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Sample records for suntec slats solar

  1. Optical analysis of a curved-slats fixed-mirror solar concentrator by a forward ray-tracing procedure.

    Science.gov (United States)

    Pujol Nadal, Ramon; Martínez Moll, Víctor

    2013-10-20

    Fixed-mirror solar concentrators (FMSCs) use a static reflector and a moving receiver. They are easily installable on building roofs. However, for high-concentration factors, several flat mirrors would be needed. If curved mirrors are used instead, high-concentration levels can be achieved, and such a solar concentrator is called a curved-slats fixed-mirror solar concentrator (CSFMSC), on which little information is available. Herein, a methodology is proposed to characterize the CSFMSC using 3D ray-tracing tools. The CSFMSC shows better optical characteristics than the FMSC, as it needs fewer reflector segments for achieving the same concentration and optical efficiency.

  2. Slat Heater Boxes for Thermal Vacuum Testing

    Science.gov (United States)

    Ungar, Eugene

    2003-01-01

    Slat heater boxes have been invented for controlling the sink temperatures of objects under test in a thermal vacuum chamber, the walls of which are cooled to the temperature of liquid nitrogen. A slat heater box (see Figure 1) includes a framework of struts that support electrically heated slats that are coated with a high-emissivity optically gray paint. The slats can be grouped together into heater zones for the purpose of maintaining an even temperature within each side. The sink temperature of an object under test is defined as the steady-state temperature of the object in the vacuum/ radiative environment during the absence of any internal heat source or sink. The slat heater box makes it possible to closely control the radiation environment to obtain a desired sink temperature. The slat heater box is placed inside the cold thermal vacuum chamber, and the object under test is placed inside (but not in contact with) the slat heater box. The slat heaters occupy about a third of the field of view from any point on the surface of the object under test, the remainder of the field of view being occupied by the cold chamber wall. Thus, the radiation environment is established by the combined effects of the slat heater box and the cold chamber wall. Given (1) the temperature of the chamber wall, (2) the fractions of the field of view occupied by the chamber wall and the slat heater box, and (3) the emissivities of the slats, chamber wall, and the surface of object under test, the slat temperature required to maintain a desired sink temperature can be calculated by solving the equations of gray-body radiation for the steady-state adiabatic case (equal absorption and emission by the object under test). Slat heater boxes offer an important advantage over the infrared lamps that have been previously used to obtain desired sink temperatures: In comparison with an infrared lamp, a slat heater box provides a greater degree of sink temperature uniformity for a test

  3. ENVIRONMENTAL TECHNOLOGY VERIFICATION: JOINT (NSF-EPA) VERIFICATION STATEMENT AND REPORT FOR THE UV DISINFECTION OF SECONDARY EFFLUENTS, SUNTEC, INC. MODEL LPX200 DISINFECTION SYSTEM - 03/09/WQPC-SWP

    Science.gov (United States)

    Verification testing of the SUNTEC LPX200 UV Disinfection System to develop the UV delivered dose flow relationship was conducted at the Parsippany-Troy Hills wastewater treatment plant test site in Parsippany, New Jersey. Two lamp modules were mounted parallel in a 6.5-meter lon...

  4. 14 CFR 25.701 - Flap and slat interconnection.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Flap and slat interconnection. 25.701....701 Flap and slat interconnection. (a) Unless the airplane has safe flight characteristics with the... sides of the plane of symmetry must be synchronized by a mechanical interconnection or...

  5. Rotor Performance Enhancement Using Slats on the Inner Part of a 10MW Rotor

    DEFF Research Database (Denmark)

    Gaunaa, Mac; Zahle, Frederik; Sørensen, Niels N.

    2013-01-01

    The present work continues the investigations of using slats on the inner parts of wind turbine rotors by using an updated version of the 2D CFD based airfoil/slat design tool earlier used by the authors in combination with the rotor design methods from [8] to design slats for 0:1 > r=R > 0......, thus allowing for a much broader design space than in the previous works where only the position, size and additional camber of the slat airfoil could be adjusted. The aerodynamic performance of a slatted rotor is for the first time evaluated using 3D CFD in this work, and the results are compared...

  6. Rotor Performance Enhancement Using Slats on the Inner Part of a 10MW Rotor

    DEFF Research Database (Denmark)

    The present work continues the investigations of using slats on the inner parts of wind turbine rotors by using an updated version of the 2D CFD based airfoil/slat design tool earlier used by the authors in combination with the rotor design methods from [8] to design slats for 0:1 > r=R > 0......, thus allowing for a much broader design space than in the previous works where only the position, size and additional camber of the slat airfoil could be adjusted. The aerodynamic performance of a slatted rotor is for the first time evaluated using 3D CFD in this work, and the results are compared...

  7. Modelling of Air Flow trough a Slatted Floor by CFD

    DEFF Research Database (Denmark)

    Svidt, Kjeld; Bjerg, Bjarne; Morsing, Svend;

    In this paper two different CFD-approaches are investigated to model the airflow through a slatted floor. Experiments are carried out in a full-scale test room. The computer simulations are carried out with the CFD-code FLOVENT, which solves the time-averaged Navier-Stokes equations by use of the k...

  8. Effects of Geometric Details on Slat Noise Generation and Propagation

    Science.gov (United States)

    Khorrami, Mehdi R.; Lockard, David P.

    2009-01-01

    The relevance of geometric details to the generation and propagation of noise from leading-edge slats is considered. Typically, such details are omitted in computational simulations and model-scale experiments thereby creating ambiguities in comparisons with acoustic results from flight tests. The current study uses two-dimensional, computational simulations in conjunction with a Ffowcs Williams-Hawkings (FW-H) solver to investigate the effects of previously neglected slat "bulb" and "blade" seals on the local flow field and the associated acoustic radiation. The computations show that the presence of the "blade" seal at the cusp in the simulated geometry significantly changes the slat cove flow dynamics, reduces the amplitudes of the radiated sound, and to a lesser extent, alters the directivity beneath the airfoil. Furthermore, the computations suggest that a modest extension of the baseline "blade" seal further enhances the suppression of slat noise. As a side issue, the utility and equivalence of FW-H methodology for calculating far-field noise as opposed to a more direct approach is examined and demonstrated.

  9. The Influence of Realistic Reynolds Numbers on Slat Noise Simulations

    Science.gov (United States)

    Lockard, David P.; Choudhari, Meelan M.

    2012-01-01

    The slat noise from the 30P/30N high-lift system has been computed using a computational fluid dynamics code in conjunction with a Ffowcs Williams-Hawkings solver. Varying the Reynolds number from 1.71 to 12.0 million based on the stowed chord resulted in slight changes in the radiated noise. Tonal features in the spectra were robust and evident for all Reynolds numbers and even when a spanwise flow was imposed. The general trends observed in near-field fluctuations were also similar for all the different Reynolds numbers. Experiments on simplified, subscale high-lift systems have exhibited noticeable dependencies on the Reynolds number and tripping, although primarily for tonal features rather than the broadband portion of the spectra. Either the 30P/30N model behaves differently, or the computational model is unable to capture these effects. Hence, the results underscore the need for more detailed measurements of the slat cove flow.

  10. Reactions of dairy cows during the operation of a robotic slat cleaner

    Directory of Open Access Journals (Sweden)

    Anna Stülpner

    2014-10-01

    Full Text Available During manure removal, robotic slat cleaners move in close proximity to dairy cows. The present study investigated the influence of a robotic cleaner on the animals by video recording and analysing their reactions. As most important influence factors concerning individual animal reactions, the small proportion of 8 % of marked reactions by cows to the slat robot as well as the actual distance between the cows and the slat robot, indicated a good adaption of dairy cows to the equipment. Observation of the complete herd of cows demonstrated that animals increased their movement from lying area to feeding area while the robotic slat cleaner was operating.

  11. Characterization of Unsteady Flow Structures Near Leading-Edge Slat. Part 1; PIV Measurements

    Science.gov (United States)

    Jenkins, Luther N.; Khorrami, Mehdi R.; Choudhari, Meelan

    2004-01-01

    A comprehensive computational and experimental study has been performed at the NASA Langley Research Center as part of the Quiet Aircraft Technology (QAT) Program to investigate the unsteady flow near a leading-edge slat of a two-dimensional, high-lift system. This paper focuses on the experimental effort conducted in the NASA Langley Basic Aerodynamics Research Tunnel (BART) where Particle Image Velocimetry (PIV) data was acquired in the slat cove and at the slat trailing edge of a three-element, high-lift model at 4, 6, and 8 degrees angle of attack and a freestream Mach Number of 0.17. Instantaneous velocities obtained from PIV images are used to obtain mean and fluctuating components of velocity and vorticity. The data show the recirculation in the cove, reattachment of the shear layer on the slat lower surface, and discrete vortical structures within the shear layer emanating from the slat cusp and slat trailing edge. Detailed measurements are used to examine the shear layer formation at the slat cusp, vortex shedding at the slat trailing edge, and convection of vortical structures through the slat gap. Selected results are discussed and compared with unsteady, Reynolds-Averaged Navier-Stokes (URANS) computations for the same configuration in a companion paper by Khorrami, Choudhari, and Jenkins (2004). The experimental dataset provides essential flow-field information for the validation of near-field inputs to noise prediction tools.

  12. Influence of Spanwise Boundary Conditions on Slat Noise Simulations

    Science.gov (United States)

    Lockard, David P.; Choudhari, Meelan M.; Buning, Pieter G.

    2015-01-01

    The slat noise from the 30P/30N high-lift system is being investigated through computational fluid dynamics simulations with the OVERFLOW code in conjunction with a Ffowcs Williams-Hawkings acoustics solver. In the present study, two different spanwise grids are being used to investigate the effect of the spanwise extent and periodicity on the near-field unsteady structures and radiated noise. The baseline grid with periodic boundary conditions has a short span equal to 1/9th of the stowed chord, whereas the other, longer span grid adds stretched grids on both sides of the core, baseline grid to allow inviscid surface boundary conditions at both ends. The results indicate that the near-field mean statistics obtained using the two grids are similar to each other, as are the directivity and spectral shapes of the radiated noise. However, periodicity forces all acoustic waves with less than one wavelength across the span to be two-dimensional, without any variation in the span. The spanwise coherence of the acoustic waves is what is needed to make estimates of the noise that would be radiated from realistic span lengths. Simulations with periodic conditions need spans of at least six slat chords to allow spanwise variation in the low-frequencies associated with the peak of broadband slat noise. Even then, the full influence of the periodicity is unclear, so employing grids with a fine, central region and highly stretched meshes that go to slip walls may be a more efficient means of capturing the spanwise decorrelation of low-frequency acoustic phenomena.

  13. Oriënterende emissiemetingen aan de Comfort Slat Mats voor melkvee = Explorative emission measurements on Comfort Slat Mats for dairy cattle

    NARCIS (Netherlands)

    Dooren, van H.J.C.; Blanken, K.; Gunnink, H.

    2009-01-01

    Emissions of ammonia and methane from the comfort slat mats (a new floor type for dairy cattle) were measured with a dynamic box method. Emissions were reduced up to 50% for ammonia and for 75% for methane.

  14. Tomographic image quality of rotating slat versus parallel hole-collimated SPECT

    Science.gov (United States)

    Van Holen, Roel; Staelens, Steven; Vandenberghe, Stefaan

    2011-11-01

    Parallel and converging hole collimators are most frequently used in nuclear medicine. Less common is the use of rotating slat collimators for single photon emission computed tomography (SPECT). The higher photon collection efficiency, inherent to the geometry of rotating slat collimators, results in much lower noise in the data. However, plane integrals contain spatial information in only one direction, whereas line integrals provide two-dimensional information. It is not a trivial question whether the initial gain in efficiency will compensate for the lower information content in the plane integrals. Therefore, a comparison of the performance of parallel hole and rotating slat collimation is needed. This study compares SPECT with rotating slat and parallel hole collimation in combination with MLEM reconstruction with accurate system modeling and correction for scatter and attenuation. A contrast-to-noise study revealed an improvement of a factor 2-3 for hot lesions and more than a factor of 4 for cold lesion. Furthermore, a clinically relevant case of heart lesion detection is simulated for rotating slat and parallel hole collimators. In this case, rotating slat collimators outperform the traditional parallel hole collimators. We conclude that rotating slat collimators are a valuable alternative for parallel hole collimators.

  15. The Variation of Slat Noise with Mach and Reynolds Numbers

    Science.gov (United States)

    Lockhard, David P.; Choudhari, Meelan M.

    2011-01-01

    The slat noise from the 30P30N high-lift system has been computed using a computational fluid dynamics code in conjunction with a Ffowcs Williams-Hawkings solver. By varying the Mach number from 0.13 to 0.25, the noise was found to vary roughly with the 5th power of the speed. Slight changes in the behavior with directivity angle could easily account for the different speed dependencies reported in the literature. Varying the Reynolds number from 1.4 to 2.4 million resulted in almost no differences, and primarily served to demonstrate the repeatability of the results. However, changing the underlying hybrid Reynolds-averaged-Navier-Stokes/Large-Eddy-Simulation turbulence model significantly altered the mean flow because of changes in the flap separation. However, the general trends observed in both the acoustics and near-field fluctuations were similar for both models.

  16. The Effect of Cross Flow on Slat Noise

    Science.gov (United States)

    Lockard, David P.; Choudhari, Meelan M.

    2010-01-01

    This paper continues the computational examination (AIAA Journal, Vol. 45, No. 9, 2007, pp. 2174-2186) of the unsteady flow within the slat cove region of a multi-element high-lift airfoil configuration. Two simulations have been performed to examine the effect of cross flow on the near-field fluctuations and far-field acoustics. The cross flow was imposed by changing the free-stream velocity vector and modifying the Reynolds number. The cross flow does appear to alter the dynamics in the cove region, but the impact on the noise seems to be more dependent on the flow conditions. However, separating out the true effects of the cross flow from those of the Mach and Reynolds number would require additional calculations to isolate those effects.

  17. Changes in hoof health and animal hygiene in a dairy herd after covering concrete slatted floor with slatted rubber mats: a case study.

    Science.gov (United States)

    Ahrens, F; Platz, S; Link, C; Mahling, M; Meyer, H H D; Erhard, M H

    2011-05-01

    The objective was to investigate the effect of changing the flooring in the alleys of a barn from slatted concrete to slatted rubber mats on hoof disorders and animal hygiene in 44 loose-housed Brown Swiss dairy cows. Cows were examined for disorders of the hind hooves (hemorrhages, white line fissures, ulcers, heel horn erosion, and digital dermatitis) and for skin lesions. The dirtiness of the animals and of the floor was recorded. Climatic (temperature, humidity) and ammonia gas conditions were measured. Evaluations were carried out when the cows were housed on a concrete slatted floor and after 4 and 10 mo on soft flooring (slatted rubber mats, 29-mm thick). The anatomical portion of claw (medial, lateral), number of lactations (parity), and days in milk were included as covariates in the statistical model. Changing the flooring from slatted concrete to slatted rubber mats increased the score for white line fissures [1.0 ± 0.3 (concrete) vs. 2.5 ± 0.4 (10 mo rubber mats)] and influenced air humidity (i.e., the difference in the absolute humidity between the inside and outside of the barn increased from 1.5 ± 0.1 to 1.7 ± 0.2g/m(3)), whereas the other hoof disorders, skin lesions (score of 8.7 ± 0.3), the dirtiness of the animals (score of 5.9 ± 0.3), and the floor (score of 2.1 ± 0.1), and ammonia gas concentration (2.6 ± 0.3mg/kg) were not affected (overall scores or measures; mean ± SE). Lateral claws were more affected (except for heel horn erosion) than medial claws (estimated effects between 1.3 ± 0.2 and 3.0 ± 0.6). Parity influenced hoof disorders (except for hemorrhages) and skin lesions (estimated effects between -0.6 ± 0.3 and 0.5 ± 0.2). Days in milk influenced hoof disorders, but had no effect on skin lesions and on the dirtiness of the animal. Irrespective of floor type, the slots (2.6 ± 0.1) were dirtier than the slats (1.6 ± 0.1). In conclusion, covering slatted concrete flooring with slatted rubber mats partially impaired hoof

  18. Computational Modeling of a Mechanized Benchtop Apparatus for Leading-Edge Slat Noise Treatment Device Prototypes

    Science.gov (United States)

    Turner, Travis L.; Moore, James B.; Long, David L.

    2017-01-01

    Airframe noise is a growing concern in the vicinity of airports because of population growth and gains in engine noise reduction that have rendered the airframe an equal contributor during the approach and landing phases of flight for many transport aircraft. The leading-edge-slat device of a typical high-lift system for transport aircraft is a prominent source of airframe noise. Two technologies have significant potential for slat noise reduction; the slat-cove filler (SCF) and the slat-gap filler (SGF). Previous work was done on a 2D section of a transport-aircraft wing to demonstrate the implementation feasibility of these concepts. Benchtop hardware was developed in that work for qualitative parametric study. The benchtop models were mechanized for quantitative measurements of performance. Computational models of the mechanized benchtop apparatus for the SCF were developed and the performance of the system for five different SCF assemblies is demonstrated.

  19. Development of a SMA-Based, Slat-Gap Filler for Airframe Noise Reduction

    Science.gov (United States)

    Turner, Travis L.; Long, David L.

    2015-01-01

    Noise produced by unsteady flow around aircraft structures, termed airframe noise, is an important source of aircraft noise during the approach and landing phases of flight. Conventional leading-edge-slat devices for high lift on typical transport aircraft are a prominent source of airframe noise. Many concepts for slat noise reduction have been investigated. Slat-cove fillers have emerged as an attractive solution, but they maintain the gap flow, leaving some noise production mechanisms unabated, and thus represent a nonoptimal solution. Drooped-leading-edge (DLE) concepts have been proposed as "optimal" because the gap flow is eliminated. The deployed leading edge device is not distinct and separate from the main wing in DLE concepts and the high-lift performance suffers at high angles of attack (alpha) as a consequence. Elusive high-alpha performance and excessive weight penalty have stymied DLE development. The fact that high-lift performance of DLE systems is only affected at high alpha suggests another concept that simultaneously achieves the high-lift of the baseline airfoil and the noise reduction of DLE concepts. The concept involves utilizing a conventional leading-edge slat device and a deformable structure that is deployed from the leading edge of the main wing and closes the gap between the slat and main wing, termed a slat-gap filler (SGF). The deployable structure consists of a portion of the skin of the main wing and it is driven in conjunction with the slat during deployment and retraction. Benchtop models have been developed to assess the feasibility and to study important parameters. Computational models have assisted in the bench-top model design and provided valuable insight in the parameter space as well as the feasibility.

  20. Aerodynamic Impact of an Aft-Facing Slat-Step on High Re Airfoils

    Science.gov (United States)

    Kibble, Geoffrey; Petrin, Chris; Jacob, Jamey; Elbing, Brian; Ireland, Peter; Black, Buddy

    2016-11-01

    Typically, the initial aerodynamic design and subsequent testing and simulation of an aircraft wing assumes an ideal wing surface without imperfections. In reality, however the surface of an in-service aircraft wing rarely matches the surface characteristics of the test wings used during the conceptual design phase and certification process. This disconnect is usually deemed negligible or overlooked entirely. Specifically, many aircraft incorporate a leading edge slat; however, the mating between the slat and the top surface of the wing is not perfectly flush and creates a small aft-facing step behind the slat. In some cases, the slat can create a step as large as one millimeter tall, which is entirely submerged within the boundary layer. This abrupt change in geometry creates a span-wise vortex behind the step and in transonic flow causes a shock to form near the leading edge. This study investigates both experimentally and computationally the implications of an aft-facing slat-step on an aircraft wing and is compared to the ideal wing surface for subsonic and transonic flow conditions. The results of this study are useful for design of flow control modifications for aircraft currently in service and important for improving the next generation of aircraft wings.

  1. Slat Noise Predictions Using Higher-Order Finite-Difference Methods on Overset Grids

    Science.gov (United States)

    Housman, Jeffrey A.; Kiris, Cetin

    2016-01-01

    Computational aeroacoustic simulations using the structured overset grid approach and higher-order finite difference methods within the Launch Ascent and Vehicle Aerodynamics (LAVA) solver framework are presented for slat noise predictions. The simulations are part of a collaborative study comparing noise generation mechanisms between a conventional slat and a Krueger leading edge flap. Simulation results are compared with experimental data acquired during an aeroacoustic test in the NASA Langley Quiet Flow Facility. Details of the structured overset grid, numerical discretization, and turbulence model are provided.

  2. Dynamic model for ammonia volatilization in housing with partially slatted floors, for fattening pigs

    NARCIS (Netherlands)

    Aarnink, A.J.A.; Elzing, A.

    1998-01-01

    A dynamic model was developed to simulate the ammonia volatilization from pig housing with partially slatted floors, where no litter is used. Simulated ammonia emission levels were compared with measured levels for 1 day in each 3-week period during two fattening periods of 15 weeks (one in winter a

  3. Effect of two trimming methods of dairy cattle on concrete or rubber-covered slatted floors

    NARCIS (Netherlands)

    Ouweltjes, W.; Holzhauer, M.; Tol, van der P.P.J.; Werf, van der J.T.N.

    2009-01-01

    This study monitored claw health, claw conformation, locomotion, activity, and step traits of cows from a single dairy herd that were trimmed according to the standard Dutch method or with an alternative "concave" trimming method. Half of the cows were kept in a stall section with concrete slatted f

  4. A Comparison of the Noise Characteristics of a Conventional Slat and Krueger Flap

    Science.gov (United States)

    Bahr, Christopher J.; Hutcheson, Florence V.; Thomas, Russell H.; Housman, Jeffery A.

    2016-01-01

    An aeroacoustic test of two types of leading-edge high-lift devices has been conducted in the NASA Langley Quiet Flow Facility. The test compares a conventional slat with a notional equivalent-mission Krueger flap. The test matrix includes points that allow for direct comparison of the conventional and Krueger devices for equivalent-mission configurations, where the two high-lift devices satisfy the same lift requirements for a free air flight path at the same cruise airfoil angle of attack. Measurements are made for multiple Mach numbers and directivity angles. Results indicate that the Krueger flap shows similar agreement to the expected power law scaling of a conventional flap, both in terms of Strouhal number and fixed frequency (as a surrogate for Helmholtz number). Directivity patterns vary depending on the specific slat and Krueger orientations. Varying the slat gap while holding overlap constant has the same influence on both the conventional slat and Krueger flap acoustic signature. Closing the gap shows dramatic reduction in levels for both devices. Varying the Krueger overlap has a different effect on the data when compared to varying the slat overlap, but analysis is limited by acoustic sources that regularly present themselves in model-scale wind tunnel testing but are not present for full-scale vehicles. The Krueger cavity is found to have some influence on level and directivity, though not as much as the other considered parameter variations. Overall, while the spectra of the two devices are different in detail, their scaling behavior for varying parameters is extremely similar.

  5. Analysis-Driven Design Optimization of a SMA-Based Slat-Cove Filler for Aeroacoustic Noise Reduction

    Science.gov (United States)

    Scholten, William; Hartl, Darren; Turner, Travis

    2013-01-01

    Airframe noise is a significant component of environmental noise in the vicinity of airports. The noise associated with the leading-edge slat of typical transport aircraft is a prominent source of airframe noise. Previous work suggests that a slat-cove filler (SCF) may be an effective noise treatment. Hence, development and optimization of a practical slat-cove-filler structure is a priority. The objectives of this work are to optimize the design of a functioning SCF which incorporates superelastic shape memory alloy (SMA) materials as flexures that permit the deformations involved in the configuration change. The goal of the optimization is to minimize the actuation force needed to retract the slat-SCF assembly while satisfying constraints on the maximum SMA stress and on the SCF deflection under static aerodynamic pressure loads, while also satisfying the condition that the SCF self-deploy during slat extension. A finite element analysis model based on a physical bench-top model is created in Abaqus such that automated iterative analysis of the design could be performed. In order to achieve an optimized design, several design variables associated with the current SCF configuration are considered, such as the thicknesses of SMA flexures and the dimensions of various components, SMA and conventional. Designs of experiment (DOE) are performed to investigate structural response to an aerodynamic pressure load and to slat retraction and deployment. DOE results are then used to inform the optimization process, which determines a design minimizing actuator forces while satisfying the required constraints.

  6. An assessment of a partial pit ventilation system to reduce emission under slatted floor

    DEFF Research Database (Denmark)

    Wu, Wentao; Zhang, Guoqiang; Bjerg, Bjarne Schmidt;

    2012-01-01

    CFD simulations were carried out to assess the feasibility of using RANS (Reynolds – averaged Navier– Stokes) turbulence models to evaluate the performance of a partial pit ventilation system to reduce gas emission under slatted floor. The entire system included a pit model with slatted floor...... and pit exhaust system, a wind table to simulate ground and a wind tunnel to simulate room space of a naturally ventilated livestock house. CFD simulations started with the selection of a proper domain. Two domains were chosen to evaluate the effect of domain simplification. The results showed...... that the effect was significant. The assessment of different turbulence models including the standard, RNG, realizable k _ e models; transition SST k _ x model; Reynolds Stress Models were conducted. Results of RSM were found out to agree best with measured results. In order to understand the transportation...

  7. What happens with cow behavior when replacing concrete slatted floor by rubber coating: a case study.

    Science.gov (United States)

    Platz, S; Ahrens, F; Bendel, J; Meyer, H H D; Erhard, M H

    2008-03-01

    An enhanced productive life cycle and improved animal welfare are aims pursued in dairy husbandry. This study assesses experimental observations on floor-associated behavior during the stepwise replacement of concrete slatted flooring by rubber mats. For this purpose, estrus (mounting) and hygiene behavior (licking while standing on 3 legs and caudal licking) within a herd of 50 loose-housed Brown Swiss dairy cows were analyzed by video observation before and after floor reconstruction. Still photographs and pedometers were used to asses step length and number of steps, representing walking behavior. Compared with the concrete floor surface, rubber coating led to an increase in step length (58 +/- 1 vs. 70 +/- 1 cm; n = 35) and in steps per day (4,226 +/- 450 vs. 5,611 +/- 495; mean +/- SEM; n = 9). Mounting was higher on the flooring covered with rubber mats (23 vs. 112). Collapsing or slipping during mounting only occurred on concrete slatted flooring (in 19 out of 23 mounting actions). Licking while standing on 3 legs and caudal licking increased up to 4-fold (105 vs. 511 observations). In conclusion, improvements were found in behavior when rubber-coated slatted floor surfaces were used in dairy cattle housing in transition from concrete flooring. Disorders in estrus and hygiene behavior were associated with the flooring of the barn and were relatively easy to investigate within the framework of farm welfare assessments.

  8. SLAT/Def6 plays a critical role in the pathogenic process of experimental autoimmune uveitis (EAU).

    Science.gov (United States)

    Vistica, Barbara P; Shi, Guangpu; Nugent, Lindsey; Tan, Cuiyan; Altman, Amnon; Gery, Igal

    2012-01-01

    SWAP 70-like adaptor of T cells (SLAT; aka Def6) is a recently discovered guanine nucleotide exchange factor for Rho guanosine triphosphate (GTP)ases that has been previously shown to play a role in cluster of differentiation(CD)4+ T cell activation, T-helper (Th)1/Th2/Th17 differentiation and development of experimental autoimmune encephalomyelitis. Here, we investigated the role of SLAT/Def6 in the development of experimental autoimmune uveitis (EAU), an animal model for several uveitic conditions in humans. SLAT/Def6 deficient ("KO") mice and C57BL/6 controls were immunized with interphotoreceptor retinoid-binding protein (IRBP), along with pertussis toxin. The development of ocular inflammation was determined by both fundoscopy and histological examination. Lymphoid cells from draining lymph nodes were cultured with IRBP to measure lymphocyte proliferation and release of cytokines. Purified dendritic cells were tested for their capacity to present antigen to responding lymphocytes. In addition, the lymphoid cells were tested for the expression of forkhead box P3 (FoxP3), using conventional methods, and the activity of T-regulatory cells was determined by their capacity to inhibit in vitro proliferative responses. Serum anti -IRBP antibody levels were measured by enzyme-linked immunosorbant assay (ELISA). quantitative polymerase chain reaction (qPCR) was used to determine the transcript levels of cytokines in inflamed eyes. SLAT/Def6 KO mice had significantly reduced EAU compared to controls. Cells isolated from draining lymph nodes of SLAT/Def6 KO mice exhibited impaired proliferation and production of Th1 and Th17 signature cytokines (interferon [IFN]-γ and interleukin [IL]-17, respectively) when compared with cells isolated from control mice. qPCR of inflamed eyes detected similar levels of IFN-γ transcript in control and SLAT/Def6 KO mice, whereas the IL-17 transcript levels in eyes of the SLAT/Def6 KO mice were lower than in eyes of the controls. The SLAT

  9. Longitudinal study of the effect of rubber slat mats on locomotory ability, body, limb and claw lesions, and dirtiness of group housed sows

    National Research Council Canada - National Science Library

    Calderón Díaz, J A; Fahey, A G; Kilbride, A L; Green, L E; Boyle, L A

    2013-01-01

    ...) slatted floor left uncovered or covered by 10-mm rubber slat mats (n = 80) through 2 parities. Lameness (0 = normal to 5 = severe), limb (0 = normal to 6 = severe) and body (0 = normal to 5 = severe) lesions, and manure on the body...

  10. Influence of plastic slatted floors compared with pine shaving litter on Pekin Duck condition during the summer months.

    Science.gov (United States)

    Fraley, S M; Fraley, G S; Karcher, D M; Makagon, M M; Lilburn, M S

    2013-07-01

    The management and well-being of commercial Pekin ducks has been studied in the European Union where straw is the predominant litter source. In the United States, however, the most prevalent litter is wood shavings, with a recent trend toward using plastic slatted flooring. A previous study in the United States evaluated the relationship between flooring type (litter, slats) and duck condition during winter months and found very few differences between the 2 in terms of overall duck condition. The purpose of the current study was to reevaluate the 2 flooring systems during the summer months to determine if seasonal differences would interact with flooring type to have an impact on duck condition. Eighteen commercial barns that produce Pekin ducks for Maple Leaf Farms Inc. (Leesburg, IN), located in northern Indiana and southern Wisconsin (n = 9 litter; n = 9 raised slatted floor), were used for this study. Twenty ducks were randomly selected from 5 predetermined areas within each house (n = 100 total) and scored for eye condition, nostril and feather cleanliness, and feather and foot pad quality at 7, 21, and 32 d of age. Environmental data, including carbon monoxide, ammonia, RH, and temperature, were also obtained at each collection day. The only statistical differences in body condition occurred at 7 d; there were more ducks with clear eyes and eye rings on the litter flooring, whereas average nostril scores were better on the plastic slatted floors. Live weight, weight gain per day, flock mortality, and condemnations at the plant were collected, and the only statistical difference was a higher gain per day for ducks reared on slatted floors compared with litter (P < 0.05). There were no differences between flooring systems in the environmental parameters measured within the barns. In summary, there were very few differences between the litter and slatted flooring systems, indicating that there may not be clear advantages for one particular flooring system over

  11. Determination of optimal collimation parameters for a rotating slat collimator system: a system matrix method using ML-EM

    Science.gov (United States)

    Boisson, F.; Bekaert, V.; Brasse, D.

    2016-03-01

    Nowadays, Single Photon imaging has become an essential part of molecular imaging and nuclear medicine. Whether to establish a diagnosis or in the therapeutic monitoring, this modality presents performance that continues to improve. For over 50 years, several collimators have been proposed. Mainly governed by collimation parameters, the resolution-sensitivity trade-off is the factor determining the collimator the most suitable for an intended study. One alternative to the common approaches is the rotating slat collimator (RSC). In the present study, we are aiming at developing a preclinical system equipped with a RSC dedicated to mice and rats imaging, which requires both high sensitivity and spatial resolution. We investigated the resolution-sensitivity trade-offs obtained by varying different collimation parameters: (i) the slats height (H), and (ii) the gap between two consecutive slats (g), considering different intrinsic spatial resolutions. One system matrix was generated for each set of collimation parameters (H,g). Spatial resolutions, Signal-to-Noise Ratio (SNR) and sensitivity obtained for all the set of collimation parameters (H,g) were measured in the 2D projections reconstructed with ML-EM. According to our results, 20 mm high slats and a 1 mm gap were chosen as a good RSC candidate for a preclinical detection module. This collimator will ensure a sensitivity greater than 0.2% and a system spatial resolution below 1 mm, considering an intrinsic spatial resolution below 0.8 mm.

  12. Development of a SMA-Based Slat-Cove Filler for Reduction of Aeroacoustic Noise Associated With Transport-Class Aircraft Wings

    Science.gov (United States)

    Turner, Travis L.; Kidd, Reggie T.; Hartl, Darren J.; Scholten, William D.

    2013-01-01

    Airframe noise is a significant part of the overall noise produced by typical, transport-class aircraft during the approach and landing phases of flight. Leading-edge slat noise is a prominent source of airframe noise. The concept of a slat-cove filler was proposed in previous work as an effective means of mitigating slat noise. Bench-top models were deployed at 75% scale to study the feasibility of producing a functioning slat-cove filler. Initial results from several concepts led to a more-focused effort investigating a deformable structure based upon pseudoelastic SMA materials. The structure stows in the cavity between the slat and main wing during cruise and deploys simultaneously with the slat to guide the aerodynamic flow suitably for low noise. A qualitative parametric study of SMA-enabled, slat-cove filler designs was performed on the bench-top. Computational models were developed and analyses were performed to assess the displacement response under representative aerodynamic load. The bench-top and computational results provide significant insight into design trades and an optimal design.

  13. Effect of concrete slats, three mat types and out-wintering pads on performance and welfare of finishing beef steers.

    Science.gov (United States)

    Earley, Bernadette; McNamara, John D; Jerrams, Stephen J; O'Riordan, Edward G

    2017-05-30

    The objective was to investigate the effect of placing mats on concrete slatted floors on performance, behaviour, hoof condition, dirt scores, physiological and immunological variables of beef steers, and to compare responses with animals on out-wintering pads. Continental crossbred beef steers [n = 360; mean (±SD) initial live weight 539 kg (42.2)] were blocked by breed and live weight and randomly assigned to one of five treatments; (1) Concrete slats alone, (2) Mat 1 (Natural Rubber structure) (Durapak Rubber Products), (3) Mat 2 (Natural rubber structure) (EasyFix), (4) Mat 3 (modified ethylene vinyl acetate (EVA) foam structure) and (5) Out-wintering pads (OWP's). Animals on the OWPs had a greater (P  0.05) as the other treatments. Animals on the OWPs had reduced lying percentage time compared with all the other treatments. Dry matter (DM) intake was greater for animals on the OWPs compared with all the other treatments. Carcass weight, kill out proportion, carcass fat score, carcass composition score, FCR and physiological responses were similar (P > 0.05) among treatments. No incidence of laminitis was observed among treatments. The number of hoof lesions was greater on all mat types (P concrete slats and OWP treatments. Dirt scores were greater (P concrete slats were disadvantaged in respect of animal welfare compared with animals housed on other floor types. It is concluded that the welfare of steers was not adversely affected by slats compared with different mat types or OWPs.

  14. Deskstudie naar de potentiële verlaging van de methaanemissie bij het comfort slat mats systeem en het balansballen systeem voor rundveestallen = Desk study regarding the lowered methane emission from animal houses using either the comfort slat mat or balance ball system for cattle houses

    NARCIS (Netherlands)

    Starmans, D.A.J.; Melse, R.W.

    2010-01-01

    Het comfort slat mats systeem en het balansballen systeem voor rundveestallen hebben als doel ammoniakemissiebeperking te bereiken in een rundveestal. Methaanmetingen wijzen uit dat zowel de toepassing van het balansballen- als het Comfort Slat Mats-systeem een verlaging van de emissie tot gevolg li

  15. Estimation of the prevalence of Salmonella species on the slatted area compared to the scratch area of broiler breeder chicken houses.

    Science.gov (United States)

    Behnke, Elena L; Hofacre, Charles L; Berghaus, Roy D

    2013-09-01

    With the objective of detecting Salmonella species in the poultry house environment, sampling broiler breeder houses in the two-thirds slatted area and the one-third scratch area with pine shavings bedding can be difficult. The slatted area is where the females, consisting of approximately 90% of the population, eat, drink, and spend the majority of their time. The scratch area is where the males eat and drink, as well as where mating and mortality occur. Besides the nest boxes, the female feeders and water lines make the slatted areas more difficult to sample. However, it is important to take samples from the area with the greatest likelihood of isolating Salmonella. Therefore, boot swab samples were collected from 21 commercial broiler breeder chicken houses representing three different companies in north Georgia to estimate the prevalence of Salmonella on the slat vs. the scratch area in each chicken house. Every house sampled had a central scratch area covered with litter and two elevated slat areas constructed of wood. Four boot swab samples were collected on each side slat area by walking the entire length of the house for each swab. Eight samples were collected in the same manner from the scratch area. Results of 335 total samples were acquired, 167 of which were obtained from the slat area and 168 of which came from the scratch area, yielding 242 total Salmonella isolations. Salmonella was found in 117 of the slat samples, representing 70.1%, compared to 125 of the scratch area samples, representing 74.4%. Both the univariate (P = 0.311) and the multivariable (P = 0.303) analysis showed that sampling location was not associated with Salmonella prevalence.

  16. Effects of two trimming methods of dairy cattle on concrete or rubber-covered slatted floors.

    Science.gov (United States)

    Ouweltjes, W; Holzhauer, M; van der Tol, P P J; van der Werf, J

    2009-03-01

    This study monitored claw health, claw conformation, locomotion, activity, and step traits of cows from a single dairy herd that were trimmed according to the standard Dutch method or with an alternative "concave" trimming method. Half of the cows were kept in a stall section with concrete slatted floors in the alleys. The other cows were kept in a pen within the same housing with an identical concrete slatted floor in the alleys, but with a rubber top layer. All experimental cows were kept in the same environment for at least 3 mo before and after trimming. It was hypothesized that trimming for more-concave soles (i.e., with 3 to 5 mm of sole dug out under the claw bone) was preferred to the standard Dutch trimming with flat sole surfaces for cows kept in stalls with soft alley floors. None of the claw health or locomotion traits differed for the trimming methods. No interactions were found between flooring and trimming method. Floor effects were significant for several traits. Cows on the rubber-topped floors had significantly fewer sole hemorrhages (prevalence of 22 vs. 48% in mo 3) and larger claws (claw length 76.1 +/- 5.0 vs. 72.5 +/- 4.9 mm; heel height 49.3 +/- 6.3 vs. 46.0 +/- 6.4 mm; claw diagonal 129 +/- 6.4 vs. 125 +/- 6.9 mm), spent more time standing in the alleys (55.4 +/- 2.8 vs. 49.6 +/- 2.8%), and had higher activity (61.0 +/- 3.7 vs. 53.0 +/- 3.7 steps/h). This suggests greater claw comfort on rubber flooring compared with concrete flooring. Kinetic patterns during claw-floor contact while walking were similar for all treatments. During the double-support (stance) phase, claw-floor contact area increased to a maximum in the first 30% of double-support phase time, remained more or less stable until 80% of double-support phase time, and sharply decreased as the animal pushed off as shown by the change in center of pressure. A gradual change of center of pressure in the medial direction during double-support phase time was shown. The research

  17. Locomotion and claw disorders in Norwegian dairy cows housed in freestalls with slatted concrete, solid concrete, or solid rubber flooring in the alleys.

    Science.gov (United States)

    Fjeldaas, T; Sogstad, A M; Osterås, O

    2011-03-01

    This study was part of a cross-sectional project on freestall housing, and the aim was to compare locomotion and claw disorders in freestall dairy cattle herds with slatted concrete, solid concrete, or solid rubber flooring in the alleys. The final population for studying claw disorders consisted of 66 dairy herds with 2,709 dry or lactating cows, whereas the population for studying locomotion consisted of 54 herds with 2,216 cows. All herds used Norwegian Red as the main breed. The herds were visited by 15 trained claw trimmers one time during the period from the beginning of February to summer let-out onto pasture in 2008. The trimmers assessed locomotion scores (LocS) of all cows before trimming. At trimming, claw disorders were diagnosed and recorded in the Norwegian Claw Health Card. Estimates describing locomotion and claw disorders in the hind feet were identified by use of multivariable models fit with LocS and each claw disorder as dependent variables, respectively. Herd nested within claw trimmer was included in the model as random effects. The odds ratio (OR) of having LocS >2 and LocS >3 was 1.9 and 2.1, respectively, on slatted concrete compared with solid concrete. Fewer cases of dermatitis were found on slatted than solid concrete (OR=0.70) and a tendency was observed for fewer heel horn erosions on slatted concrete than solid rubber (OR=0.47). Hemorrhages of the white line and sole were more prevalent in herds housed on slatted and solid concrete than in those housed on solid rubber (OR=2.6 and OR=2.1, respectively). White line fissures were also more prevalent in herds housed on slatted and solid concrete than in those housed on solid rubber (OR=2.1 and OR=2.0, respectively). Double soles were more prevalent on solid concrete than solid rubber (OR=4.4). However, sole ulcers were less prevalent in herds with slatted and solid concrete than solid rubber (OR=0.39 and OR=0.53, respectively). Fewer corkscrewed claws were found on slatted concrete than

  18. Postural behaviour in gilts housed on concrete and rubber slats during four seasons

    Directory of Open Access Journals (Sweden)

    Željko Pavičić

    2014-10-01

    Full Text Available In the present study, postural behaviour was compared between gilts kept in service unit with different types of flooring during all seasons. The study included four 28-day production cycles and 10 gilts per cycle, equally divided into a control and an experimental group. Control gilts were housed in gestation stalls with slatted concrete floor, whereas in the experimental group the floor was covered with an adjusted rubber mat. Postural behaviour of gilts was observed 4 times per cycle for 4 hours. Study results showed that during cooler seasons, gilts in concrete stalls spent more time standing and lying sternally, whereas gilts in matted stalls were mostly lying, predominantly laterally (P<0.001 all. There were no significant between group differences according to the time the gilts spent sitting or the frequency of changing posture in any season observed. Nevertheless, experimental animals spent significantly less time changing standing to both lying positions during all seasons (P<0.01 all. In conclusion, rubber mats may improve lying comfort in gilts; however, when using rubber mats, the house thermal conditions should be taken in consideration.

  19. 襟缝翼对民用飞机失速特性的影响%Effect of Slat and Flap on Stall Characteristic of Civil Aircraft

    Institute of Scientific and Technical Information of China (English)

    周涛; 李亚林; 梁益华; 陈迎春

    2012-01-01

    To detect factors of affecting stall characteristic and stability of aircraft, slot parameter of out board slat, separation face of inboard slat and fuselage, slot between slat and pylon, and slot parameter of flap were investigated. The results indicate that, root and tip of slat may affect pitching moment character- istic, slot between slat and pylon may improve lift coefficient, but no contribution for pitching moment characteristic, and, adjusting deploy angle of flap may not improve separation characteristic on main wing, because effective camber of wing is not changed.%从外侧缝翼缝道参数、内侧缝翼分离面、缝翼与挂架间隙以及后缘襟翼缝道参数等方面考虑,分析了民用飞机失速特性和失稳特性的影响因素.结果表明,前缘缝翼根部和梢部细节对力矩特性有较大影响,缝翼挂架堵缝可提高升力,不影响力矩特性,调整襟翼偏角,可改变机翼有效弯度,不改变主翼分离特性.

  20. Gaseous emissions during the fattening of pigs kept either on fully slatted floors or on straw flow.

    Science.gov (United States)

    Philippe, F-X; Laitat, M; Canart, B; Vandenheede, M; Nicks, B

    2007-11-01

    The aim of this study was to compare the environmental impact of the straw-flow system for fattening pigs with the slatted-floor system by measuring pollutant gas emissions such as ammonia (NH3), nitrous oxide (N2O), methane (CH4) and carbon dioxide (CO2), manure nitrogen (N) content and emissions of water vapour (H2O). Three successive batches of 32 pigs were fattened. For each batch, pigs were allotted to two groups raised in separated rooms fitted either with a concrete totally slatted-floor system (0.75 m2 per pig) or with a straw-flow system (0.79 m2 per pig). With this last system, pigs were kept on a sloped floor, straw being provided daily at the top of the pen. Throughout the fattening period, about 34.4 kg of straw were supplied per pig. The straw, mixed with dung, travelled down the slope by pig motion and went out of the pen to a scraped passage. The solid fraction was scraped every day, stored in a heap in the room and removed every month, 1 week before each period of gaseous emission measurement. The liquid fraction was automatically pumped from the scraped passage into a hermetic tank, which was emptied at the end of each fattening period. Rooms were ventilated mechanically in order to maintain a constant ambient temperature. Once a month, the emissions of NH3, N2O, CH4, CO2 and H2O were measured hourly for 6 consecutive days via infrared photoacoustic detection. Mean daily emissions per pig fattened on the slatted floor or on the sloped floor were, respectively, 4.98 and 13.31 g NH3, 0.67 and 0.68 g N2O, 15.2 and 8.88 g CH4, 548 g and 406 g CO2 equivalents, 1.61 and 1.77 kg CO2 and 2.33 and 2.95 kg H2O. Except for N2O emissions, all the differences were statistically significant (P straw-flow system, solid manure amounted on average to 209 kg per pig and liquid manure to 53 kg per pig. The total N-content of the manure was 2.23 kg N per pig with the straw-flow system (solid and liquid manure) v. 3.26 kg N per pig for slurry from the slatted

  1. Research of the effect of saw blade set dullness on the dimensions of longitudinally cut fir and spruce slats

    Directory of Open Access Journals (Sweden)

    Svrzić Uroš

    2012-01-01

    Full Text Available This paper analyzes the problem of choosing the best way of operating and maintaining a set of circular saws intended for longitudinal processing. The study objective was the analysis of current procedures of tools usage and recommendations for their improvement, in order to achieve better quality and longer operating life of tools. The tested set (24+5 blades was mounted on multisaw blade machine which produces slats from fir or spruce planks for three-layer parquet. Changes in thickness of sawed slats, operation time between two sharpenings and blade size changes after removing saw blades from machine and aftesharpening, were monitored. Control x-charts were used for stability evaluation. Work quality of saw blade set for longitudinal cut of fir and spruce planks was presented by cost-effectiveness ratio, ratio of total costs (for purchase of set and its servicing and volume of sawed timber. The saw blade set did not reach the targeted coefficient based on the previous tests. After each sharpening, the set had a different persistence presented in time, and we could not determine the work dynamics. The persistence of saw blade set was affected by wood resin that accumulates on the saw blade surface, the method and angles of sharpening, work dynamics and the continuity of cutting.

  2. Experimental study of the effect of a slat angle on double-element airfoil and application in vertical axis wind turbine

    DEFF Research Database (Denmark)

    Chougule, Prasad; Rosendahl, Lasse; Nielsen, Søren R.K.

    2015-01-01

    A design of double-element airfoil is proposed for its use in the vertical axis wind turbine. The double-element airfoil system consists of a main airfoil and a slat airfoil. The design parameters of the double-element airfoil system are given by the position and orientation of the trailing edge ...

  3. Synthetic rubber surface as an alternative to concrete to improve welfare and performance of finishing beef cattle reared on fully slatted flooring.

    Science.gov (United States)

    Brscic, M; Ricci, R; Prevedello, P; Lonardi, C; De Nardi, R; Contiero, B; Gottardo, F; Cozzi, G

    2015-08-01

    The aim of this study was to compare a fully slatted concrete floor (concrete slatted (CS)) with the same floor on which synthetic rubber slats were placed on the concrete slats (rubber slatted (RS)) as housing solution for finishing beef cattle. The present study involved five commercial beef cattle farms in which the floor of at least three pens was kept as fully slatted, and in an equal number of pens a rubber cover was placed on the floor, tightly matching the gap profile of the concrete slats to allow the drainage of manure. A total of 326 finishing beef bulls were used (153 on CS and 173 on RS), and regardless of the floor treatment animals were housed in groups of 6 to 12 bulls/pen with a space allowance of 3.1 ± 0.2 m2/bull. Bulls had similar initial live weights (422.3 kg on CS and 425.0 kg on RS), but bulls on RS were heavier at the end of the finishing period with a higher average daily gain than bulls kept on CS (1.53 v. 1.46 kg/day; PRubber covering prevented the occurrence of bursitis, but it increased the odds for hoof overgrowth at end of the finishing period. Hoof overgrowth detected in vivo in bulls on RS was confirmed at the slaughterhouse by the longer dorsal wall and diagonal lengths of the hoof as well as by a more acute toe angle. Compared with bulls on CS, bulls on RS showed less inactivity and resting time, increased social interactions, decreased abnormal lying down and unsuccessful attempts to lie down, as well as shortened the time for lying down. Bulls in RS pens were dirtier compared with those in CS pens, likely due to the draining gaps being reduced to 11.6 ± 1.2% of the total pen surface compared with the 16.9 ± 1.7% in CS pens. This study gave further evidence about the positive effects of the RS floor on growth performance and welfare of finishing beef cattle, although compromising cleanliness and hoof overgrowth.

  4. Longitudinal study of the effect of rubber slat mats on locomotory ability, body, limb and claw lesions, and dirtiness of group housed sows.

    Science.gov (United States)

    Calderón Díaz, J A; Fahey, A G; Kilbride, A L; Green, L E; Boyle, L A

    2013-08-01

    This study evaluated the influence of floor type on sow welfare with particular focus on lameness, claw lesions (CL), and injuries. The study used 164 gilts housed in groups of 8 from AI to 110 d of pregnancy in pens with concrete (n = 84) slatted floor left uncovered or covered by 10-mm rubber slat mats (n = 80) through 2 parities. Lameness (0 = normal to 5 = severe), limb (0 = normal to 6 = severe) and body (0 = normal to 5 = severe) lesions, and manure on the body (MOB; score 0 to 2) were recorded at AI, 24 to 72 h postmixing, between 50 and 70 d of pregnancy, and 2 wk before farrowing. Claw lesions (score 0 = normal to 3 = severe) were recorded at AI and between 50 and 70 d of pregnancy. The dirtiness and wetness of the floors was scored weekly (score 0 = clean to 4 = >75% of the pen soiled/wet). Data from the first and second parities were analyzed separately. Sows were categorized as nonlame (score ≤ 1) or lame (score ≥ 2). Median (M(e)) scores were calculated for CL and body and limb lesions and were classified as less than or equal to the median or greater than the median lesion scores. Sows on rubber slat mats had a reduced risk of lameness during both parities (P concrete. They also had an increased risk of scores greater than the median for toe overgrowth (M(e) = 2 and M(e) = 3 in the first and second parity, respectively) and heel sole crack (HSC; M(e) = 3) during both parities (P flooring type. There was also no association between body lesion score and flooring type. In this study, CL were not associated with an increased risk of lameness. Therefore, even though rubber slat mats were associated with an increased risk of CL, they improved the welfare of group housed sows by reducing the risk of lameness and limb lesions.

  5. Computational and Experimental Fluid-Structure Interaction Analysis of a High-Lift Wing with a Slat-Cove Filler for Noise Reduction

    Science.gov (United States)

    Scholten, William D.; Patterson, Ryan D.; Hartl, Darren J.; Strganac, Thomas W.; Chapelon, Quentin H. C.; Turner, Travis

    2017-01-01

    Airframe noise is a significant component of overall noise produced by transport aircraft during landing and approach (low speed maneuvers). A significant source for this noise is the cove of the leading-edge slat. The slat-cove filler (SCF) has been shown to be effective at mitigating slat noise. The objective of this work is to understand the fluid-structure interaction (FSI) behavior of a superelastic shape memory alloy (SMA) SCF in flow using both computational and physical models of a high-lift wing. Initial understanding of flow around the SCF and wing is obtained using computational fluid dynamics (CFD) analysis at various angles of attack. A framework compatible with an SMA constitutive model (implemented as a user material subroutine) is used to perform FSI analysis for multiple flow and configuration cases. A scaled physical model of the high-lift wing is constructed and tested in the Texas A&M 3 ft-by-4-foot wind tunnel. Initial validation of both CFD and FSI analysis is conducted by comparing lift, drag and pressure distributions with experimental results.

  6. Improving spatial resolution of high stopping power X- and gamma-ray cameras:. fibers or slat-structured detectors?

    Science.gov (United States)

    Gerstenmayer, J.-L.

    2000-11-01

    spread on the resolution. Technologies such as scintillator arrays (bundles), photoconductor plate piling, multi-hole- and multi-slat-solid detectors into gas chamber are employed. The first experimental results obtained at CEA are encouraging for applications such as high-energy low-dose fast imaging, flash radiography, radiotherapy positioning, nuclear waste or fuel survey, and, may be, high angular resolution imaging in the field of high-energy astrophysics. The relevance of "future" solutions is then examined, exhibiting theoretical and experimental frontiers: the most efficient structure for a future high-performance 2D integrating imager shall be a piling of thin metal layers, able to boost the quantum efficiency, sandwiched between a few hundreds of micrometers sensitive detectors as low-dark-current photoconductor (micro-strips) or parallel high-performance scintillating fiber sheets.

  7. NiTi SMA Wires Coupled with Kevlar Fabric: a Real Application of an Innovative Aircraft LE Slat System in SMAHC Material

    Science.gov (United States)

    Guida, M.; Marulo, F.; Russo, S.

    2017-08-01

    This paper investigates experimentally and numerically the response of a smart hybrid thermoplastic aircraft slat system subjected to a short-duration and high-frequency event like a birdstrike. The focus of the paper is to exploit the ability that superelastic shape memory alloys have to absorb and dissipate energy compared to conventional composite structures. The final objective of the work is to develop an innovative thermoplastic wing leading edge slat able to resist to an impact of 4-lb (1.8 kg) bird at speed of 350 kts (132 m/s), as requested by the aeronautical requirements. Aircraft leading edges must be certified for a proven level of bird impact resistance. In particular, the main structural requirement is to protect the torsion box and control devices from any significant damage caused by birdstrike in order to allow the aircraft to land safely. A clear increase of the composites toughness and higher absorbed energy levels before failure were also observed. This is due to the fact that SMA wires can absorb kinetic energy during the impact due to their remarkably large failure and recoverable strain and to their superelastic and hysteretic behaviour. The activities have been performed within the European Project COALESCE "Cost Efficient Advanced Leading Edge Structure", funded by the Seventh Framework Program Theme 7 Transport (incl. Aeronautics).

  8. 育肥猪舍用混凝土微缝地板的截面优化%Optimization of cross section of concrete narrow-gap slatted floor for fattening pig house

    Institute of Scientific and Technical Information of China (English)

    林玉涵; 陈刚; 施正香

    2013-01-01

      为解决现有混凝土微缝地板因截面设计不尽合理产生的承载力富余过大,导致实际生产中板体自重大、生产和运输成本高等问题.该文通过计算假定、截面和荷载转化的方法,对混凝土微缝地板的结构进行了理论剖析,对其制造材料、板体尺寸、配筋等进行了优化和力学性能计算.在截面面积减少3600 mm2、纵向钢筋面积减少213 mm2、混凝土的标号由 C30调至 C25的情况下,单块地板的正截面抗弯值为3.14 kN·m,斜截面抗剪值为3.56 kN,裂缝宽度值为0.167 mm,跨中截面挠度值为3.70 mm,均可满足育肥猪安全使用要求.优化后,单块地板混凝土使用量可节省0.01 m3,每平米地面铺设成本降低18%.%Aiming at solving problems of large own gravity and high transportation cost as well as the more needed bearing capacity of the concrete narrow-gap slatted floor caused by improperly design of the cross section, calculation hypothesis, conversion of cross section and load were carried out to analyze the structure of the concrete narrow-gap slatted floor in this study. It can be assumed that one fattening pig weights 100 kg on average and its four legs bear equal body weight. According to the dimension of the concrete narrow-gap slatted floor and fattening pigs, maximally, 10 pig legs can appear on one concrete narrow-gap slatted floor at the same time. The real cross section of the concrete narrow-gap slatted floor was changed into “T”cross section and 10 concentrated loads which were caused by legs were converted into continuous load in the calculation process. Based on the calculation results, it was concluded that the bearing capacity of the concrete narrow-gap slatted floor was larger than that needed. Therefore, optimization of materials, shape and dimension reinforcement of the narrow-gap slatted floor and mechanical calculation were done. After the optimization, for single narrow-gap slatted floor, the grade of the

  9. On the use of tensegrity structures for kinetic solar facades of smart buildings

    Science.gov (United States)

    Fraternali, F.; De Chiara, E.; Skelton, R. E.

    2015-10-01

    We investigate the use of tensegrity structures with morphing and prestress-stability capabilities for the design of active solar façades of smart buildings. Morphing tensegrity lattices are used to design shading screens composed of umbrella-shaped ‘eyes’ that are opened and closed by adjusting the elongation in a limited number of cables. Prestressable lattices are instead employed to design superstable Venetian blinds that are composed of orientable slats. Future use of tensegrity solutions for next-generation smart buildings are outlined, with the aim of designing kinetic solar façades that combine morphing abilities with prestress-stability.

  10. Low-speed aerodynamic performance of an aspect-ratio-10 supercritical-wing transport model equipped with a full-span slat and part-span and full-span double-slotted flaps

    Science.gov (United States)

    Morgan, H. L., Jr.

    1981-01-01

    An investigation was conducted in the Langley 4 by 7 Meter Tunnel to determine the static longitudinal and lateral directional aerodynamic characteristics of an advanced aspect ratio 10 supercritical wing transport model equipped with a full span leading edge slat as well as part span and full span trailing edge flaps. This wide body transport model was also equipped with spoiler and aileron roll control surfaces, flow through nacelles, landing gear, and movable horizontal tails. Six basic wing configurations were tested: (1) cruise (slats and flaps nested), (2) climb (slats deflected and flaps nested), (3) part span flap, (4) full span flap, (5) full span flap with low speed ailerons, and (6) full span flap with high speed ailerons. Each of the four flapped wing configurations was tested with leading edge slat and trailing edge flaps deflected to settings representative of both take off and landing conditions. Tests were conducted at free stream conditions corresponding to Reynolds number of 0.97 to 1.63 x 10 to the 6th power and corresponding Mach numbers of 0.12 to 0.20, through an angle of attack range of 4 to 24, and a sideslip angle range of -10 deg to 5 deg. The part and full span wing configurations were also tested in ground proximity.

  11. Research on the Solution to Interference between Slat and Pylon of Transport Aircraft%运输机缝翼与挂架干涉解决方法研究

    Institute of Scientific and Technical Information of China (English)

    梁欣杰; 李明华; 孟涛

    2015-01-01

    Several proposals were studied from engineering standpoint to solve the problem of interference between slat and pylon of transport aircraft. Through analyzing the characteristics of each solution and the scope of application, some methods to solve the interference between slat and pylon were proposed for a reference. The methods of solutions can be lfexibly selected for high wing monoplanes according to different feature of the aircraft. But it is appropriate to disconnect the slat for low wing monoplanes.%为解决运输机缝翼与挂架的干涉,从工程设计角度出发,研究了几种解决缝翼与挂架干涉的方案。通过对每种解决方案的特点、适用范围进行分析和研究,给出解决缝翼与挂架干涉问题的参考方法。对于上单翼飞机可以依据自身情况灵活选取解决方案,而下单翼飞机更适合将缝翼断开解决缝翼与挂架的干涉。

  12. Alternative solutions to the concrete fully-slatted floor for the housing of finishing beef cattle: effects on growth performance, health of the locomotor system and behaviour.

    Science.gov (United States)

    Cozzi, G; Tessitore, E; Contiero, B; Ricci, R; Gottardo, F; Brscic, M

    2013-08-01

    The aim of this study was to assess the effect of two potential alternative solutions to the concrete fully-slatted floor (FS), namely, a perforated floor (PF) and a perforated floor coated with a rubber mattress (RM), on growth, locomotor system health, and behaviour of intensively finished young bulls. Forty-eight male beef-crosses (Charolais × Aubrac) were allotted to six pens of eight animals (two pens/floor type) for a finishing period of 175 ± 7 days. Growth was recorded and two health checks and two 8-h behavioural observations were carried out by trained assessors 1 month after the beginning of the trial (Initial) and 2 weeks before slaughter (Final). Feed intake was not affected by floor type, but average daily gain of RM bulls was higher than that of FS (1.37 vs. 1.19 kg, P=0.01), with PF being intermediate (1.27 kg). Behavioural observations showed that FS bulls had a higher number of slipping events (6.5) than PF (2.1; P=0.01) and RM bulls (0.9; Pfloor proved to be a good alternative to FS but it increased the likelihood of overgrown claws due to insufficient hoof wear.

  13. Steady-state liquid sloshing in a rectangular tank with a slat-type screen in the middle: Quasilinear modal analysis and experiments

    Science.gov (United States)

    Faltinsen, O. M.; Firoozkoohi, R.; Timokha, A. N.

    2011-04-01

    Two-dimensional resonant liquid sloshing in a rectangular tank equipped with a central slat-type screen is studied theoretically and experimentally with focus on nonsmall solidity ratios of the screen (0.5≲Sn≲0.95), nonlarge number of slots (N ≲50), and steady-state conditions. The tank is horizontally and harmonically excited with frequencies in a range covering the two lowest primary-excited natural sloshing resonance frequencies in the corresponding clean tank. The liquid depth is finite. Theoretical analysis is based on the multimodal method with linear free-surface conditions and a quadratic pressure drop condition at the screen expressing an "integral" effect of the screen-induced cross-flow separation (or jet flow). New experimental data on the maximum wave elevations at the wall are compared with the theoretical predictions. Very good agreement is shown for the smallest forcing amplitudes (the forcing amplitude-to-tank width ratio is ≈0.001). Increasing the nondimensional forcing amplitude to ≈0.01 leads to discrepancies due to secondary resonance causing the energy context from the two primary-excited antisymmetric modes to other, first of all, symmetric modes. A further increase of the nondimensional forcing amplitude to 0.03 leads to more complex secondary resonance effects. Specific surface wave phenomena, e.g., wave breaking, are experimentally observed and documented by photographs and videos.

  14. Assessment of a fast generated analytical matrix for rotating slat collimation iterative reconstruction: a possible method to optimize the collimation profile

    Science.gov (United States)

    Boisson, F.; Bekaert, V.; Reilhac, A.; Wurtz, J.; Brasse, D.

    2015-03-01

    In SPECT imaging, improvement or deterioration of performance is mostly due to collimator design. Classical SPECT systems mainly use parallel hole or pinhole collimators. Rotating slat collimators (RSC) can be an interesting alternative to optimize the tradeoff between detection efficiency and spatial resolution. The present study was conducted using a RSC system for small animal imaging called CLiR. The CLiR system was used in planar mode only. In a previous study, planar 2D projections were reconstructed using the well-known filtered backprojection algorithm (FBP). In this paper, we investigated the use of the statistical reconstruction algorithm maximum likelihood expectation maximization (MLEM) to reconstruct 2D images with the CLiR system using a probability matrix calculated using an analytic approach. The primary objective was to propose a method to quickly generate a light system matrix, which facilitates its handling and storage, while providing accurate and reliable performance. Two other matrices were calculated using GATE Monte Carlo simulations to investigate the performance obtained using the matrix calculated analytically. The first matrix calculated using GATE took all the physics processes into account, where the second did not consider for the scattering, as the analytical matrix did not take this physics process into account either. 2D images were reconstructed using FBP and MLEM with the three different probability matrices. Both simulated and experimental data were used. A comparative study of these images was conducted using different metrics: the modulation transfert function, the signal-to-noise ratio and quantification measurement. All the results demonstrated the suitability of using a probability matrix calculated analytically. It provided similar results in terms of spatial resolution (about 0.6 mm with differences image.

  15. Solar control: comparison of two new systems with the state of the art on the basis of a new general evaluation method for facades with venetian blinds or other solar control systems

    Energy Technology Data Exchange (ETDEWEB)

    Kuhn, T.E. [Fraunhofer Institute for Solar Energy Systems ISE, Freiburg (Germany)

    2006-06-15

    The author has developed two new sun-shading systems together with two different companies. These systems are compared with state of the art products on the basis of the new general evaluation method for facades with venetian blinds or other solar control systems that has been presented in detail in [T.E. Kuhn, Solar control: a general evaluation method for facades with venetian blinds or other solar control systems to be used 'stand-alone' or within building simulation programs, Energy Buildings, in press]. The main advantage is that the method can take into account realistic user behaviour (different utilisation modes). Without the new methodology, it would not have been possible to recognise the weaknesses of products which are currently on the market. This recognition was the basis for the design of the two new products: 1. The new stainless steel blind s-enn(Registered Trademark) selectively shields certain regions of the sky. This leads to a transparent appearance while direct insolation of the room and the associated glare is prevented in most cases. 2. The special shape of the 'Genius slats' of a new venetian blind ensures good sun-shading properties which are relatively independent of the actual setting of the slats over broad ranges, which ensures robust performance despite so-called 'faulty operation'. In other words: The performance of the new venetian blind is relatively insensitive to different utilisation modes. (author)

  16. Assessment of the potential of solar thermal small power systems in small utilities. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Steitz, P.; Mayo, L.G.; Perkins, S.P. Jr.

    1978-11-01

    This study involved an assessment of the potential economic benefit of small solar thermal electric power systems to small municipal and rural electric utilities. Five different solar thermal small power system configurations were considered in the study representing three different solar thermal technologies. The configurations included: (1) 1-MW, 2-MW, and 10-MW parabolic dish concentrators with a 15-kW heat engine mounted at the focal point of each dish. These systems utilized advanced battery energy storage. (2) A 10-MW system with variable slat concentrators and central steam Rankine energy conversion. This system utilized sensible thermal energy storage. (3) A 50-MW central receiver system consisting of a field of heliostats concentrating energy on a tower-mounted receiver and a central steam Rankine conversion system. This system also utilized sensible thermal storage. The approach used in determining the potential for solar thermal small power systems in the small utility market involved a comparison of the economics of power supply expansion plans for seven hypothetical small utilities through the year 2000 both with and without the solar thermal small power systems. Insolation typical of the Southwestern US was assumed. A comparison of the break-even capital costs with the range of plant costs estimated in this study yields the following conclusions: (1) The parabolic dish concentrator systems could be economically competitive with conventional generation if the lowest capital costs can be achieved. (2) The variable slat concentrator and central receiver systems would have to achieve lower costs than the lowest in the cost ranges generally assumed in the study to become economically competitive. (3) All of the solar thermal plant types are potentially more competitive in utilities which are heavily dependent upon oil.

  17. Low-speed aerodynamic performance of a high-aspect-ratio supercritical-wing transport model equipped with full-span slat and part-span double-slotted flaps

    Science.gov (United States)

    Morgan, H. L., Jr.; Paulson, J. W., Jr.

    1979-01-01

    An investigation was conducted in the Langley V/STOL tunnel to determine the static longitudinal and lateral-directional aerodynamic characteristics of an advanced high-aspect-ratio supercritical-wing transport model equipped with a full-span leading-edge slat and part-span double-slotted trailing-edge flaps. This wide-body transport model was also equipped with spoiler and aileron control surfaces, flow-through nacelles, landing gear, movable horizontal tails, and interchangeable wing tips with aspect ratios of 10 and 12. The model was tested with leading-edge slat and trailing-edge flap combinations representative of cruise, climb, takeoff, and landing wing configurations. The tests were conducted at free-stream conditions corresponding to Reynolds numbers (based on mean geometric chord) of 0.97 to 1.63 x 10 to the 6th power and corresponding Mach numbers of 0.12 to 0.20, through an angle-of-attack range of -2 deg to 24 deg and a sideslip-angle range of -10 deg to 5 deg.

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. 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...

  3. Assessment of the potential of solar thermal small power systems in small utilities

    Science.gov (United States)

    Steitz, P.; Mayo, L. G.; Perkins, S. P., Jr.

    1978-01-01

    The potential economic benefit of small solar thermal electric power systems to small municipal and rural electric utilities is assessed. Five different solar thermal small power system configurations were considered in three different solar thermal technologies. The configurations included: (1) 1 MW, 2 MW, and 10 MW parabolic dish concentrators with a 15 kW heat engine mounted at the focal point of each dish, these systems utilized advanced battery energy storage; (2) a 10 MW system with variable slat concentrators and central steam Rankine energy conversion, this system utilized sensible thermal energy storage; and (3) a 50 MW central receiver system consisting of a field of heliostats concentrating energy on a tower-mounted receiver and a central steam Rankine conversion system, this system also utilized sensible thermal storage. The results are summarized in terms of break-even capital costs. The break-even capital cost was defined as the solar thermal plant capital cost which would have to be achieved in order for the solar thermal plants to penetrate 10 percent of the reference small utility generation mix by the year 2000. The calculated break-even capital costs are presented.

  4. Solar Features - Solar Flares

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A solar flare is a short-lived sudden increase in the intensity of radiation emitted in the neighborhood of sunspots. For many years it was best monitored in the...

  5. 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)

  6. 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…

  7. 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...

  8. 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.

  9. 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.

  10. Projection of distributed-collector solar-thermal electric power plant economics to years 1990-2000

    Science.gov (United States)

    Fujita, T.; Elgabalawi, N.; Herrera, G.; Turner, R. H.

    1977-01-01

    A preliminary comparative evaluation of distributed-collector solar thermal power plants was undertaken by projecting power plant economics of selected systems to the 1990 to 2000 time frame. The selected systems include: (1) fixed orientation collectors with concentrating reflectors and vacuum tube absorbers, (2) one axis tracking linear concentrator including parabolic trough and variable slat designs, and (3) two axis tracking parabolic dish systems including concepts with small heat engine-electric generator assemblies at each focal point as well as approaches having steam generators at the focal point with pipeline collection to a central power conversion unit. Comparisons are presented primarily in terms of energy cost and capital cost over a wide range of operating load factors. Sensitvity of energy costs for a range of efficiency and cost of major subsystems/components is presented to delineate critical technological development needs.

  11. Slat cove filler design for noise reduction based on artificial neural network%基于人工神经网络的缝翼凹槽填充降噪设计

    Institute of Scientific and Technical Information of China (English)

    陶俊; 孙刚; 徐康乐

    2015-01-01

    Airframe noise becomes one of the dominant noise sources during landing and tak-ing off phases of a civil aircraft because that jet engine noise is decreased obviously in recent years.High lift device noise is the main source of airframe noise,decreasing high lift device noise makes a significant contribution to the overall noise reduction for a civil aircraft.Slat cove filler (SCF),as a type of slat noise reduction method,may decrease the aerodynamic performances, such as the maximum lift coefficient and the stall angle.To this situation,a database of SCF is built for a multi-element airfoil,and one of the SCFs in the database is selected as the reference configuration,20 optimized configurations are generated through confidence coefficient reason-ing.Aerodynamic performance of each optimized configuration is predicted by a back propagation (BP)artificial neural network,and the one with the best aerodynamic performance is selected as the design configuration for verifying computation,steady Navier-Stokes simulations are executed to compare aerodynamic performances of the design configuration with that of the baseline config-uration.A hybrid method,combining CFD with acoustic analogy,is applied to compare the acoustic performances of the design configuration with that of the baseline configuration.The re-sults indicate that the noises are reduced significantly at the given observation points by adding the designed SCF,while the aerodynamic performances have been maintained.%缝翼凹槽填充技术作为一种缝翼降噪方法,有可能会造成气动性能的损失,如最大升力系数和失速迎角的减小。基于这种情况,针对某多段翼型建立了缝翼凹槽填充构型的数据库,挑选出参考构型,利用置信度推理确定了优化方向,生成了20个优化构型;采用 back propagation(BP)人工神经网络快速预测各优化构型的气动性能,选择其中气动性能最好的构型作为设计构型进

  12. Solar Collectors

    Science.gov (United States)

    1980-01-01

    Solar Energy's solar panels are collectors for a solar energy system which provides heating for a drive-in bank in Akron, OH. Collectors were designed and manufactured by Solar Energy Products, a firm established by three former NASA employees. Company President, Frank Rom, an example of a personnel-type technology transfer, was a Research Director at Lewis Research Center, which conducts extensive solar heating and cooling research, including development and testing of high-efficiency flat-plate collectors. Rom acquired solar energy expertise which helped the company develop two types of collectors, one for use in domestic/commercial heating systems and the other for drying grain.

  13. Fatigue Test Technology of Slat and Flap with Active Driving and Servo Loading Device%一种主动驱动随动加载的前缘缝翼和襟翼疲劳试验技术

    Institute of Scientific and Technical Information of China (English)

    李小军; 陆慧莲; 李凯

    2014-01-01

    前缘缝翼、襟翼活动面及其支承结构的疲劳试验是民用飞机取证前要开展的一项重要工作。在试验中采用主动驱动和随动加载方法加载,不仅能缩小试验规模,同时可提高试验精度。国内某型机采用此技术成功进行了前缘缝翼、襟翼及其悬挂结构的疲劳试验。从试验件及其支承设计、系统构成和载荷与运行三方面,介绍了一种适用于大中型固定翼飞机前缘缝翼和襟翼的疲劳试验技术。%The fatigue tests on slat, flap and their supporting structures are very important work to be launched for a new airplane before technology certification ( TC) being granted. The loading which adopts active driving and ser-vo loading not only reduces the test scale but also enhances the test accuracy. This technology has been applied to make the fatigue test on some civil aircraft successfully. This paper presents the new fatigue test technology in three aspects:test article with its suspension, test system, load and implementation respectively.

  14. 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....

  15. 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...

  16. 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.

  17. Solar urticaria

    Directory of Open Access Journals (Sweden)

    Srinivas C

    1995-01-01

    Full Text Available A 35-year-old female and a 41-year-old male presented with clinical features suggestive of solar urticaria. The diagnosis of solar urticaria and the effectiveness of a combination of H1 and H2 blocking antihistamines were confirmed by phototesting with a solar simulator

  18. 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...

  19. Solar flair.

    Science.gov (United States)

    Manuel, John S

    2003-02-01

    Design innovations and government-sponsored financial incentives are making solar energy increasingly attractive to homeowners and institutional customers such as school districts. In particular, the passive solar design concept of daylighting is gaining favor among educators due to evidence of improved performance by students working in daylit classrooms. Electricity-generating photovoltaic systems are also becoming more popular, especially in states such as California that have high electric rates and frequent power shortages. To help spread the word about solar power, the U.S. Department of Energy staged its first-ever Solar Decathlon in October 2002. This event featured solar-savvy homes designed by 14 college teams.

  20. Solar Energy: Solar System Economics.

    Science.gov (United States)

    Knapp, Henry H., III

    This module on solar system economics is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy technologies.…

  1. Solar energy

    Energy Technology Data Exchange (ETDEWEB)

    Sommer-Larsen, P.; Krebs, F.C. (Risoe DTU, Roskilde (Denmark)); Plaza, D.M. (Plataforma Solar de Almeria-CIEMAT (Spain))

    2010-11-15

    Solar energy is the most abundant energy resource on earth. In a sustainable future with an ever-increasing demand for energy, we will need to use this resource better. Solar energy technologies either convert sunlight directly into heat and electrical energy or use it to power chemical conversions which create 'solar fuels' or synthetic compounds. Solar heating technologies have developed steadily for many years and solar heating and cooling is one of the world's commonest renewable energy technologies. This chapter, however, focuses on technologies for electricity production and touches more briefly on the prospects for solar fuels. The section on Danish perspectives also discusses solar thermal heating in district heating plants. In recent decades, two technologies for converting solar energy into electrical energy have dominated: photovoltaics (PV) and concentrating solar power (CSP). Today's silicon and thin-film PV technologies are advancing steadily, with new materials and technologies constantly being developed, and there are clear roadmaps for lowering production costs. In the discussion below we assess the maturation potential of currently emerging PV technologies within the next 40 years. Concentrating solar power is already a proven technology, and below we evaluate its potential to become a substantial part of the energy mix by 2050. Solar fuels cover a range of technologies. The chapter is to a great extent based on two recent roadmaps from the International Energy Agency (IEA). Many reports, predictions, scenarios and roadmaps for solar energy deployment exist. The IEA predictions for the penetration of solar energy in the future energy system are low relative to many of the other studies. The IEA roadmaps, however, cover most aspects of the future deployment of the technologies and reference older work. (Author)

  2. 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...

  3. 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.

  4. 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…

  5. 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...

  6. Solar Nexus.

    Science.gov (United States)

    Murphy, Jim

    1980-01-01

    The design team for the Solar Energy Research Institute (SERI) has pushed the state of the energy art to its current limits for the initial phase, with provisions for foreseeable and even speculative future applications. (Author/MLF)

  7. Solar Radio

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Scientists monitor the structure of the solar corona, the outer most regions of the Sun's atmosphere, using radio waves (100?s of MHz to 10?s of GHz). Variations in...

  8. Solar energy engineering

    Energy Technology Data Exchange (ETDEWEB)

    Sayigh, A.A.M. (ed.)

    1977-01-01

    The scope and advantages of solar energy are dealt with. The nature of the sun, the solar radiation spectrum, the estimation of total, direct, and diffuse radiation, and the heat transfer fundamentals for solar energy application are explained. The fundamentals, fabrication, and uses of various water and air heaters are outlined. Optics and concentrating collectors are dealt with, as well as solar furnaces. The various applications of solar energy are discussed, namely, solar pond, solar distillation, photovoltaic conversion of solar energy, solar refrigeration, solar hydrogen production, space applications, and solar measuring equipment. The cost of solar appliances is discussed. (MHR)

  9. Solar Features - Solar Flares - SIDS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Sudden Ionospheric Disturbance (SID) is any of several radio propagation anomalies due to ionospheric changes resulting from solar or geophysical events.

  10. Solar Features - Solar Flares - Patrol

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The H-alpha Flare Patrol identifies time periods each day when the sun is being continuously monitored by select ground-based solar observatories.

  11. Solar Neutrinos

    Science.gov (United States)

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

    1964-12-01

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

  12. Solar fuels

    Energy Technology Data Exchange (ETDEWEB)

    Bolton, J.R.

    1978-11-17

    The paper is concerned with (1) the thermodynamic and kinetic limits for the photochemical conversion and storage of solar energy as it is received on the earth's surface, and (2) the evaluation of a number of possible photochemical reactions with particular emphasis on the production of solar hydrogen from water. Procedures for generating hydrogen fuel are considered. Topics examined include the general requirements for a fuel-generation reaction, the photochemical reaction, limits on the conversion of light energy to chemical energy, an estimate of chemical storage efficiency, and the water decomposition reaction.

  13. Solar Energy

    OpenAIRE

    Sommer-Larsen, Peter; Furbo, Simon

    2014-01-01

    This thesis is about Photovoltaic (PV) cells and its stresses in various directions by calculating the power generated using solar cells under different conditions to improve its efficiency. Our research studies found that using multi-junction cells with larger substrates can increase the efficiency to some extent which in practice is limited to 43 percent. The experiment was conducted using ten solar cells each with an area of 20.9〖cm〗 ^2, where each cell gives 0.5 V and 0.4 A and a 1.25 Ω r...

  14. 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…

  15. Sistema Solar

    OpenAIRE

    Federación de Asociaciones de Astronomía Cielo de Comellas

    2004-01-01

    Lección sobre el Sistema Solar. Curso de Astronomía Básica, segunda edición, impartido por los miembros de la Federación de Asociaciones de Astronomía Cielo de Comellas. Casa de la Ciencia, sábados, del 24 de septiembre al 22 de octubre de 2011

  16. Solar system

    CERN Document Server

    Homer, Charlene

    2007-01-01

    Thrill young astronomers with a journey through our Solar System. Find out all about the Inner and Outer Planets, the Moon, Stars, Constellations, Asteroids, Meteors and Comets. Using simplified language and vocabulary, concepts such as planetary orbits, the asteroid belt, the lunar cycle and phases of the moon, and shooting stars are all explored.

  17. 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.

  18. 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…

  19. 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…

  20. Concentrated solar power generation using solar receivers

    Energy Technology Data Exchange (ETDEWEB)

    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.

  1. Fisica solare

    CERN Document Server

    Degl’Innocenti, Egidio Landi

    2008-01-01

    Il volume è un'introduzione alla Fisica Solare che si propone lo scopo di illustrare alla persona che intende avvicinarsi a questa disciplina (studenti, dottori di ricerca, ricercatori) i meccanismi fisici che stanno alla base della complessa fenomenologia osservata sulla stella a noi più vicina. Il volume non ha la pretesa di essere esauriente (basta pensare che la fisica solare spazia su un gran numero di discipline, quali la Fisica Nucleare, la Termodinamica, L'Elettrodinamica, la Fisica Atomica e Molecolare, la Spettoscopia in tutte le bande dello spettro elettromagnetico, la Magnetoidrodinamica, la Fisica del Plasma, lo sviluppo di nuova strumentazione, l'Ottica, ecc.). Piuttosto, sono stati scelti un numero di argomenti di rilevanza fondamentale nello studio presente del Sole (soprattutto nei riguardi delle osservazioni da terra con grandi telescopi) e su tali argomenti si è cercato di dare una panoramica generale, inclusiva dell'evoluzione storica, senza scendere in soverchi dettagli. Siccome la Fis...

  2. Solar club

    CERN Multimedia

    Solar club

    2013-01-01

    SOLAR CLUB Le  CERN-Solar-Club souhaite une  très bonne année 2013 à tous les Cernois et Cernoises, et remercie encore une fois  tous ceux et celles qui, fin octobre, par leur vote, nous ont permis de finir dans les 5 premiers du concours "Conforama Solidaire" et ainsi financer nôtre projet "énergie solaire et eau potable pour Kilela Balanda" en République Démocratique du Congo (voir : http://www.confo.ch/solidarite/?lang=fr). Nous vous annoncons également notre Assemblée Générale Annuelle jeudi 21 février à 18 h 00 Salle C, 1er étage, Bât. 61 Vous êtes les bienvenus si vous souhaitez en savoir un peu plus sur les énergies renouvelables.

  3. Energia Solar

    Directory of Open Access Journals (Sweden)

    Paulo Henrique Dias de Borba

    2011-07-01

    Full Text Available Este projeto trata da implantação de células fotovoltaicas na forma de postes independentes na área externa da escola Oswaldo Cruz em Sinop- MT, mais especificamente no estacionamento do local, e também a implantação de placas solares nas guaritas e nos estacionamentos cobertos, tornando-os semi-sustentáveis.

  4. Solar Chameleons

    CERN Document Server

    Brax, Philippe

    2010-01-01

    We analyse the creation of chameleons deep inside the sun and their subsequent conversion to photons near the magnetised surface of the sun. We find that the spectrum of the regenerated photons lies in the soft X-ray region, hence addressing the solar corona problem. Moreover, these back-converted photons originating from chameleons have an intrinsic difference with regenerated photons from axions: their relative polarisations are mutually orthogonal before Compton interacting with the surrounding plasma. Depending on the photon-chameleon coupling and working in the strong coupling regime of the chameleons to matter, we find that the induced photon flux, when regenerated resonantly with the surrounding plasma, coincides with the solar flux within the soft X-ray energy range. Moreover, using the soft X-ray solar flux as a prior, we find that with a strong enough photon-chameleon coupling the chameleons emitted by the sun could lead to a regenerated photon flux in the CAST pipes, which could be within the reach...

  5. Nanostructured Solar Cells

    Science.gov (United States)

    Chen, Guanying; Ning, Zhijun; Ågren, Hans

    2016-01-01

    We are glad to announce the Special Issue “Nanostructured Solar Cells”, published in Nanomaterials. This issue consists of eight articles, two communications, and one review paper, covering major important aspects of nanostructured solar cells of varying types. From fundamental physicochemical investigations to technological advances, and from single junction solar cells (silicon solar cell, dye sensitized solar cell, quantum dots sensitized solar cell, and small molecule organic solar cell) to tandem multi-junction solar cells, all aspects are included and discussed in this issue to advance the use of nanotechnology to improve the performance of solar cells with reduced fabrication costs.

  6. Nanostructured Solar Cells.

    Science.gov (United States)

    Chen, Guanying; Ning, Zhijun; Ågren, Hans

    2016-08-09

    We are glad to announce the Special Issue "Nanostructured Solar Cells", published in Nanomaterials. This issue consists of eight articles, two communications, and one review paper, covering major important aspects of nanostructured solar cells of varying types. From fundamental physicochemical investigations to technological advances, and from single junction solar cells (silicon solar cell, dye sensitized solar cell, quantum dots sensitized solar cell, and small molecule organic solar cell) to tandem multi-junction solar cells, all aspects are included and discussed in this issue to advance the use of nanotechnology to improve the performance of solar cells with reduced fabrication costs.

  7. 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

  8. Solar Sails

    Science.gov (United States)

    Young, Roy

    2006-01-01

    The Solar Sail Propulsion investment area has been one of the three highest priorities within the In-Space Propulsion Technology (ISPT) Project. In the fall of 2003, the NASA Headquarters' Science Mission Directorate provided funding and direction to mature the technology as far as possible through ground research and development from TRL 3 to 6 in three years. A group of experts from government, industry, and academia convened in Huntsville, Alabama to define technology gaps between what was needed for science missions to the inner solar system and the current state of the art in ultra1ightweight materials and gossamer structure design. This activity set the roadmap for development. The centerpiece of the development would be the ground demonstration of scalable solar sail systems including masts, sails, deployment mechanisms, and attitude control hardware and software. In addition, new materials would be subjected to anticipated space environments to quantify effects and assure mission life. Also, because solar sails are huge structures, and it is not feasible to validate the technology by ground test at full scale, a multi-discipline effort was established to develop highly reliable analytical models to serve as mission assurance evidence in future flight program decision-making. Two separate contractor teams were chosen to develop the SSP System Ground Demonstrator (SGD). After a three month conceptual mission/system design phase, the teams developed a ten meter diameter pathfinder set of hardware and subjected it to thermal vacuum tests to compare analytically predicted structural behavior with measured characteristics. This process developed manufacturing and handling techniques and refined the basic design. In 2005, both contractor teams delivered 20 meter, four quadrant sail systems to the largest thermal vacuum chamber in the world in Plum Brook, Ohio, and repeated the tests. Also demonstrated was the deployment and articulation of attitude control

  9. Solar neutrinos and the solar composition problem

    CERN Document Server

    Pena-Garay, Carlos

    2008-01-01

    Standard solar models (SSM) are facing nowadays a new puzzle: the solar composition problem. New determinations of solar metal abundances lead SSM calculations to conflict with helioseismological measurements, showing discrepancies that extend from the convection zone to the solar core and can not be easily assigned to deficiencies in the modelling of the solar convection zone. We present updated solar neutrino fluxes and uncertainties for two SSM with high (old) and low (new) solar metallicity determinations. The uncertainties in iron and carbon abundances are the largest contribution to the uncertainties of the solar neutrino fluxes. The uncertainty on the ^14N+p -> ^15O+g rate is the largest of the non-composition uncertainties to the CNO neutrino fluxes. We propose an independent method to help identify which SSM is the correct one. Present neutrino data can not distinguish the solar neutrino predictions of both models but ongoing measurements can help to solve the puzzle.

  10. BLM Solar Energy Zones

    Data.gov (United States)

    Bureau of Land Management, Department of the Interior — Priority development areas for utility-scale solar energy facilities as identified in the Solar PEIS Record of Decision. An additional Solar Energy Zone identified...

  11. Solar Electricity

    Science.gov (United States)

    1988-01-01

    ARCO Solar manufactures PV Systems tailored to a broad variety of applications. PV arrays are routinely used at remote communications installations to operate large microwave repeaters, TV and radio repeaters rural telephone, and small telemetry systems that monitor environmental conditions. Also used to power agricultural water pumping systems, to provide electricity for isolated villages and medical clinics, for corrosion protection for pipelines and bridges, to power railroad signals, air/sea navigational aids, and for many types of military systems. ARCO is now moving into large scale generation for utilities.

  12. Solar Generator

    Science.gov (United States)

    1985-01-01

    The Vanguard I dish-Stirling module program, initiated in 1982, produced the Vanguard I module, a commercial prototype erected by the Advanco Corporation. The module, which automatically tracks the sun, combines JPL mirrored concentrator technology, an advanced Stirling Solar II engine/generator, a low cost microprocessor-controlled parabolic dish. Vanguard I has a 28% sunlight to electricity conversion efficiency. If tests continue to prove the system effective, Advanco will construct a generating plant to sell electricity to local utilities. An agreement has also been signed with McDonnell Douglas to manufacture a similar module.

  13. Solar greenhouses in Minnesota

    Energy Technology Data Exchange (ETDEWEB)

    Polich, M.

    1981-12-01

    After a discussion of solar greenhouse phenomena and the potential for heat collection and food production, design recommendations are provided for attached heat collecting solar sunspaces and for attached food producing solar greenhouses. Also, design of a single solar structure to maximize heat collection and food production is considered. A method of predicting the performance for attached heat collecting solar sunspaces is given in which the solar savings fraction is calculated. (LEW)

  14. Mobile Solar Tracker Facility

    Data.gov (United States)

    Federal Laboratory Consortium — NIST's mobile solar tracking facility is used to characterize the electrical performance of photovoltaic panels. It incorporates meteorological instruments, a solar...

  15. 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.

  16. Solar Club

    CERN Multimedia

    Solar Club

    2010-01-01

    Le CERN Solar-Club vous invite à la présentation de sa participation dans : The Cyprus Institute Solar Car Challenge du 18 au 20 juin à Chypre . en réponse à l’invitation dudit institut, dans le cadre de la demande de Chypre pour joindre le CERN . Le Club y participera avec son vénérable Photon rénové , et la Dyane E-Solaire d’un de ses membres, rénové aussi . Après la présentation, le forum est ouvert pour toutes vos questions et propositions diverses, également dans d’autres domaines des énergies renouvelables . C’est aussi l’occasion pour joindre le Club ! Où, et Quand ? Le Mercredi 7 Avril à 19 h 00, au 6ème étage du Bât. Principal, (60-6-015) à la suite de l’AG des membres du Club , à 18h00 dans...

  17. 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...

  18. Solar Energy: Solar and the Weather.

    Science.gov (United States)

    Knapp, Henry H., III

    This module on solar and the weather is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy technologies.…

  19. Solar Energy: Solar System Design Fundamentals.

    Science.gov (United States)

    Knapp, Henry H., III

    This module on solar system design fundamentals is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy…

  20. Solar models and solar neutrino oscillations

    OpenAIRE

    2004-01-01

    We provide a summary of the current knowledge, theoretical and experimental, of solar neutrino fluxes and of the masses and mixing angles that characterize solar neutrino oscillations. We also summarize the principal reasons for doing new solar neutrino experiments and what we think may be learned from the future measurements.

  1. EDITORIAL Solar harvest Solar harvest

    Science.gov (United States)

    Demming, Anna

    2010-12-01

    The first observations of the photoelectric effect date back to the early 19th century from work by Alexandre Edmond Becquerel, Heinrich Hertz, Wilhelm Hallwachs and J J Thomson. The theory behind the phenomena was clarified in a seminal paper by Einstein in 1905 and became an archetypical feature of the wave-particle description of light. A different manifestation of quantised electron excitation, whereby electrons are not emitted but excited into the valence band of the material, is what we call the photoconductive effect. As well as providing an extension to theories in fundamental physics, the phenomenon has spawned a field with enormous ramifications in the energy industry through the development of solar cells. Among advances in photovoltaic technology has been the development of organic photovoltaic technology. These devices have many benefits over their inorganic counterparts, such as light-weight, flexible material properties, as well as versatile materials' synthesis and low-cost large-scale production—all highly advantageous for manufacturing. The first organic photovoltaic systems were reported over 50 years ago [1], but the potential of the field has escalated in recent years in terms of efficiency, largely through band offsetting. Since then, great progress has been made in studies for optimising the efficiency of organic solar cells, such as the work by researchers in Germany and the Netherlands, where investigations were made into the percentage composition and annealing effects on composites of poly(3-hexylthiophene) (P3HT) and the fullerene derivative [6,6]-phenyl-C61 butyric acid methyl ester (PCBM) [2]. Hybrid devices that aim to exploit the advantages of both inorganic and organic constituents have also proven promising. One example of this is the work reported by researchers in Tunisia and France on a systematic study for optimising the composition morphology of TiO2 nanoparticles in poly(N-vinylcarbazole) (PVK), which also led to insights

  2. First flight of the Gamma-Ray Imager/Polarimeter for Solar flares (GRIPS) instrument

    Science.gov (United States)

    Duncan, Nicole; Saint-Hilaire, P.; Shih, A. Y.; Hurford, G. J.; Bain, H. M.; Amman, M.; Mochizuki, B. A.; Hoberman, J.; Olson, J.; Maruca, B. A.; Godbole, N. M.; Smith, D. M.; Sample, J.; Kelley, N. A.; Zoglauer, A.; Caspi, A.; Kaufmann, P.; Boggs, S.; Lin, R. P.

    2016-07-01

    The Gamma-Ray Imager/Polarimeter for Solar flares (GRIPS) instrument is a balloon-borne telescope designed to study solar- are particle acceleration and transport. We describe GRIPS's first Antarctic long-duration flight in January 2016 and report preliminary calibration and science results. Electron and ion dynamics, particle abundances and the ambient plasma conditions in solar flares can be understood by examining hard X-ray (HXR) and gamma-ray emission (20 keV to 10 MeV). Enhanced imaging, spectroscopy and polarimetry of are emissions in this energy range are needed to study particle acceleration and transport questions. The GRIPS instrument is specifically designed to answer questions including: What causes the spatial separation between energetic electrons producing hard X-rays and energetic ions producing gamma-ray lines? How anisotropic are the relativistic electrons, and why can they dominate in the corona? How do the compositions of accelerated and ambient material vary with space and time, and why? GRIPS's key technological improvements over the current solar state of the art at HXR/gamma-ray energies, the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI), include 3D position-sensitive germanium detectors (3D-GeDs) and a single-grid modulation collimator, the multi-pitch rotating modulator (MPRM). The 3D-GeDs have spectral FWHM resolution of a few hundred keV and spatial resolution 150 keV, the energy deposition sites can be tracked, providing polarization measurements as well as enhanced background reduction through Compton imaging. Each of GRIPS's detectors has 298 electrode strips read out with ASIC/FPGA electronics. In GRIPS's energy range, indirect imaging methods provide higher resolution than focusing optics or Compton imaging techniques. The MPRM gridimaging system has a single-grid design which provides twice the throughput of a bi-grid imaging system like RHESSI. The grid is composed of 2.5 cm deep tungsten-copper slats, and quasi

  3. Solar pond

    Science.gov (United States)

    Miller, C. G.; Stephens, J. B. (Inventor)

    1978-01-01

    Shallow pools of liquid to collect low-temperature solar generated thermal energy are described. Narrow elongated trenches, grouped together over a wide area, are lined with a heat-absorbing black liner. The heat-absorbing liquid is kept separate from the thermal energy removing fluid by means such as clear polyethylene material. The covering for the pond may be a fluid or solid. If the covering is a fluid, fire fighting foam, continuously generated, or siloons are used to keep the surface covering clean and insulated. If the thermal energy removing fluid is a gas, a fluid insulation layer contained in a flat polyethlene tubing is used to cover the pond. The side of the tube directed towards the sun is treated to block out ultraviolet radiation and trap in infrared radiation.

  4. Solar cycle variations in the solar wind

    Science.gov (United States)

    Freeman, John W.; Lopez, Ramon E.

    1986-01-01

    The solar cycle variations of various solar wind parameters are reviewed. It is shown that there is a gradual decrease in the duration of high-speed streams from the declining phase of solar cycle 20 through the ascending phase of cycle 21 and a corresponding decrease in the annual average of the proton speed toward solar maximum. Beta, the ratio of the proton thermal pressure to magnetic pressure, undergoes a significant solar cycle variation, as expected from the variation in the IMF. Individual hourly averages of beta often exceed unity with 20 cases exceeding 10 and one case as high as 25. The Alfven Mach number shows a solar cycle variation similar to beta, lower aboard solar maximum. High-speed streams can be seen clearly in epsilon and the y component of the interplanetary magnetic field.

  5. Photovoltaic solar concentrator

    Energy Technology Data Exchange (ETDEWEB)

    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.

  6. 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)

  7. Solar collector array

    Energy Technology Data Exchange (ETDEWEB)

    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.

  8. Development of Solar Research

    Science.gov (United States)

    Wittmann, Axel D.; Wolfschmidt, Gudrun; Duerbeck, Hilmar W.

    Originally based on a workshop on “Development of Solar Research”, held in Freiburg/Breisgau, this book contains articles on megalithic structures, the Nebra sky-disk, ancient sun cults, the observation of sunspots, the photography of the sun during eclipses, eclipse maps and expeditions, solar telescopes, solar physics during the Nazi era, archives of solar observations, scientific ballooning for solar research, site-testing on the Canary Islands, as well as on international cooperation.

  9. Solar Club

    CERN Multimedia

    Solar Club

    2012-01-01

      Le  CERN Solar Club tiendra son Assemblée Générale le Mercredi  4 avril, à 18h00 dans la salle C, bat.61, 1e étage de 18h00  à  19h30. Grande table ronde avec  présentations de projets concernant toute forme d’Energie  Renouvelable par des membres du club,  et… par  VOUS, nos invités. Au programme : - L’E-push : petite remorque électrique, qui pousse vôtre vélo par Robert Becker. - Le Stockage Saisonnier Sous-Lacustre d’Energie Solaire (S3LES) par  William van Sprolant. - Compte-Rendu de plusieurs conférences récentes concernant les E.R. par Jacques Dupin. - VOS  Projets ou Sujets (contactez : paul.gelissen@orange.fr). - Partie «administrative» avec rapport d’activités, rapport fina...

  10. Predictability of Solar Flares

    Science.gov (United States)

    Mares, Peter; Balasubramaniam, K. S.

    2009-05-01

    Solar flares are significant drivers of space weather. With the availability of high cadence solar chromospheric and photospheric data from the USAF's Optical Solar PAtrol Network (OSPAN; photosphere and chromosphere imaging) Telescope and the Global Oscillations Network Group (GONG; photosphere magnetic imaging), at the National Solar Observatory, we have gained insights into potential uses of the data for solar flare prediction. We apply the Principal Component Analysis (PCA) to parameterize the flaring system and extract consistent observables at solar chromospheric and photospheric layers that indicate a viable recognition of flaring activity. Rather than limiting ourselves to a few known indicators of solar activity, PCA helps us to characterize the entire system using several tens of variables for each observed layer. The components of the Eigen vectors derived from PCA help us recognize and quantify innate characteristics of solar flares and compare them. We will present an analysis of these results to explore the viability of PCA to assist in predicting solar flares.

  11. 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.

  12. 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.

  13. Solar technology applications: a survey of solar powered irrigation systems

    Energy Technology Data Exchange (ETDEWEB)

    Newkirk, H.W.

    1978-04-17

    Published information on solar powered irrigation systems is presented. Thermal solar systems, thermoelectric solar systems, and photovoltaic solar systems are included. A bibliography and survey of on-going work is presented. (WHK)

  14. Generation solar case study : solar summer camp

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    This document presented a case study of the use of solar power at camp Tanamakoon in Ontario's Algonquin Park. It discussed camp facilities which include solar powered composting toilets and solar heated showers. Composting, recycling, and use of environmentally friendly products were also discussed. The camp also has a grid interactive solar electric system and a solar water heating system. The solar electric system provides backup power to critical loads such as safety lights and an emergency fridge and is also connected to the existing grid electricity system. Any excess energy from the solar system can be used by other kitchen appliances or, any other load anywhere in the camp. The main user of the solar heated water is a large automatic dishwasher which has as a built-in boost heater for those days when the solar heated water is insufficiently hot to sanitize dishes. It was concluded that while camp utility bills have been reduced by this investment in renewable energy technology, the primary objectives of the project were the protection of Tanamakoon's pristine Algonquin environment and the attraction and retention of clients for the camp by enhancing the camping experience. fig.

  15. Spectropolarimetry of Solar Corona during Solar Eclipses

    Science.gov (United States)

    Qu, Zhongquan

    2017-08-01

    We present the results from spectropolarimetry of solar corona. These observations were conducted during solar eclipses in 2008 China, 2013 Gabon, and probably 2017 United States of America respectively. From the former two observations, it is shown that the patterns of linear polarization of radiation from the solar corona are very abundant, and the abundance may be related to the complexity of mass motions and magnetic configuration in the corona. And the spectropolarimetry during solar eclipses may open a new window to probe precisely the physical features of the local corona, especially its magnetic configuration.

  16. Solar prominences

    Science.gov (United States)

    Schmieder, Brigitte; Aulanier, Guillaume; Török, Tibor

    2009-03-01

    Solar filaments (or prominences) are magnetic structures in the corona. They can be represented by twisted flux ropes in a bipolar magnetic environment. In such models, the dipped field lines of the flux rope carry the filament material and parasitic polarities in the filament channel are responsible for the existence of the lateral feet of prominences. Very simple laws do exist for the chirality of filaments, the so-called “filament chirality rules”: commonly dextral/sinistral filaments corresponding to left- (resp. right) hand magnetic twists are in the North/South hemisphere. Combining these rules with 3D weakly twisted flux tube models, the sign of the magnetic helicity in several filaments were identified. These rules were also applied to the 180° disambiguation of the direction of the photospheric transverse magnetic field around filaments using THEMIS vector magnetograph data (López Ariste et al. 2006). Consequently, an unprecedented evidence of horizontal magnetic support in filament feet has been observed, as predicted by former magnetostatic and recent MHD models. The second part of this review concerns the role of emerging flux in the vicinity of filament channels. It has been suggested that magnetic reconnection between the emerging flux and the pre-existing coronal field can trigger filament eruptions and CMEs. For a particular event, observed with Hinode/XRT, we observe signatures of such a reconnection, but no eruption of the filament. We present a 3D numerical simulation of emerging flux in the vicinity of a flux rope which was performed to reproduce this event and we briefly discuss, based on the simulation results, why the filament did not erupt.

  17. California solar data manual

    Energy Technology Data Exchange (ETDEWEB)

    Berdahl, P.; Grether, D.; Martin, M.; Wahlig, M.

    1978-01-01

    Factors that determined the data contents of the manual are presented. Estimates of errors in the data are provided, and the impact of these errors on solar design is discussed. The state is divided into 15 solar zones of roughly similar solar radiation conditions, which are illustrated along with page references to the most relevant solar and climate data. A guide to the data tables and graphs is provided, which are displayed under solar, climate, and sky charts. A guide is given to simplified design methods to predict performance and cost of solar heating and cooling systems. (MHR)

  18. Solar Energy Automobile

    OpenAIRE

    He, Jianhua

    2014-01-01

    The thesis was to design a solar energy automobile, which is using solar power as energy re-source. At the moment, Finland was chosen as an example place. It was necessary to calculate the related data, which are the solar angle and the day length when designing the solar energy automobile. Also the seats and dashboard to improve the performance. Actually, in Finland it is possible to use solar energy automobile in summer. But in winter, the day length is so short and the solar constant i...

  19. 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 ...

  20. Solar Thermal Propulsion

    Science.gov (United States)

    Gerrish, Harold P., Jr.

    2003-01-01

    This paper presents viewgraphs on Solar Thermal Propulsion (STP). Some of the topics include: 1) Ways to use Solar Energy for Propulsion; 2) Solar (fusion) Energy; 3) Operation in Orbit; 4) Propulsion Concepts; 5) Critical Equations; 6) Power Efficiency; 7) Major STP Projects; 8) Types of STP Engines; 9) Solar Thermal Propulsion Direct Gain Assembly; 10) Specific Impulse; 11) Thrust; 12) Temperature Distribution; 13) Pressure Loss; 14) Transient Startup; 15) Axial Heat Input; 16) Direct Gain Engine Design; 17) Direct Gain Engine Fabrication; 18) Solar Thermal Propulsion Direct Gain Components; 19) Solar Thermal Test Facility; and 20) Checkout Results.

  1. Solar Energy Automobile

    OpenAIRE

    He, Jianhua

    2014-01-01

    The thesis was to design a solar energy automobile, which is using solar power as energy re-source. At the moment, Finland was chosen as an example place. It was necessary to calculate the related data, which are the solar angle and the day length when designing the solar energy automobile. Also the seats and dashboard to improve the performance. Actually, in Finland it is possible to use solar energy automobile in summer. But in winter, the day length is so short and the solar constant i...

  2. PEROVSKITE SOLAR CELLS (REVIEW ARTICLE)

    OpenAIRE

    Benli, Deniz Ahmet

    2015-01-01

    A solar cell is a device that converts sunlight into electricity. There are different types of solar cells but this report mainly focuses on a type of new generation solar cell that has the name organo-metal halide perovskite, shortly perovskite solar cells. In this respect, the efficiency of power conversion is taken into account to replace the dominancy of traditional and second generation solar cell fields by perovskite solar cells. Perovskite solar cell is a type of solar cell including a...

  3. Aeronet Solar Flux

    Data.gov (United States)

    National Aeronautics and Space Administration — SolRad-Net (Solar Radiation Network) is an established network of ground-based sensors providing high-frequency solar flux measurements in quasi-realtime to the...

  4. Solar energy engineering

    Energy Technology Data Exchange (ETDEWEB)

    Hsieh, J.S.

    1986-01-01

    This book introduces the reader to solar energy engineering, covering topics such as radiation, absorption, its practical applications in space and hot water heating, and solar geometrical and geographical forms.

  5. 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)

  6. Solar Thermal Rocket Propulsion

    Science.gov (United States)

    Sercel, J. C.

    1986-01-01

    Paper analyzes potential of solar thermal rockets as means of propulsion for planetary spacecraft. Solar thermal rocket uses concentrated Sunlight to heat working fluid expelled through nozzle to produce thrust.

  7. Solar Resource Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Renne, D.; George, R.; Wilcox, S.; Stoffel, T.; Myers, D.; Heimiller, D.

    2008-02-01

    This report covers the solar resource assessment aspects of the Renewable Systems Interconnection study. The status of solar resource assessment in the United States is described, and summaries of the availability of modeled data sets are provided.

  8. Solar-Collector Radiometer

    Science.gov (United States)

    Kendall, J. M., Jr

    1984-01-01

    Water-cooled Kendall radiometer measures output of solar energy concentrators. Unit measures irradiance up to 30,000 solar constants with 1 percent accuracy and responds to wavelengths from ultraviolet to far infrared.

  9. Solar Dynamics Observatory

    Data.gov (United States)

    National Aeronautics and Space Administration — A searchable database of all Solar Dynamics Observatory data including EUV, magnetograms, visible light and X-ray. SDO: The Solar Dynamics Observatory is the first...

  10. Future Solar Neutrino Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Nakahata, M. [Kamioka Observatory, Institute for Cosmic Ray research, University of Tokyo, Higashi-Mozumi, Kamioka-cho, Hida-shi, Gifu, Japan, 506-1205 (Japan)]. E-mail: nakahata@suketto.icrr.u-tokyo.ac.jp

    2005-08-15

    The value of future solar neutrino experiments is discussed from particle physics and astrophysics points of view based on current understanding of solar neutrino oscillations. R and D statuses of future experiments are also discussed.

  11. Solar Indices - Sunspot Numbers

    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...

  12. Solar Indices - Plage Regions

    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...

  13. Solar radiation models - review

    Directory of Open Access Journals (Sweden)

    M. Jamil Ahmad, G.N. Tiwari

    2010-05-01

    Full Text Available In the design and study of solar energy, information on solar radiation and its components at a given location is very essential. Solar radiation data are required by solar engineers, architects, agriculturists and hydrologists for many applications such as solar heating, cooking, drying and interior illumination of buildings. For this purpose, in the past, several empirical correlations have been developed in order to estimate the solar radiation around the world. The main objective of this study is to review the global solar radiation models available in the literature. There are several formulae which relate global radiation to other climatic parameters such as sunshine hours, relative humidity and maximum temperature. The most commonly used parameter for estimating global solar radiation is sunshine duration. Sunshine duration can be easily and reliably measured and data are widely available.

  14. Solar Wind Five

    Science.gov (United States)

    Neugebauer, M. (Editor)

    1983-01-01

    Topics of discussion were: solar corona, MHD waves and turbulence, acceleration of the solar wind, stellar coronae and winds, long term variations, energetic particles, plasma distribution functions and waves, spatial dependences, and minor ions.

  15. Beijing Tsinghua Solar Ltd.

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Beijing Tsinghua Solar Ltd. is backed by Tsinghua University, one of the most prestigious universities in China. Tsinghua Solar invented "graded Al-N/Al selective coating," which is the key technology of all-glass evacuated solar collector tubes. The company owns the independent intellectual property rights over the key technology of all-glass vacuum solar water heaters. The registered capital of the company is 153.5 mil-

  16. Durable solar mirror films

    Energy Technology Data Exchange (ETDEWEB)

    O' Neill, Mark B.; Henderson, Andrew J.; Hebrink, Timothy J.; Katare, Rajesh K.; Jing, Naiyong; North, Diane; Peterson, Eric M.

    2017-02-14

    The present disclosure generally relates to durable solar mirror films, methods of making durable solar mirror films, and constructions including durable solar mirror films. In one embodiment, the present disclosure relates to a solar mirror film comprising: a multilayer optical film layer including having a coefficient of hygroscopic expansion of less than about 30 ppm per percent relative humidity; and a reflective layer having a coefficient of hygroscopic expansion.

  17. Solar Neutrino Decay

    CERN Document Server

    Acker, A; Acker, Andy; Pakvasa, Sandip

    1994-01-01

    We re-examine the neutrino decay solution to the solar neutrino problem in light of the new data from Gallex II and Kamiokande III. We compare the experimental data with the solar models of Bahcall and Pinsonneault and Turck-Chieze and find that neutrino decay is ruled out as a solution to the solar neutrino problem at better than the 98\\% c.l. even when solar model uncertainties are taken into account.

  18. Solar mobile power supply

    OpenAIRE

    Hu, Libian

    2014-01-01

    The solar mobile power supply is a comprehensive energy saving and environment protective product. Besides, it consists of solar panels, storage battery and controller as well as other important components. Based on the traditional solar charging circuit, this solar power supply combines the 5V USB interface and 12V adjustable circuit as well as the 220V inverter and power adapter to greatly improve the function of the power system.

  19. Pointing a solar telescope

    Science.gov (United States)

    Wallace, Patrick

    2016-07-01

    As far as pointing is concerned, a solar telescope is merely an ordinary astronomical telescope but with enhancements for observing solar and coronal features. The paper discusses the additional coordinate systems that need to be supported, shows how to generate the required solar ephemerides (both orbital and physical), and sets out a suitable application programming interface for the telescope control system to use when making solar observations.

  20. 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…

  1. 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…

  2. Inexpensive Photovoltaic Solar Radiometer.

    Science.gov (United States)

    Kissner, Fritz

    1981-01-01

    Describes a low-cost instrument using a solar cell as a sensor to measure both instantaneous and integrated value of solar flux. Constructing and calibrating such an instrument constitutes an undergraduate experimental project, affording students an opportunity to examine a variety of aspects associated with solar energy measurements. (Author/SK)

  3. Solar energy directories

    Energy Technology Data Exchange (ETDEWEB)

    Frankena, F.

    1984-01-01

    This annotated bibliography lists 275 directories relating to solar energy and renewable energy resources. The references include the newsletters and in-house publications of small firms and groups, plans and designs for solar housing, catalogs, and directories of agencies and organizations involved in solar energy. The references are listed in alphabetical order.

  4. Experimenting with Solar Energy

    Science.gov (United States)

    Roman, Harry T.

    2004-01-01

    Over the past 25 years, the author has had the opportunity to study the subject of solar energy and to get involved with the installation, operation, and testing of solar energy systems. His work has taken him all over the United States and put him in contact with solar experts from around the world. He has also had the good fortune of seeing some…

  5. 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.

  6. Nanostructured Organic Solar Cells

    DEFF Research Database (Denmark)

    Radziwon, Michal Jędrzej; Rubahn, Horst-Günter; Madsen, Morten

    Recent forecasts for alternative energy generation predict emerging importance of supporting state of art photovoltaic solar cells with their organic equivalents. Despite their significantly lower efficiency, number of application niches are suitable for organic solar cells. This work reveals...... the principles of bulk heterojunction organic solar cells fabrication as well as summarises major differences in physics of their operation....

  7. Inexpensive Photovoltaic Solar Radiometer.

    Science.gov (United States)

    Kissner, Fritz

    1981-01-01

    Describes a low-cost instrument using a solar cell as a sensor to measure both instantaneous and integrated value of solar flux. Constructing and calibrating such an instrument constitutes an undergraduate experimental project, affording students an opportunity to examine a variety of aspects associated with solar energy measurements. (Author/SK)

  8. 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…

  9. Solar tracking system

    Energy Technology Data Exchange (ETDEWEB)

    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.

  10. 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…

  11. 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

  12. 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

  13. Solar Cycle #24 and the Solar Dynamo

    Science.gov (United States)

    Schatten, Kenneth; Pesnell, W. Dean

    2007-01-01

    We focus on two solar aspects related to flight dynamics. These are the solar dynamo and long-term solar activity predictions. The nature of the solar dynamo is central to solar activity predictions, and these predictions are important for orbital planning of satellites in low earth orbit (LEO). The reason is that the solar ultraviolet (UV) and extreme ultraviolet (EUV) spectral irradiances inflate the upper atmospheric layers of the Earth, forming the thermosphere and exosphere through which these satellites orbit. Concerning the dynamo, we discuss some recent novel approaches towards its understanding. For solar predictions we concentrate on a solar precursor method, in which the Sun's polar field plays a major role in forecasting the next cycle s activity based upon the Babcock-Leighton dynamo. With a current low value for the Sun s polar field, this method predicts that solar cycle #24 will be one of the lowest in recent times, with smoothed F10.7 radio flux values peaking near 130 plus or minus 30 (2 sigma), in the 2013 timeframe. One may have to consider solar activity as far back as the early 20th century to find a cycle of comparable magnitude. Concomitant effects of low solar activity upon satellites in LEO will need to be considered, such as enhancements in orbital debris. Support for our prediction of a low solar cycle #24 is borne out by the lack of new cycle sunspots at least through the first half of 2007. Usually at the present epoch in the solar cycle (approx. 7+ years after the last solar maximum), for a normal size following cycle, new cycle sunspots would be seen. The lack of their appearance at this time is only consistent with a low cycle #24. Polar field observations of a weak magnitude are consistent with unusual structures seen in the Sun s corona. Polar coronal holes are the hallmarks of the Sun's open field structures. At present, it appears that the polar coronal holes are relatively weak, and there have been many equatorial coronal holes

  14. A solar power plant

    Energy Technology Data Exchange (ETDEWEB)

    Avakyan, Yu.V.; Dabagyan, T.N.; Gagiyan, L.A.; Kharapetyan, G.S.; Vartanyan, A.V.

    1984-01-01

    This invention is designed for solar energy collectors in the form of heat pipes. A solar power plant is proposed that contains a solar concentrator in the form of at least one heat pipe with evaporation and condensation sections, the first of which is constructed to absorb solar emission and the second located in a heat exchanger equipped with inlet and outlet pipes. In order to simplify the design, the solar power plant is equipped with an additional heat exchanger connected through a connector to the inlet and outlet pipes, while the evaporation section holds an additional section in the lower half, within the auxiliary heat exchanger. During operation as a solar energy collector, the evaporation region absorbs the solar energy and converts it to heat, which is then carried by the heat transfer medium to the heating tube.

  15. Photovoltaic solar concentrator

    Energy Technology Data Exchange (ETDEWEB)

    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.

  16. 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.

  17. Photovoltaic solar concentrator

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-12-11

    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.

  18. Photovoltaic solar concentrator

    Science.gov (United States)

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

    2012-12-11

    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.

  19. 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

  20. Solar radiation absorption in solar ponds

    Energy Technology Data Exchange (ETDEWEB)

    Cengel, Y.A.; Ozisik, M.N.

    1984-01-01

    The local rate of absorption of the solar radiation in a solar pond is determined for the direct component at angles of incidence from 0/sup 0/ to 75/sup 0/ with 15/sup 0/ intervals as well as for the diffuse component by the exact treatment of the radiation problem. The effects of bottom reflection, the pond depth, the type of radiation on the thermal performance of the pond are examined, and a new rigorous approach is presented for treating diffuse radiation as a direct beam. The fraction of the solar radiation absorbed within the first 10 cm of water is determined under various conditions. The local rate of solar energy absorption at any depth and at any incidence angle can readily be computed from a fourthdegree polynomial expression, the coefficients of which are tabulated for different incidence angles and bottom reflectivities.

  1. 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 

  2. Solar irradiance, total and spectral; Irradiancia solar, total e espectral

    Energy Technology Data Exchange (ETDEWEB)

    Fraidenraich, Naum [Pernambuco Univ., Recife, PE (Brazil). Centro de Energia Nuclear; Lyra, Francisco [Companhia Hidroeletrica do Sao Francisco (CHESF), Recife, PE (Brazil)

    1995-12-31

    In this chapter some important characteristics concerning solar irradiance are presented, such as: solar constant; spectral irradiance for a zeroed mass of air; solar constant variation according to Earth-Sun distance; solar energy variation on Earth`s surface; atmospheric attenuation of solar energy; and total radiation and spectral irradiation on Earth`s surface. 3 refs., 5 figs., 6 tabs.

  3. 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

  4. Solar Cycle 24 and the Solar Dynamo

    Science.gov (United States)

    Pesnell, W. D.; Schatten, K.

    2007-01-01

    We will discuss the polar field precursor method for solar activity prediction, which predicts cycle 24 will be significantly lower than recent activity cycles, and some new ideas rejuvenating Babcock's shallow surface dynamo. The polar field precursor method is based on Babcock and Leighton's dynamo models wherein the polar field at solar minimum plays a major role in generating the next cycle's toroidal field and sunspots. Thus, by examining the polar fields of the Sun near solar minimum, a forecast for the next cycle's activity is obtained. With the current low value for the Sun's polar fields, this method predicts solar cycle 24 will be one of the lowest in recent times, with smoothed F10.7 radio flux values peaking near 135 plus or minus 35 (2 sigma), in the 2012-2013 timeframe (equivalent to smoothed Rz near 80 plus or minus 35 [2 sigma]). One may have to consider solar activity as far back as the early 20th century to find a cycle of comparable magnitude. We discuss unusual behavior in the Sun's polar fields that support this prediction. Normally, the solar precursor method is consistent with the geomagnetic precursor method, wherein geomagnetic variations are thought to be a good measure of the Sun's polar field strength. Because of the unusual polar field, the Earth does not appear to be currently bathed in the Sun's extended polar field (the interplanetary field), hence negating the primal cause behind the geomagnetic precursor technique. We also discuss how percolation may support Babcock's original shallow solar dynamo. In this process ephemeral regions from the solar magnetic carpet, guided by shallow surface fields, may collect to form pores and sunspots.

  5. 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.

  6. SOLAR EFFECTS ON BUILDING DESIGN.

    Science.gov (United States)

    Building Research Inst., Inc., Washington, DC.

    A REPORT OF A PROGRAM HELD AS PART OF THE BUILDING RESEARCH INSTITUTE 1962 SPRING CONFERENCE ON THE SOLAR EFFECTS ON BUILDING DESIGN. TOPICS DISCUSSED ARE--(1) SOLAR ENERGY DATA APPLICABLE TO BUILDING DESIGN, (2) THERMAL EFFECTS OF SOLAR RADIATION ON MAN, (3) SOLAR EFFECTS ON ARCHITECTURE, (4) SOLAR EFFECTS ON BUILDING COSTS, (5) SELECTION OF…

  7. 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…

  8. Climate Fundamentals for Solar Heating.

    Science.gov (United States)

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

    The design of any solar heating system is influenced heavily by climate; in this bulletin, information on climate as related to solar heating is as related to solar heating is provided. Topics discussed include: (1) solar radiation; (2) degree days; (3) climate and calculations which make use of solar radiation and degree days; and (4)…

  9. 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.

  10. The Solar Cycle

    CERN Document Server

    Hathaway, David H

    2015-01-01

    The Solar Cycle is reviewed. The 11-year cycle of solar activity is characterized by the rise and fall in the numbers and surface area of sunspots. A number of other solar activity indicators also vary in association with the sunspots including; the 10.7cm radio flux, the total solar irradiance, the magnetic field, flares and coronal mass ejections, geomagnetic activity, galactic cosmic ray fluxes, and radioisotopes in tree rings and ice cores. Individual solar cycles are characterized by their maxima and minima, cycle periods and amplitudes, cycle shape, the equatorward drift of the active latitudes, hemispheric asymmetries, and active longitudes. Cycle-to-cycle variability includes the Maunder Minimum, the Gleissberg Cycle, and the Gnevyshev-Ohl (even-odd) Rule. Short-term variability includes the 154-day periodicity, quasi-biennial variations, and double-peaked maxima. We conclude with an examination of prediction techniques for the solar cycle and a closer look at cycles 23 and 24.

  11. The Solar Cycle.

    Science.gov (United States)

    Hathaway, David H

    The solar cycle is reviewed. The 11-year cycle of solar activity is characterized by the rise and fall in the numbers and surface area of sunspots. A number of other solar activity indicators also vary in association with the sunspots including; the 10.7 cm radio flux, the total solar irradiance, the magnetic field, flares and coronal mass ejections, geomagnetic activity, galactic cosmic ray fluxes, and radioisotopes in tree rings and ice cores. Individual solar cycles are characterized by their maxima and minima, cycle periods and amplitudes, cycle shape, the equatorward drift of the active latitudes, hemispheric asymmetries, and active longitudes. Cycle-to-cycle variability includes the Maunder Minimum, the Gleissberg Cycle, and the Gnevyshev-Ohl (even-odd) Rule. Short-term variability includes the 154-day periodicity, quasi-biennial variations, and double-peaked maxima. We conclude with an examination of prediction techniques for the solar cycle and a closer look at cycles 23 and 24.

  12. Solar Asset Management Software

    Energy Technology Data Exchange (ETDEWEB)

    Iverson, Aaron [Ra Power Management, Inc., Oakland, CA (United States); Zviagin, George [Ra Power Management, Inc., Oakland, CA (United States)

    2016-09-30

    Ra Power Management (RPM) has developed a cloud based software platform that manages the financial and operational functions of third party financed solar projects throughout their lifecycle. RPM’s software streamlines and automates the sales, financing, and management of a portfolio of solar assets. The software helps solar developers automate the most difficult aspects of asset management, leading to increased transparency, efficiency, and reduction in human error. More importantly, our platform will help developers save money by improving their operating margins.

  13. Solar energy emplacement developer

    Science.gov (United States)

    Mortensen, Michael; Sauls, Bob

    1991-01-01

    A preliminary design was developed for a Lunar Power System (LPS) composed of photovoltaic arrays and microwave reflectors fabricated from lunar materials. The LPS will collect solar energy on the surface of the Moon, transform it into microwave energy, and beam it back to Earth where it will be converted into usable energy. The Solar Energy Emplacement Developer (SEED) proposed will use a similar sort of solar energy collection and dispersement to power the systems that will construct the LPS.

  14. Horizontally mounted solar collector

    Science.gov (United States)

    Black, D. H. (Inventor)

    1979-01-01

    Solar energy is collected by using a vertical deflector assembly, a stationary reflector and a horizontally mounted solar collector. The deflector assembly contains a plurality of vanes which change the direction of the solar energy to the vertical, while constantly keeping the same side of the deflector facing the sun. The vertical rays are then reflected off the stationary reflector and are then absorbed by the collector.

  15. THE THERMOELECTRIC SOLAR PANELS

    OpenAIRE

    R. Ahiska; Nykyruy, L. I.; Omer, G.; G. D. Mateik

    2016-01-01

    In this study, load characteristics of thermoelectric and photovoltaic solar panels are investigated and compared with each other with experiments. Thermoelectric solar panels converts the heat generated by sun directly to electricity; while, photovoltaic solar pales converts photonic energy from sun to electricity. In both types, maximum power can be obtained when the load resistance is equal to internal resistance. According to experimental results, power generated from unit surface with th...

  16. Solar Neutrino Data, Solar Model Uncertainties and Neutrino Oscillations

    CERN Document Server

    Krauss, L M; White, M; Krauss, Lawrence M.; Gates, Evalyn; White, Martin

    1993-01-01

    We incorporate all existing solar neutrino flux measurements and take solar model flux uncertainties into account in deriving global fits to parameter space for the MSW and vacuum solutions of the solar neutrino problem.

  17. Solar Neutrino Data, Solar Model Uncertainties and Neutrino Oscillations

    OpenAIRE

    1992-01-01

    We incorporate all existing solar neutrino flux measurements and take solar model flux uncertainties into account in deriving global fits to parameter space for the MSW and vacuum solutions of the solar neutrino problem.

  18. 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).

  19. Long Island Solar Farm

    Energy Technology Data Exchange (ETDEWEB)

    Anders, R.

    2013-05-01

    The Long Island Solar Farm (LISF) is a remarkable success story, whereby very different interest groups found a way to capitalize on unusual circumstances to develop a mutually beneficial source of renewable energy. The uniqueness of the circumstances that were necessary to develop the Long Island Solar Farm make it very difficult to replicate. The project is, however, an unparalleled resource for solar energy research, which will greatly inform large-scale PV solar development in the East. Lastly, the LISF is a superb model for the process by which the project developed and the innovation and leadership shown by the different players.

  20. 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

  1. 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

  2. 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 stratifica...... 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...

  3. 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

  4. 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...

  5. Solar Cooker Technological Change

    DEFF Research Database (Denmark)

    Ahmad, Bashir

    1997-01-01

    The challenges which solar cooking technology is facing right now is discussed. Based on a field study in Madras and Gujarat, it is asserted that there is an important incompatibility between the technology and the every day real-life conditions of the "users" of solar cooker. An evaluation report...... on a solar cooker technology in Burkina Faso supports the findings of the study. It is concluded that the users and other important actors have to be incorporated in the technological development process of solar cookers in the future....

  6. Solar Cycle Predictions

    Science.gov (United States)

    Pesnell, William Dean

    2012-01-01

    Solar cycle predictions are needed to plan long-term space missions; just like weather predictions are needed to plan the launch. Fleets of satellites circle the Earth collecting many types of science data, protecting astronauts, and relaying information. All of these satellites are sensitive at some level to solar cycle effects. Predictions of drag on LEO spacecraft are one of the most important. Launching a satellite with less propellant can mean a higher orbit, but unanticipated solar activity and increased drag can make that a Pyrrhic victory as you consume the reduced propellant load more rapidly. Energetic events at the Sun can produce crippling radiation storms that endanger all assets in space. Solar cycle predictions also anticipate the shortwave emissions that cause degradation of solar panels. Testing solar dynamo theories by quantitative predictions of what will happen in 5-20 years is the next arena for solar cycle predictions. A summary and analysis of 75 predictions of the amplitude of the upcoming Solar Cycle 24 is presented. The current state of solar cycle predictions and some anticipations how those predictions could be made more accurate in the future will be discussed.

  7. 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.

  8. Solar Tracking System

    OpenAIRE

    Nguyen, Nam

    2016-01-01

    The goal of this thesis was to develop a laboratory prototype of a solar tracking system, which is able to enhance the performance of the photovoltaic modules in a solar energy system. The operating principle of the device is to keep the photovoltaic modules constantly aligned with the sunbeams, which maximises the exposure of solar panel to the Sun’s radiation. As a result, more output power can be produced by the solar panel. The work of the project included hardware design and implemen...

  9. Solar Hydrogen Reaching Maturity

    Directory of Open Access Journals (Sweden)

    Rongé Jan

    2015-09-01

    Full Text Available Increasingly vast research efforts are devoted to the development of materials and processes for solar hydrogen production by light-driven dissociation of water into oxygen and hydrogen. Storage of solar energy in chemical bonds resolves the issues associated with the intermittent nature of sunlight, by decoupling energy generation and consumption. This paper investigates recent advances and prospects in solar hydrogen processes that are reaching market readiness. Future energy scenarios involving solar hydrogen are proposed and a case is made for systems producing hydrogen from water vapor present in air, supported by advanced modeling.

  10. Solar Tracking System

    OpenAIRE

    Nguyen, Nam

    2016-01-01

    The goal of this thesis was to develop a laboratory prototype of a solar tracking system, which is able to enhance the performance of the photovoltaic modules in a solar energy system. The operating principle of the device is to keep the photovoltaic modules constantly aligned with the sunbeams, which maximises the exposure of solar panel to the Sun’s radiation. As a result, more output power can be produced by the solar panel. The work of the project included hardware design and implemen...

  11. 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.

  12. Make Your Own Solar Panel.

    Science.gov (United States)

    Suzuki, David

    1992-01-01

    Presents an activity in which students make a simulated solar panel to learn about the principles behind energy production using solar panels. Provides information about how solar panels function to produce energy. (MCO)

  13. Make Your Own Solar Panel.

    Science.gov (United States)

    Suzuki, David

    1992-01-01

    Presents an activity in which students make a simulated solar panel to learn about the principles behind energy production using solar panels. Provides information about how solar panels function to produce energy. (MCO)

  14. Surface Meteorology and Solar Energy

    Data.gov (United States)

    National Aeronautics and Space Administration — Surface Meteorology and Solar Energy data - over 200 satellite-derived meteorology and solar energy parameters, monthly averaged from 22 years of data, global solar...

  15. Astroparticle physics with solar neutrinos

    OpenAIRE

    2011-01-01

    Solar neutrino experiments observed fluxes smaller than the expectations from the standard solar model. This discrepancy is known as the “solar neutrino problem”. Flux measurements by Super-Kamiokande and SNO have demonstrated that the solar neutrino problem is due to neutrino oscillations. Combining the results of all solar neutrino experiments, parameters for solar neutrino oscillations are obtained. Correcting for the effect of neutrino oscillations, the observed neutrino fluxes are consis...

  16. Solar ponds: a selected bibliography

    Energy Technology Data Exchange (ETDEWEB)

    1981-11-01

    This bibliography contains citations on: regular solar ponds; shallow solar ponds; and patents. Certain references are specifically recommended. The data bases searched for the bibliography are listed. (LEW)

  17. Future: Solar energy. Zukunft: Sonnenenergie

    Energy Technology Data Exchange (ETDEWEB)

    Lange, V.

    1987-01-01

    The first chapter, 'Solar energy - more than just Utopia' deals with the following: Alternatives to nuclear energy problems of energy supply, solar energy use, commencement of the solar age in space, solar technology in the Federal Republic of Germany, solar collectors, wind power, energy from hydrogen. The second chapter 'Solar energy - its contribution to future energy supply' discusses prospects for the future (interviews with scientists and engineers). The third and last chapter gives practical hints (solar energy use: self-construction of solar plants). (HWJ).

  18. Solar Irradiance Variability

    CERN Document Server

    Solanki, Sami K

    2012-01-01

    The Sun has long been considered a constant star, to the extent that its total irradiance was termed the solar constant. It required radiometers in space to detect the small variations in solar irradiance on timescales of the solar rotation and the solar cycle. A part of the difficulty is that there are no other constant natural daytime sources to which the Sun's brightness can be compared. The discovery of solar irradiance variability rekindled a long-running discussion on how strongly the Sun affects our climate. A non-negligible influence is suggested by correlation studies between solar variability and climate indicators. The mechanism for solar irradiance variations that fits the observations best is that magnetic features at the solar surface, i.e. sunspots, faculae and the magnetic network, are responsible for almost all variations (although on short timescales convection and p-mode oscillations also contribute). In spite of significant progress important questions are still open. Thus there is a debat...

  19. Solar Energy: Heat Transfer.

    Science.gov (United States)

    Knapp, Henry H., III

    This module on heat transfer is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy technologies. The…

  20. Solar Energy: Heat Storage.

    Science.gov (United States)

    Knapp, Henry H., III

    This module on heat storage is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy technologies. The module…

  1. Solar Energy: Home Heating.

    Science.gov (United States)

    Knapp, Henry H., III

    This module on home heating is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy technologies. The module…

  2. Solar insolation model

    Science.gov (United States)

    Smith, J. H.

    1980-01-01

    Computer program SOLINS helps engineers with relatively complex task of choosing best orientation of fixed flat-plate solar collectors for local conditions. Program models average hourly solar insolation on fixed but arbitrarily-oriented surface. Consideration is given to problems of array spacing, shadowing, and use of augmentation reflectors to increase insolation at collector surface.

  3. Solar array deployment mechanism

    Science.gov (United States)

    Calassa, Mark C.; Kackley, Russell

    1995-05-01

    This paper describes a Solar Array Deployment Mechanism (SADM) used to deploy a rigid solar array panel on a commercial spacecraft. The application required a deployment mechanism design that was not only lightweight, but also could be produced and installed at the lowest possible cost. This paper covers design, test, and analysis of a mechanism that meets these requirements.

  4. Solar absorption cooling

    NARCIS (Netherlands)

    Kim, D.-S.

    2007-01-01

    As the world concerns more and more on global climate changes and depleting energy resources, solar cooling technology receives increasing interests from the public as an environment-friendly and sustainable alternative. However, making a competitive solar cooling machine for the market still

  5. Solar '77

    Energy Technology Data Exchange (ETDEWEB)

    Wenzel, G

    1978-06-01

    This manual was designed to give everyone a basic understanding of necessary conservation and system features for an efficient, cost effective, and comfortable solar tempered dwelling. Primary emphasis was given to energy efficient design features and construction in new and existing dwellings. A solar glossary is included. (MHR)

  6. Solar energy in Czechoslovakia

    OpenAIRE

    Lindberg, Eva

    1990-01-01

    The purpose of my tour to Czechoslovakia was to participate the Third International Conference Applied Optics in Solar Energy, which was held in Prague, Octoher 2-6, 1989, and then visit some scientific institutes and solar collector plants as guest of the Czechoslovakian Academy of Science. This was made possihle hy an exchange researcher grant from the Royal Swedish Academy of Engineering Sciences.

  7. Leaves: Nature's Solar Collectors

    Science.gov (United States)

    Isabelle, Aaron D.; de Groot, Cornelis

    2009-01-01

    One of the most captivating things about plants is the way they capture the Sun's energy, but this can be a difficult topic to cover with elementary students. Therefore, to help students to make a concrete connection to this abstract concept, this series of solar-energy lessons focuses on leaves and how they act as "solar collectors." As students…

  8. Solar absorption cooling

    NARCIS (Netherlands)

    Kim, D.-S.

    2007-01-01

    As the world concerns more and more on global climate changes and depleting energy resources, solar cooling technology receives increasing interests from the public as an environment-friendly and sustainable alternative. However, making a competitive solar cooling machine for the market still remain

  9. Solar Electricity for Homes

    Science.gov (United States)

    Roman, Harry T.

    2012-01-01

    Every day, the sun showers the Earth with millions of times more energy than its people use. The only problem is that energy is spread out over the entire Earth's surface and must be harvested. Engineers are learning to capture and use some of this energy to make electricity for homes. Solar panels make up the heart of a solar system. They can be…

  10. The lower solar atmosphere

    NARCIS (Netherlands)

    Rutten, R.J.

    2001-01-01

    This "rapporteur" report discusses the solar photosphere and low chromosphere in the context of chemical composition studies. The highly dynamical nature of the photosphere does not seem to jeopardize precise determination of solar abundances in classical fashion. It is still an open question how th

  11. Future Solar Neutrino Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Y. [Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Higashi-Mozumi, Kamioka-cho, Hida-city, 506-1205 (Japan)]. E-mail: suzuki@suketto.icrr.u-tokyo.ac.jp

    2005-06-15

    The purpose of the future solar neutrino experiments is briefly reviewed. The future experimental programs which aim to measure the low energy solar neutrinos are described. We do not cover all the projects. Experiments using noble gases are promising for the pp-neutrino measurements.

  12. 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....

  13. Mexican Virtual Solar Observatory

    Science.gov (United States)

    Santillan, A.; Hernandez-Cervantes, L.; Gonzalez-Ponce, A.; Hill, F.; Blanco-Cano, X.

    2007-12-01

    The Virtual Solar Observatory (VSO) concept contains software tools for searching, manipulating, and analyzing data from archives of solar data at many different observatories around the world (Hill 2000). The VSO not only provides fast and reliable access to the existing solar data, but also represents a powerful and unique machinery to perform numerical simulations for the evolution of a variety of different phenomena associated with solar activity. Two Mexican Universities, Universidad Nacional Autónoma de México and the Universidad de Sonora, are working together to create the Mexican Virtual Solar Observatory (MVSO) that will be part of a wider National effort. In this work we present a general description of the MVSO project, as well as the advances obtained in the development of Graphical User Interfaces (GUI) to Remotely Perform Numerical Simulation of the Evolution of Coronal Mass Ejection in the Interplanetary Medium.

  14. Solar wind travel time

    Science.gov (United States)

    Russell, C. T.

    A useful rule of thumb in solar terrestrial studies is that the solar wind travels 4 Earth radii (RE) per minute. Long-term studies of solar wind velocity [e.g., Luhmann et al., 1993; 1994] show that the median velocity is about 420 km/s, corresponding to 3.96 RE min-1. The quartiles are about 370 km/s and 495 km/s, corresponding to 3.48 Re min-1 and 4.66 Re min-1 respectively. This number helps estimate the delays expected when observing a discontinuity at a solar wind monitor; one example is ISEE-3 when it was at the forward libration point (about 60 min). It is also helpful for estimating how much time passes before the dayside magnetosphere is compressed as denser solar wind flows by (about 2.5 min).

  15. Initial performance tests of SLATS photovoltaic concentrator modules

    Science.gov (United States)

    Stern, Theodore G.

    Tests have been performed to determine the terrestrial conversion efficiency and operating temperature in space of a modular photovoltaic concentrator. Nine test modules were fabricated, each having a set of three mirrors mounted in a graphite composite frame. Each mirror was mechanically formed by beryllium-copper sheet stock into an offset parabolic cylinder. An active photovoltaic receiver, comprising two strings of three parallel-connected gallium arsenide cells, was mounted on the central portion of the middle mirror in each module. Tests performed under terrestrial illumination (AM1.5) indicated mean mirror-cell conversion efficiency of 16.4 percent for silvered mirrors and 14 percent for aluminized mirrors at a 50 C cell temperature. Tests performed in a liquid-nitrogen shrouded vacuum chamber indicated a cell operating temperature of 90 C, which corresponds well to the results of independent thermal analysis. On the basis of these data, the performance of kilowatt-sized units in space using beryllium-copper mirrors is projected to be 35 W/kg. By substituting aluminum substrates for copper, a specific power of up to 55 W/kg is achievable in this configuration.

  16. Solar heating and cooling.

    Science.gov (United States)

    Duffie, J A; Beckman, W A

    1976-01-16

    We have adequate theory and engineering capability to design, install, and use equipment for solar space and water heating. Energy can be delivered at costs that are competitive now with such high-cost energy sources as much fuel-generated, electrical resistance heating. The technology of heating is being improved through collector developments, improved materials, and studies of new ways to carry out the heating processes. Solar cooling is still in the experimental stage. Relatively few experiments have yielded information on solar operation of absorption coolers, on use of night sky radiation in locations with clear skies, on the combination of a solar-operated Rankine engine and a compression cooler, and on open cycle, humidification-dehumidification systems. Many more possibilities for exploration exist. Solar cooling may benefit from collector developments that permit energy delivery at higher temperatures and thus solar operation of additional kinds of cycles. Improved solar cooling capability can open up new applications of solar energy, particularly for larger buildings, and can result in markets for retrofitting existing buildings. Solar energy for buildings can, in the next decade, make a significant contribution to the national energy economy and to the pocketbooks of many individual users. very large-aggregate enterprises in manufacture, sale, and installation of solar energy equipment can result, which can involve a spectrum of large and small businesses. In our view, the technology is here or will soon be at hand; thus the basic decisions as to whether the United States uses this resource will be political in nature.

  17. Delft's solar car wins Solar Challenge 2003

    NARCIS (Netherlands)

    Van Kasteren, J.

    2003-01-01

    There were remarkable scenes in Adelaide, Australia,on the afternoon of Wednesday 22 October 2003 when a swathe of orange spilled through the city. Barely visible at the heart of this burst of colour was the Nuna II, a futuristic vehicle which had just won the Solar Challenge 2003, a four-day journe

  18. Solar architecture and solar construction; Solararchitektur und Solares Bauen

    Energy Technology Data Exchange (ETDEWEB)

    Karweger, A. [Economic Forum Ltd., London (United Kingdom)]|[Economic Forum Ltd., Muenchen (Germany)]|[Economic Forum Ltd., Bozen (Italy)

    2008-07-01

    Solar architecture already takes into account solar energy during the design phase: The generation and use of energy as well as the materials for thermal energy storage characterize the planning process from the beginning. Solar houses are already technically feasible since a long time and become more and more interesting in economic respect due to continuously increasing energy prices. However this knowledge is not reflected in the construction practice. Energy-efficient construction is very often understood as a compact, thermally-insulated construction body, which has a small enveloping surface with small windows (principle Thermos bottle). The credo of the architects ''the form follows the task'' is converted into the opposite. The energy concept of a house must take into account its specific location and situation (climate). A uniform building envelope for all building types, locations and uses does not exist. A comprehensive planning and a cross-field dialogue between all participants is necessary in order to develop an comprehensive energy concept for a certain building; Supporting framework, heating, ventilation, construction physics and facade must be considered in dependance of each other. This is the only way to predict future heating and cooling performance and to optimize heating and ventilation plants. (orig.)

  19. Solar Energetic Particles

    Science.gov (United States)

    Király, Péter

    Energetic particles recorded in the Earth environment and in interplanetary space have a multitude of origins, i.e. acceleration and propagation histories. At early days practically all sufficiently energetic particles were considered to have come either from solar flares or from interstellar space. Later on, co-rotating interplanetary shocks, the termination shock of the supersonic solar wind, planetary bow shocks and magnetospheres, and also coronal mass ejections (CME) were recognized as energetic particle sources. It was also recognized that less energetic (suprathermal) particles of solar origin and pick-up ions have also a vital role in giving rise to energetic particles in interplanetary disturbances. The meaning of the term "solar energetic particles" (SEP) is now somewhat vague, but essentially it refers to particles produced in disturbances fairly directly related to solar processes. Variation of intensity fluctuations with energy and with the phase of the solar cycle will be discussed. Particular attention will be given to extremes of time variation, i.e. to very quiet periods and to large events. While quiet-time fluxes are expected to shed light on some basic coronal processes, large events dominate the fluctuation characteristics of cumulated fluence, and the change of that fluctuation with energy and with the phase of the solar cycle may also provide important clues. Mainly ISEE-3 and long-term IMP-8 data will be invoked. Energetic and suprathermal particles that may never escape into interplanetary space may play an important part in heating the corona of the sun.

  20. Solar Hot Water Heater

    Science.gov (United States)

    1978-01-01

    The solar panels pictured below, mounted on a Moscow, Idaho home, are part of a domestic hot water heating system capable of providing up to 100 percent of home or small business hot water needs. Produced by Lennox Industries Inc., Marshalltown, Iowa, the panels are commercial versions of a collector co-developed by NASA. In an effort to conserve energy, NASA has installed solar collectors at a number of its own facilities and is conducting research to develop the most efficient systems. Lewis Research Center teamed with Honeywell Inc., Minneapolis, Minnesota to develop the flat plate collector shown. Key to the collector's efficiency is black chrome coating on the plate developed for use on spacecraft solar cells, the coating prevents sun heat from "reradiating," or escaping outward. The design proved the most effective heat absorber among 23 different types of collectors evaluated in a Lewis test program. The Lennox solar domestic hot water heating system has three main components: the array of collectors, a "solar module" (blue unit pictured) and a conventional water heater. A fluid-ethylene glycol and water-is circulated through the collectors to absorb solar heat. The fluid is then piped to a double-walled jacket around a water tank within the solar module.

  1. CHOOSING SOLAR PHOTOVOLTAIC PLANT

    Directory of Open Access Journals (Sweden)

    Vinnikov A. V.

    2015-04-01

    Full Text Available Promising is the direction and, above all, in matters of energy saving and energy efficiency of Autonomous systems of power supply, the use of renewable sources-newable energy as a major source of energy for consumers in remote areas. Here priority is given to solar energy. Since solar radiation can be change place not only in heat and electrical. The article contains three main structural schematics of electricity supply with solar power plants. The features of their work are disclosed, as well as an algorithm for calculating solar energy systems, the sequence of which is to define the required parameters, the daily energy consumption by consumers of electric power, the calculation capacity of the battery, the choice of the inverter and determining the area of solar batteries. The article reveals the conditions that affect the calculation of the PV system. It is shown that the greatest efficiency, including economic and reliability we have at combined (hybrid Autonomous system, which was carried out with both solar power and wind power and gas stations. The important matters of improving the reliability of solar systems are the introduction to the design of a new element of the base, and first and foremost, Autonomous inventors performed on a single-phase transformer with a rotating magnetic field

  2. Analysis of Flat-Plate Solar Array and Solar Lantern

    Directory of Open Access Journals (Sweden)

    P. L. N. V. Aashrith

    2014-05-01

    Full Text Available A very detailed theortical analysis of a solar array has been carried out based on established values of solar radiation data to predict the performance of solar lamp . The analysis is based on established theory about flat-plate collectors. Top heat loss coefficient (Ut, Bottom heat loss coefficient (Ub, Overall heat loss coefficient (Ul, Useful energy (Qu, efficiency (hp of the flat-plate solar array and efficiency (hl of the solar lantern has been calculated.

  3. Relativistic implications of solar astrometry

    CERN Document Server

    Sigismondi, Costantino

    2011-01-01

    The modern methods of measurement of the solar diameter and oblateness are reviewed. Either ground-based or balloon-borne and satellite measurements are considered. The importance of solar astrometry for General Relativity is emphasized, particularly attention is given to the solar oblateness problem, as well as the studies of solar astrophysics to the whole world of physics from nucleosynthesis to neutrinos.

  4. Solar Hidden Photon Search

    CERN Document Server

    Schwarz, Matthias; Redondo, Javier; Ringwald, Andreas; Wiedemann, Guenter

    2011-01-01

    The Solar Hidden Photon Search (SHIPS) is a joint astroparticle project of the Hamburger Sternwarte and DESY. The main target is to detect the solar emission of a new species of particles, so called Hidden Photons (HPs). Due to kinetic mixing, photons and HPs can convert into each other as they propagate. A small number of solar HPs - originating from photon to HP oscillations in the interior of the Sun - can be converted into photons in a long vacuum pipe pointing to the Sun - the SHIPS helioscope.

  5. Solar Hidden Photon Search

    Energy Technology Data Exchange (ETDEWEB)

    Schwarz, Matthias; Wiedemann, Guenter [Hamburg Univ. (Germany). Sternwarte; Lindner, Axel; Ringwald, Andreas [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Redondo, Javier [Max-Planck-Institut fuer Physik und Astrophysik, Muenchen (Germany)

    2011-11-15

    The Solar Hidden Photon Search (SHIPS) is a joint astroparticle project of the Hamburger Sternwarte and DESY. The main target is to detect the solar emission of a new species of particles, so called Hidden Photons (HPs). Due to kinetic mixing, photons and HPs can convert into each other as they propagate. A small number of solar HPs - originating from photon to HP oscillations in the interior of the Sun - can be converted into photons in a long vacuum pipe pointing to the Sun - the SHIPS helioscope. (orig.)

  6. Solar flares. [plasma physics

    Science.gov (United States)

    Rust, D. M.

    1979-01-01

    The present paper deals with explosions in a magnetized solar plasma, known as flares, whose effects are seen throughout the electromagnetic spectrum, from gamma-rays through the visible and to the radio band. The diverse phenomena associated with flares are discussed, along with the physical mechanisms that have been advanced to explain them. The impact of solar flare research on the development of plasma physics and magnetohydrodynamics is noted. The rapid development of solar flare research during the past 20 years, owing to the availability of high-resolution images, detailed magnetic field measurements, and improved spectral data, is illustrated.

  7. Quantum dot solar cells

    CERN Document Server

    Wu, Jiang

    2013-01-01

    The third generation of solar cells includes those based on semiconductor quantum dots. This sophisticated technology applies nanotechnology and quantum mechanics theory to enhance the performance of ordinary solar cells. Although a practical application of quantum dot solar cells has yet to be achieved, a large number of theoretical calculations and experimental studies have confirmed the potential for meeting the requirement for ultra-high conversion efficiency. In this book, high-profile scientists have contributed tutorial chapters that outline the methods used in and the results of variou

  8. Infrared Solar Physics

    Directory of Open Access Journals (Sweden)

    Matthew J. Penn

    2014-05-01

    Full Text Available The infrared solar spectrum contains a wealth of physical data about our Sun, and is explored using modern detectors and technology with new ground-based solar telescopes. The scientific motivation behind exploring these wavelengths is presented, along with a brief look at the rich history of observations here. Several avenues of solar physics research exploiting and benefiting from observations at infrared wavelengths from roughly 1000 nm to 12 400 nm are discussed, and the instrument and detector technology driving this research is briefly summarized. Finally, goals for future work at infrared wavelengths are presented in conjunction with ground and space-based observations.

  9. Physics of solar energy

    CERN Document Server

    Chen, C Julian

    2011-01-01

    The definitive guide to the science of solar energy You hold in your hands the first, and only, truly comprehensive guide to the most abundant and most promising source of alternative energy-solar power. In recent years, all major countries in the world have been calling for an energy revolution. The renewable energy industry will drive a vigorous expansion of the global economy and create more ""green"" jobs. The use of fossil fuels to power our way of living is moving toward an inevitable end, with sources of coal, petroleum, and natural gas being fiercely depleted. Solar energy

  10. Dye sensitized solar cells.

    Science.gov (United States)

    Wei, Di

    2010-03-16

    Dye sensitized solar cell (DSSC) is the only solar cell that can offer both the flexibility and transparency. Its efficiency is comparable to amorphous silicon solar cells but with a much lower cost. This review not only covers the fundamentals of DSSC but also the related cutting-edge research and its development for industrial applications. Most recent research topics on DSSC, for example, applications of nanostructured TiO(2), ZnO electrodes, ionic liquid electrolytes, carbon nanotubes, graphene and solid state DSSC have all been included and discussed.

  11. Dye Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Di Wei

    2010-03-01

    Full Text Available Dye sensitized solar cell (DSSC is the only solar cell that can offer both the flexibility and transparency. Its efficiency is comparable to amorphous silicon solar cells but with a much lower cost. This review not only covers the fundamentals of DSSC but also the related cutting-edge research and its development for industrial applications. Most recent research topics on DSSC, for example, applications of nanostructured TiO2, ZnO electrodes, ionic liquid electrolytes, carbon nanotubes, graphene and solid state DSSC have all been included and discussed.

  12. Solar Environmental Disturbances

    Science.gov (United States)

    2007-11-02

    34La Sapienza", Rome, Italy , Jan 03 – Jan 04. Dr. S. James Tappin, Univ. of Birmingham (UK), 16-22 Aug 2005 WOS visit sponsored by EOARD...SOLAR TELESCOPE Dr. Alessandro Cacciani of the University "La Sapienza" of Rome, Italy , spent a year here as a Senior NRC Associate funded by AFOSR...DiMartino, V. 2004, Solar Phys. 220, 317-331: Seismology of the Solar Atmosphere (attributed by Cacciani to residence at NSO/SP as an AF NRC Associate

  13. Exploring the solar system

    CERN Document Server

    Bond, Peter

    2012-01-01

    The exploration of our solar system is one of humanity's greatest scientific achievements. The last fifty years in particular have seen huge steps forward in our understanding of the planets, the sun, and other objects in the solar system. Whilst planetary science is now a mature discipline - involving geoscientists, astronomers, physicists, and others - many profound mysteries remain, and there is indeed still the tantalizing possibility that we may find evidence of life on another planet in our system.Drawing upon the latest results from the second golden age of Solar System exploration, aut

  14. 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.

  15. 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.

  16. 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

  17. Concentrating Solar Power

    Energy Technology Data Exchange (ETDEWEB)

    Weinstein, Lee A.; Loomis, James; Bhatia, Bikram; Bierman, David M.; Wang, Evelyn N.; Chen, Gang

    2015-12-09

    Solar energy is a bountiful renewable energy resource: the energy in the sunlight that reaches Earth in an hour exceeds the energy consumed by all of humanity in a year.(1) While the phrase “solar energy conversion” probably brings photovoltaic (PV) cells to mind first, PV is not the only option for generating electricity from sunlight. Another promising technology for solar energy conversion is solar–thermal conversion, commonly referred to as concentrating solar power (CSP).(2) The first utility-scale CSP plants were constructed in the 1980s, but in the two decades that followed, CSP saw little expansion.(3, 4) More recent years, however, have seen a CSP renaissance due to unprecedented growth in the adoption of CSP.(3, 5) Photographs of two operating CSP plants, a parabolic trough collector plant and a central receiver (or “power tower”), are shown here.

  18. Solar Indices Bulletin

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Solar Indices Bulletin is a prompt monthly information product that is distributed within two weeks after the observation month closes. For the month just ended,...

  19. Solar cooperatives; Genosse Sonne

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Dierk

    2010-06-15

    Not a boom but a trend: Increasingly, solar power plants and other renewables-based systems are financed by cooperatives. This organizational structure requires long-term strategies and some idealism. (orig.)

  20. Solar neutrino oscillation phenomenology

    Indian Academy of Sciences (India)

    Srubabati Goswami

    2004-02-01

    This article summarises the status of the solar neutrino oscillation phenomenology at the end of 2002 in the light of the SNO and KamLAND results. We first present the allowed areas obtained from global solar analysis and demonstrate the preference of the solar data towards the large-mixing-angle (LMA) MSW solution. A clear confirmation in favour of the LMA solution comes from the KamLAND reactor neutrino data. the KamLAND spectral data in conjunction with the global solar data further narrows down the allowed LMA region and splits it into two allowed zones - a low $ m^{2}$ region (low-LMA) and high $ m^{2}$ region (high-LMA). We demonstrate through a projected analysis that with an exposure of 3 kton-year (kTy) KamLAND can remove this ambiguity.

  1. Photovoltaic solar cell

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-05-20

    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 electricity 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.

  2. Solar energy policy review

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-08-17

    A number of memoranda and reports are collected which deal with evaluations of solar energy policy options, including direct and indirect labor impacts and costs of different options and consumer protection. (LEW)

  3. The Solar Dynamo Zoo

    Science.gov (United States)

    Egeland, Ricky; Soon, Willie H.; Baliunas, Sallie L.; Hall, Jeffrey C.; Pevtsov, Alexei A.; Henry, Gregory W.

    2016-05-01

    We present composite time series of Ca II H & K line core emission indices of up to 50 years in length for a set of 27 solar-analog stars (spectral types G0-G5; within ~10% of the solar mass) and the Sun. These unique data are available thanks to the long-term dedicated efforts of the Mount Wilson Observatory HK project, the Lowell Observatory Solar-Stellar Spectrograph, and the National Solar Observatory/Air Force Research Laboratory/Sacremento Peak K-line monitoring program. The Ca II H & K emission originates in the lower chromosphere and is strongly correlated with the presence of magnetic plage regions in the Sun. These synoptic observations allow us to trace the patterns long-term magnetic variability and explore dynamo behavior over a wide range of rotation regimes and stellar evolution timescales.

  4. Tanzania - Kigoma Solar Activity

    Data.gov (United States)

    Millennium Challenge Corporation — The performance evaluation of the Kigoma solar activity was designed to answer questions about the implementation of the program and about outcomes that may have...

  5. Solar sail mission design

    Energy Technology Data Exchange (ETDEWEB)

    Leipold, M.

    2000-02-01

    The main subject of this work is the design and detailed orbit transfer analysis of space flight missions with solar sails utilizing solar pressure for primary propulsion. Such a sailcraft requires ultra-light weight, gossamer-like deployable structures and materials in order to effectively utilize the transfer of momentum of solar photons. Different design concepts as well as technological elements for solar sails are considered, and an innovative design of a deployable sail structure including new methods for sail folding and unfolding is presented. The main focus of this report is on trajectory analysis, simulation and optimization of planetocentric as well as heliocentric low-thrust orbit transfers with solar sails. In a parametric analysis, geocentric escape spiral trajectories are simulated and corresponding flight times are determined. In interplanetary space, solar sail missions to all planets in our solar system as well as selected minor bodies are included in the analysis. Comparisons to mission concepts utilizing chemical propulsion as well as ion propulsion are included in order to assess whether solar sailing could possibly enhance or even enable this mission. The emphasis in the interplanetary mission analysis is on novel concepts: a unique method to realize a sun-synchronous Mercury orbiter, fast missions to the outer planets and the outer heliosphere applying a ''solar photonic assist'', rendezvous and sample return missions to asteroids and comets, as well as innovative concepts to reach unique vantage points for solar observation (''Solar Polar Orbiter'' and ''Solar Probe''). Finally, a propellant-less sailcraft attitude control concept using an external torque due to solar pressure is analyzed. Examples for sail navigation and control in circular Earth orbit applying a PD-control algorithm are shown, illustrating the maneuverability of a sailcraft. (orig.) [German] Gegenstand dieser

  6. Large Scale Solar Heating

    DEFF Research Database (Denmark)

    Heller, Alfred

    2001-01-01

    The main objective of the research was to evaluate large-scale solar heating connected to district heating (CSDHP), to build up a simulation tool and to demonstrate the application of the simulation tool for design studies and on a local energy planning case. The evaluation was mainly carried out...... model is designed and validated on the Marstal case. Applying the Danish Reference Year, a design tool is presented. The simulation tool is used for proposals for application of alternative designs, including high-performance solar collector types (trough solar collectors, vaccum pipe collectors......). Simulation programs are proposed as control supporting tool for daily operation and performance prediction of central solar heating plants. Finaly the CSHP technolgy is put into persepctive with respect to alternatives and a short discussion on the barries and breakthrough of the technology are given....

  7. The Solar Eclipse

    Science.gov (United States)

    Stern, David

    1970-01-01

    Instructions for observing the Solar Eclipse on Saturday, March 7, 1970, which will be total along a strip about 85 miles wide along the Atlantic Seaboard. Safety precautions and how to construct a pinhole camera to observe eclipse. (BR)

  8. Extraterrestrial Solar Neutrino Physics

    CERN Document Server

    Hwang, W-Y Pauchy

    2010-01-01

    We examine the scope of extraterrestrial solar neutrino physics, i.e. solar neutrino physics that could be carried out outside the Earth. We find that, among others, the reactions induced by the ^8B solar neutrinos, in view of the sole high energy nature (E_nu^max=14.03MeV), are most interesting in the solar environment. Two types of experiments are considered - the chemical compositions of the geology type and the matter-enhanced oscillations when the Sun-Venus-Earth eclipse, or the Sun-Mercury-Earth eclipse, occurs or the Satellite experiments (likely to be different from the "day-night" effect on the Earth). These experiments are not beyond current technology limits. In view of the weak-interaction nature, they are likely to be the precision experiments of the next generation or even beyond.

  9. THE THERMOELECTRIC SOLAR PANELS

    Directory of Open Access Journals (Sweden)

    R. Ahiska

    2016-07-01

    Full Text Available In this study, load characteristics of thermoelectric and photovoltaic solar panels are investigated and compared with each other with experiments. Thermoelectric solar panels converts the heat generated by sun directly to electricity; while, photovoltaic solar pales converts photonic energy from sun to electricity. In both types, maximum power can be obtained when the load resistance is equal to internal resistance. According to experimental results, power generated from unit surface with thermoelectric panel is 30 times greater than the power generated by photovoltaic panel. From a panel surface of 1 m2, thermoelectric solar panel has generated 4 kW electric power, while from the same surface, photovoltaic panel has generated 132 W only.

  10. The Solar Eclipse

    Science.gov (United States)

    Stern, David

    1970-01-01

    Instructions for observing the Solar Eclipse on Saturday, March 7, 1970, which will be total along a strip about 85 miles wide along the Atlantic Seaboard. Safety precautions and how to construct a pinhole camera to observe eclipse. (BR)

  11. Modeling of Solar Concentrators

    Science.gov (United States)

    Rockey, D. E.

    1984-01-01

    Algorithm developed for predicting power output, uniformity of intensity and operating temperature of concentrator-enhanced photovoltaic solar cell arrays. Optimum values for parameters such as reflector geometry found prior to constructing scale models for testing.

  12. Glass for Solar Concentrators

    Science.gov (United States)

    Bouquet, F. L.

    1984-01-01

    Report identifies four commercially available glasses as promising reflectors for solar concentrators. Have properties of high reflectance (80 to 96 percent), lower cost than first-surface silver metalization, and resistance to environmental forces.

  13. Boosting Solar Efficiency

    Directory of Open Access Journals (Sweden)

    Konika Gera

    2015-05-01

    Full Text Available Solar energy being most common form of renewable energy fails to hold its use in daily life because of its low efficiency and high maintenance costs. However, these short comings can be fought by using the electrostatic mechanism. In this, we charge the dust particles such that they are repelled by the solar panel itself and then removed. This mechanism is relatively cheaper and the power consumption of the same sums to almost zero. Also, efficiency can further be increased by using perovskites that forms an opaque layer over the solar panel. When both of these methods are used as a single hand, the efficiency increases drastically and can be easily employed in mega industries using mega solar panels.

  14. Welded solar cell interconnection

    Science.gov (United States)

    Stofel, E. J.; Browne, E. R.; Meese, R. A.; Vendura, G. J.

    1982-01-01

    The efficiency of the welding of solar-cell interconnects is compared with the efficiency of soldering such interconnects, and the cases in which welding may be superior are examined. Emphasis is placed on ultrasonic welding; attention is given to the solar-cell welding machine, the application of the welding process to different solar-cell configurations, producibility, and long-life performance of welded interconnects. Much of the present work has been directed toward providing increased confidence in the reliability of welding using conditions approximating those that would occur with large-scale array production. It is concluded that there is as yet insufficient data to determine which of three methods (soldering, parallel gap welding, and ultrasonic welding) provides the longest-duration solar panel life.

  15. Photovoltaic solar cell

    Energy Technology Data Exchange (ETDEWEB)

    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.

  16. Solar thermoelectric generator

    Science.gov (United States)

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

    2016-05-03

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

  17. 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.

  18. Space Solar Power Program

    Energy Technology Data Exchange (ETDEWEB)

    Arif, H.; Barbosa, H.; Bardet, C.; Baroud, M.; Behar, A.; Berrier, K.; Berthe, P.; Bertrand, R.; Bibyk, I.; Bisson, J.; Bloch, L.; Bobadilla, G.; Bourque, D.; Bush, L.; Carandang, R.; Chiku, T.; Crosby, N.; De Seixas, M.; De Vries, J.; Doll, S.; Dufour, F.; Eckart, P.; Fahey, M.; Fenot, F.; Foeckersperger, S.; Fontaine, J.E.; Fowler, R.; Frey, H.; Fujio, H.; Gasa, J.M.; Gleave, J.; Godoe, J.; Green, I.; Haeberli, R.; Hanada, T.; Ha

    1992-08-01

    Information pertaining to the Space Solar Power Program is presented on energy analysis; markets; overall development plan; organizational plan; environmental and safety issues; power systems; space transportation; space manufacturing, construction, operations; design examples; and finance.

  19. Solar cell radiation handbook

    Science.gov (United States)

    Tada, H. Y.; Carter, J. R., Jr.; Anspaugh, B. E.; Downing, R. G.

    1982-01-01

    The handbook to predict the degradation of solar cell electrical performance in any given space radiation environment is presented. Solar cell theory, cell manufacturing and how they are modeled mathematically are described. The interaction of energetic charged particles radiation with solar cells is discussed and the concept of 1 MeV equivalent electron fluence is introduced. The space radiation environment is described and methods of calculating equivalent fluences for the space environment are developed. A computer program was written to perform the equivalent fluence calculations and a FORTRAN listing of the program is included. Data detailing the degradation of solar cell electrical parameters as a function of 1 MeV electron fluence are presented.

  20. Solar system sputtering

    Science.gov (United States)

    Tombrello, T. A.

    1982-01-01

    The sites and materials involved in solar system sputtering of planetary surfaces are reviewed, together with existing models for the processes of sputtering. Attention is given to the interaction of the solar wind with planetary atmospheres in terms of the role played by the solar wind in affecting the He-4 budget in the Venus atmosphere, and the erosion and differentiation of the Mars atmosphere by solar wind sputtering. The study is extended to the production of isotopic fractionation and anomalies in interplanetary grains by irradiation, and to erosion effects on planetary satellites with frozen volatile surfaces, such as with Io, Europa, and Ganymede. Further measurements are recommended of the molecular form of the ejected material, the yields and energy spectra of the sputtered products, the iosotopic fractionation sputtering causes, and the possibility of electronic sputtering enhancement with materials such as silicates.

  1. Solar Imagery - GONG (Magnetogram)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Global Oscillation Network Group (GONG) is a network of 6 globally-spaced solar observatories that the NOAA Space Weather Prediction Center uses to monitor the...

  2. Solar Imagery - GONG

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Global Oscillation Network Group (GONG) is a network of 6 globally-spaced solar observatories that the NOAA Space Weather Prediction Center uses to monitor the...

  3. Solar Power Shines

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    While still in its infancy, the solar energy industry is growing in China as the country seeks clean, cheap and renewable sources of power Shi Zhengrong, President and CEO of Suntech Power Holdings Co. Ltd., was not a very familiar face to people outside the solar power industry until December 14 last year. On that day, Suntech, based in Wuxi, Jiangsu Province, became the first Chinese

  4. Alternative Solar Indices

    Energy Technology Data Exchange (ETDEWEB)

    Lantz, L.J.

    1980-07-01

    Possible alternative Solar Indices which could either be a perturbation from the currently defined Solar Index or possible indices based on current technologies for other media markets are discussed. An overview is given of the current project, including the logic that was utilized in defining its current structure and then alternative indices and definitions are presented and finally, recommendations are made for adopting alternative indices.

  5. Solar fuels generator

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, Nathan S.; Spurgeon, Joshua M.

    2016-10-25

    The solar fuels generator includes an ionically conductive separator between a gaseous first phase and a second phase. A photoanode uses one or more components of the first phase to generate cations during operation of the solar fuels generator. A cation conduit is positioned provides a pathway along which the cations travel from the photoanode to the separator. The separator conducts the cations. A second solid cation conduit conducts the cations from the separator to a photocathode.

  6. Tehnical day: solar energy

    OpenAIRE

    Carli, Barbara

    2012-01-01

    This dissertation presents an example of planning and carrying out a technical activity day in the field of solar energy in primary school grades 7 and 9. Firstly, we briefly present technical activity days, the goals and criteria for the planning of technical days, and the topics and devices connected to the technical day in question and were needed in the execution of the experiments. We have selected four simple experiments in the field of solar energy and prepared the needed worksheets fo...

  7. Solar system. Das Sonnensystem

    Energy Technology Data Exchange (ETDEWEB)

    Ryan, P.

    1981-01-01

    A comprehensive review is given of the most recent findings on the solar system. The physical processes in the sun are presented, their interactions in the interplanetary space, and the planets and moons of the solar system. The sun and the moon are discussed in great detail. The text is supplemented by excellent satellite pictures, including the latest pictures of Jupiter, Saturn, and their moons.

  8. Solar Physics at Evergreen

    Science.gov (United States)

    Zita, E. J.; Bogdan, T. J.; Carlsson, M.; Judge, P.; Heller, N.; Johnson, M.; Petty, S.

    2004-05-01

    We have recently established a solar physics research program at The Evergreen State College. Famed for its cloudy skies, the Pacific Northwest is an ideal location for solar physics research activities that do not require local observations. Collaborators from the High Altitude Observatory (HAO) at the National Center for Atmospheric Research have shared solar data from satellite-borne instruments such as TRACE and SUMER. HAO colleagues also share data from computer simulations of magneto-hydrodynamics (MHD) in the chromosphere, generated by the Institute for Theoretical Astrophysics (ITA) at the University of Oslo. Evergreen students and faculty learned to analyze data from satellites and simulations, in Boulder and Oslo, and established an infrastructure for continuing our analyses in Olympia. We are investigating the role of magnetic waves in heating the solar atmosphere. Comparing data from satellites and simulations shows that acoustic oscillations from the photosphere cannot effectively propagate into the chromosphere, but that magnetic waves can carry energy up toward the hot, thin corona. We find that acoustic waves can change into magnetic waves, especially near the magnetic "canopy," a region where the sound speed is comparable to magnetic wave speeds. Understanding MHD wave transformations and their role in energy transport can help answer outstanding questions about the anomalous heating of the solar atmosphere. Ref: Waves in the magnetized solar atmosphere II: Waves from localized sources in magnetic flux concentrations. Bogdan et al., 2003, ApJ 597

  9. Solar History An Introduction

    CERN Document Server

    Vita-Finzi, Claudio

    2013-01-01

    Beyond the four centuries of sunspot observation and the five decades during which artificial satellites have monitored the Sun – that is to say for 99.99999% of the Sun’s existence – our knowledge of solar history depends largely on analogy with kindred main sequence stars, on the outcome of various kinds of modelling, and on indirect measures of solar activity. They include the analysis of lunar rocks and meteorites for evidence of solar flares and other components of the solar cosmic-ray (SCR) flux, and the measurement of cosmogenic isotopes in wood, stratified ice and marine sediments to evaluate changes in the galactic cosmic-ray (GCR) flux and thus infer changes in the sheltering magnetic fields of the solar wind. In addition, shifts in the global atmospheric circulation which appear to result from cyclic fluctuations in solar irradiance have left their mark in river sediments and in the isotopic composition of cave deposits. In this volume the results these sources have already produced have bee...

  10. Solar Orbiter Status Report

    Science.gov (United States)

    Gilbert, Holly; St. Cyr, Orville Chris; Mueller, Daniel; Zouganelis, Yannis; Velli, Marco

    2017-08-01

    With the delivery of the instruments to the spacecraft builder, the Solar Orbiter mission is in the midst of Integration & Testing phase at Airbus in Stevenage, U.K. This mission to “Explore the Sun-Heliosphere Connection” is the first medium-class mission of ESA’s Cosmic Vision 2015-2025 program and is being jointly implemented with NASA. The dedicated payload of 10 remote-sensing and in-situ instruments will orbit the Sun as close as 0.3 A.U. and will provide measurments from the photosphere into the solar wind. The three-axis stabilized spacecraft will use Venus gravity assists to increase the orbital inclination out of the ecliptic to solar latitudes as high as 34 degrees in the extended mission. The science team of Solar Orbiter has been working closely with the Solar Probe Plus scientists to coordinate observations between these two highly-complementary missions. This will be a status report on the mission development; the interested reader is referred to the recent summary by Müller et al., Solar Physics 285 (2013).

  11. Cost effective solar Inverter

    Directory of Open Access Journals (Sweden)

    Nagarathna M

    2015-06-01

    Full Text Available Solar energy the most efficient, eco-friendly and abundantly available energy source in the nature. It can be converted into electrical energy in cost effective manner. In recent years, the interest in solar energy has risen due to surging oil prices and environmental concern. In many remote or underdeveloped areas, direct access to an electric grid is impossible and a photovoltaic inverter system would make life much simpler and more convenient. With this in mind, it is aimed to design, build, and test a solar panel inverter. This inverter system could be used as backup power during outages, battery charging, or for typical household applications. The main components of this solar system are solar cell, dc to dc boost converters, and inverter. Sine wave push pull inverter topology is used for inverter. In this topology only two MOSFETs are used and isolation requirement between control circuit and power circuit is also less which helps to decrease the cost of solar inverter.

  12. Anomalously Weak Solar Convection

    Science.gov (United States)

    Hanasoge, Shravan M.; Duvall, Thomas L.; Sreenivasan, Katepalli R.

    2012-01-01

    Convection in the solar interior is thought to comprise structures on a spectrum of scales. This conclusion emerges from phenomenological studies and numerical simulations, though neither covers the proper range of dynamical parameters of solar convection. Here, we analyze observations of the wavefield in the solar photosphere using techniques of time-distance helioseismology to image flows in the solar interior. We downsample and synthesize 900 billion wavefield observations to produce 3 billion cross-correlations, which we average and fit, measuring 5 million wave travel times. Using these travel times, we deduce the underlying flow systems and study their statistics to bound convective velocity magnitudes in the solar interior, as a function of depth and spherical- harmonic degree l..Within the wavenumber band l convective velocities are 20-100 times weaker than current theoretical estimates. This constraint suggests the prevalence of a different paradigm of turbulence from that predicted by existing models, prompting the question: what mechanism transports the heat flux of a solar luminosity outwards? Advection is dominated by Coriolis forces for wavenumbers l convection may be quasi-geostrophic. The fact that isorotation contours in the Sun are not coaligned with the axis of rotation suggests the presence of a latitudinal entropy gradient.

  13. Solar generation; Generation solaire

    Energy Technology Data Exchange (ETDEWEB)

    Villeneuve, J.

    2012-03-15

    Solar energy might become the main energy resource for mankind in the next 50 years. The author describes the assets of photovoltaic energy and helio-thermodynamics and reviews the conditions required for such a future. The first condition is an integrated approach for the development of solar energy in buildings, it means to develop in parallel the use of low-power appliances, to insulate buildings, to use daylight. Secondly to find an efficient solution to store solar energy. In the building sector this solution could be the use of solar energy (through solar panels) and geothermal heat pump to be able to recover in winter the calories caught in summer and stored in the ground. In a warmer and warmer world, the production of cold from solar calories has the advantage of sparing electricity and to make the demand for calories corresponding with the peak of the resource. A graph shows that the expected cost of photovoltaic electricity in 2020 will be half the 2011 cost and will correspond to the retail price of electricity. (A.C.)

  14. The Stardust solar array

    Science.gov (United States)

    Gasner, S.; Sharmit, K.; Stella, P. M.; Craig, C.; Mumaw, S.

    2003-01-01

    The Stardust program, part of NASA's Discovery Missions was launched on February 7. 1999. It's seven-year mission is to gather interstellar dust and material from the comet Wild-2 and return the material to earth in January 2006. In order to accomplish this mission, the satellite will orbit the sun a total of three times, traversing distances from a little under 1 AU to 2.7 AU. On April 18 2002 , the Stardust spacecraft reached its furthest distance and broke the record for being the farthest spacecraft from the sun powered by solar energy, The Stardust solar panels were built with standard off the shelf 10 Ohm-cm high efficiency silicon solar cells. These solar cells are relatively inexpensive and have shown excellent characteristics under LILT conditions. In order to accommodate the varying temperature and intensity conditions on the electrical power subsystem, an electronic switch box was designed to reconfigure the string length and number of swings depending on the mission phase. This box allowed the use of an inexpensive direct energy transfer system for the electrical power system architecture. The solar panels and electrical power system have met all requirements. Telemetry data from the solar panels at 2.7 AU are in excellent agreement with flight predictions.

  15. Solar Thermal Storage System

    Directory of Open Access Journals (Sweden)

    Arjun A. Abhyankar

    2012-06-01

    Full Text Available Increasing energy consumption, shrinking resources and rising energy costs will have significant impact on our standard of living for future generations. In this situation, the development of alternative, cost effective sources of energy has to be a priority. This project presents the advanced technology and some of the unique features of a novel solar system that utilizes solar energy for space heating and water heating purpose in residential housing and commercial buildings. The improvements in solar technology offers a significant cost reduction, to a level where the solar system can compete with the energy costs from existing sources. The main goal of the project is to investigate new or advanced solutions for storing heat in systems providing heating. which can be achieved using phase change material(PCM.A phase change material with a melting/solidification temperature of 50ºC to 60ºC is used for solar heat storage. When the PCM undergoes the phase change, it can absorb or release a large amount of energy as latent heat. This heat can be used for further applications like water heating and space heating purposes. Thus solar thermal energy is widely use

  16. Photovoltaic solar energy; Energia solar fotovoltaica

    Energy Technology Data Exchange (ETDEWEB)

    Fraidenraich, Naum; Tiba, Chigueru; Vilela, Olga de Castro; Barbosa, Elielza Moura de Souza [Universidade Federal de Pernambuco(UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear (DEN). Grupo de Pesquisas em Fontes Alternativas de Energia

    2003-07-01

    This chapter gives an overview on energy generation from thermal solar energy, analysing the international markets of the photovoltaic modules, the changes which are being produced in the application character, the environmental phenomena resulting from the modules production, briefly describes the physical phenomena explaining the photovoltaic effect, analyses the process of module price formation and performs the energy costs resultant for the user and subsides politics being practiced in various countries.

  17. Simulations of Solar Jets

    Science.gov (United States)

    Kohler, Susanna

    2017-02-01

    Formation of a coronal jet from twisted field lines that have reconnected with the ambient field. The colors show the radial velocity of the plasma. [Adapted from Szente et al. 2017]How do jets emitted from the Suns surface contribute to its corona and to the solar wind? In a recent study, a team of scientists performed complex three-dimensional simulations of coronal jets to answer these questions.Small ExplosionsCoronal jets are relatively small eruptions from the Suns surface, with heights of roughly 100 to 10,000 km, speeds of 10 to 1,000 km/s, and lifetimes of a few minutes to around ten hours. These jets are constantly present theyre emitted even from the quiet Sun, when activity is otherwise low and weve observed them with a fleet of Sun-watching space telescopes spanning the visible, extreme ultraviolet (EUV), and X-ray wavelength bands.A comparison of simulated observations based on the authors model (left panels) to actual EUV and X-ray observations of jets (right panels). [Szente et al. 2017]Due to their ubiquity, we speculate that these jets might contribute to heating the global solar corona (which is significantly hotter than the surface below it, a curiosity known as the coronal heating problem). We can also wonder what role these jets might play in driving the overall solar wind.Launching a JetLed by Judit Szente (University of Michigan), a team of scientists has explored the impact of coronal jets on the global corona and solar wind with a series of numerical simulations. Szente and collaborators used three-dimensional, magnetohydrodynamic simulations that provide realistic treatment of the solar atmosphere, the solar wind acceleration, and the complexities of heat transfer throughout the corona.In the authors simulations, a jet is initiated as a magnetic dipole rotates at the solar surface, winding up field lines. Magnetic reconnection between the twisted lines and the background field then launches the jet from the dense and hot solar

  18. Solar thermophotovoltaics: reshaping the solar spectrum

    Science.gov (United States)

    Zhou, Zhiguang; Sakr, Enas; Sun, Yubo; Bermel, Peter

    2016-06-01

    Recently, there has been increasing interest in utilizing solar thermophotovoltaics (STPV) to convert sunlight into electricity, given their potential to exceed the Shockley-Queisser limit. Encouragingly, there have also been several recent demonstrations of improved system-level efficiency as high as 6.2%. In this work, we review prior work in the field, with particular emphasis on the role of several key principles in their experimental operation, performance, and reliability. In particular, for the problem of designing selective solar absorbers, we consider the trade-off between solar absorption and thermal losses, particularly radiative and convective mechanisms. For the selective thermal emitters, we consider the tradeoff between emission at critical wavelengths and parasitic losses. Then for the thermophotovoltaic (TPV) diodes, we consider the trade-off between increasing the potential short-circuit current, and maintaining a reasonable opencircuit voltage. This treatment parallels the historic development of the field, but also connects early insights with recent developments in adjacent fields.With these various components connecting in multiple ways, a system-level end-to-end modeling approach is necessary for a comprehensive understanding and appropriate improvement of STPV systems. This approach will ultimately allow researchers to design STPV systems capable of exceeding recently demonstrated efficiency values.

  19. Solar electron source and thermionic solar cell

    Directory of Open Access Journals (Sweden)

    Parham Yaghoobi

    2012-12-01

    Full Text Available Common solar technologies are either photovoltaic/thermophotovoltaic, or use indirect methods of electricity generation such as boiling water for a steam turbine. Thermionic energy conversion based on the emission of electrons from a hot cathode into vacuum and their collection by an anode is also a promising route. However, thermionic solar conversion is extremely challenging as the sunlight intensity is too low for heating a conventional cathode to thermionic emission temperatures in a practical manner. Therefore, compared to other technologies, little has been done in this area, and the devices have been mainly limited to large experimental apparatus investigated for space power applications. Based on a recently observed “Heat Trap” effect in carbon nanotube arrays, allowing their efficient heating with low-power light, we report the first compact thermionic solar cell. Even using a simple off-the-shelf focusing lens, the device delivered over 1 V across a load. The device also shows intrinsic storage capacity.

  20. Astroparticle physics with solar neutrinos

    Science.gov (United States)

    NAKAHATA, Masayuki

    2011-01-01

    Solar neutrino experiments observed fluxes smaller than the expectations from the standard solar model. This discrepancy is known as the “solar neutrino problem”. Flux measurements by Super-Kamiokande and SNO have demonstrated that the solar neutrino problem is due to neutrino oscillations. Combining the results of all solar neutrino experiments, parameters for solar neutrino oscillations are obtained. Correcting for the effect of neutrino oscillations, the observed neutrino fluxes are consistent with the prediction from the standard solar model. In this article, results of solar neutrino experiments are reviewed with detailed descriptions of what Kamiokande and Super-Kamiokande have contributed to the history of astroparticle physics with solar neutrino measurements. PMID:21558758

  1. Astroparticle physics with solar neutrinos.

    Science.gov (United States)

    Nakahata, Masayuki

    2011-01-01

    Solar neutrino experiments observed fluxes smaller than the expectations from the standard solar model. This discrepancy is known as the "solar neutrino problem". Flux measurements by Super-Kamiokande and SNO have demonstrated that the solar neutrino problem is due to neutrino oscillations. Combining the results of all solar neutrino experiments, parameters for solar neutrino oscillations are obtained. Correcting for the effect of neutrino oscillations, the observed neutrino fluxes are consistent with the prediction from the standard solar model. In this article, results of solar neutrino experiments are reviewed with detailed descriptions of what Kamiokande and Super-Kamiokande have contributed to the history of astroparticle physics with solar neutrino measurements. (Communicated by Toshimitsu Yamazaki, M.J.A.).

  2. Discovering the Solar System

    Science.gov (United States)

    Jones, Barrie W.

    1999-04-01

    Discovering the Solar System Barrie W. Jones The Open University, Milton Keynes, UK Discovering the Solar System is a comprehensive, up-to-date account of the Solar System and of the ways in which the various bodies have been investigated and modelled. The approach is thematic, with sequences of chapters on the interiors of planetary bodies, on their surfaces, and on their atmospheres. Within each sequence there is a chapter on general principles and processes followed by one or two chapters on specific bodies. There is also an introductory chapter, a chapter on the origin of the Solar System, and a chapter on asteroids, comets and meteorites. Liberally illustrated with diagrams, black and white photographs and colour plates, Discovering the Solar System also features: * tables of essential data * question and answers within the text * end of section review questions with answers and comments Discovering the Solar System is essential reading for all undergraduate students for whom astronomy or planetary science are components of their degrees, and for those at a more advanced level approaching the subject for the first time. It will also be of great interest to non-specialists with a keen interest in astronomy. A small amount of scientific knowledge is assumed plus familiarity with basic algebra and graphs. There is no calculus. Praise for this book includes: ".certainly qualifies as an authoritative text. The author clearly has an encyclopedic knowledge of the subject." Meteorics and Planetary Science ".liberally doused with relevant graphs, tables, and black and white figures of good quality." EOS, Transactions of the American Geophysical Union ".one of the best books on the Solar System I have seen. The general accuracy and quality of the content is excellent." Journal of the British Astronomical Association

  3. Technical use of solar energy: Conversion from solar to thermal energy, solar cooling and thermal energy storage

    Science.gov (United States)

    Arafa, A.; Fisch, N.; Hahne, E.; Kraus, K.; Seemann, D.; Seifert, B.; Sohns, J.; Schetter, G.; Schweigerer, W.

    1983-12-01

    Experimental and theoretical studies in the field of solar energy utilization are reviewed. Specific topics considered are: flat plate water collectors, solar absorbers, air collectors, solar absorption cooling, solar simulators, aquifiers, latent heat stores, and space heating systems.

  4. Solar neutrinos, solar flares, solar activity cycle and the proton decay

    Science.gov (United States)

    Raychaudhuri, P.

    1985-01-01

    It is shown that there may be a correlation between the galactic cosmic rays and the solar neutrino data, but it appears that the neutrino flux which may be generated during the large solar cosmic ray events cannot in any way effect the solar neutrino data in Davis experiment. Only initial stage of mixing between the solar core and solar outer layers after the sunspot maximum in the solar activity cycle can explain the higher (run number 27 and 71) of solar neutrino data in Davis experiment. But solar flare induced atmospheric neutrino flux may have effect in the nucleon decay detector on the underground. The neutrino flux from solar cosmic rays may be a useful guide to understand the background of nucleon decay, magnetic monopole search, and the detection of neutrino flux in sea water experiment.

  5. Solar thermal financing guidebook

    Energy Technology Data Exchange (ETDEWEB)

    Williams, T.A.; Cole, R.J.; Brown, D.R.; Dirks, J.A.; Edelhertz, H.; Holmlund, I.; Malhotra, S.; Smith, S.A.; Sommers, P.; Willke, T.L.

    1983-05-01

    This guidebook contains information on alternative financing methods that could be used to develop solar thermal systems. The financing arrangements discussed include several lease alternatives, joint venture financing, R and D partnerships, industrial revenue bonds, and ordinary sales. In many situations, alternative financing arrangements can significantly enhance the economic attractiveness of solar thermal investments by providing a means to efficiently allocate elements of risk, return on investment, required capital investment, and tax benefits. A net present value approach is an appropriate method that can be used to investigate the economic attractiveness of alternative financing methods. Although other methods are applicable, the net present value approach has advantages of accounting for the time value of money, yielding a single valued solution to the financial analysis, focusing attention on the opportunity cost of capital, and being a commonly understood concept that is relatively simple to apply. A personal computer model for quickly assessing the present value of investments in solar thermal plants with alternative financing methods is presented in this guidebook. General types of financing arrangements that may be desirable for an individual can be chosen based on an assessment of his goals in investing in solar thermal systems and knowledge of the individual's tax situation. Once general financing arrangements have been selected, a screening analysis can quickly determine if the solar investment is worthy of detailed study.

  6. Searchable solar feature catalogues

    Science.gov (United States)

    Zharkova, V. V.; Aboudarham, J.; Zharkov, S.; Ipson, S. S.; Benkhalil, A. K.; Fuller, N.

    The searchable Solar Feature Catalogues (SFCs) are developed from digitized solar images using automated pattern recognition techniques. The techniques were applied for the detection of sunspots, active regions, filaments and line-of-sight magnetic neutral lines in automatically standardized full disk solar images in Ca II K1, Ca II K3 and Ha lines taken at the Paris-Meudon Observatory and white light images and magnetograms from SOHO/MDI. The results of the automated recognition were verified with manual synoptic maps and available statistical data that revealed good detection accuracy. Based on the recognized parameters, a structured database of Solar Feature Catalogues was built on a MySQL server for every feature and published with various pre-designed search pages on the Bradford University web site http://www.cyber.brad.ac.uk/egso/SFC/. The SFCs with nine year coverage (1996-2004) is to be used for deeper investigation of the feature classification and solar activity forecast.

  7. Radiochemical solar neutrino experiments

    CERN Document Server

    Gavrin, V N

    2011-01-01

    Radiochemical experiments have been crucial to solar neutrino research. Even today, they provide the only direct measurement of the rate of the proton-proton fusion reaction, p + p --> d + e^+ + nu_e, which generates most of the Sun's energy. We first give a little history of radiochemical solar neutrino experiments with emphasis on the gallium experiment SAGE -- the only currently operating detector of this type. The combined result of all data from the Ga experiments is a capture rate of 67.6 +/- 3.7 SNU. For comparison to theory, we use the calculated flux at the Sun from a standard solar model, take into account neutrino propagation from the Sun to the Earth and the results of neutrino source experiments with Ga, and obtain 67.3 ^{+3.9}_{-3.5} SNU. Using the data from all solar neutrino experiments we calculate an electron neutrino pp flux at the earth of (3.41 ^{+0.76}_{-0.77}) x 10^{10}/(cm^2-s), which agrees well with the prediction from a detailed solar model of (3.30 ^{+0.13} _{-0.14}) x 10^{10}/(cm^...

  8. Nanocrystal Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Gur, Ilan [Univ. of California, Berkeley, CA (United States)

    2006-01-01

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

  9. The outer solar system

    Directory of Open Access Journals (Sweden)

    Encrenaz T.

    2009-02-01

    Full Text Available The outer solar system extends beyond a heliocentric distance of 5 AU. It contains the giant planets and their systems (rings and satellites, the Kuiper belt, the comets (except those which approach episodically the inner solar system and, at its outer edge, the Oort cloud. The outer solar system physically corresponds to the region located outside the « snow line » which corresponded to the distance of ice condensation in the protodolar disk, and thus made the frontier between the terrestrial and the giant planets at the time of the planets’ formation. The outer solar system is charaterized by a very large variety of ob jects, even within a given class of ob jects. Each of the giant planet has its own properties, as well as each of the outer satellites and the ring systems ; all are the products of specific conditions which determined their formation and evolution processes. The existence of the Kuiper belt, suspected on theoretical bases since the 1940s, has been confirmed since 1992 with the observation of over 1200 trans-neptunian ob jects. Thanks to the the developments of more and more performing groundbased instrumentation and the use of large telescopes, these ob jects are now studies in a statistical way, both dynamically and physically, and these studies are precious for constraining the early formation models of the solar system.

  10. Solar tomography adaptive optics.

    Science.gov (United States)

    Ren, Deqing; Zhu, Yongtian; Zhang, Xi; Dou, Jiangpei; Zhao, Gang

    2014-03-10

    Conventional solar adaptive optics uses one deformable mirror (DM) and one guide star for wave-front sensing, which seriously limits high-resolution imaging over a large field of view (FOV). Recent progress toward multiconjugate adaptive optics indicates that atmosphere turbulence induced wave-front distortion at different altitudes can be reconstructed by using multiple guide stars. To maximize the performance over a large FOV, we propose a solar tomography adaptive optics (TAO) system that uses tomographic wave-front information and uses one DM. We show that by fully taking advantage of the knowledge of three-dimensional wave-front distribution, a classical solar adaptive optics with one DM can provide an extra performance gain for high-resolution imaging over a large FOV in the near infrared. The TAO will allow existing one-deformable-mirror solar adaptive optics to deliver better performance over a large FOV for high-resolution magnetic field investigation, where solar activities occur in a two-dimensional field up to 60'', and where the near infrared is superior to the visible in terms of magnetic field sensitivity.

  11. Solar System Educators Program

    Science.gov (United States)

    Knudsen, R.

    2004-11-01

    The Solar System Educators Program is a nationwide network of highly motivated teachers who lead workshops that show other teachers in their local communities how to successfully incorporate NASA materials and research into their classes. Currently there are 57 Solar System Educators in 37 states whose workshops are designed to assist their fellow teachers in understanding and including standards-based NASA materials into their classroom activities. Solar System Educators attend a training institute during their first year in the program and have the option of attending subsequent annual institutes. The volunteers in this program receive additional web-based mission-specific telecon trainings in conjunction with the Solar System Ambassadors. Resource and handout materials in the form of DVDs, posters, pamphlets, fact sheets, postcards and bookmarks are also provided. Scientists can get involved with this program by partnering with the Solar System Educators in their regions, presenting at their workshops and mentoring these outstanding volunteers. This formal education program helps optimize project funding set aside for education through the efforts of these volunteer master teachers. At the same time, teachers become familiar with NASA's educational materials with which to inspire students into pursuing careers in science, technology, engineering and math.

  12. Solar coronal jets

    Science.gov (United States)

    Dobrzyck, D.

    The solar jets were first observed by SOHO instruments (EIT, LASCO, UVCS) during the previous solar minimum. They were small, fast ejections originating from flaring UV bright points within large polar coronal holes. The obtained data provided us with estimates of the jet plasma conditions, dynamics, evolution of the electron temperature and heating rate required to reproduce the observed ionization state. To follow the polar jets through the solar cycle a special SOHO Joint Observing Program (JOP 155) was designed. It involves a number of SOHO instruments (EIT, CDS, UVCS, LASCO) as well as TRACE. The coordinated observations have been carried out since April 2002. The data enabled to identify counterparts of the 1996-1998 solar minimum jets. Their frequency of several events per day appear comparable to the frequency from the previous solar minimum. The jets are believed to be triggered by field line reconnection between emerging magnetic dipole and pre-existing unipolar field. Existing models predict that the hot jet is formed together with another jet of a cool material. The particular goal of the coordinated SOHO and TRACE observations was to look for possible association of the hot and cool plasma ejections. Currently there is observational evidence that supports these models.

  13. Combined solar collector

    OpenAIRE

    Voznyak, O.; Shapoval, S.; Pona, O.; Vengryn, I.

    2014-01-01

    In this article was analyzing the efficiency of the combined solar collector for heating buildings. This enhances the efficiency of solar system by increasing the area of the absorption of solar energy. There are describes the results of the research on solar radiation input on a combined solar collector. Проаналізовано ефективність використання комбінованого сонячного колектора для теплопостачання будівель. Він забезпечує підвищення ефективності геліосистеми за рахунок збільшення площі погли...

  14. Solar Divergence Collimators for Optical Characterisation of Solar Components

    Directory of Open Access Journals (Sweden)

    D. Fontani

    2013-01-01

    Full Text Available Experimentation and laboratory optical tests on solar components are central aspects of the research on renewable energies. The key element of the proposed testing systems is a solar divergence collimator, which exactly reproduces in laboratory the sunlight divergence, while commercial solar simulators are mainly aimed to replicate intensity and spectrum of the sun. Precise solar divergence reproduction is essential to correctly assess the optical properties and to simulate the operative conditions of a solar collecting device. Optical characterisation and experimentation can give information about production quality and homogeneity; moreover, specific tests can address the serial production of solar components detecting defects type and location. For Concentrating Photovoltaic systems, appropriate tests can analyze solar concentrators of various shapes, dimensions, and collection features. Typically, to characterise a solar component the most important and commonly examined quantities are collection efficiency, image plane analysis, and angle dependence.

  15. Solar-powered airship. Solar angetriebenes Luftschiff

    Energy Technology Data Exchange (ETDEWEB)

    Knaupp, W. (Zentrum fuer Sonnenenergie- und Wasserstoff-Forschung Baden-Wuerttemberg, Stuttgart (Germany)); Rehmet, M.A. (Inst. fuer Statik und Dynamik der Luft- und Raumfahrtkonstruktionen, Univ. Stuttgart (Germany))

    1994-01-01

    Two solar-powered airships were designed and built within 20 months. The principal aim was to identify ecological alternatives within individual technological fields of air traffic and to demonstrate their feasibility. The project is directed at the design of an ultra-light-weight remote-controlled airship (length 16m) with a video camera for on-line transmission of images and flight data. A particular technological challenge is posed by the design of a light-weight flexible photovoltaic generator and its integration with the airship shell. (orig./BWI)

  16. Solar activity and earthquake

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, J.

    1979-02-26

    Prolonged astronomical observations have discovered that the Sun, which is the nearest star to the Earth, is not calm and serene. On the solar surface, there are often windstorms, electrical lights, and sometimes large flame eruptions; and there are regularly black spots in patches which are also active. The Sun not only disperses light and heat, but also throws out large quantities of currents of charged particles to be scattered in space and to reach the Earth, sometimes, which are called by some solar winds. These activities in the Sun can induce many physical phenomena on earth, including magnetic storms, polar light, sudden disruption or attenuation of medium- and short-wave radio, and many atmospheric changes. Some scientists believe they are perhaps also related to the occurrence of earthquakes. This paper explains these solar activities and their possible relationship to earthquakes.

  17. Photovoltaic solar energy conversion

    CERN Document Server

    Bauer, Gottfried H

    2015-01-01

    This concise primer on photovoltaic solar energy conversion invites readers to reflect on the conversion of solar light into energy at the most fundamental level and encourages newcomers to the field to help find meaningful answers on how photovoltaic solar energy conversion can work (better), eventually contributing to its ongoing advancement. The book is based on lectures given to graduate students in the Physics Department at the University of Oldenburg over the last two decades, yet also provides an easy-to-follow introduction for doctoral and postdoctoral students from related disciplines such as the materials sciences and electrical engineering. Inspired by classic textbooks in the field, it reflects the author’s own ideas on how to understand, visualize and eventually teach the microscopic physical mechanisms and effects, while keeping the text as concise as possible so as to introduce interested readers to the field and balancing essential knowledge with open questions.

  18. Winnebago Tribe Solar Project

    Energy Technology Data Exchange (ETDEWEB)

    Nieman, Autumn [Winnebago Tribe of Nebraska Solar Project (United States)

    2016-02-26

    The strategy of the Solar Project was to reduce fuel use within two years by a roof mounted photovoltaic system. The police/fire building is completely powered by electricity. The renewable energy system we have selected has a power capacity of 23kW and the ability to export 44.3 MWh. We anticipate 32.55% kWh energy savings, an excess of the required 30% reduction, in the building’s total fuel use based on the most current 12 months of data (2012). The solar electric system is a grid-tie, ballast mounted on a flat roof over the police/fire station. The solar electric system includes 280 Watt modules for a nominal total of 22.80 kW. Approximately 84 modules are ballast mounted to the flat roof facing south.

  19. Solar neutrino detection

    CERN Document Server

    Miramonti, Lino

    2009-01-01

    More than 40 years ago, neutrinos where conceived as a way to test the validity of the solar models which tell us that stars are powered by nuclear fusion reactions. The first measurement of the neutrino flux, in 1968 in the Homestake mine in South Dakota, detected only one third of the expected value, originating what has been known as the Solar Neutrino Problem. Different experiments were built in order to understand the origin of this discrepancy. Now we know that neutrinos undergo oscillation phenomenon changing their nature traveling from the core of the Sun to our detectors. In the work the 40 year long saga of the neutrino detection is presented; from the first proposals to test the solar models to last real time measurements of the low energy part of the neutrino spectrum.

  20. The Global Solar Dynamo

    Science.gov (United States)

    Cameron, R. H.; Dikpati, M.; Brandenburg, A.

    2017-09-01

    A brief summary of the various observations and constraints that underlie solar dynamo research are presented. The arguments that indicate that the solar dynamo is an alpha-omega dynamo of the Babcock-Leighton type are then shortly reviewed. The main open questions that remain are concerned with the subsurface dynamics, including why sunspots emerge at preferred latitudes as seen in the familiar butterfly wings, why the cycle is about 11 years long, and why the sunspot groups emerge tilted with respect to the equator (Joy's law). Next, we turn to magnetic helicity, whose conservation property has been identified with the decline of large-scale magnetic fields found in direct numerical simulations at large magnetic Reynolds numbers. However, magnetic helicity fluxes through the solar surface can alleviate this problem and connect theory with observations, as will be discussed.

  1. Metasurface Broadband Solar Absorber

    CERN Document Server

    Azad, A K; Sykora, M; Weisse-Bernstein, N R; Luk, T S; Taylor, A J; Dalvit, D A R; Chen, H -T

    2015-01-01

    We demonstrate a broadband, polarization independent, omnidirectional absorber based on a metallic metasurface architecture, which accomplishes greater than 90% absorptance in the visible and near-infrared range of the solar spectrum, and exhibits low emissivity at mid- and far-infrared wavelengths. The complex unit cell of the metasurface solar absorber consists of eight pairs of gold nano-resonators that are separated from a gold ground plane by a thin silicon dioxide spacer. Our experimental measurements reveal high-performance absorption over a wide range of incidence angles for both s- and p-polarizations. We also investigate numerically the frequency-dependent field and current distributions to elucidate how the absorption occurs within the metasurface structure. Furthermore, we discuss the potential use of our metasurface absorber design in solar thermophotovoltaics by exploiting refractory plasmonic materials.

  2. Solar heating wall

    Energy Technology Data Exchange (ETDEWEB)

    Schoenfelder, J.L.

    1983-08-16

    A solar heating wall is disclosed including a water pipe circulation system having a plurality of separate tubes, each formed as a loop, connected between a water supply and a return. The separate tubes are arranged in a single vertical plane at the approximate center of the wall. The wall is formed within a frame which is packed with a material suited for use as a thERMAL RESERVOIR, SUCH AS concrete. The frame provides extra support by having a series of horizontally disposed cross supports on one surface of the wall and a series of vertically disposed cross supports on the opposite surface A pressure relief valve may be provided between the water supply to the separate tubes and the water supply to the building or structure containing the solar wall, so that the solar wall can be adapted for use with a city water system.

  3. Cookers for solar homes

    Energy Technology Data Exchange (ETDEWEB)

    Khalifa, A.M.A.; Akyurt, M.; Taha, M.M.A.

    1986-01-01

    Means of piping solar energy into kitchens were investigated. Two different solar cookers utilising the heat-pipe principle were designed, constructed and tested. A cooker utilising an east-west line focusing collector, designated Mecca-1, was developed for this purpose. The second cooker was a flat-plate heat-pipe cooker, Mecca-2. A single heat pipe in each cooker absorbed the energy at the collector, transported it into the kitchen and delivered it to an insulated oven at the condenser end. Various heating and boiling experiments conducted on the two cookers demonstrated the feasibility of the concept. It was found that the Mecca-2 cooker with triple glazing had a utilisation efficiency of up to 19 per cent and could boil 1 litre of water in 27 min for a solar insolation of 900 W/m/sup 2/.

  4. The Global Solar Dynamo

    CERN Document Server

    Cameron, R H; Brandenburg, A

    2016-01-01

    A brief summary of the various observations and constraints that underlie solar dynamo research are presented. The arguments that indicate that the solar dynamo is an alpha-omega dynamo of the Babcock-Leighton type are then shortly reviewed. The main open questions that remain are concerned with the subsurface dynamics, including why sunspots emerge at preferred latitudes as seen in the familiar butterfly wings, why the cycle is about 11 years long, and why the sunspot groups emerge tilted with respect to the equator (Joy's law). Next, we turn to magnetic helicity, whose conservation property has been identified with the decline of large-scale magnetic fields found in direct numerical simulations at large magnetic Reynolds numbers. However, magnetic helicity fluxes through the solar surface can alleviate this problem and connect theory with observations, as will be discussed.

  5. Why Not Solar Power?

    Science.gov (United States)

    Pokharel, Reeju; Sheldon, Peter

    2008-03-01

    Most of the world generally depends on energy sources such as fossil fuels and nuclear power to meet our energy consumption needs. As we all know, the excessive use of these resources has large environmental impacts, including displacing habitats, pollution, global warming, and scarcity of resources. Solar power is a clean form of energy that has the potential to fulfill our energy needs while balancing the natural state of our environment. So why do we not power our houses with solar energy? I will give a general overview of the working principles of commercially available solar power, and examine the issues relating to why we should use it and why we currently do not.

  6. 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.

  7. Solar Indices Forecasting Tool

    Science.gov (United States)

    Henney, Carl John; Shurkin, Kathleen; Arge, Charles; Hill, Frank

    2016-05-01

    Progress to forecast key space weather parameters using SIFT (Solar Indices Forecasting Tool) with the ADAPT (Air Force Data Assimilative Photospheric flux Transport) model is highlighted in this presentation. Using a magnetic flux transport model, ADAPT, we estimate the solar near-side field distribution that is used as input into empirical models for predicting F10.7(solar 10.7 cm, 2.8 GHz, radio flux), the Mg II core-to-wing ratio, and selected bands of solar far ultraviolet (FUV) and extreme ultraviolet (EUV) irradiance. Input to the ADAPT model includes the inferred photospheric magnetic field from the NISP ground-based instruments, GONG & VSM. Besides a status update regarding ADAPT and SIFT models, we will summarize the findings that: 1) the sum of the absolute value of strong magnetic fields, associated with sunspots, is shown to correlate well with the observed daily F10.7 variability (Henney et al. 2012); and 2) the sum of the absolute value of weak magnetic fields, associated with plage regions, is shown to correlate well with EUV and FUV irradiance variability (Henney et al. 2015). This work utilizes data produced collaboratively between Air Force Research Laboratory (AFRL) and the National Solar Observatory (NSO). The ADAPT model development is supported by AFRL. The input data utilized by ADAPT is obtained by NISP (NSO Integrated Synoptic Program). NSO is operated by the Association of Universities for Research in Astronomy (AURA), Inc., under a cooperative agreement with the National Science Foundation (NSF). The 10.7 cm solar radio flux data service, utilized by the ADAPT/SIFT F10.7 forecasting model, is operated by the National Research Council of Canada and National Resources Canada, with the support of the Canadian Space Agency.

  8. Advanced solar panel designs

    Science.gov (United States)

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

    1996-01-01

    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 cm(exp 2) 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 cm(exp 2) coupon was fabricated and tested to demonstrate 105 W/kg with the potential of achieving 115 W/kg. This paper will address the construction details for the GaAs/isogrid and dual-junction GaAs/carbon mesh panel configurations. These are ultimately sized to provide 75 Watts and 119 Watts respectively for smallsats or may be used as modular building blocks for larger systems. GaAs/isogrid and dual-junction GaAs/carbon mesh coupons have been fabricated and tested to successfully demonstrate critical performance parameters and results are also provided here.

  9. Future Directions in Solar Physics

    Science.gov (United States)

    Rabin, Douglas

    2010-01-01

    I will discuss scientific opportunities for space-based solar physics instruments in the coming decade and their synergy with major new ground-based telescopes. l will also discuss ( pow small satellites may complement larger solar physics missions.

  10. Mars Solar Balloon Lander Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Mars Solar Balloon Lander (MSBL) is a novel concept which utilizes the capability of solar-heated hot air balloons to perform soft landings of scientific...

  11. Studies efficiency solar air collector

    OpenAIRE

    YORKIN SODIKOVICH ABBASOV; MIRSOLI ODILJANOVICH UZBEKOV

    2016-01-01

    The article presents an analysis of the existing solar air collectors. A description of the design and the results of experimental studies on the effectiveness of the solar air collector with an absorber of from metal shavings.

  12. 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.

  13. Manhattan Solar Cannon

    Science.gov (United States)

    Treffers, Richard R.; Loisos, George; Ubbelohde, Susan; Douglas, Susanna; Pintos, Eduardo; Mulherin, James; Pasley, David

    2015-01-01

    We describe a 2.4 m hexagonal solar collector atop a Manhattan office building used for a solar / arts project. The collector uses an afocal design to concentrate the sunlight into a 0.6 m diameter beam which is directed by mirrors into a 80 m long fiber optic sculpture which descends an interior stairwell. The collector is fully steerable and follows the sun each day robotically. The control system and the optical design of the collector as well as the fiber optic sculpture will be discussed.

  14. Characterization of solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Haerkoenen, J.; Tuominen, E.; Nybergh, K.; Ezer, Y.; Yli-Koski, M.; Sinkkonen, J. [Helsinki Univ. of Technology, Otaniemi (Finland). Dept. of Electrical and Communications Engineering

    1998-10-01

    Photovoltaic research in the Electron Physics Laboratory started in 1993, when laboratory joined the national TEKES/NEMO 2 research program. Since the beginning of the project, characterization as well as experimentally orientated development of the fabrication process of the solar cells were carried out parallery. The process development research started by the initiatives of the Finnish industry. At the moment a large amount of the laboratory personnel works on solar cell research and the financing comes mainly from external projects. The funding for the research has come from TEKES, Ministry of Education, Finnish Academy, GETA graduate school, special equipment grants of the university, and from the laboratory

  15. Solar industrial process heat

    Energy Technology Data Exchange (ETDEWEB)

    Lumsdaine, E.

    1981-04-01

    The aim of the assessment reported is to candidly examine the contribution that solar industrial process heat (SIPH) is realistically able to make in the near and long-term energy futures of the United States. The performance history of government and privately funded SIPH demonstration programs, 15 of which are briefly summarized, and the present status of SIPH technology are discussed. The technical and performance characteristics of solar industrial process heat plants and equipment are reviewed, as well as evaluating how the operating experience of over a dozen SIPH demonstration projects is influencing institutional acceptance and economoc projections. Implications for domestic energy policy and international implications are briefly discussed. (LEW)

  16. Physics of solar activity

    Science.gov (United States)

    Sturrock, Peter A.

    1993-01-01

    The aim of the research activity was to increase our understanding of solar activity through data analysis, theoretical analysis, and computer modeling. Because the research subjects were diverse and many researchers were supported by this grant, a select few key areas of research are described in detail. Areas of research include: (1) energy storage and force-free magnetic field; (2) energy release and particle acceleration; (3) radiation by nonthermal electrons; (4) coronal loops; (5) flare classification; (6) longitude distributions of flares; (7) periodicities detected in the solar activity; (8) coronal heating and related problems; and (9) plasma processes.

  17. Optoelectronics of solar cells

    CERN Document Server

    Smestad, Greg P

    2002-01-01

    With concerns about worldwide environmental security, global warming, and climate change due to emissions of carbon dioxide from the burning of fossil fuels, it is desirable to have a wide range of energy technologies in a nation's portfolio. Photovoltaics, or solar cells, are a viable option as a nonpolluting renewable energy source. This text is designed to be an overview of photovoltaic solar cells for those in the fields of optics and optical engineering, as well as those who are interested in energy policy, economics, and the requirements for efficient photo-to-electric energy conversion.

  18. Solar energy conversion

    CERN Document Server

    Likhtenshtein, Gertz I

    2012-01-01

    Finally filling a gap in the literature for a text that also adopts the chemist?s view of this hot topic, Prof Likhtenshtein, an experienced author and internationally renowned scientist, considers different physical and engineering aspects in solar energy conversion. From theory to real-life systems, he shows exactly which chemical reactions take place when converting light energy, providing an overview of the chemical perspective from fundamentals to molecular harvesting systems and solar cells. This essential guide will thus help researchers in academia and industry better understa

  19. Solar noise storms

    CERN Document Server

    Elgaroy, E O

    2013-01-01

    Solar Noise Storms examines the properties and features of solar noise storm phenomenon. The book also presents some theories that can be used to gain a better understanding of the phenomenon. The coverage of the text includes topics that cover the features and behavior of noise storms, such as the observable features of noise storms; the relationship between noise storms and the observable features on the sun; and ordered behavior of storm bursts in the time-frequency plane. The book also covers the spectrum, polarization, and directivity of noise storms. The text will be of great use to astr

  20. Nanomaterials for solar energy

    KAUST Repository

    Revaprasadu, Neerish

    2013-01-01

    Nanostructured metal chalcogenides of the elements copper, iron, tin, lead and cadmium have attracted interest in their use as colloidal nanocrystal inks for solar cells. Some of these materials have the advantages of being available in abundance and having low toxicity. Developing methods for the combination of the elements to produce binary, ternary and quaternary compounds has dominated research in the field. This chapter will provide the most recent developments (from year 2012 onwards) for the synthesis and use of colloidal nanocrystal inks for solar cell applications. © The Royal Society of Chemistry 2014.

  1. Drainback solar thermal systems

    DEFF Research Database (Denmark)

    Botpaev, R.; Louvet, Y.; Perers, Bengt

    2016-01-01

    Although solar drainback systems have been used for a long time, they are still generating questions regarding smooth functioning. This paper summarises publications on drainback systems and compiles the current knowledge, experiences, and ideas on the technology. The collective research exhibits...... of this technology has been developed, with a brief description of each hydraulic typology. The operating modes have been split into three stages: filling, operation, and draining, which have been studied separately. A difference in the minimal filling velocities for a siphon development in the solar loop has been...

  2. Corrosion resistant solar mirror

    Energy Technology Data Exchange (ETDEWEB)

    Medwick, Paul A.; Abbott, Edward E.

    2016-07-19

    A reflective article includes a transparent substrate having a first major surface and a second major surface. A base coat is formed over at least a portion of the second major surface. A primary reflective coating having at least one metallic layer is formed over at least a portion of the base coat. A protective coating is formed over at least a portion of the primary reflective coating. The article further includes a solar cell and an anode, with the solar cell connected to the metallic layer and the anode.

  3. New Vacuum Solar Telescope

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    With its pure aperture up to 985mm, the New Vacuum Solar Telescope of China (NVST) has become the world's biggest vacuum solar telescope. The main science task of NVST is the high-resolution observation of photosphere and chromosphere including their fine structure of magnetic field on the sun. The NVST was equipped with many new technologies and powerful instruments, such as an adaptive optical system, a polarization analyzer, two vertical spectrographs, a high-resolution image system and a very narrow Ha filter (0.125A).

  4. Passive Solar Heating Residences.

    Science.gov (United States)

    1979-07-01

    temperatures of indes 1, 0, 8, and 7. Figure C-2 shows the rate of solair radiation absorption in node 1 (the prinnary solar heat souirce., the rate of...energy. The heating is basically done by letting the sun’s radiation into a building’s interior, to be stored in some kind of thermal mass or to heat up...solar radiation through south facing windows or clerestroies to be stored in the walls or floor of the house. Thermal storage in a wall or roof allows

  5. Dye solar cell research

    CSIR Research Space (South Africa)

    Cummings, F

    2009-11-01

    Full Text Available stream_source_info Cummings_2009.pdf.txt stream_content_type text/plain stream_size 3362 Content-Encoding UTF-8 stream_name Cummings_2009.pdf.txt Content-Type text/plain; charset=UTF-8 DYE SOLAR CELL RESEARCH Franscious... Cummings Energy and Processes Materials Science and Manufacturing Council for Scientific and Industrial Research P.O. Box 395 Pretoria 0001, South Africa 27 November 2009 CONTENT head2rightBackground head2rightCSIR Dye Solar Cell Research head2...

  6. Solar Air Sampler

    Science.gov (United States)

    1981-01-01

    Nation's first solar-cell-powered air monitoring station was installed at Liberty State Park, New Jersey. Jointly sponsored by state agencies and the Department of Energy, system includes display which describes its operation to park visitors. Unit samples air every sixth day for a period of 24 hours. Air is forced through a glass filter, then is removed each week for examination by the New Jersey Bureau of Air Pollution. During the day, solar cells provide total power for the sampling equipment. Excess energy is stored in a bank of lead-acid batteries for use when needed.

  7. Solar Neutrinos. II. Experimental

    Science.gov (United States)

    Davis, Raymond Jr.

    1964-01-01

    A method is described for observing solar neutrinos from the reaction Cl{sup 37}(nu,e{sup -})Ar{sup 37} in C{sub 2}Cl{sub 4}. Two 5 00-gal tanks of C{sub 2}Cl{sub 4} were placed in a limestone mine (1800 m.w.e.) and the resulting Ar{sup 37} activity induced by cosmic mesons( mu ) was measured to determine the necessary conditions for solar neutrino observations. (R.E.U.)

  8. Solar-neutrino oscillations

    Science.gov (United States)

    Krauss, L.; Wilczek, F.

    1985-01-01

    The theory of oscillations of solar neutrinos is developed as it applies to the electron-recoil spectrum in neutrino-electron scattering. The spectral information obtained by such measurements (as opposed to counting total event rates) is crucial for allowing observation of neutrino oscillations for masses down to 500 neV. In this regard, the effects of different masses and mixing angles, as well as such subtleties as thermal and pressure broadening, finite solar-core size, and variable indices of refraction are investigated.

  9. Purdue Solar Energy Utilization Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Agrawal, Rakesh [Purdue

    2014-01-21

    The objective of this project is to establish and set-up a laboratory that will facilitate research and development of new low-cost and high-efficiency solar energy utilization technologies at Purdue University. The outcome will help spur the creation of solar energy start-up companies and eventually a solar energy industry in Indiana that can help fulfill the growing national demand for solar energy.

  10. Space solar cells - tradeoff analysis

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, M.R. [ISRO Satellite Centre, Bangalore (India). Power Systems Group

    2003-05-15

    This paper summarizes the study that had the objective to tradeoff space solar cells and solar array designs to determine the best choice of solar cell and array technology that would be more beneficial in terms of mass, area and cost for different types of space missions. Space solar cells, which are commercially now available in the market and to be available in the near future, were considered for this trade study. Four solar array designs: rigid, flexible, thin film flexible and concentrator solar arrays were considered for assessment. Performance of the solar cells along with solar array designs were studied for two types of space missions:geo synchronous orbit (GEO) and low earth orbit (LEO) spacecraft. The Solar array designs assumed were to provide 15 kW power for 15 years mission life in GEO and 5 kW power for 5 years mission life in LEO altitudes. To perform tradeoff analysis a spread sheet model was developed that calculates the size, mass and estimates the cost of solar arrays based on different solar cell and array technologies for given set of mission requirements. Comparative performance metrics (W/kg, W/m{sup 2}, kg/m{sup 2}, and $/W) were calculated for all solar arrays studied and compared, at the solar array subsystem level and also at the spacecraft system level. The trade analysis results show that high-efficiency multijunction solar cells bring lot of cost advantages for both types of missions. The trade study also shows that thin film solar cells with moderate efficiency with ultra lightweight flexible array design may become competitive with well-established single crystalline solar cell technologies in the future. (author)

  11. Space solar cells. Tradeoff analysis

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, M. Raja [Power Systems Group, Solar Panels Division, ISRO Satellite Centre, Bangalore 560017 (India)

    2003-05-15

    This paper summarizes the study that had the objective to tradeoff space solar cells and solar array designs to determine the best choice of solar cell and array technology that would be more beneficial in terms of mass, area and cost for different types of space missions. Space solar cells, which are commercially now available in the market and to be available in the near future, were considered for this trade study. Four solar array designs: rigid, flexible, thin film flexible and concentrator solar arrays were considered for assessment. Performance of the solar cells along with solar array designs were studied for two types of space missions: geo synchronous orbit (GEO) and low earth orbit (LEO) spacecraft. The Solar array designs assumed were to provide 15kW power for 15 years mission life in GEO and 5kW power for 5 years mission life in LEO altitudes. To perform tradeoff analysis a spread sheet model was developed that calculates the size, mass and estimates the cost of solar arrays based on different solar cell and array technologies for given set of mission requirements. Comparative performance metrics (W/kg, W/m{sup 2}, kg/m{sup 2}, and $/W) were calculated for all solar arrays studied and compared, at the solar array subsystem level and also at the spacecraft system level. The trade analysis results show that high-efficiency multijunction solar cells bring lot of cost advantages for both types of missions. The trade study also show that thin film solar cells with moderate efficiency with ultra lightweight flexible array design may become competitive with well-established single crystalline solar cell technologies in the future.

  12. Solar thermal system engineering guidebook

    Science.gov (United States)

    Selcuk, M. K.; Bluhm, S. A.

    1983-05-01

    This report presents a graphical methodology for the preliminary evaluation of solar thermal energy plants by Air Force base civil engineers. The report is organized as a Guidebook with worksheets and nomograms provided for rapid estimation of solar collector area, land area, energy output, and thermal power output of a solar thermal plant. Flat plate, evacuated tube, parabolic trough, and parabolic dish solar thermal technologies are considered.

  13. 2010 Solar Technologies Market Report

    Energy Technology Data Exchange (ETDEWEB)

    2011-11-01

    The U.S. Department of Energy (DOE) 2010 Solar Technologies Market Report details the market conditions and trends for photovoltaic (PV) and concentrating solar power (CSP) technologies. Produced by the National Renewable Energy Laboratory (NREL), the report provides a comprehensive overview of the solar electricity market and identifies successes and trends within the market from both global and national perspectives.

  14. Solar energy for the hospital?

    Science.gov (United States)

    1981-01-01

    You can't scrap your boiler and expect solar panels to provide steam for process and heating, but solar systems are cost-effective now for domestic hot water generation, according to a leading solar energy engineering/design/build firm.

  15. Solar energy technical training directory

    Energy Technology Data Exchange (ETDEWEB)

    Corcoleotes, G; Kramer, K; O& #x27; Connor, K

    1979-06-01

    Available solar energy offerings in the technical training area are presented. Institutions are listed alphabetically by state. Each listing includes an institution address and phone number, solar programs or curricula offered, and detailed solar couse information. An alphabetical index of institutions in included. (MHR)

  16. Degradation of CIGS solar cells

    NARCIS (Netherlands)

    Theelen, M.J.

    2015-01-01

    Thin film CIGS solar cells and individual layers within these solar cells have been tested in order to assess their long term stability. Alongside with the execution of standard tests, in which elevated temperatures and humidity levels are used, the solar cells have also been exposed to a combinatio

  17. Program for Paraboloidal Solar Concentrators

    Science.gov (United States)

    Wen, Liang-Chi; O'Brien, Philip

    1987-01-01

    Solar-Concentrator Code for Paraboloidal Dishes (SOLCOL) aids in design and analysis of solar collectors in space station. Calculates quality of solar image and flux distribution on specified target surface. Receiver target is focal plane cylinder, hemisphere, or any arbitrary surface, normals to which supplied. Used to assess optical performance of concentrator. Written in FORTRAN 77.

  18. Angular solar absorptance of absorbers used in solar thermal collectors.

    Science.gov (United States)

    Tesfamichael, T; Wäckelgård, E

    1999-07-01

    The optical characterization of solar absorbers for thermal solar collectors is usually performed by measurement of the spectral reflectance at near-normal angle of incidence and calculation of the solar absorptance from the measured reflectance. The solar absorptance is, however, a function of the angle of incidence of the light impinging on the absorber. The total reflectance of two types of commercial solar-selective absorbers, nickel-pigmented anodized aluminum, and sputtered nickel nickel oxide coated aluminum are measured at angles of incidence from 5 to 80 in the wavelength range 300-2500 nm by use of an integrating sphere. From these measurements the angular integrated solar absorptance is determined. Experimental data are compared with theoretical calculations, and it is found that optical thin-film interference effects can explain the significant difference in solar absorptance at higher angles for the two types of absorbers.

  19. 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...

  20. Solar-heating system

    Science.gov (United States)

    1979-01-01

    Report describes solar modular domestic-hot-water and space-heating system intended for use in small single family dwelling where roof-mounted collectors are not feasible. Contents include design, performance, and hardware specifications for assembly, installation, operation, and maintenance of system.

  1. Solar photonitrosation of cyclohexane

    Energy Technology Data Exchange (ETDEWEB)

    Riffelmann, K.J.; Funken, K.H. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V., Koeln (Germany). Hauptabteilung Energietechnik

    1997-12-31

    The photonitrosation of cyclohexane with nitrosyl chloride (PNC-process) is the central reaction step of photochemical production of {epsilon}-caprolactam. As compared to other, i.e. thermal routes for manufacture of {epsilon}-caprolactam the photochemical synthesis path is the shortest one, economizing the effective use of raw materials by having the highest yield and selectivity. In 1991 the world-wide capacity of {epsilon}-caprolactam was 3.1 mio metric tons/a. Although the photochemical route is most effective as to the materials costs, only 160 000 metric tons (i.e. 5%) were produced via the photochemical path. To provide the light doped high pressure mercury lamps were used. Disadvantages of the conventional PNC-process are strongly corrosive properties of nitrosyl chloride, high power costs and limited lifetime of the lamps. The last two disadvantages may be avoided using sunlight as clean source of photons. A simplified cost study showed that the solar process has a chance to be realized industrially as an alternative to the conventional technique. In this paper results of a project are dealt with aiming at the experimental investigation of the solar PNC-process to demonstrate that cyclohexanone oxime can be produced in a quality as required by the chemical industry. A solar reactor made of titanium was constructed and tested in the high flux solar furnace at the DLR research center, Koeln. Chemical efficiency and selectivity of the reaction, as well as quality of cyclohexanone oxime produced are presented. (orig.)

  2. Properties of solar pores

    NARCIS (Netherlands)

    Sütterlin, Peter

    2001-01-01

    We present the results of an extensive investigation of the properties of solar pores. Spectra of all 4 Stokes parameters of several magnetic sensitive absorption lines as well as Stokes I only spectra of lines with low or vanishing Landéfactor have been observed. An inversion code based on the Leve

  3. Development of Solar Scintillometer

    Indian Academy of Sciences (India)

    Sudhir Kumar Gupta; Shibu K. Mathew; P. Venkatakrishnan

    2006-06-01

    The index of scintillation measurement is a good parameter to compare different sites for image quality or ‘seeing’.We have developed a scintillometer, which is deployed on the high resolution SPAR telescope in the island site of Udaipur Solar Observatory, for the site characterization to specify the proposed MAST (Multi Application Solar Telescope). The scintillometer consists of a miniature telescope, termed as micro telescope (4mm aperture, 15mm focal length) mounted on a drive which tracks the Sun continuously, associated amplifiers and a data acquisition system. A photodiode is used as the detector. The telescope along with detector was obtained from National Solar Observatory (NSO), and is similar to the one used for Advanced Technology Solar Telescope (ATST) site survey. At USO we developed the amplifier and data acquisition system for the scintillometer. A 24-bit analog to digital converter based system was designed, assembled, tested and used as the data acquisition system (DAS). In this paper, we discuss the instrumentation and present the initial results.

  4. Solar 79 Northwest

    Energy Technology Data Exchange (ETDEWEB)

    King, S [ed.

    1979-01-01

    The highlights of the many public programs are described and summaries of plenary session speeches are included. Names, addresses, and solar interest codes of conference registrants are included. Eleven technical papers or summaries are included. A separate citation was prepared for each one. (MHR)

  5. Solar Coronal Plumes

    Directory of Open Access Journals (Sweden)

    Giannina Poletto

    2015-12-01

    Full Text Available Polar plumes are thin long ray-like structures that project beyond the limb of the Sun polar regions, maintaining their identity over distances of several solar radii. Plumes have been first observed in white-light (WL images of the Sun, but, with the advent of the space era, they have been identified also in X-ray and UV wavelengths (XUV and, possibly, even in in situ data. This review traces the history of plumes, from the time they have been first imaged, to the complex means by which nowadays we attempt to reconstruct their 3-D structure. Spectroscopic techniques allowed us also to infer the physical parameters of plumes and estimate their electron and kinetic temperatures and their densities. However, perhaps the most interesting problem we need to solve is the role they cover in the solar wind origin and acceleration: Does the solar wind emanate from plumes or from the ambient coronal hole wherein they are embedded? Do plumes have a role in solar wind acceleration and mass loading? Answers to these questions are still somewhat ambiguous and theoretical modeling does not provide definite answers either. Recent data, with an unprecedented high spatial and temporal resolution, provide new information on the fine structure of plumes, their temporal evolution and relationship with other transient phenomena that may shed further light on these elusive features.

  6. The Solar Convection Spectrum

    Science.gov (United States)

    Bachmann, Kurt T.

    2000-01-01

    I helped to complete a research project with NASA scientists Dr. David Hathaway (my mentor), Rick Bogart, and John Beck from the SOHO/SOI collaboration. Our published paper in 'Solar Physics' was titled 'The Solar Convection Spectrum' (April 2000). Two of my undergraduate students were named on the paper--Gavrav Khutri and Josh Petitto. Gavrav also wrote a short paper for the National Conference of Undergraduate Research Proceedings in 1998 using a preliminary result. Our main result was that we show no evidence of a scale of convection named 'mesogranulation'. Instead, we see only direct evidence for the well-known scales of convection known as graduation and supergranulation. We are also completing work on vertical versus horizontal flow fluxes at the solar surface. I continue to work on phase relationships of solar activity indicators, but I have not yet written a paper with my students on this topic. Along with my research results, I have developed and augmented undergraduate courses at Birmingham-Southern College by myself and with other faculty. We have included new labs and observations, speakers from NASA and elsewhere, new subject material related to NASA and space science. I have done a great deal of work in outreach, mostly as President and other offices in the Birmingham Astronomical Society. My work includes speaking, attracting speakers, giving workshops, and governing.

  7. Solar Photovoltaic Energy.

    Science.gov (United States)

    Ehrenreich, Henry; Martin, John H.

    1979-01-01

    The goals of solar photovoltaic technology in contributing to America's future energy needs are presented in this study conducted by the American Physical Society. Although the time needed for photovoltaics to become popular is several decades away, according to the author, short-range applications are given. (Author/SA)

  8. The Solar Dynamo Zoo

    Science.gov (United States)

    Egeland, Ricky; Soon, Willie; Baliunas, Sallie; Hall, Jeffrey C.; Pevtsov, Alexei A.; Henry, Gregory W.

    2016-07-01

    We present composite time series of Ca II H & K line core emission indices of up to 50 years in length for a set of 27 solar-analog stars (spectral types G0-G5; within 10% of the solar mass) and the Sun. These unique data are available thanks to the long-term dedicated efforts of the Mount Wilson Observatory HK project, the Lowell Observatory Solar-Stellar Spectrograph, and the National Solar Observatory/Air Force Research Laboratory/Sacramento Peak K-line monitoring program. The Ca II H & K emission originates in the lower chromosphere and is strongly correlated with the presence of magnetic plage regions in the Sun. These synoptic observations allow us to trace the patterns long-term magnetic variability and explore dynamo behavior over a wide range of rotation regimes and stellar evolution timescales.In this poster, the Ca HK observations are expressed using the Mount Wilson S-index. Each time series is accompanied by a Lomb-Scargle periodogram, fundemental stellar parameters derived from the Geneva-Copenhagen Survey, and statistics derived from the time series including the median S-index value and seasonal and long-term amplitudes. Statistically significant periodogram peaks are ranked according to a new cycle quality metric. We find that clear, simple, Sun-like cycles are the minority in this sample.

  9. Combined solar unit

    Energy Technology Data Exchange (ETDEWEB)

    Bayramov, R.B.; Nazarova, G.R.; Pivovarova, A.P.; Ushakova, A.D.

    1982-01-01

    In order to improve the effectiveness of using solar energy, the collector containing the loops for heat and cold supply is equipped with a corrugated regenerator installed under the boiler, and the latter is made in the form of a coil arranged at the top of the regenerator crimping.

  10. Polymer tandem solar cells

    NARCIS (Netherlands)

    Hadipour, Afshin

    2007-01-01

    The global demand for energy is expanding continually. Therefore, realization of green power sources are needed since combustion of fossil fuels will have serious consequences for the climate on the Earth. With a photovoltaic device, the solar light can be converted into electricity which is the mos

  11. Transparent solar cell module

    Science.gov (United States)

    Antonides, G. J.; Dillard, P. A.; Fritz, W. M.; Lott, D. P.

    1979-01-01

    Modified solar cell module uses high transmission glass and adhesives, and heat dissipation to boost power per unit area by 25% (9.84% efficiency based on cell area at 60 C and 100 mW/sq cm flux). Design is suited for automatic production and is potentially more cost effective.

  12. Solar Radiation Alert System

    Science.gov (United States)

    2009-03-01

    18 December 2007). 19. HAARP , The Hgh Frequency Actve Auroral Research Program. Glossary of Solar and Geophysical Terms. Avalable at...www.haarp.alaska.edu/ haarp /glos.html (accessed: 4 September 2007). 13 20. IZMIRAN. Pushkov Insttute of Terrestral Mag- netsm, Ionosphere and Radowave

  13. Solar Sea Power

    Science.gov (United States)

    Zener, Clarence

    1976-01-01

    In their preoccupation with highly complex new energy systems, scientists and statesmen may be overlooking the possibilities of Ocean Thermal Energy Conversion (OTEC). That is the view of a Carnegie-Mellon University physicist who is in the forefront of solar sea power investigation. (Author/BT)

  14. Solar Fuel Generator

    Science.gov (United States)

    Lewis, Nathan S. (Inventor); West, William C. (Inventor)

    2017-01-01

    The disclosure provides conductive membranes for water splitting and solar fuel generation. The membranes comprise an embedded semiconductive/photoactive material and an oxygen or hydrogen evolution catalyst. Also provided are chassis and cassettes containing the membranes for use in fuel generation.

  15. Solar energy conversion

    OpenAIRE

    Crabtree, George W.; Lewis, Nathan S.

    2007-01-01

    If solar energy is to become a practical alternative to fossil fuels, we must have efficient ways to convert photons into electricity, fuel, and heat. The need for better conversion technologies is a driving force behind many recent developments in biology, materials, and especially nanoscience.

  16. NASA Facts, Solar Cells.

    Science.gov (United States)

    National Aeronautics and Space Administration, Washington, DC.

    The design and function of solar cells as a source of electrical power for unmanned space vehicles is described in this pamphlet written for high school physical science students. The pamphlet is one of the NASA Facts Science Series (each of which consists of four pages) and is designed to fit in the standard size three-ring notebook. Review…

  17. Integrating a solar chimney

    NARCIS (Netherlands)

    Akerboom, R.; Gkerou, V.

    2014-01-01

    This "designers' manual" is made during the TIDO-course AR0533 Innovation & Sustainability. This designer’s manual presents an overview of integration methods of a solar chimney during refurbishment of office buildings and describes step by step the design methods. A lot of research has been made t

  18. Nanoimprinted polymer solar cell.

    Science.gov (United States)

    Yang, Yi; Mielczarek, Kamil; Aryal, Mukti; Zakhidov, Anvar; Hu, Walter

    2012-04-24

    Among the various organic photovoltaic devices, the conjugated polymer/fullerene approach has drawn the most research interest. The performance of these types of solar cells is greatly determined by the nanoscale morphology of the two components (donor/acceptor) and the molecular orientation/crystallinity in the photoactive layer. A vertically bicontinuous and interdigitized heterojunction between donor and acceptor has been regarded as one of the ideal structures to enable both efficient charge separation and transport. Synergistic control of polymer orientation in the nanostructured heterojunction is also critical to improve the performance of polymer solar cells. Nanoimprint lithography has emerged as a new approach to simultaneously control both the heterojunction morphology and polymer chains in organic photovoltaics. Currently, in the area of nanoimprinted polymer solar cells, much progress has been achieved in the fabrication of nanostructured morphology, control of molecular orientation/crystallinity, deposition of acceptor materials, patterned electrodes, understanding of structure-property correlations, and device performance. This review article summarizes the recent studies on nanoimprinted polymer solar cells and discusses the outstanding challenges and opportunities for future work.

  19. Simple, economical solar collector

    Science.gov (United States)

    Anthony, K.

    1979-01-01

    Hot air solar collector designed for economy and simplicity is assembled from only three parts: (1) molded urethane foam body, (2) flat sheet metal collector panel and (3) transparent cover. Large arrays may be assembled by inserting male fittings of each collector into female fitting of adjacent collector.

  20. Photocatalysis: Plasmonic solar desalination

    Science.gov (United States)

    Liu, Tianyu; Li, Yat

    2016-06-01

    The sustainability of many existing desalination technologies is questionable. Plasmon-mediated solar desalination has now been demonstrated for the first time, using an aluminium structure that absorbs photons spanning the 200 nm to 2,500 nm wavelength range, and is both cheap and 'clean'.

  1. Solar Photovoltaic Energy.

    Science.gov (United States)

    Ehrenreich, Henry; Martin, John H.

    1979-01-01

    The goals of solar photovoltaic technology in contributing to America's future energy needs are presented in this study conducted by the American Physical Society. Although the time needed for photovoltaics to become popular is several decades away, according to the author, short-range applications are given. (Author/SA)

  2. The Nano Solar Case

    DEFF Research Database (Denmark)

    Hollensen, Svend

    2011-01-01

    ISO PAINT Nordic A/S produces roof coatings, facade painting as well as specialised products for surface treatments. The company decided that they would develop a nano solar ICT based project having the capacity to change the whole cost structure of a building, for example by a nano roof coating...

  3. Photoelectrochemical Solar Cells.

    Science.gov (United States)

    McDevitt, John T.

    1984-01-01

    This introduction to photoelectrochemical (PEC) cells reviews topics pertaining to solar energy conversion and demonstrates the ease with which a working PEC cell can be prepared with n-type silicon as the photoanode and a platinum counter electrode (both immersed in ethanolic ferrocene/ferricenium solutions). Experiments using the cell are…

  4. Simulating solar MHD

    Directory of Open Access Journals (Sweden)

    M. Schüssler

    Full Text Available Two aspects of solar MHD are discussed in relation to the work of the MHD simulation group at KIS. Photospheric magneto-convection, the nonlinear interaction of magnetic field and convection in a strongly stratified, radiating fluid, is a key process of general astrophysical relevance. Comprehensive numerical simulations including radiative transfer have significantly improved our understanding of the processes and have become an important tool for the interpretation of observational data. Examples of field intensification in the solar photosphere ('convective collapse' are shown. The second line of research is concerned with the dynamics of flux tubes in the convection zone, which has far-reaching implications for our understanding of the solar dynamo. Simulations indicate that the field strength in the region where the flux is stored before erupting to form sunspot groups is of the order of 105 G, an order of magnitude larger than previous estimates based on equipartition with the kinetic energy of convective flows.

    Key words. Solar physics · astrophysics and astronomy (photosphere and chromosphere; stellar interiors and dynamo theory; numerical simulation studies.

  5. The Solar Dynamo

    Science.gov (United States)

    Hathaway, David H.

    1998-01-01

    The solar dynamo is the process by which the Sun's magnetic field is generated through the interaction of the field with convection and rotation. In this, it is kin to planetary dynamos and other stellar dynamos. Although the precise mechanism by which the Sun generates its field remains poorly understood despite decades of theoretical and observational work, recent advances suggest that solutions to this solar dynamo problem may be forthcoming. Two basic processes are involved in dynamo activity. When the fluid stresses dominate the magnetic stresses (high plasma beta = 8(pi)rho/B(sup 2)), shear flows can stretch magnetic field lines in the direction of the shear (the "alpha effect") and helical flows can lift and twist field lines into orthogonal planes (the "alpha effect"). These two processes can be active anywhere in the solar convection zone but with different results depending upon their relative strengths and signs. Little is known about how and where these processes occur. Other processes, such as magnetic diffusion and the effects of the fine scale structure of the solar magnetic field, pose additional problems.

  6. Solar fuel generator

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, Nathan S.; West, William C.

    2017-01-17

    The disclosure provides conductive membranes for water splitting and solar fuel generation. The membranes comprise an embedded semiconductive/photoactive material and an oxygen or hydrogen evolution catalyst. Also provided are chassis and cassettes containing the membranes for use in fuel generation.

  7. Probing the Solar System

    Science.gov (United States)

    Wilkinson, John

    2013-01-01

    Humans have always had the vision to one day live on other planets. This vision existed even before the first person was put into orbit. Since the early space missions of putting humans into orbit around Earth, many advances have been made in space technology. We have now sent many space probes deep into the Solar system to explore the planets and…

  8. Junior Solar Sprint.

    Science.gov (United States)

    O'Shea, Aisling

    1997-01-01

    Reports on a project sponsored by the United States Department of Energy (DOE) that engages students in building solar cars in groups with kits that include a three volt panel. The design and engineering decisions are made by the students using pertinent information. (DDR)

  9. Solar System Update

    CERN Document Server

    Blondel, Philippe

    2006-01-01

    This book, the first in a series of forthcoming volumes, consists of topical and timely reviews of a number of carefully selected topics in solar systemn science. Contributions, in form of up-to-date reviews, are mainly aimed at professional astronomers and planetary scientists wishing to inform themselves about progress in fields closely related to their own field of expertise.

  10. Solar concentrator/absorber

    Science.gov (United States)

    Von Tiesenhausen, G. F.

    1976-01-01

    Collector/energy converter, consisting of dual-slope optical concentrator and counterflow thermal energy absorber, is attached to multiaxis support structure. Efficient over wide range of illumination levels, device may be used to generate high temperature steam, serve as solar powered dryer, or power absorption cycle cooler.

  11. Probing the Solar System

    Science.gov (United States)

    Wilkinson, John

    2013-01-01

    Humans have always had the vision to one day live on other planets. This vision existed even before the first person was put into orbit. Since the early space missions of putting humans into orbit around Earth, many advances have been made in space technology. We have now sent many space probes deep into the Solar system to explore the planets and…

  12. The New Solar System

    Science.gov (United States)

    Wilkinson, John

    2009-01-01

    Since 2006, the details of bodies making up our solar system have been revised. This was largely as a result of new discoveries of a number of planet-like objects beyond the orbit of Pluto. The International Astronomical Union redefined what constituted a planet and established two new classifications--dwarf planets and plutoids. As a result, the…

  13. Solar Magnetic Fields

    CERN Document Server

    Hood, Alan W

    2011-01-01

    This review provides an introduction to the generation and evolution of the Sun's magnetic field, summarising both observational evidence and theoretical models. The eleven year solar cycle, which is well known from a variety of observed quantities, strongly supports the idea of a large-scale solar dynamo. Current theoretical ideas on the location and mechanism of this dynamo are presented. The solar cycle influences the behaviour of the global coronal magnetic field and it is the eruptions of this field that can impact on the Earth's environment. These global coronal variations can be modelled to a surprising degree of accuracy. Recent high resolution observations of the Sun's magnetic field in quiet regions, away from sunspots, show that there is a continual evolution of a small-scale magnetic field, presumably produced by small-scale dynamo action in the solar interior. Sunspots, a natural consequence of the large-scale dynamo, emerge, evolve and disperse over a period of several days. Numerical simulation...

  14. Solar Thermal Power.

    Science.gov (United States)

    McDaniels, David K.

    The different approaches to the generation of power from solar energy may be roughly divided into five categories: distributed collectors; central receivers; biomass; ocean thermal energy conversion; and photovoltaic devices. The first approach (distributed collectors) is the subject of this module. The material presented is designed to…

  15. The New Solar System

    Science.gov (United States)

    Wilkinson, John

    2009-01-01

    Since 2006, the details of bodies making up our solar system have been revised. This was largely as a result of new discoveries of a number of planet-like objects beyond the orbit of Pluto. The International Astronomical Union redefined what constituted a planet and established two new classifications--dwarf planets and plutoids. As a result, the…

  16. TRMM Solar Array Panels

    Science.gov (United States)

    1998-01-01

    This final report presents conclusions/recommendations concerning the TRMM Solar Array; deliverable list and schedule summary; waivers and deviations; as-shipped performance data, including flight panel verification matrix, panel output detail, shadow test summary, humidity test summary, reverse bias test panel; and finally, quality assurance summary.

  17. Solar imaging vector magnetograph

    Science.gov (United States)

    Canfield, Richard C.

    1993-01-01

    This report describes an instrument which has been constructed at the University of Hawaii to make observations of the magnetic field in solar active regions. Detailed knowledge of active region magnetic structures is crucial to understanding many solar phenomena, because the magnetic field both defines the morphology of structures seen in the solar atmosphere and is the apparent energy source for solar flares. The new vector magnetograph was conceived in response to a perceived discrepancy between the capabilities of X ray imaging telescopes to be operating during the current solar maximum and those of existing magnetographs. There were no space-based magnetographs planned for this period; the existing ground-based instruments variously suffered from lack of sensitivity, poor time resolution, inadequate spatial resolution or unreliable sites. Yet the studies of flares and their relationship to the solar corona planned for the 1991-1994 maximum absolutely required high quality vector magnetic field measurements. By 'vector' measurements we mean that the observation attempts to deduce the complete strength and direction of the field at the measurement site, rather than just the line of sight component as obtained by a traditional longitudinal magnetograph. Knowledge of the vector field permits one to calculate photospheric electric currents, which might play a part in heating the corona, and to calculate energy stored in coronal magnetic fields as the result of such currents. Information about the strength and direction of magnetic fields in the solar atmosphere can be obtained in a number of ways, but quantitative data is best obtained by observing Zeeman-effect polarization in solar spectral lines. The technique requires measuring the complete state of polarization at one or more wavelengths within a magnetically sensitive line of the solar spectrum. This measurement must be done for each independent spatial point for which one wants magnetic field data. All the

  18. Simulate a ‘Sun’ for Solar Research : A Literature Review of Solar Simulator Technology

    OpenAIRE

    Wang, Wujun; Laumert, Björn

    2014-01-01

    The solar simulator is the key facility for indoor research of solar PV cells, solar heat collectors, space craft and CSP systems. This paper classifies the four types of solar simulators based on their characteristics and their design objects: space solar simulator, standard PV cell testing solar simulator, collector testing solar simulator and high-flux solar simulator. The review of solar simulator developments is mainly based on the developments of light sources and optical concentrators....

  19. How to use solar energy in the home and garden? Instructions and suggestions for easy self-construction of solar-powered systems: garden lighting, fountains, solar accumulators and solar motors; Wie nutze ich Solarenergie in Haus und Garten?. Bauanleitungen und Anregungen zum leichten Selbstbau von Solaranlagen wie z.B. Solar-Gartenbeleuchtung, Solar-Springbrunnen, Solar-Akkumulatoren, Solar-Elektromotoren

    Energy Technology Data Exchange (ETDEWEB)

    Hanus, B.

    1995-08-01

    The book reports on solar energy utilization: - solar energy and photovoltaics, - solar cell modules for self-construction, - self-sufficient solar power supply, - solar-powered pumps and engines, - ventilation and cooling using solar power, - heating using solar power, - garden lighting using solar power. (HW) [Deutsch] Das Buch berichtet ueber die Nutzung von Solarenergie: - Solarenergie und Photovoltaic; - Solarzellenmodule in Selbstbau; - Selbstversorgung mit Solarstrom; - Solar-Pumpen und -Motoren; - Lueften und Kuehlung mit Solarstrom; - Heizen mit Solarstrom; - Gartenbeleuchtung mit Solarstrom. (orig.)

  20. Implementing Solar Technologies at Airports

    Energy Technology Data Exchange (ETDEWEB)

    Kandt, A.; Romero, R.

    2014-07-01

    Federal agencies, such as the Department of Defense and Department of Homeland Security, as well as numerous private entities are actively pursuing the installation of solar technologies to help reduce fossil fuel energy use and associated emissions, meet sustainability goals, and create more robust or reliable operations. One potential approach identified for siting solar technologies is the installation of solar energy technologies at airports and airfields, which present a significant opportunity for hosting solar technologies due to large amounts of open land. This report focuses largely on the Federal Aviation Administration's (FAA's) policies toward siting solar technologies at airports.

  1. Review of solar radiation utilizability

    Science.gov (United States)

    Klein, S. A.; Beckman, W. A.

    1984-11-01

    A development history is presented for the concept and methodology of solar radiation 'utilizability', which is defined as the fraction of solar radiation that is incident on a surface exceeding a specified threshold or critical level. The concept, which was initially applied to flat plate solar collector thermal performance calculations, has more recently been applied to systems with concentrating collectors as well as to passive and photovoltaic systems. The utilizability function also contains information about operating times through its derivative with respect to critical level. Existing utilizability correlations provide a simple and elegant means of estimating the long term effect of solar radiation on any solar process.

  2. Effect of solar electron temperature on pep solar neutrino flux in the chlorine solar neutrino experiment and the gallium solar neutrino experiment

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The rate of the electron-capture reaction of proton,p+e-+p→2H+ve , is calculated considering the temperature of solar electron in the solar center instead of that of solar ion. When the solar electron temperature is two times higher than the solar ion temperature in the solar center, the capture rate pep solar neutrino predicted by the standard solar model (SSM) is decreased to (0.16±0.01) SNU from (0.22±0.01) SNU in the chlorine solar neutrino experiment, and decreased to 2.19 SNU from 3.0 SNU in the gallium solar neutrino experiment.

  3. Solar Variability and Planetary Climates

    CERN Document Server

    Calisesi, Y; Gray, L; Langen, J; Lockwood, M

    2007-01-01

    Variations in solar activity, as revealed by variations in the number of sunspots, have been observed since ancient times. To what extent changes in the solar output may affect planetary climates, though, remains today more than ever a subject of controversy. In 2000, the SSSI volume on Solar Variability and Climate reviewed the to-date understanding of the physics of solar variability and of the associated climate response. The present volume on Solar Variability and Planetary Climates provides an overview of recent advances in this field, with particular focus at the Earth's middle and lower atmosphere. The book structure mirrors that of the ISSI workshop held in Bern in June 2005, the collection of invited workshop contributions and of complementary introductory papers synthesizing the current understanding in key research areas such as middle atmospheric processes, stratosphere-troposphere dynamical coupling, tropospheric aerosols chemistry, solar storm influences, solar variability physics, and terrestri...

  4. Ion Acceleration in Solar Flares Determined by Solar Neutron Observations

    Science.gov (United States)

    Watanabe, K.; Solar Neutron Observation Group

    2013-05-01

    Large amounts of particles can be accelerated to relativistic energy in association with solar flares and/or accompanying phenomena (e.g., CME-driven shocks), and they sometimes reach very near the Earth and penetrate the Earth's atmosphere. These particles are observed by ground-based detectors (e.g., neutron monitors) as Ground Level Enhancements (GLEs). Some of the GLEs originate from high energy solar neutrons which are produced in association with solar flares. These neutrons are also observed by ground-based neutron monitors and solar neutron telescopes. Recently, some of the solar neutron detectors have also been operating in space. By observing these solar neutrons, we can obtain information about ion acceleration in solar flares. Such neutrons were observed in association with some X-class flares in solar cycle 23, and sometimes they were observed by two different types of detectors. For example, on 2005 September 7, large solar neutron signals were observed by the neutron monitor at Mt. Chacaltaya in Bolivia and Mexico City, and by the solar neutron telescopes at Chacaltaya and Mt. Sierra Negra in Mexico in association with an X17.0 flare. The neutron signal continued for more than 20 minutes with high statistical significance. Intense gamma-ray emission was also registered by INTEGRAL, and by RHESSI during the decay phase. We analyzed these data using the solar-flare magnetic-loop transport and interaction model of Hua et al. (2002), and found that the model could successfully fit the data with intermediate values of loop magnetic convergence and pitch angle scattering parameters. These results indicate that solar neutrons were produced at the same time as the gamma-ray line emission and that ions were continuously accelerated at the emission site. In this paper, we introduce some of the solar neutron observations in solar cycle 23, and discuss the tendencies of the physical parameters of solar neutron GLEs, and the energy spectrum and population of the

  5. Solar Eruptive Events

    Science.gov (United States)

    Holman, Gordon D.

    2012-01-01

    It s long been known that the Sun plays host to the most energetic explosions in the solar system. But key insights into the forms that energy takes have only recently become available. Solar flares have been phenomena of both academic and practical interest since their discovery in 1859. From the academic point of view, they are the nearest events for studying the explosive release of energy in astrophysical magnetized plasmas. From the practical point of view, they disrupt communication channels on Earth, from telegraph communications in 1859 to radio and television signals today. Flares also wreak havoc on the electrical power grid, satellite operations, and GPS signals, and energetic charged particles and radiation are dangerous to passengers on high-altitude polar flights and to astronauts. Flares are not the only explosive phenomena on the Sun. More difficult to observe but equally energetic are the large coronal mass ejections (CMEs), the ejection of up to ten billion tons of magnetized plasma into the solar wind at speeds that can exceed 1000 km/s. CMEs are primarily observed from the side, with coronagraphs that block out the bright disk of the Sun and lower solar atmosphere so that light scattered from the ejected mass can be seen. Major geomagnetic storms are now known to arise from the interaction of CMEs with Earth's magnetosphere. Solar flares are observed without CMEs, and CMEs are observed without flares. The two phenomena often occur together, however, and almost always do in the case of large flares and fast CMEs. The term solar eruptive event refers to the combination of a flare and a CME. Solar eruptive events generate a lot of heat: They can heat plasma to temperatures as high at 50 million Kelvin, producing radiation across the electromagnetic spectrum. But that s not all. A fascinating aspect of solar eruptive events is the acceleration of electrons and ions to suprathermal often relativistic energies. The accelerated particles are primarily

  6. 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.)

  7. Solar Sources of $^{3}$He-rich Solar Energetic Particle Events in Solar Cycle 24

    OpenAIRE

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

    2015-01-01

    Using high-cadence extreme-ultraviolet (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 (SEP) events at $\\lesssim$1 MeV nucleon$^{-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 observ...

  8. COMPOSITION OF THE SOLAR CORONA, SOLAR WIND, AND SOLAR ENERGETIC PARTICLES

    Energy Technology Data Exchange (ETDEWEB)

    Schmelz, J. T. [Physics Department, University of Memphis, Memphis, TN 38152 (United States); Reames, D. V. [IPST, University of Maryland, College Park, MD 20742 (United States); Von Steiger, R. [ISSI, Hallerstrasse 6, 3012 Bern (Switzerland); Basu, S., E-mail: jschmelz@memphis.edu [Department of Astronomy, Yale University, P.O. Box 208101, New Haven, CT 06520 (United States)

    2012-08-10

    Along with temperature and density, the elemental abundance is a basic parameter required by astronomers to understand and model any physical system. The abundances of the solar corona are known to differ from those of the solar photosphere via a mechanism related to the first ionization potential of the element, but the normalization of these values with respect to hydrogen is challenging. Here, we show that the values used by solar physicists for over a decade and currently referred to as the 'coronal abundances' do not agree with the data themselves. As a result, recent analysis and interpretation of solar data involving coronal abundances may need to be revised. We use observations from coronal spectroscopy, the solar wind, and solar energetic particles as well as the latest abundances of the solar photosphere to establish a new set of abundances that reflect our current understanding of the coronal plasma.

  9. Solar Stirling system development

    Science.gov (United States)

    Stearns, J. W., Jr.; Won, Y. S.; Poon, P. T.; Das, R.; Chow, E. Y.

    1979-01-01

    A low-cost, high-efficiency dish-Stirling solar thermal-electric power system is being developed for test in 1981. System components are the solar concentrator, receiver, fossil fuel combustor, thermal energy storage (TES), engine-generator, and power processing. System conceptualization is completed and design is in progress. Two receiver alternatives are being evaluated, a direct-coupled receiver-engine configuration with no TES and a heat pipe receiver with TES. System cost projections are being made. Goals for the system development task are (1) to develop an advanced dish-Stirling technology, utilizing a team of industrial contractors, (2) to demonstrate that technology at the system level, and (3) to determine how to achieve low production cost.

  10. Passive solar construction handbook

    Energy Technology Data Exchange (ETDEWEB)

    Levy, E.; Evans, D.; Gardstein, C.

    1981-08-01

    Many of the basic elements of passive solar design are reviewed. The unique design constraints presented in passive homes are introduced and many of the salient issues influencing design decisions are described briefly. Passive solar construction is described for each passive system type: direct gain, thermal storage wall, attached sunspace, thermal storage roof, and convective loop. For each system type, important design and construction issues are discussed and case studies illustrating designed and built examples of the system type are presented. Construction details are given and construction and thermal performance information is given for the materials used in collector components, storage components, and control components. Included are glazing materials, framing systems, caulking and sealants, concrete masonry, concrete, brick, shading, reflectors, and insulators. The Load Collector Ratio method for estimating passive system performance is appended, and other analysis methods are briefly summarized. (LEW)

  11. The solar element

    DEFF Research Database (Denmark)

    Kragh, Helge

    2009-01-01

    Apart from hydrogen, helium is the most abundant chemical element in the universe, and yet it was only discovered on the Earth in 1895. Its early history is unique because it encompasses astronomy as well as chemistry, two sciences which the spectroscope brought into contact during the second half...... of the nineteenth century. In the modest form of a yellow spectral line known as D3, 'helium' was sometimes supposed to exist in the Sun's atmosphere, an idea which is traditionally ascribed to J. Norman Lockyer. Did Lockyer discover helium as a solar element? How was the suggestion received by chemists, physicists...... elements might be different. The complex story of how helium became established as both a solar and terrestrial element involves precise observations as well as airy speculations. It is a story that is unique among the discovery histories of the chemical elements....

  12. Solar variability and clouds

    CERN Document Server

    Kirkby, Jasper

    2000-01-01

    Satellite observations have revealed a surprising imprint of the 11- year solar cycle on global low cloud cover. The cloud data suggest a correlation with the intensity of Galactic cosmic rays. If this apparent connection between cosmic rays and clouds is real, variations of the cosmic ray flux caused by long-term changes in the solar wind could have a significant influence on the global energy radiation budget and the climate. However a direct link between cosmic rays and clouds has not been unambiguously established and, moreover, the microphysical mechanism is poorly understood. New experiments are being planned to find out whether cosmic rays can affect cloud formation, and if so how. (37 refs).

  13. A solar energy collector

    Energy Technology Data Exchange (ETDEWEB)

    Vasilyev, L.L.; Avakyan, Yu V.; Dabagyan, T.N.; Grakovich, L.P.; Khustalev, D.K.; Morgun, V.A.; Vartanyan, A.V.

    1984-01-01

    During collector operation, solar emission is absorbed by the evaporator section of the heating tube; the degree of blackness of the forward wall of the section is increased significantly by the use of corrugations in this section. Boiling of the working fluid in the longitudinal slotted channels is accompanied by outbursts of the steam fluid mixture in the direction of the forward wall, resulting in wetting of the longitudinal corrugation on this wall. In this solar collector, there is a continuous flow of the working fluid onto the internal surface of the leading wall of the evaporation section of the heat tube; the working fluid evaporation process is accelerated by the spraying resulting from the popping of vapor bubbles.

  14. Characterization of solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Haerkoenen, J.; Tuominen, E.; Nybergh, K.; Ezer, Y.; Yli-Koski, M.; Sinkkonen, J. [Helsinki Univ. of Technology (Finland). Dept. of Electrical and Communications Engineering

    1998-12-31

    Photovoltaic research began at the Electron Physics Laboratory of the Helsinki University of Tehnology in 1993, when the laboratory joined the national NEMO 2 research program. During the early stages of the photovoltaic research the main objective was to establish necessary measurement and characterisation routines, as well as to develop the fabrication process. The fabrication process development work has been supported by characterisation and theoretical modelling of the solar cells. Theoretical investigations have been concerned with systematic studies of solar cell parameters, such as diffusion lengths, surface recombination velocities and junction depths. The main result of the modelling and characterisation work is a method which is based on a Laplace transform of the so-called spatial collection efficiency function of the cell. The basic objective of the research has been to develop a fabrication process cheap enough to be suitable for commercial production

  15. Quantum Dot Solar Cells

    Science.gov (United States)

    Raffaelle, Ryne P.; Castro, Stephanie L.; Hepp, Aloysius; Bailey, Sheila G.

    2002-01-01

    We have been investigating the synthesis of quantum dots of CdSe, CuInS2, and CuInSe2 for use in an intermediate bandgap solar cell. We have prepared a variety of quantum dots using the typical organometallic synthesis routes pioneered by Bawendi, et. al., in the early 1990's. However, unlike previous work in this area we have also utilized single-source precursor molecules in the synthesis process. We will present XRD, TEM, SEM and EDS characterization of our initial attempts at fabricating these quantum dots. Investigation of the size distributions of these nanoparticles via laser light scattering and scanning electron microscopy will be presented. Theoretical estimates on appropriate quantum dot composition, size, and inter-dot spacing along with potential scenarios for solar cell fabrication will be discussed.

  16. Probabilities for Solar Siblings

    Science.gov (United States)

    Valtonen, Mauri; Bajkova, A. T.; Bobylev, V. V.; Mylläri, A.

    2015-02-01

    We have shown previously (Bobylev et al. Astron Lett 37:550-562, 2011) that some of the stars in the solar neighborhood today may have originated in the same star cluster as the Sun, and could thus be called Solar Siblings. In this work we investigate the sensitivity of this result to galactic models and to parameters of these models, and also extend the sample of orbits. There are a number of good candidates for the sibling category, but due to the long period of orbit evolution since the break-up of the birth cluster of the Sun, one can only attach probabilities of membership. We find that up to 10 % (but more likely around 1 %) of the members of the Sun's birth cluster could be still found within 100 pc from the Sun today.

  17. Probabilities for Solar Siblings

    CERN Document Server

    Valtonen, M; Bobylev, V V; Myllari, A

    2015-01-01

    We have shown previously (Bobylev et al 2011) that some of the stars in the Solar neighborhood today may have originated in the same star cluster as the Sun, and could thus be called Solar Siblings. In this work we investigate the sensitivity of this result to Galactic models and to parameters of these models, and also extend the sample of orbits. There are a number of good candidates for the Sibling category, but due to the long period of orbit evolution since the break-up of the birth cluster of the Sun, one can only attach probabilities of membership. We find that up to 10% (but more likely around 1 %) of the members of the Sun's birth cluster could be still found within 100 pc from the Sun today.

  18. Terrestrial solar modules

    Science.gov (United States)

    Sampson, W.; Olah, S.

    Processing methods and materials for the fabrication of solar cell modules are reviewed. It is noted that current production favors copper, particularly in mesh form, as the cell interconnect material due to suitability for stress relief configurations to offset the effects of thermal expansion and deficiencies in the bond between copper and Si. Ethylene vinyl/acetate is preferred to polyvinyl butyral as an encapsulant because it is also a dry film and adheres at low temperature without requiring a pressure bond. The thermal cycling parameters have been set at -40 to 90 C, and tempered low iron, high transmission, water white glass is used as the superstrate. A conceptual design for an automated production of the encapsulated cells is outlined, including the ability to make front and back interconnects and achieve accurate soldering due to the precise location of the solar cells in the process.

  19. The Solar Telescope GREGOR

    Science.gov (United States)

    Volkmer, R.

    2008-09-01

    During the last years the new 1.5m solar telescope GREGOR was assembled at Izania on Tenerife, Spain. The telescope is designed for high-precision measurements of the magnetic field in the solar photosphere and chromosphere with a resolution of 70km on the Sun. The telescope concept offers also high resolution stellar spectroscopy. The telescope is build by a consortium of the Kiepenheuer-Institut für Sonnenphysik, the Astrophysikalische Institut Potsdam, the Institut für Astrophysik Göttingen, Max-Plank-Institut für Sonnensystemforschung and additional international Partners. The telescope is a complete open structure with active cooled main mirror. High performance post-focus instruments in the visible and near IR wavelength acquire high resolution spectra with 2 dimensional spatial resolution and polarimetric information. The commissioning of the telescope will start in 2008 to allow first science observations at the end of 2009.

  20. Solar homes in Apeldoorn

    Energy Technology Data Exchange (ETDEWEB)

    Ogink, J.; Heimeriks, J.; Blokpoel, H.

    1984-11-01

    As part of the research into applications of alternative energy VEG-Gasinstituut had equipped four dwellings with solar collectors, linked to the gas energy system. The purpose of this project was to examine the technical feasibility and to gain an impression of possible savings. This article first discusses the starting points for the solar installation design, then gives details about the energy system and the dwellings. Next the operation of the installations in practice is discussed. The conclusion is that apart from a few minor troubles the installations have operated satisfactorily, though they are capable of improvement based on the experiences. The installations which during the measuring period (April 1981 through December 1983) have supplied on the average about 25% of the required energy, would after improvements be capable of providing for 30-40% of the heat demands.

  1. Electromagnetically Clean Solar Arrays

    Science.gov (United States)

    Stem, Theodore G.; Kenniston, Anthony E.

    2008-01-01

    The term 'electromagnetically clean solar array' ('EMCSA') refers to a panel that contains a planar array of solar photovoltaic cells and that, in comparison with a functionally equivalent solar-array panel of a type heretofore used on spacecraft, (1) exhibits less electromagnetic interferences to and from other nearby electrical and electronic equipment and (2) can be manufactured at lower cost. The reduction of electromagnetic interferences is effected through a combination of (1) electrically conductive, electrically grounded shielding and (2) reduction of areas of current loops (in order to reduce magnetic moments). The reduction of cost is effected by designing the array to be fabricated as a more nearly unitary structure, using fewer components and fewer process steps. Although EMCSAs were conceived primarily for use on spacecraft they are also potentially advantageous for terrestrial applications in which there are requirements to limit electromagnetic interference. In a conventional solar panel of the type meant to be supplanted by an EMCSA panel, the wiring is normally located on the back side, separated from the cells, thereby giving rise to current loops having significant areas and, consequently, significant magnetic moments. Current-loop geometries are chosen in an effort to balance opposing magnetic moments to limit far-0field magnetic interactions, but the relatively large distances separating current loops makes full cancellation of magnetic fields problematic. The panel is assembled from bare photovoltaic cells by means of multiple sensitive process steps that contribute significantly to cost, especially if electomagnetic cleanliness is desired. The steps include applying a cover glass and electrical-interconnect-cell (CIC) sub-assemble, connecting the CIC subassemblies into strings of series-connected cells, laying down and adhesively bonding the strings onto a panel structure that has been made in a separate multi-step process, and mounting the

  2. COLOR- SENSITIZED SOLAR ELEMENTS

    Directory of Open Access Journals (Sweden)

    Gish R. A.

    2016-05-01

    Full Text Available Photovoltaic devices are a promising solution to the energy crisis, because they generate electricity directly from sunlight, without producing CO2. While color-sensitized batteries are the most studied element, mainly due to its low cost and high efficiency solar energy conversion into electricity. Until recently, the color-sensitized solar cells performance was less than 1%, however, the use of titanium dioxide as the anode material have greatly raised their efficiency. The advantages of titanium dioxide is primarily in the low cost, but its use provides high light capture efficiency, with external quantum efficiency (efficiency incident photon - charge, usually in the range of 60-90% using nanocrystal forms in comparison with

  3. The Solar Development Corporation

    Energy Technology Data Exchange (ETDEWEB)

    Singer, C.E.

    1997-12-01

    This paper describes a proposed stand alone company, the Solar Development Corporation (SDC), to be a business development and financing entity for photovoltaic operations with the potential to be commercially sustainable. SDC will have a fully integrated policy advocacy link to the World Bank. SDC will define target countries where the potential exists for significant early market expansion. In those countries it will provide: market and business development services that will accelerate the growth of private firms and deepen the penetration of Solar Home Systems (SHS) and other rural PV applications in the market; and access to pre-commercial and parallel financing for private firms to (1) expand their capability in PV distribution businesses, and (2) strengthen their ability to provide credit to end users. SDC itself will not engage in direct financing of the final consumer. It is intended that as far as possible SDC`s finance will be provided in parallel with financing from Financial Intermediaries.

  4. Advances in solar sailing

    CERN Document Server

    Third International Symposium on Solar Sailing

    2014-01-01

    Hosted by the Advanced Space Concepts Laboratory within the department of Mechanical and Aerospace Engineering of the University of Strathclyde, the third International Symposium on Solar Sailing was held in McCance Building at 16 Richmond Street, Glasgow, between 11 and 13 June 2013. The symposium attracted over 90 delegates from19 different counties, bringing together international experts from across the globe to discuss funded solar sail flight programs alongside on-going technology development and testing programs. The symposium also provided a forum for the discussion of enabling technologies, new application concepts, materials and structural concepts, space environmental effects, dynamics, navigation, control, and much more. This volume contains the unabridged symposium proceedings, in the gathered experts own words. As symposium chair, I thank our partners at Scottish Enterprise and L’Garde, Inc., the symposium’s gold sponsor, for their support in realising this symposium.

  5. Johnston Avenue Solar Project

    Energy Technology Data Exchange (ETDEWEB)

    Schrayer, David [Isles, Inc., Trenton, NJ (United States)

    2017-08-22

    DOE awarded funds to support a demonstration project to illustrate how access to solar power and green roof systems could improve building performance and long-term outcomes for the building owner and multiple nonprofit tenants housed in the building. Since being placed in service the solar PV system has saved approximately $1,000 per month in energy costs. The green roof has added to this benefit by naturally cooling the building and has helped reduce local road flooding by retaining storm water. These elements have improved the quality of life in the low-income community in which the building is located by allowing social service organizations to focus more of their resources on programs and job creation.

  6. Solar system plasma waves

    Science.gov (United States)

    Gurnett, Donald A.

    1995-01-01

    An overview is given of spacecraft observations of plasma waves in the solar system. In situ measurements of plasma phenomena have now been obtained at all of the planets except Mercury and Pluto, and in the interplanetary medium at heliocentric radial distances ranging from 0.29 to 58 AU. To illustrate the range of phenomena involved, we discuss plasma waves in three regions of physical interest: (1) planetary radiation belts, (2) planetary auroral acceleration regions and (3) the solar wind. In each region we describe examples of plasma waves that are of some importance, either due to the role they play in determining the physical properties of the plasma, or to the unique mechanism involved in their generation.

  7. Illusions in solar photosphere

    Science.gov (United States)

    Hurlburt, Neal E.; Cheung, M.

    2013-07-01

    An array of methods have been developed over the past few decades aimed at inferring the surface motion in the solar photosphere. These methods are generally based on tracking the apparent motion of features seen in the data which are, for the most part, manifestations of the thermal or magnetic structuring generated by solar magnetoconvection. Patterns formed by nonlinear magnetoconvection are known change dramatically depending on the configuration and strength of the magnetic field. These changes should be taken into account in assessing the performance of any flow-tracking method. Here we assess one method using high-fidelity numerical models of the magnetoconvection in the presence of a large-scale region of emerging flux. We compare the flow structure derived from the opflow3d method against the surface velocities contained within the simulation and investigate systematic errors introduced by local variations in field strength and inclination.

  8. Solar energy and environmental ethics

    Energy Technology Data Exchange (ETDEWEB)

    Geiger, C.J.

    1984-01-01

    Current directions in the scientific development and advocacy of solar technology emphasize its technical efficiency, its ability to function in place of conventional energy technologies, and measures of its long-run cost effectiveness. Those directions do not consider human experience or the effect of their preoccupation with technical thinking. Even environmental ethics, as it relates to solar energy, and legal aspects of the use of solar energy are biased toward finding fixed solutions to social problems. The German thinker Martin Heidegger argued that meaningful involvement in any saturation depends on one's ability to think clearly and thoroughly. Heidegger's emphasis on thinking and thoughtfulness fits best with ways of using solar energy that are appropriate to both the nature of solar energy and the lifestyles of the users. Truly appropriate use of solar energy requires what Heidegger called a composure toward solar technology, in which solar technology might change to suit new circumstances but not to the point where the user cannot control it. The horizons of solar technology itself are broadened in the context to include scientifically less-sophisticated equipment, and ways of using solar energy that reflect changes in lifestyle and greater awareness of the sun.

  9. 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...

  10. Solar Magnetic Waves and Oscillations

    Science.gov (United States)

    Erdelyi von Fay-Siebenburgen, R.

    2006-11-01

    Recent solar and space satellite missions (e.g. SOHO, Trace) and high- resolution ground-based observations (e.g. Swedish Solar Telescope, Dutch Open Telescope) have opened new avenues for 21st century plasma physics. With unprecedented details a very rich and abundant structure of the solar atmosphere is unveiled. Revolutionary observations clearly confirmed the existence of MHD waves and oscillations in a wide range of solar atmospheric magnetic structures, commonly described in the form of solar flux tubes. The objectives of this review are to give an up-to-date account of the theory of MHD waves and oscillations in solar and astrophysical magnetic wave-guides. Since magnetic structuring acts as excellent wave guides, plasma waves and oscillations are able to propagate from sub-surface solar regions through the solar atmosphere deep into the interplanetary space. Observations and theoretical modeling of waves can provide excellent diagnostic tools about the state of solar plasma. Key examples of the various types of MHD waves and oscillations will be discussed both from observational and theoretical perspectives and the concept of atmospheric (coronal) and magneto-seismology will be introduced. The lecture will also contain a few short exercises in order to highlight the important points of the applications of solar MHD wave theory.

  11. The quest for solar gravity modes: probing the solar interior

    CERN Document Server

    Mathur, S

    2009-01-01

    The solar gravity modes are the best probes to improve our knowledge on the solar interior, as they spend most of their time in the radiative zone, which represents 98% of the solar mass. Many attempts have been led to observe them using different techniques: either individually, then adding some statistical approach or more recently, globally leading to the detection of the signature of asymptotical properties of these modes. Then, several theoretical works have been done to quantify the effect of detecting g-mode on solar modeling and on the rotation profile. We will give here an update on the g-mode detection. Then, we will study an example of a theoretical work showing how their detection would improve our knowledge on the dynamics of the solar core as well as an application on the detection of the global properties to infer some physical inputs in solar models.

  12. Solar neutrinos, helioseismology and the solar internal dynamics

    CERN Document Server

    Turck-Chieze, S

    2010-01-01

    Neutrinos are fundamental particles ubiquitous in the Universe. Their properties remain elusive despite more than 50 years of intense research activity. In this review 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 to 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 waves propagating in the Sun. This review reminds the historical steps, from the pioneering Homestake detection, the GALLEX- SAGE captures of the first pp neutrinos and emphasizes the importance of the Superkamiokande and SNO detectors to demonstrate that the solar-emitted electronic neutrinos are partially...

  13. Concentrating solar thermal power.

    Science.gov (United States)

    Müller-Steinhagen, Hans

    2013-08-13

    In addition to wind and photovoltaic power, concentrating solar thermal power (CSP) will make a major contribution to electricity provision from renewable energies. Drawing on almost 30 years of operational experience in the multi-megawatt range, CSP is now a proven technology with a reliable cost and performance record. In conjunction with thermal energy storage, electricity can be provided according to demand. To date, solar thermal power plants with a total capacity of 1.3 GW are in operation worldwide, with an additional 2.3 GW under construction and 31.7 GW in advanced planning stage. Depending on the concentration factors, temperatures up to 1000°C can be reached to produce saturated or superheated steam for steam turbine cycles or compressed hot gas for gas turbine cycles. The heat rejected from these thermodynamic cycles can be used for sea water desalination, process heat and centralized provision of chilled water. While electricity generation from CSP plants is still more expensive than from wind turbines or photovoltaic panels, its independence from fluctuations and daily variation of wind speed and solar radiation provides it with a higher value. To become competitive with mid-load electricity from conventional power plants within the next 10-15 years, mass production of components, increased plant size and planning/operating experience will be accompanied by technological innovations. On 30 October 2009, a number of major industrial companies joined forces to establish the so-called DESERTEC Industry Initiative, which aims at providing by 2050 15 per cent of European electricity from renewable energy sources in North Africa, while at the same time securing energy, water, income and employment for this region. Solar thermal power plants are in the heart of this concept.

  14. Solar-Terrestrial Interactions

    Science.gov (United States)

    2008-01-01

    observed. We worked out a polar theory that incorporates molecular ions and shows that they are expected to be associated with large outflow speeds...because of the change in the mean molecular degrees of freedom of the plasma. We calculated vertical cutoff rigidities for spacecraft altitudes and...E. Lamanna, Societa Italiana di Fisica , Bologna, Italy, 1997.) Shea, M.A., and D.F. Smart, Overview of the Effects of Solar Terrestrial Phenomena

  15. Passive solar homes

    Energy Technology Data Exchange (ETDEWEB)

    Brown, T.

    1981-01-01

    After a brief description of the basic principles of passive solar heating, the use of thermal mass in a passive house is discussed, including the Trombe wall, water wall, roof ponds, and the attached greenhouse. Direct gain through skylights and clerestories is also discussed. The selection of a lot and the orientation of the house on the lot are covered. The example of a passive house outside Santa Fe, New Mexico is cited for its performance. (LEW)

  16. 2015 Solar Decathalon

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, George [Alfred Univ. and Alfred State College, NY (United States)

    2015-11-20

    A final report is submitted for the results of Team Alfred’s participation in the 2015 Solar Decathlon held in October of that year in Irvine California. More than 30 people traveled the distance from Alfred NY to Irvine to participate in the assembly and contest of the ALF house. The results of what the team learned, the experience we had, and what we would have done differently are included in this report.

  17. Cajal on solar eclipse.

    Science.gov (United States)

    Triarhou, Lazaros C; del Cerro, Manuel

    2008-01-01

    An impression that sculpted a lasting memory on the mind of the great neuroanatomist Santiago Ramón y Cajal, an 8-year-old boy at the time, was the total solar eclipse of 18 July 1860. This short article provides a translation of the relevant passage, found in a 1933 Buenos Aires schoolbook, and places the celestial event at the crossroads of neuroscience, astronomy and literature.

  18. Solar Technology Center

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, Bob

    2011-04-27

    The Department of Energy, Golden Field Office, awarded a grant to the UNLV Research Foundation (UNLVRF) on August 1, 2005 to develop a solar and renewable energy information center. The Solar Technology Center (STC) is to be developed in two phases, with Phase I consisting of all activities necessary to determine feasibility of the project, including design and engineering, identification of land access issues and permitting necessary to determine project viability without permanently disturbing the project site, and completion of a National Environmental Policy Act (NEPA) Environmental Assessment. Phase II is the installation of infrastructure and related structures, which leads to commencement of operations of the STC. The STC is located in the Boulder City designated 3,000-acre Eldorado Valley Energy Zone, approximately 15 miles southwest of downtown Boulder City and fronting on Eldorado Valley Drive. The 33-acre vacant parcel has been leased to the Nevada Test Site Development Corporation (NTSDC) by Boulder City to accommodate a planned facility that will be synergistic with present and planned energy projects in the Zone. The parcel will be developed by the UNLVRF. The NTSDC is the economic development arm of the UNLVRF. UNLVRF will be the entity responsible for overseeing the lease and the development project to assure compliance with the lease stipulations established by Boulder City. The STC will be operated and maintained by University of Nevada, Las Vegas (UNLV) and its Center for Energy Research (UNLV-CER). Land parcels in the Eldorado Valley Energy Zone near the 33-acre lease are committed to the construction and operation of an electrical grid connected solar energy production facility. Other projects supporting renewable and solar technologies have been developed within the energy zone, with several more developments in the horizon.

  19. Solar Structures Program

    Science.gov (United States)

    2015-03-27

    University of New Mexico (UNM) to develop a series of solar powered balloon and glider systems to allow for testing of electronics in high altitude and...motherboard operates on a state-of-the- art Texas Instrument’s processor. The control system was written in the object oriented programming language...Responsive Space SORTIE Scintillation Observations and Response of The Ionosphere to Electrodynamics UNM University of New Mexico VDC Volts Direct

  20. Automation of solar plants

    Energy Technology Data Exchange (ETDEWEB)

    Yebra, L.J.; Romero, M.; Martinez, D.; Valverde, A. [CIEMAT - Plataforma Solar de Almeria, Tabernas (Spain); Berenguel, M. [Almeria Univ. (Spain). Departamento de Lenguajes y Computacion

    2004-07-01

    This work overviews some of the main activities and research lines that are being carried out within the scope of the specific collaboration agreement between the Plataforma Solar de Almeria-CIEMAT (PSA-CIEMAT) and the Automatic Control, Electronics and Robotics research group of the Universidad de Almeria (TEP197) titled ''Development of control systems and tools for thermosolar plants'' and the projects financed by the MCYT DPI2001-2380-C02-02 and DPI2002-04375-C03. The research is directed by the need of improving the efficiency of the process through which the energy provided by the sun is totally or partially used as energy source, as far as diminishing the costs associated to the operation and maintenance of the installations that use this energy source. The final objective is to develop different automatic control systems and techniques aimed at improving the competitiveness of solar plants. The paper summarizes different objectives and automatic control approaches that are being implemented in different facilities at the PSA-CIEMAT: central receiver systems and solar furnace. For each one of these facilities, a systematic procedure is being followed, composed of several steps: (i) development of dynamic models using the newest modeling technologies (both for simulation and control purposes), (ii) development of fully automated data acquisition and control systems including software tools facilitating the analysis of data and the application of knowledge to the controlled plants and (iii) synthesis of advanced controllers using techniques successfully used in the process industry and development of new and optimized control algorithms for solar plants. These aspects are summarized in this work. (orig.)

  1. Autonomous solar refrigerator

    Energy Technology Data Exchange (ETDEWEB)

    Bougard, J.; Vokaert, D. (Faculte Polytechnique de Mons, Universite Libre de Bruxelles (Belgium))

    1982-11-01

    A compression refrigerator, fed by a flat solar pannel and composed of two thermal machines, working on a Rankine-Hirn cycle, is described. Mechanical energy is transferred by a double effect free-piston which is at the same time engine, pump, compressor and electric generator for auxiliaries. Freon R12 or R114 is used as the working fluid. Performances of a prototype are given. Investment for a classical unit, fed by a photovoltaic pannel would be more than twice.

  2. Localized solar collectors

    Energy Technology Data Exchange (ETDEWEB)

    Ghasemi, Hadi; Marconnet, Amy Marie; Chen, Gang; Ni, George Wei

    2016-10-04

    A localized heating structure, and method of forming same, for use in solar systems includes a thermally insulating layer having interconnected pores, a density of less than about 3000 kg/m.sup.3, and a hydrophilic surface, and an expanded carbon structure adjacent to the thermally insulating layer. The expanded carbon structure has a porosity of greater than about 80% and a hydrophilic surface.

  3. Thin, Lightweight Solar Cell

    Science.gov (United States)

    Brandhorst, Henry W., Jr.; Weinberg, Irving

    1991-01-01

    Improved design for thin, lightweight solar photovoltaic cells with front contacts reduces degradation of electrical output under exposure to energetic charged particles (protons and electrons). Increases ability of cells to maintain structural integrity under exposure to ultraviolet radiation by eliminating ultraviolet-degradable adhesives used to retain cover glasses. Interdigitated front contacts and front junctions formed on semiconductor substrate. Mating contacts formed on back surface of cover glass. Cover glass and substrate electrostatically bonded together.

  4. Commercializing solar architecture

    Energy Technology Data Exchange (ETDEWEB)

    Franta, G.

    1979-03-01

    The seminar discussions on attitudinal, technical, and institutional issues and the suggestions related to information development, acquisition, and dissemination; education and training; demonstrations and design competitions; and other actions are documented. Information on SERI's overall mission and a paper titled, The Architectural Role of SERI, and a matrix of barriers and actions from this assessment, related to the commercialization profile for passive solar heating, are attached as appendices.

  5. Fabricating sub-collimating grids for an x-ray solar imaging spectrometer using LIGA techniques

    Energy Technology Data Exchange (ETDEWEB)

    Brennen, R.A.; Hecht, M.H.; Wiberg, D.V. [Jet Propulsion Lab., Pasadena, CA (United States)] [and others

    1997-04-01

    The HESSI mission proposes to perform high resolution imaging and spectroscopy observations in the soft X-ray, hard X-ray, and gamma-ray regimes, with finer angular resolution (nearly 2 arcseconds) and finer energy resolution (approximately 1 keV) than has been previously possible. This combination of imaging and spectroscopy is achieved with a set of Rotating Modulation Collimators placed in front of an array of cooled germanium and silicon detectors. A set of 12 bi-grid collimators, each of which consists of a pair of identically pitched, widely-separated grids, is used to provide the imaging. Each grid consists of a planar array of equally-spaced, parallel, X-ray opaque slats separated by X-ray transparent slits. If the slits of each grid are parallel to each other and the pitch is identical for the two grids, then the transmission through the grid pair depends on the direction of incidence of the incoming X-rays. For slits and slats of equal width, the transmission varies between zero and 50% depending on whether the shadows of the slats in the top grid fall on the slits or slats of the lower grid. A complete transmission cycle from zero to 50% and back to zero corresponds to a change in source direction that is given by p/L, where L is the separation between the grids. The authors describe a deep etch lithography technique developed to fabricate the grids which have pitches below 100 {micro}m. They use a free standing sheet of PMMA as a base for the process, and use the ALS facility to perform the exposures of the PMMA.

  6. EDITORIAL: Nanostructured solar cells Nanostructured solar cells

    Science.gov (United States)

    Greenham, Neil C.; Grätzel, Michael

    2008-10-01

    Conversion into electrical power of even a small fraction of the solar radiation incident on the Earth's surface has the potential to satisfy the world's energy demands without generating CO2 emissions. Current photovoltaic technology is not yet fulfilling this promise, largely due to the high cost of the electricity produced. Although the challenges of storage and distribution should not be underestimated, a major bottleneck lies in the photovoltaic devices themselves. Improving efficiency is part of the solution, but diminishing returns in that area mean that reducing the manufacturing cost is absolutely vital, whilst still retaining good efficiencies and device lifetimes. Solution-processible materials, e.g. organic molecules, conjugated polymers and semiconductor nanoparticles, offer new routes to the low-cost production of solar cells. The challenge here is that absorbing light in an organic material produces a coulombically bound exciton that requires dissociation at a donor-acceptor heterojunction. A thickness of at least 100 nm is required to absorb the incident light, but excitons only diffuse a few nanometres before decaying. The problem is therefore intrinsically at the nano-scale: we need composite devices with a large area of internal donor-acceptor interface, but where each carrier has a pathway to the respective electrode. Dye-sensitized and bulk heterojunction cells have nanostructures which approach this challenge in different ways, and leading research in this area is described in many of the articles in this special issue. This issue is not restricted to organic or dye-sensitized photovoltaics, since nanotechnology can also play an important role in devices based on more conventional inorganic materials. In these materials, the electronic properties can be controlled, tuned and in some cases completely changed by nanoscale confinement. Also, the techniques of nanoscience are the natural ones for investigating the localized states, particularly at

  7. DUALPURPOSE SOLAR OVEN

    Directory of Open Access Journals (Sweden)

    S. H. Sengar

    2010-10-01

    Full Text Available Dual purpose solar oven (DPSO was designed and constructed. It observed that by using the new design of solar oven, both function of cooking and drying were possible for meeting the requirement of a family. The maximum stagnation temperature of 119°C and water temperature of 93.25°C were obtained in winter in DPSO while using as cooker. The calculated values of figure of merit F in DPSO was 0.119 and the time duration 1 for raising water temperature from 60 C to 90°C in hot box was 120 min. Cooking trials have also been conducted 0.5 kg of rice in 1 kg of water and 0.250 Kg of green gram split washed in one and half hrs in winter while it took about one hour in summer. The maximum temperature of 58 °C was recorded at 14:00 hrs of the day at level of tray no.2 when used as dryer. The time required to dry maize on different trays upto average moisture content 7.13 %( w.w. for winter and 5.43 %( w.w. for summer (w.w.was 420 minute and 360 minute respectively. The total cost of solar oven was worked out to be Rs(.2,715. Its pay back period varied between 1.3 to 1.86 years depending upon fuel it replaced.

  8. Solar battery energizer

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, M. E.

    1985-09-03

    A battery energizer for button batteries, such as zinc-silver oxide or zinc-mercuric oxide batteries, that are normally considered unchargeable, provides for energizing of the batteries in a safe and simple manner. A solar cell having a maximum current output (e.g., 20 milliamps) is operatively connected to terminals for releasably receiving a button battery. A light emitting diode, or like indicator, provides an indication of when the battery is fully energized, and additionally assists in preventing overenergization of the battery. The solar cell, terminals, LED, and the like can be mounted on a nonconductive material mounting plate which is mounted by a suction cup and hook to a window, adjacent a light bulb, or the like. A battery charger for conventional dry cell rechargeable batteries (such as nickel-cadmium batteries) utilizes the solar cells, and LED, and a zener diode connected in parallel with terminals. An adaptor may be provided with the terminal for adapting them for use with any conventional size dry cell battery, and a simple dummy battery may be utilized so that less than the full complement of batteries may be charged utilizing the charger.

  9. Helioseismology with Solar Orbiter

    CERN Document Server

    Löptien, Björn; Gizon, Laurent; Schou, Jesper; Appourchaux, Thierry; Rodríguez, Julián Blanco; Cally, Paul S; Dominguez-Tagle, Carlos; Gandorfer, Achim; Hill, Frank; Hirzberger, Johann; Scherrer, Philip H; Solanki, Sami K

    2014-01-01

    The Solar Orbiter mission, to be launched in July 2017, will carry a suite of remote sensing and in-situ instruments, including the Polarimetric and Helioseismic Imager (PHI). PHI will deliver high-cadence images of the Sun in intensity and Doppler velocity suitable for carrying out novel helioseismic studies. The orbit of the Solar Orbiter spacecraft will reach a solar latitude of up to 21 deg (up to 34 deg by the end of the extended mission) and thus will enable the first local helioseismology studies of the polar regions. Here we consider an array of science objectives to be addressed by helioseismology within the baseline telemetry allocation (51 Gbit per orbit, current baseline) and within the science observing windows (baseline 3 x 10 days per orbit). A particularly important objective is the measurement of large-scale flows at high latitudes (rotation and meridional flow), which are largely unknown but play an important role in flux transport dynamos. The full range of Earth-Sun-spacecraft angles provi...

  10. Solar System Voyage

    Science.gov (United States)

    Brunier, Serge

    2002-11-01

    In the last few decades, the exploration of our solar system has revealed fascinating details about the worlds that lie beyond our Earth. This lavishly illustrated book invites the reader on a journey through the solar system. After locating our planetary system in the Universe, Brunier describes the Sun and its planets, the large satellites, asteroids, and comets. Photographs and information taken from the latest space missions allow readers to experience spectacular scenes: the lunar plains scarred by asteroid impacts, the frozen deserts of Mars and Europa, the continuously erupting volcanoes of Io and the giant geysers of Triton, the rings of Saturn and the clouds of Venus and Titan, and the powerful crash of the comet Shoemaker-Levy into Jupiter. Inspired by the extraordinary photographs and incisive text, readers of Solar System Voyage will gain a greater appreciation of the hospitable planet we call home. Serge Brunier is chief editor of the journal Ciel et Espace, a photojournalist, and the author of many nonfiction books aimed at both specialists and the general public. His previous books include Space Odyssey (Cambridge, 2002), Glorious Eclipses with Jean-Pierre Luminet (Cambridge, 2000), and Majestic Universe (Cambridge, 1999).

  11. Corona and solar wind

    Science.gov (United States)

    Withbroe, G. L.

    1986-04-01

    The Pinhole/Occulter Facility is a powerful tool for studying the physics of the extended corona and origins of the solar wind. Spectroscopic data acquired by the P/OF coronal instruments can greatly expand empirical information about temperatures, densities, flow velocities, magnetic fields, and chemical abundances in the corona out to r or approx. 10 solar radii. Such information is needed to provide tight empirical constraints on critical physical processes involved in the transport and dissipation of energy and momentum, the heating and acceleration of plasma, and the acceleration of energetic particles. Because of its high sensitivity, high spatial and temporal resolutions, and powerful capabilities for plasma diagnostics, P/OF can significantly increase our empirical knowledge about coronal streamers and transients and thereby advance the understanding of the physics of these phenomena. P/OF observations can be used to establish the role in solar wind generation, if any, of small-scale dynamical phenomena, such as spicules, macrospicules and coronal bullets, and the role of the fine-scale structures, such as polar plumes. Finally, simultaneous measurements by the P/OF coronal and hard X-ray instruments can provide critical empirical information concerning nonthermal energy releases and acceleration of energetic particles in the corona.

  12. Solar extreme events

    CERN Document Server

    Hudson, Hugh S

    2015-01-01

    Solar flares and CMEs have a broad range of magnitudes. This review discusses the possibility of "extreme events," defined as those with magnitudes greater than have been seen in the existing historical record. For most quantitative measures, this direct information does not extend more than a century and a half into the recent past. The magnitude distributions (occurrence frequencies) of solar events (flares/CMEs) typically decrease with the parameter measured or inferred (peak flux, mass, energy etc. Flare radiation fluxes tend to follow a power law slightly flatter than $S^{-2}$, where S represents a peak flux; solar particle events (SPEs) follow a still flatter power law up to a limiting magnitude, and then appear to roll over to a steeper distribution, which may take an exponential form or follow a broken power law. This inference comes from the terrestrial $^{14}$C record and from the depth dependence of various radioisotope proxies in the lunar regolith and in meteorites. Recently major new observation...

  13. Solar drying and agribusiness

    Directory of Open Access Journals (Sweden)

    Sebastiana del Monserrate Ruiz Cedeño

    2016-07-01

    Full Text Available Agribusinesses are the livelihoods of rural populations, but when production increase, many products are damaged and lose their commercial value due to lack of conservation treatments at a local level. Agricultural production represents the foundation of economic development of the province of Manabi. A significant level of agricultural products is lost due to lack of conservation technologies. Solar drying is a way of conserving by dehydration of some products such as: vegetables, fruits, aromatic and medicinal plants. This can be achieved by a process of proper conservation that is conducive to reduce losses using technologies easy to build, as are the different types of solar dryers which are already used in different parts of the South American region. This article proposes to introduce solar-drying technology in agricultural areas of the province of Manabi. And thereby achieve the regaining of different products that today are lost, incorporating new and attractive, marketable lines based on agricultural products naturally dehydrated with a high nutritionalvalue, capable of contributing to human health not only in the province but also in the country.

  14. KamLAND, solar antineutrinos and the solar magnetic field

    CERN Document Server

    Chauhan, B C; Torrente-Lujan, E; Chauhan, Bhag C.; Pulido, Joao

    2003-01-01

    In this work the possibility of detecting solar electron antineutrinos produced by a solar core magnetic field from the KamLAND recent observations is investigated. We find a scaling of the antineutrino probability with respect to the magnetic field profile in the sense that the same probability function can be reproduced by any profile with a suitable peak field value. In this way the solar electron antineutrino spectrum can be unambiguosly predicted. We use this scaling and the negative results indicated by the KamLAND experiment to obtain upper bounds on the solar electron antineutrino flux. We get $\\phi_{\\bar\

  15. 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.; Lowther, S. E.; Lillehei, P. T.; Bryant, R. G.

    2012-01-01

    Tailoring the solar absorptivity (alpha(sub s)) and thermal emissivity (epsilon(sub T)) of materials constitutes an innovative approach to solar energy control and energy conversion. Numerous ceramic and metallic materials are currently available for solar absorbance/thermal emittance control. However, conventional metal oxides and dielectric/metal/dielectric multi-coatings have limited utility due to residual shear stresses resulting from the different coefficient of thermal expansion of the layered materials. This research presents an alternate approach based on nanoparticle-filled polymers to afford mechanically durable solar-absorptive and thermally-emissive polymer nanocomposites. The alpha(sub s) and epsilon(sub T) were measured with various nano inclusions, such as carbon nanophase particles (CNPs), at different concentrations. Research has shown that adding only 5 wt% CNPs increased the alpha(sub s) and epsilon(sub T) by a factor of about 47 and 2, respectively, compared to the pristine polymer. The effect of solar irradiation control of the nanocomposite on solar energy conversion was studied. The solar irradiation control coatings increased the power generation of solar thermoelectric cells by more than 380% compared to that of a control power cell without solar irradiation control coatings.

  16. Developing The Solar Tracking System for Trough Solar Concentrator

    Directory of Open Access Journals (Sweden)

    Nguyen Huy Bich

    2016-01-01

    Full Text Available The efficiency of the trough solar concentrator strongly depends on the position of its absorber surface with the sun.  Controlling the solar radiation concentrated collectors automatically tracking with the sun plays as the key factor to enhance the energy absorption. An automatic controlling device that can rotating the parabolic trough solar concentrator to the sun is calculated, designed, manufactured, and testing successfully. The experimental results show that the device tracks the sun during the day very well. The sensor has adjusted position of collector good when the intensity of solar radiation changes due to weather.

  17. 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.

  18. The Solar Tracking System by Using Digital Solar Position Sensor

    Directory of Open Access Journals (Sweden)

    Singthong Pattanasethanon

    2010-01-01

    Full Text Available Problem statement: An optimal control on two axes and design for solar tracker which called altitude and azimuth is challenge. Approach: The phototransistor with the shade that blocks the screen was employed as a detector of solar beam radiation. The height of the screen determined the sensitivity operation or period of tracking in this solar tracker. The phototransistor is particularly designed to detect solar bean radiation thoroughly through the two axes with the operating time. The mechanism of this solar tracker is that it has a capacity of solar tracking in every 10 min, approximately, which respond in terms of time at about 37° sec-1 with and operating point at 0.3 sec. Results: Our solar tracker obtained an average deviation at about 2.5deg;h-1. In weak sunlight however, the value varies and fluctuates rapidly depending on sky condition. Conclusion: The accuracy of solar position tracking function satisfied our goal as well. There is only average of 2.5deg; error shown. The experiment also shows that the error rate diminishes as the solar radiance expand. However, we hope to develop this device to be more exact in the position.

  19. solar magnetic fiber and space solar telescope in engineering model

    Science.gov (United States)

    Ai, G.

    The solar magnetic fiber and the magnetic element are the most important factor in the solar activity and solar atmosphere. Because the space resolution of measurement of solar magnetic field is much lower than that of the size of the nature solar magnetic fiber and element from the earth atmospheric turbulence. The estimate of the magnetic element nature from various indirect researches shows great difference with several orders. The research results about magnetic elements have been reviewed in the paper.Because the size of the magnetic element has been estimated for 0.1T-0.2T, the space solar magnetic field telescope with big diameter is the most basic choice. For the exploration of solar magnetic fiber and element, a Space Solar Telescope is under development in the phase C and D, there are five payloads which are: 1) MOT, 1 diameter telescope with 8 channels real time 2-D spectrograph and 8 sets CCD with 2K`2K; 2) EUV, 4 tubes of soft X-ray Telescope with 0.252 space resolution; 3) WBS, the wide Band Spectrometer with 256 channel from soft X-ray to Gamma-ray. 4) HAT, Ha and white light telescope; 5) SIRA, Solar and interplanetary Radio Spectrometer, with 100 KHZ-60 MHZ. The assembly and test will be introduced.

  20. Fundamentals of Solar Heating. Correspondence Course.

    Science.gov (United States)

    Sheet Metal and Air Conditioning Contractors National Association, Vienna, VA.

    This course is designed for the use of employees of the air conditioning industry, and offers supervised correspondence instruction about solar technology. The following aspects of applied solar technology are covered: solar heating and cooling, solar radiation, solar collectors, heat storage control devices and specialty items, sizing solar…

  1. 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

  2. Dust Removal from Solar Cells

    Science.gov (United States)

    Ashpis, David E. (Inventor)

    2015-01-01

    A solar panel cleaning device includes a solar panel having a plurality of photovoltaic cells arranged in rows and embedded in the solar panel with space between the rows. A transparent dielectric overlay is affixed to the solar panel. A plurality of electrode pairs each of which includes an upper and a lower electrode are arranged on opposite sides of the transparent dielectric and are affixed thereto. The electrodes may be transparent electrodes which may be arranged without concern for blocking sunlight to the solar panel. The solar panel may be a dielectric and its dielectric properties may be continuously and spatially variable. Alternatively the dielectric used may have dielectric segments which produce different electrical field and which affects the wind "generated."

  3. Solar index generation and delivery

    Energy Technology Data Exchange (ETDEWEB)

    Lantz, L.J.

    1980-01-01

    The Solar Index, or, more completely defined as the Service Hot Water Solar Index, was conceptualized during the spring of 1978. The purpose was to enhance public awareness to solar energy usability. Basically, the Solar Index represents the percentage of energy that solar would provide in order to heat an 80 gallon service hot water load for a given location and day. The Index is computed by utilizing SOLCOST, a computer program, which also has applications to space heating, cooling, and heat pump systems and which supplies economic analyses for such solar energy systems. The Index is generated for approximately 68 geographic locations in the country on a daily basis. The definition of the Index, how the project came to be, what it is at the present time and a plan for the future are described. Also presented are the models used for the generation of the Index, a discussion of the primary tool of implementation (the SOLCOST program) and future efforts.

  4. Solar cell materials developing technologies

    CERN Document Server

    Conibeer, Gavin J

    2014-01-01

    This book presents a comparison of solar cell materials, including both new materials based on organics, nanostructures and novel inorganics and developments in more traditional photovoltaic materials. It surveys the materials and materials trends in the field including third generation solar cells (multiple energy level cells, thermal approaches and the modification of the solar spectrum) with an eye firmly on low costs, energy efficiency and the use of abundant non-toxic materials.

  5. Light shield for solar concentrators

    Energy Technology Data Exchange (ETDEWEB)

    Plesniak, Adam P.; Martins, Guy L.

    2014-08-26

    A solar receiver unit including a housing defining a recess, a cell assembly received in the recess, the cell assembly including a solar cell, and a light shield received in the recess and including a body and at least two tabs, the body defining a window therein, the tabs extending outward from the body and being engaged with the recess, wherein the window is aligned with the solar cell.

  6. Large-scale solar heat

    Energy Technology Data Exchange (ETDEWEB)

    Tolonen, J.; Konttinen, P.; Lund, P. [Helsinki Univ. of Technology, Otaniemi (Finland). Dept. of Engineering Physics and Mathematics

    1998-12-31

    In this project a large domestic solar heating system was built and a solar district heating system was modelled and simulated. Objectives were to improve the performance and reduce costs of a large-scale solar heating system. As a result of the project the benefit/cost ratio can be increased by 40 % through dimensioning and optimising the system at the designing stage. (orig.)

  7. Progress in Space Solar Telescope

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In this paper we will summarize the progress in the development of the Chinese Space Solar Telescope (SST) during the past few years. The main scientific objective of SST is to observe the fundamental structure of solar magnetic field with its 1-m optical telescope. The success of 1-m Swedish Solar Telescope and Hinode underscores the importance of this 1-m space telescope. In addition, some key technical problems have been solved.

  8. Solar Eclipses Observed from Antarctica

    OpenAIRE

    2013-01-01

    Aspects of the solar corona are still best observed during totality of solar eclipses, and other high-resolution observations of coronal active regions can be observed with radio telescopes by differentiation of occultation observations, as we did with the Jansky Very Large Array for the annular solar eclipse of 2012 May 20 in the US. Totality crossing Antarctica included the eclipse of 2003 November 23, and will next occur on 2021 December 4; annularity crossing Antarctica included the eclip...

  9. Solar influence on Earth's climate

    DEFF Research Database (Denmark)

    Marsh, N.; Svensmark, Henrik

    2003-01-01

    An increasing number of studies indicate that variations in solar activity have had a significant influence on Earth's climate. However, the mechanisms responsible for a solar influence are still not known. One possibility is that atmospheric transparency is influenced by changing cloud properties...... and thereby influence the radiative properties of clouds. If the GCR-Cloud link is confirmed variations in galactic cosmic ray flux, caused by changes in solar activity and the space environment, could influence Earth's radiation budget....

  10. 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…

  11. Space Solar Cell Characterization Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Measures, characterizes, and analyzes photovoltaic materials and devices. The primary focus is the measurement and characterization of solar cell response...

  12. Passive-solar construction handbook

    Energy Technology Data Exchange (ETDEWEB)

    Levy, E.; Evans, D.; Gardstein, C.

    1981-02-01

    Many of the basic elements of passive solar design are reviewed. Passive solar construction is covered according to system type, each system type discussion including a general discussion of the important design and construction issues which apply to the particular system and case studies illustrating designed and built examples of the system type. The three basic types of passive solar systems discussed are direct gain, thermal storage wall, and attached sunspace. Thermal performance and construction information is presented for typical materials used in passive solar collector components, storage components, and control components. Appended are an overview of analysis methods and a technique for estimating performance. (LEW)

  13. Comprehensive Solar Sail Simulation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Solar sails as a propulsive device have several potential applications: providing access to previously inaccessible orbits, longer mission times, and increased...

  14. 2005 Solar Decathlon (Competition Program)

    Energy Technology Data Exchange (ETDEWEB)

    2005-10-01

    The 2005 Solar Decathlon Competition Program is distributed to Solar Decathlon visitors, media, sponsors, and the student competitors. It contains basic facts about the Solar Decathlon: what, where, when, who, and how. It is a guide for visitors to the events and workshops. It describes the 10 contests and the technologies used in the houses. It celebrates the accomplishments of the competitors and provides an opportunity for the major sponsors to describe their roles and relay their commitment to the ideals of the Solar Decathlon.

  15. Solar information user priority study

    Energy Technology Data Exchange (ETDEWEB)

    Belew, W.W.; Wood, B.L.

    1980-05-01

    This report identifies for each solar technology those members or potential members of the solar community who, either currently or in the future, will require solar information. In addition, it rates each user's relative need for information within the next three years. This information will be used as input for subsequent studies that will identify specific user needs information. These studies, in turn, will be the basis for information product and data base development for the Solar Energy Information Data Bank (SEIDB). In addition, they will be input for the Technical Information Dissemination (TID) Program.

  16. Support for solar energy collectors

    Science.gov (United States)

    Cole, Corey; Ardell-Smith, Zachary; Ciasulli, John; Jensen, Soren

    2016-11-01

    A solar energy collection system can include support devices configured to accommodate misalignment of components during assembly. For example, the system can include piles fixed to the earth and an adjustable bearing assembly at the upper end of the pile. The adjustable bearing assembly can include at least one of a vertical adjustment device, a lateral adjustment device and an angular adjustment device. The solar energy collection system can also include a plurality of solar energy collection device pre-wired together and mounted to a support member so as to form modular units. The system can also include enhanced supports for wire trays extending between rows of solar energy collection devices.

  17. Solar air systems - built examples

    Energy Technology Data Exchange (ETDEWEB)

    Hastings, S.R. [ed.] [Solararchitektur, ETH-Hoenggerberg, Zurich (Switzerland)

    1999-07-01

    Active solar systems for air heating are a straightforward yet efficient way of using solar energy to heat spaces, ventilation air and even domestic hot water. They offer important advantages over solar water systems, improved comfort and fuller use of solar gains compared with many passive solar systems and are a natural fit with mechanically ventilated buildings. Solar air systems become more economical when they serve multiple functions such as providing a sound barrier, a weatherskin, sunshading, inducing cooling and even electricity supply (hybrid PV/air). Thirty-five different buildings with successfully installed exemplary solar air systems in climates ranging from Canada and Norway to Italy are described and documented. The building types cover single family houses, apartment buildings, schools, sports halls, and industrial commercial buildings with six different configurations of solar air systems used. Each building is described over several pages, with plans, performance details and illustrations provided. An accompanying product catalogue identifies suppliers of the necessary equipment and offers advice on product selection. As well as giving architects and designers invaluable advice based on the experience from these projects, this book also illustrates clearly the wide range of applications and the many benefits of solar air systems. (author)

  18. Solar Fuels: Vision and Concepts

    OpenAIRE

    Styring, Stenbjörn

    2012-01-01

    The world needs new, environmentally friendly and renewable fuels to allow an exchange from fossil fuels. The fuel must be made from cheap and ‘endless’ resources that are available everywhere. The new research area on solar fuels, which are made from solar energy and water, aims to meet this demand. The paper discusses why we need a solar fuel and why electricity is not enough; it proposes solar energy as the major renewable energy source to feed from. The present research strategies, involv...

  19. Solar Cycle Predictions (Invited Review)

    Science.gov (United States)

    Pesnell, W. Dean

    2012-11-01

    Solar cycle predictions are needed to plan long-term space missions, just as weather predictions are needed to plan the launch. Fleets of satellites circle the Earth collecting many types of science data, protecting astronauts, and relaying information. All of these satellites are sensitive at some level to solar cycle effects. Predictions of drag on low-Earth orbit spacecraft are one of the most important. Launching a satellite with less propellant can mean a higher orbit, but unanticipated solar activity and increased drag can make that a Pyrrhic victory as the reduced propellant load is consumed more rapidly. Energetic events at the Sun can produce crippling radiation storms that endanger all assets in space. Solar cycle predictions also anticipate the shortwave emissions that cause degradation of solar panels. Testing solar dynamo theories by quantitative predictions of what will happen in 5 - 20 years is the next arena for solar cycle predictions. A summary and analysis of 75 predictions of the amplitude of the upcoming Solar Cycle 24 is presented. The current state of solar cycle predictions and some anticipations of how those predictions could be made more accurate in the future are discussed.

  20. Solar astrophysics. 3. rev. ed.

    Energy Technology Data Exchange (ETDEWEB)

    Foukal, Peter V. [CRI, Nahant, MA (United States)

    2013-06-01

    This third, revised edition describes our current understanding of the sun - from its deepest interior, via the layers of the directly observable atmosphere to the solar wind, right up to its farthest extension into interstellar space. It includes a comprehensive account of the history of solar astrophysics, and the evolution of solar instruments. This account now includes the most up- to-date implementation of modern solar instruments in facilities on the ground and in space. The revised book now also provides an overview of recent results on ''space weather'' and on sun-climate relations, both of which are fields of increasing societal importance.

  1. Dye Sensitized Solar Cell, DSSC

    Directory of Open Access Journals (Sweden)

    Pongsatorn Amornpitoksuk

    2003-07-01

    Full Text Available A dye sensitized solar cell is a new type of solar cell. The operating system of this solar cell type is similar to plant’s photosynthesis process. The sensitizer is available for absorption light and transfer electrons to nanocrystalline metal oxide semiconductor. The ruthenium(II complexes with polypyridyl ligands are usually used as the sensitizers in solar cell. At the present time, the complex of [Ru(2,2',2'’-(COOH3- terpy(NCS3] is the most efficient sensitizer. The total photon to current conversion efficiency was approximately 10% at AM = 1.5.

  2. Nanostructuring of Solar Cell Surfaces

    DEFF Research Database (Denmark)

    Davidsen, Rasmus Schmidt; Schmidt, Michael Stenbæk

    Solar energy is by far the most abundant renewable energy source available, but the levelized cost of solar energy is still not competitive with that of fossil fuels. Therefore there is a need to improve the power conversion effciency of solar cells without adding to the production cost. The main...... objective of this PhD thesis is to develop nanostructured silicon (Si) solar cells with higher power conversion efficiency using only scalable and cost-efficient production methods. The nanostructures, known as 'black silicon', are fabricated by single-step, maskless reactive ion etching and used as front...

  3. On the Cause of Solar Differential Rotations in the Solar Interior and Near the Solar Surface

    Science.gov (United States)

    Lyu, L.

    2012-12-01

    A theoretical model is proposed to explain the cause of solar differential rotations observed in the solar interior and near the solar surface. We propose that the latitudinal differential rotation in the solar convection zone is a manifestation of an easterly wind in the mid latitude. The speed of the easterly wind is controlled by the magnitude of the poleward temperature gradient in the lower part of the solar convection zone. The poleward temperature gradient depends on the orientation and strength of the magnetic fields at different latitudes in the solar convection zone. The north-south asymmetry in the wind speed can lead to north-south asymmetry in the evolution of the solar cycle. The easterly wind is known to be unstable for a west-to-east rotating star or planet. Based on the observed differential rotations in the solar convection zone, we can estimate the easterly wind speed at about 60-degree latitude and determine the azimuthal wave number of the unstable wave modes along the zonal flow. The lowest azimuthal wave number is about m=7~8. This result is consistent with the average width of the elephant-trunk coronal hole shown in the solar X-ray images. The nonlinear evolution of the unstable easterly wind can lead to transpolar migration of coronal holes and can change the poloidal magnetic field in a very efficient way. In the study of radial differential rotation near the solar surface, we propose that the radial differential rotation depends on the radial temperature gradient. The radial temperature gradient depends on the magnetic field structure above the solar surface. The non-uniform magnetic field distribution above the solar surface can lead to non-uniform radial convections and formation of magnetic flux rope at different spatial scales. The possible cause of continuous formation and eruption of prominences near an active region will also be discussed.

  4. Solar energy perspectives for public power

    Energy Technology Data Exchange (ETDEWEB)

    Woodley, N. H.

    1979-06-01

    Perspectives on the utilization of solar energy for electricity production and thermal energy utilization by the public are briefly discussed. Wind energy conversion, biomass conversion, solar thermal, OTEC, photovoltaics, and solar heating and cooling are discussed. (WHK)

  5. Boston solar retrofits: studies of solar access and economics

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, M.

    1980-11-01

    Studies of solar access and solar retrofit economics are described for residential applications in the City of Boston. The study of solar access was based upon a random sample of 94 buildings; the sample was stratified to ensure a broad geographic representation from the city's various sections. Using available data on the heights and orientations of the sampled structures and surrounding buildings, each building's hourly access to sunlight was computed separately for the roof and south facing walls. These data were then aggregated by broad structural classifications in order to provide general measures of solar access. The second study was a comparative analysis of the economics of several solar heating and hot water systems. An active hot water system, installed using pre-assembled, commercially purchased equipment, was selected as a reference technology. A variety of measures of economic performance were computed for this system, with and without existing tax credits and under various financing arrangements. Next, a number of alternative approaches for solar space and water heating were identified from interviews with individuals and groups involved in solar retrofit projects in the Boston area. The objective was to identify approaches that many of those interviewed believe to be low-cost means of applying solar energy in residential settings. The approaches selected include thermal window covers, wall collectors, bread box water heaters, and sun spaces. Preliminary estimates of the performance of several representative designs were developed and the economics of these designs evaluated.

  6. Solar Power Sources: PV, Concentrated PV, and Concentrated Solar Power

    DEFF Research Database (Denmark)

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

    2017-01-01

    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 a s...

  7. Solar Cooling System Using Solar-Driven Hybrid Chiller

    OpenAIRE

    Hirai, Akira

    2012-01-01

    We developed an appropriate Absorption chiller to "Solar cooling system" in 2010. In addition, we added the improvement to the machine. "Solar cooling system" can be easily constructed with the machine. and, we constructed the demonstration plant, and verified the utility

  8. Solar-hydrogen generation and solar concentration (Conference Presentation)

    NARCIS (Netherlands)

    Chinello, Enrico; 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; Sulima, Oleg V.; Conibeer, Gavin

    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 p

  9. Solar Flares: Magnetohydrodynamic Processes

    Directory of Open Access Journals (Sweden)

    Kazunari Shibata

    2011-12-01

    Full Text Available This paper outlines the current understanding of solar flares, mainly focused on magnetohydrodynamic (MHD processes responsible for producing a flare. Observations show that flares are one of the most explosive phenomena in the atmosphere of the Sun, releasing a huge amount of energy up to about 10^32 erg on the timescale of hours. Flares involve the heating of plasma, mass ejection, and particle acceleration that generates high-energy particles. The key physical processes for producing a flare are: the emergence of magnetic field from the solar interior to the solar atmosphere (flux emergence, local enhancement of electric current in the corona (formation of a current sheet, and rapid dissipation of electric current (magnetic reconnection that causes shock heating, mass ejection, and particle acceleration. The evolution toward the onset of a flare is rather quasi-static when free energy is accumulated in the form of coronal electric current (field-aligned current, more precisely, while the dissipation of coronal current proceeds rapidly, producing various dynamic events that affect lower atmospheres such as the chromosphere and photosphere. Flares manifest such rapid dissipation of coronal current, and their theoretical modeling has been developed in accordance with observations, in which numerical simulations proved to be a strong tool reproducing the time-dependent, nonlinear evolution of a flare. We review the models proposed to explain the physical mechanism of flares, giving an comprehensive explanation of the key processes mentioned above. We start with basic properties of flares, then go into the details of energy build-up, release and transport in flares where magnetic reconnection works as the central engine to produce a flare.

  10. Solar Magnetic Flux Ropes

    Indian Academy of Sciences (India)

    Boris Filippov; Olesya Martsenyuk; Abhishek K. Srivastava; Wahab Uddin

    2015-03-01

    In the early 1990s, it was found that the strongest disturbances of the space–weather were associated with huge ejections of plasma from the solar corona, which took the form of magnetic clouds when moved from the Sun. It is the collisions of the magnetic clouds with the Earth's magnetosphere that lead to strong, sometimes catastrophic changes in space–weather. The onset of a coronal mass ejection (CME) is sudden and no reliable forerunners of CMEs have been found till date. The CME prediction methodologies are less developed compared to the methods developed for the prediction of solar flares. The most probable initial magnetic configuration of a CME is a flux rope consisting of twisted field lines which fill the whole volume of a dark coronal cavity. The flux ropes can be in stable equilibrium in the coronal magnetic field for weeks and even months, but suddenly they lose their stability and erupt with high speed. Their transition to the unstable phase depends on the parameters of the flux rope (i.e., total electric current, twist, mass loading, etc.), as well as on the properties of the ambient coronal magnetic field. One of the major governing factors is the vertical gradient of the coronal magnetic field, which is estimated as decay index (). Cold dense prominence material can be collected in the lower parts of the helical flux tubes. Filaments are, therefore, good tracers of the flux ropes in the corona, which become visible long before the beginning of the eruption. The perspectives of the filament eruptions and following CMEs can be estimated by a comparison of observed filament heights with calculated decay index distributions. The present paper reviews the formation of magnetic flux ropes, their stable and unstable phases, eruption conditions, and also discusses their physical implications in the solar corona.

  11. Solar Thermal Concept Evaluation

    Science.gov (United States)

    Hawk, Clark W.; Bonometti, Joseph A.

    1995-01-01

    Concentrated solar thermal energy can be utilized in a variety of high temperature applications for both terrestrial and space environments. In each application, knowledge of the collector and absorber's heat exchange interaction is required. To understand this coupled mechanism, various concentrator types and geometries, as well as, their relationship to the physical absorber mechanics were investigated. To conduct experimental tests various parts of a 5,000 watt, thermal concentrator, facility were made and evaluated. This was in anticipation at a larger NASA facility proposed for construction. Although much of the work centered on solar thermal propulsion for an upper stage (less than one pound thrust range), the information generated and the facility's capabilities are applicable to material processing, power generation and similar uses. The numerical calculations used to design the laboratory mirror and the procedure for evaluating other solar collectors are presented here. The mirror design is based on a hexagonal faceted system, which uses a spherical approximation to the parabolic surface. The work began with a few two dimensional estimates and continued with a full, three dimensional, numerical algorithm written in FORTRAN code. This was compared to a full geometry, ray trace program, BEAM 4, which optimizes the curvatures, based on purely optical considerations. Founded on numerical results, the characteristics of a faceted concentrator were construed. The numerical methodologies themselves were evaluated and categorized. As a result, the three-dimensional FORTRAN code was the method chosen to construct the mirrors, due to its overall accuracy and superior results to the ray trace program. This information is being used to fabricate and subsequently, laser map the actual mirror surfaces. Evaluation of concentrator mirrors, thermal applications and scaling the results of the 10 foot diameter mirror to a much larger concentrator, were studied. Evaluations

  12. Concentrated Solar Thermoelectric Power

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Gang [MIT; Ren, Zhifeng [University of Houston

    2015-07-09

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

  13. Solar Thermal Electricity Generating System

    Science.gov (United States)

    Mishra, Sambeet; Tripathy, Pratyasha

    2012-08-01

    A Solar Thermal Electricity generating system also known as Solar Thermal Power plant is an emerging renewable energy technology, where we generate the thermal energy by concentrating and converting the direct solar radiationat medium/high temperature (300∫C ñ 800∫C). The resulting thermal energy is then used in a thermodynamic cycleto produce electricity, by running a heat engine, which turns a generator to make electricity. Solar thermal power is currently paving the way for the most cost-effective solar technology on a large scale and is heading to establish a cleaner, pollution free and secured future. Photovoltaic (PV) and solar thermal technologies are two main ways of generating energy from the sun, which is considered the inexhaustible source of energy. PV converts sunlight directly into electricity whereas in Solar thermal technology, heat from the sun's rays is concentrated to heat a fluid, whose steam powers a generator that produces electricity. It is similar to the way fossil fuel-burning power plants work except that the steam is produced by the collected heat rather than from the combustion of fossil fuels. In order to generate electricity, five major varieties of solar thermal technologies used are:* Parabolic Trough Solar Electric Generating System (SEGS).* Central Receiver Power Plant.* Solar Chimney Power Plant.* Dish Sterling System.* Solar Pond Power Plant.Most parts of India,Asia experiences a clear sunny weather for about 250 to 300 days a year, because of its location in the equatorial sun belt of the earth, receiving fairly large amount of radiation as compared to many parts of the world especially Japan, Europe and the US where development and deployment of solar technologies is maximum.Whether accompanied with this benefit or not, usually we have to concentrate the solar radiation in order to compensate for the attenuation of solar radiation in its way to earthís surface, which results in from 63,2 GW/m2 at the Sun to 1 kW/m2 at

  14. Detection of solar events

    Science.gov (United States)

    Fischbach, Ephraim; Jenkins, Jere

    2013-08-27

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

  15. The solar system

    CERN Document Server

    Jones, B W

    2013-01-01

    Presents a contemporary picture of the solar system, including a description of the Earth, Mars, Venus, cratered worlds, exotic rocks and ices, and giant planets. It is pitched at an introductory level and assumes no previous knowledge of planetary astronomy. Little mathematics is used in the text and the numerous graphs and diagrams are kept as simple as possible. End of chapter exercises are provided. The book can be used as an end in itself, or as a preparation for more advanced study, for which references are given.

  16. Microanalysis of Solar Cells

    Science.gov (United States)

    Kazmerski, Lawrence L.

    1980-11-01

    Applications of complementary surface analysis techniques (AES, SIMS, XPS) to solar cell device problems are discussed. Several examples of device interface and grain boundary problems are presented. Silicon, gallium arsenide and indium phosphide based devices are reviewed. Results of compositional and chemical analysis are correlated directly with EBIC measurements performed in-situ on identical sample areas. Those are, in turn, correlated with resulting photovoltaic device performance. The importance of microanalysis to the solution of critical device problems in the photovoltaics technology is emphasized.

  17. Solar Power in Space?

    Science.gov (United States)

    2012-01-01

    that support its missions and users. Only the small secrets need to be protected. The large ones are kept secret by public incredulity. — Marshall ... McLuhan With such obvious benefits for the nation and so many potential stake- holders, one would think it easy to move forward, but it is not. SBSP Solar...impossible.” —Lord Kelvin, President of the Royal Society “Airplanes are interesting toys of no military value.” — Marshal Ferdinand Foch, Ecole

  18. Silicon heterojunction solar cells

    CERN Document Server

    Fahrner, W R; Neitzert, H C

    2006-01-01

    The world of today must face up to two contradictory energy problems: on the one hand, there is the sharply growing consumer demand in countries such as China and India. On the other hand, natural resources are dwindling. Moreover, many of those countries which still possess substantial gas and oil supplies are politically unstable. As a result, renewable natural energy sources have received great attention. Among these, solar-cell technology is one of the most promising candidates. However, there still remains the problem of the manufacturing costs of such cells. Many attempts have been made

  19. Solar pannels tracking systems

    Energy Technology Data Exchange (ETDEWEB)

    Manuel, P.; Maire, J.; Chollet, C.; Rohee, S.; Vialettes, J.M.

    1984-11-23

    This patent is concerned with a steering device for solar photo-pannels laid in row in order to minimize the cast shadow of each pannel on the others, while maintaining a required land use (the pannels are disposed according to a centered hexagonal lattice). The device is designed to set a whole row of pannels according to the azimuthal orientation of the sun. It is composed of a set of (at least) two side rod drives situated at each side of the row and coupled to the pannel. The pannels are moved by the action of two (or more) traction ropes.

  20. Innovative Solar Optical Materials

    Science.gov (United States)

    Lampert, Carl M.

    1984-02-01

    A variety of optical coatings are discussed in the context of solar energy utilization. Well-known coatings such as transparent conductors (heat mirrors), selective absorbers, and reflective films are surveyed briefly. Emphasis is placed on the materials' limitations and on use of lesser-known optical coatings and materials. Physical and optical properties are detailed for protective antireflection films, cold mirrors, fluorescent concentrator materials, radiative cooling surfaces, and optical switching films including electrochromic, thermochromic, photochromic, and liquid crystal types. For many of these materials, research has only recently been considered, so various design and durability issues need to be addressed.