H.

    1984-09-14

    A selective radiation cooling material which is absorptive only in the 8 to 13 microns wavelength range is accomplished by placing ceramic magnesium oxide and/or polycrystalline lithium fluoride on an infrared-reflective substrate. The reflecting substrate may be a metallic coating, foil or sheet, such as aluminum, which reflects all atmospheric radiation from 0.3 to 8 microns, the magnesium oxide and lithium fluoride being nonabsorptive at those wavelengths. <10% of submicron voids in the material is permissible in which case the MgO and/or LiF layer is diffusely scattering, but still nonabsorbing, in the wavelength range of 0.3 to 8 microns. At wavelengths from 8 to 13 microns, the magnesium oxide and lithium fluoride radiate power through the ''window'' in the atmosphere, and thus remove heat from the reflecting sheet of material and the attached object to be cooled. At wavelengths longer than 13 microns, the magnesium oxide and lithium fluoride reflects the atmospheric radiation back into the atmosphere. This high reflectance is only obtained if the surface is sufficiently smooth: roughness on a scale of 1 micron is permissible but roughness on a scale of 10 microns is not. An infrared-transmitting cover or shield is mounted in spaced relationship to the material to reduce convective heat transfer. If this is utilized in direct sunlight, the infrared transmitting cover or shield should be opaque in the solar spectrum of 0.3 to 3 microns.

  13. Improved solar heating systems

    DOE Patents [OSTI]

    Schreyer, J.M.; Dorsey, G.F.

    1980-05-16

    An improved solar heating system is described in which the incident radiation of the sun is absorbed on collector panels, transferred to a storage unit and then distributed as heat for a building and the like. The improvement is obtained by utilizing a storage unit comprising separate compartments containing an array of materials having different melting points ranging from 75 to 180/sup 0/F. The materials in the storage system are melted in accordance with the amount of heat absorbed from the sun and then transferred to the storage system. An efficient low volume storage system is provided by utilizing the latent heat of fusion of the materials as they change states in storing ad releasing heat for distribution.

  14. Solar heating system

    DOE Patents [OSTI]

    Schreyer, James M.; Dorsey, George F.

    1982-01-01

    An improved solar heating system in which the incident radiation of the sun is absorbed on collector panels, transferred to a storage unit and then distributed as heat for a building and the like. The improvement is obtained by utilizing a storage unit comprising separate compartments containing an array of materials having different melting points ranging from 75.degree. to 180.degree. F. The materials in the storage system are melted in accordance with the amount of heat absorbed from the sun and then transferred to the storage system. An efficient low volume storage system is provided by utilizing the latent heat of fusion of the materials as they change states in storing and releasing heat for distribution.

  15. Concentrating Solar Power Projects - Nevada Solar One | Concentrating Solar

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

    Power | NREL Nevada Solar One This page provides information on Nevada Solar One, a concentrating solar power (CSP) project, with data organized by background, participants, and power plant configuration. Acciona Energy's Nevada Solar One is the third largest CSP plant in the world and the first plant built in the United States since 1999. Located in Boulder City, Nevada, about 40 miles southeast of Las Vegas, this parabolic trough system has been operating since June 2007. The US$260

  16. Internal absorber solar collector

    DOE Patents [OSTI]

    Sletten, Carlyle J.; Herskovitz, Sheldon B.; Holt, F. S.; Sletten, E. J.

    1981-01-01

    Thin solar collecting panels are described made from arrays of small rod collectors consisting of a refracting dielectric rod lens with an absorber imbedded within it and a reflecting mirror coated on the back side of the dielectric rod. Non-tracking collector panels on vertical walls or roof tops receive approximately 90% of solar radiation within an acceptance zone 60.degree. in elevation angle by 120.degree. or more in the azimuth sectors with a collector concentration ratio of approximately 3.0. Miniaturized construction of the circular dielectric rods with internal absorbers reduces the weight per area of glass, plastic and metal used in the collector panels. No external parts or insulation are needed as heat losses are low due to partial vacuum or low conductivity gas surrounding heated portions of the collector. The miniature internal absorbers are generally made of solid copper with black selective surface and the collected solar heat is extracted at the collector ends by thermal conductivity along the absorber rods. Heat is removed from end fittings by use of liquid circulants. Several alternate constructions are provided for simplifying collector panel fabrication and for preventing the thermal expansion and contraction of the heated absorber or circulant tubes from damaging vacuum seals. In a modified version of the internal absorber collector, oil with temperature dependent viscosity is pumped through a segmented absorber which is now composed of closely spaced insulated metal tubes. In this way the circulant is automatically diverted through heated portions of the absorber giving higher collector concentration ratios than theoretically possible for an unsegmented absorber.

  17. SOLAR NANTENNA ELECTROMAGNETIC COLLECTORS

    SciTech Connect (OSTI)

    Steven D. Novack; Dale K. Kotter; Dennis Slafer; Patrick Pinhero

    2008-08-01

    This research explores a new efficient approach for producing electricity from the abundant energy of the sun. A nanoantenna electromagnetic collector (NEC) has been designed, prototyped, and tested. Proof of concept has been validated. The device targets mid-infrared wavelengths where conventional photovoltaic (PV) solar cells do not respond but is abundant in solar energy. The initial concept of designing NEC antennas was based on scaling of radio frequency antenna theory. This approach has proven unsuccessful by many due to not fully understanding and accounting for the optical behavior of materials in the THz region. Also until recent years the nanofabrication methods were not available to fabricate the optical antenna elements. We have addressed and overcome both technology barriers. Several factors were critical in successful implementation of NEC including: 1) frequency-dependent modeling of antenna elements, 2) selection of materials with proper THz properties and 3) novel manufacturing methods that enable economical large-scale manufacturing. The work represents an important step toward the ultimate realization of a low-cost device that will collect as well as convert this radiation into electricity, which will lead to a wide spectrum, high conversion efficiency, and low cost solution to complement conventional PVs.

  18. Copper Mountain Solar Farm

    Broader source: Energy.gov [DOE]

    This b-roll shows a large-scale solar farm in Nevada that generates renewable solar energy using parabolic troughs, a form of concentrating solar power (CSP) technology, and photovoltaic technology.

  19. Smart Solar Marketing Strategies

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

    ... e Cost. Consumers report high up-front and out-of-pocket costs and long payback periods deter them from installing solar ... While state solar pro- grams do not produce solar panels, ...

  20. Solar Neutrino Problem

    DOE R&D Accomplishments [OSTI]

    Davis, R. Jr.; Evans, J. C.; Cleveland, B. T.

    1978-04-28

    A summary of the results of the Brookhaven solar neutrino experiment is given and discussed in relation to solar model calculations. A review is given of the merits of various new solar neutrino detectors that were proposed.

  1. Solar Easements & Rights Laws

    Office of Energy Efficiency and Renewable Energy (EERE)

    The Solar Recordation Act describes the procedures for filing a solar right through the County Clerk's Office. The property owner seeking the solar right must give advanced notice to the adjacent...

  2. Diffusion in silicon isotope heterostructures

    SciTech Connect (OSTI)

    Silvestri, Hughes Howland

    2004-05-14

    The simultaneous diffusion of Si and the dopants B, P, and As has been studied by the use of a multilayer structure of isotopically enriched Si. This structure, consisting of 5 pairs of 120 nm thick natural Si and {sup 28}Si enriched layers, enables the observation of {sup 30}Si self-diffusion from the natural layers into the {sup 28}Si enriched layers, as well as dopant diffusion from an implanted source in an amorphous Si cap layer, via Secondary Ion Mass Spectrometry (SIMS). The dopant diffusion created regions of the multilayer structure that were extrinsic at the diffusion temperatures. In these regions, the Fermi level shift due to the extrinsic condition altered the concentration and charge state of the native defects involved in the diffusion process, which affected the dopant and self-diffusion. The simultaneously recorded diffusion profiles enabled the modeling of the coupled dopant and self-diffusion. From the modeling of the simultaneous diffusion, the dopant diffusion mechanisms, the native defect charge states, and the self- and dopant diffusion coefficients can be determined. This information is necessary to enhance the physical modeling of dopant diffusion in Si. It is of particular interest to the modeling of future electronic Si devices, where the nanometer-scale features have created the need for precise physical models of atomic diffusion in Si. The modeling of the experimental profiles of simultaneous diffusion of B and Si under p-type extrinsic conditions revealed that both species are mediated by neutral and singly, positively charged Si self-interstitials. The diffusion of As and Si under extrinsic n-type conditions yielded a model consisting of the interstitialcy and vacancy mechanisms of diffusion via singly negatively charged self-interstitials and neutral vacancies. The simultaneous diffusion of P and Si has been modeled on the basis of neutral and singly negatively charged self-interstitials and neutral and singly positively charged P

  3. Progress in passive solar energy systems. Volume 8. Part 1

    SciTech Connect (OSTI)

    Hayes, J.; Andrejko, D.A.

    1983-01-01

    This book presents the papers given at a conference sponsored by the US DOE, the Solar Energy Research Institute, SolarVision, Inc., and the Southern California Solar Energy Society. The topics considered at the conference included sizing solar energy systems for agricultural applications, a farm scale ethanol production plant, the EEC wind energy RandD program, the passive solar performance assessment of an earth-sheltered house, the ARCO 1 MW photovoltaic power plant, the performance of a dendritic web photovoltaic module, second generation point focused concentrators, linear fresnel lens concentrating photovoltaic collectors, photovoltaic conversion efficiency, amorphous silicon thin film solar cells, a photovoltaic system for a shopping center, photovoltaic power generation for the utility industry, spectral solar radiation, and the analysis of insolation data.

  4. Concentrating Solar Power Projects - Xina Solar One | Concentrating Solar

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

    Power | NREL Xina Solar One Abengoa has been selected by the Department of Energy (DOE) of South Africa to develop Xina Solar One, a 100 MW parabolic trough plant with a five-hour thermal energy storage system using molten salts. This project will form the largest solar complex in Africa together with Abengoa's plant KaXu Solar One that is currently under construction in the country. Xina Solar One was awarded to Abengoa in the third round of renewable energy projects organized by the

  5. Compound Solar Technology CompSolar | Open Energy Information

    Open Energy Info (EERE)

    Solar Technology CompSolar Jump to: navigation, search Name: Compound Solar Technology (CompSolar) Place: Jhunan, Taiwan Zip: 350 Sector: Solar Product: Producer of glass-based...

  6. Silicon Valley Solar Inc SV Solar | Open Energy Information

    Open Energy Info (EERE)

    Solar Inc SV Solar Jump to: navigation, search Name: Silicon Valley Solar Inc (SV Solar) Place: Santa Clara, California Zip: 95051 Sector: Solar Product: A US-based manufacturer of...

  7. First Solar AVSR Solar Ranch Technical Eligibility Re-Evaluation...

    Office of Environmental Management (EM)

    First Solar AVSR Solar Ranch Technical Eligibility Re-Evaluation Memo First Solar AVSR Solar Ranch Technical Eligibility Re-Evaluation Memo FirstSolarAVSRSolarRanchOneTechnic...

  8. Caprolactam production by direct solar flux

    SciTech Connect (OSTI)

    Talukdar, J.; Wong, E.H.S.; Mathur, V.K. )

    1991-01-01

    The use of solar energy for the photonitrozation of cyclohexane for the production of cyclohexanone oxime hydrochloride, an intermediate for the manufacture of caprolactam, is discussed. Experimental results show the technical feasibility of such a reaction in the presence of radiation of wavelength 350-550 nm simulating sunlight.

  9. Semiconductor liquid-junction solar cell

    SciTech Connect (OSTI)

    Parkinson, B.A.

    1982-10-29

    A semiconductor liquid junction photocell in which the photocell is in the configuration of a light concentrator and in which the electrolytic solution both conducts current and facilitates the concentration of incident solar radiation onto the semiconductor. The photocell may be in the configuration of a non-imaging concentrator such as a compound parabolic concentrator, or an imaging concentrator such as a lens.

  10. Measurements and modeling of total solar irradiance in X-class solar flares

    SciTech Connect (OSTI)

    Moore, Christopher Samuel; Chamberlin, Phillip Clyde; Hock, Rachel

    2014-05-20

    The Total Irradiance Monitor (TIM) from NASA's SOlar Radiation and Climate Experiment can detect changes in the total solar irradiance (TSI) to a precision of 2 ppm, allowing observations of variations due to the largest X-class solar flares for the first time. Presented here is a robust algorithm for determining the radiative output in the TIM TSI measurements, in both the impulsive and gradual phases, for the four solar flares presented in Woods et al., as well as an additional flare measured on 2006 December 6. The radiative outputs for both phases of these five flares are then compared to the vacuum ultraviolet (VUV) irradiance output from the Flare Irradiance Spectral Model (FISM) in order to derive an empirical relationship between the FISM VUV model and the TIM TSI data output to estimate the TSI radiative output for eight other X-class flares. This model provides the basis for the bolometric energy estimates for the solar flares analyzed in the Emslie et al. study.

  11. SunShot Solar PV | Department of Energy

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

    Solar PV SunShot Solar PV

  12. Solar in Cold, Cloudy Climates

    Broader source: Energy.gov [DOE]

    Presentation delivered by Chuck Marken during the 2009 Northeastern Solar Cities Conference Solar Survey session.

  13. Tribal Solar Energy Partnerships

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

    SOLAR ENERGY PARTNERSHIPS Chairman Timothy Williams - Fort Mojave Indian Tribe Perry Fontana - First Solar Fort Mojave Indian Reservation Fort Mojave Project Site Mohave Generating ...

  14. Making a Solar Oven

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

    Students make solar ovens. Student background information is provided. The expected outcome is that students will learn about solar energy transfer.

  15. Solar PV Incentive Programs

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

    PV Program (greater than 50 kW) * LIPA Solar Pioneer (homeowner) & Solar Entrepreneur (business - up to 50 kW) Research & Development collaborations on BOS cost ...

  16. Your Solar Home

    Broader source: Energy.gov [DOE]

    Solar Schoolhouse Education supplement for the Sacramento Bee to introduce solar to elementary school children and introduce the design and AD contest for local students.

  17. TVA- Solar Solutions Initiative

    Broader source: Energy.gov [DOE]

    Solar Solutions Initiative (SSI) is a pilot program that offers additional financial incentives for Solar PV systems participating in the Renewable Standard Offer program. Applications for new...

  18. Solar Photovoltaic SPECIFICATION, CHECKLIST...

    Energy Savers [EERE]

    Ready Home SOLAR PHOTOVOLTAIC SPECIFICATION, CHECKLIST AND GUIDE i Table of Contents About the Renewable Energy Ready Home Specifications Assumptions of the RERH Solar ...

  19. Solar Power Basics

    Broader source: Energy.gov [DOE]

    This video summarizes the process of generating solar electricity from photovoltaic and concentrating solar power technologies. Research, manufacturing, and usage across the United States is also...

  20. Scattering Solar Thermal Concentrators

    Office of Environmental Management (EM)

    sunshot DOEGO-102012-3669 * September 2012 MOTIVATION All thermal concentrating solar power (CSP) systems use solar tracking, which involves moving large mirror surfaces...