ARK: Aggregation of Reads by K-Means for Estimation of Bacterial Community Composition.

Science.gov (United States)

Koslicki, David; Chatterjee, Saikat; Shahrivar, Damon; Walker, Alan W; Francis, Suzanna C; Fraser, Louise J; Vehkaperä, Mikko; Lan, Yueheng; Corander, Jukka

2015-01-01

Estimation of bacterial community composition from high-throughput sequenced 16S rRNA gene amplicons is a key task in microbial ecology. Since the sequence data from each sample typically consist of a large number of reads and are adversely impacted by different levels of biological and technical noise, accurate analysis of such large datasets is challenging. There has been a recent surge of interest in using compressed sensing inspired and convex-optimization based methods to solve the estimation problem for bacterial community composition. These methods typically rely on summarizing the sequence data by frequencies of low-order k-mers and matching this information statistically with a taxonomically structured database. Here we show that the accuracy of the resulting community composition estimates can be substantially improved by aggregating the reads from a sample with an unsupervised machine learning approach prior to the estimation phase. The aggregation of reads is a pre-processing approach where we use a standard K-means clustering algorithm that partitions a large set of reads into subsets with reasonable computational cost to provide several vectors of first order statistics instead of only single statistical summarization in terms of k-mer frequencies. The output of the clustering is then processed further to obtain the final estimate for each sample. The resulting method is called Aggregation of Reads by K-means (ARK), and it is based on a statistical argument via mixture density formulation. ARK is found to improve the fidelity and robustness of several recently introduced methods, with only a modest increase in computational complexity. An open source, platform-independent implementation of the method in the Julia programming language is freely available at https://github.com/dkoslicki/ARK. A Matlab implementation is available at http://www.ee.kth.se/ctsoftware.

SPECTRAL OPTICAL MONITORING OF THE NARROW-LINE SEYFERT 1 GALAXY Ark 564

International Nuclear Information System (INIS)

Shapovalova, A. I.; Burenkov, A. N.; Popović, L. Č.; Kovačević, J.; Chavushyan, V. H.; Valdes, J. R.; Torrealba, J.; Carrasco, L.; Ilić, D.; Kovačević, A.; Kollatschny, W.; Bochkarev, N. G.; León-Tavares, J.; Mercado, A.; Benítez, E.; Dultzin, D.; De la Fuente, E.

2012-01-01

We present the results of a long-term (1999-2010) spectral optical monitoring campaign of the active galactic nucleus (AGN) Ark 564, which shows a strong Fe II line emission in the optical. This AGN is a narrow-line Seyfert 1 (NLS1) galaxy, a group of AGNs with specific spectral characteristics. We analyze the light curves of the permitted Hα, Hβ, optical Fe II line fluxes, and the continuum flux in order to search for a time lag between them. Additionally, in order to estimate the contribution of iron lines from different multiplets, we fit the Hβ and Fe II lines with a sum of Gaussian components. We find that during the monitoring period the spectral variation (F max /F min ) of Ark 564 is between 1.5 for Hα and 1.8 for the Fe II lines. The correlation between the Fe II and Hβ flux variations is of higher significance than that of Hα and Hβ (whose correlation is almost absent). The permitted-line profiles are Lorentzian-like and do not change shape during the monitoring period. We investigate, in detail, the optical Fe II emission and find different degrees of correlation between the Fe II emission arising from different spectral multiplets and the continuum flux. The relatively weak and different degrees of correlations between permitted lines and continuum fluxes indicate a rather complex source of ionization of the broad-line emission region.

SPECTRAL OPTICAL MONITORING OF THE NARROW-LINE SEYFERT 1 GALAXY Ark 564

Energy Technology Data Exchange (ETDEWEB)

Shapovalova, A. I.; Burenkov, A. N. [Special Astrophysical Observatory of the Russian AS, Nizhnij Arkhyz, Karachaevo-Cherkesia 369167 (Russian Federation); Popovic, L. C.; Kovacevic, J. [Astronomical Observatory, Volgina 7, 11160 Belgrade 74 (Serbia); Chavushyan, V. H.; Valdes, J. R.; Torrealba, J.; Carrasco, L. [Instituto Nacional de Astrofisica, Optica y Electronica, Apartado Postal 51-216, 72000 Puebla (Mexico); Ilic, D.; Kovacevic, A. [Isaac Newton Institute of Chile, Yugoslavia Branch, Belgrade (Serbia); Kollatschny, W. [Institut fuer Astrophysik, Georg-August-Universitaet, Goettingen (Germany); Bochkarev, N. G. [Sternberg Astronomical Institute, Moscow (Russian Federation); Leon-Tavares, J. [Aalto University Metsaehovi Radio Observatory, Metsaehovintie 114, FIN-02540 Kylmaelae (Finland); Mercado, A. [Universidad Politecnica de Baja California, Av. de la Industria 291, 21010 Mexicali, B.C. (Mexico); Benitez, E.; Dultzin, D. [Instituto de Astronomia, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-264, Mexico, D.F. 04510 (Mexico); De la Fuente, E., E-mail: ashap@sao.ru [Instituto de Astronomia y Meteorologia, Dpto. de Fisica CUCEI, Universidad de Guadalajara, Av. Vallarta 2602, 44130 Guadalajara, Jalisco (Mexico)

2012-09-15

We present the results of a long-term (1999-2010) spectral optical monitoring campaign of the active galactic nucleus (AGN) Ark 564, which shows a strong Fe II line emission in the optical. This AGN is a narrow-line Seyfert 1 (NLS1) galaxy, a group of AGNs with specific spectral characteristics. We analyze the light curves of the permitted H{alpha}, H{beta}, optical Fe II line fluxes, and the continuum flux in order to search for a time lag between them. Additionally, in order to estimate the contribution of iron lines from different multiplets, we fit the H{beta} and Fe II lines with a sum of Gaussian components. We find that during the monitoring period the spectral variation (F{sub max}/F{sub min}) of Ark 564 is between 1.5 for H{alpha} and 1.8 for the Fe II lines. The correlation between the Fe II and H{beta} flux variations is of higher significance than that of H{alpha} and H{beta} (whose correlation is almost absent). The permitted-line profiles are Lorentzian-like and do not change shape during the monitoring period. We investigate, in detail, the optical Fe II emission and find different degrees of correlation between the Fe II emission arising from different spectral multiplets and the continuum flux. The relatively weak and different degrees of correlations between permitted lines and continuum fluxes indicate a rather complex source of ionization of the broad-line emission region.

"It's All Shiny and There's No Pollution": "Barbapapa's Ark," Environmental Influences

Science.gov (United States)

Lowe, Virginia

2013-01-01

The environmental picture book "Barbapapa's Ark" was published in 1974. I was keeping a parent-observer record of my two children at the time. The book had a strong influence on them from ages three to six, moving them to query pollution and hunting, in book and environment, and as adults, becoming committed activists for the…

Prevajanje športne terminologije v priročniku Osnove košarke NBA

OpenAIRE

Kajič, Matic

2016-01-01

Pri prevajanju strokovnih besedil ne gre le za vestno opravljanje veščin, ampak za visoko intelektualno delovanje: reševanje vedno novih problemov. To velja tudi za košarkarsko terminologijo, saj obstaja veliko ameriških košarkarskih izrazov, za katere nimamo ustreznic v slovenskem jeziku. Posebnost priročnika Osnove košarke NBA avtorja Marka Vancila se kaže v velikem številu strokovnega košarkarskega izrazja, ki od prevajalca zahteva veliko mero strokovnega poznavanja področja. V diplomskem ...

Plate motions, Gondwana dinosaurs, Noah's arks, beached Viking funeral ships, ghost ships, and landspans.

Science.gov (United States)

Jacobs, Louis L; Strganac, Christopher; Scotese, Christopher

2011-03-01

Gondwana landmasses have served as large-scale biogeographic Noah's Arks and Beached Viking Funeral Ships, as defined by McKenna. The latitudinal trajectories of selected Gondwana dinosaur localities were traced through time in order to evaluate their movement through climate zones relative to those in which they originally formed. The dispersal of fauna during the breakup of Gondwana may have been facilitated by the presence of offshelf islands forming landspans (sensu Iturralde-Vinent and MacPhee) in the Equatorial Atlantic Gateway and elsewhere.

XMM-Newton observation of the NLS1 galaxy Ark 564. I. Spectral analysis of the time-average spectrum

NARCIS (Netherlands)

Papadakis, I.E.; Brinkmann, W.; Page, M.J.; McHardy, I.; Uttley, P.

2007-01-01

Context: .We present the results from the spectral analysis of the time-average spectrum of the Narrow Line Seyfert 1 (NLS1) galaxy Ark 564 from a ~100 ks XMM-Newton observation. Aims: .Our aim is to characterize accurately the shape of the time-average, X-ray continuum spectrum of the source and

The soft-X-ray emission of Ark 120. XMM-Newton, NuSTAR, and the importance of taking the broad view

DEFF Research Database (Denmark)

Matt, G.; Marinucci, A.; Guainazzi, M.

2014-01-01

We present simultaneous XMM-Newton and NuSTAR observations of the 'bare' Seyfert 1 galaxy, Ark 120, a system in which ionized absorption is absent. The NuSTAR hard-X-ray spectral coverage allows us to constrain different models for the excess soft-X-ray emission. Among phenomenological models, a ...

Deşifre Şarkı Söyleme Eğitimine Yönelik Öğretim Metodu Önerisi A Recommended Teaching Method For Sight-Singing Education

Directory of Open Access Journals (Sweden)

Sevan NART

2013-03-01

Full Text Available In professional music education, effort is made during musicallistening, reading, and writing (MLRW courses to teach the language ofmusic. Sight-singing education is related to the musical readingdimension of MLRW teaching. Sight-singing is the ability (skill toanalyse and vocalize a music piece directly with words at first sight inaccordance with the correct notation. This skill which can be consideredthe highest step in musical literacy at professional music education is askill that every individual studying music education needs to develop.Sight-singing skills that each individual have at a certain level can beimproved by planned, programmed, systematic and regular studies.In Turkey, there are very limited unique studies for improvingsight-reading skills. And as for sight-singing there are no systematic,planned applications, scientific researches or resourcesare available. However there are a great number of publishedresources available for teaching sight- singing, and many methods arebeeing practiced successfully in overseas since 1800s.The method which is proposed as a teaching material for sightsingingin this study was a unique teaching method that was developedand experimented for a doctoral research with the idea of resolving thelack of resource in the field of sight-singing. This study consistsof descriptions for the proposed- teaching method and system for sightsingingand also explanations about the devoloping process of thecirriculumn and teaching materials.The aforementioned method is important for being the very firstwriten teaching method about sight singing education in Turkey. It alsohas importance in terms of being an example and resource for leadingfuture studies, cirriculumns and practices in this area. Mesleki müzik eğitiminde öğrencilere müziksel işitme, okuma veyazma (MİOY dersleri kapsamında müziğin dili öğretilmeyeçalışılmaktadır. Deşifre şarkı söyleme MİOY öğretiminin müzikselokuma boyutuyla ili

ARkStorm@Tahoe: Stakeholder perspectives on vulnerabilities and preparedness for an extreme storm event in the greater Lake Tahoe, Reno, and Carson City region

Science.gov (United States)

Albano, Christine M.; Cox, Dale A.; Dettinger, Michael; Shaller, Kevin; Welborn, Toby L.; McCarthy, Maureen

2014-01-01

Atmospheric rivers (ARs) are strongly linked to extreme winter precipitation events in the Western U.S., accounting for 80 percent of extreme floods in the Sierra Nevada and surrounding lowlands. In 2010, the U.S. Geological Survey developed the ARkStorm extreme storm scenario for California to quantify risks from extreme winter storms and to allow stakeholders to better explore and mitigate potential impacts. To explore impacts on natural resources and communities in montane and adjacent environments, we downscaled the scenario to the greater Lake Tahoe, Reno and Carson City region of northern Nevada and California. This ArkStorm@Tahoe scenario was presented at six stakeholder meetings, each with a different geographic and subject matter focus. Discussions were facilitated by the ARkStorm@Tahoe team to identify social and ecological vulnerabilities to extreme winter storms, science and information needs, and proactive measures that might minimize impacts from this type of event. Information collected in these meetings was used to develop a tabletop emergency response exercise and set of recommendations for increasing resilience to extreme winter storm events in both Tahoe and the downstream communities of Northern Nevada.Over 300 individuals participated in ARkStorm@Tahoe stakeholder meetings and the emergency response exercise, including representatives from emergency response, natural resource and ecosystem management, health and human services, public utilities, and businesses. Interruption of transportation, communications, and lack of power and backup fuel supplies were identified as the most likely and primary points of failure across multiple sectors and geographies, as these interruptions have cascading effects on natural and human systems by impeding emergency response efforts. Other key issues that arose in discussions included contamination risks to water supplies and aquatic ecosystems, especially in the Tahoe Basin and Pyramid Lake, interagency

Atmospheric solar heating rate in the water vapor bands

Science.gov (United States)

Chou, Ming-Dah

1986-01-01

The total absorption of solar radiation by water vapor in clear atmospheres is parameterized as a simple function of the scaled water vapor amount. For applications to cloudy and hazy atmospheres, the flux-weighted k-distribution functions are computed for individual absorption bands and for the total near-infrared region. The parameterization is based upon monochromatic calculations and follows essentially the scaling approximation of Chou and Arking, but the effect of temperature variation with height is taken into account in order to enhance the accuracy. Furthermore, the spectral range is extended to cover the two weak bands centered at 0.72 and 0.82 micron. Comparisons with monochromatic calculations show that the atmospheric heating rate and the surface radiation can be accurately computed from the parameterization. Comparisons are also made with other parameterizations. It is found that the absorption of solar radiation can be computed reasonably well using the Goody band model and the Curtis-Godson approximation.

Strindberg på färöiska : En analys av Ett halvt ark papper

OpenAIRE

Qureshi, Karl

2007-01-01

Syftet med denna uppsats är att ge en insikt i hur den färöiska översättningen av Strindbergs novell Ett halvt ark papper förhåller sig till originalet i fråga om syntax och ordbildning ur ett såväl grammatiskt som semantiskt perspektiv. Metoden som tillämpas är en kvalitativ-komparativ metod som har sitt ursprung i en kombination av kopplingsanalys och komponentanalys. Resultatet av materialet visar att måltextens syntax överlag överensstämmer med syntaxen i källtexten med ett fåtal konsekve...

Anticipating and Communicating Plausible Environmental and Health Concerns Associated with Future Disasters: The ShakeOut and ARkStorm Scenarios as Examples

Science.gov (United States)

Plumlee, G. S.; Morman, S. A.; Alpers, C. N.; Hoefen, T. M.; Meeker, G. P.

2010-12-01

Disasters commonly pose immediate threats to human safety, but can also produce hazardous materials (HM) that pose short- and long-term environmental-health threats. The U.S. Geological Survey (USGS) has helped assess potential environmental health characteristics of HM produced by various natural and anthropogenic disasters, such as the 2001 World Trade Center collapse, 2005 hurricanes Katrina and Rita, 2007-2009 southern California wildfires, various volcanic eruptions, and others. Building upon experience gained from these responses, we are now developing methods to anticipate plausible environmental and health implications of the 2008 Great Southern California ShakeOut scenario (which modeled the impacts of a 7.8 magnitude earthquake on the southern San Andreas fault, http://urbanearth.gps.caltech.edu/scenario08/), and the recent ARkStorm scenario (modeling the impacts of a major, weeks-long winter storm hitting nearly all of California, http://urbanearth.gps.caltech.edu/winter-storm/). Environmental-health impacts of various past earthquakes and extreme storms are first used to identify plausible impacts that could be associated with the disaster scenarios. Substantial insights can then be gleaned using a Geographic Information Systems (GIS) approach to link ShakeOut and ARkStorm effects maps with data extracted from diverse database sources containing geologic, hazards, and environmental information. This type of analysis helps constrain where potential geogenic (natural) and anthropogenic sources of HM (and their likely types of contaminants or pathogens) fall within areas of predicted ShakeOut-related shaking, firestorms, and landslides, and predicted ARkStorm-related precipitation, flooding, and winds. Because of uncertainties in the event models and many uncertainties in the databases used (e.g., incorrect location information, lack of detailed information on specific facilities, etc.) this approach should only be considered as the first of multiple steps

An efficient method for computing the absorption of solar radiation by water vapor

Science.gov (United States)

Chou, M.-D.; Arking, A.

1981-01-01

Chou and Arking (1980) have developed a fast but accurate method for computing the IR cooling rate due to water vapor. Using a similar approach, the considered investigation develops a method for computing the heating rates due to the absorption of solar radiation by water vapor in the wavelength range from 4 to 8.3 micrometers. The validity of the method is verified by comparison with line-by-line calculations. An outline is provided of an efficient method for transmittance and flux computations based upon actual line parameters. High speed is achieved by employing a one-parameter scaling approximation to convert an inhomogeneous path into an equivalent homogeneous path at suitably chosen reference conditions.

A deep X-ray view of the bare AGN Ark 120. IV. XMM-Newton and NuSTAR spectra dominated by two temperature (warm, hot) Comptonization processes

Science.gov (United States)

Porquet, D.; Reeves, J. N.; Matt, G.; Marinucci, A.; Nardini, E.; Braito, V.; Lobban, A.; Ballantyne, D. R.; Boggs, S. E.; Christensen, F. E.; Dauser, T.; Farrah, D.; Garcia, J.; Hailey, C. J.; Harrison, F.; Stern, D.; Tortosa, A.; Ursini, F.; Zhang, W. W.

2018-01-01

Context. The physical characteristics of the material closest to supermassive black holes (SMBHs) are primarily studied through X-ray observations. However, the origins of the main X-ray components such as the soft X-ray excess, the Fe Kα line complex, and the hard X-ray excess are still hotly debated. This is particularly problematic for active galactic nuclei (AGN) showing a significant intrinsic absorption, either warm or neutral, which can severely distort the observed continuum. Therefore, AGN with no (or very weak) intrinsic absorption along the line of sight, so-called "bare AGN", are the best targets to directly probe matter very close to the SMBH. Aims: We perform an X-ray spectral analysis of the brightest and cleanest bare AGN known so far, Ark 120, in order to determine the process(es) at work in the vicinity of the SMBH. Methods: We present spectral analyses of data from an extensive campaign observing Ark 120 in X-rays with XMM-Newton (4 × 120 ks, 2014 March 18-24), and NuSTAR (65.5 ks, 2014 March 22). Results: During this very deep X-ray campaign, the source was caught in a high-flux state similar to the earlier 2003 XMM-Newton observation, and about twice as bright as the lower-flux observation in 2013. The spectral analysis confirms the "softer when brighter" behavior of Ark 120. The four XMM-Newton/pn spectra are characterized by the presence of a prominent soft X-ray excess and a significant Fe Kα complex. The continuum is very similar above about 3 keV, while significant variability is present for the soft X-ray excess. We find that relativistic reflection from a constant-density, flat accretion disk cannot simultaneously produce the soft excess, broad Fe Kα complex, and hard X-ray excess. Instead, Comptonization reproduces the broadband (0.3-79 keV) continuum well, together with a contribution from a mildly relativistic disk reflection spectrum. Conclusions: During this 2014 observational campaign, the soft X-ray spectrum of Ark 120 below 0

DISCOVERY OF RELATIVISTIC OUTFLOW IN THE SEYFERT GALAXY Ark 564

International Nuclear Information System (INIS)

Gupta, A.; Mathur, S.; Krongold, Y.; Nicastro, F.

2013-01-01

We present Chandra High Energy Transmission Grating Spectra of the narrow-line Seyfert-1 galaxy Ark 564. The spectrum shows numerous absorption lines which are well modeled with low-velocity outflow components usually observed in Seyfert galaxies. There are, however, some residual absorption lines which are not accounted for by low-velocity outflows. Here, we present identifications of the strongest lines as Kα transitions of O VII (two lines) and O VI at outflow velocities of ∼0.1c. These lines are detected at 6.9σ, 6.2σ, and 4.7σ, respectively, and cannot be due to chance statistical fluctuations. Photoionization models with ultra-high velocity components improve the spectral fit significantly, providing further support for the presence of relativistic outflow in this source. Without knowing the location of the absorber, its mass and energy outflow rates cannot be well constrained; we find E-dot (outflow)/L bol lower limit of ≥0.006% assuming a bi-conical wind geometry. This is the first time that absorption lines with ultra-high velocities are unambiguously detected in the soft X-ray band. The presence of outflows with relativistic velocities in active galactic nuclei (AGNs) with Seyfert-type luminosities is hard to understand and provides valuable constraints to models of AGN outflows. Radiation pressure is unlikely to be the driving mechanism for such outflows and magnetohydrodynamic may be involved

Plate motions, Gondwana Dinosaurs, Noah's Arks, Beached Viking Funeral Ships, Ghost Ships, and Landspans

Directory of Open Access Journals (Sweden)

Louis L. Jacobs

2011-03-01

Full Text Available Gondwana landmasses have served as large-scale biogeographic Noah's Arks and Beached Viking Funeral Ships, as defined by McKenna. The latitudinal trajectories of selected Gondwana dinosaur localities were traced through time in order to evaluate their movement through climate zones relative to those in which they originally formed. The dispersal of fauna during the breakup of Gondwana may have been facilitated by the presence of offshelf islands forming landspans (sensu Iturralde-Vinent and MacPhee in the Equatorial Atlantic Gateway and elsewhere.As massas de terra do Gondwana serviram como Arcas de Noe biogeograficas de grande escala e Navios Funerarios Vikings encalhados, conforme definido por McKenna. As trajetorias latitudinais de areas selecionadas de dinossauros do Gondwana foram tracadas ao longo do tempo a fim de avaliar seu movimento atraves de zonas climaticas relativas aquelas nas quais elas foram originalmente formadas. A dispersao da fauna durante a quebra do Gondwana pode ter sido facilitada pela presenca de ilhas oceanicas formando extensoes de terra (sensu Iturralde-Vinent e MacPhee na entrada do Atlantico Equatorial e em outros lugares.

Experimental evaluation of fluorescent (alizarin red S and calcein) and clip-tag markers for stock assessment of ark shell, Anadara broughtonii

Science.gov (United States)

Zhou, Shanshan; Zhang, Xiumei; Li, Wentao; Li, Long; Cai, Xingyuan

2017-03-01

Release programs to enhance stocks of ark shell ( Anadara broughtonii) have been undertaken in a number of Asian countries, but their effectiveness has rarely been investigated owing to a lack of marking methods. The quality and longevity of fluorescent markers, alizarin red S (ARS) and calcein (CAL) (200 and 300 mg/L), as well as clip tags, were tested on juvenile A. broughtonii. No significant differences in survival or shell growth were observed in juveniles stained with either of the two fluorochromes after a 160-day culture period, but the retention rate was 100% after 1 year. Fluorescent marks (≥grade 3) were observable microscopically in juveniles stained with the two fluorochromes, and some fluorescent marks (≥grade 4) were visible with the naked eye after 1 year. ARS-marked shells were brighter than those marked with CAL, and shells marked with 300 mg/L of the fluorochromes were easier to detect than those marked with 200 mg/L. Clip tags were incorporated into the shell as the bivalve grew, and the retention rate was 64.25% after 160 days. Significant differences in survival (at 30 days), shell length (at 60, 90, 120, and 160 days), and wet weight (at 90, 120, and 160 days) were observed between the clip-tagged and control groups (all P< 0.05), indicating that the tags may have passive effects on the ark shell. The results suggest that both ARS and CAL are suitable to mark A. broughtonii for large-scale restocking programs, and that optimal marking quality was achieved with 300 mg/L ARS. Lighter and smaller clip tags need to be developed to reduce injury and increase survival rate of clams.

Ark and Archive: Making a Place for Long-Term Research on Barro Colorado Island, Panama.

Science.gov (United States)

Raby, Megan

2015-12-01

Barro Colorado Island (BCI), Panama, may be the most studied tropical forest in the world. A 1,560-hectare island created by the flooding of the Panama Canal, BCI became a nature reserve and biological research station in 1923. Contemporaries saw the island as an "ark" preserving a sample of primeval tropical nature for scientific study. BCI was not simply "set aside," however. The project of making it a place for science significantly reshaped the island through the twentieth century. This essay demonstrates that BCI was constructed specifically to allow long-term observation of tropical organisms--their complex behaviors, life histories, population dynamics, and changing species composition. An evolving system of monitoring and information technology transformed the island into a living scientific "archive," in which the landscape became both an object and a repository of scientific knowledge. As a research site, BCI enabled a long-term, place-based form of collective empiricism, focused on the study of the ecology of a single tropical island. This essay articulates tropical ecology as a "science of the archive" in order to examine the origins of practices of environmental surveillance that have become central to debates about global change and conservation.

Mammalian collection on Noah's Ark: the effects of beauty, brain and body size.

Directory of Open Access Journals (Sweden)

Daniel Frynta

Full Text Available The importance of today's zoological gardens as the so-called "Noah's Ark" grows as the natural habitat of many species quickly diminishes. Their potential to shelter a large amount of individuals from many species gives us the opportunity to reintroduce a species that disappeared in nature. However, the selection of animals to be kept in zoos worldwide is highly selective and depends on human decisions driven by both ecological criteria such as population size or vulnerability and audience-driven criteria such as aesthetic preferences. Thus we focused our study on the most commonly kept and bred animal class, the mammals, and we asked which factors affect various aspects of the mammalian collection of zoos. We analyzed the presence/absence, population size, and frequency per species of each of the 123 mammalian families kept in the worldwide zoo collection. Our aim was to explain these data using the human-perceived attractiveness of mammalian families, their body weight, relative brain size and species richness of the family. In agreement with various previous studies, we found that the body size and the attractiveness of mammals significantly affect all studied components of the mammalian collection of zoos. There is a higher probability of the large and attractive families to be kept. Once kept, these animals are presented in larger numbers in more zoos. On the contrary, the relative mean brain size only affects the primary selection whether to keep the family or not. It does not affect the zoo population size or the number of zoos that keep the family.

Aliisedimentitalea scapharcae gen. nov., sp. nov., isolated from ark shell Scapharca broughtonii.

Science.gov (United States)

Kim, Young-Ok; Park, Sooyeon; Nam, Bo-Hye; Kim, Dong-Gyun; Won, Sung-Min; Park, Ji-Min; Yoon, Jung-Hoon

2015-08-01

A Gram-negative, aerobic, non-spore-forming, motile and ovoid or rod-shaped bacterial strain, designated MA2-16(T), was isolated from ark shell (Scapharca broughtonii) collected from the South Sea, South Korea. Strain MA2-16(T) was found to grow optimally at 30°C, at pH 7.0-8.0 and in the presence of 2.0% (w/v) NaCl. Neighbour-joining, maximum-likelihood and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences revealed that strain MA2-16(T) clustered with the type strain of Sedimentitalea nanhaiensis. The novel strain exhibited a 16S rRNA gene sequence similarity value of 97.1% to the type strain of S. nanhaiensis. In the neighbour-joining phylogenetic tree based on gyrB sequences, strain MA2-16(T) formed an evolutionary lineage independent of those of other taxa. Strain MA2-16(T) contained Q-10 as the predominant ubiquinone and C18:1 ω7c and 11-methyl C18:1 ω7c as the major fatty acids. The major polar lipids of strain MA2-16(T) were phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, an unidentified aminolipid and an unidentified lipid. The DNA G+C content of strain MA2-16(T) was 57.7 mol% and its DNA-DNA relatedness values with the type strains of S. nanhaiensis and some phylogenetically related species of the genera Leisingera and Phaeobacter were 13-24%. On the basis of the data presented, strain MA2-16(T) is considered to represent a novel genus and novel species within the family Rhodobacteraceae, for which the name Aliisedimentitalea scapharcae gen. nov., sp. nov. is proposed. The type strain is MA2-16(T) (=KCTC 42119(T) =CECT 8598(T)).

The usability of ark clam shell (Anadara granosa) as calcium precursor to produce hydroxyapatite nanoparticle via wet chemical precipitate method in various sintering temperature.

Science.gov (United States)

Khiri, Mohammad Zulhasif Ahmad; Matori, Khamirul Amin; Zainuddin, Norhazlin; Abdullah, Che Azurahanim Che; Alassan, Zarifah Nadakkavil; Baharuddin, Nur Fadilah; Zaid, Mohd Hafiz Mohd

2016-01-01

This paper reported the uses of ark clam shell calcium precursor in order to form hydroxyapatite (HA) via the wet chemical precipitation method. The main objective of this research is to acquire better understanding regarding the effect of sintering temperature in the fabrication of HA. Throughout experiment, the ratio of Ca:P were constantly controlled, between 1.67 and 2.00. The formation of HA at these ratio was confirmed by means of energy-dispersive X-ray spectroscopy analysis. In addition, the effect of sintering temperature on the formation of HA was observed using X-ray diffraction analysis, while the structural and morphology was determined by means of field emission scanning electron microscopy. The formation of HA nanoparticle was recorded (~35-69 nm) in the form of as-synthesize HA powder. The bonding compound appeared in the formation of HA was carried out using Fourier transform infrared spectroscopy such as biomaterials that are expected to find potential applications in orthopedic and biomedical industries .

Evaluation of infectious bronchitis virus Arkansas-type vaccine failure in commercial broilers.

Science.gov (United States)

Roh, Ha-Jung; Hilt, Deborah A; Williams, Susan M; Jackwooda, Mark W

2013-06-01

Infectious bronchitis virus (IBV) causes an upper respiratory tract disease in chickens and is highly contagious. Many different types of the virus exist, but only a few types are used as attenuated live vaccines in the commercial poultry industry. Of the vaccine types used, the Arkansas (Ark)-type virus is most frequently reisolated from vaccinated broilers. Previous research has suggested that incomplete clearance of Ark-type vaccine virus plays a role in the inadequate protection observed when vaccinated broilers are challenged with pathogenic Ark virus. In this study, we examine routes of vaccine administration using multiple IBV types including Ark in an effort to understand why Ark vaccines do not provide good protection and persist in commercial broilers. We found that interference between different types of IBV vaccines was not occurring when combined and administered using a commercial hatchery spray cabinet. Also, Ark vaccine virus was not efficacious in 1-day-old broilers when sprayed using a hatchery spray cabinet, but it gave good protection when administrated by eyedrop inoculation. We also found that the amount of Ark vaccine virus was low or undetectable in choanal swabs out to 35 days postvaccination when vaccine was administered by eyedrop or drinking water. Alternatively, a subpopulation of the Ark vaccine isolated from a vaccinated bird, Ark-RI-EP1, showed a peak titer at 7-10 days of age when given by the same routes, suggesting that the Ark-RI-EP1 was more fit with regard to infection, replication in the birds, or both. Moreover, we found that detection of IBV vaccine virus early after administration, regardless of strain or route, correlated with protection against homologous challenge and may thus be a good indicator of vaccine efficacy in the field because humoral antibody titers are typically low or undetectable after vaccination. These experiments provided key findings that can be used to direct efforts for improving the efficacy of IBV

Hatchery Spray Cabinet Administration Does Not Damage Avian Coronavirus Infectious Bronchitis Virus Vaccine Based on Analysis by Electron Microscopy and Virus Titration.

Science.gov (United States)

Roh, Ha-Jung; Jordan, Brian J; Hilt, Deborah A; Ard, Mary B; Jackwood, Mark W

2015-03-01

studies in our laboratory showed that the Arkansas-Delmarva Poultry Industry (Ark-DPI) vaccine given to 1-day-old chickens by hatchery spray cabinet replicated poorly and failed to adequately protect broilers against homologous virus challenge, whereas the same vaccine given by eye-drop did replicate and the birds were protected following homologous virus challenge. To determine if mechanical damage following spray application plays a role in failure of the Ark-DPI vaccine, we examined the morphology of three Ark-DPI vaccines from different manufacturers using an electron microscope and included a Massachusetts (Mass) vaccine as control. One of the Ark-DPI vaccines (vaccine A) and the Mass vaccine had significantly (P vaccines. We also found that the Ark-DPI and Mass vaccines had significantly (P vaccine titer before and after spray in embryonated eggs and found that both Ark-DPI and Mass vaccines had a similar drop in titer, 0.40 logi and 0.310 logi, respec10ively. Based on these data, it appears that mechanical damage to the Ark-DPI vaccine is not occurring when delivered by a hatchery spray cabinet, suggesting that some other factor is contributing to the failure of that vaccine when given by that method.

A deep X-ray view of the bare AGN Ark 120. III. X-ray timing analysis and multiwavelength variability

Science.gov (United States)

Lobban, A. P.; Porquet, D.; Reeves, J. N.; Markowitz, A.; Nardini, E.; Grosso, N.

2018-03-01

We present the spectral/timing properties of the bare Seyfert galaxy Ark 120 through a deep ˜420 ks XMM-Newton campaign plus recent NuSTAR observations and a ˜6-month Swift monitoring campaign. We investigate the spectral decomposition through fractional rms, covariance and difference spectra, finding the mid- to long-time-scale (˜day-year) variability to be dominated by a relatively smooth, steep component, peaking in the soft X-ray band. Additionally, we find evidence for variable Fe K emission redward of the Fe Kα core on long time-scales, consistent with previous findings. We detect a clearly defined power spectrum which we model with a power law with a slope of α ˜ 1.9. By extending the power spectrum to lower frequencies through the inclusion of Swift and Rossi X-ray Timing Explorer data, we find tentative evidence of a high-frequency break, consistent with existing scaling relations. We also explore frequency-dependent Fourier time lags, detecting a negative (`soft') lag for the first time in this source with the 0.3-1 keV band lagging behind the 1-4 keV band with a time delay, τ, of ˜900 s. Finally, we analyse the variability in the optical and ultraviolet (UV) bands using the Optical/UV Monitor onboard XMM-Newton and the Ultra-Violet/Optical Telescope onboard Swift and search for time-dependent correlations between the optical/UV/X-ray bands. We find tentative evidence for the U-band emission lagging behind the X-rays with a time delay of τ = 2.4 ± 1.8 d, which we discuss in the context of disc reprocessing.

Mobile robot for hazardous environments

International Nuclear Information System (INIS)

Bains, N.

1995-01-01

This paper describes the architecture and potential applications of the autonomous robot for a known environment (ARK). The ARK project has developed an autonomous mobile robot that can move around by itself in a complicated nuclear environment utilizing a number of sensors for navigation. The primary sensor system is computer vision. The ARK has the intelligence to determine its position utilizing open-quotes natural landmarks,close quotes such as ordinary building features at any point along its path. It is this feature that gives ARK its uniqueness to operate in an industrial type of environment. The prime motivation to develop ARK was the potential application of mobile robots in radioactive areas within nuclear generating stations and for nuclear waste sites. The project budget is $9 million over 4 yr and will be completed in October 1995

MSc Dissertation

DEFF Research Database (Denmark)

Roued-Cunliffe, Henriette

2008-01-01

Heritage Portals are in this dissertation defined as deep portals which can give access to external resource contents. This dissertation has developed such a portal which accesses the Swedish SMR, FMIS and the ARK system developed by L – P : Archaeology through web services. The development...... of the web Service for the ARK system was done as a part of this project combined with the creating of a WFS web-mapping service serving the spatial part of the dataset collected as a part of the Sintana project. The textual part of this dataset has been incorporated into an ARK system in the same way...... that the Portus project dataset was. Both these projects are available through the ARK web service. The portal accessed the FMIS and ARK web service and re-maps the XML output to Midas standard formatted XML and combined them. This allows the portal to do a cross-search of the two datasets and return the data...

Studies on Freezing of Shell-Fish-I

Science.gov (United States)

Song, Dae Jin; Konagaya, Shiro; Tanaka, Takeo

Ark shell, Anadara broughtonii(Shrenk), are commonly eaten raw or under-done in Korea, Japan, and East Asian countries. Along with a recent remarkable development of culture fisheries, Ark shell has become one of the commercially important shell-fish species. Transportation and storage of large quantities of shell-fish is becoming increasingly important. This work was begun with this background to make clear the effects of temperature and length of storage time on the quality of frozen stored ark shell. Results are as follows : (1) There was little chang in amounts of free and expressible drip from ark shell flesh frozen stored at -40°CdegC for 6 months. Water holding capacity of the same meat was almost constant over 6 months storage. However, a mounts of both drip increased markedly after 2 months storage at -10°C. (2) Protein extractibility of ark shell flesh tended to decrease gradually from the begining when stored at -10°C, while at -20°C, the protein extractibility was stable for 3 months before decreasing gradually. However at -40°C, the protein extractibility was stable for 6 months. It was found that paramyosin was very stable even when the ark shell was frozen stored at -10°C. (3) It was observed that ark shell flesh became tough when frozen. The toughness of ark shell flesh as measured by an instrument increased with frozen storage time and increased temperature. (4) In the smooth muscle, it was histologically observed that initial small ice crystals formed between muscle bundles grew larger during frozen storage. It was found that the higher the storage temperature, the bigger the ice crystals formed. Aggregation of some muscle fiber and empty spaces between muscle bundles were observd after thawed muscles frozen stored at relatively high temperature such as -10°C.

Environmentally appropriate technology, part 2

International Nuclear Information System (INIS)

McCallum, B.

1976-01-01

In this his second article on alternatives to thermally generated electricity, the author considers the economics of solar heating in Canada and existing or planned demonstration projects. Solar heating is at its best in February and March; it is admitted that December and January are dark months. Most solar-heated houses incorporate large heat-storage systems, but some only store heat for a day or two, and they, naturally, are cheaper. For an example of the cheaper type, a group at McGill Univ. has built four innovative houses for Indians in Quebec, with partial solar heating. For a more elaborate example, the New Alchemy Institute 'Ark' on Prince Edward Islnd includes greenhouses, fishponds and windmills. The author calculates that at 20% inflation of oil, gas and electricity prices, the annual cost of a house with 75% solar and 25% electric heating will rise from about $940 to about $5300 in 20 years, whereas that of oil or gas heating will rise from $600 to about $15,000. (N.D.H.)

Concentrating Solar Power Projects - Planta Solar 20 | Concentrating Solar

Science.gov (United States)

Power | NREL 20 This page provides information on Planta Solar 20, a concentrating solar power Solar's Planta Solar 20 (PS20) is a 20-megawatt power tower plant being constructed next to the PS10 tower and increasing incident solar radiation capture will increase net electrical power output by 10

Hybrids of Solar Sail, Solar Electric, and Solar Thermal Propulsion for Solar-System Exploration

Science.gov (United States)

Wilcox, Brian H.

2012-01-01

Solar sails have long been known to be an attractive method of propulsion in the inner solar system if the areal density of the overall spacecraft (S/C) could be reduced to approx.10 g/sq m. It has also long been recognized that the figure (precise shape) of useful solar sails needs to be reasonably good, so that the reflected light goes mostly in the desired direction. If one could make large reflective surfaces with reasonable figure at an areal density of approx.10 g/sq m, then several other attractive options emerge. One is to use such sails as solar concentrators for solar-electric propulsion. Current flight solar arrays have a specific output of approx. 100W/kg at 1 Astronomical Unit (AU) from the sun, and near-term advances promise to significantly increase this figure. A S/C with an areal density of 10 g/sq m could accelerate up to 29 km/s per year as a solar sail at 1 AU. Using the same sail as a concentrator at 30 AU, the same spacecraft could have up to approx. 45 W of electric power per kg of total S/C mass available for electric propulsion (EP). With an EP system that is 50% power-efficient, exhausting 10% of the initial S/C mass per year as propellant, the exhaust velocity is approx. 119 km/s and the acceleration is approx. 12 km/s per year. This hybrid thus opens attractive options for missions to the outer solar system, including sample-return missions. If solar-thermal propulsion were perfected, it would offer an attractive intermediate between solar sailing in the inner solar system and solar electric propulsion for the outer solar system. In the example above, both the solar sail and solar electric systems don't have a specific impulse that is near-optimal for the mission. Solar thermal propulsion, with an exhaust velocity of the order of 10 km/s, is better matched to many solar system exploration missions. This paper derives the basic relationships between these three propulsion options and gives examples of missions that might be enabled by

Concentrating Solar Power Projects - Khi Solar One | Concentrating Solar

Science.gov (United States)

Power | NREL Khi Solar One This page provides information on Khi Solar One, a concentrating solar power (CSP) project, with data organized by background, parcipants and power plant configuration . Status Date: February 8, 2016 Project Overview Project Name: Khi Solar One Country: South Africa Location

Concentrating Solar Power Projects - Nevada Solar One | Concentrating Solar

Science.gov (United States)

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

Understanding barriers and facilitators to the use of Clinical Information Systems for intensive care units and Anesthesia Record Keeping: A rapid ethnography.

Science.gov (United States)

Saleem, Jason J; Plew, William R; Speir, Ross C; Herout, Jennifer; Wilck, Nancy R; Ryan, Dale Marie; Cullen, Theresa A; Scott, Jean M; Beene, Murielle S; Phillips, Toni

2015-07-01

This study evaluated the current use of commercial-off-the-shelf Clinical Information Systems (CIS) for intensive care units (ICUs) and Anesthesia Record Keeping (ARK) for operating rooms and post-anesthesia care recovery settings at three Veterans Affairs Medical Centers (VAMCs). Clinicians and administrative staff use these applications at bedside workstations, in operating rooms, at nursing stations, in physician's rooms, and in other various settings. The intention of a CIS or an ARK system is to facilitate creation of electronic records of data, assessments, and procedures from multiple medical devices. The US Department of Veterans Affairs (VA) Office of the Chief of Nursing Informatics sought to understand usage barriers and facilitators to optimize these systems in the future. Therefore, a human factors study was carried out to observe the CIS and ARK systems in use at three VAMCs in order to identify best practices and suggested improvements to currently implemented CIS and ARK systems. We conducted a rapid ethnographic study of clinical end-users interacting with the CIS and ARK systems in the critical care and anesthesia care areas in each of three geographically distributed VAMCs. Two observers recorded interactions and/or interview responses from 88 CIS and ARK end-users. We coded and sorted into logical categories field notes from 69 shadowed participants. The team transcribed and combined data from key informant interviews with 19 additional participants with the observation data. We then integrated findings across observations into meaningful patterns and abstracted the data into themes, which translated directly to barriers to effective adoption and optimization of the CIS and ARK systems. Effective optimization of the CIS and ARK systems was impeded by: (1) integration issues with other software systems; (2) poor usability; (3) software challenges; (4) hardware challenges; (5) training concerns; (6) unclear roles and lack of coordination among

Dimorphic ovary differentiation in honeybee (Apis mellifera larvae involves caste-specific expression of homologs of ark and buffy cell death genes.

Directory of Open Access Journals (Sweden)

Rodrigo Pires Dallacqua

Full Text Available The establishment of the number of repeated structural units, the ovarioles, in the ovaries is one of the critical events that shape caste polyphenism in social insects. In early postembryonic development, honeybee (Apis mellifera larvae have a pair of ovaries, each one consisting of almost two hundred ovariole primordia. While practically all these ovarioles continue developing in queen-destined larvae, they undergo massive programmed cell death (PCD in worker-destined larvae. So as to gain insight into the molecular basis of this fundamental process in caste differentiation we used quantitative PCR (qPCR and fluorescent in situ hybridization (FISH to investigate the expression of the Amark and Ambuffy genes in the ovaries of the two honeybee castes throughout the fifth larval instar. These are the homologs of ark and buffy Drosophila melanogaster genes, respectively, involved in activating and inhibiting PCD. Caste-specific expression patterns were found during this time-window defining ovariole number. Amark transcript levels were increased when ovariole resorption was intensified in workers, but remained at low levels in queen ovaries. The transcripts were mainly localized at the apical end of all the worker ovarioles, but appeared in only a few queen ovarioles, thus strongly suggesting a function in mediating massive ovariolar cell death in worker larvae. Ambuffy was mainly expressed in the peritoneal sheath cells covering each ovariole. The levels of Ambuffy transcripts increased earlier in the developing ovaries of queens than in workers. Consistent with a protective role against cell death, Ambuffy transcripts were localized in practically all queen ovarioles, but only in few worker ovarioles. The results are indicative of a functional relationship between the expression of evolutionary conserved cell death genes and the morphological events leading to caste-specific ovary differentiation in a social insect.

Solar neutrinos and nonradial solar oscillations

International Nuclear Information System (INIS)

Zatsepin, G.T.; Gavryuseva, E.A.; Kopysov, Yu.S.

1980-01-01

The problem of origin of surface solar oscillations is considered. It is assumed that generation of oscillations is performed by the solar nucleus. The necessary excitation condition for gravitational oscillations of the solar nucleus is a sharp decrease of the oscillation amplitude outside the nucleus, where the nuclear reaction rates are small and only radiation losses are considerable. It is shown that the specific singularities of gravitational wave propagation in solar entrails permit to attain a significant reduction of the oscillation amplitude. The solar entrails can serve as an effective trap for gravitational waves, if the substance of the solar nucleus is close to the state of convectional equilibrium. In order that the g 1 quadrupole mode of the solar nucleus has a period of 2h 40 min and sharply decreases in the solar mantle, it is enough that only the external part of the solar nucleus is close to the state of convectional equilibrium. Closeness of the solar nucleus to the state of convectional equilibrium is an argument in favour of its periodic mixing. Periodic mixing of the solar nucleus can serve as a cause of a low counting rate of solar neutrinos in R.Davis chlorous detector

Concentrating Solar Power Projects - KaXu Solar One | Concentrating Solar

Science.gov (United States)

Power | NREL KaXu Solar One This page provides information on KaXu Solar One, a concentrating solar power (CSP) project, with data organized by background, parcipants and power plant configuration . Status Date: April 14, 2015 Project Overview Project Name: KaXu Solar One Country: South Africa Location

Solar India - 82: national solar energy convention

Energy Technology Data Exchange (ETDEWEB)

1982-01-01

This document is the proceedings of the Solar India - 82 conference, which was held 17-19 December 1982. The papers are organized into functional groupings which include: (1) solar radiation, (2) flat plate solar collectors and solar water heaters, (3) solar concentrators, (4) solar air heaters and dryers, (5) solar ponds and energy storage, (6) solar cookers, (7) solar stills, (8) selective coatings, (9) photovoltaics, (10) space heating and cooling, (11) bio-energy, and (12) miscellaneous papers. The vast majority of the papers describe work carried out in India, the vast majority of the papers also contain relatively readable abstracts.

Solar constant values for estimating solar radiation

International Nuclear Information System (INIS)

Li, Huashan; Lian, Yongwang; Wang, Xianlong; Ma, Weibin; Zhao, Liang

2011-01-01

There are many solar constant values given and adopted by researchers, leading to confusion in estimating solar radiation. In this study, some solar constant values collected from literature for estimating solar radiation with the Angstroem-Prescott correlation are tested in China using the measured data between 1971 and 2000. According to the ranking method based on the t-statistic, a strategy to select the best solar constant value for estimating the monthly average daily global solar radiation with the Angstroem-Prescott correlation is proposed. -- Research highlights: → The effect of the solar constant on estimating solar radiation is investigated. → The investigation covers a diverse range of climate and geography in China. → A strategy to select the best solar constant for estimating radiation is proposed.

76 FR 22143 - Notice of Intent To Accept Proposals, Select One Lessee, and Contract for Hydroelectric Power...

Science.gov (United States)

2011-04-20

..., and any other applicable water-related contracts. 7. Identify the organizational structure planned for... Fryingpan-Arkansas Project (Fry-Ark Project), Colorado AGENCY: Bureau of Reclamation, Interior. ACTION... at Pueblo Dam River Outlet of the Fry-Ark Project, Colorado. Reclamation is considering such...

Solar Energy Innovation Network | Solar Research | NREL

Science.gov (United States)

Energy Innovation Network Solar Energy Innovation Network The Solar Energy Innovation Network grid. Text version The Solar Energy Innovation Network is a collaborative research effort administered (DOE) Solar Energy Technologies Office to develop and demonstrate new ways for solar energy to improve

The Populus ARBORKNOX1 homeodomain transcription factor regulates woody growth through binding to evolutionarily conserved target genes of diverse function

Science.gov (United States)

Lijun Liu; Matthew S. Zinkgraf; H. Earl Petzold; Eric P. Beers; Vladimir Filkov; Andrew Groover

2014-01-01

The class I KNOX homeodomain transcription factor ARBORKNOX1 (ARK1) is a key regulator of vascular cambium maintenance and cell differentiation in Populus. Currently, basic information is lacking concerning the distribution, functional characteristics, and evolution of ARK1 binding in the Populus genome.

PERFORMANCE EVALUATION OF SOLAR COLLECTORS USING A SOLAR SIMULATOR

Directory of Open Access Journals (Sweden)

M. Norhafana

2015-11-01

Full Text Available Solar water heating systems is one of the applications of solar energy. One of the components of a solar water heating system is a solar collector that consists of an absorber. The performance of the solar water heating system depends on the absorber in the solar collector. In countries with unsuitable weather conditions, the indoor testing of solar collectors with the use of a solar simulator is preferred. Thus, this study is conducted to use a multilayered absorber in the solar collector of a solar water heating system as well as to evaluate the performance of the solar collector in terms of useful heat of the multilayered absorber using the multidirectional ability of a solar simulator at several values of solar radiation. It is operated at three variables of solar radiation of 400 W/m2, 550 W/m2 and 700 W/m2 and using three different positions of angles at 0º, 45º and 90º. The results show that the multilayer absorber in the solar collector is only able to best adapt at 45° of solar simulator with different values of radiation intensity. At this angle the maximum values of useful heat and temperature difference are achieved. KEYWORDS: solar water heating system; solar collector; multilayered absorber; solar simulator; solar radiation 

Coupled solar still, solar heater

Energy Technology Data Exchange (ETDEWEB)

Davison, R R; Harris, W B; Moor, D H; Delyannis, A; Delyannis, E [eds.

1976-01-01

Computer simulation of combinations of solar stills and solar heaters indicates the probable economic advantage of such an arrangement in many locations if the size of the heater is optimized relative to that of the still. Experience with various low cost solar heaters is discussed.

Frozen WWII battlefields in High Arctic Greenland

DEFF Research Database (Denmark)

Fog Jensen, Jens

Projektet ’Kampen om Klimaet’ har til formål gennem tværfaglige historiske og arkæologiske undersøgelser at dokumentere Anden Verdens Krigs arkæologiske spor i Nordøstgrønland, samt at analysere disse i et tværfagligt perspektiv...

The solarPACES strategy for the solar thermal breakthrough

International Nuclear Information System (INIS)

Burch, G.D.; Grasse, W.

1997-01-01

IEA(International Energy Agency)/SolarPACES(Solar Power and Chemical Energy systems)represents a world wide coalition for information sharing and collaboration on applications of concentrated solar energy. The current SolarPACES community has built up solar thermal system know-how over 15 years, is operating the three main solar test centres in the world. Its main activities are in the following four fields: solar thermal electric power systems, solar chemistry, solar technology and advanced applications and non-technical activities. The article presents the talk on the strategy of solarPACES given at the International Workshop on applied solar energy held in Tashkent(Uzbekistan) in June 1997. (A.A.D.)

Solar Market Research and Analysis | Solar Research | NREL

Science.gov (United States)

Analysis Solar Market Research and Analysis Through rigorous data collection, analysis, and stakeholder engagement, NREL's Solar Market Research and Analysis efforts further solar technologies' role in solar panels. Key areas for NREL's solar market research and analysis portfolio include the following

PERFORMANCE EVALUATION OF SOLAR COLLECTORS USING A SOLAR SIMULATOR

OpenAIRE

M. Norhafana; Ahmad Faris Ismail; Z. A. A. Majid

2015-01-01

Solar water heating systems is one of the applications of solar energy. One of the components of a solar water heating system is a solar collector that consists of an absorber. The performance of the solar water heating system depends on the absorber in the solar collector. In countries with unsuitable weather conditions, the indoor testing of solar collectors with the use of a solar simulator is preferred. Thus, this study is conducted to use a multilayered absorber in the solar collector of...

Solar building

OpenAIRE

Zhang, Luxin

2014-01-01

In my thesis I describe the utilization of solar energy and solar energy with building integration. In introduction it is also mentioned how the solar building works, trying to make more people understand and accept the solar building. The thesis introduces different types of solar heat collectors. I compared the difference two operation modes of solar water heating system and created examples of solar water system selection. I also introduced other solar building applications. It is conv...

Concentrated solar power generation using solar receivers

Science.gov (United States)

Anderson, Bruce N.; Treece, William Dean; Brown, Dan; Bennhold, Florian; Hilgert, Christoph

2017-08-08

Inventive concentrated solar power systems using solar receivers, and related devices and methods, are generally described. Low pressure solar receivers are provided that function to convert solar radiation energy to thermal energy of a working fluid, e.g., a working fluid of a power generation or thermal storage system. In some embodiments, low pressure solar receivers are provided herein that are useful in conjunction with gas turbine based power generation systems.

A solar neutrino loophole: standard solar models

Energy Technology Data Exchange (ETDEWEB)

Rouse, C A [General Atomic Co., San Diego, Calif. (USA)

1975-11-01

The salient aspects of the existence theorem for a unique solution to a system of linear of nonlinear first-order, ordinary differential equations are given and applied to the equilibrium stellar structure equations. It is shown that values of pressure, temperature, mass and luminosity are needed at one point - and for the sun, the logical point is the solar radius. It is concluded that since standard solar model calculations use split boundary conditions, a solar neutrino loophole still remains: solar model calculations that seek to satisfy the necessary condition for a unique solution to the solar structure equations suggest a solar interior quite different from that deduced in standard models. This, in turn, suggests a theory of formation and solar evolution significantly different from the standard theory.

Hemiuroid trematode sporocysts are undetected by hemocytes of their intermediate host, the ark cockle Anadara trapezia: potential role of surface carbohydrates in successful parasitism.

Science.gov (United States)

Kawasaki, Minami; Delamare-Deboutteville, Jerome; Dang, Cecile; Barnes, Andrew C

2013-12-01

In order to establish a successful relationship with their hosts, parasites must subvert or evade immune defences. Cockle Anadara trapezia and Sydney Rock oyster (SRO) Saccostrea glomerata live in the same location but only ark cockles are infected by sporocysts of hemiuroid trematode. This provides an opportunity to explore differing interactions between the parasite and the immune system of susceptible and refractive hosts. Rapid migration and encapsulation of sporocysts was observed by SRO hemocytes but not by cockle hemocytes. This migration/encapsulation was inhibited by N-acetylglucosamine or N-acetylgalactosamine but not by the other sugars, implicating specific surface carbohydrates in immune detection. Effector responses of hemocytes were investigated in vitro in terms of production of reactive oxygen production (ROS). Hemocytes of both species strongly reacted to Zymosan, but only SRO hemocytes responded to live sporocysts. Neither species' hemocytes produced ROS in the presence of dead/fixed sporocysts, and there was no suppression of Zymosan-induced respiratory burst by sporocysts. This suggests that immune escape is mediated by avoiding encapsulation, perhaps through molecular mimicry. Membrane-shaving with proteases indicated that sporocyst surface proteins are not a key factors in hemocytic detection. Surface carbohydrates of SRO and cockle hemocytes and of sporocysts were profiled with a panel of biotinylated lectins. This revealed substantial differences between cockle and SRO hemocytes, but greater similarity between cockle hemocytes and sporocysts. Results suggest that surface carbohydrates play an integral role in hemocyte immunorecognition and that surface carbohydrate molecular mimicry is a potential strategy for immune evasion in cockles by hemiuroid trematode sporocysts. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Solar Systems

Science.gov (United States)

1979-01-01

The solar collectors shown are elements of domestic solar hot water systems produced by Solar One Ltd., Virginia Beach, Virginia. Design of these systems benefited from technical expertise provided Solar One by NASA's Langley Research Center. The company obtained a NASA technical support package describing the d e sign and operation of solar heating equipment in NASA's Tech House, a demonstration project in which aerospace and commercial building technology are combined in an energy- efficient home. Solar One received further assistance through personal contact with Langley solar experts. The company reports that the technical information provided by NASA influenced Solar One's panel design, its selection of a long-life panel coating which increases solar collection efficiency, and the method adopted for protecting solar collectors from freezing conditions.

Solar electricity and solar fuels

Science.gov (United States)

Spiers, David J.

1989-04-01

The nature of solar radiation and its variation with location is described. The distribution of energy in the solar spectrum places immediate limits on the theoretical efficiency of conversion processes, since practical absorbers cannot convert all wavelengths received to useful energy. The principles of solar energy conversion methods are described. Absorption of solar energy can give rise to direct electrical generation, heating, or chemical change. Electrical generation from sunlight can be achieved by photovoltaic systems directly or by thermal systems which use solar heat to drive a heat engine and generator. The technology used and under research for promising ways of producing electricity or fuel from solar energy is described. Photovoltaic technology is established today for remote area, small power applications, and photovoltaic module sales alone are over 100 million dollars per year at present. The photovoltaic market has grown steadily since the mid-1970's, as prices have fallen continuously. Future energy options are briefly described. The merits of a sustainable energy economy, based on renewable energy resources, including solar energy, are emphasized, as this seems to provide the only hope of eliminating the problems caused by the build-up of atmospheric carbon dioxide, acid rain pollution and nuclear waste disposal. There is no doubt that clean fuels which were derived from solar energy and either did not involve carbon dioxide and used atmospheric carbon dioxide as the source dioxide as the source of carbon would be a worthy ideal. Methods described could one day achieve this.

Solar irridiance variations and solar activity

International Nuclear Information System (INIS)

Willson, R.C.

1982-01-01

A mean value for the 1 AU total solar irradiance of 1368.2 W/m 2 and a downward trend of 0.05% per year were derived from measurements by the Active Cavity Radiometer Irradiance Monitor (ACRIM) experiment on the Solar Maximum Mission during 1980. Distinct temporary solar irradiance decreases associated with solar activity maxima were observed with a series of nine dips from April to October recurring at fairly regular intervals averaging 24 days. The decreases correlate inversely with sunspot area, 2800-MHz flux, and Zurich sunspot number. Dominant periods common to the irradiance and sunspot area power spectra link the irradiance decreases to sunspot flux deficit in solar active regions. Evidence of significant total irradiance modulation by facular flux excess is cited. A persistent radiative cycle of active regions consistent with the ACRIM irradiance results and the morphology of solar active regions was found. The pattern of regularly recurrent active region maxima between April and October suggests an asymmetry in solar activity generation during this period

Solar Training Network and Solar Ready Vets

Energy Technology Data Exchange (ETDEWEB)

Dalstrom, Tenley Ann

2016-09-14

In 2016, the White House announced the Solar Ready Vets program, funded under DOE's SunShot initiative would be administered by The Solar Foundation to connect transitioning military personnel to solar training and employment as they separate from service. This presentation is geared to informing and recruiting employer partners for the Solar Ready Vets program, and the Solar Training Network. It describes the programs, and the benefits to employers that choose to connect to the programs.

Solar Indices - Solar Flares

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

Solar Indices - Solar Ultraviolet

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

Solar Indices - Solar Corona

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

Solar Indices - Solar Irradiance

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

Solar air conditioning. Dresden colloquium; Solare Klimatisierung. Dresdner Kolloquium

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-07-01

Subjects: R + D activities in solar air conditioning; dessicative and evaporative cooling (DEC) - systems and components; Chances of solar air conditioning in Europe; Practical experience with solar-assisted air conditioning; Performance of a solar system at Lissabon; DEC system in the Alsenblock building, Berlin; Does solar air conditioning require specially designed buildings; Performance of solar heated adsorption refrigerators; Low-capacity absacity absorption systems for solar air conditioning. [German] Die Kolloquiumsschrift beinhaltet Unterlagen ueber die abgehandelten Themen. Sie lauten: F and E-Aktivitaeten im Bereich Solare Klimatisierung; SGK(DEC-Technik) - ausgefuehrte Anlagen und deren Komponenten; Chancen der solaren Klimatisierung in Europa; Erfahrungen mit der solarunterstuetzten Klimatisierung; Energieverbrauch und Regelung von SGK-Anlagen; Betriebserfahrungen einer Solaranlage in Lissabon; Realisierung der SGK im Alsenblock Berlin; Erfordert die solare Klimatisierung besondere Gebaeude?; Betriebserfahrungen mit solar beheizten Adsorptionskaeltemaschinen; Absorptionsanlagen kleiner Leistung fuer solare Klimatisierung. (orig.)

Solar charge controller in solar street light

OpenAIRE

Dong, Haibo

2014-01-01

Recently, with the rapid development of scientific technology, the conventional energy cannot meet the requirement of human beings. People are looking for the utilization of renew energy. Solar en-ergy as a new clean energy has attract the eyes of people. The applications of solar energy are popular to human society. Solar street light is a good example. This thesis will focus on a deeper research of the popular and ubiquitous solar street light in China. However, solar charge controll...

The 3-D solar radioastronomy and the structure of the corona and the solar wind. [solar probes of solar activity

Science.gov (United States)

Steinberg, J. L.; Caroubalos, C.

1976-01-01

The mechanism causing solar radio bursts (1 and 111) is examined. It is proposed that a nonthermal energy source is responsible for the bursts; nonthermal energy is converted into electromagnetic energy. The advantages are examined for an out-of-the-ecliptic solar probe mission, which is proposed as a means of stereoscopically viewing solar radio bursts, solar magnetic fields, coronal structure, and the solar wind.

Collecting Solar Energy. Solar Energy Education Project.

Science.gov (United States)

O'Brien, Alexander

This solar energy learning module for use with junior high school students offers a list of activities, a pre-post test, job titles, basic solar energy vocabulary, and diagrams of solar energy collectors and installations. The purpose is to familiarize students with applications of solar energy and titles of jobs where this knowledge could be…

Solar energy

International Nuclear Information System (INIS)

Anon.

1992-01-01

This chapter discusses the role solar energy may have in the energy future of the US. The topics discussed in the chapter include the solar resource, solar architecture including passive solar design and solar collectors, solar-thermal concentrating systems including parabolic troughs and dishes and central receivers, photovoltaic cells including photovoltaic systems for home use, and environmental, health and safety issues

Solar Innovation Infographic | Solar Research | NREL

Science.gov (United States)

Innovation Infographic Solar Innovation Infographic Scientists have been working to harness power from the sun for about 200 years. Over the past 40 years, solar energy technologies have made research developments and industry milestones that helped shape our U.S. solar industry. Infographic Embed

Geometry of solar corona expansion and solar wind parameters

International Nuclear Information System (INIS)

Krajnev, M.B.

1980-01-01

The character of the parameter chanqe of solar wind plasma in the region of the Earth orbit is studied. The main regularities in the parametep behaviour of solar wind (plasma velocity and density) are qualitatively explained in the framework of a model according to which solar corona expansion stronqly differs from radial expansion, that is: the solar wind current lines are focused towards helioequator during the period of low solar activity with gradual transfer to radial expansion during the years of high solar activity. It is shown that the geometry of the solar wind current tubes and its change with the solar activity cycle can not serve an explanation of the observed change of the solar wind parameters

Parameterization models for solar radiation and solar technology applications

Energy Technology Data Exchange (ETDEWEB)

Khalil, Samy A. [National Research Institute of Astronomy and Geophysics, Solar and Space Department, Marsed Street, Helwan, 11421 Cairo (Egypt)

2008-08-15

Solar radiation is very important for the evaluation and wide use of solar renewable energy systems. The development of calibration procedures for broadband solar radiation photometric instrumentation and the improvement of broadband solar radiation measurement accuracy have been done. An improved diffuse sky reference and photometric calibration and characterization software for outdoor pyranometer calibrations are outlined. Parameterizations for direct beam, total hemispherical and diffuse sky radiation and solar radiation technology are briefly reviewed. The uncertainties for various broadband solar radiations of solar energy and atmospheric effects are discussed. The varying responsivities of solar radiation with meteorological, statistical and climatological parameters and possibility atmospheric conditions was examined. (author)

Parameterization models for solar radiation and solar technology applications

International Nuclear Information System (INIS)

Khalil, Samy A.

2008-01-01

Solar radiation is very important for the evaluation and wide use of solar renewable energy systems. The development of calibration procedures for broadband solar radiation photometric instrumentation and the improvement of broadband solar radiation measurement accuracy have been done. An improved diffuse sky reference and photometric calibration and characterization software for outdoor pyranometer calibrations are outlined. Parameterizations for direct beam, total hemispherical and diffuse sky radiation and solar radiation technology are briefly reviewed. The uncertainties for various broadband solar radiations of solar energy and atmospheric effects are discussed. The varying responsivities of solar radiation with meteorological, statistical and climatological parameters and possibility atmospheric conditions was examined

Variation of the solar wind velocity following solar flares

International Nuclear Information System (INIS)

Huang, Y.; Lee, Y.

1975-01-01

By use of the superposed epoch method, changes in the solar wind velocity following solar flares have been investigated by using the solar wind velocity data obtained by Pioneer 6 and 7 and Vela 3, 4, and 5 satellites. A significant increase of the solar wind velocity has been found on the second day following importance 3 solar flares and on the third day following importance 2 solar flares. No significant increase of the solar wind velocity has been found for limb flares. (auth)

Solar Market Research and Analysis Projects | Solar Research | NREL

Science.gov (United States)

Market Research and Analysis Projects Solar Market Research and Analysis Projects Solar market research and analysis efforts at NREL seek to further solar technologies' role in supporting a more . Midscale Commercial Market Solar Analysis NREL experts are providing analysis to expand the midscale solar

Solar energy

Science.gov (United States)

Rapp, D.

1981-01-01

The book opens with a review of the patterns of energy use and resources in the United States, and an exploration of the potential of solar energy to supply some of this energy in the future. This is followed by background material on solar geometry, solar intensities, flat plate collectors, and economics. Detailed attention is then given to a variety of solar units and systems, including domestic hot water systems, space heating systems, solar-assisted heat pumps, intermediate temperature collectors, space heating/cooling systems, concentrating collectors for high temperatures, storage systems, and solar total energy systems. Finally, rights to solar access are discussed.

Solar Combisystems

DEFF Research Database (Denmark)

Thür, Alexander

2006-01-01

This note first introduces what is a solar combisystem, the structure how a solar combisystem is build up and what are criteria’s to evaluate a solar combisystem concept. Further on the main components of a solar combisystem, the main characteristics and possible advantages and disadvantages...... compared to each other are described. It is not the goal of this note to explain the technical details how to design all components of a solar combisystem. This is done during other lectures of the solar course and in other basic courses as well. This note tries to explain how a solar combisystem...

Solar energy

International Nuclear Information System (INIS)

Kruisheer, N.

1992-01-01

In five brief articles product information is given on solar energy applications with special attention to the Netherlands. After an introduction on solar energy availability in the Netherlands the developments in solar boiler techniques are dealt with. Solar water heaters have advantages for the environment, and government subsidies stimulate different uses of such water heaters. Also the developments of solar cells show good prospects, not only for developing countries, but also for the industrialized countries. In brief the developments in solar energy storage and the connection of solar equipment to the grid are discussed. Finally attention is paid to the applications of passive solar energy in the housing construction, the use of transparent thermal insulation and the developments of translucent materials. 18 figs., 18 ills

Golden Rays - July 2017 | Solar Research | Solar Research | NREL

Science.gov (United States)

, subscribe to the Solar Newsletter. SUBSCRIBE Hot Topics Two solar installers secure solar panels on the roof that has the potential to improve the efficiency of solar panels while leveraging existing

Om hugorme, dyrekranier og tordensten

DEFF Research Database (Denmark)

Søvsø, Mette Højmark; Søvsø, Morten; Siggaard, Anna Louise

2016-01-01

Bygningsofre og andre beslægtede fænomener som udtryk for folketro er velkendte fra både arkæologiske og etnologiske undersøgelser i Danmark. Mens mulighederne for nye etnologiske optegnelser ebber ud, giver et voksende arkæologisk materiale til gengæld mulighed for at kaste nyt lys over emnet og...

Solar Special

International Nuclear Information System (INIS)

Van Roekel, A.; Osborne, J.; Schroeter, S.; De Jong, R.; De Saint Jacob, Y.

2009-01-01

Solar power is growing much faster than most policymakers and analysts realise. As costs come down and feed-in tariffs go up across Europe, a number of countries have started in pursuit of market leader Germany. But in Germany criticism is growing of the multi-billion-euro support schemes that keep the solar industry booming. In this section of the magazine several articles are dedicated to developments in solar energy in Europe. The first article is an overview story on the strong growing global market for solar cells, mainly thanks to subsidy schemes. The second article is on the position of foreign companies in the solar market in Italy. Article number three is dedicated to the conditions for solar technology companies to establish themselves in the German state of Saxony. Also the fifth article deals with the development of solar cells in Saxony: scientists, plant manufacturers and module producers in Saxony are working on new technologies that can be used to produce solar electricity cost-effectively. The goal is to bring the price down to match that of conventionally generated electricity within the next few years. The sixth article deals with the the solar power market in Belgium, which may be overheated or 'oversubsidized'. Article seven is on France, which used to be a pioneer in solar technology, but now produces only a fraction of the solar output of market leader Germany. However, new attractive feed-in-tariffs are changing the solar landscape drastically

Solar Indices - Solar Radio Flux

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

Variations in Solar Parameters and Cosmic Rays with Solar Magnetic Polarity

Energy Technology Data Exchange (ETDEWEB)

Oh, S. [Department of Earth Science Education, Chonnam National University, Gwangju, 61186 (Korea, Republic of); Yi, Y., E-mail: suyeonoh@jnu.ac.kr [Department of Astronomy, Space Science and Geology, Chungnam National University, Daejeon, 34134 (Korea, Republic of)

2017-05-01

The sunspot number varies with the 11-year Schwabe cycle, and the solar magnetic polarity reverses every 11 years approximately at the solar maximum. Because of polarity reversal, the difference between odd and even solar cycles is seen in solar activity. In this study, we create the mean solar cycle expressed by phase using the monthly sunspot number for all solar cycles 1–23. We also generate the mean solar cycle for sunspot area, solar radio flux, and cosmic ray flux within the allowance of observational range. The mean solar cycle has one large peak at solar maximum for odd solar cycles and two small peaks for most even solar cycles. The odd and even solar cycles have the statistical difference in value and shape at a confidence level of at least 98%. For solar cycles 19–23, the second peak in the even solar cycle is larger than the first peak. This result is consistent with the frequent solar events during the declining phase after the solar maximum. The difference between odd and even solar cycles can be explained by a combined model of polarity reversal and solar rotation. In the positive/negative polarity, the polar magnetic field introduces angular momentum in the same/opposite direction as/to the solar rotation. Thus the addition/subtraction of angular momentum can increase/decrease the motion of plasma to support the formation of sunspots. Since the polarity reverses at the solar maximum, the opposite phenomenon occurs in the declining phase.

Solar Proton Events in Six Solar Cycles

Science.gov (United States)

Vitaly, Ishkov

Based on materials the catalogs of solar proton events (SPE) in 1955 ‒ 2010 and list SPE for the current 24 solar cycle (SC) are examined confirmed SPE with E> 10 MeV proton flux in excess of 1 proton cm-2 s ster-1 (pfu) from Švestka and Simon’s (1955 - 1969) and 5 volumes Logachev’s (1970 - 2006) Catalogs of SPE. Historically thus it was formed, that the measurements of the proton fluxes began in the epoch “increased” solar activity (SC 18 ‒ 22), and includes transition period of the solar magnetic fields reconstruction from epoch “increased” to the epoch “lowered” solar activity (22 ‒ 23 SC). In current 24 SC ‒ first SC of the incipient epoch of “lowered” SA ‒ SPE realize under the new conditions, to that of previously not observed. As showed a study of five solar cycles with the reliable measurements of E> 10 MeV proton flux in excess of 1 pfu (1964 - 2013): ‒ a quantity of SPEs remained approximately identical in SC 20, 21, somewhat decreased in the initial solar cycle of the solar magnetic fields reconstruction period (22), but it returned to the same quantity in, the base for the period of reconstruction, SC 23. ‒ Into the first 5 years of the each solar cycle development the rate of the proton generation events noticeably increased in 22 cycles of solar activity and returned to the average in cycles 23 and 24. ‒ Extreme solar flare events are achieved, as a rule, in the solar magnetic fields reconstruction period (August - September 1859; June 1991; October ‒ November 2003.), it is confirmed also for SPE: the extreme fluxes of solar protons (S4) except one (August 1972) were occurred in period of perestroika (SC 22 and 23). This can speak, that inside the epochs SA, when the generation of magnetic field in the convective zone works in the steady-state regime, extreme SPE are improbable. ‒ The largest in the fluxes of protons (S3, S4) occur in the complexes of the active regions flare events, where magnetic field more

Implicit-explicit (IMEX) Runge-Kutta methods for non-hydrostatic atmospheric models

Science.gov (United States)

Gardner, David J.; Guerra, Jorge E.; Hamon, François P.; Reynolds, Daniel R.; Ullrich, Paul A.; Woodward, Carol S.

2018-04-01

The efficient simulation of non-hydrostatic atmospheric dynamics requires time integration methods capable of overcoming the explicit stability constraints on time step size arising from acoustic waves. In this work, we investigate various implicit-explicit (IMEX) additive Runge-Kutta (ARK) methods for evolving acoustic waves implicitly to enable larger time step sizes in a global non-hydrostatic atmospheric model. The IMEX formulations considered include horizontally explicit - vertically implicit (HEVI) approaches as well as splittings that treat some horizontal dynamics implicitly. In each case, the impact of solving nonlinear systems in each implicit ARK stage in a linearly implicit fashion is also explored. The accuracy and efficiency of the IMEX splittings, ARK methods, and solver options are evaluated on a gravity wave and baroclinic wave test case. HEVI splittings that treat some vertical dynamics explicitly do not show a benefit in solution quality or run time over the most implicit HEVI formulation. While splittings that implicitly evolve some horizontal dynamics increase the maximum stable step size of a method, the gains are insufficient to overcome the additional cost of solving a globally coupled system. Solving implicit stage systems in a linearly implicit manner limits the solver cost but this is offset by a reduction in step size to achieve the desired accuracy for some methods. Overall, the third-order ARS343 and ARK324 methods performed the best, followed by the second-order ARS232 and ARK232 methods.

Implicit–explicit (IMEX Runge–Kutta methods for non-hydrostatic atmospheric models

Directory of Open Access Journals (Sweden)

D. J. Gardner

2018-04-01

Full Text Available The efficient simulation of non-hydrostatic atmospheric dynamics requires time integration methods capable of overcoming the explicit stability constraints on time step size arising from acoustic waves. In this work, we investigate various implicit–explicit (IMEX additive Runge–Kutta (ARK methods for evolving acoustic waves implicitly to enable larger time step sizes in a global non-hydrostatic atmospheric model. The IMEX formulations considered include horizontally explicit – vertically implicit (HEVI approaches as well as splittings that treat some horizontal dynamics implicitly. In each case, the impact of solving nonlinear systems in each implicit ARK stage in a linearly implicit fashion is also explored.The accuracy and efficiency of the IMEX splittings, ARK methods, and solver options are evaluated on a gravity wave and baroclinic wave test case. HEVI splittings that treat some vertical dynamics explicitly do not show a benefit in solution quality or run time over the most implicit HEVI formulation. While splittings that implicitly evolve some horizontal dynamics increase the maximum stable step size of a method, the gains are insufficient to overcome the additional cost of solving a globally coupled system. Solving implicit stage systems in a linearly implicit manner limits the solver cost but this is offset by a reduction in step size to achieve the desired accuracy for some methods. Overall, the third-order ARS343 and ARK324 methods performed the best, followed by the second-order ARS232 and ARK232 methods.

Alveolar ridge keratosis - a retrospective clinicopathological study

Science.gov (United States)

2013-01-01

Background Alveolar ridge keratosis (ARK) is a distinct, benign clinicopathological entity, characterized by a hyperkeratotic plaque or patch that occurs on the alveolar edentulous ridge or on the retromolar trigone, considered to be caused by chronic frictional trauma. The aim of this retrospective study is to present the clinicopathological features of 23 consecutive cases of ARK. Material and methods The 23 biopsy samples of ARK were selected and pathological features were revised (keratosis, acanthosis, surface architecture, and inflammation). Factors such as the patient’s gender, age, anatomical location, tobacco and alcohol use were analyzed. Results Sixteen out of the 23 cases studied were men and 7 women with a mean age of 55.05 (age ranged from 17 to 88 years). Thirteen cases had a history of tobacco habit, amongst whom, 4 also presented alcohol consumption. All the cases presented only unilateral lesions. Nineteen cases involved the retromolar trigone while 4 cases involved edentulous alveolar ridges. When observed microscopically, the lesions were mainly characterized by moderate to important hyperorthokeratosis. Inflammation was scanty or absent. In four of the cases, the presence of melanin pigment in the superficial corium or in the cytoplasm of macrophages was detected. None of the cases showed any features of dysplasia. Conclusion Our results reveal that ARK is a benign lesion. However, the high prevalence of smokers amongst the patients might suggest that some potentially malignant disorders such as tobacco associated leukoplakia may clinically mimic ARK. PMID:23587097

Alveolar ridge keratosis--a retrospective clinicopathological study.

Science.gov (United States)

Bellato, Lorenzo; Martinelli-Kläy, Carla P; Martinelli, Celso R; Lombardi, Tommaso

2013-04-16

Alveolar ridge keratosis (ARK) is a distinct, benign clinicopathological entity, characterized by a hyperkeratotic plaque or patch that occurs on the alveolar edentulous ridge or on the retromolar trigone, considered to be caused by chronic frictional trauma. The aim of this retrospective study is to present the clinicopathological features of 23 consecutive cases of ARK. The 23 biopsy samples of ARK were selected and pathological features were revised (keratosis, acanthosis, surface architecture, and inflammation). Factors such as the patient's gender, age, anatomical location, tobacco and alcohol use were analyzed. Sixteen out of the 23 cases studied were men and 7 women with a mean age of 55.05 (age ranged from 17 to 88 years). Thirteen cases had a history of tobacco habit, amongst whom, 4 also presented alcohol consumption. All the cases presented only unilateral lesions. Nineteen cases involved the retromolar trigone while 4 cases involved edentulous alveolar ridges. When observed microscopically, the lesions were mainly characterized by moderate to important hyperorthokeratosis. Inflammation was scanty or absent. In four of the cases, the presence of melanin pigment in the superficial corium or in the cytoplasm of macrophages was detected. None of the cases showed any features of dysplasia. Our results reveal that ARK is a benign lesion. However, the high prevalence of smokers amongst the patients might suggest that some potentially malignant disorders such as tobacco associated leukoplakia may clinically mimic ARK.

Early solar physics

CERN Document Server

Meadows, A J

1970-01-01

Early Solar Physics reviews developments in solar physics, particularly the advent of solar spectroscopy and the discovery of relationships between the various layers of the solar atmosphere and between the different forms of solar activity. Topics covered include solar observations during 1843; chemical analysis of the solar atmosphere; the spectrum of a solar prominence; and the solar eclipse of December 12, 1871. Spectroscopic observations of the sun are also presented. This book is comprised of 30 chapters and begins with an overview of ideas about the sun in the mid-nineteenth century, fo

SolarChill - a solar PV refrigerator without battery

Energy Technology Data Exchange (ETDEWEB)

Pedersen, P.H.; Poulsen, S.; Katic, I. [Danish Technological Inst., Taastrup (Denmark)

2004-07-01

A solar powered refrigerator (SolarChill) has been developed in an international project involving Greenpeace International, GTZ, UNICEF, UNEP, WHO, industrial partners and Danish Technological Institute. The refrigerator is able to operate directly on solar PV panels, without battery or additional electronics, and is therefore suitable for locations where little maintenance and reliable operation is mandatory. The main objective of the SolarChill Project is to help deliver vaccines and refrigeration to the rural poor. To achieve this objective, the SolarChill Project developed - and plans to make freely available a versatile refrigeration technology that is environmentally sound, technologically reliable, and affordable. SolarChill does not use any fluorocarbons in its cooling system or in the insulation. For domestic and small business applications, another type of solar refrigerator is under development. This is an upright type, suitable for cool storage of food and beverages in areas where grid power is non-existent or unstable. The market potential for this type is thus present in industrialised countries as well as in countries under development. The unique feature of SolarChill is that energy is stored in ice instead of in batteries. An ice compartment keeps the cabinet at desired temperatures during the night. The paper describes the product development, possible SolarChill applications and experience with the two types of solar refrigerators, as well as results from the laboratory and field test. (orig.)

SOLAR-ISS: A new reference spectrum based on SOLAR/SOLSPEC observations

Science.gov (United States)

Meftah, M.; Damé, L.; Bolsée, D.; Hauchecorne, A.; Pereira, N.; Sluse, D.; Cessateur, G.; Irbah, A.; Bureau, J.; Weber, M.; Bramstedt, K.; Hilbig, T.; Thiéblemont, R.; Marchand, M.; Lefèvre, F.; Sarkissian, A.; Bekki, S.

2018-03-01

Context. Since April 5, 2008 and up to February 15, 2017, the SOLar SPECtrometer (SOLSPEC) instrument of the SOLAR payload on board the International Space Station (ISS) has performed accurate measurements of solar spectral irradiance (SSI) from the middle ultraviolet to the infrared (165 to 3088 nm). These measurements are of primary importance for a better understanding of solar physics and the impact of solar variability on climate. In particular, a new reference solar spectrum (SOLAR-ISS) is established in April 2008 during the solar minima of cycles 23-24 thanks to revised engineering corrections, improved calibrations, and advanced procedures to account for thermal and aging corrections of the SOLAR/SOLSPEC instrument. Aims: The main objective of this article is to present a new high-resolution solar spectrum with a mean absolute uncertainty of 1.26% at 1σ from 165 to 3000 nm. This solar spectrum is based on solar observations of the SOLAR/SOLSPEC space-based instrument. Methods: The SOLAR/SOLSPEC instrument consists of three separate double monochromators that use concave holographic gratings to cover the middle ultraviolet (UV), visible (VIS), and infrared (IR) domains. Our best ultraviolet, visible, and infrared spectra are merged into a single absolute solar spectrum covering the 165-3000 nm domain. The resulting solar spectrum has a spectral resolution varying between 0.6 and 9.5 nm in the 165-3000 nm wavelength range. We build a new solar reference spectrum (SOLAR-ISS) by constraining existing high-resolution spectra to SOLAR/SOLSPEC observed spectrum. For that purpose, we account for the difference of resolution between the two spectra using the SOLAR/SOLSPEC instrumental slit functions. Results: Using SOLAR/SOLSPEC data, a new solar spectrum covering the 165-3000 nm wavelength range is built and is representative of the 2008 solar minimum. It has a resolution better than 0.1 nm below 1000 nm and 1 nm in the 1000-3000 nm wavelength range. The new

Solar Thermal Energy; Energia Solar Termica

Energy Technology Data Exchange (ETDEWEB)

Perez-Martinez, M; Cuesta-Santianes, M J; Cabrera Jimenez, J A

2008-07-01

Approximately, 50 % of worldwide primary energy consumption is done in the form of heat in applications with a temperature lower than 250 degree centigree (low-medium temperature heat). These data clearly demonstrate the great potential of solar thermal energy to substitute conventional fossil fuels, which are becoming more expensive and are responsible for global warming. Low-medium temperature solar thermal energy is mainly used to obtain domestic hot water and provide space heating. Active solar thermal systems are those related to the use of solar thermal collectors. This study is dealing with low temperature solar thermal applications, mainly focusing on active solar thermal systems. This kind of systems has been extensively growing worldwide during the last years. At the end of 2006, the collector capacity in operation worldwide equalled 127.8 GWth. The technology is considered to be already developed and actions should be aimed at favouring a greater market penetration: diffusion, financial support, regulations establishment, etc. China and USA are the leading countries with a technology based on evacuated tube collectors and unglazed collectors, respectively. The rest of the world markets are dominated by the flat glazed collectors technology. (Author) 15 refs.

Solar cycle distribution of strong solar proton events and the related solar-terrestrial phenomena

Science.gov (United States)

Le, Guiming; Yang, Xingxing; Ding, Liuguang; Liu, Yonghua; Lu, Yangping; Chen, Minhao

2014-08-01

We investigated the solar cycle distribution of strong solar proton events (SPEs, peak flux ≥1000 pfu) and the solar-terrestrial phenomena associated with the strong SPEs during solar cycles 21-23. The results show that 37 strong SPEs were registered over this period of time, where 20 strong SPEs were originated from the super active regions (SARs) and 28 strong SPEs were accompanied by the X-class flares. Most strong SPEs were not associated with the ground level enhancement (GLE) event. Most strong SPEs occurred in the descending phases of the solar cycles. The weaker the solar cycle, the higher the proportion of strong SPES occurred in the descending phase of the cycle. The number of the strong SPEs that occurred within a solar cycle is poorly associated with the solar cycle size. The intensity of the SPEs is highly dependent of the location of their source regions, with the super SPEs (≥20000 pfu) distributed around solar disk center. A super SPE was always accompanied by a fast shock driven by the associated coronal mass ejection and a great geomagnetic storm. The source location of strongest GLE event is distributed in the well-connected region. The SPEs associated with super GLE events (peak increase rate ≥100%) which have their peak flux much lower than 10000 pfu were not accompanied by an intense geomagnetic storm.

SOLAR SOURCES OF 3He-RICH SOLAR ENERGETIC PARTICLE EVENTS IN SOLAR CYCLE 24

International Nuclear Information System (INIS)

Nitta, Nariaki V.; Mason, Glenn M.; Wang, Linghua; Cohen, Christina M. S.; Wiedenbeck, Mark E.

2015-01-01

Using high-cadence EUV images obtained by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory, we investigate the solar sources of 26 3 He-rich solar energetic particle events at ≲1 MeV nucleon −1 that were well-observed by the Advanced Composition Explorer during solar cycle 24. Identification of the solar sources is based on the association of 3 He-rich events with type III radio bursts and electron events as observed by Wind. The source locations are further verified in EUV images from the Solar and Terrestrial Relations Observatory, which provides information on solar activities in the regions not visible from the Earth. Based on AIA observations, 3 He-rich events are not only associated with coronal jets as emphasized in solar cycle 23 studies, but also with more spatially extended eruptions. The properties of the 3 He-rich events do not appear to be strongly correlated with those of the source regions. As in the previous studies, the magnetic connection between the source region and the observer is not always reproduced adequately by the simple potential field source surface model combined with the Parker spiral. Instead, we find a broad longitudinal distribution of the source regions extending well beyond the west limb, with the longitude deviating significantly from that expected from the observed solar wind speed

A High Rated Solar Water Distillation Unit for Solar Homes

Directory of Open Access Journals (Sweden)

Abhishek Saxena

2016-01-01

Full Text Available India is presently focusing on complete utilization of solar energy and saving fossil fuels, which are limited. Various solar energy systems like solar cookers, solar water heaters, solar lanterns, solar PV lights, and solar lamps are continuously availing by the people of India at a low cost and on good subsidies. Apart from this, India is a solar energy promising country with a good number of solar homes (carrying solar energy systems in its various locations. The present paper focuses on a unique combination of solar dish cooker (SDC and solar water heater (SWH to produce distilled water with a high distillate and a high daily productivity. The procedure has been discussed on the basis of experimental testing to produce distilled water by combining an evacuated type SWH and a SDC. Experimentation has been carried out in MIT, Moradabad (longitude, 28.83°N, and latitude, 78.78°E by developing the same experimental setup on behalf of solar homes. The daily productivity of distilled water was found around 3.66 litres per day in full sunshine hours for an approximated pH value of 7.7 and a ppm value of 21. The payback period (PBP has been estimated around 1.16 years of the present system.

Midscale Commercial Solar Market | Solar Research | NREL

Science.gov (United States)

States To help prospective solar customers understand and use the policies of their state for midsized Customers, which equips prospective solar customers with the tools necessary to understand and use the solar corporate customers (Alabama Power's Renewable Procurement Program), and a company with approval to sell

The Solar Energy Trifecta: Solar + Storage + Net Metering | State, Local,

Science.gov (United States)

and Tribal Governments | NREL The Solar Energy Trifecta: Solar + Storage + Net Metering The Solar Energy Trifecta: Solar + Storage + Net Metering February 12, 2018 by Benjamin Mow Massachusetts (DPU) seeking an advisory ruling on the eligibility of pairing solar-plus-storage systems with current

DIY Solar Market Analysis Webinar Series: Solar Resource and Technical

Science.gov (United States)

Series: Solar Resource and Technical Potential DIY Solar Market Analysis Webinar Series: Solar Resource and Technical Potential Wednesday, June 11, 2014 As part of a Do-It-Yourself Solar Market Analysis Potential | State, Local, and Tribal Governments | NREL DIY Solar Market Analysis Webinar

Solar Sailing

Science.gov (United States)

Johnson, Les

2009-01-01

Solar sailing is a topic of growing technical and popular interest. Solar sail propulsion will make space exploration more affordable and offer access to destinations within (and beyond) the solar system that are currently beyond our technical reach. The lecture will describe solar sails, how they work, and what they will be used for in the exploration of space. It will include a discussion of current plans for solar sails and how advanced technology, such as nanotechnology, might enhance their performance. Much has been accomplished recently to make solar sail technology very close to becoming an engineering reality and it will soon be used by the world s space agencies in the exploration of the solar system and beyond. The first part of the lecture will summarize state-of-the-art space propulsion systems and technologies. Though these other technologies are the key to any deep space exploration by humans, robots, or both, solar-sail propulsion will make space exploration more affordable and offer access to distant and difficult destinations. The second part of the lecture will describe the fundamentals of space solar sail propulsion and will describe the near-, mid- and far-term missions that might use solar sails as a propulsion system. The third part of the lecture will describe solar sail technology and the construction of current and future sailcraft, including the work of both government and private space organizations.

Preliminary design package for solar collector and solar pump

Science.gov (United States)

1978-01-01

A solar-operated pump using an existing solar collector, for use on solar heating and cooling and hot water systems is described. Preliminary design criteria of the collector and solar-powered pump is given including: design drawings, verification plans, and hazard analysis.

Solar shading how to integrate solar shading in sustainable buildings

CERN Document Server

Dolmans, Dick; Dutoo, Gonzague; Hall, Anders; Seppänen, Olli

2010-01-01

Solar Shading Guidebook gives a solid background on the physics of solar radiation and its behaviour in window with solar shading systems. Major focus of the Guidebook is on the effect of solar shading in the use of energy for cooling, heating and lighting. The book gives also practical guidance for selection, installation and operation of solar shading as well as future trends in integration of HVAC-systems with solar control.

Performances of solar water pumping station with solar tracker

International Nuclear Information System (INIS)

Buniatyan, V.V.; Vardanyan, A.A.

2011-01-01

For the solar water pumping stations ? solar tracking system with phototransistor is developed. On the basis of the experimental investigations the utility and efficiency of the PV water pumping station with solar tracker under different conditions of varying solar radiation in Armenia is shown

Zubara

DEFF Research Database (Denmark)

Thuesen, Ingolf; Walmsley, Alan George

2010-01-01

Præsentation af projektet, Qatar Islamic Archaeology and Heritage, og de arkæologiske undersøgelser af Al Zubarah, en by fra 17-tallet. Emiratet Qatar er ét af verdens rigeste lande på gas og olie. I 2009 blev der iværksat et stort arkæologisk projekt, som Københavns Universitet er blevet inviter...

Solar Energy.

Science.gov (United States)

Eaton, William W.

Presented is the utilization of solar radiation as an energy resource principally for the production of electricity. Included are discussions of solar thermal conversion, photovoltic conversion, wind energy, and energy from ocean temperature differences. Future solar energy plans, the role of solar energy in plant and fossil fuel production, and…

Solar Energy Systems

Science.gov (United States)

1984-01-01

Calibrated in kilowatt hours per square meter, the solar counter produced by Dodge Products, Inc. provides a numerical count of the solar energy that has accumulated on a surface. Solar energy sensing, measuring and recording devices in corporate solar cell technology developed by Lewis Research Center. Customers for their various devices include architects, engineers and others engaged in construction and operation of solar energy facilities; manufacturers of solar systems or solar related products, such as glare reducing windows; and solar energy planners in federal and state government agencies.

Solar energy: photovoltaics

International Nuclear Information System (INIS)

Goetzberger, A.; Voss, B.; Knobloch, J.

1994-01-01

This textbooks covers the following topics: foundations of photovoltaics, solar energy, P-N junctions, physics of solar cells, high-efficiency solar cells, technology of Si solar cells, other solar cells, photovoltaic applications. (orig.)

Solar Adaptive Optics

Directory of Open Access Journals (Sweden)

Thomas R. Rimmele

2011-06-01

Full Text Available Adaptive optics (AO has become an indispensable tool at ground-based solar telescopes. AO enables the ground-based observer to overcome the adverse effects of atmospheric seeing and obtain diffraction limited observations. Over the last decade adaptive optics systems have been deployed at major ground-based solar telescopes and revitalized ground-based solar astronomy. The relatively small aperture of solar telescopes and the bright source make solar AO possible for visible wavelengths where the majority of solar observations are still performed. Solar AO systems enable diffraction limited observations of the Sun for a significant fraction of the available observing time at ground-based solar telescopes, which often have a larger aperture than equivalent space based observatories, such as HINODE. New ground breaking scientific results have been achieved with solar adaptive optics and this trend continues. New large aperture telescopes are currently being deployed or are under construction. With the aid of solar AO these telescopes will obtain observations of the highly structured and dynamic solar atmosphere with unprecedented resolution. This paper reviews solar adaptive optics techniques and summarizes the recent progress in the field of solar adaptive optics. An outlook to future solar AO developments, including a discussion of Multi-Conjugate AO (MCAO and Ground-Layer AO (GLAO will be given.

Solar radiophysics

International Nuclear Information System (INIS)

McLean, D.J.; Labrum, N.R.

1985-01-01

This book treats all aspects of solar radioastronomy at metre wavelengths, particularly work carried out on the Australian radioheliograph at Culgoora, with which most of the authors have been associated in one way or another. After an introductory section on historical aspects, the solar atmosphere, solar flares, and coronal radio emission, the book deals with instrumentation, theory, and details of observations and interpretations of the various aspects of metrewave solar radioastronomy, including burst types, solar storms, and the quiet sun. (U.K.)

Nanostructured Solar Irradiation Control Materials for Solar Energy Conversion

Science.gov (United States)

Kang, Jinho; Marshall, I. A.; Torrico, M. N.; Taylor, C. R.; Ely, Jeffry; Henderson, Angel Z.; Kim, J.-W.; Sauti, G.; Gibbons, L. J.; Park, C.;

Deciphering Solar Magnetic Activity: Spotting Solar Cycle 25

Energy Technology Data Exchange (ETDEWEB)

McIntosh, Scott W. [High Altitude Observatory, National Center for Atmospheric Research, Boulder, CO (United States); Leamon, Robert J., E-mail: mscott@ucar.edu [Department of Astronomy, University of Maryland, College Park, MD (United States)

2017-06-26

We present observational signatures of solar cycle 25 onset. Those signatures are visibly following a migratory path from high to low latitudes. They had starting points that are asymmetrically offset in each hemisphere at times that are 21–22 years after the corresponding, same polarity, activity bands of solar cycle 23 started their migration. Those bands define the so-called “extended solar cycle.” The four magnetic bands currently present in the system are approaching a mutually cancelling configuration, and solar minimum conditions are imminent. Further, using a tuned analysis of the daily band latitude-time diagnostics, we are able to utilize the longitudinal wave number (m = 1) variation in the data to more clearly reveal the presence of the solar cycle 25 bands. This clarification illustrates that prevalently active longitudes (different in each hemisphere) exist at mid-latitudes presently, lasting many solar rotations, that can be used for detailed study over the next several years with instruments like the Spectrograph on IRIS, the Spectropolarimeter on Hinode, and, when they come online, similar instruments on the Daniel K. Inouye Solar Telescope (DKIST) as we watch those bands evolve following the cancellation of the solar cycle 24 activity bands at the equator late in 2019.

Photovoltaic solar concentrator

Science.gov (United States)

Nielson, Gregory N.; Cruz-Campa, Jose Luis; Okandan, Murat; Resnick, Paul J.; Sanchez, Carlos Anthony; Clews, Peggy J.; Gupta, Vipin P.

2015-09-08

A process including forming a photovoltaic solar cell on a substrate, the photovoltaic solar cell comprising an anchor positioned between the photovoltaic solar cell and the substrate to suspend the photovoltaic solar cell from the substrate. A surface of the photovoltaic solar cell opposite the substrate is attached to a receiving substrate. The receiving substrate may be bonded to the photovoltaic solar cell using an adhesive force or a metal connecting member. The photovoltaic solar cell is then detached from the substrate by lifting the receiving substrate having the photovoltaic solar cell attached thereto and severing the anchor connecting the photovoltaic solar cell to the substrate. Depending upon the type of receiving substrate used, the photovoltaic solar cell may be removed from the receiving substrate or remain on the receiving substrate for use in the final product.

Solarbundesliga (Solar League) and SolarLokal. Competition and campaign for communities

Energy Technology Data Exchange (ETDEWEB)

Vollmer, C. [Deutsche Umwelthilfe e.V., Radolfzell (Germany)

2006-07-01

Summary: Currently more solar power plants are built in Germany than ever before. Citizens, farmers, companies, initiatives and local authorities are participating. Solarbundesliga (Solar League), launched in April 2001, offers a forum for these solar minded actors. It ensures that the local commitment of these actors is known all over Germany and in doing so awakens the competitive drive in many people. The Solarbundesliga is organised by Deutsche Umwelthilfe and the specialist journal Solarthemen. It is a very good instrument to show the outcome of the solar energy supply at the local level in media friendly means. The image campaign SolarLokal of the Deutsche Umwelthilfe and SolarWorld, one of the biggest solar companies worldwide, is a very good approach for municipalities to inform their citizens about the benefits of solar energy. According to a recent opinion poll, SolarLokal contributes to an increase in solar current plants in the participating cities and towns. Additionally, it brings craftspeople having experience in installing solar power plants and interested citizens together. So, SolarLokal provides incentives to the local economy. The idea of SolarLokal is transferable to other countries. In January 2006 the partner campaign IsIaSolar was started in Teneriffa. (orig.)

Solar Adaptive Optics.

Science.gov (United States)

Rimmele, Thomas R; Marino, Jose

Adaptive optics (AO) has become an indispensable tool at ground-based solar telescopes. AO enables the ground-based observer to overcome the adverse effects of atmospheric seeing and obtain diffraction limited observations. Over the last decade adaptive optics systems have been deployed at major ground-based solar telescopes and revitalized ground-based solar astronomy. The relatively small aperture of solar telescopes and the bright source make solar AO possible for visible wavelengths where the majority of solar observations are still performed. Solar AO systems enable diffraction limited observations of the Sun for a significant fraction of the available observing time at ground-based solar telescopes, which often have a larger aperture than equivalent space based observatories, such as HINODE. New ground breaking scientific results have been achieved with solar adaptive optics and this trend continues. New large aperture telescopes are currently being deployed or are under construction. With the aid of solar AO these telescopes will obtain observations of the highly structured and dynamic solar atmosphere with unprecedented resolution. This paper reviews solar adaptive optics techniques and summarizes the recent progress in the field of solar adaptive optics. An outlook to future solar AO developments, including a discussion of Multi-Conjugate AO (MCAO) and Ground-Layer AO (GLAO) will be given. Supplementary material is available for this article at 10.12942/lrsp-2011-2.

Monitoring of the solar activity and solar energetic particles

International Nuclear Information System (INIS)

Akioka, Maki; Kubo, Yuki; Nagatsuma, Tsutomu; Ohtaka, Kazuhiro

2009-01-01

Solar activity is the source of various space weather phenomena in geospace and deep space. Solar X-ray radiation in flare, energetic particles, coronal mass ejection (CME) can cause various kind of disturbance near earth space. Therefore, detailed monitoring of the solar activity and its propagation in the interplanetary space is essential task for space weather. For example, solar energetic particle which sometimes affect spacecraft operation and manned space flight, is considered to be produced by solar flares and travelling shockwave caused by flares and CME. The research and development of monitoring technique and system for various solar activity has been an important topic of space weather forecast program in NICT. In this article, we will introduce the real time data acquisitions of STEREO and optical and radio observations of the Sun at Hiraiso Solar Observatory. (author)

Solar Newsletter | Solar Research | NREL

Science.gov (United States)

more about work by this consortium, which crosses national laboratories, on new materials and designs information on NREL's research and development of solar technologies. To receive new issues by email prize, focused on solar energy technologies, and will release the prize rules and open registration

Photovoltaic. Solar thermal. Solar thermal electricity

International Nuclear Information System (INIS)

2009-01-01

The year 2008 was excellent for solar energy in the European Union. The growth of the installed capacity for photovoltaic was +159% (it means +4747.018 MW) to reach 9689.952 MW and that for solar thermal was +51.5% (it means +3172.5 MW) to reach 19982.7 MW. Worldwide concentrated solar thermal capacity stood at 679 MW in 2009, while this figure may seem low, the sector has a promising future ahead of it. (A.C.)

Solar opacities constrained by solar neutrinos and solar oscillations

International Nuclear Information System (INIS)

Cox, A.N.

1989-01-01

This review discusses the current situation for opacities at the solar center, the solar surface, and for the few million kelvin temperatures that occur below the convection zone. The solar center conditions are important because they are crucial for the neutrino production, which continues to be predicted about 4 times that observed. The main extinction effects there are free-free photon absorption in the electric fields of the hydrogen, helium and the CNO atoms, free electron scattering of photons, and the bound-free and bound-bound absorption of photons by iron atoms with two electrons in the 1s bound level. An assumption that the iron is condensed-out below the convection zone, and the opacity in the central regions is thereby reduced, results in about a 25 percent reduction in the central opacity but only a 5 percent reduction at the base of the convection zone. Furthermore, the p-mode solar oscillations are changed with this assumption, and do not fit the observed ones as well as for standard models. A discussion of the large effective opacity reduction by weakly interacting massive particles also results in poor agreement with observed p-mode oscillation frequencies. The much larger opacities for the solar surface layers from the Los Alamos Astrophysical Opacity Library instead of the widely used Cox and Tabor values show small improvements in oscillation frequency predictions, but the largest effect is in the discussion of p-mode stability. Solar oscillation frequencies can serve as an opacity experiment for the temperatures and densities, respectively, of a few million kelvin and between 0.1 and 10 g/cm 3 . Current oscillation frequency calculations indicate that possibly the Opacity Library values need an increase of typically 15 percent just at the bottom of the convection zone at 3 x 10 6 K. 41 refs., 15 figs., 1 tab

3D Visualization of Solar Data: Preparing for Solar Orbiter and Parker Solar Probe

Science.gov (United States)

Mueller, D.; Nicula, B.; Felix, S.; Verstringe, F.; Bourgoignie, B.; Csillaghy, A.; Berghmans, D.; Jiggens, P.; Ireland, J.; Fleck, B.

2017-12-01

Solar Orbiter and Parker Solar Probe will focus on exploring the linkage between the Sun and the heliosphere. These new missions will collect unique data that will allow us to study, e.g., the coupling between macroscopic physical processes to those on kinetic scales, the generation of solar energetic particles and their propagation into the heliosphere and the origin and acceleration of solar wind plasma. Combined with the several petabytes of data from NASA's Solar Dynamics Observatory, the scientific community will soon have access to multi­dimensional remote-sensing and complex in-situ observations from different vantage points, complemented by petabytes of simulation data. Answering overarching science questions like "How do solar transients drive heliospheric variability and space weather?" will only be possible if the community has the necessary tools at hand. In this contribution, we will present recent progress in visualizing the Sun and its magnetic field in 3D using the open-source JHelioviewer framework, which is part of the ESA/NASA Helioviewer Project.

Calculating the diffuse solar radiation in regions without solar radiation measurements

International Nuclear Information System (INIS)

Li, Huashan; Bu, Xianbiao; Long, Zhen; Zhao, Liang; Ma, Weibin

2012-01-01

Correlations for calculating diffuse solar radiation can be classified into models with global solar radiation (H-based method) and without it (Non-H method). The objective of the present study is to compare the performance of H-based and Non-H methods for calculating the diffuse solar radiation in regions without solar radiation measurements. The comparison is carried out at eight meteorological stations in China focusing on the monthly average daily diffuse solar radiation. Based on statistical error tests, the results show that the Non-H method that includes other readily available meteorological elements gives better estimates. Therefore, it can be concluded that the Non-H method is more appropriate than the H-based one for calculating the diffuse solar radiation in regions without solar radiation measurements. -- Highlights: ► Methods for calculating diffuse solar radiation in regions without solar radiation measurements are investigated. ► Diffuse solar radiation models can be classified into two groups according to global solar radiation. ► Two approaches are compared at the eight meteorological stations in China. ► The method without global solar radiation is recommended.

Solar homebuilders program: getting builders to build solar

Energy Technology Data Exchange (ETDEWEB)

Parkin, B.; Allen, D.

1981-01-01

The homebuilding industry can open the way to wide-scale residential use of solar energy. Under the Northwest Power Act, the Department of Energy's Bonneville Power Administration, Western Solar Utilization Network and the Solar Energy Research Institute are working together with the Home Builders Association of Metropolitan Portland and the Portland chapter of the American Institute of Architects on a program that will affect 7 cities in the Pacific Northwest. Modeled after the successful Denver Metro Homebuilders Program, the project is being implemented in 3 cities in 1981 and three additional cities in 1982. In each of the 7 cities builders and developers will be provided with design, performance monitoring and marketing assistance for constructing passive solar prototypes. The result is ten passive solar homes of superior design and of an affordable price in each city. The secondary result of this program is expected to be a total of 2700 solar homes produced outside the program by builders from 1981-1985. Builders influenced to build passive solar homes outside the program could result in as many as 500,000 homes produced by the year 2000.

Estimation of monthly solar radiation distribution for solar energy system analysis

International Nuclear Information System (INIS)

Coskun, C.; Oktay, Z.; Dincer, I.

2011-01-01

The concept of probability density frequency, which is successfully used for analyses of wind speed and outdoor temperature distributions, is now modified and proposed for estimating solar radiation distributions for design and analysis of solar energy systems. In this study, global solar radiation distribution is comprehensively analyzed for photovoltaic (PV) panel and thermal collector systems. In this regard, a case study is conducted with actual global solar irradiation data of the last 15 years recorded by the Turkish State Meteorological Service. It is found that intensity of global solar irradiance greatly affects energy and exergy efficiencies and hence the performance of collectors. -- Research highlights: → The first study to apply global solar radiation distribution in solar system analyzes. → The first study showing global solar radiation distribution as a parameter of the solar irradiance intensity. → Time probability intensity frequency and probability power distribution do not have similar distribution patterns for each month. → There is no relation between the distribution of annual time lapse and solar energy with the intensity of solar irradiance.

Principles of solar engineering

CERN Document Server

Goswami, D Yogi

2015-01-01

Introduction to Solar Energy ConversionGlobal Energy Needs and ResourcesSolar EnergyEnergy StorageEconomics of Solar SystemsSummary of RE ResourcesForecast of Future Energy MixReferencesFundamentals of Solar RadiationThe Physics of the Sun and Its Energy TransportThermal Radiation FundamentalsSun-Earth Geometric RelationshipSolar RadiationEstimation of Terrestrial Solar RadiationModels Based on Long-Term Measured Horizontal Solar RadiationMeasurement of Solar RadiationSolar Radiation Mapping Using Satellite DataReferencesSuggested ReadingsSolar Thermal CollectorsRadiative Properties and Characteristics of MaterialsFlat-Plate CollectorsTubular Solar Energy CollectorsExperimental Testing of CollectorsConcentrating Solar CollectorsParabolic Trough ConcentratorCompound-Curvature Solar ConcentratorsCentral Receiver CollectorFresnel Reflectors and LensesSolar Concentrator SummaryReferencesSuggested ReadingThermal Energy Storage and TransportThermal Energy StorageTypes of TESDesign of Storage SystemEnergy Transport ...

Solar Plus: A Holistic Approach to Distributed Solar PV

Energy Technology Data Exchange (ETDEWEB)

O' Shaughnessy, Eric [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ardani, Kristen [National Renewable Energy Lab. (NREL), Golden, CO (United States); Cutler, Dylan [National Renewable Energy Lab. (NREL), Golden, CO (United States); Margolis, Robert [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2017-05-25

Solar 'plus' refers to an emerging approach to distributed solar photovoltaic (PV) deployment that uses energy storage and controllable devices to optimize customer economics. The solar plus approach increases customer system value through technologies such as electric batteries, smart domestic water heaters, smart air-conditioner (AC) units, and electric vehicles We use an NREL optimization model to explore the customer-side economics of solar plus under various utility rate structures and net metering rates. We explore optimal solar plus applications in five case studies with different net metering rates and rate structures. The model deploys different configurations of PV, batteries, smart domestic water heaters, and smart AC units in response to different rate structures and customer load profiles. The results indicate that solar plus improves the customer economics of PV and may mitigate some of the negative impacts of evolving rate structures on PV economics. Solar plus may become an increasingly viable model for optimizing PV customer economics in an evolving rate environment.

Solar Plus: A Holistic Approach to Distributed Solar PV

Energy Technology Data Exchange (ETDEWEB)

OShaughnessy, Eric J. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Ardani, Kristen B. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Cutler, Dylan S. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Margolis, Robert M. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-06-08

Solar 'plus' refers to an emerging approach to distributed solar photovoltaic (PV) deployment that uses energy storage and controllable devices to optimize customer economics. The solar plus approach increases customer system value through technologies such as electric batteries, smart domestic water heaters, smart air-conditioner (AC) units, and electric vehicles We use an NREL optimization model to explore the customer-side economics of solar plus under various utility rate structures and net metering rates. We explore optimal solar plus applications in five case studies with different net metering rates and rate structures. The model deploys different configurations of PV, batteries, smart domestic water heaters, and smart AC units in response to different rate structures and customer load profiles. The results indicate that solar plus improves the customer economics of PV and may mitigate some of the negative impacts of evolving rate structures on PV economics. Solar plus may become an increasingly viable model for optimizing PV customer economics in an evolving rate environment.

Frontier of solar observation. Solar activity observed by 'HINODE' mission

International Nuclear Information System (INIS)

Watanabe, Tetsuya

2008-01-01

After launched in September 2006, solar observation satellite 'HINODE' has been a solar observatory on orbit with the scientific instruments well operated and its continuous observation was conducted steadily on almost all solar atmospheres from photosphere to corona. 'HINODE' was equipped with the solar optical telescope, extreme-ultraviolet imaging spectrometer and x-ray telescope and aimed at clarifying the mystery of solar physics related with coronal heating and magnetic reconnection. Present state of 'HINODE' was described from observations made in initial observation results, which have made several discoveries, such as Alfven waves in the corona, unexpected dynamics in the chromosphere and photosphere, continuous outflowing plasma as a possible source of solar wind, and fine structures of magnetic field in sunspots and solar surface. (T. Tanaka)

Trial products of solar cars; Solar car no shisaku

Energy Technology Data Exchange (ETDEWEB)

Shimizu, A; Hatakeyama, S; Sugiura, S; Shinoda, S; Daigo, Y; Fujihara, Y; Yano, K; Kasuga, M [Yamanashi University, Yamanashi (Japan). Faculty of Engineering

1997-11-25

A solar car was trially manufactured installing solar panels on a motor-wheelchair for the old (senior car). It is a car for one person with maximum speed of 6km/h, motor of 360w, two of storage battery of 12Vtimes29AH, and two of solar cell of 20Vtimes3A. The output of solar cell is about 100W, which may not be enough to drive a 360W motor. However, if action time per day is about 2 hours, the required power 700WH, and the sunshine duration 7 hours per day, solar cells of 100W can generate 700WH. This is stored in battery, and when it is short, it is supplemented by nighttime power. Product prices are 200,000-250,000 yen. A solar go-cart was trially manufactured remodeling the gasoline-run go-cart. It is a solar go-cart for one person with maximum speed of 30km/h, a motor of 600W, four of storage battery of 12Vtimes29AH, and four of solar cell of 20Vtimes3A. The output of solar battery at 200W is a third of the motor power, with battery charged three times the travel time. More than 1000 persons trially rode the go-cart. 2 figs.

Solar Design Workbook

Energy Technology Data Exchange (ETDEWEB)

Franta, G.; Baylin, F.; Crowther, R.; Dubin, F.; Grace, A., Griffith, J.W.; Holtz, M.; Kutscher, C.; Nordham, D.; Selkowitz, S.; Villecco, M.

1981-06-01

This Solar Design Workbook presents solar building design applications for commercial buildir^s. The book is divided into four sections. The first section describes the variety of solar applications in buildings including conservation aspects, solar fundamentals, passive systems, active systems, daylighting, and other solar options. Solar system design evaluation techniques including considerations for building energy requirements, passive systems, active systems, and economics are presented in Section II. The third section attempts to assist the designer in the building design process for energy conservation and solar applications including options and considerations for pre-design, design, and post-design phases. The information required for the solar design proee^ has not been fully developed at this time. Therefore, Section III is incomplete, but an overview of the considerations with some of the design proces elements is presented. Section IV illustrates ease studies that utilize solar applications in the building design.

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

Science.gov (United States)

Longe, Karen M.; McClelland, Michael J.

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

Solar energy in building construction practice. Solar architecture and solar engineering - fundamentals and uses. Sonnenenergie in der Baupraxis. Solar-Architektur und Solar-Technik - Grundlagen und Anwendungen

Energy Technology Data Exchange (ETDEWEB)

Weik, H.; Hahn, G.; Marschall, F.; Meister, H.; Peters, W.; Ranft, F.

1991-01-01

This anthology presents a number of overall suggestions for modern, trend-setting building construction. Details are given about active in addition to passive solar energy utilization, i.e. combinations of solar architecture and solar engineering. In an intelligible way accessible to non-physicist readers, part one discusses the related physicotechnical and town-planning fundamentals. Parts two and three are dedicated to building construction practice. They discuss the various problems of solar energy utilization from the point of view of architects, and refer to economic aspects and thermal insulation. Numerous pictures, diagrams and tables complete the book. (BWI) With 59 figs.

Proceedings of the Canadian Solar Industries Association Solar Forum 2005 : sunny days ahead : a forum on solar energy for government officials

International Nuclear Information System (INIS)

2006-01-01

Solar energy is the fastest growing energy source in the world. Government involvement is critical in the deployment of solar energy. This forum focused on the application of solar energy in government facilities. The forum was divided into 3 sessions: (1) solar technologies and markets; (2) government initiatives that support solar energy; and (3) the use of solar energy on government facilities in Canada. The current state of solar technologies and products in Canada was reviewed. Solar thermal markets were discussed with reference to passive solar energy and photovoltaic applications. On-site solar generation for federal facilities was discussed, and various federal initiatives were reviewed. Issues concerning Ontario's standard offer contract program were discussed. Government users and buyers of solar products spoke of their experiences in using solar energy and the challenges that were faced. The role that solar energy can play in reducing government costs was discussed, as well as the impact of solar energy on the environment. Opportunities and barriers to the use of solar energy in Canada were explored. The conference featured 14 presentations, of which 2 have been catalogued separately for inclusion in this database. refs., tabs., figs

Solar energy collector

Science.gov (United States)

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.

Solar magnetohydrodynamics

International Nuclear Information System (INIS)

Priest, E.R.

1982-01-01

Solar MHD is an important tool for understanding many solar phenomena. It also plays a crucial role in explaining the behaviour of more general cosmical magnetic fields and plasmas, since the Sun provides a natural laboratory in which such behaviour may be studied. While terrestrial experiments are invaluable in demonstrating general plasma properties, conclusions from them cannot be applied uncritically to solar plasmas and have in the past given rise to misconceptions about solar magnetic field behaviour. Important differences between a laboratory plasma on Earth and the Sun include the nature of boundary conditions, the energy balance, the effect of gravity and the size of the magnetic Reynolds number (generally of order unity on the Earth and very much larger on the Sun). The overall structure of the book is as follows. It begins with two introductory chapters on solar observations and the MHD equations. Then the fundamentals of MHD are developed in chapters on magnetostatics, waves, shocks, and instabilities. Finally, the theory is applied to the solar phenomena of atmospheric heating, sunspots, dynamos, flares, prominences, and the solar wind. (Auth.)

SOLAR AIRCRAFT DESIGN

OpenAIRE

RAHMATI, Sadegh; GHASED, Amir

2015-01-01

Abstract. Generally domain Aircraft uses conventional fuel. These fuel having limited life, high cost and pollutant. Also nowadays price of petrol and other fuels are going to be higher, because of scarcity of those fuels. So there is great demand of use of non-exhaustible unlimited source of energy like solar energy. Solar aircraft is one of the ways to utilize solar energy. Solar aircraft uses solar panel to collect the solar radiation for immediate use but it also store the remaining part ...

Solar engine system

International Nuclear Information System (INIS)

Tan, K.K.; Bahrom Sanugi; Chen, L.C.; Chong, K.K.; Jasmy Yunus; Kannan, K.S.; Lim, B.H.; Noriah Bidin; Omar Aliman; Sahar Salehan; Sheikh Ab Rezan Sheikh A H; Tam, C.M.; Chen, Y.T.

2001-01-01

This paper reports the revolutionary solar engine system in Universiti Teknologi Malaysia (UTM). The solar engine is a single cylinder stirling engine driven by solar thermal energy. A first prototype solar engine has been built and demonstrated. A new-concept non-imaging focusing heliostat and a recently invented optical receiver are used in the demonstration. Second generation of prototype solar engine is described briefly. In this paper, the solar engine system development is reported. Measurement for the first prototype engine speed, temperature and specifications are presented. The benefits and potential applications for the future solar engine system, especially for the electricity generating aspect are discussed. (Author)

Solar engineering 1994

International Nuclear Information System (INIS)

Klett, D.E.; Hogan, R.E.; Tanaka, Tadayoshi

1994-01-01

This volume of 83 papers constitutes the Proceedings of the 1994 International Solar Energy Conference held March 27--30, 1994 in San Francisco, California. The Conference was jointly sponsored by the Solar Energy Division of the American Society of Mechanical Engineers, The Japan Society of Mechanical Engineers and the Japan Solar Energy Society. This is the fourth cooperation between ASME, JSME and JSES in cosponsoring the International Solar Energy Conference. The papers cover a wide range of solar technologies from low temperature solar ponds and desalinization to high temperature concentrators for space applications and central receivers for terrestrial power generation. Other topics covered include solar detoxification of hazardous waste, dish Stirling systems, solar cooling, photovoltaics, building energy analysis and conservation, simulation, and testing and measurement techniques. All papers were indexed separately for the data base

Solar array technology evaluation program for SEPS (Solar Electrical Propulsion Stage)

Science.gov (United States)

1974-01-01

An evaluation of the technology and the development of a preliminary design for a 25 kilowatt solar array system for solar electric propulsion are discussed. The solar array has a power to weight ratio of 65 watts per kilogram. The solar array system is composed of two wings. Each wing consists of a solar array blanket, a blanket launch storage container, an extension/retraction mast assembly, a blanket tensioning system, an array electrical harness, and hardware for supporting the system for launch and in the operating position. The technology evaluation was performed to assess the applicable solar array state-of-the-art and to define supporting research necessary to achieve technology readiness for meeting the solar electric propulsion system solar array design requirements.

Solar wind structure out of the ecliptic plane over solar cycles

Science.gov (United States)

Sokol, J. M.; Bzowski, M.; Tokumaru, M.

2017-12-01

Sun constantly emits a stream of plasma known as solar wind. Ground-based observations of the solar wind speed through the interplanetary scintillations (IPS) of radio flux from distant point sources and in-situ measurements by Ulysses mission revealed that the solar wind flow has different characteristics depending on the latitude. This latitudinal structure evolves with the cycle of solar activity. The knowledge on the evolution of solar wind structure is important for understanding the interaction between the interstellar medium surrounding the Sun and the solar wind, which is responsible for creation of the heliosphere. The solar wind structure must be taken into account in interpretation of most of the observations of heliospheric energetic neutral atoms, interstellar neutral atoms, pickup ions, and heliospheric backscatter glow. The information on the solar wind structure is not any longer available from direct measurements after the termination of Ulysses mission and the only source of the solar wind out of the ecliptic plane is the IPS observations. However, the solar wind structure obtained from this method contains inevitable gaps in the time- and heliolatitude coverage. Sokół et al 2015 used the solar wind speed data out of the ecliptic plane retrieved from the IPS observations performed by Institute for Space-Earth Environmental Research (Nagoya University, Japan) and developed a methodology to construct a model of evolution of solar wind speed and density from 1985 to 2013 that fills the data gaps. In this paper we will present a refined model of the solar wind speed and density structure as a function of heliographic latitude updated by the most recent data from IPS observations. And we will discuss methods of extrapolation of the solar wind structure out of the ecliptic plane for the past solar cycles, when the data were not available, as well as forecasting for few years upward.

Solar Heating Systems with Evacuated Tubular Solar Collector

DEFF Research Database (Denmark)

Qin, Lin; Furbo, Simon

1998-01-01

Recently different designed evacuated tubular solar collectors were introduced on the market by different Chinese companies. In the present study, investigations on the performance of four different Chinese evacuated tubular collectors and of solar heating systems using these collectors were...... carried out, employing both laboratory test and theoretical calculations. The collectors were tested in a small solar domestic hot water (SDHW) system in a laboratory test facility under realistic conditions. The yearly thermal performance of solar heating systems with these evacuated tubular collectors......, as well as with normal flat-plate collectors was calculated under Danish weather conditions. It is found that, for small SDHW systems with a combi tank design, an increase of 25% -55% net utilized solar energy can be achieved by using these evacuated tubular collectors instead of normal flat...

Solar air-conditioning. Proceedings

Energy Technology Data Exchange (ETDEWEB)

NONE

2009-07-01

Within the 3rd International Conference on solar air-conditioning in Palermo (Italy) at 30th September to 2nd October, 2009 the following lectures were held: (1) Removal of non-technological barriers to solar cooling technology across Southern European islands (Stefano Rugginenti); (2) The added economic and environmental value of solar thermal systems in microgrids with combined heat and power (Chris Marney); (3) Australian solar cooling interest group (Paul Kohlenbach); (4) Designing of a technology roadmap for solar assisted air conditioning in Austria (Hilbert Focke); (5) Solar cooling in the new context of renewable policies at European level (Raffaele Piria); (6) Prototype of a solar driven steam jet ejector chiller (Clemens Pollerberg); (7) New integrated solar air conditioning system (Joan Carlos Bruno); (8) Primary energy optimised operation of solar driven desiccant evaporative cooling systems through innovative control strategies; (9) Green chiller association (Uli Jakob); (10) Climate Well {sup registered} (Olof Hallstrom); (11) Low capacity absorption chillers for solar cooling applications (Gregor Weidner); (12) Solar cooling in residential, small scale commercial and industrial applications with adsorption technology (Walter Mittelbach); (13) French solar heating and cooling development programme based on energy performance (Daniel Mugnier); (14) Mirrox fresnel process heat collectors for industrial applications and solar cooling (Christian Zahler); (15) Modelling and analyzing solar cooling systems in polysun (Seyen Hossein Rezaei); (16) Solar cooling application in Valle Susa Italy (Sufia Jung); (17) Virtual case study on small solar cooling systems within the SolarCombi+Project (Bjoern Nienborg); (18) Design of solar cooling plants under uncertainty (Fernando Dominguez-Munoz); (19) Fast pre-design of systems using solar thermally driven chillers (Hans-Martin Henning); (20) Design of a high fraction solar heating and cooling plant in southern

Solar Energy Evolution and Diffusion Studies Webinars | Solar Research |

Science.gov (United States)

NREL Studies Webinars Solar Energy Evolution and Diffusion Studies Webinars These webinars . Department of Energy's Solar Energy Evolution and Diffusion Studies (SEEDS) program. SEEDS 2017-2019 Study Residential Solar July 20, 2017 Presenters: Kiran Lakkaraju, Sandia National Laboratories Yevgeniy Vorobeychik

Solar '80s: A Teacher's Handbook for Solar Energy Education.

Science.gov (United States)

LaHart, David E.

This guide is intended to assist the teacher in exploring energy issues and the technology of solar energy conversion and associated technologies. Sections of the guide include: (1) Rationale; (2) Technology Overview; (3) Sun Day Suggestions for School; (4) Backyard Solar Water Heater; (5) Solar Tea; (6) Biogas; (7) Solar Cells; (8) Economics; (9)…

Solar heating systems for houses. A design handbook for solar combisystems

International Nuclear Information System (INIS)

Weiss, W.

2003-11-01

A handbook giving guidance on systems for providing combined solar space heating and solar water heating for houses has been produced by an international team. The guidance focuses on selection of the optimum combi-system for groups of single-family houses and multi-family houses. Standard classification and evaluation procedures are described. The book should be a valuable tool for building engineers, architects, solar manufacturers and installers of solar solar energy systems, and anyone interested in optimizing combined water and space heating solar systems

CERN... Solar Style

CERN Multimedia

2001-01-01

Inventor William van Sprolant presenting the Solar Club's latest invention, the solar fountain. The CERN Solar Club is giving new meaning to the phrase 'fun in the sun' with their most recently developed contraption, the Solar Fountain. The Fountain was presented to the public just outside of Restaurant 1 on Wednesday October, 17th and uses solar energy to run a water pump at its base to propel a golden plastic ball up into the air. As lovely as the fountain is, the funny thing about it is that the height of the water jet and the ball are an artistic method of measuring the amount of solar power being captured by the photovoltaique panel (no batteries included). The day it was presented started out cloudy, but as the afternoon wore on, the weather brightened and the fountain jumped to life. William van Sprolant, the Solar Fountain's inventor, had great fun with the fountain in front of a group of visiting children swiveling the solar panel in multiple directions. 'Everyone who installs solar panels worrie...

Solar workshops financial incentives

Energy Technology Data Exchange (ETDEWEB)

None

1979-01-01

Ten one-day workshops were held across the United States. Information in this workbook is compiled in conjunction with those workshops. The following discussions are included: solar as a fuel (history); why alternative fuels are being sought today; the need for conservation; advantages of solar energy; the potential of solar energy; why solar energy is not more widely used; a definition of solar; how solar can help meet energy demands; Federal policies and programs; what solar technologies exist today that can be effectively utilized (thermal applications, fuels from biomass, solar electric). Additional information is presented in three attachments: Energy-Conserving Methods; Domestic Policy Review of Solar Energy; and DOE Secretary's Annual Report to Congress-Solar Section. (MCW)

Development of a Greek solar map based on solar model estimations

Science.gov (United States)

Kambezidis, H. D.; Psiloglou, B. E.; Kavadias, K. A.; Paliatsos, A. G.; Bartzokas, A.

2016-05-01

The realization of Renewable Energy Sources (RES) for power generation as the only environmentally friendly solution, moved solar systems to the forefront of the energy market in the last decade. The capacity of the solar power doubles almost every two years in many European countries, including Greece. This rise has brought the need for reliable predictions of meteorological data that can easily be utilized for proper RES-site allocation. The absence of solar measurements has, therefore, raised the demand for deploying a suitable model in order to create a solar map. The generation of a solar map for Greece, could provide solid foundations on the prediction of the energy production of a solar power plant that is installed in the area, by providing an estimation of the solar energy acquired at each longitude and latitude of the map. In the present work, the well-known Meteorological Radiation Model (MRM), a broadband solar radiation model, is engaged. This model utilizes common meteorological data, such as air temperature, relative humidity, barometric pressure and sunshine duration, in order to calculate solar radiation through MRM for areas where such data are not available. Hourly values of the above meteorological parameters are acquired from 39 meteorological stations, evenly dispersed around Greece; hourly values of solar radiation are calculated from MRM. Then, by using an integrated spatial interpolation method, a Greek solar energy map is generated, providing annual solar energy values all over Greece.

The Effects of Solar Irradience and Ambient Temperature on Solar ...

African Journals Online (AJOL)

Solar energy is abundant. It is however low grade energy and cannot be easily used in the form it occurs for work. Converting solar energy directly to electricity, using solar photovoltaic (PV) modules is however a low efficiency process. Optimizing this conversion, especially in the face of the high cost of solar panels, is thus ...

Concentrating Solar Power Projects - ISCC Duba 1 | Concentrating Solar

Science.gov (United States)

Solar Break Ground: 2016 Start Production: 2017 Participants Developer(s): Saudi Electricity Co. Owner(s ) (%): Saudi Electricity Co. EPC Contractor: Initec Energia Generation Offtaker(s): Saudi Electricity Co. Plant Configuration Solar Field SCA Manufacturer (Model): Flabeg (Ultimate Trough) HCE Manufacturer: Archimede Solar

Photovoltaic solar cell

Science.gov (United States)

Nielson, Gregory N.; Gupta, Vipin P.; Okandan, Murat; Watts, Michael R.

2015-09-08

A photovoltaic solar concentrator is disclosed with one or more transverse-junction solar cells (also termed point contact solar cells) and a lens located above each solar cell to concentrate sunlight onto the solar cell to generate electricity. Piezoelectric actuators tilt or translate each lens to track the sun using a feedback-control circuit which senses the electricity generated by one or more of the solar cells. The piezoelectric actuators can be coupled through a displacement-multiplier linkage to provide an increased range of movement of each lens. Each lens in the solar concentrator can be supported on a frame (also termed a tilt plate) having three legs, with the movement of the legs being controlled by the piezoelectric actuators.

Solar Power Sources

DEFF Research Database (Denmark)

Kim, Katherine A.; Mentesidi, Konstantina; Yang, Yongheng

2017-01-01

a significant change. Beyond this energy transition, the still declining cost of the solar technology has become an important driving force for more solar-powered systems. However, high penetration of solar-powered systems also brings technical challenges to the entire energy systems. In order to fully address......Solar power is highly abundant, relatively reliable, and not limited to a geographic region, making it one of the most important renewable energy sources. Catering for a clean and green energy system, solar energy will be an active player in the future mixed power grid that is also undergoing...... those issues, the technological properties of solar power should be investigated. Thus, the basics of solar power technology will be introduced and discussed in this chapter....

Photovoltaic solar concentrator

Science.gov (United States)

Nielson, Gregory N.; Gupta, Vipin P.; Okandan, Murat; Watts, Michael R.

2016-03-15

A photovoltaic solar concentrator is disclosed with one or more transverse-junction solar cells (also termed point contact solar cells) and a lens located above each solar cell to concentrate sunlight onto the solar cell to generate electricity. Piezoelectric actuators tilt or translate each lens to track the sun using a feedback-control circuit which senses the electricity generated by one or more of the solar cells. The piezoelectric actuators can be coupled through a displacement-multiplier linkage to provide an increased range of movement of each lens. Each lens in the solar concentrator can be supported on a frame (also termed a tilt plate) having three legs, with the movement of the legs being controlled by the piezoelectric actuators.

Smart solar tanks for small solar domestic hot water systems

DEFF Research Database (Denmark)

Furbo, Simon; Andersen, Elsa; Knudsen, Søren

2005-01-01

Investigation of small SDHW systems based on smart solar tanks are presented. The domestic water in a smart solar tank can be heated both by solar collectors and by means of an auxiliary energy supply system. The auxiliary energy supply system – in this study electric heating elements – heats up...... systems, based on differently designed smart solar tanks and a traditional SDHW system were investigated by means of laboratory experiments and theoretical calculations. The investigations showed that the yearly thermal performance of SDHW systems with smart solar tanks is 5-35% higher than the thermal...... performance of traditional SDHW systems. Estimates indicate that the performance/cost ratio can be improved by up to 25% by using a smart solar tank instead of a traditional tank when the backup energy system is electric heating elements. Further, smart solar tanks are suitable for unknown, variable, large...

The solar kettle-thermos flask (SK-TF) and solar vacuum tube oven

Energy Technology Data Exchange (ETDEWEB)

Yak, Alex Kee Koo [AkayConsult Enterprise, Johor Bahru (Malaysia)

2008-07-01

The Solar Kettle-Thermos Flask (SK-TF) and Solar Vacuum Tube Oven (SaVeTao): A Cost Effective, Sustainable and Renewable Water Pasteurization and Food Processing System For The Developing World. Based on the perfect solar thermal energy harvesting paradigm of maximum solar radiation absorption and minimum loss of stored converted solar thermal energy, Solar Vacuum Glass Tubes (SVGT) indefinitely delivers solar pasteurized safe drinking water, powered solely by free solar energy. The SVGT is the heart of the SK-TF. Being vacuum insulated, the SK-TF doubles up as a vacuum flask, delivering stored solar heated water in the morning before the Sun is up. With a high stagnation temperature of more than 200 C, the SK-TF can also be used for other heating purposes e.g. an oven or autoclave. Powered solely by free solar energy, the SK-TF and SaVeTaO could very well be the answer in providing safe solar pasteurized drinking water and cooking to the global poor and needy in a sustainable and renewable way. (orig.)

Solar Simulator

Science.gov (United States)

1981-01-01

Oriel Corporation's simulators have a high pressure xenon lamp whose reflected light is processed by an optical system to produce a uniform solar beam. Because of many different types of applications, the simulators must be adjustable to replicate many different areas of the solar radiation spectrum. Simulators are laboratory tools for such purposes as testing and calibrating solar cells, or other solar energy systems, testing dyes, paints and pigments, pharmaceuticals and cosmetic preparations, plant and animal studies, food and agriculture studies and oceanographic research.

Solar collector array

Science.gov (United States)

Hall, John Champlin; Martins, Guy Lawrence

2015-09-06

A method and apparatus for efficient manufacture, assembly and production of solar energy. In one aspect, the apparatus may include a number of modular solar receiver assemblies that may be separately manufactured, assembled and individually inserted into a solar collector array housing shaped to receive a plurality of solar receivers. The housing may include optical elements for focusing light onto the individual receivers, and a circuit for electrically connecting the solar receivers.

Impacts of the Solar Investment Tax Credit On State-Level Solar Outcomes

OpenAIRE

Kolachalam, Sriman

2017-01-01

In this paper, I investigate the effects of the U.S. federally implemented Solar Investment Tax Credit (ITC) on states’ solar energy installation and utilization. In particular, I compare relative trends in solar installation and utilization between states with initially higher levels of solar and states with initially lower levels of solar, before and after the implementation of the Solar ITC. My findings demonstrate that states with initially higher level...

Lower extremity robotic exoskeleton training: Case studies for complete spinal cord injury walking.

Science.gov (United States)

Lemaire, Edward D; Smith, Andrew J; Herbert-Copley, Andrew; Sreenivasan, Vidya

2017-01-01

Recent advances in exoskeleton technology has made lower extremity powered exoskeletons (LEPE) a viable treatment tool to restore upright walking mobility to persons with spinal cord injury (SCI). Evaluate ARKE exoskeleton training within a rehabilitation centre environment. Case studies are presented for two male participants, age 41 and 30, motor complete SCI at T6 (N01) and T12 (N02), respectively, as they progress from new LEPE users to independent walking. The ARKE 2.0 LEPE (Bionik Laboratories Inc., Toronto, Canada) was used for all training (hip and knee powered, forearm crutches, control tablet). Data were collected on session times, activity metrics from ARKE system logs, and qualitative questionnaire feedback. N01 required 18, 30-minute training sessions to achieve independent walking. N01 walked independently within the 12 session target. Foot strikes were frequently before the end of the programmed swing phase, which were handled by the ARKE control system. Subjective ratings of LEPE learning, comfort, pain, fatigue, and overall experience were high for sitting-standing and moderate to high for walking. This reflected the complexity of learning to safely walk. Qualitative feedback supported the continuation of LEPE use in rehabilitation settings based on end-user desire for upright mobility.

Solar neutrinos and solar accretion of interstellar matter

International Nuclear Information System (INIS)

Newman, M.J.; Talbot, R.J. Jr.

1976-01-01

It is argued that if the Hoyle-Lyttleton mass accretion rate applies (Proc. Camb. Phil. Soc., Math. Phys. Sci. 35: 405 (1939)) the accretion of interstellar matter by the Sun is sufficient to enhance the surface heavy element abundances. This will also apply to other solar-type stars. The enhancement may be sufficient to allow the construction of consistent solar models with an interior heavy element abundance significantly lower than the observed surface abundance. This state of affairs lowers the predicted solar neutrino flux. It has been suggested that a similar enhancement of surface abundances might occur due to accretion of 'planetesimals' left over after formation of the solar system, and both processes may occur, thereby increasing the effect. The simple accretion model of Hoyle and Lyttleton is discussed mathematically. A crucial question to be answered by future research, however, is whether or not accretion on to the solar surface actually occurs. One of the most obvious obstacles is the outward flowing solar wind, and this is discussed. It appears that the outward flow can be reversed to an inward flow for certain interstellar cloud densities. (U.K.)

Solar action: solar hot water in The Netherlands

International Nuclear Information System (INIS)

Van de Water, Adrie

2001-01-01

This paper focuses on the use of solar hot water systems in the Netherlands, and reports on the Dutch Solar Domestic Hot Water System agreement signed in 1999 and set up to enhance the development of the market for solar domestic hot water (SDHW) systems and their application as a sustainable energy source. The Dutch Thermal Solar Energy Programme's objectives and goals, the subsidy schemes for thermal solar energy administered by Senter - an agency of the Ministry of Economic Affairs (MEA), and the project-based and individual approaches to boosting the sales of SDHW systems are examined. Large system sales, the targeting of consumers via a national campaign, and national publicity using the slogan 'Sustainable energy. Goes without saying' commissioned by the MEA are discussed along with the support shown by the Dutch power distribution companies for SDHW systems, marketing aspects, and the outlook for sales of SDHW systems

Introduction to solar cell production

International Nuclear Information System (INIS)

Kim, Gyeong Hae; Lee, Jun Sin

2009-08-01

This book introduces solar cell production. It is made up eight chapters, which are summary of solar cell with structure and prospect of the business, special variable of solar cell on light of the sun and factor causing variable of solar cell, production of solar cell with surface texturing, diffusion, metal printing dry and firing and edge isolation, process of solar cell on silicone wafer for solar cell, forming of electrodes, introduction of thin film solar cell on operating of solar cell, process of production and high efficiency of thin film solar cell, sorting of solar cell and production with background of silicone solar cell and thin film solar cell, structure and production of thin film solar cell and compound solar cell, introduction of solar cell module and the Industrial condition and prospect of solar cell.

Solar constraints

International Nuclear Information System (INIS)

Provost, J.

1984-01-01

Accurate tests of the theory of stellar structure and evolution are available from the Sun's observations. The solar constraints are reviewed, with a special attention to the recent progress in observing global solar oscillations. Each constraint is sensitive to a given region of the Sun. The present solar models (standard, low Z, mixed) are discussed with respect to neutrino flux, low and high degree five-minute oscillations and low degree internal gravity modes. It appears that actually there do not exist solar models able to fully account for all the observed quantities. (Auth.)

SOLAR WIND HEAVY IONS OVER SOLAR CYCLE 23: ACE/SWICS MEASUREMENTS

International Nuclear Information System (INIS)

Lepri, S. T.; Landi, E.; Zurbuchen, T. H.

2013-01-01

Solar wind plasma and compositional properties reflect the physical properties of the corona and its evolution over time. Studies comparing the previous solar minimum with the most recent, unusual solar minimum indicate that significant environmental changes are occurring globally on the Sun. For example, the magnetic field decreased 30% between the last two solar minima, and the ionic charge states of O have been reported to change toward lower values in the fast wind. In this work, we systematically and comprehensively analyze the compositional changes of the solar wind during cycle 23 from 2000 to 2010 while the Sun moved from solar maximum to solar minimum. We find a systematic change of C, O, Si, and Fe ionic charge states toward lower ionization distributions. We also discuss long-term changes in elemental abundances and show that there is a ∼50% decrease of heavy ion abundances (He, C, O, Si, and Fe) relative to H as the Sun went from solar maximum to solar minimum. During this time, the relative abundances in the slow wind remain organized by their first ionization potential. We discuss these results and their implications for models of the evolution of the solar atmosphere, and for the identification of the fast and slow wind themselves.

Coordinated weather balloon solar radiation measurements during a solar eclipse.

Science.gov (United States)

Harrison, R G; Marlton, G J; Williams, P D; Nicoll, K A

2016-09-28

Solar eclipses provide a rapidly changing solar radiation environment. These changes can be studied using simple photodiode sensors, if the radiation reaching the sensors is unaffected by cloud. Transporting the sensors aloft using standard meteorological instrument packages modified to carry extra sensors, provides one promising but hitherto unexploited possibility for making solar eclipse radiation measurements. For the 20 March 2015 solar eclipse, a coordinated campaign of balloon-carried solar radiation measurements was undertaken from Reading (51.44°N, 0.94°W), Lerwick (60.15°N, 1.13°W) and Reykjavik (64.13°N, 21.90°W), straddling the path of the eclipse. The balloons reached sufficient altitude at the eclipse time for eclipse-induced variations in solar radiation and solar limb darkening to be measured above cloud. Because the sensor platforms were free to swing, techniques have been evaluated to correct the measurements for their changing orientation. In the swing-averaged technique, the mean value across a set of swings was used to approximate the radiation falling on a horizontal surface; in the swing-maximum technique, the direct beam was estimated by assuming that the maximum solar radiation during a swing occurs when the photodiode sensing surface becomes normal to the direction of the solar beam. Both approaches, essentially independent, give values that agree with theoretical expectations for the eclipse-induced radiation changes.This article is part of the themed issue 'Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse'. © 2016 The Authors.

Development of nonmetallic solar collector and solar-powered pump

Science.gov (United States)

Parker, J. C.

1979-01-01

Design and building of two unique components for solar heating (1. flatplate solar collector using no metal components, and 2. solar powered pump for heating and cooling systems are outlined in report. Report also discusses hardware, deliverable end items, problems encountered during fabrication and testing, and performance certification.

Solar thermal

International Nuclear Information System (INIS)

Jones, J.

2006-01-01

While wind power is widely acknowledged as the most developed of the 'new' renewables, the number two technology, in terms of installed capacity functioning worldwide, is solar heating, or solar thermal. The author has investigated recent industry reports on how these markets are developing. The authors of an International Energy Agency (IEA) survey studied 41 countries in depth at the end of 2004, revealing that 141 million m 3 - corresponding to an installed capacity of 98.4 GWth - were installed in the sample countries (these nations represent 3.74 billion people, about 57% of the world's population). The installed capacity within the areas studied represents approximately 85%-90% of the solar thermal market worldwide. The use of solar heating varies greatly between countries - even close neighbours - and between economic regions. Its uptake often has more to do with policy than solar resource. There is also different uptake of technology. In China, Europe and Japan, plants with flat-plate and evacuated tube collectors are used, mainly to heat water and for space heating. Unglazed plastic collectors, used mainly for swimming pool heating, meanwhile, dominate the North American markets. Though the majority of solar heating installations today are installed on domestic rooftops, the larger-scale installations should not be overlooked. One important part of the market is the hotel sector - in particular hotels in locations that serve the seasonal summer holiday market, where solar is extremely effective. Likewise hospitals and residential homes, multi-family apartment blocks and sports centres are all good examples of places where solar thermal can deliver results. There are also a growing number of industrial applications, where solar thermal can meet the hot water needs (and possibly more) of a range of industries, such as food processing and agriculture. The ability of solar to provide a heat source for cooling is expected to become increasingly important as

Solar thermal

Energy Technology Data Exchange (ETDEWEB)

Jones, J.

2006-07-15

While wind power is widely acknowledged as the most developed of the 'new' renewables, the number two technology, in terms of installed capacity functioning worldwide, is solar heating, or solar thermal. The author has investigated recent industry reports on how these markets are developing. The authors of an International Energy Agency (IEA) survey studied 41 countries in depth at the end of 2004, revealing that 141 million m{sup 3} - corresponding to an installed capacity of 98.4 GWth - were installed in the sample countries (these nations represent 3.74 billion people, about 57% of the world's population). The installed capacity within the areas studied represents approximately 85%-90% of the solar thermal market worldwide. The use of solar heating varies greatly between countries - even close neighbours - and between economic regions. Its uptake often has more to do with policy than solar resource. There is also different uptake of technology. In China, Europe and Japan, plants with flat-plate and evacuated tube collectors are used, mainly to heat water and for space heating. Unglazed plastic collectors, used mainly for swimming pool heating, meanwhile, dominate the North American markets. Though the majority of solar heating installations today are installed on domestic rooftops, the larger-scale installations should not be overlooked. One important part of the market is the hotel sector - in particular hotels in locations that serve the seasonal summer holiday market, where solar is extremely effective. Likewise hospitals and residential homes, multi-family apartment blocks and sports centres are all good examples of places where solar thermal can deliver results. There are also a growing number of industrial applications, where solar thermal can meet the hot water needs (and possibly more) of a range of industries, such as food processing and agriculture. The ability of solar to provide a heat source for cooling is expected to become

Availability of solar radiation and standards for solar access

Energy Technology Data Exchange (ETDEWEB)

Casabianca, G.A.; Evans, J.M. [Research Centre Habitat and Energy, Facultad de Arquitectura, Diseno y Urbanismo, Universidad de Buenos Aires, Capital Federal (Argentina)

1997-12-31

In southern Argentina, a region between latitudes 38 deg C and 55 deg C S, the heating demand in the residential sector is high while the availability of solar radiation is limited. A new proposal for solar access standards has been developed, taking into account the climatic conditions of each location, the effective availability of solar radiation and the direct sunlight requirements. This study analyses the climatic conditions for the Patagonia, relating heating demand and solar radiation availability in different sites, and presents the development of new sunlight standards that respond to these regional conditions. As a result of this study, the new Argentine standard TRAM 11.603 includes new conditions to protect solar access and provide design recommendations. (orig.) 4 refs.

Solar Energy Technician/Installer

Science.gov (United States)

Moore, Pam

2007-01-01

Solar power (also known as solar energy) is solar radiation emitted from the sun. Large panels that absorb the sun's energy as the sun beats down on them gather solar power. The energy in the rays can be used for heat (solar thermal energy) or converted to electricity (photovoltaic energy). Each solar energy project, from conception to…

Solar Energy and You.

Science.gov (United States)

Conservation and Renewable Energy Inquiry and Referral Service (DOE), Silver Spring, MD.

This booklet provides an introduction to solar energy by discussing: (1) how a home is heated; (2) how solar energy can help in the heating process; (3) the characteristics of passive solar houses; (4) the characteristics of active solar houses; (5) how solar heat is stored; and (6) other uses of solar energy. Also provided are 10 questions to…

Solar energy an introduction

CERN Document Server

Mackay, Michael E

2015-01-01

Solar Energy presents an introduction to all aspects of solar energy, from photovoltaic devices to active and passive solar thermal energy conversion, giving both a detailed and broad perspective of the field. It is aimed at the beginner involved in solar energy or a related field, or for someone wanting to gain a broader perspective of solar energy technologies. A chapter considering solar radiation, basic principles applied to solar energy, semiconductor physics, and light absorption brings the reader on equal footing with the technology of either solar generated electrical current or useful heat. Details of how a solar cell works and then production of current from a photovoltaic device is discussed. Characterization of a solar cell is examined, allowing one the ability to interpret the current-voltage relation, followed by discussion of parameter extraction from this relation. This information can be used to understand what limits the performance of a given solar cell with the potential to optimize its pe...

Solar energy guide

International Nuclear Information System (INIS)

Lentz, A.; Winter, R.

1993-07-01

Many aspects with regard to the practical use of solar energy are discussed. This guide is aimed at informing local and regional administrators, committee members of housing corporations and public utilities and public relations officers on the possibilities to use solar energy. In chapter one an overview is given of the use of solar energy in the housing sector, the recreational sector, agricultural sector, industry, trade and other sectors. In the chapters two, three and four attention is paid to passive solar energy, active thermal solar energy and photovoltaic energy respectively. In the chapters five and six aspects concerning the implementation of solar energy systems in practice are discussed. First an outline of the parties involved in implementing solar energy is given: the municipality, the energy utility, the province, local authorities, advisors, housing constructors and the occupants of the buildings. Then attention is paid to the consequences of implementing solar energy for the building inspection and regulations, the finances, energy savings and the environment. In chapter seven an overview is given of the subsidy regulations of the European Community, the Dutch national and local governments. Chapter contains addresses of solar thermal systems, photovoltaic systems and other institutes operating in the field of solar energy, as well as the titles of a number of brochures and courses. 51 figs., 7 tabs., 86 refs

Solar storms; Tormentas solares

Energy Technology Data Exchange (ETDEWEB)

Collaboration: Pereira Cuesta, S.; Pereira Pagan, B.

2016-08-01

Solar storms begin with an explosion, or solar flare, on the surface of the sun. The X-rays and extreme ultraviolet radiation from the flare reach the Earths orbit minutes later-travelling at light speed. The ionization of upper layers of our atmosphere could cause radio blackouts and satellite navigation errors (GPS). Soon after, a wave of energetic particles, electrons and protons accelerated by the explosion crosses the orbit of the Earth, and can cause real and significant damage. (Author)

Characteristic studies on solar x-ray flares and solar radio bursts during descending phases of solar cycles 22 and 23

International Nuclear Information System (INIS)

Bhattacharya, J.; De, B.K.; Guha, A.

2014-01-01

In this paper, a comparative study between the solar X-ray flares and solar radio bursts in terms of their duration and energy has been done. This has been done by analyzing the data in a statistical way covering the descending phase of the 22nd and 23rd solar cycles. It has been observed that the most probable value of duration of both solar X-ray flares and solar radio bursts remain same for a particular cycle. There is a slight variation in the most probable value of duration in going from 22nd cycle to 23rd cycle in the case of both kinds of events. This small variation may be due to the variation of polar field. A low correlation has been observed between energy fluxes in solar X-ray flares and in solar radio bursts. This has been attributed to the non symmetric contribution of energy to the solar radio and X-ray band controlled by solar magnetic field

Solar energy modulator

Science.gov (United States)

Hale, R. R. (Inventor); Mcdougal, A. R.

1984-01-01

A module is described with a receiver having a solar energy acceptance opening and supported by a mounting ring along the optic axis of a parabolic mirror in coaxial alignment for receiving solar energy from the mirror, and a solar flux modulator plate for varying the quantity of solar energy flux received by the acceptance opening of the module. The modulator plate is characterized by an annular, plate-like body, the internal diameter of which is equal to or slightly greater than the diameter of the solar energy acceptance opening of the receiver. Slave cylinders are connected to the modulator plate for supporting the plate for axial displacement along the axis of the mirror, therby shading the opening with respect to solar energy flux reflected from the surface of the mirror to the solar energy acceptance opening.

A hybrid solar chemical looping combustion system with a high solar share

International Nuclear Information System (INIS)

Jafarian, Mehdi; Arjomandi, Maziar; Nathan, Graham J.

2014-01-01

Highlights: • A novel hybrid solar chemical looping combustion system is presented. • This hybrid CLC system integrates a CLC plant with a solar thermal energy plant. • The oxygen carrier particles are used for chemical and sensible thermal energy storage. • A solar cavity reactor is proposed for fuel reactor. • The calculations show a total solar share of around 60% can be achieved. - Abstract: A novel hybrid solar chemical looping combustion (Hy-Sol-CLC) is presented, in which the oxygen carrier particles in a CLC system are employed to provide thermal energy storage for concentrated solar thermal energy. This hybrid aims to take advantage of key features of a chemical looping combustion (CLC) system that are desirable for solar energy systems, notably their inherent chemical and sensible energy storage systems, the relatively low temperature of the “fuel” reactor (to which the concentrated solar thermal energy is added in a hybrid) relative to that of the final temperature of the product gas and the potential to operate the fuel reactor at a different pressure to the heated gas stream. By this approach, it is aimed to achieve high efficiency of the solar energy, infrastructure sharing, economic synergy, base load power generation and a high solar fraction of the total energy. In the proposed Hy-Sol-CLC system, a cavity solar receiver has been chosen for fuel reactor while for the storage of the oxygen carrier particles two reservoirs have been added to a conventional CLC. A heat exchanger is also proposed to provide independent control of the temperatures of the storage reservoirs from those of solar fuel and air reactors. The system is simulated using Aspen Plus software for the average diurnal profile of normal irradiance for Port Augusta, South Australia. The operating temperature of the fuel reactor, solar absorption efficiency, solar share, fraction of the solar thermal energy stored within the solar reactor, the fractions of sensible and

Solar and terrestrial physics. [effects of solar activities on earth environment

Science.gov (United States)

1975-01-01

The effects of solar radiation on the near space and biomental earth, the upper atmosphere, and the magnetosphere are discussed. Data obtained from the OSO satellites pertaining to the solar cycle variation of extreme ultraviolet (EUV) radiation are analyzed. The effects of solar cycle variation of the characteristics of the solar wind are examined. The fluid mechanics of shock waves and the specific relationship to the characteristics of solar shock waves are investigated. The solar and corpuscular heating of the upper atmosphere is reported based on the findings of the AEROS and NATE experiments. Seasonal variations of the upper atmosphere composition are plotted based on OGO-6 mass spectrometer data.

The SolarPACES strategy for the solar thermal breakthrough

Energy Technology Data Exchange (ETDEWEB)

Burch, G.D. [U.S. Department of Energy, Washington, DC (United States)

1997-12-31

Our national solar thermal research programs and our combined efforts conducted through IEA/SolarPACES have brought about many breakthroughs in the development of solar thermal technology. We have components and systems that are much more efficient, much more reliable, and can be built much more cost-efficiently than just a few years ago. As our technology development proceeds, we undoubtedly will continue to make significant progress, breakthroughs in fact, in all these areas - progress that will bring us even closer to economic parity with more conventional forms of energy. And while this progress is absolutely necessary, the question is whether it will be enough to allow solar thermal to break into the mainstream of global energy supply. Our new IEA/SolarPACES strategy, crafted and approved over the course of the past year, has recognized the changes we must face and given us license to begin to make those changes. We must begin addressing financial hurdles, work to create a more favorable regulatory and tax environment, support development of international partnerships, and expand the visibility and excitement of solar thermal technology to achieve the final breakthroughs we need to allow solar thermal energy to live up to its vast potential. (orig./AKF)

Solar energy conversion

Energy Technology Data Exchange (ETDEWEB)

Kistler, J.

1981-08-05

The photovoltaic generator is the central part of all solar systems. Flat solar cells embedded in glass are preferred which can also convert diffuse solar radiation. Hybrid modules generate electrical and thermal energy simultaneously. With decreasing generator cost, the cost of energy storage becomes critical. Development activities are mostly directed on the development of stationary lead accumulator batteries and the electronic charging and protective systems. The block diagram of the current converter is presented, and applications of solar systems in domestic heating engineering, transportation technology, communications, and hydrological engineering. Solar villages are recommended which, established in bilateral cooperation with Third World authorities, may demonstrate the advantages of solar energy in heat and electric power generation.

Solar cosmic rays in the system of solar terrestrial relations

Science.gov (United States)

Miroshnichenko, Leonty I.

2008-02-01

In this brief review, we discuss a number of geophysical effects of solar energetic particles (SEPs) or solar cosmic rays (SCR). We concentrate mainly on the observational evidence and proposed mechanisms of some expected effects and/or poor-studied phenomena discovered within the last three decades, in particular, depletion of the ozone layer, perturbations in the global electric current, effects on the winter storm vorticity, change of the atmospheric transparency and production of nitrates. Some "archaeological" data on SCR fluxes in the past and upper limit of total energy induced by SEPs are also discussed. Due attention is paid to the periodicities in the solar particle fluxes. Actually, many solar, heliospheric and terrestrial parameters changing generally in phase with the solar activity are subjected to a temporary depression close to the solar maximum ("Gnevyshev Gap"). A similar gap has been found recently in the yearly numbers of the >10 MeV proton events. All the above-mentioned findings are evidently of great importance in the studies of general proton emissivity of the Sun and long-term trends in the behaviour of solar magnetic fields. In addition, these data can be very helpful for elaborating the methods for prediction of the radiation conditions in space and for estimation of the SEPs' contribution to solar effects on the geosphere, their relative role in the formation of terrestrial weather and climate and in the problem of solar-terrestrial relations (STR) on the whole.

Deciphering solar magnetic activity: on grand minima in solar activity

Energy Technology Data Exchange (ETDEWEB)

McIntosh, Scott W. [High Altitude Observatory, National Center for Atmospheric Research, Boulder, CO (United States); Leamon, Robert J., E-mail: mscott@ucar.edu [Department of Physics, Montana State University, Bozeman, MT (United States)

2015-07-08

The Sun provides the energy necessary to sustain our existence. While the Sun provides for us, it is also capable of taking away. The weather and climatic scales of solar evolution and the Sun-Earth connection are not well- understood. There has been tremendous progress in the century since the discovery of solar magnetism—magnetism that ultimately drives the electromagnetic, particulate, and eruptive forcing of our planetary system. There is contemporary evidence of a decrease in solar magnetism, perhaps even indicators of a significant downward trend, over recent decades. Are we entering a minimum in solar activity that is deeper and longer than a typical solar minimum, a “grand minimum”? How could we tell if we are? What is a grand minimum and how does the Sun recover? These are very pertinent questions for modern civilization. In this paper we present a hypothetical demonstration of entry and exit from grand minimum conditions based on a recent analysis of solar features over the past 20 years and their possible connection to the origins of the 11(&ish) year solar activity cycle.

Deciphering Solar Magnetic Activity: On Grand Minima in Solar Activity

Directory of Open Access Journals (Sweden)

Scott William Mcintosh

2015-07-01

Full Text Available The Sun provides the energy necessary to sustain our existence. While the Sun provides for us, it is also capable of taking away. The weather and climatic scales of solar evolution and the Sun-Earth connection are not well understood. There has been tremendous progress in the century since the discovery of solar magnetism - magnetism that ultimately drives the electromagnetic, particulate and eruptive forcing of our planetary system. There is contemporary evidence of a decrease in solar magnetism, perhaps even indicators of a significant downward trend, over recent decades. Are we entering a minimum in solar activity that is deeper and longer than a typical solar minimum, a grand minimum? How could we tell if we are? What is a grand minimum and how does the Sun recover? These are very pertinent questions for modern civilization. In this paper we present a hypothetical demonstration of entry and exit from grand minimum conditions based on a recent analysis of solar features over the past 20 years and their possible connection to the origins of the 11(-ish year solar activity cycle.

Deciphering Solar Magnetic Activity: On Grand Minima in Solar Activity

Science.gov (United States)

Mcintosh, Scott; Leamon, Robert

2015-07-01

The Sun provides the energy necessary to sustain our existence. While the Sun provides for us, it is also capable of taking away. The weather and climatic scales of solar evolution and the Sun-Earth connection are not well understood. There has been tremendous progress in the century since the discovery of solar magnetism - magnetism that ultimately drives the electromagnetic, particulate and eruptive forcing of our planetary system. There is contemporary evidence of a decrease in solar magnetism, perhaps even indicators of a significant downward trend, over recent decades. Are we entering a minimum in solar activity that is deeper and longer than a typical solar minimum, a "grand minimum"? How could we tell if we are? What is a grand minimum and how does the Sun recover? These are very pertinent questions for modern civilization. In this paper we present a hypothetical demonstration of entry and exit from grand minimum conditions based on a recent analysis of solar features over the past 20 years and their possible connection to the origins of the 11(-ish) year solar activity cycle.

Connectable solar air collectors

Energy Technology Data Exchange (ETDEWEB)

Oestergaard Jensen, S.; Bosanac, M.

2002-02-01

The project has proved that it is possible to manufacture solar air collector panels, which in an easy way can be connected into large collector arrays with integrated ducting without loss of efficiency. The developed connectable solar air collectors are based on the use of matrix absorbers in the form of perforated metal sheets. Three interconnected solar air collectors of the above type - each with an transparent area of approx. 3 m{sup 2} - was tested and compared with parallel tests on two single solar air collectors also with a transparent area of approx. 3 m{sup 2} One of the single solar air collectors has an identical absorber as the connectable solar air collectors while the absorber of the other single solar air collector was a fibre cloth. The efficiency of the three solar air collectors proved to be almost identical in the investigated range of mass flow rates and temperature differences. The solar air collectors further proved to be very efficient - as efficient as the second most efficient solar air collectors tested in the IEA task 19 project Solar Air Systems. Some problems remain although to be solved: the pressure drop across especially the connectable solar air collectors is too high - mainly across the inlets of the solar air collectors. It should, however, be possible to considerably reduce the pressure losses with a more aerodynamic design of the inlet and outlet of the solar air collectors; The connectable solar air collectors are easy connectable but the air tightness of the connections in the present form is not good enough. As leakage leads to lower efficiencies focus should be put on making the connections more air tight without loosing the easiness in connecting the solar air collectors. As a spin off of the project a simple and easy way to determine the efficiency of solar, air collectors for pre-heating of fresh air has been validated. The simple method of determining the efficiency has with success been compared with an advance method

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

Energy Technology Data Exchange (ETDEWEB)

Strahs, G.; Tombari, C.

2006-10-01

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

Coupling of Luminescent Solar Concentrators to Plasmonic Solar Cells

Science.gov (United States)

Wang, Shu-Yi

To make inexpensive solar cells is a continuous goal for solar photovoltaic (PV) energy industry. Thin film solar cells of various materials have been developed and continue to emerge in order to replace bulk silicon solar cells. A thin film solar cell not only uses less material but also requires a less expensive refinery process. In addition, other advantages coming along with small thickness are higher open circuit voltage and higher conversion efficiency. However, thin film solar cells, especially those made of silicon, have significant optical losses. In order to address this problem, this thesis investigates the spectral coupling of thin films PV to luminescent solar concentrators (LSC). LSC are passive devices, consisting of plastic sheets embedded with fluorescent dyes which absorb part of the incoming radiation spectrum and emit at specific wavelength. The emitted light is concentrated by total internal reflection to the edge of the sheet, where the PVs are placed. Since the light emitted from the LSC edge is usually in a narrow spectral range, it is possible to employ diverse strategies to enhance PV absorption at the peak of the emission wavelength. Employing plasmonic nanostructures has been shown to enhance absorption of thin films via forward scattering, diffraction and localized surface plasmon. These two strategies are theoretically investigated here for improving the absorption and elevating the output power of a thin film solar cell. First, the idea of spectral coupling of luminescent solar concentrators to plasmonic solar cells is introduced to assess its potential for increasing the power output. This study is carried out employing P3HT/PC60BM organic solar cells and LSC with Lumogen Red dyes. A simplified spectral coupling analysis is employed to predict the power density, considering the output spectrum of the LSC equivalent to the emission spectrum of the dye and neglecting any angular dependence. Plasmonic tuning is conducted to enhance

Solar coronal non-thermal processes (Solar Maximum Mission). Final report

International Nuclear Information System (INIS)

Hudson, H.S.

1983-02-01

The Solar Maximum Mission was used to study solar coronal phenomena in hard X-radiation, since its instrument complement included the first solar hard X-ray telescope. Phenomena related to those discovered from OSO-5 and OSO-7 observations were emphasized

Characteristics of Solar Wind Density Depletions During Solar Cycles 23 and 24

Directory of Open Access Journals (Sweden)

Keunchan Park

2017-06-01

Full Text Available Solar wind density depletions are phenomena that solar wind density is rapidly decreased and keep the state. They are generally believed to be caused by the interplanetary (IP shocks. However, there are other cases that are hardly associated with IP shocks. We set up a hypothesis for this phenomenon and analyze this study. We have collected the solar wind parameters such as density, speed and interplanetary magnetic field (IMF data related to the solar wind density depletion events during the period from 1996 to 2013 that are obtained with the advanced composition explorer (ACE and the Wind satellite. We also calculate two pressures (magnetic, dynamic and analyze the relation with density depletion. As a result, we found total 53 events and the most these phenomena’s sources caused by IP shock are interplanetary coronal mass ejection (ICME. We also found that solar wind density depletions are scarcely related with IP shock’s parameters. The solar wind density is correlated with solar wind dynamic pressure within density depletion. However, the solar wind density has an little anti-correlation with IMF strength during all events of solar wind density depletion, regardless of the presence of IP shocks. Additionally, In 47 events of IP shocks, we find 6 events that show a feature of blast wave. The quantities of IP shocks are weaker than blast wave from the Sun, they are declined in a short time after increasing rapidly. We thus argue that IMF strength or dynamic pressure are an important factor in understanding the nature of solar wind density depletion. Since IMF strength and solar wind speed varies with solar cycle, we will also investigate the characteristics of solar wind density depletion events in different phases of solar cycle as an additional clue to their physical nature.

Apparent Relations Between Solar Activity and Solar Tides Caused by the Planets

Science.gov (United States)

Hung, Ching-Cheh

2007-01-01

A solar storm is a storm of ions and electrons from the Sun. Large solar storms are usually preceded by solar flares, phenomena that can be characterized quantitatively from Earth. Twenty-five of the thirty-eight largest known solar flares were observed to start when one or more tide-producing planets (Mercury, Venus, Earth, and Jupiter) were either nearly above the event positions (less than 10 deg. longitude) or at the opposing side of the Sun. The probability for this to happen at random is 0.039 percent. This supports the hypothesis that the force or momentum balance (between the solar atmospheric pressure, the gravity field, and magnetic field) on plasma in the looping magnetic field lines in solar corona could be disturbed by tides, resulting in magnetic field reconnection, solar flares, and solar storms. Separately, from the daily position data of Venus, Earth, and Jupiter, an 11-year planet alignment cycle is observed to approximately match the sunspot cycle. This observation supports the hypothesis that the resonance and beat between the solar tide cycle and nontidal solar activity cycle influences the sunspot cycle and its varying magnitudes. The above relations between the unpredictable solar flares and the predictable solar tidal effects could be used and further developed to forecast the dangerous space weather and therefore reduce its destructive power against the humans in space and satellites controlling mobile phones and global positioning satellite (GPS) systems.

Solar energy utilization by solar cells and superblack absorbers

Energy Technology Data Exchange (ETDEWEB)

Bonnet, D; Selders, M

1975-10-31

A review is presented of the physical principles responsible for the characteristics of solar cells, with particular reference to Si homojunction and CdS--Cu/sub 2/S thin film devices. Electric power generation from solar cells still appears uncompetitive economically except in special circumstances, but heating from solar energy using selective absorbers with low reemission is more promising.

Solar electricity potentials and optimal angles for mounting solar ...

African Journals Online (AJOL)

The need for harnessing solar energy using solar panels mounted at optimal inclination angles in the six geopolitical zones of Nigeria is presented. The optimal angle for mounting solar panels as presented by Photovoltaic Geographic Information System (PVGIS) ranges from 11º to 14º in the Southern zone and 13º to 16º ...

Detecting photovoltaic solar panels using hyperspectral imagery and estimating solar power production

Science.gov (United States)

Czirjak, Daniel

2017-04-01

Remote sensing platforms have consistently demonstrated the ability to detect, and in some cases identify, specific targets of interest, and photovoltaic solar panels are shown to have a unique spectral signature that is consistent across multiple manufacturers and construction methods. Solar panels are proven to be detectable in hyperspectral imagery using common statistical target detection methods such as the adaptive cosine estimator, and false alarms can be mitigated through the use of a spectral verification process that eliminates pixels that do not have the key spectral features of photovoltaic solar panel reflectance spectrum. The normalized solar panel index is described and is a key component in the false-alarm mitigation process. After spectral verification, these solar panel arrays are confirmed on openly available literal imagery and can be measured using numerous open-source algorithms and tools. The measurements allow for the assessment of overall solar power generation capacity using an equation that accounts for solar insolation, the area of solar panels, and the efficiency of the solar panels conversion of solar energy to power. Using a known location with readily available information, the methods outlined in this paper estimate the power generation capabilities within 6% of the rated power.

Solar flares, CMEs and solar energetic particle events during solar cycle 24

Science.gov (United States)

Pande, Bimal; Pande, Seema; Chandra, Ramesh; Chandra Mathpal, Mahesh

2018-01-01

We present here a study of Solar Energetic Particle Events (SEPs) associated with solar flares during 2010-2014 in solar cycle 24. We have selected the flare events (≥GOES M-class), which produced SEPs. The SEPs are classified into three categories i.e. weak (proton intensity ≤ 1 pfu), minor (1 pfu pfu) and major (proton intensity ≥ 10 pfu). We used the GOES data for the SEP events which have intensity greater than one pfu and SOHO/ERNE data for the SEP event less than one pfu intensity. In addition to the flare and SEP properties, we have also discussed different properties of associated CMEs.

Solar atmosphere wave dynamics generated by solar global oscillating eigenmodes

Science.gov (United States)

Griffiths, M. K.; Fedun, V.; Erdélyi, R.; Zheng, R.

2018-01-01

The solar atmosphere exhibits a diverse range of wave phenomena, where one of the earliest discovered was the five-minute global acoustic oscillation, also referred to as the p-mode. The analysis of wave propagation in the solar atmosphere may be used as a diagnostic tool to estimate accurately the physical characteristics of the Sun's atmospheric layers. In this paper, we investigate the dynamics and upward propagation of waves which are generated by the solar global eigenmodes. We report on a series of hydrodynamic simulations of a realistically stratified model of the solar atmosphere representing its lower region from the photosphere to low corona. With the objective of modelling atmospheric perturbations, propagating from the photosphere into the chromosphere, transition region and low corona, generated by the photospheric global oscillations the simulations use photospheric drivers mimicking the solar p-modes. The drivers are spatially structured harmonics across the computational box parallel to the solar surface. The drivers perturb the atmosphere at 0.5 Mm above the bottom boundary of the model and are placed coincident with the location of the temperature minimum. A combination of the VALIIIC and McWhirter solar atmospheres are used as the background equilibrium model. We report how synthetic photospheric oscillations may manifest in a magnetic field free model of the quiet Sun. To carry out the simulations, we employed the magnetohydrodynamics code, SMAUG (Sheffield MHD Accelerated Using GPUs). Our results show that the amount of energy propagating into the solar atmosphere is consistent with a model of solar global oscillations described by Taroyan and Erdélyi (2008) using the Klein-Gordon equation. The computed results indicate a power law which is compared to observations reported by Ireland et al. (2015) using data from the Solar Dynamics Observatory/Atmospheric Imaging Assembly.

Solar Schematic

Science.gov (United States)

1979-01-01

The home shown at right is specially designed to accommodate solar heating units; it has roof planes in four directions, allowing placement of solar collectors for best exposure to the sun. Plans (bottom) and complete working blueprints for the solar-heated house are being marketed by Home Building Plan Service, Portland, Oregon. The company also offers an inexpensive schematic (center) showing how a homeowner only moderately skilled in the use of tools can build his own solar energy system, applicable to new or existing structures. The schematic is based upon the design of a low-cost solar home heating system built and tested by NASA's Langley Research Center; used to supplement a warm-air heating system, it can save the homeowner about 40 percent of his annual heating bill for a modest investment in materials and components. Home Building Plan Service saved considerable research time by obtaining a NASA technical report which details the Langley work. The resulting schematic includes construction plans and simplified explanations of solar heat collection, collectors and other components, passive heat factors, domestic hot water supply and how to work with local heating engineers.

Solar panel thermal cycling testing by solar simulation and infrared radiation methods

Science.gov (United States)

Nuss, H. E.

1980-01-01

For the solar panels of the European Space Agency (ESA) satellites OTS/MAROTS and ECS/MARECS the thermal cycling tests were performed by using solar simulation methods. The performance data of two different solar simulators used and the thermal test results are described. The solar simulation thermal cycling tests for the ECS/MARECS solar panels were carried out with the aid of a rotatable multipanel test rig by which simultaneous testing of three solar panels was possible. As an alternative thermal test method, the capability of an infrared radiation method was studied and infrared simulation tests for the ultralight panel and the INTELSAT 5 solar panels were performed. The setup and the characteristics of the infrared radiation unit using a quartz lamp array of approx. 15 sq and LN2-cooled shutter and the thermal test results are presented. The irradiation uniformity, the solar panel temperature distribution, temperature changing rates for both test methods are compared. Results indicate the infrared simulation is an effective solar panel thermal testing method.

Solar Mosaic Inc. Mosaic Home Solar Loan SunShot 9 Final Report

Energy Technology Data Exchange (ETDEWEB)

Walsh, Colin James [Solar Mosaic Inc., Oakland, CA (United States)

2017-02-09

The 6686 Mosaic SunShot award has helped Solar Mosaic Inc to progress from an early stage startup focused on commercial crowdfunding to a leading multi-state residential solar lender. The software platform is now used by the majority of the nation's top solar installers and offers a variety of simple home solar loans. Mosaic is has originated approximately $1Bil in solar loans to date to put solar on over 35k rooftops. The company now lends to homeowners with a wide range of credit scores across multiple states and mitigates boundaries preventing them from profiting from ownership of a home solar system. The project included milestones in 5 main categories: 1. Lending to homeowners outside of CA 2. Lending to homeowners with FICO scores under 700 3. Packaging O&M with the home solar loan 4. Allowing residential installers to process home solar loans via API 5. Lowering customer acquisition costs below $1500 This report includes a detailed review of the final results achieved and key findings.

Idaho | Midmarket Solar Policies in the United States | Solar Research |

Science.gov (United States)

% interest for solar PV projects. Low-interest financing Idaho Energy Resources Authority Solar PV project for financing through the Idaho Governor's Office and the Idaho Energy Resources Authority. Latest -owned community solar project for Idaho Power. Net Metering Idaho does not have statewide net metering

Solar magnetohydrodynamics

International Nuclear Information System (INIS)

Priest, E.R.

1982-01-01

The book serves several purposes. First set of chapters gives a concise general introduction to solar physics. In a second set the basic methods of magnetohydrodynamics are developed. A third set of chapters is an account of current theories for observed phenomena. The book is suitable for a course in solar physics and it also provides a comprehensive review of present magnetohydrodynamical models in solar physics. (SC)

Solar renovation demonstration projects

Energy Technology Data Exchange (ETDEWEB)

Bruun Joergensen, O [ed.

1998-10-01

In the framework of the IEA SHC Programme, a Task on building renovation was initiated, `Task 20, Solar Energy in Building Renovation`. In a part of the task, Subtask C `Design of Solar Renovation Projects`, different solar renovation demonstration projects were developed. The objective of Subtask C was to demonstrate the application of advanced solar renovation concepts on real buildings. This report documents 16 different solar renovation demonstration projects including the design processes of the projects. The projects include the renovation of houses, schools, laboratories, and factories. Several solar techniques were used: building integrated solar collectors, glazed balconies, ventilated solar walls, transparent insulation, second skin facades, daylight elements and photovoltaic systems. These techniques are used in several simple as well as more complex system designs. (au)

Solar neutrinos, helioseismology and the solar internal dynamics

Energy Technology Data Exchange (ETDEWEB)

Turck-Chieze, Sylvaine [Service d' Astrophysique/IRFU/DSM/CEA, 91191 Gif sur Yvette Cedex (France); Couvidat, Sebastien, E-mail: sylvaine.turck-chieze@cea.fr, E-mail: couvidat@stanford.edu [HEPL, Stanford University, Stanford, CA 94305 (United States)

2011-08-15

Neutrinos are fundamental particles ubiquitous in the Universe and whose properties remain elusive despite more than 50 years of intense research activity. This review illustrates the importance of solar neutrinos in astrophysics, nuclear physics and particle physics. After a description of the historical context, we remind the reader of the noticeable properties of these particles and of the stakes of the solar neutrino puzzle. The standard solar model triggered persistent efforts in fundamental physics to predict the solar neutrino fluxes, and its constantly evolving predictions have been regularly compared with the detected neutrino signals. Anticipating that this standard model could not reproduce the internal solar dynamics, a seismic solar model was developed which enriched theoretical neutrino flux predictions with in situ observation of acoustic and gravity waves propagating in the Sun. This seismic model contributed to the stabilization of the neutrino flux predictions. This review recalls the main historical steps, from the pioneering Homestake mine experiment and the GALLEX-SAGE experiments capturing the first proton-proton neutrinos. It emphasizes the importance of the SuperKamiokande and SNO detectors. Both experiments demonstrated that the solar-emitted electron neutrinos are partially transformed into other neutrino flavors before reaching the Earth. This sustained experimental effort opens the door to neutrino astronomy, with long-base lines and underground detectors. The success of BOREXINO in detecting the {sup 7}Be neutrino signal alone instills confidence in physicists' ability to detect each neutrino source separately. It justifies the building of a new generation of detectors to measure the entire solar neutrino spectrum in greater detail, as well as supernova neutrinos. A coherent picture has emerged from neutrino physics and helioseismology. Today, new paradigms take shape in these two fields: neutrinos are massive particles, but their

Updated determination of the solar neutrino fluxes from solar neutrino data

Energy Technology Data Exchange (ETDEWEB)

Bergström, Johannes [Departament d’Estructura i Constituents de la Matèria and Institut de Ciencies del Cosmos,Universitat de Barcelona, Diagonal 647, E-08028 Barcelona (Spain); Gonzalez-Garcia, M. C. [Departament d’Estructura i Constituents de la Matèria and Institut de Ciencies del Cosmos,Universitat de Barcelona, Diagonal 647, E-08028 Barcelona (Spain); Institució Catalana de Recerca i Estudis Avançats (ICREA) (Spain); C.N. Yang Institute for Theoretical Physics,State University of New York at Stony Brook, Stony Brook, NY 11794-3840 (United States); Maltoni, Michele [Instituto de Física Teórica UAM/CSIC,Calle de Nicolás Cabrera 13-15, Universidad Autónoma de Madrid,Cantoblanco, E-28049 Madrid (Spain); Peña-Garay, Carlos [Instituto de Física Corpuscular (IFIC), CSIC and Universitat de Valencia,Calle Catedrático José Beltrán, 2, E-46090 Paterna, Valencia (Spain); Serenelli, Aldo M. [Institut de Ciencies de l’Espai (ICE-CSIC/IEEC),Campus UAB, Carrer de Can Magrans s/n, 08193 Cerdanyola del Valls (Spain); Song, Ningqiang [C.N. Yang Institute for Theoretical Physics,State University of New York at Stony Brook, Stony Brook, NY 11794-3840 (United States)

2016-03-18

We present an update of the determination of the solar neutrino fluxes from a global analysis of the solar and terrestrial neutrino data in the framework of three-neutrino mixing. Using a Bayesian analysis we reconstruct the posterior probability distribution function for the eight normalization parameters of the solar neutrino fluxes plus the relevant masses and mixing, with and without imposing the luminosity constraint. We then use these results to compare the description provided by different Standard Solar Models. Our results show that, at present, both models with low and high metallicity can describe the data with equivalent statistical agreement. We also argue that even with the present experimental precision the solar neutrino data have the potential to improve the accuracy of the solar model predictions.

Solar variability observed through changes in solar figure and mean diameter

International Nuclear Information System (INIS)

Hill, H.A.

1984-01-01

The objective of the project is to detect and monitor climatically significant solar variability by accurate monitoring of the associated variability in solar shape and diameter. The observing program for this project was initiated in 1981. Solar diameter measurements have been taken and data reduction programs for these measurements have been developed. Theoretical analysis of the expected change in the intensity from the solar atmosphere to a given mechanial driving has progressed to the extent that changes in the solar diameter can be related to the associated change in the solar luminosity. An absolute calibration system for the telescope has been constructed and is currently being tested. A proposal is made for the continuation of the work in each of these areas

Solar distillers with mirrors; Destiladores solares con espejos

Energy Technology Data Exchange (ETDEWEB)

Fasulo, A.; Adaro, J.; Marchesi, J.; Follari, J.

2004-07-01

The possibilities to incorporate mirrors to solar distillers are analyzed numerically. We take into account two designs to build the glazing cover, and the two possibilities of orientation of one of these. We determine the quantity of solar radiation that receives each one, for we use it data of hourly radiation, of one year, obtained in the Solar Energy Laboratory. the data are representative of a typical solar year. We obtain a relationship of use of the solar radiation first according to the design of the cover and their orientation. To incorporate mirrors we find that the best strategy, to cover the two designs, they are two mirrors of 50 cm of high for 3m of long such that each one of these they can be guided in independent form. We compare the results with a previous proposal that uses a mirror of 1 m of height, applied one of the orientations. We find the differences and that they give until 74% of increment of the radiation on one of the devices. (Author)

Pilgrimssouvenir

DEFF Research Database (Denmark)

Søvsø, Mette Højmark; Neiß, Michael

2016-01-01

Nye arkæologiske fund af stenstøbeforme fra Ribe viser, at her blev fremstillet religiøse souvenirs i højmiddelalderen. Særligt en af støbeformene er sjælden og spektakulær.......Nye arkæologiske fund af stenstøbeforme fra Ribe viser, at her blev fremstillet religiøse souvenirs i højmiddelalderen. Særligt en af støbeformene er sjælden og spektakulær....

A Vikingek

DEFF Research Database (Denmark)

Roesdahl, Else

Oversættelse til ungarsk af 'The Vikings', revised ed. 1998 (Penguin books), jfr. Vikingernes verden' (Gyldendal 1986, 7. rev. udgave 2001). Oversigt over vikingetidens arkæologi, historie og kultur i Skandinavien og ude i verden.......Oversættelse til ungarsk af 'The Vikings', revised ed. 1998 (Penguin books), jfr. Vikingernes verden' (Gyldendal 1986, 7. rev. udgave 2001). Oversigt over vikingetidens arkæologi, historie og kultur i Skandinavien og ude i verden....

Solar thermal power: the seamless solar link to the conventional power world

International Nuclear Information System (INIS)

Geyer, Michael; Quaschning, Volker

2000-01-01

This article focuses on solar thermal power generation and describes two solar thermal power concepts, namely, the parabolic trough or solar farm, and the solar central receiver or power tower. Details are given of grid-connected parabolic trough power plants in California and recent developments in collector design and absorber tubes, and the operation of power tower plants with different heat transfer media. Market issues are discussed, and solar thermal power projects under development, and application for support for solar thermal power projects under the Global Environment Facility's Operational Programme by Egypt, India, Iran, Mexico and Morocco are reported

Solar Irradiance & On Grid Solar Power Systems with Net Metering in Pakistan

Directory of Open Access Journals (Sweden)

Haleema Qamar

2016-06-01

Full Text Available This paper presents a case study of solar irradiance and scope of on-grid solar power systems with net-metering in Pakistan. Detailed analysis of solar irradiance in Pakistan is being carried out by developing the dedicated solar excel sheets. The need of on grid solar power systems for the present energy crisis in developing countries like Pakistan is also discussed. It also presents the inclination of many countries especially USA and Europe towards it. Identification of barriers for implementing on grid net metered solar power systems in Pakistan along with solutions of these barriers is carried out.

Solar energy in Uruguay. Increase the use of solar panels

International Nuclear Information System (INIS)

Matos, V.

2010-01-01

This article is about the future of the solar energy in Uruguay. The main aspects of this kind of energy are solar thermic which is used for cooking food and heating water through solar collectors as well as the photovoltaics which allows the generation of electricity

Bias-dependent high saturation solar LBIC scanning of solar cells

Energy Technology Data Exchange (ETDEWEB)

Vorster, F.J.; van Dyk, E.E. [Department of Physics, Nelson Mandela Metropolitan University, P.O. Box 77000, Port Elizabeth 6031 (South Africa)

2007-06-15

A light beam-induced current measurement system that uses concentrated solar radiation as a beam probe to map spatially distributed defects on a solar cell has been developed and tested [F.J. Vorster, E.E. van Dyk, Rev. Sci. Instrum., submitted for review]. The induced current response from a flat plate EFG Si solar cell was mapped as a function of surface position and cell bias by using a solar light beam induced current (S-LBIC) mapping system while at the same time dynamically biasing the whole cell with an external voltage. This paper examines the issues relating to transient capacitive effects as well as the electrical behaviour of typical solar cell defect mechanisms under spot illumination. By examining the bias dependence of the S-LBIC maps, various defect mechanisms of photovoltaic (PV) cells under concentrated solar irradiance may be identified. The techniques employed to interpret the spatially distributed IV curves as well as initial results are discussed. (author)

Solar Radius at Subterahertz Frequencies and Its Relation to Solar Activity

Science.gov (United States)

Menezes, Fabian; Valio, Adriana

2017-12-01

The Sun emits radiation at several wavelengths of the electromagnetic spectrum. In the optical band, the solar radius is 695 700 km, and this defines the photosphere, which is the visible surface of the Sun. However, as the altitude increases, the electromagnetic radiation is produced at other frequencies, causing the solar radius to change as a function of wavelength. These measurements enable a better understanding of the solar atmosphere, and the radius dependence on the solar cycle is a good indicator of the changes that occur in the atmospheric structure. We measure the solar radius at the subterahertz frequencies of 0.212 and 0.405 THz, which is the altitude at which these emissions are primarily generated, and also analyze the radius variation over the 11-year solar activity cycle. For this, we used radio maps of the solar disk for the period between 1999 and 2017, reconstructed from daily scans made by the Solar Submillimeter-wave Telescope (SST), installed at El Leoncito Astronomical Complex (CASLEO) in the Argentinean Andes. Our measurements yield radii of 966.5'' ±2.8'' for 0.2 THz and 966.5'' ±2.7'' for 0.4 THz. This implies a height of 5.0 ±2.0 ×106 m above the photosphere. Furthermore, we also observed a strong anticorrelation between the radius variation and the solar activity at both frequencies.

Iowa | Midmarket Solar Policies in the United States | Solar Research |

Science.gov (United States)

Center Solar PV projects are eligible for no-interest financing for up to 50% of the financed project Energy Center administers financing and grant programs for solar photovoltaic (PV) projects. Solar cost (capped at $1,000,000). The Iowa Energy Center also offers several matching grants for project

Solar energy. [New Zealand

Energy Technology Data Exchange (ETDEWEB)

Benseman, R.

1977-10-15

The potential for solar space heating and solar water heating in New Zealand is discussed. Available solar energy in New Zealand is indicated, and the economics of solar space and water heating is considered. (WHK)

Polymethylmethacrylate-based luminescent solar concentrators with bottom-mounted solar cells

International Nuclear Information System (INIS)

Zhang, Yi; Sun, Song; Kang, Rui; Zhang, Jun; Zhang, Ningning; Yan, Wenhao; Xie, Wei; Ding, Jianjun; Bao, Jun; Gao, Chen

2015-01-01

Graphical abstract: - Highlights: • Bottom-mounted luminescent solar concentrators on dye-doped plates were studied. • The mechanism of transport process was proposed. • The fabricated luminescent solar concentrator achieved a gain of 1.38. • Power conversion efficiency of 5.03% was obtained with cell area coverage of 27%. • The lowest cost per watt of $1.89 was optimized with cell area coverage of 18%. - Abstract: Luminescent solar concentrators offer an attractive approach to concentrate sunlight economically without tracking, but the narrow absorption band of luminescent materials hinders their further development. This paper describes bottom-mounted luminescent solar concentrators on dye-doped polymethylmethacrylate plates that absorb not only the waveguided light but also the transmitted sunlight and partial fluorescent light in the escape cone. A series of bottom-mounted luminescent solar concentrators with size of 78 mm × 78 mm × 7 mm were fabricated and their gain and power conversion efficiency were investigated. The transport process of the waveguided light and the relationship between the bottom-mounted cells were studied to optimize the performance of the device. The bottom-mounted luminescent solar concentrator with cell area coverage of 9% displayed a cell gain of 1.38, to our best knowledge, which is the highest value for dye-doped polymethylmethacrylate plate luminescent solar concentrators. Power conversion efficiency as high as 5.03% was obtained with cell area coverage of 27%. Furthermore, the bottom-mounted luminescent solar concentrator was found to have a lowest cost per watt of $1.89 with cell area coverage of 18%. These results suggested that the fabricated bottom-mounted luminescent solar concentrator may have a potential in low-cost building integrated photovoltaic application

Solar maximum mission

International Nuclear Information System (INIS)

Ryan, J.

1981-01-01

By understanding the sun, astrophysicists hope to expand this knowledge to understanding other stars. To study the sun, NASA launched a satellite on February 14, 1980. The project is named the Solar Maximum Mission (SMM). The satellite conducted detailed observations of the sun in collaboration with other satellites and ground-based optical and radio observations until its failure 10 months into the mission. The main objective of the SMM was to investigate one aspect of solar activity: solar flares. A brief description of the flare mechanism is given. The SMM satellite was valuable in providing information on where and how a solar flare occurs. A sequence of photographs of a solar flare taken from SMM satellite shows how a solar flare develops in a particular layer of the solar atmosphere. Two flares especially suitable for detailed observations by a joint effort occurred on April 30 and May 21 of 1980. These flares and observations of the flares are discussed. Also discussed are significant discoveries made by individual experiments

Texas Solar Collaboration DOE Rooftop Solar Challenge City of Houston Project Summary

Energy Technology Data Exchange (ETDEWEB)

Ronk, Jennifer [Houston Advanced Research Center, TX (United States)

2013-02-14

The City of Houston is committed to achieving a sustainable solar infrastructure. In 2008, Houston was named a United States Department of Energy (DOE) Solar America City. As a Solar America City, Houston teamed with the Houston Advanced Research Center (HARC), Sandia National Laboratory (Sandia), industry, and academia, to implement the Solar Houston Initiative and prepare the Solar Houston Plan. The Solar Houston initiative was focused on identifying and overcoming barriers associated with establishing a solar infrastructure that is incorporated into the City of Houston’s overall energy plan. A broad group of Houston area stakeholders, facilitated by HARC, came together to develop a comprehensive solar plan that went beyond technology to address barriers and establish demonstrations, public outreach, education programs and other activities. The plan included proposed scopes of work in four program areas: policies, solar integration, public outreach, and education. Through the support of the DOE SunShot Rooftop Solar Challenge (RSC) grant to the Texas Collaboration (San Antonio, Austin, and Hosuton), Houston has been able to implement several of the recommendations of the Solar Houston Plan. Specific recommendations that this project was able to support include; Working with the other Texas Solar America Cities (San Antonio and Austin), to harmonize permitting and inspection processes to simplify for installers and lower soft costs of installation; Participating in state level solar policy groups such as the Texas Renewable Energy Industries Association (TRIEA); Continued coordination with the local transmission and distribution utility (CenterPoint) and retail electric providers (REP); Identification of opportunities to improve permitting and interconnection; Providing training on PV systems to City inspectors; Educating the public by continuing outreach, training, and workshops, particularly using the the Green Building Resources Center; Evaluating methods of

Solar Pumping : The Basics

OpenAIRE

World Bank Group

2018-01-01

Solar photovoltaic water pumping (SWP) uses energy from solar photovoltaic (PV) panels to power an electric water pump. The entire process, from sunlight to stored energy, is elegant and simple. Over last seven years, the technology and price of solar pumping have evolved dramatically and hence the opportunities it presents. Solar pumping is most competitive in regions with high solar inso...

Solar thermal aircraft

Science.gov (United States)

Bennett, Charles L.

2007-09-18

A solar thermal powered aircraft powered by heat energy from the sun. A heat engine, such as a Stirling engine, is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller. The heat engine has a thermal battery in thermal contact with it so that heat is supplied from the thermal battery. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the sun based on a determination by the heliostat.

Transient flows of the solar wind associated with small-scale solar activity in solar minimum

Science.gov (United States)

Slemzin, Vladimir; Veselovsky, Igor; Kuzin, Sergey; Gburek, Szymon; Ulyanov, Artyom; Kirichenko, Alexey; Shugay, Yulia; Goryaev, Farid

The data obtained by the modern high sensitive EUV-XUV telescopes and photometers such as CORONAS-Photon/TESIS and SPHINX, STEREO/EUVI, PROBA2/SWAP, SDO/AIA provide good possibilities for studying small-scale solar activity (SSA), which is supposed to play an important role in heating of the corona and producing transient flows of the solar wind. During the recent unusually weak solar minimum, a large number of SSA events, such as week solar flares, small CMEs and CME-like flows were observed and recorded in the databases of flares (STEREO, SWAP, SPHINX) and CMEs (LASCO, CACTUS). On the other hand, the solar wind data obtained in this period by ACE, Wind, STEREO contain signatures of transient ICME-like structures which have shorter duration (<10h), weaker magnetic field strength (<10 nT) and lower proton temperature than usual ICMEs. To verify the assumption that ICME-like transients may be associated with the SSA events we investigated the number of weak flares of C-class and lower detected by SPHINX in 2009 and STEREO/EUVI in 2010. The flares were classified on temperature and emission measure using the diagnostic means of SPHINX and Hinode/EIS and were confronted with the parameters of the solar wind (velocity, density, ion composition and temperature, magnetic field, pitch angle distribution of the suprathermal electrons). The outflows of plasma associated with the flares were identified by their coronal signatures - CMEs (only in few cases) and dimmings. It was found that the mean parameters of the solar wind projected to the source surface for the times of the studied flares were typical for the ICME-like transients. The results support the suggestion that weak flares can be indicators of sources of transient plasma flows contributing to the slow solar wind at solar minimum, although these flows may be too weak to be considered as separate CMEs and ICMEs. The research leading to these results has received funding from the European Union’s Seventh Programme

Design and Development of a Solar Thermal Collector with Single Axis Solar Tracking Mechanism

Directory of Open Access Journals (Sweden)

Theebhan Mogana

2016-01-01

Full Text Available The solar energy is a source of energy that is abundant in Malaysia and can be easily harvested. However, because of the rotation of the Earth about its axis, it is impossible to harvest the solar energy to the maximum capacity if the solar thermal collector is placed fix to a certain angle. In this research, a solar thermal dish with single axis solar tracking mechanism that will rotate the dish according to the position of the sun in the sky is designed and developed, so that more solar rays can be reflected to a focal point and solar thermal energy can be harvested from the focal point. Data were collected for different weather conditions and performance of the solar thermal collector with a solar tracker were studied and compared with stationary solar thermal collector.

Seguidor Solar, optimizando el aprovechamiento de la energía solar ; Solar tracker, optimizing ofimprovementof the solar energy

Directory of Open Access Journals (Sweden)

Noel Machado Toranzo

2015-06-01

Full Text Available En este trabajo se realizó el diseño e implementación de un dispositivo encargado de obtener las coordenadas del Sol en cualquier momento del día, es decir, un seguidor solar a dos ejes por punto luminoso. Este seguidor consta de dos bloques principales: la tarjeta controladora y la parte mecánica. Su diseño se basó en el uso de fotorresistencias, microcontroladores y motores de pasos, el mismo posee altas prestaciones y bajo costo. El prototipo construido es utilizado en las investigaciones de aprovechamiento de la energía solar que se realizan en el Grupo de Energía Renovable Aplicadas (GERA de la Universidad de Oriente, particularmente en los paneles fotovoltaicos y los calentadores de agua. Se realizó una prueba experimental en los laboratorios y en el polígono de dicho grupo y se comprobó que el seguidor solar funciona adecuadamente, cumpliendo con las expectativas deseadas.The design and implementation of a device for obtaining the coordinates of the sun at any time during the day, it means, a solar tracker of type two axis by luminous point is developed in this paper. This tracker consists of two main blocks: the controller board and the mechanical part. The design is based on the use of photoresistences, microcontrollers and stepper motors. The prototype is used on investigations about solar energy developed at the GERA (Grupo de Energía Renovable Aplicada of Universidad de Oriente, particularly in photovoltaic panels and water heaters. An experimental test was conducted in the laboratories and at the site of the group and it was found that the solar tracker is functioning properly, meeting the desired expectations.

Solar Irradiance Variability is Caused by the Magnetic Activity on the Solar Surface.

Science.gov (United States)

Yeo, Kok Leng; Solanki, Sami K; Norris, Charlotte M; Beeck, Benjamin; Unruh, Yvonne C; Krivova, Natalie A

2017-09-01

The variation in the radiative output of the Sun, described in terms of solar irradiance, is important to climatology. A common assumption is that solar irradiance variability is driven by its surface magnetism. Verifying this assumption has, however, been hampered by the fact that models of solar irradiance variability based on solar surface magnetism have to be calibrated to observed variability. Making use of realistic three-dimensional magnetohydrodynamic simulations of the solar atmosphere and state-of-the-art solar magnetograms from the Solar Dynamics Observatory, we present a model of total solar irradiance (TSI) that does not require any such calibration. In doing so, the modeled irradiance variability is entirely independent of the observational record. (The absolute level is calibrated to the TSI record from the Total Irradiance Monitor.) The model replicates 95% of the observed variability between April 2010 and July 2016, leaving little scope for alternative drivers of solar irradiance variability at least over the time scales examined (days to years).

Evolution of the solar system in the presence of a solar companion star

International Nuclear Information System (INIS)

Hut, P.

1986-01-01

A review is presented of the dynamical implications of a companion star in a wide orbit around the sun, with a semimajor axis of about half a parsec. The motivation behind the hypothesis of a solar companion star is reviewed briefly along with alternative hypotheses, and the general problem of solar system dynamics with a solar companion star is discussed. Four principal questions are posed and answered concerning the consistency of the solar companion theory in providing the required modulation in comet arrival times: (1) What is the expected lifetime of a solar companion? (2) How stable is the orbital period? (3) Does a single perihelion passage of a solar companion perturb enough comets? (4) Do repeated perihelion passages of a solar companion perturb too many comets? Some applications outside the solar system involving wide binaries, interstellar clouds, and dark matter in the Galactic disk are discussed, and the viability of the solar companion theory is critically assessed

A Preliminary Analysis of Solar Irradiance Measurements at TNB Solar Research Centre for Optimal Orientation of Fixed Solar Panels installed in Selangor Malaysia

International Nuclear Information System (INIS)

Hashim, A M; Ahmad, B; Shafie, R M; Rusli, R; Aziz, M A; Hassan, J; Wanik, M Z C; Ali, M A M

2013-01-01

The well established rule for orienting fixed solar devices is to face south for places in the northern hemisphere and northwards for the southern hemisphere. However for regions near the equator such as in Selangor Malaysia, the position of the sun at solar noon is always near zenith both to the north and south depending on location and month of year. This paper reports an analysis of global solar radiation data taken at TNB Solar Research Centre, Malaysia. The solar radiation is measured using both shaded and exposed pyranometers together with a pyrheliometer which is mounted on a sun-tracker. The analysis on the solar measurements show that a near regular solar irradiation pattern had occurred often enough during the year to recommend an optimum azimuth orientation of installing the fixed solar panels tilted facing towards east. Even though all the solar measurements were done at a single location in TNBR Solar Research Centre at Bangi, for locations near the equator with similar weather pattern, the recommended azimuth direction of installing fixed solar panels and collectors tilted eastward will also be generally valid.

Solar '95: Proceedings of the 20. national passive solar conference. Volume 20

International Nuclear Information System (INIS)

Campbell-Howe, R.; Wilkins-Crowder, B.

1995-01-01

This book contains the proceedings of the 20th National Passive Solar Conference, 1995, of the American Solar Energy Society. The topics of the papers include historical aspects of solar energy, daylighting, examination of passive system designs, sustainability concepts, building components, building design, application of solar architecture, case studies, education, and design tools

Solar variability observed through changes in solar figure and mean diameter

International Nuclear Information System (INIS)

Hill, H.A.

1991-01-01

The work performed on solar variability during 1990 at SCLERA is reviewed. That portion of the SCLERA research program supported by the Department of Energy has been directed toward the detection and monitoring of climatically significant solar variability by accurate measurement of the variability in solar shape and diameter. Observations were obtained in 1990 and results from analysis of earlier observations obtained. The observational evidence of systematic long-term changes in the apparent solar diameter and/or radius has been detected, and these changes continue to strongly correlated with long-term changes in solar total irradiance. Additional evidence for internal gravity modes has been found which may be important to understanding the internal structure of the Sun. Each of these findings shows promise for anticipating future changes in the solar luminosity. Progress has been made in setting up an international network based on SCLERA-type instruments to improve the coverage and quality of the observations. A proposal is made for the continuation of support from the Department of Energy for further studies relevant to solar-variability forecasting

Solar Features

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of solar feature datasets contributed by a number of national and private solar observatories located worldwide.

Effluents treatment by solar photocatalysis; Tratamiento de efluentes con fotocatalisis solar

Energy Technology Data Exchange (ETDEWEB)

Blanco, J; Malato, S; Richter, C [Plataforma Solar de almeria, Almeria (Spain); Carmona, F; Martinez, F [Deretil, Almeria (Spain)

1996-12-31

A solar photocatalytic system is being developed at the Plataforma Solar De Almeria to destroy organic contaminants in water. Test with common water contaminants were conducted at the Solar Detoxification loop with real sun light and large quantities of water flowing through glass tubes were the solar UV light is concentrated. Experiments at this scale provide verification of laboratory studies and allow the design and operation of real preindustrial detoxification systems. (Author)

Kinetic Physics of the Solar Corona and Solar Wind

Directory of Open Access Journals (Sweden)

Marsch Eckart

2006-07-01

Full Text Available Kinetic plasma physics of the solar corona and solar wind are reviewed with emphasis on the theoretical understanding of the in situ measurements of solar wind particles and waves, as well as on the remote-sensing observations of the solar corona made by means of ultraviolet spectroscopy and imaging. In order to explain coronal and interplanetary heating, the microphysics of the dissipation of various forms of mechanical, electric and magnetic energy at small scales (e.g., contained in plasma waves, turbulences or non-uniform flows must be addressed. We therefore scrutinise the basic assumptions underlying the classical transport theory and the related collisional heating rates, and also describe alternatives associated with wave-particle interactions. We elucidate the kinetic aspects of heating the solar corona and interplanetary plasma through Landau- and cyclotron-resonant damping of plasma waves, and analyse in detail wave absorption and micro instabilities. Important aspects (virtues and limitations of fluid models, either single- and multi-species or magnetohydrodynamic and multi-moment models, for coronal heating and solar wind acceleration are critically discussed. Also, kinetic model results which were recently obtained by numerically solving the Vlasov–Boltzmann equation in a coronal funnel and hole are presented. Promising areas and perspectives for future research are outlined finally.

From Solar Cookers Towards Viable Solar Cooking Technology

DEFF Research Database (Denmark)

Ahmad, Bashir

1997-01-01

A broader concept of technology encompassing the technical and the societal aspects is introduced. Viability of technology and technological development process from a socio-technical view- point is discussed. Based on the above, the question of securing viability of solar cooking technology...... is taken up. It is discussed that actor- approach can operationally relate the abstract societal factors with those of technical aspects. Some concrete measures regarding application of solar cooker projects are drawn from the discussion: solar cooking projects should a) be based on user and producer...

GPP Webinar: The Solar Roadmap—Navigating the Evolving Solar Energy Market

Science.gov (United States)

GPP and State & Local Climate and Energy Branch webinar on the Solar Roadmap and the evolving solar energy market. This webinar discussed local and state government’s success stories and opportunities for progress in renewable energy goals using the Solar

Comparison of Artificial Neural Networks and GIS Based Solar Analysis for Solar Potential Estimation

Science.gov (United States)

Konakoǧlu, Berkant; Usta, Ziya; Cömert, Çetin; Gökalp, Ertan

2016-04-01

Nowadays, estimation of solar potential plays an important role in planning process for sustainable cities. The use of solar panels, which produces electricity directly from the sun, has become popular in accordance with developing technologies. Since the use of solar panels enables the users to decrease costs and increase yields, the use of solar panels will be more popular in the future. Production of electricity is not convenient for all circumstances. Shading effects, massive clouds and rainy weather are some factors that directly affect the production of electricity from solar energy. Hence, before the installation of solar panels, it is crucial to conduct spatial analysis and estimate the solar potential of the place that the solar panel will be installed. There are several approaches to determine the solar potential. Examination of the applications in the literature reveals that the applications conducted for determining the solar potential are divided into two main categories. Solar potential is estimated either by using artificial neural network approach in which statistical parameters such as the duration of sun shine, number of clear days, solar radiation etc. are used, or by spatial analysis conducted in GIS approaches in which spatial parameters such as, latitude, longitude, slope, aspect etc. are used. In the literature, there are several studies that use both approaches but the literature lacks of a study related to the comparison of these approaches. In this study, Karadeniz Technical University campus has been selected as study area. Monthly average values of the number of clear sky days, air temperature, atmospheric pressure, relative humidity, sunshine duration and solar radiation parameters obtained for the years between 2005 and 2015 will be used to perform artificial neural network analysis to estimate the solar potential of the study area. The solar potential will also be estimated by using GIS-based solar analysis modules. The results of

Solar Photovoltaic Cells.

Science.gov (United States)

Mickey, Charles D.

1981-01-01

Reviews information on solar radiation as an energy source. Discusses these topics: the key photovoltaic material; the bank theory of solids; conductors, semiconductors, and insulators; impurity semiconductors; solid-state photovoltaic cell operation; limitations on solar cell efficiency; silicon solar cells; cadmium sulfide/copper (I) sulfide…

Solar Photovoltaic

OpenAIRE

Wang, Chen; Lu, Yuefeng

2016-01-01

In the 21st century, human demand for new energy sources is urgent, because the traditional fossil energy is unable to meet human needs, and the fossil resource will make pollution, in this situation, solar energy gradually into the vision of scientists. As science advances, humans can already extensive use of solar energy to generate electricity. Solar energy is an inexhaustible and clean energy. In the global energy crisis, environmental pollution is the growing problem of today. The us...

Solar Imagery

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of solar photographic and illustrated datasets contributed by a number of national and private solar observatories located worldwide....

Solar weather monitoring

Directory of Open Access Journals (Sweden)

J.-F. Hochedez

2005-11-01

Full Text Available Space Weather nowcasting and forecasting require solar observations because geoeffective disturbances can arise from three types of solar phenomena: coronal mass ejections (CMEs, flares and coronal holes. For each, we discuss their definition and review their precursors in terms of remote sensing and in-situ observations. The objectives of Space Weather require some specific instrumental features, which we list using the experience gained from the daily operations of the Solar Influences Data analysis Centre (SIDC at the Royal Observatory of Belgium. Nowcasting requires real-time monitoring to assess quickly and reliably the severity of any potentially geoeffective solar event. Both research and forecasting could incorporate more observations in order to feed case studies and data assimilation respectively. Numerical models will result in better predictions of geomagnetic storms and solar energetic particle (SEP events. We review the data types available to monitor solar activity and interplanetary conditions. They come from space missions and ground observatories and range from sequences of dopplergrams, magnetograms, white-light, chromospheric, coronal, coronagraphic and radio images, to irradiance and in-situ time-series. Their role is summarized together with indications about current and future solar monitoring instruments.

Solar-hydrogen generation and solar concentration (Conference Presentation)

NARCIS (Netherlands)

Sulima, Oleg V.; Chinello, Enrico; Conibeer, Gavin; Modestino, Miquel A.; Schüttauf, Jan-Willem; Lambelet, David; Delfino, Antonio; Domine, Didier; Faes, Antonin; Despeisse, Matthieu; Bailat, Julien; Psaltis, Demetri; Fernandez Rivas, David; Ballif, Christophe; Moser, Christophe

2016-01-01

We successfully demonstrated and reported the highest solar-to-hydrogen efficiency with crystalline silicon cells and Earth-abundant electrocatalysts under unconcentrated solar radiation. The combination of hetero-junction silicon cells and a 3D printed Platinum/Iridium-Oxide electrolyzer has been

Measuring Solar Radiation Incident on Earth: Solar Constant-3 (SOLCON-3)

Science.gov (United States)

Crommelynck, Dominique; Joukoff, Alexandre; Dewitte, Steven

2002-01-01

Life on Earth is possible because the climate conditions on Earth are relatively mild. One element of the climate on Earth, the temperature, is determined by the heat exchanges between the Earth and its surroundings, outer space. The heat exchanges take place in the form of electromagnetic radiation. The Earth gains energy because it absorbs solar radiation, and it loses energy because it emits thermal infrared radiation to cold space. The heat exchanges are in balance: the heat gained by the Earth through solar radiation equals the heat lost through thermal radiation. When the balance is perturbed, a temperature change and hence a climate change of the Earth will occur. One possible perturbation of the balance is the CO2 greenhouse effect: when the amount of CO2 in the atmosphere increases, this will reduce the loss of thermal infrared radiation to cold space. Earth will gain more heat and hence the temperature will rise. Another perturbation of the balance can occur through variation of the amount of energy emitted by the sun. When the sun emits more energy, this will directly cause a rise of temperature on Earth. For a long time scientists believed that the energy emitted by the sun was constant. The 'solar constant' is defined as the amount of solar energy received per unit surface at a distance of one astronomical unit (the average distance of Earth's orbit) from the sun. Accurate measurements of the variations of the solar constant have been made since 1978. From these we know that the solar constant varies approximately with the 11-year solar cycle observed in other solar phenomena, such as the occurrence of sunspots, dark spots that are sometimes visible on the solar surface. When a sunspot occurs on the sun, since the spot is dark, the radiation (light) emitted by the sun drops instantaneously. Oddly, periods of high solar activity, when a lot of sunspot numbers increase, correspond to periods when the average solar constant is high. This indicates that

Solar Research | NREL

Science.gov (United States)

Research Photo of a city landscape with a sun in the background. Solar energy research at NREL includes photovoltaics, concentrating solar power, solar grid and systems integration, and market research and analysis. Photovoltaic Research Photo of a roof-mounted PV array on the NREL campus. NREL's

Solar Indices

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

Solar heating and cooling.

Science.gov (United States)

Duffie, J A

1976-01-01

Solar energy is discussed as an energy resource that can be converted into useful energy forms to meet a variety of energy needs. The review briefly explains the nature of this energy resource, the kinds of applications that can be made useful, and the status of several systems to which it has been applied. More specifically, information on solar collectors, solar water heating, solar heating of buildings, solar cooling plus other applications, are included.

Midmarket Solar Policies in the United States: A Guide for Midsized Solar Customers

Energy Technology Data Exchange (ETDEWEB)

Tian, Tian [National Renewable Energy Lab. (NREL), Golden, CO (United States); Liu, Chang [National Renewable Energy Lab. (NREL), Golden, CO (United States); O' Shaughnessy, Eric [National Renewable Energy Lab. (NREL), Golden, CO (United States); Mathur, Shivani [National Renewable Energy Lab. (NREL), Golden, CO (United States); Holm, Alison [National Renewable Energy Lab. (NREL), Golden, CO (United States); Miller, John [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-09-01

The midscale market for solar photovoltaics (PV) has not experienced the same high growth rate as residential- or utility-scale market segments in the past five years when solar PV deployment increased rapidly. Midscale solar can be defined as behind-the-meter solar PV between 50 kilowatts and 2 megawatts adopted by multi-housing residential, commercial, industrial, non-profit, and other entities. A number of challenges face the midscale segment, including difficulties in contracting, mismatch between tenant lease and PV financing terms, high transaction costs relative to project sizes, and inefficiencies in matching prospective projects with capital. The changing policy landscape across U.S. states provides both opportunities and challenges to midmarket solar. Some states, such as California, are expanding system capacity limits for policies such as net metering, thus enabling a wider range of customers to benefit from excess generation. A number of states and utilities are making changes to rate design to introduce new or higher user fees for solar customers or reduced tariffs for net metering, which decrease the value of solar generation. An understanding of these policies relative to project feasibility and economics is important for prospective customers to make informed decisions to adopt solar PV. This guide complements existing solar policy resources to help potential customers navigate through the policy landscape in order to make informed decisions for their solar investment. The first part of this guide introduces the key solar policies necessary for policy-based decision-making, which involves using knowledge of a solar policy to improve project economics and efficiency. Policies that could result in policy-based decisions include interconnection standards, net metering, user fees, incentives, and third-party ownership policies. The goal of this section is to equip prospective customers and project developers with the tools necessary to understand and

Solar Flares and the High Energy Solar Spectroscopic Imager (HESSI)

Science.gov (United States)

Holman, Gordon D.; Fisher, Richard R. (Technical Monitor)

2001-01-01

Solar flares are the biggest explosions in the solar system. They are important both for understanding explosive events in the Universe and for their impact on human technology and communications. The satellite-based HESSI is designed to study the explosive release of energy and the acceleration of electrons, protons, and other charged particles to high energies in solar flares. HESSI produces "color" movies of the Sun in high-energy X rays and gamma rays radiated by these energetic particles. HESSI's X-ray and gamma-ray images of flares are obtained using techniques similar to those used in radio interferometry. Ground-based radio observations of the Sun provide an important complement to the HESSI observations of solar flares. I will describe the HESSI Project and the high-energy aspects of solar flares, and how these relate to radio astronomy techniques and observations.

The SOLAR-C Mission

Science.gov (United States)

Suematsu, Y.

2015-12-01

The Solar-C is a Japan-led international solar mission planned to be launched in mid2020. It is designed to investigate the magnetic activities of the Sun, focusing on the study in heating and dynamical phenomena of the chromosphere and corona, and also to develop an algorithm for predicting short and long term solar evolution. Since it has been revealed that the different parts of the magnetized solar atmosphere are essentially coupled, the SOLAR-C should tackle the spatial scales and temperature regimes that need to be observed in order to achieve a comprehensive physical understanding of this coupling. The science of Solar-C will greatly advance our understanding of the Sun, of basic physical processes operating throughout the universe. To dramatically improve the situation, SOLAR-C will carry three dedicated instruments; the Solar UV-Vis-IR Telescope (SUVIT), the EUV Spectroscopic Telescope (EUVST) and the High Resolution Coronal Imager (HCI), to jointly observe the entire visible solar atmosphere with essentially the same high spatial resolution (0.1-0.3 arcsec), performing high resolution spectroscopic measurements over all atmospheric regions and spectro-polarimetric measurements from the photosphere through the upper chromosphere. In addition, Solar-C will contribute to our understanding on the influence of the Sun-Earth environments with synergetic wide-field observations from ground-based and other space missions. Some leading science objectives and the mission concept, including designs of the three instruments aboard SOLAR-C will be presented.

Solar thermal and concentrated solar power barometer

International Nuclear Information System (INIS)

2013-01-01

The European concentrated solar power plant market is steeling itself for tough time ahead. The number of projects under construction is a pittance compared with 2012 that was an excellent year for installations (an additional 802.5 MW of capacity recorded). This drop is the result of the moratorium on renewable energy power plants introduced by the Spanish government. The European solar thermal market is hardly any more encouraging . EurObserv'ER holds that it slipped for the fourth year in a row (it dropped 5.5% between 2011 and 2012). The newly-installed solar thermal collector surface area in the EU now stands at 3.4 million m 2 , far short of its 2008 installation record of 4.6 million m 2 . The EU's solar thermal base to date at the end of 2012 is 29.6 GWth with 2.4 GWth installed during the year 2012. This article gives tables gathering the figures of the production for every European country for 2012 and describes the market and the general trend for every EU member

Solar energy: a UK assessment

Energy Technology Data Exchange (ETDEWEB)

1976-01-01

A panel convened by UK-ISES to analyze all aspects of solar energy systems and to assess the potential for solar energy utilization and research and development needs in the UK and for export is reported. Topics covered include: solar energy in relation to other energy sources; international solar energy research and development program; the physical nature of solar energy and its availability in the UK and other countries; thermal collection, storage, and low-temperature applications; solar energy and architecture; solar thermal power systems; solar cells; agricultural and biological systems; photochemical systems; social, legal, and political considerations with particular reference to the UK; and future policy on solar research and development for the UK. (WDM)

Manifestation of solar activity in solar wind particle flux density

International Nuclear Information System (INIS)

Kovalenko, V.A.

1988-01-01

An analysis has been made of the origin of long-term variations in flux density of solar wind particles (nv) for different velocity regimes. The study revealed a relationship of these variations to the area of the polar coronal holes (CH). It is shown that within the framework of the model under development, the main longterm variations of nv are a result of the latitude redistribution of the solar wind mass flux in the heliosphere and are due to changes in the large-scale geometry of the solar plasma flow in the corona. A study has been made of the variations of nv for high speed solar wind streams. It is found that nv in high speed streams which are formed in CH, decreases from minimum to maximum solar activity. The analysis indicates that this decrease is attributable to the magnetic field strength increase in coronal holes. It has been found that periods of rapid global changes of background magnetic fields on the Sun are accompanied by a reconfiguration of coronal magnetic fields, rapid changes in the length of quiescent filaments, and by an increase in the density of the particle flux of a high speed solar wind. It has been established that these periods precede the formation of CH, corresponding to the increase in solar wind velocity near the Earth and to enhancement of the level of geomagnetic disturbance. (author)

A comparison of solar wind streams and coronal structure near solar minimum

Science.gov (United States)

Nolte, J. T.; Davis, J. M.; Gerassimenko, M.; Lazarus, A. J.; Sullivan, J. D.

1977-01-01

Solar wind data from the MIT detectors on the IMP 7 and 8 satellites and the SOLRAD 11B satellite for the solar-minimum period September-December, 1976, were compared with X-ray images of the solar corona taken by rocket-borne telescopes on September 16 and November 17, 1976. There was no compelling evidence that a coronal hole was the source of any high speed stream. Thus it is possible that either coronal holes were not the sources of all recurrent high-speed solar wind streams during the declining phase of the solar cycle, as might be inferred from the Skylab period, or there was a change in the appearance of some magnetic field regions near the time of solar minimum.

Solar Energy Perspectives In Egypt

International Nuclear Information System (INIS)

Comsan, M.N.H.

2010-01-01

Egypt belongs to the global sun-belt. The country is in advantageous position with solar energy. In 1991 solar atlas for Egypt was issued indicating that the country enjoys 2900-3200 hours of sunshine annually with annual direct normal energy density 1970-3200 kWh/m2 and technical solar-thermal electricity generating potential of 73.6 Peta watt hour (PWh). Egypt was among the first countries to utilize solar energy. In 1910, a practical industrial scale solar system engine was built at Maadi south to Cairo using solar thermal parabolic collectors. The engine was used to produce steam which drove a series of large water pumps for irrigation. Nowadays utilization of solar energy includes use of photovoltaic cells, solar water heating and solar thermal power. Use of solar thermal technology may include both electricity generation and water desalination, which is advantageous for Egypt taking in consideration its shortage in water supply. The article discusses perspectives of solar energy in Egypt and developmental trends till 2050

Rectenna solar cells

CERN Document Server

Moddel, Garret

2013-01-01

Rectenna Solar Cells discusses antenna-coupled diode solar cells, an emerging technology that has the potential to provide ultra-high efficiency, low-cost solar energy conversion. This book will provide an overview of solar rectennas, and provide thorough descriptions of the two main components: the diode, and the optical antenna. The editors discuss the science, design, modeling, and manufacturing of the antennas coupled with the diodes. The book will provide concepts to understanding the challenges, fabrication technologies, and materials required to develop rectenna structures. Written by e

Solar and Hydrogen

International Nuclear Information System (INIS)

Kadirgan, F.; Beyhan, S.; Oezenler, S.

2006-01-01

It has been widely accepted that the only sustainable and environmentally friendly energy is the solar energy and hydrogen energy, which can meet the increasing energy demand in the future. Solar Energy may be used either for solar thermal or for solar electricity conversion. Solar thermal collectors represent a wide-spread type of system for the conversion of solar energy. Radiation, convection and conduction are strongly coupled energy transport mechanisms in solar collector systems. The economic viability of lower temperature applications of solar energy may be improved by increasing the quantity of usable energy delivered per unit area of collector. This can be achieved by the use of selective black coatings which have a high degree of solar absorption, maintaining high energy input to the solar system while simultaneously suppressing the emission of thermal infrared radiation. Photovoltaic solar cells and modules are produced for: (1) large scale power generation, most commonly when modules are incorporated as part of a building (building integrated photovoltaic s) but also in centralised power stations, (2) supplying power to villages and towns in developing countries that are not connected to the supply grid, e.g. for lighting and water pumping systems, (3) supplying power in remote locations, e.g. for communications or weather monitoring equipment, (4) supplying power for satellites and space vehicles, (5) supplying power for consumer products, e.g. calculators, clocks, toys and night lights. In hydrogen energy systems, Proton exchange membrane (PEMFC) fuel cells are promising candidates for applications ranging from portable power sources (battery replacement applications) to power sources for future electric vehicles because of their safety, elimination of fuel processor system, thus, simple device fabrication and low cost. Although major steps forward have been achieved in terms of PEMFC design since the onset of research in this area, further

Semiconductor-based Multilayer Selective Solar Absorber for Unconcentrated Solar Thermal Energy Conversion.

Science.gov (United States)

Thomas, Nathan H; Chen, Zhen; Fan, Shanhui; Minnich, Austin J

2017-07-13

Solar thermal energy conversion has attracted substantial renewed interest due to its applications in industrial heating, air conditioning, and electricity generation. Achieving stagnation temperatures exceeding 200 °C, pertinent to these technologies, with unconcentrated sunlight requires spectrally selective absorbers with exceptionally low emissivity in the thermal wavelength range and high visible absorptivity for the solar spectrum. In this Communication, we report a semiconductor-based multilayer selective absorber that exploits the sharp drop in optical absorption at the bandgap energy to achieve a measured absorptance of 76% at solar wavelengths and a low emittance of approximately 5% at thermal wavelengths. In field tests, we obtain a peak temperature of 225 °C, comparable to that achieved with state-of-the-art selective surfaces. With straightforward optimization to improve solar absorption, our work shows the potential for unconcentrated solar thermal systems to reach stagnation temperatures exceeding 300 °C, thereby eliminating the need for solar concentrators for mid-temperature solar applications such as supplying process heat.

The Solar Wind from Pseudostreamers and their Environs: Opportunities for Observations with Parker Solar Probe and Solar Orbiter

Science.gov (United States)

Panasenco, O.; Velli, M.; Panasenco, A.; Lionello, R.

2017-12-01

The solar dynamo and photospheric convection lead to three main types of structures extending from the solar surface into the corona - active regions, solar filaments (prominences when observed at the limb) and coronal holes. These structures exist over a wide range of scales, and are interlinked with each other in evolution and dynamics. Active regions can form clusters of magnetic activity and the strongest overlie sunspots. In the decay of active regions, the boundaries separating opposite magnetic polarities (neutral lines) develop specific structures called filament channels above which filaments form. In the presence of flux imbalance decaying active regions can also give birth to lower latitude coronal holes. The accumulation of magnetic flux at coronal hole boundaries also creates conditions for filament formation: polar crown filaments are permanently present at the boundaries of the polar coronal holes. Mid-latitude and equatorial coronal holes - the result of active region evolution - can create pseudostreamers if other coronal holes of the same polarity are present. While helmet streamers form between open fields of opposite polarities, the pseudostreamer, characterized by a smaller coronal imprint, typically shows a more prominent straight ray or stalk extending from the corona. The pseudostreamer base at photospheric heights is multipolar; often one observes tripolar magnetic configurations with two neutral lines - where filaments can form - separating the coronal holes. Here we discuss the specific role of filament channels on pseudostreamer topology and on solar wind properties. 1D numerical analysis of pseudostreamers shows that the properties of the solar wind from around PSs depend on the presence/absence of filament channels, number of channels and chirality at thepseudostreamer base low in the corona. We review and model possible coronal magnetic configurations and solar wind plasma properties at different distances from the solar surface that

Magnetohydrodynamic process in solar activity

Directory of Open Access Journals (Sweden)

Jingxiu Wang

2014-01-01

Full Text Available Magnetohydrodynamics is one of the major disciplines in solar physics. Vigorous magnetohydrodynamic process is taking place in the solar convection zone and atmosphere. It controls the generating and structuring of the solar magnetic fields, causes the accumulation of magnetic non-potential energy in the solar atmosphere and triggers the explosive magnetic energy release, manifested as violent solar flares and coronal mass ejections. Nowadays detailed observations in solar astrophysics from space and on the ground urge a great need for the studies of magnetohydrodynamics and plasma physics to achieve better understanding of the mechanism or mechanisms of solar activity. On the other hand, the spectacular solar activity always serves as a great laboratory of magnetohydrodynamics. In this article, we reviewed a few key unresolved problems in solar activity studies and discussed the relevant issues in solar magnetohydrodynamics.

Large-scale solar purchasing

International Nuclear Information System (INIS)

1999-01-01

The principal objective of the project was to participate in the definition of a new IEA task concerning solar procurement (''the Task'') and to assess whether involvement in the task would be in the interest of the UK active solar heating industry. The project also aimed to assess the importance of large scale solar purchasing to UK active solar heating market development and to evaluate the level of interest in large scale solar purchasing amongst potential large scale purchasers (in particular housing associations and housing developers). A further aim of the project was to consider means of stimulating large scale active solar heating purchasing activity within the UK. (author)

Elemental composition and ionization state of the solar atmosphere and solar wind

International Nuclear Information System (INIS)

Joselyn, J.A.C.

1978-01-01

Abundance measurements have always proved useful in generating and refining astrophysical theories. Some of the classical problems of astrophysics involve determining the relative abundances of elements in the atmosphere of a star from observations of its line spectrum, and then synthesizing the physical processes which would produce such abundances. Theories of the formation of the solar system are critically tested by their ability to explain observed abundances, and, elemental abundances can serve as tracers, helping to determine the origin and transport of ions. Since the solar wind originates at the sun, it can act as a diagnostic probe of solar conditions. In particular, measurements of the composition of the solar wind should be related to the solar composition. And, assuming ionization equilibrium, measurements of the relative abundances of the ionization states in the solar wind should infer coronal temperatures and temperature gradients. However, most spherically symmetric models of the solar wind are unable to explain the relationship between the composition estimated from solar observations and as measured at 1 AU; and, recent observations of significant flow speeds in the transition region raise doubts about the validity of the assumption of ionization equilibrium

Solar-system Education for the 2017 Total Solar Eclipse

Science.gov (United States)

Pasachoff, Jay M.

2017-10-01

I describe an extensive outreach program about the Sun, the silhouette of the Moon, and the circumstances both celestial and terrestrial of the August 21, 2017, total solar eclipse. Publications included a summary of the last decade of solar-eclipse research for Nature Astronomy, a Resource Letter on Observing Solar Eclipses for the American Journal of Physics, and book reviews for Nature and for Phi Beta Kappa's Key Reporter. Symposia arranged include sessions at AAS, APS, AGU, and AAAS. Lectures include all ages from pre-school through elementary school to high school to senior-citizen residences. The work, including the scientific research about the solar corona that is not part of this abstract, was supported by grants from the Solar Terrestrial Program of the Atmospheric and Geospace Sciences Division of NSF and from the Committee for Research and Exploration of the National Geographic Society. Additional student support was received from NSF, NASA's Massachusetts Space Grant Consortium, the Honorary Research Society Sigma Xi, the Clare Booth Luce Foundation, and funds at Williams College.

Excel-ark i mudderet

DEFF Research Database (Denmark)

Thorsted, Thomas; Brinch Jensen, Kenneth; Grøn, Maria Christine

2014-01-01

Det er svært at forestille sig et mere turbulent miljø at operere i end det, som madboderne på Roskilde Festival kaster sig ud i de 10 dage, festivalen varer. Efterspørgslen er ekstremt uforudsigelig og svinger efter vejr, musikprogram og kundernes luner....

Energetic solar particles

International Nuclear Information System (INIS)

Biswas, M.

1975-01-01

In this review, some of the important aspects of energetic solar particles and their relation to solar physics are discussed. The major aspects of solar cosmic ray studies currently under investigation are identified and attention is focussed on the problems of the physical processes in the sun which may be responsible for these phenomena. The studies of the composition and energy spectra of solar cosmic ray nuclei are related to the basic problem of particle acceleration process in sun and to the composition of elements in solar atmosphere. The composition of higher energy (>20 MeV/amu) multiply charged nuclei of He, C, N, O, Ne, Mg, Si and Fe give information on the abundance of elements in the solar atmosphere. At lower energies (approximately 1-10 MeV/amu), the abundances of these elements show enhancements relative to solar abundances and these enhancements are believed to be due to particle acceleration mechanisms operative in the sun which are not fully understood at present. Studies of the relative abundances of H 2 , H 3 and He 3 isotopes and Li, Be, B nuclei in the solar cosmic rays can also be studied. The question of the relationship of the accelerated particles in the sun to the optical flare phenomena is discussed. Further studies of different aspects of these phenomena may give important clues to a wide ranging phenomena in the active sun. The observational methods employed for these studies are mentioned. (A.K.)

Solar atmospheric neutrinos and the sensitivity floor for solar dark matter annihilation searches

Energy Technology Data Exchange (ETDEWEB)

Argüelles, C.A. [Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge MA (United States); De Wasseige, G. [Vrije Universiteit Brussel, Pleinlaan 2, 1050 Elsene, Brussels (Belgium); Fedynitch, A. [Karlsruhe Institute of Technology, 76021 Karlsruhe (Germany); Jones, B.J.P., E-mail: caad@mit.edu, E-mail: gdewasse@vub.ac.be, E-mail: anatoli.fedynitch@desy.de, E-mail: ben.jones@uta.edu [University of Texas at Arlington, 108 Science Hall, 502 Yates St, Arlington TX (United States)

2017-07-01

Cosmic rays interacting in the solar atmosphere produce showers that result in a flux of high-energy neutrinos from the Sun. These form an irreducible background to indirect solar WIMP self-annihilation searches, which look for heavy dark matter particles annihilating into final states containing neutrinos in the Solar core. This background will eventually create a sensitivity floor for indirect WIMP self-annihilation searches analogous to that imposed by low-energy solar neutrino interactions for direct dark matter detection experiments. We present a new calculation of the flux of solar atmospheric neutrinos with a detailed treatment of systematic uncertainties inherent in solar atmospheric shower evolution, and we use this to derive the sensitivity floor for indirect solar WIMP annihilation analyses. We find that the floor lies less than one order of magnitude beyond the present experimental limits on spin-dependent WIMP-proton cross sections for some mass points, and that the high-energy solar atmospheric neutrino flux may be observable with running and future neutrino telescopes.

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

Energy Technology Data Exchange (ETDEWEB)

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

2012-12-01

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

Virginia Solar Pathways Project: Economic Study of Utility-Administered Solar Programs: Soft Costs, Community Solar, and Tax Normalization Considerations

Energy Technology Data Exchange (ETDEWEB)

Reiter, Emerson [National Renewable Energy Lab. (NREL), Golden, CO (United States); Lowder, Travis [National Renewable Energy Lab. (NREL), Golden, CO (United States); Mathur, Shivani [National Renewable Energy Lab. (NREL), Golden, CO (United States); Mercer, Megan [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-06-23

This report presents economic considerations for solar development in support of the Virginia Solar Pathways Project (VSPP), an effort funded by the U.S. Department of Energy (DOE) SunShot Initiative that seeks to develop a collaborative utility-administered solar strategy for the Commonwealth of Virginia. The results presented are intended to be considered alongside the results of other studies conducted under the VSPP that evaluate the impacts of solar energy on the electric distribution, transmission, and generation systems in Virginia.

National Community Solar Platform

Energy Technology Data Exchange (ETDEWEB)

Rupert, Bart [Clean Energy Collective, Louisville, CO (United States)

2016-06-30

This project was created to provide a National Community Solar Platform (NCSP) portal known as Community Solar Hub, that is available to any entity or individual who wants to develop community solar. This has been done by providing a comprehensive portal to make CEC’s solutions, and other proven community solar solutions, externally available for everyone to access – making the process easy through proven platforms to protect subscribers, developers and utilities. The successful completion of this project provides these tools via a web platform and integration APIs, a wide spectrum of community solar projects included in the platform, multiple groups of customers (utilities, EPCs, and advocates) using the platform to develop community solar, and open access to anyone interested in community solar. CEC’s Incubator project includes web-based informational resources, integrated systems for project information and billing systems, and engagement with customers and users by community solar experts. The combined effort externalizes much of Clean Energy Collective’s industry-leading expertise, allowing third parties to develop community solar without duplicating expensive start-up efforts. The availability of this platform creates community solar projects that are cheaper to build and cheaper to participate in, furthering the goals of DOE’s SunShot Initiative. Final SF 425 Final SF 428 Final DOE F 2050.11 Final Report Narrative

Bright Idea: Solar Energy Primer.

Science.gov (United States)

Missouri State Dept. of Natural Resources, Jefferson City.

This booklet is intended to address questions most frequently asked about solar energy. It provides basic information and a starting point for prospective solar energy users. Information includes discussion of solar space heating, solar water heating, and solar greenhouses. (Author/RE)

Solar engineering of thermal processes

CERN Document Server

Duffie, John A

2013-01-01

The updated fourth edition of the ""bible"" of solar energy theory and applications Over several editions, Solar Engineering of Thermal Processes has become a classic solar engineering text and reference. This revised Fourth Edition offers current coverage of solar energy theory, systems design, and applications in different market sectors along with an emphasis on solar system design and analysis using simulations to help readers translate theory into practice. An important resource for students of solar engineering, solar energy, and alternative energy as well

Advanced solar energy conversion. [solar pumped gas lasers

Science.gov (United States)

Lee, J. H.

1981-01-01

An atomic iodine laser, a candidate for the direct solar pumped lasers, was successfully excited with a 4 kW beam from a xenon arc solar simulator, thus proving the feasibility of the concept. The experimental set up and the laser output as functions of operating conditions are presented. The preliminary results of the iodine laser amplifier pumped with the HCP array to which a Q switch for giant pulse production was coupled are included. Two invention disclosures - a laser driven magnetohydrodynamic generator for conversion of laser energy to electricity and solar pumped gas lasers - are also included.

Solar saddle bags. Solar-Fahrradpacktaschen

Energy Technology Data Exchange (ETDEWEB)

Willems, M

1991-09-12

The invention consists of the arrangement of solar cells on the upper side of saddle bags of every design (handle bar pocket, bicycle saddle bag etc.) which charge the accumulators in the pack pocket. One can drive the alternator of the bicycle, a transistor radio, a cassette tape recorder, or similar, with the power from the accumulators. The lamp and the taillight of the bicycle can still be used. The solar cells can be attached firmly to the pack pocket. However, they can also be assembled detachably, e.g. by push-buttons or zip-fasteners.

Solar energy storage

CERN Document Server

Sorensen, Bent

2015-01-01

While solar is the fastest-growing energy source in the world, key concerns around solar power's inherent variability threaten to de-rail that scale-up . Currently, integration of intermittent solar resources into the grid creates added complication to load management, leading some utilities to reject it altogether, while other operators may penalize the producers via rate increases or force solar developers to include storage devices on-site to smooth out power delivery at the point of production. However these efforts at mitigation unfold, it is increasingly clear to parties on all sides th

Solar neutrino experiments

International Nuclear Information System (INIS)

Hampel, W.

1996-01-01

The present status of experimental solar neutrino research is reviewed. Updated results from the Homestake, Kamiokande, GALLEX and SAGE detectors all show a deficit when compared to recent standard solar model calculations. Two of these detectors, GALLEX and SAGE, have recently been checked with artificial 51 Cr neutrino sources. It is shown that astrophysical scenarios to solve the solar neutrino problems are not favoured by the data. There is hope that the results of forthcoming solar neutrino experiments can provide the answers to the open questions. (author) 6 figs., 3 tabs., 36 refs

Solar neutrino experiments

Energy Technology Data Exchange (ETDEWEB)

Hampel, W [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany)

1996-11-01

The present status of experimental solar neutrino research is reviewed. Updated results from the Homestake, Kamiokande, GALLEX and SAGE detectors all show a deficit when compared to recent standard solar model calculations. Two of these detectors, GALLEX and SAGE, have recently been checked with artificial {sup 51}Cr neutrino sources. It is shown that astrophysical scenarios to solve the solar neutrino problems are not favoured by the data. There is hope that the results of forthcoming solar neutrino experiments can provide the answers to the open questions. (author) 6 figs., 3 tabs., 36 refs.

Passive solar technology

Energy Technology Data Exchange (ETDEWEB)

Watson, D

1981-04-01

The present status of passive solar technology is summarized, including passive solar heating, cooling and daylighting. The key roles of the passive solar system designer and of innovation in the building industry are described. After definitions of passive design and a summary of passive design principles are given, performance and costs of passive solar technology are discussed. Passive energy design concepts or methods are then considered in the context of the overall process by which building decisions are made to achieve the integration of new techniques into conventional design. (LEW).

Solar Energy Basics | NREL

Science.gov (United States)

Solar Energy Basics Solar Energy Basics Solar is the Latin word for sun-a powerful source of energy that can be used to heat, cool, and light our homes and businesses. That's because more energy from the technologies convert sunlight to usable energy for buildings. The most commonly used solar technologies for

Solar Deployment System (SolarDS) Model: Documentation and Sample Results

Energy Technology Data Exchange (ETDEWEB)

Denholm, P.; Drury, E.; Margolis, R.

2009-09-01

The Solar Deployment System (SolarDS) model is a bottom-up, market penetration model that simulates the potential adoption of photovoltaics (PV) on residential and commercial rooftops in the continental United States through 2030. NREL developed SolarDS to examine the market competitiveness of PV based on regional solar resources, capital costs, electricity prices, utility rate structures, and federal and local incentives. The model uses the projected financial performance of PV systems to simulate PV adoption for building types and regions then aggregates adoption to state and national levels. The main components of SolarDS include a PV performance simulator, a PV annual revenue calculator, a PV financial performance calculator, a PV market share calculator, and a regional aggregator. The model simulates a variety of installed PV capacity for a range of user-specified input parameters. PV market penetration levels from 15 to 193 GW by 2030 were simulated in preliminary model runs. SolarDS results are primarily driven by three model assumptions: (1) future PV cost reductions, (2) the maximum PV market share assumed for systems with given financial performance, and (3) PV financing parameters and policy-driven assumptions, such as the possible future cost of carbon emissions.

The turbulent cascade and proton heating in the solar wind during solar minimum

International Nuclear Information System (INIS)

Coburn, Jesse T.; Smith, Charles W.; Vasquez, Bernard J.; Stawarz, Joshua E.; Forman, Miriam A.

2013-01-01

Solar wind measurements at 1 AU during the recent solar minimum and previous studies of solar maximum provide an opportunity to study the effects of the changing solar cycle on in situ heating. Our interest is to compare the levels of activity associated with turbulence and proton heating. Large-scale shears in the flow caused by transient activity are a source that drives turbulence that heats the solar wind, but as the solar cycle progresses the dynamics that drive the turbulence and heat the medium are likely to change. The application of third-moment theory to Advanced Composition Explorer (ACE) data gives the turbulent energy cascade rate which is not seen to vary with the solar cycle. Likewise, an empirical heating rate shows no significan changes in proton heating over the cycle.

Solar energy conversion systems

CERN Document Server

Brownson, Jeffrey R S

2013-01-01

Solar energy conversion requires a different mind-set from traditional energy engineering in order to assess distribution, scales of use, systems design, predictive economic models for fluctuating solar resources, and planning to address transient cycles and social adoption. Solar Energy Conversion Systems examines solar energy conversion as an integrative design process, applying systems thinking methods to a solid knowledge base for creators of solar energy systems. This approach permits different levels of access for the emerging broad audience of scientists, engineers, architects, planners

Solar: California, not dreaming

Energy Technology Data Exchange (ETDEWEB)

Jones, J.

2006-03-15

The California Solar Initiative (CSI) was approved by the California Public Utilities Commission (PUC) in January 2006. The CSI is the largest solar programme of this kind ever in the USA and provides for $3.2 billion in incentives for solar projects between 2007 and 2017. The PUC will oversee a $2.5 billion programme to provide funding for solar installations on commercial and existing residential buildings, while the California Energy Commission (CEC) will manage a separate $350 million fund targeted at new residential building. Existing solar programmes operated by the PUC and CEC will be consolidated into the CSI. The CEC programme will use already allocated funding, but the PUC programme will be funded through revenues collected from customers of the main gas and electric utilities in California. Funds will be distributed via rebates to householders or companies that install solar. As well as solar photovoltaics (PV), rebates will also go to solar thermal power (concentrating solar power) and solar heating and cooling. CSI funding can be used in combination with existing federal tax credits. The aim is a gradual increase from installation of 40 MW of PV in 2005 to 100 MW by 2009. The CSI is also expected to create favourable market conditions for PV manufacturers in California and to encourage investment in production of solar-grade silicon in or near California. Objections from the International Brotherhood of Electrical Workers (IBEW) appear to have been overcome but a number of other potential snags remain. CSI is expected to be replicated in other US states.

Job creation potential of solar

International Nuclear Information System (INIS)

McMonagle, R.

2005-01-01

This document defines the size of the job market within Canada's solar industry and presents a preliminary forecast of the employment opportunities through to 2025. The issue of job potential within Canada's solar technologies is complicated by the wide range of different fields and technologies within the solar industry. The largest energy generator of the solar technologies is passive solar, but the jobs in this sector are generally in the construction trades and window manufacturers. The Canadian Solar Industries Association estimates that there are about 360 to 500 firms in Canada with the primary business of solar technologies, employing between 900 to 1,200 employees. However, most solar manufacturing jobs in Canada are for products exports as demonstrated by the 5 main solar manufacturers in Canada who estimate that 50 to 95 per cent of their products are exported. The main reason for their high export ratio is the lack of a Canadian market for their products. The 3 categories of job classifications within the solar industry include manufacturing, installation, and operations and maintenance. The indirect jobs include photovoltaic system hardware, solar hot water heating, solar air ventilation, and glass/metal framing. 17 refs., 3 tabs., 2 figs

Medium level of direct solar radiation and energetic potential of solar concentrator in Minas Gerais State, Brazil; Niveis medios de radiacao solar direta e potencial energetico dos concentradores solares em Minas Gerais

Energy Technology Data Exchange (ETDEWEB)

NONE

1991-07-01

Basic concepts of solar energy, technical description of solar concentrators, its orientation and methodology of direct solar radiation measurement are discussed. An comparison of different solar radiation measurements methods, its methodology and its calculation steps are reported. Calculus and tables of the electric and thermal energy generation potential, through solar concentrators, on the state of Minas Gerais are also presented. 18 figs., 90 tabs., 12 refs.

Solar campaign 'Solar - na klar.' (solar - of course). Final report; Solarkampagne 'Solar - na klar.'. Abschlussbericht

Energy Technology Data Exchange (ETDEWEB)

Gege, M.; Kleinsteuber, A.; Krabbe, P.; Kroeger, P.; Maschke, K.; Niedert, S.; Schindelmann, F.; Thunert, A.; Weinberg, H.

2002-03-18

The German market for technically matured solar-thermal systems for generating hot water is growing by 20 per cent per year, with some deviations due to incentive policies. This growth can be and is planned to be increased systematically, with following goals: A practical contribution to the Federal Government's efforts to achieve the goals regarding the protection of climate; creating future-oriented jobs; supporting ecologically sustainable ways of life and models of consumption by convincing the consumers and other target groups of the fact that it makes sense already today to start utilizing solar energy and to invest also on private basis. These targets are expected to be set up with the help of a three-year mass campaign (1999 until 2001), i.e. the campaign called ''Solar - na klar.'' (solar - of course). [German] Der deutsche Markt fuer die technisch ausgereiften solarthermischen Anlagen zur Warmwassererzeugung waechst mit ca. 20% p.a., mit foerderpolitisch bedingten Schwankungen. Dieses Wachstum kann und soll systematisch gesteigert werden, mit folgenden Zielsetzungen: Praktischer Beitrag zur Erreichung der Klimaschutzziele der Bundesregierung; Schaffung zukunftsorientierter Arbeitsplaetze; Befoerderung oekologisch nachhaltiger Lebensstile und Konsummuster durch die Ueberzeugung der Verbraucher und weiterer Zielgruppen, dass es heute bereits sinnvoll ist, in die Nutzung der Solarenergie konkret einzusteigen und auch privat zu investieren. Diese Ziele sollen mithilfe einer auf drei Jahre angelegten Breitenkampagne (1999 bis 2001), d.h. der Kampagne 'Solar - na klar.' erfolgen. (orig.)

Solar-wind predictions for the Parker Solar Probe orbit. Near-Sun extrapolations derived from an empirical solar-wind model based on Helios and OMNI observations

Science.gov (United States)

Venzmer, M. S.; Bothmer, V.

2018-03-01

Context. The Parker Solar Probe (PSP; formerly Solar Probe Plus) mission will be humanitys first in situ exploration of the solar corona with closest perihelia at 9.86 solar radii (R⊙) distance to the Sun. It will help answer hitherto unresolved questions on the heating of the solar corona and the source and acceleration of the solar wind and solar energetic particles. The scope of this study is to model the solar-wind environment for PSPs unprecedented distances in its prime mission phase during the years 2018 to 2025. The study is performed within the Coronagraphic German And US SolarProbePlus Survey (CGAUSS) which is the German contribution to the PSP mission as part of the Wide-field Imager for Solar PRobe. Aim. We present an empirical solar-wind model for the inner heliosphere which is derived from OMNI and Helios data. The German-US space probes Helios 1 and Helios 2 flew in the 1970s and observed solar wind in the ecliptic within heliocentric distances of 0.29 au to 0.98 au. The OMNI database consists of multi-spacecraft intercalibrated in situ data obtained near 1 au over more than five solar cycles. The international sunspot number (SSN) and its predictions are used to derive dependencies of the major solar-wind parameters on solar activity and to forecast their properties for the PSP mission. Methods: The frequency distributions for the solar-wind key parameters, magnetic field strength, proton velocity, density, and temperature, are represented by lognormal functions. In addition, we consider the velocity distributions bi-componental shape, consisting of a slower and a faster part. Functional relations to solar activity are compiled with use of the OMNI data by correlating and fitting the frequency distributions with the SSN. Further, based on the combined data set from both Helios probes, the parameters frequency distributions are fitted with respect to solar distance to obtain power law dependencies. Thus an empirical solar-wind model for the inner

Solar combi systems

DEFF Research Database (Denmark)

Andersen, Elsa

2007-01-01

The focus in the present Ph.D. thesis is on the active use of solar energy for domestic hot water and space heating in so-called solar combi systems. Most efforts have been put into detailed investigations on the design of solar combi systems and on devices used for building up thermal...... the thermal behaviour of different components, and the theoretical investigations are used to study the influence of the thermal behaviour on the yearly thermal performance of solar combi systems. The experimental investigations imply detailed temperature measurements and flow visualization with the Particle...... Image Velocimetry measurement method. The theoretical investigations are based on the transient simulation program TrnSys and Computational Fluid Dynamics. The Ph.D. thesis demonstrates the influence on the thermal performance of solar combi systems of a number of different parameters...

Solar energy: Technology and applications

Science.gov (United States)

Williams, J. R.

1974-01-01

It is pointed out that in 1970 the total energy consumed in the U.S. was equal to the energy of sunlight received by only 0.15% of the land area of the continental U.S. The utilization of solar energy might, therefore, provide an approach for solving the energy crisis produced by the consumption of irreplaceable fossil fuels at a steadily increasing rate. Questions regarding the availability of solar energy are discussed along with the design of solar energy collectors and various approaches for heating houses and buildings by utilizing solar radiation. Other subjects considered are related to the heating of water partly or entirely with solar energy, the design of air conditioning systems based on the use of solar energy, electric power generation by a solar thermal and a photovoltaic approach, solar total energy systems, industrial and agricultural applications of solar energy, solar stills, the utilization of ocean thermal power, power systems based on the use of wind, and solar-energy power systems making use of geosynchronous power plants.

A hybrid solar and chemical looping combustion system for solar thermal energy storage

International Nuclear Information System (INIS)

Jafarian, Mehdi; Arjomandi, Maziar; Nathan, Graham J.

2013-01-01

Highlights: ► A novel solar–CLC hybrid system is proposed which integrates a CLC with solar thermal energy. ► The oxygen carrier particles are used as storage medium for thermal energy storage. ► A solar cavity reactor is proposed for fuel reactor. ► The absorbed solar energy is stored in the particles to produce a base heat load. -- Abstract: A novel hybrid of a solar thermal energy and a chemical looping combustion (CLC) system is proposed here, which employs the oxygen carrier particles in a CLC system to provide diurnal thermal energy storage for concentrated solar thermal energy. In taking advantage of the chemical and sensible energy storage systems that are an inherent part of a CLC system, this hybrid offers potential to achieve cost effective, base load power generation for solar energy. In the proposed system, three reservoirs have been added to a conventional CLC system to allow storage of the oxygen carrier particles, while a cavity solar receiver has been chosen for the fuel reactor. The performance of the system is evaluated using ASPEN PLUS software, with the model being validated using independent simulation result reported previously. Operating temperature, solar efficiency, solar fraction, exergy efficiency and the fraction of the solar thermal energy stored for a based load power generation application are reported.

Water decontamination by solar photocatalysis. Descontaminacion de aguas residuales mediante fotocatalisis solar

Energy Technology Data Exchange (ETDEWEB)

Blanco Galvez, J; Malato Rodriguez, S

1993-01-01

A solar photocatalytic system is being developed at the Plataforma Solar de Almeria to destroy organic contaminants in water. Test with common water contaminants were conducted at the Solar Detoxification Loop with real sunlight and large quantities of water flowing through glass tubes were the solar UV light is concentrated. Experiments at this scale provide verification of laboratory studies and allow the design and operation of real preindustrial detoxification systems. (Author)

Solar energy in Israel

International Nuclear Information System (INIS)

Zvirin, Y.; Zamkow, S.

1993-01-01

The state of Israel has been a pioneer in the solar energy development and utilization since it was founded. In the 50's solar domestic home heaters became commercially available. At the same time research work has been started in different areas of solar energy, which led to more advanced solar systems for additional applications. The presentation includes some details of commercial utilization of solar energy and a brief description of the main Research and Development projects in industry, universities and research institutes. (authors)

Sun and solar flares

Energy Technology Data Exchange (ETDEWEB)

McKenna-Lawlor, S. (Saint Patrick' s Coll., Maynooth (Ireland))

1982-07-01

The subject is discussed under the headings: the sun's core (thermonuclear reactions, energy transfer from core through radiation zone, convection zone, photosphere, chromosphere and corona); the photosphere (convection, granulation, sunspots, magnetic fields, solar cycle, rotation of the sun); solar variability and paleoclimatic records (correlation of low solar activity with increased /sup 14/C production in atmosphere); the chromosphere and corona (turbulence, temperature, coronal streamers, energy transfer); solar flares (cosmic rays, aurorae, spectra, velocity of flares, prominences, mechanisms of flares); the solar wind.

Four-cell solar tracker

Science.gov (United States)

Berdahl, C. M.

1981-01-01

Forty cm Sun tracker, consisting of optical telescope and four solar cells, stays pointed at Sun throughout day for maximum energy collection. Each solar cell generates voltage proportional to part of solar image it receives; voltages drive servomotors that keep image centered. Mirrored portion of cylinder extends acquisition angle of device by reflecting Sun image back onto solar cells.

Pyramid solar micro-grid

Science.gov (United States)

Huang, Bin-Juine; Hsu, Po-Chien; Wang, Yi-Hung; Tang, Tzu-Chiao; Wang, Jia-Wei; Dong, Xin-Hong; Hsu, Hsin-Yi; Li, Kang; Lee, Kung-Yen

2018-03-01

A novel pyramid solar micro-grid is proposed in the present study. All the members within the micro-grid can mutually share excess solar PV power each other through a binary-connection hierarchy. The test results of a 2+2 pyramid solar micro-grid consisting of 4 individual solar PV systems for self-consumption are reported.

Solar Installation Labor Market Analysis

Energy Technology Data Exchange (ETDEWEB)

Friedman, B.; Jordan, P.; Carrese, J.

2011-12-01

The potential economic benefits of the growing renewable energy sector have led to increased federal, state, and local investments in solar industries, including federal grants for expanded workforce training for U.S. solar installers. However, there remain gaps in the data required to understand the size and composition of the workforce needed to meet the demand for solar power. Through primary research on the U.S. solar installation employer base, this report seeks to address that gap, improving policymakers and other solar stakeholders understanding of both the evolving needs of these employers and the economic opportunity associated with solar market development. Included are labor market data covering current U.S. employment, expected industry growth, and employer skill preferences for solar installation-related occupations. This study offers an in-depth look at the solar installation sectors. A study published by the Solar Foundation in October 2011 provides a census of labor data across the entire solar value chain.

Solar chulha

Energy Technology Data Exchange (ETDEWEB)

Jadhao, P. H. [Department of Physics J.D. Institute of Engg. & Tech. Yavatmal (India); Patrikar, S. R. [Department of Physics VNIT, Nagpur (India)

2016-05-06

The main goal of the proposed system is to transfer energy from sun to the cooking load that is located in the kitchen. The energy is first collected by the solar collector lens system and two curve bars of same radius of curvature are mounted parallel and adjacent to each other at different height the solar collector is clamed on this two bars such that solar collector is exactly perpendicular to sunlight. The topology includes an additional feature which is window in the wall through which the beam is collimated is directed in the of kitchen. The solar energy that is collected is directed by the mirror system into the kitchen, where it is redirected to cooking platform located in the kitchen. The special feature in this system full Indian meal can be made since cooking platform is indoors.

Determination of variations of the solar radius from solar eclipse observations

Science.gov (United States)

Sofia, S.; Dunham, D. W.; Fiala, A. D.

1980-01-01

This paper describes the method to determine the solar radius and its variations from observations made during total solar eclipses. In particular, the procedure to correct the spherical moon predictions for the effects of lunar mountains and valleys on the width and location of the path of totality is addressed in detail. The errors affecting this technique are addressed, a summary of the results of its application to three solar eclipses are presented, and the implications of the results on the constancy of the solar constant are described.

Integrated solar water-heater and solar water cooler performance during winter time

International Nuclear Information System (INIS)

Shaikh, N.U.; Siddiqui, M.A

2012-01-01

Solar powered water heater and water cooler is an important contribution for the reduction of fossil fuel consumptions and harmful emissions to the environment. This study aims to harness the available solar potential of Pakistan and provide an option fulfilling the domestic hot and cold water demands during winter and summer seasons respectively. The system was designed for the tap-water temperature of 65 degree C (149 degree F) and the chilled drinking-water temperature of 14 degree C (57 degree F) that are the recommended temperatures by World Health Organization (WHO). The solar water heater serves one of the facilities of the Department of Mechanical Engineering at NED University of Engineering and Technology whereas, the solar water cooler will provide drinking water to approximately 50 people including both faculty and students. A pair of single glazed flat plate solar collector was installed to convert solar radiations to heat. Hot water storage and supply system was carefully designed and fabricated to obtain the designed tap-water temperature. Vapour-absorption refrigeration system was designed to chill drinking water. Intensity of solar radiations falling on the solar collector, water temperatures at the inlet and outlet of the solar collectors and the tap water temperature were measured and analyzed at different hours of the day and at different days of the month. The results show that the installed solar collector system has potential to feed hot water of temperatures ranging from 65 degree C (149 degree F) to 70 Degree C (158 degree F), that is the required hot water temperature to operate a vapour absorption chilled water production system. (author)

1986 Flood Control and Navigation Maps of the Mississippi River

Science.gov (United States)

1987-01-01

Leatherman Point, La. 42 294.3 Lower Limits, Ark. 22 605.0 21 622.0 Ledbetter Ldg., Miss. 20 Upper Limits, Ark. 19 655.3 S7 10 5 Lee Towhead. Mo...8217 """■"■■ CHARTS 5 CORPS OF ENGINEERS MIDDLE MISSISSIPPI RIVER mmmmmammm LEE ISLAND ^ SIARUNuC ÜANSNFR FLEETING AREA y^— AMES TOWHEAD . Morrison...ROCK LANDING Cambria Hollow ESlABLISHlJfeWWl White Sand Creek STRINGTOWN - FORT CHARTRES , 3^’ AND IVY LANDING FOfft CHARTRES BEND LT ^ Doymark

Solar collectors

Energy Technology Data Exchange (ETDEWEB)

Hullmann, H; Schmidt, B [Technische Univ. Hannover (Germany, F.R.). Inst. fuer Industrialisierung des Bauens

1976-01-01

The utilisation possibilities of solar energy for the energy supplying of buildings are becoming increasingly more significant. Solar research at the moment aims predominantly with a high level of efficiency and therefore making accessible a significant range of applications for solar technology. Parallel to this are attempts to effect the saving of energy, be it in the demand for energy-saving constructions or in the increasing development and application of rational energy utilisation by technologists. The most important point of these activities at the moment, is still technological methods.

Solar Renewable Energy. Teaching Unit.

Science.gov (United States)

Buchanan, Marion; And Others

This unit develops the concept of solar energy as a renewable resource. It includes: (1) an introductory section (developing understandings of photosynthesis and impact of solar energy); (2) information on solar energy use (including applications and geographic limitations of solar energy use); and (3) future considerations of solar energy…

Solar tracking system

Science.gov (United States)

Okandan, Murat; Nielson, Gregory N.

2016-07-12

Solar tracking systems, as well as methods of using such solar tracking systems, are disclosed. More particularly, embodiments of the solar tracking systems include lateral supports horizontally positioned between uprights to support photovoltaic modules. The lateral supports may be raised and lowered along the uprights or translated to cause the photovoltaic modules to track the moving sun.

EFFICIENCY AND LIFETIME OF SOLAR COLLECTORS FOR SOLAR HEATING PLANTS

DEFF Research Database (Denmark)

The 12.5 m² flat plate solar collector HT, today marketed by Arcon Solvarme A/S, has been used in solar heating plants in Scandinavia since 1983. The collector is designed to operate in a temperature interval between 40°C and 90°C. The efficiency of the collector has been strongly improved since...... it was introduced on the market. The paper will present the increase of the efficiency of the collector due to technical improvements since 1983. Further, measurements from the spring of 2009 of the efficiency of two HT collectors, which have been in operation in the solar heating plant Ottrupgaard, Skørping......, Denmark since 1994 with a constant high flow rate and in the solar heating plant Marstal, Denmark since 1996 with a variable flow rate, will be presented. The efficiencies will be compared to the efficiencies of the collectors when they were first installed in the solar heating plants. The measurements...

EFFICIENCY AND LIFETIME OF SOLAR COLLECTORS FOR SOLAR HEATING PLANTS

DEFF Research Database (Denmark)

Fan, Jianhua; Chen, Ziqian; Furbo, Simon

2009-01-01

The 12.5 m² flat plate solar collector HT, today marketed by Arcon Solvarme A/S, has been used in solar heating plants in Scandinavia since 1983. The collector is designed to operate in a temperature interval between 40°C and 90°C. The efficiency of the collector has been strongly improved since...... it was introduced on the market. The paper will present the increase of the efficiency of the collector due to technical improvements since 1983. Further, measurements from the spring of 2009 of the efficiency of two HT collectors, which have been in operation in the solar heating plant Ottrupgaard, Skørping......, Denmark since 1994 with a constant high flow rate and in the solar heating plant Marstal, Denmark since 1996 with a variable flow rate, will be presented. The efficiencies will be compared to the efficiencies of the collectors when they were first installed in the solar heating plants. The measurements...

Solar system astrophysics planetary atmospheres and the outer solar system

CERN Document Server

Milone, Eugene F

2014-01-01

The second edition of Solar System Astrophysics: Planetary Atmospheres and the Outer Solar System provides a timely update of our knowledge of planetary atmospheres and the bodies of the outer solar system and their analogs in other planetary systems. This volume begins with an expanded treatment of the physics, chemistry, and meteorology of the atmospheres of the Earth, Venus, and Mars, moving on to their magnetospheres and then to a full discussion of the gas and ice giants and their properties. From here, attention switches to the small bodies of the solar system, beginning with the natural satellites. Then comets, meteors, meteorites, and asteroids are discussed in order, and the volume concludes with the origin and evolution of our solar system. Finally, a fully revised section on extrasolar planetary systems puts the development of our system in a wider and increasingly well understood galactic context. All of the material is presented within a framework of historical importance. This book and its sist...

Solar radiation absorbing material

Science.gov (United States)

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.

Solar 92: The 1992 American Solar Energy Society annual conference

International Nuclear Information System (INIS)

Burley, S.; Arden, M.E.

1992-01-01

The purpose of this symposium is to document the lessons learned from federal and state policies and programs in the late 1970's and 1980's aimed at promoting consumer use of solar energy. During this period the primary emphasis was on solar thermal technologies and passive solar design that could be used at the residential level, though there was also some information on stand-alone photovoltaic systems as well

Construction of a century solar chromosphere data set for solar activity related research

Science.gov (United States)

Lin, Ganghua; Wang, Xiao Fan; Yang, Xiao; Liu, Suo; Zhang, Mei; Wang, Haimin; Liu, Chang; Xu, Yan; Tlatov, Andrey; Demidov, Mihail; Borovik, Aleksandr; Golovko, Aleksey

2017-06-01

This article introduces our ongoing project "Construction of a Century Solar Chromosphere Data Set for Solar Activity Related Research". Solar activities are the major sources of space weather that affects human lives. Some of the serious space weather consequences, for instance, include interruption of space communication and navigation, compromising the safety of astronauts and satellites, and damaging power grids. Therefore, the solar activity research has both scientific and social impacts. The major database is built up from digitized and standardized film data obtained by several observatories around the world and covers a time span of more than 100 years. After careful calibration, we will develop feature extraction and data mining tools and provide them together with the comprehensive database for the astronomical community. Our final goal is to address several physical issues: filament behavior in solar cycles, abnormal behavior of solar cycle 24, large-scale solar eruptions, and sympathetic remote brightenings. Significant signs of progress are expected in data mining algorithms and software development, which will benefit the scientific analysis and eventually advance our understanding of solar cycles.

Construction of a century solar chromosphere data set for solar activity related research

Directory of Open Access Journals (Sweden)

Ganghua Lin

2017-06-01

Full Text Available This article introduces our ongoing project “Construction of a Century Solar Chromosphere Data Set for Solar Activity Related Research”. Solar activities are the major sources of space weather that affects human lives. Some of the serious space weather consequences, for instance, include interruption of space communication and navigation, compromising the safety of astronauts and satellites, and damaging power grids. Therefore, the solar activity research has both scientific and social impacts. The major database is built up from digitized and standardized film data obtained by several observatories around the world and covers a timespan more than 100 years. After careful calibration, we will develop feature extraction and data mining tools and provide them together with the comprehensive database for the astronomical community. Our final goal is to address several physical issues: filament behavior in solar cycles, abnormal behavior of solar cycle 24, large-scale solar eruptions, and sympathetic remote brightenings. Significant progresses are expected in data mining algorithms and software development, which will benefit the scientific analysis and eventually advance our understanding of solar cycles.

Candidate solar cell materials for photovoltaic conversion in a solar power satellite /SPS/

Science.gov (United States)

Glaser, P. E.; Almgren, D. W.

1978-01-01

In recognition of the obstacles to solar-generated baseload power on earth, proposals have been made to locate solar power satellites in geosynchronous earth orbit (GEO), where solar energy would be available 24 hours a day during most of the time of the year. In an SPS, the electricity produced by solar energy conversion will be fed to microwave generators forming part of a planar phase-array transmitting antenna. The antenna is designed to precisely direct a microwave beam of very low intensity to one or more receiving antennas at desired locations on earth. At the receiving antenna, the microwave energy will be safely and efficiently reconverted to electricity and then be transmitted to consumers. An SPS system will include a number of satellites in GEO. Attention is given to the photovoltaic option for solar energy conversion in GEO, solar cell requirements, the availability of materials, the implication of large production volumes, requirements for high-volume manufacture of solar cell arrays, and the effects of concentration ratio on solar cell array area.

Recent Overview of Solar Photocatalysis and Solar Photo-Fenton Processes for Wastewater Treatment

Directory of Open Access Journals (Sweden)

A. G. Gutierrez-Mata

2017-01-01

Full Text Available This literature research, although not exhaustive, gives perspective to solar-driven photocatalysis, such as solar photo-Fenton and TiO2 solar photocatalysis, reported in the literature for the degradation of aqueous organic pollutants. Parameters that influence the degradation and mineralization of organics like catalyst preparation, type and load of catalyst, catalyst phase, pH, applied potential, and type of organic pollutant are addressed. Such parameters may also affect the photoactivity of the catalysts used in the studied solar processes. Solar irradiation is a renewable, abundant, and pollution-free energy source for low-cost commercial applications. Therefore, these solar processes represent an environmentally friendly alternative mainly because the use of electricity can be decreased/avoided.

Solar origins of solar wind properties during the cycle 23 solar minimum and rising phase of cycle 24

Science.gov (United States)

Luhmann, Janet G.; Petrie, Gordon; Riley, Pete

2012-01-01

The solar wind was originally envisioned using a simple dipolar corona/polar coronal hole sources picture, but modern observations and models, together with the recent unusual solar cycle minimum, have demonstrated the limitations of this picture. The solar surface fields in both polar and low-to-mid-latitude active region zones routinely produce coronal magnetic fields and related solar wind sources much more complex than a dipole. This makes low-to-mid latitude coronal holes and their associated streamer boundaries major contributors to what is observed in the ecliptic and affects the Earth. In this paper we use magnetogram-based coronal field models to describe the conditions that prevailed in the corona from the decline of cycle 23 into the rising phase of cycle 24. The results emphasize the need for adopting new views of what is ‘typical’ solar wind, even when the Sun is relatively inactive. PMID:25685422

Comparative evaluation of solar, fission, fusion, and fossil energy resources. Part 1: Solar energy

Science.gov (United States)

Williams, J. R.

1974-01-01

The utilization of solar energy to meet the energy needs of the U.S. is discussed. Topics discussed include: availability of solar energy, solar energy collectors, heating for houses and buildings, solar water heater, electric power generation, and ocean thermal power.

Solar processing of CO2 and H2O, routes for solar fuels

International Nuclear Information System (INIS)

Flammant, G.; Abanades, St.

2008-01-01

Complete text of publication follows: Concentrated solar energy provides heat in the temperature range 200 C - 3000 C for concentration ratio variation from 10 to 10 000 (three orders of magnitude). Consequently, solar-driven thermochemical processes may be proposed to produce hydrogen from water decomposition and to reduce carbon dioxide. This lecture gives an overview of such processes. High temperature thermochemical cycles for hydrogen production by water splitting are currently studied at PROMES lab, particularly 2-step and 3-step cycles based on the following reaction scheme, MOox → MOred + 1/2 O 2 (high temperature solar step), MOred + H 2 O → MOox + H 2 (low temperature non solar step). Volatile and non-volatile oxide cycles are developed from the chemical and the engineering points of view. A similar reaction scheme may be proposed to reduce carbon dioxide with concentrated solar energy (Fig. 1), it comes, MOox → MOred + 1/2 O 2 (high temperature solar step), MOred + CO 2 → MOox + CO (low temperature non solar step). As a result gas mixtures such as CO 2 /H 2 and CO/H 2 may be produced by solar energy. Such mixtures are the reactants for liquid fuels production (solar fuels)

Effect of solar-terrestrial phenomena on solar cell's efficiency

International Nuclear Information System (INIS)

Zahee, K. B.; Ansari, W.A.; Raza, S.M.M.

2012-01-01

It is assumed that the solar cell efficiency of PV device is closely related to the solar irradiance, consider the solar parameter Global Solar Irradiance (G) and the meteorological parameters like daily data of Earth Skin Temperature (E), Average Temperature (T), Relative Humidity (H) and Dew Frost Point (D), for the coastal city Karachi and a non-coastal city Jacobabad, K and J is used as a subscripts for parameters of Karachi and Jacobabad respectively. All variables used here are dependent on the location (latitude and longitude) of our stations except G. To employ ARIMA modeling, the first eighteen years data is used for modeling and forecast is done for the last five years data. In most cases results show good correlation among monthly actual and monthly forecasted values of all the predictors. Next, multiple linear regression is employed to the data obtained by ARIMA modeling and models for mean monthly observed G values are constructed. For each station, two equations are constructed, the R values are above 93% for each model, showing adequacy of the fit. Our computations show that solar cell efficiency can be increased if better modeling for meteorological predictors governs the process. (author)

Experimental study on comprehensive utilization of solar energy and energy balance in an integrated solar house

International Nuclear Information System (INIS)

Chang, Huawei; Liu, Yuting; Shen, Jinqiu; Xiang, Can; He, Sinian; Wan, Zhongmin; Jiang, Meng; Duan, Chen; Shu, Shuiming

2015-01-01

Highlights: • Active and passive solar house technology is integrated in the solar house. • Solar thermal system and solar photoelectric system are measured and analyzed. • Energy balance and energy consumption are analyzed with valuable experimental data. • “Zero energy consumption” is truly achieved with the solar supply rate of 1.19 in winter. - Abstract: An integrated solar house with numerous advanced envelops is designed and constructed to investigate the comprehensive utilization of solar energy, energy efficiency and energy balance, which combines active solar house technology with passive solar house technology including solar photovoltaic system, solar water heating system, direct-gain door and windows. Solar radiation intensity, performance of the photovoltaic system, water temperature, and indoor and outdoor temperature are measured, results of the experiments indicate that solar glass window on the south wall can maintain the average indoor temperature at 21.4 °C in the case of average outdoor temperature at 11.2 °C without any external heat supply. The output current of the solar photovoltaic system shows the same trend as solar radiation intensity. When the intensity is 619.7 W/m"2, the instantaneous generation power could reach a value of 781.9 W, cumulative capacity throughout the day achieves 4.56 kW h and photovoltaic conversion efficiency 9.8%. When the average intensity throughout a day is 358 W/m"2, the solar water heating system could help to raise the temperature of 450 L water by 30 °C with its heat collecting efficiency being 37.4%. Through the analysis of the overall energy system in the solar house, it can be derived that this solar house could achieve “zero energy consumption” in winter with the solar supply rate at 1.19.

Verification of high-speed solar wind stream forecasts using operational solar wind models

DEFF Research Database (Denmark)

Reiss, Martin A.; Temmer, Manuela; Veronig, Astrid M.

2016-01-01

and the background solar wind conditions. We found that both solar wind models are capable of predicting the large-scale features of the observed solar wind speed (root-mean-square error, RMSE ≈100 km/s) but tend to either overestimate (ESWF) or underestimate (WSA) the number of high-speed solar wind streams (threat......High-speed solar wind streams emanating from coronal holes are frequently impinging on the Earth's magnetosphere causing recurrent, medium-level geomagnetic storm activity. Modeling high-speed solar wind streams is thus an essential element of successful space weather forecasting. Here we evaluate...... high-speed stream forecasts made by the empirical solar wind forecast (ESWF) and the semiempirical Wang-Sheeley-Arge (WSA) model based on the in situ plasma measurements from the Advanced Composition Explorer (ACE) spacecraft for the years 2011 to 2014. While the ESWF makes use of an empirical relation...

Frequency agile solar radiotelescope

Science.gov (United States)

Bastian, Tim S.

2003-02-01

The Frequency Agile Solar Radiotelescope (FASR) is a solar-dedicated, ground based, interferometric array optimized to perform broadband imaging spectroscopy from ~ 0.1-30+ GHz. It will do so with the angular, spectral, and temporal resolution required to exploit radio emission from the Sun as a diagnostic of the wide variety of astrophysical processes that occur there. FASR represents a major advance over existing radioheliographs, and is expected to remain the world's premier solar radio instrument for two decades or more after completion. FASR will be a versatile and powerful instrument, providing unique data to a broad users community. Solar, solar-terrestrial, and space physicists will exploit FASR to attack a broad science program, including problems of fundamental interest: coronal magnetography, solar flares and particle acceleration, drivers of space weather, and the thermal structure and dynamics of the solar atmosphere. A design study and implementation planning are underway. Recent progress is reviewed here.

Understanding Solar Cycle Variability

Energy Technology Data Exchange (ETDEWEB)

Cameron, R. H.; Schüssler, M., E-mail: cameron@mps.mpg.de [Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, D-37077 Göttingen (Germany)

2017-07-10

The level of solar magnetic activity, as exemplified by the number of sunspots and by energetic events in the corona, varies on a wide range of timescales. Most prominent is the 11-year solar cycle, which is significantly modulated on longer timescales. Drawing from dynamo theory, together with the empirical results of past solar activity and similar phenomena for solar-like stars, we show that the variability of the solar cycle can be essentially understood in terms of a weakly nonlinear limit cycle affected by random noise. In contrast to ad hoc “toy models” for the solar cycle, this leads to a generic normal-form model, whose parameters are all constrained by observations. The model reproduces the characteristics of the variable solar activity on timescales between decades and millennia, including the occurrence and statistics of extended periods of very low activity (grand minima). Comparison with results obtained with a Babcock–Leighton-type dynamo model confirm the validity of the normal-mode approach.

Household appliances using solar energy technology

International Nuclear Information System (INIS)

Gul, H.

2000-01-01

Many solar energy technologies are now sufficiently developed to make it possible to use these to replace some of our conventional energy sources, but still need improvement and reduction in cost. It is, therefore, necessary to focus attention on household uses of solar energy. This paper describes the recent developments and current position in respect of several such devices, which include; solar cooker, with curved concentrator, Panel Cooker, Solar Dryer, solar water heater, Solar Still, Solar Water Pump, Solar Water Disinfection, Solar space Heating and greenhouse solar Reflectors, Development and Extension activities on these should be taken up at various levels. (author)

Solar energy in Peru

Energy Technology Data Exchange (ETDEWEB)

Pierson, H.

1981-12-01

The past, present, and future of Peru is discussed in terms of solar energy development and the social, economic, climatic, and technical factors involved. It is pointed out that there are 3 geographical divisions in Peru including: (1) the foggy coastal strip where rain is infrequent, insolation is low and population is high; (2) the mountainous Andes region with high insolation and many populated high mountain valleys; and (3) the rainy, Amazon basin covered with jungle, and sparcely populated with high but inconsistent insolation. Since there is little competition with other forms of energy, solar energy shows promise. Passive solar heating of buildings, particularly in the Andes region, is described, as well as the use of solar water heaters. Prototypes are described and illustrated. Industrial use of solar heated water in the wool industry as well as solar food drying and solar desalination are discussed. High temperature applications (electrical generators and refrigeration) as well as photovoltaic systems are discussed briefly. It is concluded that social and political factors are holding back the development of solar energy but a start (in the form of prototypes and demonstration programs) is being made. (MJJ)

High-power, ultralow-mass solar arrays: FY-77 solar arrays technology readiness assessment report, volume 2

Science.gov (United States)

Costogue, E. N.; Young, L. E.; Brandhorst, H. W., Jr.

1978-01-01

Development efforts are reported in detail for: (1) a lightweight solar array system for solar electric propulsion; (2) a high efficiency thin silicon solar cell; (3) conceptual design of 200 W/kg solar arrays; (4) fluorocarbon encapsulation for silicon solar cell array; and (5) technology assessment of concentrator solar arrays.

Profile in solar

International Nuclear Information System (INIS)

Cohen, S.; Woods, A.

1991-01-01

This article reviews an innovative solar hot water heater and its inventor/entrepreneur. It includes the inventor's strategy for developing and marketing the product and his ideas on the state of the solar industry in general. There is a brief description of the solar water heater which has as prominent features its skylight-like appearance, resistance to freeze damage, simplicity and low cost

Control of Solar Energy Systems

CERN Document Server

Camacho, Eduardo F; Rubio, Francisco R; Martínez, Diego

2012-01-01

Control of Solar Energy Systems details the main solar energy systems, problems involved with their control, and how control systems can help in increasing their efficiency.  After a brief introduction to the fundamental concepts associated with the use of solar energy in both photovoltaic and thermal plants, specific issues related to control of solar systems are embarked upon. Thermal energy systems are then explored in depth, as well as  other solar energy applications such as solar furnaces and solar refrigeration systems. Problems of variable generation profile and of the contribution of many solar plants to the same grid system are considered with the necessary integrated and supervisory control solutions being discussed. The text includes material on: ·         A comparison of basic and advanced control methods for parabolic troughs from PID to nonlinear model-based control; ·         solar towers and solar tracking; ·         heliostat calibration, characterization and off...

The solar probe mission

International Nuclear Information System (INIS)

Feldman, W.C.; Anderson, J.; Bohlin, J.D.; Burlaga, L.F.; Farquhar, R.; Gloeckler, G.; Goldstein, B.E.; Harvey, J.W.; Holzer, T.E.; Jones, W.V.; Kellogg, P.J.; Krimigis, S.M.; Kundu, M.R.; Lazarus, A.J.; Mellott, M.M.; Parker, E.N.; Rosner, R.; Rottman, G.J.; Slavin, J.A.; Suess, S.T.; Tsurutani, B.T.; Woo, R.T.; Zwickl, R.D.

1990-01-01

The Solar Probe will deliver a 133.5 kg science payload into a 4 R s perihelion solar polar orbit (with the first perihelion passage in 2004) to explore in situ one of the last frontiers in the solar system---the solar corona. This mission is both affordable and technologically feasible. Using a payload of 12 (predominantly particles and fields) scientific experiments, it will be possible to answer many long-standing, fundamental problems concerning the structure and dynamics of the outer solar atmosphere, including the acceleration, storage, and transport of energetic particles near the Sun and in the inner ( s ) heliosphere

Large-scale solar heating

Energy Technology Data Exchange (ETDEWEB)

Tolonen, J.; Konttinen, P.; Lund, P. [Helsinki Univ. of Technology, Otaniemi (Finland). Advanced Energy Systems

1998-10-01

Solar heating market is growing in many European countries and annually installed collector area has exceeded one million square meters. There are dozens of collector manufacturers and hundreds of firms making solar heating installations in Europe. One tendency in solar heating is towards larger systems. These can be roof integrated, consisting of some tens or hundreds of square meters of collectors, or they can be larger centralized solar district heating plants consisting of a few thousand square meters of collectors. The increase of size can reduce the specific investments of solar heating systems, because e.g. the costs of some components (controllers, pumps, and pipes), planning and installation can be smaller in larger systems. The solar heat output can also be higher in large systems, because more advanced technique is economically viable

Solar panel cleaning robot

Science.gov (United States)

Nalladhimmu, Pavan Kumar Reddy; Priyadarshini, S.

2018-04-01

As the demand of electricity is increasing, there is need to using the renewable sources to produce the energy at present of power shortage, the use of solar energy could be beneficial to great extent and easy to get the maximum efficiency. There is an urgent in improving the efficiency of solar power generation. Current solar panels setups take a major power loss when unwanted obstructions cover the surface of the panels. To make solar energy more efficiency of solar array systems must be maximized efficiency evaluation of PV panels, that has been discussed with particular attention to the presence of dust on the efficiency of the PV panels have been highlighted. This paper gives the how the solar panel cleaning system works and designing of the cleaning system.

Solar cooking

Science.gov (United States)

Over two billion people face fuel wood shortages, causing tremendous personal and environmental stress. Over 4 million people die prematurely from indoor air pollution. Solar cooking can reduce fuel wood consumption and indoor air pollution. Solar cooking has been practiced and published since th...

Solar neutrinos

International Nuclear Information System (INIS)

Schatzman, E.

1983-01-01

The solar energy is produced by a series of nuclear reactions taking place in the deep interior of the sun. Some of these reactions produce neutrinos which may be detected, the proper detection system being available. The results of the Davis experiment (with 37 Cl) are given, showing a deficiency in the solar neutrino flux. The relevant explanation is either a property of the neutrino or an important change in the physics of the solar models. The prospect of a new experiment (with 71 Ga) is important as it will decide which of the two explanations is correct [fr

Solar thermal barometer

International Nuclear Information System (INIS)

Anon.

2004-01-01

After the bad year of 2002, the european solar thermal market returned to double-digit growth rate in 2003: 22%. Nevertheless, the sector still has not recovered the growth rate it had in the early 2000 and European Commission targets are still far from being reached. This paper presents the thermal solar industry barometer. Data on the evolution of annually installed surfaces in the european union since 1993, the cumulated capacity of thermal collectors installed in the European Union, the estimation of the annual energy production associated to european solar thermal capacities and the main companies of the European Union thermal solar sector are presented and discussed. (A.L.B.)

Harnessing solar heat

CERN Document Server

Norton, Brian

2013-01-01

Systems engineered by man to harness solar heat in a controlled manner now include a diverse range of technologies each serving distinctive needs in particular climate contexts. This text covers the breadth of solar energy technologies for the conversion of solar energy to provide heat, either as the directly-used output or as an intermediary to other uses such as power generation or cooling. It is a wholly updated, extended and revised version of “Solar Energy Thermal Technology” first published in 1992. The text draws on the own author’s research and that of numerous colleagues and

Evaluation methods of solar contribution in solar aided coal-fired power generation system

International Nuclear Information System (INIS)

Zhu, Yong; Zhai, Rongrong; Zhao, Miaomiao; Yang, Yongping; Yan, Qin

2015-01-01

Highlights: • Five methods for evaluating solar contribution are analyzed. • Method based on the second law of thermodynamics and thermal economics is more suitable for SACPGS. • Providing reliable reference for the formulation of feed-in tariff policies in China. - Abstract: Solar aided coal-fired power plants utilize solar thermal energy to couple with coal-fired power plants of various types by adopting characteristics of different thermal needs of plants. In this way, the costly thermal storage system and power generating system will become unnecessary, meanwhile the intermittent and unsteady nature of power generation can be avoided. In addition, large-scale utilization of solar thermal power and energy saving can be achieved. With the ever-deepening analyses of solar aided coal-fired power plants, the contribution evaluating system of solar thermal power is worth further exploration. In this paper, five common evaluation methods of solar contribution are analyzed, and solar aided coal-fired power plants of 1000 MW, 600 MW and 330 MW are studied with these five methods in a comparative manner. Therefore, this study can serve as a theoretical reference for future research of evaluation methods and subsidies for new energy

University of Calgary solar car set for American solar challenge

International Nuclear Information System (INIS)

Anon.

2010-01-01

This article described a solar car designed by a team from the University of Calgary for the 2010 American Solar Challenge, a 1100 mile race that starts in Tulsa, Oklahoma and ends 5 days later in Chicago, Illinois. The Shulich Axiom car is comprised of 2000 solar cells with batteries that can store enough power to drive the car for a 4-hour period. The car has a top speed of 140 km per hour and is totally powered by solar energy. The team has taken the car on a 5-day tour of Alberta, stopping in 7 communities across the province before heading back to Calgary. The team is one of only 2 Canadian teams competing in the challenge this year. 1 fig.

Solar Spicules: Prospects for Breakthroughs in Understanding with Solar-B

Science.gov (United States)

Sterling, A.

Spicules densely populate the lower solar atmosphere; any image or movie of the chromosphere shows a plethora of them or their "cousins," such as mottles or fibrils. Yet despite several decades of effort we still do not know the mechanism that generates them, or how important their contribution is to the material and energy balance of the overall solar atmosphere. Solar-B will provide exciting new chromospheric observations at high time- and spatial-resolution, along with associated quality magnetic field data, that promise to open doors to revolutionary breakthroughs in spicule research. In this presentation we will review the current observational and theoretical status of spicule studies, and discuss prospects for advances in spicule understanding during the Solar-B era.

Understanding non-equilibrium collisional and expansion effects in the solar wind with Parker Solar Probe

Science.gov (United States)

Korreck, K. E.; Klein, K. G.; Maruca, B.; Alterman, B. L.

2017-12-01

The evolution of the solar wind from the corona to the Earth and throughout the heliosphere is a complex interplay between local micro kinetics and large scale expansion effects. These processes in the solar wind need to be separated in order to understand and distinguish the dominant mechanism for heating and acceleration of the solar wind. With the upcoming launch in 2018 of Parker Solar Probe and the launch of Solar Orbiter after, addressing the local and global phenomena will be enabled with in situ measurements. Parker Solar Probe will go closer to the Sun than any previous mission enabling the ability to examine the solar wind at an early expansion age. This work examines the predictions for what will be seen inside of the 0.25 AU (54 solar radii) where Parker Solar Probe will take measurements and lays the groundwork for disentangling the expansion and collisional effects. In addition, methods of thermal plasma data analysis to determine the stability of the plasma in the Parker Solar Probe measurements will be discussed.

High-Fidelity Solar Power Income Modeling for Solar-Electric UAVs: Development and Flight Test Based Verification

OpenAIRE

Oettershagen, Philipp

2017-01-01

Solar power models are a crucial element of solar-powered UAV design and performance analysis. During the conceptual design phase, their accuracy directly relates to the accuracy of the predicted performance metrics and thus the final design characteristics of the solar-powered UAV. Likewise, during the operations phase of a solar-powered UAV accurate solar power income models are required to predict and assess the solar power system performance. However, the existing literature on solar-powe...

Thermal solar energy

International Nuclear Information System (INIS)

Gonzalez, J.C.; Leal C, H.

1998-01-01

Some relative aspects to the development and current state of thermal solar energy are summarized, so much at domestic level as international. To facilitate the criteria understanding as the size of the facilities in thermal solar systems, topics as availability of the solar resource and its interactions with the matter are included. Finally, some perspectives for the development of this energetic alternative are presented

Dye solar cells: a different approach to solar energy

CSIR Research Space (South Africa)

Le Roux, Lukas J

2008-11-01

Full Text Available An attractive and cheaper alternative to siliconbased photovoltaic (PV) cells for the conversion of solar light into electrical energy is to utilise dyeadsorbed, large-band-gap metal oxide materials such as TiO2 to absorb the solar light...

Solar wind ion trends and signatures: STEREO PLASTIC observations approaching solar minimum

Directory of Open Access Journals (Sweden)

A. B. Galvin

2009-10-01

Full Text Available STEREO has now completed the first two years of its mission, moving from close proximity to Earth in 2006/2007 to more than 50 degrees longitudinal separation from Earth in 2009. During this time, several large-scale structures have been observed in situ. Given the prevailing solar minimum conditions, these structures have been predominantly coronal hole-associated solar wind, slow solar wind, their interfaces, and the occasional transient event. In this paper, we extend earlier solar wind composition studies into the current solar minimum using high-resolution (1-h sampling times for the charge state analysis. We examine 2-year trends for iron charge states and solar wind proton speeds, and present a case study of Carrington Rotation 2064 (December 2007 which includes minor ion (He, Fe, O kinetic and Fe composition parameters in comparison with proton and magnetic field signatures at large-scale structures observed during this interval.

Statistical properties of solar flares and coronal mass ejections through the solar cycle

International Nuclear Information System (INIS)

Telloni, Daniele; Antonucci, Ester; Carbone, Vincenzo; Lepreti, Fabio

2016-01-01

Waiting Time Distributions (WTDs) of solar flares are investigated all through the solar cycle. The same approach applied to Coronal Mass Ejections (CMEs) in a previous work is considered here for flare occurrence. Our analysis reveals that flares and CMEs share some common statistical properties, which result dependent on the level of solar activity. Both flares and CMEs seem to independently occur during minimum solar activity phases, whilst their WTDs significantly deviate from a Poisson function at solar maximum, thus suggesting that these events are correlated. The characteristics of WTDs are constrained by the physical processes generating those eruptions associated with flares and CMEs. A scenario may be drawn in which different mechanisms are actively at work during different phases of the solar cycle. Stochastic processes, most likely related to random magnetic reconnections of the field lines, seem to play a key role during solar minimum periods. On the other hand, persistent processes, like sympathetic eruptions associated to the variability of the photospheric magnetism, are suggested to dominate during periods of high solar activity. Moreover, despite the similar statistical properties shown by flares and CMEs, as it was mentioned above, their WTDs appear different in some aspects. During solar minimum periods, the flare occurrence randomness seems to be more evident than for CMEs. Those persistent mechanisms generating interdependent events during maximum periods of solar activity can be suggested to play a more important role for CMEs than for flares, thus mitigating the competitive action of the random processes, which seem instead strong enough to weaken the correlations among flare event occurrence during solar minimum periods. However, it cannot be excluded that the physical processes at the basis of the origin of the temporal correlation between solar events are different for flares and CMEs, or that, more likely, more sophisticated effects are

Measuring solar reflectance - Part I: Defining a metric that accurately predicts solar heat gain

Energy Technology Data Exchange (ETDEWEB)

Levinson, Ronnen; Akbari, Hashem; Berdahl, Paul [Heat Island Group, Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States)

2010-09-15

Solar reflectance can vary with the spectral and angular distributions of incident sunlight, which in turn depend on surface orientation, solar position and atmospheric conditions. A widely used solar reflectance metric based on the ASTM Standard E891 beam-normal solar spectral irradiance underestimates the solar heat gain of a spectrally selective ''cool colored'' surface because this irradiance contains a greater fraction of near-infrared light than typically found in ordinary (unconcentrated) global sunlight. At mainland US latitudes, this metric R{sub E891BN} can underestimate the annual peak solar heat gain of a typical roof or pavement (slope {<=} 5:12 [23 ]) by as much as 89 W m{sup -2}, and underestimate its peak surface temperature by up to 5 K. Using R{sub E891BN} to characterize roofs in a building energy simulation can exaggerate the economic value N of annual cool roof net energy savings by as much as 23%. We define clear sky air mass one global horizontal (''AM1GH'') solar reflectance R{sub g,0}, a simple and easily measured property that more accurately predicts solar heat gain. R{sub g,0} predicts the annual peak solar heat gain of a roof or pavement to within 2 W m{sup -2}, and overestimates N by no more than 3%. R{sub g,0} is well suited to rating the solar reflectances of roofs, pavements and walls. We show in Part II that R{sub g,0} can be easily and accurately measured with a pyranometer, a solar spectrophotometer or version 6 of the Solar Spectrum Reflectometer. (author)

Measuring solar reflectance Part I: Defining a metric that accurately predicts solar heat gain

Energy Technology Data Exchange (ETDEWEB)

Levinson, Ronnen; Akbari, Hashem; Berdahl, Paul

2010-05-14

Solar reflectance can vary with the spectral and angular distributions of incident sunlight, which in turn depend on surface orientation, solar position and atmospheric conditions. A widely used solar reflectance metric based on the ASTM Standard E891 beam-normal solar spectral irradiance underestimates the solar heat gain of a spectrally selective 'cool colored' surface because this irradiance contains a greater fraction of near-infrared light than typically found in ordinary (unconcentrated) global sunlight. At mainland U.S. latitudes, this metric RE891BN can underestimate the annual peak solar heat gain of a typical roof or pavement (slope {le} 5:12 [23{sup o}]) by as much as 89 W m{sup -2}, and underestimate its peak surface temperature by up to 5 K. Using R{sub E891BN} to characterize roofs in a building energy simulation can exaggerate the economic value N of annual cool-roof net energy savings by as much as 23%. We define clear-sky air mass one global horizontal ('AM1GH') solar reflectance R{sub g,0}, a simple and easily measured property that more accurately predicts solar heat gain. R{sub g,0} predicts the annual peak solar heat gain of a roof or pavement to within 2 W m{sup -2}, and overestimates N by no more than 3%. R{sub g,0} is well suited to rating the solar reflectances of roofs, pavements and walls. We show in Part II that R{sub g,0} can be easily and accurately measured with a pyranometer, a solar spectrophotometer or version 6 of the Solar Spectrum Reflectometer.

Near-term Forecasting of Solar Total and Direct Irradiance for Solar Energy Applications

Science.gov (United States)

Long, C. N.; Riihimaki, L. D.; Berg, L. K.

2012-12-01

Integration of solar renewable energy into the power grid, like wind energy, is hindered by the variable nature of the solar resource. One challenge of the integration problem for shorter time periods is the phenomenon of "ramping events" where the electrical output of the solar power system increases or decreases significantly and rapidly over periods of minutes or less. Advance warning, of even just a few minutes, allows power system operators to compensate for the ramping. However, the ability for short-term prediction on such local "point" scales is beyond the abilities of typical model-based weather forecasting. Use of surface-based solar radiation measurements has been recognized as a likely solution for providing input for near-term (5 to 30 minute) forecasts of solar energy availability and variability. However, it must be noted that while fixed-orientation photovoltaic panel systems use the total (global) downwelling solar radiation, tracking photovoltaic and solar concentrator systems use only the direct normal component of the solar radiation. Thus even accurate near-term forecasts of total solar radiation will under many circumstances include inherent inaccuracies with respect to tracking systems due to lack of information of the direct component of the solar radiation. We will present examples and statistical analyses of solar radiation partitioning showing the differences in the behavior of the total/direct radiation with respect to the near-term forecast issue. We will present an overview of the possibility of using a network of unique new commercially available total/diffuse radiometers in conjunction with a near-real-time adaptation of the Shortwave Radiative Flux Analysis methodology (Long and Ackerman, 2000; Long et al., 2006). The results are used, in conjunction with persistence and tendency forecast techniques, to provide more accurate near-term forecasts of cloudiness, and both total and direct normal solar irradiance availability and

Development of 12.5 m² Solar Collector Panel for Solar Heating Plants

DEFF Research Database (Denmark)

Vejen, Niels Kristian; Furbo, Simon; Shah, Louise Jivan

2004-01-01

and large solar heating systems. Based on the theoretical findings a prototype of an improved HT solar collector was built and tested side-by-side with the original HT solar collector. The improved HT collector makes use of a changed insulation material, an absorber with improved absorptance and emittance......Theoretical and experimental investigations have elucidated how different changes in the design of the 12.5 m(2) HT flat-plate solar collector from the Danish company ARCON Solvarme A/S influence the solar collector efficiency and the yearly thermal performance. The collector is designed for medium...

Solar prominences

CERN Document Server

Engvold, Oddbjørn

2015-01-01

This volume presents the latest research results on solar prominences, including new developments on e.g. chirality, fine structure, magnetism, diagnostic tools and relevant solar plasma physics. In 1875 solar prominences, as seen out of the solar limb, were described by P.A. Secchi in his book Le Soleil as "gigantic pink or peach-flower coloured flames". The development of spectroscopy, coronagraphy and polarimetry brought tremendous observational advances in the twentieth century. The authors present and discuss exciting new challenges (resulting from observations made by space and ground-based telescopes in the 1990s and the first decade of the 21st century) concerning the diagnostics of prominences, their formation, their life time and their eruption along with their impact in the heliosphere (including the Earth). The book starts with a general introduction of the prominence “object” with some historical background on observations and instrumentation. In the next chapter, the various forms of promine...

Cowpea Mosaic Virus-Encoded Protease Does Not Recognize Primary Translation Products of M RNAs from Other Comoviruses

OpenAIRE

Goldbach, Rob; Krijt, Jette

1982-01-01

The protease encoded by the large (B) RNA segment of cowpea mosaic virus was tested for its ability to recognize the in vitro translation products of the small (M) RNA segment from the comoviruses squash mosaic virus, red clover mottle virus, and cowpea severe mosaic virus (CPsMV, strains Dg and Ark), and from the nepovirus tomato black ring virus. Like M RNA from cowpea mosaic virus, the M RNAs from squash mosaic virus, red clover mottle virus, CPsMV-Dg, and CPsMV-Ark were all translated int...

Solar Leasing Summary, Houston Texas

Energy Technology Data Exchange (ETDEWEB)

Hammer, Mary [City of San Antonio, TX (United States)

2013-02-14

A relatively new option for homeowners looking to add solar to their home is the solar lease. At present, the solar lease option can be found in California, Arizona, Texas, Colorado, Hawaii, New York and Oregon. The most active companies currently offering solar leases are NRG Energy, Sungevity, Solar City and Sun Run. With the uncertainty and/or lack of subsidies the states participating in these programs have ebbed and flowed over the last few years. However, there is an expectation that in the current market solar leasing will make solar viable without the utility and federal subsidies. NRG Energy is currently testing this expectation in Houston, TX where currently no subsidies or incentives beyond the federal tax incentives, exist. Following is an explanation on the state of solar leasing in Houston, TX and explanation of the current financing options.

Direct observations of low-energy solar electrons associated with a type 3 solar radio burst

Science.gov (United States)

Frank, L. A.; Gurnett, D. A.

1972-01-01

On 6 April 1971 a solar X-ray flare and a type 3 solar radio noise burst were observed with instrumentation on the eccentric-orbiting satellite IMP 6. The type 3 solar radio noise burst was detected down to a frequency of 31 kHz. A highly anisotropic packet of low-energy solar electron intensities arrived at the satellite approximately 6000 seconds after the onset of the solar flare. This packet of solar electron intensities was observed for 4200 seconds. Maximum differential intensities of the solar electrons were in the energy range of one to several keV. The frequency drift rate of the type 3 radio noise at frequencies below 178 kHz also indicated an average particle speed corresponding to that of a 3-keV electron. The simultaneous observations of these solar electron intensities and of the type 3 solar radio burst are presented, and their interrelationships are explored.

Solar desalination system of combined solar still and humidification-dehumidification unit

Science.gov (United States)

Ghazy, Ahmed; Fath, Hassan E. S.

2016-11-01

Solar stills, as a simple technology, have many advantages such as simple design; unsophisticated fabrication; low capital and operation costs and easily maintained. However, their low daily production has put constraints on their usage. A radical improvement in the performance of solar stills can be achieved by the partial recovery of the energy losses from the glass cover of the still. This paper simulates a direct solar distillation system of combined solar still with an air heating humidification-dehumidification (HDH) sub-system. The main objective of the Still-HDH system is to improve the productivity and thermal efficiency of the conventional solar still by partially recovering the still energy losses to the ambient for additional water production. Various procedures have been employed to improve the thermal performance of the integrated system by recovering heat losses from one component in another component of the system. Simulations have been carried out for the performance of the Still-HDH system under different weather conditions. A comparison has been held between the Still-HDH system and a conventional solar still of the same size and under the same operating conditions.

Developing solar energy in France

International Nuclear Information System (INIS)

Alary-Grall, L.

2003-01-01

3 years ago the 'Soleil' program was launched and today 660.000 m 2 of solar cells have been installed which has made France to rank 4 behind Germany, Greece and Austria in terms of the use of solar energy. The 'Soleil' program, that will end in 2006, aims at developing solar energy in France and is composed of 4 axis: 1) the contribution to the funding of solar equipment through enticing financial helps, 2) the implementation of a quality plan for the installers of solar equipment, 3) the setting of a quality label for innovative and efficient solar equipment and 4) the promoting of solar energy to the professionals of the construction sector. (A.C.)

Solar Cell and Array Technology Development for NASA Solar Electric Propulsion Missions

Science.gov (United States)

Piszczor, Michael; McNatt, Jeremiah; Mercer, Carolyn; Kerslake, Tom; Pappa, Richard

2012-01-01

NASA is currently developing advanced solar cell and solar array technologies to support future exploration activities. These advanced photovoltaic technology development efforts are needed to enable very large (multi-hundred kilowatt) power systems that must be compatible with solar electric propulsion (SEP) missions. The technology being developed must address a wide variety of requirements and cover the necessary advances in solar cell, blanket integration, and large solar array structures that are needed for this class of missions. Th is paper will summarize NASA's plans for high power SEP missions, initi al mission studies and power system requirements, plans for advanced photovoltaic technology development, and the status of specific cell and array technology development and testing that have already been conducted.

solar thermal power systems advanced solar thermal technology project, advanced subsystems development

Science.gov (United States)

1979-01-01

The preliminary design for a prototype small (20 kWe) solar thermal electric generating unit was completed, consisting of several subsystems. The concentrator and the receiver collect solar energy and a thermal buffer storage with a transport system is used to provide a partially smoothed heat input to the Stirling engine. A fossil-fuel combustor is included in the receiver designs to permit operation with partial or no solar insolation (hybrid). The engine converts the heat input into mechanical action that powers a generator. To obtain electric power on a large scale, multiple solar modules will be required to operate in parallel. The small solar electric power plant used as a baseline design will provide electricity at remote sites and small communities.

Solar Market Research and Analysis Publications | Solar Research | NREL

Science.gov (United States)

Market Research and Analysis Publications Solar Market Research and Analysis Publications NREL researchers and analysts publish a variety of documents related to solar market research and analysis achieving the SETO 2030 residential PV cost target of $0.05 /kWh by identifying and quantifying cost

Hydrogen from solar energy

Energy Technology Data Exchange (ETDEWEB)

1977-04-01

The long-range options of energy sources are the breeding reactor, nuclear fusion, and solar energy. Concerning solar energy three systems are being developed: First the photovoltaic cells which are almost ready for industrial production, but which are still too expensive - at least today. Secondly the thermal utilization of solar radiation. Compared to these, thirdly, the photobiological and photochemical possibilities of solar energy utilization have been somewhat neglected so far. However, the photolysis of water by solar energy is a very promising option for future energy demands. This can be done by making use of the photo-synthetic splitting of water in technical facilities or with semiconductors.

THE RISE AND FALL OF OPEN SOLAR FLUX DURING THE CURRENT GRAND SOLAR MAXIMUM

International Nuclear Information System (INIS)

Lockwood, M.; Rouillard, A. P.; Finch, I. D.

2009-01-01

We use geomagnetic activity data to study the rise and fall over the past century of the solar wind flow speed V SW , the interplanetary magnetic field strength B, and the open solar flux F S . Our estimates include allowance for the kinematic effect of longitudinal structure in the solar wind flow speed. As well as solar cycle variations, all three parameters show a long-term rise during the first half of the 20th century followed by peaks around 1955 and 1986 and then a recent decline. Cosmogenic isotope data reveal that this constitutes a grand maximum of solar activity which began in 1920, using the definition that such grand maxima are when 25-year averages of the heliospheric modulation potential exceeds 600 MV. Extrapolating the linear declines seen in all three parameters since 1985, yields predictions that the grand maximum will end in the years 2013, 2014, or 2027 using V SW , F S , or B, respectively. These estimates are consistent with predictions based on the probability distribution of the durations of past grand solar maxima seen in cosmogenic isotope data. The data contradict any suggestions of a floor to the open solar flux: we show that the solar minimum open solar flux, kinematically corrected to allow for the excess flux effect, has halved over the past two solar cycles.

Solar energy promises realized?

International Nuclear Information System (INIS)

Oudshoff, B.

2010-01-01

The US market for solar cells grew 36% in 2009. Thousands of new jobs were created, many millions are invested and new businesses see new opportunities. Optimism among investors, incentivising government policy and new technological developments all contribute to these positive developments. This article provides an update of the incentive measures and their effects and a brief overview of the three solar energy technologies: photovoltaic (PV), solar thermal and concentrated solar power (CSP) [nl

Theoretical comparison between solar combisystems based on bikini tanks and tank-in-tank solar combisystems

DEFF Research Database (Denmark)

Yazdanshenas, Eshagh; Furbo, Simon; Bales, Chris

2008-01-01

Theoretical investigations have shown that solar combisystems based on bikini tanks for low energy houses perform better than solar domestic hot water systems based on mantle tanks. Tank-in-tank solar combisystems are also attractive from a thermal performance point of view. In this paper......, theoretical comparisons between solar combisystems based on bikini tanks and tank-in-tank solar combisystems are presented....

A STATISTICAL STUDY OF SOLAR ELECTRON EVENTS OVER ONE SOLAR CYCLE

International Nuclear Information System (INIS)

Wang Linghua; Lin, R. P.; Krucker, Säm; Mason, Glenn M.

2012-01-01

We survey the statistical properties of 1191 solar electron events observed by the WIND 3DP instrument from 300 keV for a solar cycle (1995 through 2005). After taking into account times of high background, the corrected occurrence frequency of solar electron events versus peak flux exhibits a power-law distribution over three orders of magnitude with exponents between –1.0 and –1.6 for different years, comparable to the frequency distribution of solar proton events, microflares, and coronal mass ejections (CMEs), but significantly flatter than that of soft X-ray (SXR) flares. At 40 keV (2.8 keV), the integrated occurrence rate above ∼0.29 (∼330) cm –2 s –1 sr –1 keV –1 near 1 AU is ∼1000 year –1 (∼600 year –1 ) at solar maximum and ∼35 year –1 (∼25 year –1 ) at solar minimum, about an order of magnitude larger than the observed occurrence rate. We find these events typically extend over ∼45° in longitude, implying the occurrence rate over the whole Sun is ∼10 4 year –1 near solar maximum. The observed solar electron events have a 98.75% association with type III radio bursts, suggesting all type III bursts may be associated with a solar electron event. They have a close (∼76%) association with the presence of low-energy (∼0.02-2 MeV nucleon –1 ), 3 He-rich ( 3 He/ 4 He ≥ 0.01) ion emissions measured by the ACE ULEIS instrument. For these electron events, only ∼35% are associated with a reported GOES SXR flare, but ∼60% appear to be associated with a CME, with ∼50% of these CMEs being narrow. These electrons are often detected down to below 1 keV, indicating a source high in the corona.

8 years of Solar Spectral Irradiance Observations from the ISS with the SOLAR/SOLSPEC Instrument

Science.gov (United States)

Damé, L.; Bolsée, D.; Meftah, M.; Irbah, A.; Hauchecorne, A.; Bekki, S.; Pereira, N.; Cessateur, G.; Marchand, M.; Thiéblemont, R.; Foujols, T.

2016-12-01

Accurate measurements of Solar Spectral Irradiance (SSI) are of primary importance for a better understanding of solar physics and of the impact of solar variability on climate (via Earth's atmospheric photochemistry). The acquisition of a top of atmosphere reference solar spectrum and of its temporal and spectral variability during the unusual solar cycle 24 is of prime interest for these studies. These measurements are performed since April 2008 with the SOLSPEC spectro-radiometer from the far ultraviolet to the infrared (166 nm to 3088 nm). This instrument, developed under a fruitful LATMOS/BIRA-IASB collaboration, is part of the Solar Monitoring Observatory (SOLAR) payload, externally mounted on the Columbus module of the International Space Station (ISS). The SOLAR mission, with its actual 8 years duration, will cover almost the entire solar cycle 24. We present here the in-flight operations and performances of the SOLSPEC instrument, including the engineering corrections, calibrations and improved know-how procedure for aging corrections. Accordingly, a SSI reference spectrum from the UV to the NIR will be presented, together with its UV variability, as measured by SOLAR/SOLSPEC. Uncertainties on these measurements and comparisons with other instruments will be briefly discussed.

Solar heating of the produced water of petroleum; Aquecimento solar da agua produzida de petroleo

Energy Technology Data Exchange (ETDEWEB)

Santos, Rogerio Pitanga; Chiavone-Filho, Osvaldo; Bezerra, Magna A. Santos; Melo, Josette Lourdes Sousa de; Oliveira, Jackson Araujo de; Ramos, Rafael E. Moura [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil); Schuhli, Juliana Bregenski; Andrade, Vivian Tavares de [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

2008-07-01

In this work, experimental data of solar heating for common water and saline solution were measured. The solar heater is formed by a flat-plane collector and a thermal reservoir ('boiler'). The objective is to quantify the variation of fluids' temperature, and correlate it to environment variables, especially solar irradiation. Thereby, it is possible to estimate the solar heating of produced water of petroleum. The solar heater is part of a system of treatment of produced water, and its function is to pre-heat the fluid that enters into the solar distiller, increasing the productivity of distilled water. A saline solution that represents produced water was used in the experiments, using sodium chloride (1000 ppm). The experimental data demonstrates that the solar heater is capable to heat the fluid to temperatures close to 70 deg C, reaching temperatures close to 50 deg C even during cloudy days with low solar radiation. Furthermore, the solar collector energy system provides a higher rate of heating and trough of the thermal reservoir the temperature can remain longer. These are important aspects to the integration with solar distillation. (author)

Solar heating of the produced water of petroleum; Aquecimento solar da agua produzida de petroleo

Energy Technology Data Exchange (ETDEWEB)

Santos, Rogerio Pitanga; Chiavone-Filho, Osvaldo; Bezerra, Magna A. Santos; Melo, Josette Lourdes Sousa de; Oliveira, Jackson Araujo de; Ramos, Rafael E. Moura [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil); Schuhli, Juliana Bregenski; Andrade, Vivian Tavares de [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

2008-07-01

In this work, experimental data of solar heating for common water and saline solution were measured. The solar heater is formed by a flat-plane collector and a thermal reservoir ('boiler'). The objective is to quantify the variation of fluids' temperature, and correlate it to environment variables, especially solar irradiation. Thereby, it is possible to estimate the solar heating of produced water of petroleum. The solar heater is part of a system of treatment of produced water, and its function is to pre-heat the fluid that enters into the solar distiller, increasing the productivity of distilled water. A saline solution that represents produced water was used in the experiments, using sodium chloride (1000 ppm). The experimental data demonstrates that the solar heater is capable to heat the fluid to temperatures close to 70 deg C, reaching temperatures close to 50 deg C even during cloudy days with low solar radiation. Furthermore, the solar collector energy system provides a higher rate of heating and trough of the thermal reservoir the temperature can remain longer. These are important aspects to the integration with solar distillation. (author)

Solar Technician Program Blows Hot

Science.gov (United States)

Ziegler, Peg Moran

1977-01-01

A training program for solar heating technicians was initiated at Sonoma State College's School of Environmental Studies for CETA applicants. Among the projects designed and built were a solar alternative energy center, a solar hot water system, and a solar greenhouse. (MF)

Solar Storage Tank Insulation Influence on the Solar Systems Efficiency

Directory of Open Access Journals (Sweden)

Negoitescu Arina

2012-09-01

Full Text Available For the storage tank of a solar system for domestic hot water production was analyzed the insulation thickness and material influence. To this end, it was considered a private house, occupied by 3 persons, located in zone I of thermal radiation, for which has been simulated the domestic hot water production process. The tank outlet hot water temperature was considered of 45°C. For simulation purposes, as insulation materials for the storage tank were taking into account glass wool and polyurethane with various thicknesses. Finally, was carried out the comparative analysis of two types of tanks, in terms of the insulation thickness influence on the solar fraction, annual solar contribution and solar annual productivity. It resulted that polyurethane is the most advantageous from all points of view.

NASA's search for the solar connection. I. [OSO Skylab, Solar Maximum Mission

Science.gov (United States)

Chapman, R. W.

1979-01-01

NASA's solar research, which leans toward the study of the sun as a star, is surveyed. The Orbiting Solar Observatory (OSO) program is covered, which yielded data such as spectras of 140-400 A wavelength of the entire solar disk. Attention is also given to the results obtained by Skylab, such as data showing that whenever a large coronal hole exists near the sun's equator, a stream of high-speed solar wind will be observed at the earth. Finally areas of future research, such as a concerted study of flare phenomenon, are discussed.

Inovasi Peningkatan Efisiensi Panel Surya Berbasis Fresnel Solar Concentrator Dan Solar Tracker

OpenAIRE

Saputra, Muhammad Adhijaya; Azis, Muhammad Fadli

2014-01-01

Indonesia is a tropical country with great potential for solar energy is about 4.5 kWh per m2. However, this potential can not be fully utilized due to the efficiency of solar panels is still very low at around 16%. Various research and development of solar panels has been done in order to get a system with higher efficiency. Starting from the development of constituent materials, the selection of topology until the latest is the change construction design of the solar panels. That is a chang...

Solar cooling systems. Classification and energetic evaluation; Solare Kuehlsysteme. Klassifizierung und energetische Bewertung

Energy Technology Data Exchange (ETDEWEB)

Hennig, Jakob [Technische Univ. Bergakademie Freiberg (Germany); Hafner, Armin [SINTEF Energy Research, Trondheim (Norway); Eikevik, Trygve M. [NTNU, Trondheim (Norway)

2012-07-01

The investigation of alternative, sustainable concepts for cold production is worthwhile in times of increasing energy demand for cooling and air conditioning applications. Energy sources such as solar radiation can help to reduce the burden on the environment and energy networks. Solar electricity from photovoltaic cells or solar power from solar collectors can be used in refrigerating equipment (such as cold vapor compression chiller, absorption chiller, adsorption chillers, open systems, thermo-mechanical systems or ejector-based systems) are fed in order to produce the desired coldness. In many cases, the temporal coincidence of radiation supply and cooling requirements makes the solar cooling to a promising concept, especially at sites with a high solar radiation, large cooling demand, high energy prices, or insufficient access to public power grids. A model-based investigation of different solar cooling systems with an equivalent cooling capacity was carried out. The results show that the performance potential strongly depends on the selected technology and the site of the system. A balanced daily energy balance can be achieved with an appropriately dimensioned solar power plant with cooling concept. Depending on the system and interpretation, primary energy savings or a primary energy overhead can be achieved within a year in comparison to a conventional system.

Performance comparison between silicon solar panel and dye-sensitized solar panel in Malaysia

Science.gov (United States)

Hamed, N. K. A.; Ahmad, M. K.; Urus, N. S. T.; Mohamad, F.; Nafarizal, N.; Ahmad, N.; Soon, C. F.; Ameruddin, A. S.; Faridah, A. B.; Shimomura, M.; Murakami, K.

2017-09-01

In carrying out experimental research in performance between silicon solar panel and dye-sensitive solar panel, we have been developing a device and a system. This system has been developed consisting of controllers, hardware and software. This system is capable to get most of the input sources. If only need to change the main circuit and coding for a different source input value. This device is able to get the ambient temperature, surface temperature, surrounding humidity, voltage with load, current with load, voltage without load and current without load and save the data into external memory. This device is able to withstand the heat and rain as it was fabricated in a waterproof box. This experiment was conducted to examine the performance of both the solar panels which are capable to maintain their stability and performance. A conclusion based on data populated, the distribution of data for dye-sensitized solar panel is much better than silicon solar panel as dye-sensitized solar panel is very sensitive to heat and not depend only on midday where is that is the maximum ambient temperature for both solar panel as silicon solar panel only can give maximum and high output only when midday.

Design of a solar-assisted drying system using the double-pass solar collector

International Nuclear Information System (INIS)

Sopian, K.; Daud, W.R.; Supranto; Othman, M.Y.; Yatim, B.

2000-01-01

A solar-assisted drying system that uses the double-pass solar collector with porous media in the second channel has been designed and constructed at the Solar Energy Research Park, Universiti Kebangsaan Malaysia. The drying system has a total of six double-pass solar collectors. Each collector has a length of 240 cm and a width of 120 cm. The upper channel depth is 3.5 cm and the lower channel depth is 10.5 cm. The lower channel is filled up with steel wool as the porous media. The solar collectors are arranged as 2 banks of 3 collectors each in series. Internal manifold are used to connect the collectors. An auxiliary heater source is installed to supply heat under unfavourable solar radiation conditions. An on/off controller is used to control the startup and shutdown of the auxiliary heater. An outlet temperature of 80-90 0 C can be achieved at a solar radiation range of 800-900 W/m 3 , ambient temperature of 29 degree C and flow rate of O.20 kg/s. (Author)

Solar Physics at Evergreen: Solar Dynamo and Chromospheric MHD

Science.gov (United States)

Zita, E. J.; Maxwell, J.; Song, N.; Dikpati, M.

2006-12-01

We describe our five year old solar physics research program at The Evergreen State College. Famed for its cloudy skies, the Pacific Northwest is an ideal location for theoretical and remote solar physics research activities. Why does the Sun's magnetic field flip polarity every 11 years or so? How does this contribute to the magnetic storms Earth experiences when the Sun's field reverses? Why is the temperature in the Sun's upper atmosphere millions of degrees higher than the Sun's surface temperature? How do magnetic waves transport energy in the Sun’s chromosphere and the Earth’s atmosphere? How does solar variability affect climate change? Faculty and undergraduates investigate questions such as these in collaboration with the High Altitude Observatory (HAO) at the National Center for Atmospheric Research (NCAR) in Boulder. We will describe successful student research projects, logistics of remote computing, and our current physics investigations into (1) the solar dynamo and (2) chromospheric magnetohydrodynamics.

Nice module. Apollon Solar present their new line of solar modules; Nettes Modul. Apollon Solar stellt Linie fuer neuartige Modultechnologie vor

Energy Technology Data Exchange (ETDEWEB)

Podewils, C.

2008-06-15

Solar modules, TGV engines and perfume Zerstaeuber seem to have nothing in common. The new solar module developed by French producer Apollon Solar makes use of both technologies in the construction process. The contribution presents the 'Nice' module which has many new features. (orig.)

Solar thermal aided power generation

International Nuclear Information System (INIS)

Hu, Eric; Yang, YongPing; Nishimura, Akira; Yilmaz, Ferdi; Kouzani, Abbas

2010-01-01

Fossil fuel based power generation is and will still be the back bone of our world economy, albeit such form of power generation significantly contributes to global CO 2 emissions. Solar energy is a clean, environmental friendly energy source for power generation, however solar photovoltaic electricity generation is not practical for large commercial scales due to its cost and high-tech nature. Solar thermal is another way to use solar energy to generate power. Many attempts to establish solar (solo) thermal power stations have been practiced all over the world. Although there are some advantages in solo solar thermal power systems, the efficiencies and costs of these systems are not so attractive. Alternately by modifying, if possible, the existing coal-fired power stations to generate green sustainable power, a much more efficient means of power generation can be reached. This paper presents the concept of solar aided power generation in conventional coal-fired power stations, i.e., integrating solar (thermal) energy into conventional fossil fuelled power generation cycles (termed as solar aided thermal power). The solar aided power generation (SAPG) concept has technically been derived to use the strong points of the two technologies (traditional regenerative Rankine cycle with relatively higher efficiency and solar heating at relatively low temperature range). The SAPG does not only contribute to increase the efficiencies of the conventional power station and reduce its emission of the greenhouse gases, but also provides a better way to use solar heat to generate the power. This paper presents the advantages of the SAPG at conceptual level.

Solar Photovoltaic Technology Basics | NREL

Science.gov (United States)

Photovoltaic Technology Basics Solar Photovoltaic Technology Basics Solar cells, also called found in sand) created an electric charge when exposed to sunlight. Soon solar cells were being used to power space satellites and smaller items like calculators and watches. Photo of a large silicon solar

Solar thermal utilization--an overview

International Nuclear Information System (INIS)

Chen Deming; Xu Gang

2007-01-01

Solar energy is an ideal renewable energy source and its thermal utilization is one of its most important applications. We review the status of solar thermal utilization, including: (1) developed technologies which are already widely used all over the world, such as solar assisted water heaters, solar cookers, solar heated buildings and so on; (2) advanced technologies which are still in the development or laboratory stage and could have more innovative applications, including thermal power generation, refrigeration, hydrogen production, desalination, and chimneys; (3) major problems which need to be resolved for advanced utilizaiton of solar thermal energy. (authors)

Solar Radiation Model for Development and Control of Solar Energy Sources

Directory of Open Access Journals (Sweden)

Dominykas Vasarevičius

2016-06-01

Full Text Available The model of solar radiation, which takes into account direct, diffused and reflected components of solar energy, has been presented. Model is associated with geographical coordinates and local time of every day of the year. It is shown that using analytic equations for modelling the direct component, it is possible to adopt it for embedded systems with low computational power and use in solar tracking applications. Reflected and diffused components are especially useful in determining the performance of photovoltaic modules in certain location and surroundings. The statistical method for cloud layer simulation based on local meteorological data is offered. The presented method can’t be used for prediction of weather conditions but it provides patterns of solar radiation in time comparable to those measured with pyranometer. Cloud layer simulation together with total solar radiation model is a useful tool for development and analysis of maximum power point tracking controllers for PV modules.

Solar radiation for sea-water desalination and electric power generation via vacuum solar collectors

International Nuclear Information System (INIS)

Mottinelli, L.; Reali, M.; El-Nashar, A.M.; Giusiano, F.; Vigotti, R.

1996-01-01

The present report concerns the energetic potential of vacuum solar which are rather versatile and efficient devices for converting solar energy into thermal energy. Two main energetic applications have been analysed: the first one for a solar sea water desalination plant which has been operated in Abu Dhabi for the past ten years, the other for a conceptual solar thermoelectric-power plant having a fair thermodynamic efficiency (15-20%). A simple technology for the manufacture of vacuum solar collectors in a standard mechanical shop is being developed in collaboration between ENEL Sp A (DSR-CRIS, Milano) and WED (Abu Dhabi). Such technology should have an important economy-saving potential per se and would also make repair and substitution operations simple enough for the actual operators of the vacuum solar collector system without any need of external assistance. The technic-operative-economical features of the Abu Dhabi solar desalination plant suggest that the use novel simplified vacuum solar collectors could have a considerable technic economical potential. The analysis of the conceptual solar thermo-electric-power plant focuses on its general layout and singles out key technological issues which ought to be addressed in an overall feasibility study. 5 figs., 3 tabs

Meteorology ans solar physics

Science.gov (United States)

Schwarz, Oliver

When in the second half of the 19th century both solar physics and astrophysics came into existence, various solar phenomena were described by analogies encountered in the terrestrial atmosphere. For a certain time, meteorology played a central role in research on solar processes. At first glance, this may appear as a curious and old-fashioned specialty. However, solar physics owes its first insights into solar structure to various analogies in terrestrial atmospheric studies. The present investigation intends to elucidate this fact, to present details of the historical development, and to demonstrate how our present knowledge in certain fields is based on considerations which were originally taken from the description of the terrestrial atmosphere.

A Little Solar Story

DEFF Research Database (Denmark)

Ahmad, Bashir

1997-01-01

Experiences from use of solar cookers in India and many other places are different. But the story which is based on a field study in Gujarat state of India shows that during last twenty years there has been a tendency that many families do not continue to use their solar cookers. The study shows...... that the tendency is related with the lack of compatibility of this new technology (solar cooker) with the everyday real-life conditions of the families. In principle the findings are supported by an evaluation report on a solar cooker project in Burkina Faso. The conclusion is that the user should be involved...... in the solar cooker technological development process....

Solar heating cooling. Preparation of possible participation in IEA, Solar Heating Cooling Task 25

International Nuclear Information System (INIS)

2001-03-01

For the Danish solar heating industries it is interesting to discuss the domestic market possibilities and the export possibilities for solar heating cooling systems. The Danish solar heating sector also wants to participate in the international collaboration within IEA Solar Heating and Cooling Task 25 'Solar Assisted Air Conditioning of Buildings'. The Danish Energy Agency therefore has granted means for this project to discuss: The price of cooling for 3 different solar cooling methods (absorption cooling, desiccant cooling and ejector cooling); Market possibilities in Denmark and abroad; The advantages by Danish participation in IEA Task 25. The task has been solved through literature studies to establish status for the 3 technologies. It turned out that ejector cooling by low temperatures (85 deg. C from the solar collector) exists as pilot plants in relation to district heating, but is still not commercial accessible. Desiccant cooling, where the supplied heat has temperatures down to 55 deg. C is a well-developed technology. However only a handful of pilot plants with solar heating exists, and thus optimization relating to operation strategy and economy is on the experimental stage. Absorption cooling plants driven by solar heating are found in a large number in Japan and are also demonstrated in several other countries. The combination of absorption heating pump and solar heating is considered to be commercial accessible. Solar heating is interesting as heat source of to the extent that it can replace other sources of heat without the economy being depreciated. This can be the case in South Europe if: 1) oil or natural gas is used for heating; 2) a solar heating system already exists, e.g. for domestic water supply, and is installed so that the marginal costs by solar heating supply of the ventilation plant is reduced. All in all the above conditions mean that the market for solar heating for cooling is very limited in Europe, where almost everybody are

Sunmotor Solar Shack 120

International Nuclear Information System (INIS)

Jensen, E.

2009-01-01

This article described a solar pump that was developed by Alberta-based Sunmotor International Ltd. The prototype Solar Shack 120 was recently deployed in central Alberta for a remediation project for Devon Canada. The portable solar pump unit is well suited for environmental remediation in the oilpatch where conventional electricity is not available. The solar panels automatically run the pump whenever there is enough sunlight and there is liquid in the sump. Devon Canada wanted a system that continues to pump during cloudy weather to avoid the accumulation of effluent in the sump. The Solar Shack 120 delivers 120 volts of alternating current (vac) power. Solar panels are used to charge a bank of large sealed batteries that supply direct power (DC) to an inverter, which converts it into AC. A thermostat control was added to shut off the pumps in cold weather to avoid battery discharging. The Solar Shack unit has possibilities in countries with unreliable electricity supplies. It could provide a backup power supply that automatically kicks in whenever the power grid goes down. Sunmotor International Ltd. can supply complete remote power systems for both AC and DC electrical requirements. The systems are designed for each application to ensure customer satisfaction. The company is currently building a unit that integrates solar power with a generator backup, thereby eliminating the annoying noise of a continually running generator. 1 fig

Roof Integrated Solar Absorbers: The Measured Performance of ''Invisible'' Solar Collectors: Preprint

International Nuclear Information System (INIS)

Colon, C. J.; Merrigan, T.

2001-01-01

The Florida Solar Energy Center (FSEC), with the support of the National Renewable Energy Laboratory, has investigated the thermal performance of solar absorbers that are an integral, yet indistinguishable, part of a building's roof. The first roof-integrated solar absorber (RISA) system was retrofitted into FSEC's Flexible Roof Facility in Cocoa, Florida, in September 1998. This ''proof-of-concept'' system uses the asphalt shingle roof surface and the plywood decking under the shingles as an unglazed solar absorber. Data was gathered for a one-year period on the system performance. In Phase 2, two more RISA prototypes were constructed and submitted for testing. The first used the asphalt shingles on the roof surface with the tubing mounted on the underside of the plywood decking. The second prototype used metal roofing panels over a plywood substrate and placed the polymer tubing between the plywood decking and the metal roofing. This paper takes a first look at the thermal performance results for the ''invisible'' solar absorbers that use the actual roof surface of a building for solar heat collection

Solar variability observed through changes in solar figure and mean diameter

International Nuclear Information System (INIS)

1984-01-01

A program to monitor solar luminosity variations through diameter measurements has been in operation at SCLERA since 1981. The solar diameter is measured at multiple angles from the equator. Measurements at these different angles have the advantage that not only can the solar oblateness be accurately measured, but also, a systematic errors introduced by atmospheric refraction can be reduced to a minimum. An improved theoretical treatment relevant to the relationship between the solar diameter and luminosity for long period oscilations has been successfully developed, and testing is currently underway. The construction of an absolute calibration system for the telescope field has been conducted and will soon be operational. A review of this work is presented

Solar power generating device. Solar denryoku hassei sochi

Energy Technology Data Exchange (ETDEWEB)

Hayashi, E

1990-02-06

Concerning the existing solar power generating device using the analogue sequential partial shunt system, the number of interface line between the solar cell panel and the shunt dissipater is enormous and complicated in addition to the increased temperature rise of the shunt transistor in its working condition. Furthermore, concerning the digital sequential full shunt system, the above temperature rise becomes less, but the above number of interface line is likewise enormous. In order to remove the above defects, the solar power generating device which this invention concerns has the features that, in each row of solar cells connected to shunt transistors which are controlled respectively in a manner of on (saturation)/off independently in accordance with the amount of surplus electric power, the number of parallel connection of the unit cell circuits composing the each row above is made to be the different number respectively. Besides, it is proposed to have the feature in particular that such a number is made to be the number of 2 {sup n} (n is from zero to any integer, m) where n is increased by one progressively. 5 figs.

The New Solar System: China’s Evolving Solar Industry and Its Implications for Competitive Solar Power in the United States and the World

Energy Technology Data Exchange (ETDEWEB)

Ball, Jeffrey [Stanford Univ., CA (United States); Reicher, Dan [Stanford Univ., CA (United States); Sun, Xiaojing [Stanford Univ., CA (United States); Pollock, Caitlin [Stanford Univ., CA (United States)

2017-03-08

Solar power is undergoing a revolution. Over the past decade, an energy source as old as the planet and theoretically all but limitless has plummeted in cost and begun in some places to be harnessed in large volume. This dynamic is disrupting the modern energy system and, as energy disruptions always do, rattling the geopolitical order. In the process, the industry that produces the equipment to convert sunlight into electricity is simultaneously reeling, consolidating, and surging. These twin transformations—one of the global energy system, one of the global solar industry—carry profound implications for national economies and for the planet. At the center of both transformations sits China. The New Solar System illuminates key and little- understood changes that are remaking the solar enterprise—in China and thus in the world. Based on this analysis, it recommends changes in U.S. solar policy—particularly timely with a new U.S. administration and Congress—that would put solar power on a more economically sensible path toward environmentally significant growth. The New Solar System does not seek to enable any country to beat another in the global solar industry. It seeks instead to help all countries find their most effective places. By better understanding and playing to their comparative strengths in the solar business, countries would achieve two key objectives. They would reduce the cost for the world of scaling up solar power. And they would be better positioned to fashion policies that maximized the long-term benefit to their own economies from solar’s global growth.

Proceedings of the CanSIA solar conference 2005 : the world of solar. CD-ROM ed.

International Nuclear Information System (INIS)

2005-01-01

This conference focused on recent activities promoting solar energy as a major energy supplier, as well as on actions needed to overcome barriers to greater solar deployment. The potential of solar energy technologies in overcoming energy supply problems was examined, as well as the value of solar energy in achieving greenhouse gas reduction targets and creating jobs and wealth for local economies. Various solar energy programs in Canada were reviewed, as well as greenhouse gas offset systems and domestic hot water programs. Standard Offer Contracts in Ontario were discussed. Various university and industry partnerships in solar energy research were described. Issues concerning interconnection standards and industry updates were reviewed. Financing programs for solar energy projects were presented, including Renewable Energy Deployment Initiative (REDI) program statistics. Performance standards for photovoltaic (PV) modules were reviewed, as well as changes in various building codes relating to the solar energy industry. Issues concerning sustainable energy education, marketing and training were examined. The role of solar energy in Ontario's electricity supply was discussed. An overview of current solar energy projects funded by the Canadian government was provided. Thirty-nine papers were presented at this conference, of which 5 have been catalogued separately for inclusion in this database. refs., tabs., figs

Solar Maps | Geospatial Data Science | NREL

Science.gov (United States)

Solar Maps Solar Maps These solar maps provide average daily total solar resource information on disability, contact the Geospatial Data Science Team. U.S. State Solar Resource Maps Access state maps of MT NE NV NH NJ NM NY NC ND OH OK OR PA RI SC SD TN TX UT VT VA WA WV WI WY × U.S. Solar Resource

Recent perspectives in solar physics - Elemental composition, coronal structure and magnetic fields, solar activity

Science.gov (United States)

Newkirk, G., Jr.

1975-01-01

Elemental abundances in the solar corona are studied. Abundances in the corona, solar wind and solar cosmic rays are compared to those in the photosphere. The variation in silicon and iron abundance in the solar wind as compared to helium is studied. The coronal small and large scale structure is investigated, emphasizing magnetic field activity and examining cosmic ray generation mechanisms. The corona is observed in the X-ray and EUV regions. The nature of coronal transients is discussed with emphasis on solar-wind modulation of galactic cosmic rays. A schematic plan view of the interplanetary magnetic field during sunspot minimum is given showing the presence of magnetic bubbles and their concentration in the region around 4-5 AU by a fast solar wind stream.

Solar Probe Plus

Science.gov (United States)

Szabo, Adam

2011-01-01

The NASA Solar Probe Plus mission is planned to be launched in 2018 to study the upper solar corona with both.in-situ and remote sensing instrumentation. The mission will utilize 6 Venus gravity assist maneuver to gradually lower its perihelion to 9.5 Rs below the expected Alfven pOint to study the sub-alfvenic solar wind that is still at least partially co-rotates with the Sun. The detailed science objectives of this mission will be discussed. SPP will have a strong synergy with The ESA/NASA Solar orbiter mission to be launched a year ahead. Both missions will focus on the inner heliosphere and will have complimentary instrumentations. Strategies to exploit this synergy will be also presented.

Solar gravitational redshift

International Nuclear Information System (INIS)

Lopresto, J.C.; Chapman, R.D.

1980-01-01

Wavelengths of solar spectrum lines should be shifted toward the red by the Sun's gravitational field as predicted by metric theories of gravity according to the principle of equivalence. Photographic wavelengths of 738 solar Fe 1 lines and their corresponding laboratory wavelengths have been studied. The measured solar wavelength minus the laboratory wavelength (Δlambdasub(observed)) averaged for the strong lines agrees well with the theoretically predicted shift (Δlambdasub(theoretical)). Studies show that the departures depend on line strength. No dependence of the departures on wavelength was found within the existing data. By studying strong lines over a wide spectral range, velocity shifts caused by the complex motions in the solar atmosphere seem to affect the results in a minimal fashion. (orig.)

Photovoltaic solar cell

Science.gov (United States)

Nielson, Gregory N; Okandan, Murat; Cruz-Campa, Jose Luis; Resnick, Paul J

2013-11-26

A photovoltaic solar cell for generating electricity from sunlight is disclosed. The photovoltaic solar cell comprises a plurality of spaced-apart point contact junctions formed in a semiconductor body to receive the sunlight and generate the electicity therefrom, the plurality of spaced-apart point contact junctions having a first plurality of regions having a first doping type and a second plurality of regions having a second doping type. In addition, the photovoltaic solar cell comprises a first electrical contact electrically connected to each of the first plurality of regions and a second electrical contact electrically connected to each of the second plurality of regions, as well as a passivation layer covering major surfaces and sidewalls of the photovoltaic solar cell.

Advanced Solar Panel Designs

Science.gov (United States)

Ralph, E. L.; Linder, E. B.

1995-01-01

Solar panel designs that utilize new high-efficiency solar cells and lightweight rigid panel technologies are described. The resulting designs increase the specific power (W/kg) achievable in the near-term and are well suited to meet the demands of higher performance small satellites (smallsats). Advanced solar panel designs have been developed and demonstrated on two NASA SBIR contracts at Applied Solar. The first used 19% efficient, large area (5.5 cm x 6.5 cm) GaAs/Ge solar cells with a lightweight rigid graphite epoxy isogrid substrate configuration. A 1,445 sq cm coupon was fabricated and tested to demonstrate 60 W/kg with a high potential of achieving 80 W/kg. The second panel design used new 22% efficiency, dual-junction GaInP2/GaAs/Ge solar cells combined with a lightweight aluminum core/graphite fiber mesh facesheet substrate. A 1,445 sq cm coupon was fabricated and tested to demonstrate 105 W/kg with the potential of achieving 115 W/kg.

Solar energy perspectives in France

International Nuclear Information System (INIS)

2008-01-01

In a context combining climate change, energy supply crisis, an increased interest in solar energy, a strongly increasing market of solar installations, new technologies, a promotion of the development of the use solar energy in France and a fast development of the water heater and photovoltaic generator markets in France, this report proposes a wide overview of the past, present and future development of solar energy. It discusses the evolution of the French national energy policy and of the solar energy within this policy. It presents and discusses the solar energy resources, their strengths and weaknesses, their geographical and time distribution. It describes the various uses and applications of solar energy in buildings, discusses different aspects of this market (actors, economical data, evolutions, public incentives, perspectives). Then, it describes and discusses technical and economical aspects of two important technologies, the photovoltaic solar energy and the thermodynamic conversion of solar energy. Public incentives, laws and regulations, technical and economic aspects of the connection to the distribution network are then discussed. Some recommendations and ideas are formulated concerning research activities, industrial development, quality of equipment and facilities, personnel education, investment needs

Solar Flare Aimed at Earth

Science.gov (United States)

2002-01-01

At the height of the solar cycle, the Sun is finally displaying some fireworks. This image from the Solar and Heliospheric Observatory (SOHO) shows a large solar flare from June 6, 2000 at 1424 Universal Time (10:24 AM Eastern Daylight Savings Time). Associated with the flare was a coronal mass ejection that sent a wave of fast moving charged particles straight towards Earth. (The image was acquired by the Extreme ultaviolet Imaging Telescope (EIT), one of 12 instruments aboard SOHO) Solar activity affects the Earth in several ways. The particles generated by flares can disrupt satellite communications and interfere with power transmission on the Earth's surface. Earth's climate is tied to the total energy emitted by the sun, cooling when the sun radiates less energy and warming when solar output increases. Solar radiation also produces ozone in the stratosphere, so total ozone levels tend to increase during the solar maximum. For more information about these solar flares and the SOHO mission, see NASA Science News or the SOHO home page. For more about the links between the sun and climate change, see Sunspots and the Solar Max. Image courtesy SOHO Extreme ultaviolet Imaging Telescope, ESA/NASA

Solar ultraviolet hazards

International Nuclear Information System (INIS)

Azmah Ali

1995-01-01

The paper discussed the following subjects: the sources of ultraviolet radiation, solar ultraviolet radiation definition, effects of over exposure to solar ultraviolet radiation, exposure limits and radiation protection of this radiation

Solar Sprint

Science.gov (United States)

Tabor, Richard; Anderson, Stephen

2007-01-01

In the "Solar Sprint" activity, students design, test, and race a solar-powered car built with Legos. The use of ratios is incorporated to simulate the actual work of scientists and engineers. This method encourages fourth-grade students to think about multiple variables and stimulates their curiosity when an activity doesn't come out as…

Development of practical solar-electric vehicle; Jitsuyo fukyugata solar denki jidosha no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Saito, S; Fujinaka, M [Tokyo Denki University, Tokyo (Japan)

1997-11-25

The paper reported on a Tokyo-Nagoya travel test on a practical spread type solar-electric vehicle, Solar-EV. A comparative study was made running the same type gasoline vehicle, GV. The measured power consumption amount of Solar-EV is 57.6 kWh. By converting it into Mcal unit, an energy consumption amount of 49.5 Mcal was obtained. Further, as to GV, the energy consumption amount of 316 Mcal was obtained using the amount of supply of gasoline (mean heating value: 8.4 Mcal/h) of 37.6 l and the fuel consumption of 16.2 km/l. Accordingly, the energy consumption amount of Solar-EV became a sixth of that of GV. In the cost comparison, the cost of Solar-EV was 1,440 yen (power source price: 25 yen/kWh), which is about a third of that of GV, 3760 yen (gasoline unit price: 100 yen/l). Monocrystal Si solar cells, 270W, installed on hood/roof are connected to the main 288V system (the auxiliary 12V system is amorphous Si), and generate power 4.4 kWh during travel. A total power consumption amount of Solar-EV in the total travel (Tokyo-Nagoya) is 79.9 kWh including the auxiliary system, approximately 6% of which was to be supplied from solar cells. 1 ref., 6 figs., 3 tabs.

THREE-DIMENSIONAL EVOLUTION OF SOLAR WIND DURING SOLAR CYCLES 22–24

International Nuclear Information System (INIS)

Manoharan, P. K.

2012-01-01

This paper presents an analysis of three-dimensional evolution of solar wind density turbulence and speed at various levels of solar activity between solar cycles 22 and 24. The solar wind data used in this study have been obtained from the interplanetary scintillation (IPS) measurements made at the Ooty Radio Telescope, operating at 327 MHz. Results show that (1) on average, there was a downward trend in density turbulence from the maximum of cycle 22 to the deep minimum phase of cycle 23; (2) the scattering diameter of the corona around the Sun shrunk steadily toward the Sun, starting from 2003 to the smallest size at the deepest minimum, and it corresponded to a reduction of ∼50% in the density turbulence between the maximum and minimum phases of cycle 23; (3) the latitudinal distribution of the solar wind speed was significantly different between the minima of cycles 22 and 23. At the minimum phase of solar cycle 22, when the underlying solar magnetic field was simple and nearly dipole in nature, the high-speed streams were observed from the poles to ∼30° latitudes in both hemispheres. In contrast, in the long-decay phase of cycle 23, the sources of the high-speed wind at both poles, in accordance with the weak polar fields, occupied narrow latitude belts from poles to ∼60° latitudes. Moreover, in agreement with the large amplitude of the heliospheric current sheet, the low-speed wind prevailed in the low- and mid-latitude regions of the heliosphere. (4) At the transition phase between cycles 23 and 24, the high levels of density and density turbulence were observed close to the heliospheric equator and the low-speed solar wind extended from the equatorial-to-mid-latitude regions. The above results in comparison with Ulysses and other in situ measurements suggest that the source of the solar wind has changed globally, with the important implication that the supply of mass and energy from the Sun to the interplanetary space has been significantly reduced

Solar Neutrinos

Directory of Open Access Journals (Sweden)

V. Antonelli

2013-01-01

relevant indications on the fundamental interactions among particles. After reviewing the striking results of the last two decades, which were determinant to solve the long standing solar neutrino puzzle and refine the Standard Solar Model, we focus our attention on the more recent results in this field and on the experiments presently running or planned for the near future. The main focus at the moment is to improve the knowledge of the mass and mixing pattern and especially to study in detail the lowest energy part of the spectrum, which represents most of the solar neutrino spectrum but is still a partially unexplored realm. We discuss this research project and the way in which present and future experiments could contribute to make the theoretical framework more complete and stable, understanding the origin of some “anomalies” that seem to emerge from the data and contributing to answer some present questions, like the exact mechanism of the vacuum to matter transition and the solution of the so-called solar metallicity problem.

Solar satellites

Energy Technology Data Exchange (ETDEWEB)

Poher, C.

1982-01-01

A reference system design, projected costs, and the functional concepts of a satellite solar power system (SSPS) for converting sunlight falling on solar panels of a satellite in GEO to a multi-GW beam which could be received by a rectenna on earth are outlined. Electricity transmission by microwaves has been demonstrated, and a reference design system for supplying 5 GW dc to earth was devised. The system will use either monocrystalline Si or concentrator GaAs solar cells for energy collection in GEO. Development is still needed to improve the lifespan of the cells. Currently, the cell performance degrades 50 percent in efficiency after 7-8 yr in space. Each SSPS satellite would weigh either 34,000 tons (Si) or 51,000 tons (GaAs), thereby requiring the fabrication of a heavy lift launch vehicle or a single-stage-to-orbit transport in order to minimize launch costs. Costs for the solar panels have been estimated at $500/kW using the GaAs technology, with transport costs for materials to GEO being $40/kg.

Solar satellites

Science.gov (United States)

Poher, C.

A reference system design, projected costs, and the functional concepts of a satellite solar power system (SSPS) for converting sunlight falling on solar panels of a satellite in GEO to a multi-GW beam which could be received by a rectenna on earth are outlined. Electricity transmission by microwaves has been demonstrated, and a reference design system for supplying 5 GW dc to earth was devised. The system will use either monocrystalline Si or concentrator GaAs solar cells for energy collection in GEO. Development is still needed to improve the lifespan of the cells. Currently, the cell performance degrades 50 percent in efficiency after 7-8 yr in space. Each SSPS satellite would weigh either 34,000 tons (Si) or 51,000 tons (GaAs), thereby requiring the fabrication of a heavy lift launch vehicle or a single-stage-to-orbit transport in order to minimize launch costs. Costs for the solar panels have been estimated at $500/kW using the GaAs technology, with transport costs for materials to GEO being $40/kg.

Alternatives in solar energy

Science.gov (United States)

Schueler, D. G.

1978-01-01

Although solar energy has the potential of providing a significant source of clean and renewable energy for a variety of applications, it is expected to penetrate the nation's energy economy very slowly. The alternative solar energy technologies which employ direct collection and conversion of solar radiation as briefly described.

Solar Filament Extraction and Characterizing

Science.gov (United States)

Yuan, Yuan; Shih, F. Y.; Jing, J.; Wang, H.

2010-05-01

This paper presents a new method to extract and characterize solar filaments from H-alpha full-disk images produced by Big Bear Solar Observatory. A cascading Hough Transform method is designed to identify solar disk center location and radius. Solar disks are segmented from the background, and unbalanced illumination on the surface of solar disks is removed using polynomial surface fitting. And then a localized adaptive thresholding is employed to extract solar filament candidates. After the removal of small solar filament candidates, the remaining larger candidates are used as the seeds of region growing. The procedure of region growing not only connects broken filaments but also generate complete shape for each filament. Mathematical morphology thinning is adopted to produce the skeleton of each filament, and graph theory is used to prune branches and barbs to get the main skeleton. The length and the location of the main skeleton is characterized. The proposed method can help scientists and researches study the evolution of solar filament, for instance, to detect solar filament eruption. The presented method has already been used by Space Weather Research Lab of New Jersey Institute of Technology (http://swrl.njit.edu) to generate the solar filament online catalog using H-alpha full-disk images of Global H-alpha Network (http://swrl.njit.edu/ghn_web/).

A Shocking Solar Nebula?

OpenAIRE

Liffman, Kurt

2009-01-01

It has been suggested that shock waves in the solar nebula formed the high temperature materials observed in meteorites and comets. It is shown that the temperatures at the inner rim of the solar nebula could have been high enough over a sufficient length of time to produce chondrules, CAIs, refractory dust grains and other high-temperature materials observed in comets and meteorites. The solar bipolar jet flow may have produced an enrichment of 16O in the solar nebula over time and the chond...

The Solar Bank concept

International Nuclear Information System (INIS)

Eckhart, M.T.

1999-01-01

The Solar Bank is proposed to be established as a multinational wholesale lending institution supporting the adoption of solar photovoltaic (PV) systems by as much as 40% of the world's population. It would supply capital resources to local lending institutions such as banks, credit unions, cooperatives, and rural lending organizations in the developing countries, and to financial institutions in the developed countries. The Solar Bank is intended to be global in scope, with operations in the major countries. The Solar Bank will bring a degree of standardization to the process of making small loans to many people for the purchase of PV systems, and it will provide technical support and training to its participating financial institutions. 'Solar Bank International' is likely to be headquartered in Europe. (orig.)

The sun and solar flares

International Nuclear Information System (INIS)

McKenna-Lawlor, S.

1982-01-01

The subject is discussed under the headings: the sun's core (thermonuclear reactions, energy transfer from core through radiation zone, convection zone, photosphere, chromosphere and corona); the photosphere (convection, granulation, sunspots, magnetic fields, solar cycle, rotation of the sun); solar variability and paleoclimatic records (correlation of low solar activity with increased 14 C production in atmosphere); the chromosphere and corona (turbulence, temperature, coronal streamers, energy transfer); solar flares (cosmic rays, aurorae, spectra, velocity of flares, prominences, mechanisms of flares); the solar wind. (U.K.)

Weakest solar wind of the space age and the current 'MINI' solar maximum

International Nuclear Information System (INIS)

McComas, D. J.; Angold, N.; Elliott, H. A.; Livadiotis, G.; Schwadron, N. A.; Smith, C. W.; Skoug, R. M.

2013-01-01

The last solar minimum, which extended into 2009, was especially deep and prolonged. Since then, sunspot activity has gone through a very small peak while the heliospheric current sheet achieved large tilt angles similar to prior solar maxima. The solar wind fluid properties and interplanetary magnetic field (IMF) have declined through the prolonged solar minimum and continued to be low through the current mini solar maximum. Compared to values typically observed from the mid-1970s through the mid-1990s, the following proton parameters are lower on average from 2009 through day 79 of 2013: solar wind speed and beta (∼11%), temperature (∼40%), thermal pressure (∼55%), mass flux (∼34%), momentum flux or dynamic pressure (∼41%), energy flux (∼48%), IMF magnitude (∼31%), and radial component of the IMF (∼38%). These results have important implications for the solar wind's interaction with planetary magnetospheres and the heliosphere's interaction with the local interstellar medium, with the proton dynamic pressure remaining near the lowest values observed in the space age: ∼1.4 nPa, compared to ∼2.4 nPa typically observed from the mid-1970s through the mid-1990s. The combination of lower magnetic flux emergence from the Sun (carried out in the solar wind as the IMF) and associated low power in the solar wind points to the causal relationship between them. Our results indicate that the low solar wind output is driven by an internal trend in the Sun that is longer than the ∼11 yr solar cycle, and they suggest that this current weak solar maximum is driven by the same trend.

Solar building construction. Special edition of the journal 'Sonnenenergie'; Solares Bauen. Sonderheft der Sonnenenergie

Energy Technology Data Exchange (ETDEWEB)

Rust, A. (comp.)

2003-10-01

This special issue of October 2003 reviews solar architecture, planning, applications, technology, market and knowledge. Subjects: Falkenweg housing development; Q-Cells solar factory; Modehaus Zara building; Haus Westermayr McCready building; Federal Environmental Office building, Dessau; 'Haus im Himmel' building; NRW state representatives building in Berlin; Zero-emission building 'Sunny Woods', Zurich; Hellerau workshop buildings, Dresden; HOCHTIEF PRISMA Haus building, Frankfurt; Solar government buildings, Berlin; SOLARBAU programme; Energy supply concepts based on photovoltaic power supply; Solar cooling; Photovoltaic lamellas; Solar building construction; Solar contracting; Solar building modernisation; Integrated PV systems in Europe; Living in passive buildings; Funding programmes for renewable energy sources and building construction. (orig./AKF)

Solar thermal power plants

International Nuclear Information System (INIS)

Schnatbaum, L.

2009-01-01

The solar thermal power plant technology, the opportunities it presents and the developments in the market are outlined. The focus is on the technology of parabolic trough power plants, a proven technology for solar power generation on a large scale. In a parabolic trough power plant, trough-shaped mirrors concentrate the solar irradiation onto a pipe in the focal line of the collector. The thermal energy thus generated is used for electricity generation in a steam turbine. Parabolic trough plants can be combined with thermal storage and fossil or biomass fired heat exchangers to generate electricity even when the sun is not shining. Solar Millennium AG in Erlangen has developed the first power plant of this kind in Europe. After two years of construction the plant started operation in Southern Spain in 2008. This one and its sister projects are important steps leading the way for the whole market. The paper also covers the technological challenges, the key components used and the research and development activities concerning this technology. Solar thermal power plants are ideal for covering peak and medium loads in power grids. In hybrid operation they can also cover base-load. The Solar Chimney power plant, another striking technology for the conversion of solar into electric energy, is described briefly. The paper concludes with a look at the future - the import of solar energy from the deserts of North Africa to central Europe. (author)

Study of solar radiation prediction and modeling of relationships between solar radiation and meteorological variables

International Nuclear Information System (INIS)

Sun, Huaiwei; Zhao, Na; Zeng, Xiaofan; Yan, Dong

2015-01-01

Highlights: • We investigate relationships between solar radiation and meteorological variables. • A strong relationship exists between solar radiation and sunshine duration. • Daily global radiation can be estimated accurately with ARMAX–GARCH models. • MGARCH model was applied to investigate time-varying relationships. - Abstract: The traditional approaches that employ the correlations between solar radiation and other measured meteorological variables are commonly utilized in studies. It is important to investigate the time-varying relationships between meteorological variables and solar radiation to determine which variables have the strongest correlations with solar radiation. In this study, the nonlinear autoregressive moving average with exogenous variable–generalized autoregressive conditional heteroscedasticity (ARMAX–GARCH) and multivariate GARCH (MGARCH) time-series approaches were applied to investigate the associations between solar radiation and several meteorological variables. For these investigations, the long-term daily global solar radiation series measured at three stations from January 1, 2004 until December 31, 2007 were used in this study. Stronger relationships were observed to exist between global solar radiation and sunshine duration than between solar radiation and temperature difference. The results show that 82–88% of the temporal variations of the global solar radiation were captured by the sunshine-duration-based ARMAX–GARCH models and 55–68% of daily variations were captured by the temperature-difference-based ARMAX–GARCH models. The advantages of the ARMAX–GARCH models were also confirmed by comparison of Auto-Regressive and Moving Average (ARMA) and neutral network (ANN) models in the estimation of daily global solar radiation. The strong heteroscedastic persistency of the global solar radiation series was revealed by the AutoRegressive Conditional Heteroscedasticity (ARCH) and Generalized Auto

Solar energy engineering processes and systems

CERN Document Server

Kalogirou, Soteris A

2009-01-01

As perhaps the most promising of all the renewable energy sources available today, solar energy is becoming increasingly important in the drive to achieve energy independence and climate balance. This new book is the masterwork from world-renowned expert Dr. Soteris Kalogirou, who has championed solar energy for decades. The book includes all areas of solar energy engineering, from the fundamentals to the highest level of current research. The author includes pivotal subjects such as solar collectors, solar water heating, solar space heating and cooling, industrial process heat, solar desalina

Solar engineering 1995: Proceedings. Volume 1

International Nuclear Information System (INIS)

Stine, W.B.; Tanaka, Tadayoshi; Claridge, D.E.

1995-01-01

This is Volume 1 of the papers presented at the 1995 ASME/JSME/JSES International Solar Energy Conference. The topics of the papers include wind energy, heat pump performance, ground source and solar chemical heat pumps, analysis of measured building energy data, thermal storage, system modeling of buildings, evaluation of the Federal Building energy Efficiency program, sustainable projects, bioconversion, solar chemistry, solar detoxification innovative concepts and industrial applications, solar thermal power systems, DISH/engine power systems, power towers, solar thermal power advanced development, and solar thermal process heating and cooling

Solar energy engineering processes and systems

CERN Document Server

Kalogirou, Soteris A

2013-01-01

As perhaps the most promising of all the renewable energy sources available today, solar energy is becoming increasingly important in the drive to achieve energy independence and climate balance. This new book is the masterwork from world-renowned expert Dr. Soteris Kalogirou, who has championed solar energy for decades. The book includes all areas of solar energy engineering, from the fundamentals to the highest level of current research. The author includes pivotal subjects such as solar collectors, solar water heating, solar space heating and cooling, industrial process heat, solar desalina

Experiment Based Teaching of Solar Cell Operation and Characterization Using the SolarLab Platform

DEFF Research Database (Denmark)

Spataru, Sergiu; Sera, Dezso; Kerekes, Tamas

2014-01-01

interfaces for exploring different solar cell principles and topics. The exercises presented in the current paper have been adapted from the original exercises developed for the SolarLab platform and are currently included in the Photovoltaic Power Systems courses (MSc and PhD level) taught at the Department...... which is a laboratory teaching tool developed at Transylvania University of Brasov. Using this platform, solar cells can be characterized under various illumination, temperature and angle of light incidence. Additionally, the SolarLab platform includes guided exercises and intuitive graphical user......Experiment based teaching methods are a great way to get students involved and interested in almost any topic. This paper presents such a hands-on approach for teaching solar cell operation principles along with characterization and modelling methods. This is achieved with the SolarLab platform...

A comprehensive review on solar cookers

International Nuclear Information System (INIS)

Cuce, Erdem; Cuce, Pinar Mert

2013-01-01

In this paper, a thorough review of the available literature on solar cookers is presented. The review is performed in a thematic way in order to allow an easier comparison, discussion and evaluation of the findings obtained by researchers, especially on parameters affecting the performance of solar cookers. The review covers a historic overview of solar cooking technology, detailed description of various types of solar cookers, geometry parameters affecting performance of solar cookers such as booster mirrors, glazing, absorber plate, cooking pots, heat storage materials and insulation. Moreover, thermodynamic assessment of solar cooking systems and qualitative evaluation of thermal output offered by solar cookers are analyzed in detail. Complex designs of solar cookers/ovens with and without heat storage material are illustrated and furthermore possible methods to be able to enhance the power outputs of solar cooking systems are presented. Feasibility analysis, environmental impacts and future potential of solar cookers are also considered in the study.

Decrease of the solar flare/solar wind flux ratio in the past several aeons from solar neon and tracks in lunar soil plagioclases

International Nuclear Information System (INIS)

Wieler, R.; Etique, Ph.; Signer, P.; Poupeau, G.

1982-08-01

The He, Ne, and Ar concentrations and isotopic compositions of mineral separates of six lunar subsurface samples and of two regolith breccias which were exposed to the sun as early as 2 - 3 billion years ago are determined. The results are compared with our noble gas data obtained previously on mineral separates of lunar surface soil samples most of which contain recently implanted solar gases. The mean solar flare track densities were determined on aliquots of several of the plagioclase separates analyzed for noble gases. Solar wind retentive mafic minerals and ilmenites show that a possible secular increase of the 20 Ne/ 22 Ne ratio in the solar wind during the last 2 - 3 Ga. is 20 Ne/ 22 Ne of approximately 11.3 - 11.8, reported for solar flare Ne retained in plagioclase separates from lunar soils. The solar flare track data and the Ne data independently show that plagioclases exposed to the sun over the last 10 8 years recorded a lower mean ratio of solar flare to solar wind intensities than samples exposed about 1 - 3 billion years ago. On the basis of track data these ratios are estimated to differ by a factor approximately 2. (Author) [pt

Experimental Study on Various Solar Still Designs

OpenAIRE

T. Arunkumar; K. Vinothkumar; Amimul Ahsan; R. Jayaprakash; Sanjay Kumar

2012-01-01

Humankind has depended for ages on underground water reservoirs for its fresh water needs. But these sources do not always prove to be useful due to the presence of excessive salinity in the water. In this paper, the fabrication of seven solar still designs such as spherical solar still, pyramid solar still, hemispherical solar still, double basin glass solar still, concentrator coupled single slope solar still, tubular solar still and tubular solar still coupled with pyramid solar still and ...

The inconstant solar constant