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1

A Photoelectrochemical Solar Cell: An Undergraduate Experiment.  

ERIC Educational Resources Information Center

Preparation and testing of a cadmium selenide photoelectrical solar cell was introduced into an environmental chemistry course to illustrate solid state semiconductor and electrochemical principles. Background information, procedures, and results are provided for the experiment which can be accomplished in a three- to four-hour laboratory session…

Boudreau, Sharon M.; And Others

1983-01-01

2

Concentrator solar cell array technology flight experiment  

Microsoft Academic Search

A flight experiment has been planned to study the suitability of a new concentrator solar array technology for satellite applications. This paper briefly describes the design and testing of the experiment. By the end of March 2002, Space Systems\\/Loral (SS\\/L) completed the testing of the flight coupon panel under various space environment conditions. The experiment is under integration and will

R. K. Jain; Yu Nang Wong; J. Kesapradist; G. van Ommering; M. Eskenazi

2002-01-01

3

Gallium Arsenide solar cell radiation damage experiment  

NASA Technical Reports Server (NTRS)

Gallium arsenide (GaAs) solar cells for space applications from three different manufactures were irradiated with 10 MeV protons or 1 MeV electrons. The electrical performance of the cells was measured at several fluence levels and compared. Silicon cells were included for reference and comparison. All the GaAs cell types performed similarly throughout the testing and showed a 36 to 56 percent power areal density advantage over the silicon cells. Thinner (8-mil versus 12-mil) GaAs cells provide a significant weight reduction. The use of germanium (Ge) substrates to improve mechanical integrity can be implemented with little impact on end of life performance in a radiation environment.

Maurer, R. H.; Kinnison, J. D.; Herbert, G. A.; Meulenberg, A.

1991-01-01

4

TACSAT-4 solar cell experiment: Advanced solar cell technologies in a high radiation environment  

Microsoft Academic Search

The TACSAT-4 Solar Cell Experiment will measure the current and voltage characteristics of advanced EMCORE BTJM solar cells thinned to 100 microns and ATJM cells under an 8.5X ENTECH Stretched Lens. TACSAT-4 will fly in a highly elliptical orbit, passing through the electron and proton belts every six hours. This orbit is expected to induce a 25% power reduction in

Phillip Jenkins; Michael Krasowski; Norman Prokop; Robert Walters; D. Spina; M. Eskenazi; R. Skalitzky; T. Duffey; B. Davis; S. Koss; S. Messenger; E. Downard; K. Crist; M. O'Neill; B. Fu; D. Bentz

2009-01-01

5

Summary results of the ATS-6 solar cell flight experiment  

NASA Technical Reports Server (NTRS)

Synchronous orbit performance data are analyzed for solar cells of 13 different configurations involved in the ATS-6 solar cell radiation damage experiment. It is found that the cells generally performed as expected through 6 to 9 months in orbit, but that after 2-1/3 years were more severely degraded in current than expected. An anomalous additional degradation of 5-9% in short circuit current has been observed for some cells.

Goldhammer, L. J.; Slifer, L. W., Jr.

1980-01-01

6

Experience in Manufacturing GaAs Space Solar Cells.  

National Technical Information Service (NTIS)

Experience acquired in establishing a manufacturing process for GaAs solar cells for use on spacecraft is summarized. Process selection, the build-up of equipment and material support, and the results achieved are described.

P. A. Iles Y. C. M. Yeh F. H. Ho K. Chang

1986-01-01

7

Mars Array Technology Experiment (MATE) [space power solar cell performance  

Microsoft Academic Search

Airborne and settled dust on the surface of Mars alters the sunlight and fluctuates from day to day, it affects both the intensity and spectral content. Future missions to Mars are considering solar power and therefore solar cell technologies must be evaluated to find the optimum. The MATE flight experiment was designed for this purpose as part of the Mars

David A. Scheiman; Phillip Jenkins; Geoffrey A. Landis; C. Baraona; D. Wilt; M. Krasowski; L. Greer; J. Lekki; D. Spina

2000-01-01

8

A Dust Characterization Experiment for Solar Cells Operating on Mars  

NASA Technical Reports Server (NTRS)

During the Viking and Pathfinder missions to Mars, significant amounts of dust accumulated on the spacecrafts. In Pathfinder's case, the dust obscured the solar panels on the lander and the rover degrading their output current. The material adherence experiment aboard the Pathfinder rover quantified the rate of decrease in short circuit current at 0.28% per day. This rate is unacceptably high for long duration missions. In response, NASA has developed the Dust Accumulation and Removal Technology (DART) experiment. DART has three instruments for characterizing dust settling out of the atmosphere and tests two methods to keep dust from settling on solar cells.

Jenkins, Phillip; Landis, Geoffrey A.; Krasowski, Michael; Greer, Lawrence; Wilt, David; Baraona, Cosmo; Scheiman, David; Lekki, John

2001-01-01

9

AFRL Thin Film Solar Cell Development and Upcoming Flight Experiments  

Microsoft Academic Search

The many advantages of thin film solar cells, namely flexibility, high radiation resistance, low mass, and low cost production, will go untapped until space environmental effects on them are well understood, which requires on-orbit testing. In response to the need to perform on-orbit testing of thin film solar cells, the Space Vehicles Directorate of the Air Force Research Laboratory (AFRL)

Jennifer E. Granata; Paul E. Hausgen; Donna Senft; Pawel Tlomak; John Merrill

2005-01-01

10

Organic solar cells: How can the theory guide the experience?  

NASA Astrophysics Data System (ADS)

Research in organic photovoltaic applications are receiving a great interest in the last few years as they offer an environmentally clean and low-cost solution to the world's rising energy needs. One of the main problems limiting the efficiency of an organic solar cell device is the strong binding energy of the excitons, typically of a few hundreds of meV, which is ten to one hundred times more than in inorganic devices. Another limiting factor, persistent in P3HT:PCBM devices, can be the misalignment of the the HOMO (Highest Occupied Molecular Orbital) and the LUMO (Lowest Unoccupied Molecular Orbital) energy levels of the different components of the solar cell. Scharber's model (Scharber, M.C., Adv. Mater. 18, 789) is a simple yet interesting approach for predicting the efficiency of those devices, mainly based on the values of the HOMO and the LUMO and reasonable assumptions for the exciton binding energy. In this presentation, we will discuss how theoretical calculations based on density-functional theory can provide a guide to find promising polymers for photovoltaic cells. The accuracy, limits and possible expansions of Scharber's model will be examined, and a number of interesting polymer candidates to reach and perhaps break the well-known 10 % efficiency will be presented.

Berube, Nicolas; Gosselin, Vincent; Lepage, Hugo; Cote, Michel

2012-02-01

11

Solar array flight experiment  

NASA Technical Reports Server (NTRS)

Emerging satellite designs require increasing amounts of electrical power to operate spacecraft instruments and to provide environments suitable for human habitation. In the past, electrical power was generated by covering rigid honeycomb panels with solar cells. This technology results in unacceptable weight and volume penalties when large amounts of power are required. To fill the need for large-area, lightweight solar arrays, a fabrication technique in which solar cells are attached to a copper printed circuit laminated to a plastic sheet was developed. The result is a flexible solar array with one-tenth the stowed volume and one-third the weight of comparably sized rigid arrays. An automated welding process developed to attack the cells to the printed circuit guarantees repeatable welds that are more tolerant of severe environments than conventional soldered connections. To demonstrate the flight readiness of this technology, the Solar Array Flight Experiment (SAFE) was developed and flown on the space shuttle Discovery in September 1984. The tests showed the modes and frequencies of the array to be very close to preflight predictions. Structural damping, however, was higher than anticipated. Electrical performance of the active solar panel was also tested. The flight performance and postflight data evaluation are described.

1986-01-01

12

Germany's Solar Experiment  

NSDL National Science Digital Library

This NOVA video podcast is about Germany's solar experiment. Munich's solar panel farm lines the Autobahn and countryside in a massive effort to prove solar's feasibility as a practical renewable energy source.

Nova

13

Results of the first 150 days of the NTS-1 solar cell experiments  

NASA Technical Reports Server (NTRS)

Twelve solar cell experiments were on the Naval Research Laboratory NTS-1 satellite launched on 14 July 1974, into a 13,260 km circular orbit at an inclination of 125 deg. The experiment comprises: 2 ohm-cm n/p, lithium-diffused p/n, violet n/p, p(+) back surface field, and ultra-thin wrap around contact cells. The short-circuit current of the experiments ranged from 2 to 12 percent higher in space than under solar simulators. During the 5 year life of the satellite, the experiments will be exposed to radiation equivalent to 2 x 10 to the 15th power 1-MeV electron cm/2 and to nearly 5500 thermal cycles.

Statler, R. L.

1974-01-01

14

Analysis of space environment damage to solar cell assemblies from LDEF experiment A0171-GSFC test plate  

NASA Technical Reports Server (NTRS)

The results of the postflight analysis of the solar cell assemblies from the LDEF (Long Duration Exposure facility) experiment A0171 is provided in this NASA sponsored research project. The following data on this research are provided as follows: (1) solar cell description, including, substrate composition and thickness, crystal orientation, anti-reflective coating composition and thickness; (2) preflight characteristics of the solar cell assemblies with respect to current and voltage; and (3) post-flight characteristics of the solar cell assemblies with respect to voltage and current. These solar cell assemblies are part of the Goddard Space Flight Center test plate which was designed to test the space environment effects (radiation, atomic oxygen, thermal cycling, meteoroid and debris) on conductively coated solar cell coversheets, various electrical bond materials, solar cell performance, and other material properties where feasible.

Hill, David C.; Rose, M. Frank

1994-01-01

15

Displacement Damage Effects in Solar Cells: Mining Damage From the Microelectronics and Photonics Test Bed Space Experiment  

NASA Technical Reports Server (NTRS)

The objective is to develop an improved space solar cell radiation response analysis capability and to produce a computer modeling tool which implements the analysis. This was accomplished through analysis of solar cell flight data taken on the Microelectronics and Photonics Test Bed experiment. This effort specifically addresses issues related to rapid technological change in the area of solar cells for space applications in order to enhance system performance, decrease risk, and reduce cost for future missions.

Hardage, Donna (Technical Monitor); Walters, R. J.; Morton, T. L.; Messenger, S. R.

2004-01-01

16

Molybdenum solar neutrino experiment  

Microsoft Academic Search

The molybdenum solar neutrino experiment goal is to deduce the (8)B solar neutrino flux, averaged over the past several million years, from the concentration of (98)Tc in a deeply buried molybdenum deposit. It is important because it will shed light on the reason for the discrepancy between theory and observation of the chlorine solar neutrino experiment. It is suggested that

K. Wolfsberg; G. A. Cowan; E. A. Bryant; K. S. Daniels; S. W. Downey; W. C. Haxton; V. G. Niesen; N. S. Nogar; C. M. Miller; D. J. Rokop

1984-01-01

17

Final results from the MISSE5 GaAs on Si solar cell experiment  

Microsoft Academic Search

GaAs on Si (GaAs\\/Si) solar cells with AM0 efficiencies in excess of 17% have been demonstrated using Si substrates coated with a step-graded buffer of SixGe1-x alloys graded to 100% Ge. A year of LEO testing of this technology aboard Materials International Space Station Experiment number 5 (MISSE5) was recently competed. Electrical performance data, sun angle and thermal conditions measured

David M. Wilt; AnnaMaria T. Pal; Steven A. Ringel; Eugene A. Fitzgerald; Phillip P. Jenkins; Robert Walters

2008-01-01

18

Solar Cells  

NASA Technical Reports Server (NTRS)

The Heat Exchanger Method (HEM) produces high efficiency crystal ingots in an automated well-insulated furnace offering low equipment, labor and energy costs. The "grown" silicon crystals are used to make solar cells, or photovoltaic cells which convert sunlight directly into electricity. The HEM method is used by Crystal Systems, Inc. and was developed under a NASA/Jet Propulsion Laboratory contract. The square wafers which are the result of the process are sold to companies manufacturing solar panels.

1983-01-01

19

Two years of on-orbit gallium arsenide performance from the LIPS solar cell panel experiment  

NASA Technical Reports Server (NTRS)

The LIPS on-orbit performance of the gallium arsenide panel experiment was analyzed from flight operation telemetry data. Algorithms were developed to calculate the daily maximum power and associated solar array parameters by two independent methods. The first technique utilizes a least mean square polynomial fit to the power curve obtained with intensity and temperature corrected currents and voltages; whereas, the second incorporates an empirical expression for fill factor based on an open circuit voltage and the calculated series resistance. Maximum power, fill factor, open circuit voltage, short circuit current and series resistance of the solar cell array are examined as a function of flight time. Trends are analyzed with respect to possible mechanisms which may affect successive periods of output power during 2 years of flight operation. Degradation factors responsible for the on-orbit performance characteristics of gallium arsenide are discussed in relation to the calculated solar cell parameters. Performance trends and the potential degradation mechanisms are correlated with existing laboratory and flight data on both gallium arsenide and silicon solar cells for similar environments.

Francis, R. W.; Betz, F. E.

1985-01-01

20

Two years of on-orbit gallium arsenide performance from the LIPS solar cell panel experiment  

NASA Astrophysics Data System (ADS)

The LIPS on-orbit performance of the gallium arsenide panel experiment was analyzed from flight operation telemetry data. Algorithms were developed to calculate the daily maximum power and associated solar array parameters by two independent methods. The first technique utilizes a least mean square polynomial fit to the power curve obtained with intensity and temperature corrected currents and voltages; whereas, the second incorporates an empirical expression for fill factor based on an open circuit voltage and the calculated series resistance. Maximum power, fill factor, open circuit voltage, short circuit current and series resistance of the solar cell array are examined as a function of flight time. Trends are analyzed with respect to possible mechanisms which may affect successive periods of output power during 2 years of flight operation. Degradation factors responsible for the on-orbit performance characteristics of gallium arsenide are discussed in relation to the calculated solar cell parameters. Performance trends and the potential degradation mechanisms are correlated with existing laboratory and flight data on both gallium arsenide and silicon solar cells for similar environments.

Francis, R. W.; Betz, F. E.

21

Materials on the International Space Station - Forward Technology Solar Cell Experiment  

NASA Technical Reports Server (NTRS)

This paper describes a space solar cell experiment currently being built by the Naval Research Laboratory (NRL) in collaboration with NASA Glenn Research Center (GRC), and the US Naval Academy (USNA). The experiment has been named the Forward Technology Solar Cell Experiment (FTSCE), and the purpose is to rapidly put current and future generation space solar cells on orbit and provide validation data for these technologies. The FTSCE is being fielded in response to recent on-orbit and ground test anomalies associated with space solar arrays that have raised concern over the survivability of new solar technologies in the space environment and the validity of present ground test protocols. The FTSCE is being built as part of the Fifth Materials on the International Space Station (MISSE) Experiment (MISSE-5), which is a NASA program to characterize the performance of new prospective spacecraft materials when subjected to the synergistic effects of the space environment. Telemetry, command, control, and communication (TNC) for the FTSCE will be achieved through the Amateur Satellite Service using the PCSat2 system, which is an Amateur Radio system designed and built by the USNA. In addition to providing an off-the-shelf solution for FTSCE TNC, PCSat2 will provide a communications node for the Amateur Radio satellite system. The FTSCE and PCSat2 will be housed within the passive experiment container (PEC), which is an approximately 2ft x2ft x 4in metal container built by NASA Langley Research Center (NASA LaRC) as part of the MISSE-5 program. NASA LaRC has also supplied a thin film materials experiment that will fly on the exterior of the thermal blanket covering the PCSat2. The PEC is planned to be transported to the ISS on a Shuttle flight. The PEC will be mounted on the exterior of the ISS by an astronaut during an extravehicular activity (EVA). After nominally one year, the PEC will be retrieved and returned to Earth. At the time of writing this paper, the subsystems of the experiment are being integrated at NRL, and we are preparing to commence environmental testing.

Walters, R. J.; Garner, J. C.; Lam, S. N.; Vazquez, J. A.; Braun, W. R.; Ruth, R. E.; Lorentzen, J. R.; Bruninga, R.; Jenkins, P. P.; Flatico, J. M.

2005-01-01

22

Solar experiment alignment system  

NASA Technical Reports Server (NTRS)

Sensor system determines absolute alignment of optical axis of experiment package relative to solar vector and provides control information to permit pointing experiment anywhere on solar disc to absolute accuracy of the order of two arc seconds in center and five arc seconds on limb.

Fain, D. L.

1972-01-01

23

Molybdenum Solar Neutrino Experiment.  

National Technical Information Service (NTIS)

The goal of the molybdenum solar neutrino experiment is to deduce the sup 8 B solar neutrino flux, averaged over the past several million years, from the concentration of sup 98 Tc in a deeply buried molybdenum deposit. The experiment is important to an u...

K. Wolfsberg G. A. Cowan E. A. Bryant K. S. Daniels S. W. Downey

1984-01-01

24

Radiation effects on solar cells: experiments, models, and simulations: DLTS vs. SRIM for trap data  

NASA Astrophysics Data System (ADS)

A predictive computational approach that limits use of DLTS experiments is presented, developed using the experimental data and proposed physics based models. Three-dimensional NanoTCAD simulations are used for physicsbased prediction of space radiation effects in III-V solar cells, and validated with experimentally measured characteristics of a p+n GaAs solar cell with AlGaAs window. The computed dark and illuminated I-V curves as well as corresponding performance parameters matched very well experimental data for 2 MeV proton irradiation at various fluences. We analyze the role of majority vs. minority and deep vs. shallow carrier traps in the solar cell performance degradation. The traps/defects parameters used in the simulations were derived from Deep Level Transient Spectroscopy (DLTS) data obtained at NRL. It was noticed that the degradation caused by deep traps observed in single-trap numerical tests exhibit a very similar trend to the degradation caused by a full spectrum of defect traps, but to a lesser degree. This led to the development of a method to accurately simulate the degradation of a solar cell by using only a single deep level defect whose density is calculated by the Stopping and Range of Ions in Matter (SRIM) code. Using SRIM, we calculated the number of vacancies produced by 2 MeV proton irradiation for fluences ranging from 6x1010 cm-2 to 5x1012 cm-2. Based on the SRIM results, we applied trap models in NanoTCAD and performed full I-V simulations from which the amount of degradation of performance parameters (Isc, Voc, Pmax) was calculated. The physics-based models using SRIM allowed obtaining good match with experimental data.

Fedoseyev, Alex; Turowski, Marek; Bald, Timothy; Raman, Ashok; Warner, Jeffrey H.

2013-09-01

25

Solar cells  

NASA Astrophysics Data System (ADS)

The history, state of the art, and future prospects of solar cells are reviewed. Solar cells are already competitive in a wide range of low-power applications, and during the 1980's they are expected to become cheaper to run than diesel or gasoline generators, the present mainstay of isolated communities. At this stage they will become attractive for water pumping, irrigation, and rural electrification, particularly in developing countries. With further cost reduction, they may be used to augment grid supplies in domestic, commercial, institutional, and industrial premises. Cost reduction to the stage where photovoltaics becomes economic for large-scale power generation in central stations depends on a technological breakthrough in the development of thin-film cells. DOE aims to reach this goal by 1990, so that by the end of the century about 20% of the estimated annual additions to their electrical generating capacity will be photovoltaic.

Treble, F. C.

1980-11-01

26

Molybdenum solar neutrino experiment  

NASA Astrophysics Data System (ADS)

The molybdenum solar neutrino experiment goal is to deduce the (8)B solar neutrino flux, averaged over the past several million years, from the concentration of (98)Tc in a deeply buried molybdenum deposit. It is important because it will shed light on the reason for the discrepancy between theory and observation of the chlorine solar neutrino experiment. It is suggested that possible reasons for the discrepancy lie in the properties of neutrinos or in deficiencies of the standard solar model. The chlorine experiment only measures the (8)B neutrino flux in current times. In the molybdenum experiments, (98)Tc (4.2 Myr) are measured, which are produced by (8)B neutrinos, and possibly (97)Tc (2.6 Myr), produced by lower energy neutrinos.

Wolfsberg, K.; Cowan, G. A.; Bryant, E. A.; Daniels, K. S.; Downey, S. W.; Haxton, W. C.; Niesen, V. G.; Nogar, N. S.; Miller, C. M.; Rokop, D. J.

27

Solar cell  

US Patent & Trademark Office Database

The invention relates to a solar cell that comprises a planar semiconductor substrate with a front and a back; a multitude of holes that interconnect the front and the back; and current-collecting electrical contacts that are exclusively arranged on the back. The front comprises highly doped regions and lightly doped regions of a first type such that in each case the holes are situated in a highly doped region or adjoin such a region. According to a first aspect of the invention, the highly doped regions are arranged locally around the holes. According to a second aspect of the invention, the front comprises at least one region without holes, and the highly doped regions comprise one region or several regions that extends/extend to the at least one hole-free region. The invention furthermore relates to methods for manufacturing such solar cells.

2010-12-14

28

Photoelectrochemical Solar Cells.  

ERIC Educational Resources Information Center

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…

McDevitt, John T.

1984-01-01

29

The effect of the low Earth orbit environment on space solar cells: Results of the advanced photovoltaic experiment (S0014)  

NASA Technical Reports Server (NTRS)

The Advanced Photovoltaic Experiment (APEX), containing over 150 solar cells and sensors, was designed to generate laboratory reference standards as well as to explore the durability of a wide variety of space solar cells. Located on the leading edge of the Long Duration Exposure Facility (LDEF), APEX received the maximum possible dosage of atomic oxygen and ultraviolet radiation, as well as enormous numbers of impacts from micrometeoroids and debris. The effect of the low earth orbital (LEO) environment on the solar cells and materials of APEX will be discussed in this paper. The on-orbit performance of the solar cells, as well as a comparison of pre- and postflight laboratory performance measurements, will be presented.

Brinker, David J.; Hickey, John R.

1992-01-01

30

Simple Experiments on the Use of Solar Energy  

ERIC Educational Resources Information Center

Describes 5 solar energy experiments that can be used in secondary school: flat-plate collector, solar thermoelectric generator, simple concentrators, solar cell, and natural storage of solar energy. (MLH)

Vella, G. J.; Goldsmid, H. J.

1976-01-01

31

Solar neutrino experiments  

Microsoft Academic Search

Observational methods for detecting solar neutrinos are reviewed, and the current results presented. Four operating systems, the Homestake Mine Cl-37 radio-chemical method, the real-time neutrino scattering detector at Kamiokande II, in Japan, and two radiochemical gallium-germanium experiments are discussed in some detail. The results from these operating detectors are compared to solar model calculations and various neutrino neutrino oscillation processes

Raymond Davis Jr.; Arthur N. Cox

1991-01-01

32

Forward Technology Solar Cell Experiment (FTSCE) for MISSE-5 Verified and Readied for Flight on STS-114  

NASA Technical Reports Server (NTRS)

The Forward Technology Solar Cell Experiment (FTSCE) is a space solar cell experiment built as part of the Fifth Materials on the International Space Station Experiment (MISSE-5): Data Acquisition and Control Hardware and Software. It represents a collaborative effort between the NASA Glenn Research Center, the Naval Research Laboratory, and the U.S. Naval Academy. The purpose of this experiment is to place current and future solar cell technologies on orbit where they will be characterized and validated. This is in response to recent on-orbit and ground test results that raised concerns about the in-space survivability of new solar cell technologies and about current ground test methodology. The various components of the FTSCE are assembled into a passive experiment container--a 2- by 2- by 4-in. folding metal container that will be attached by an astronaut to the outer structure of the International Space Station. Data collected by the FTSCE will be relayed to the ground through a transmitter assembled by the U.S. Naval Academy. Data-acquisition electronics and software were designed to be tolerant of the thermal and radiation effects expected on orbit. The experiment has been verified and readied for flight on STS-114.

Jenkins, Phillip P.; Krasowski, Michael J.; Greer, Lawrence C.; Flatico, Joseph M.

2005-01-01

33

Radiochemical solar neutrino experiments  

NASA Astrophysics Data System (ADS)

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++?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 67.3-3.5+3.9 SNU. Using the data from all solar neutrino experiments we calculate an electron neutrino pp flux of ?pp?=(3.41-0.77+0.76)×1010/(cm-s), which agrees well with the prediction from a detailed solar model of ?pp?=(3.30-0.14+0.13)×1010/(cm-s). Four tests of the Ga experiments have been carried out with very intense reactor-produced neutrino sources and the ratio of observed to calculated rates is 0.88±0.05. One explanation for this unexpectedly low result is that the cross section for neutrino capture by the two lowest-lying excited states in 71Ge has been overestimated. We end with consideration of possible time variation in the Ga experiments and an enumeration of other possible radiochemical experiments that might have been.

Gavrin, V. N.; Cleveland, B. T.

2011-12-01

34

Molybdenum solar neutrino experiment  

SciTech Connect

The goal of the molybdenum solar neutrino experiment is to deduce the /sup 8/B solar neutrino flux, averaged over the past several million years, from the concentration of /sup 98/Tc in a deeply buried molybdenum deposit. The experiment is important to an understanding of stellar processes because it will shed light on the reason for the discrepancy between theory and observation of the chlorine solar neutrino experiment. Possible reasons for the discrepancy may lie in the properties of neutrinos (neutrino oscillations or massive neutrinos) or in deficiencies of the standard solar model. The chlorine experiment only measures the /sup 8/B neutrino flux in current times and does not address possible temporal variations in the interior of the sun, which are also not considered in the standard model. In the molybdenum experiment, we plan to measure /sup 98/Tc (4.2 Myr), also produced by /sup 8/B neutrinos, and possibly /sup 97/Tc (2.6 Myr), produced by lower energy neutrinos.

Wolfsberg, K.; Cowan, G.A.; Bryant, E.A.; Daniels, K.S.; Downey, S.W.; Haxton, W.C.; Niesen, V.G.; Nogar, N.S.; Miller, C.M.; Rokop, D.J.

1984-01-01

35

NASA solar array flight experiment  

NASA Astrophysics Data System (ADS)

The NASA large flexible solar array space shuttle flight experiment is described. The 32 x 4 m wing is deployed from the shuttle bay, and experiments in electrical output, multiple deployment, and structural dynamics are planned. Both 2 x 4 cm and 5.9 x 5.9 cm cell assemblies on the array blanket are evaluated. Safety/hazards provisions are described, including emergency jettison provisions. Ground testing and hardware fabrication are summarized.

Turner, G.; Hill, H.

1982-06-01

36

NASA solar array flight experiment  

NASA Technical Reports Server (NTRS)

The NASA large flexible solar array space shuttle flight experiment is described. The 32 x 4 m wing is deployed from the shuttle bay, and experiments in electrical output, multiple deployment, and structural dynamics are planned. Both 2 x 4 cm and 5.9 x 5.9 cm cell assemblies on the array blanket are evaluated. Safety/hazards provisions are described, including emergency jettison provisions. Ground testing and hardware fabrication are summarized.

Turner, G.; Hill, H.

1982-01-01

37

Solar cell degradation observed by the Advanced Photovoltaic and Electronics experiments (APEX) satellite  

Microsoft Academic Search

This paper presents results from the Photovoltaic Array Space Power Plus Diagnostics (PASP Plus) experiment flown on board the Advanced Photovoltaic and Electronics experiment (APEX) satellite launched on 3 August 1994 into a 2552 km×363 km orbit with a 70° inclination. Results presented are based on 4576 orbits of data from 3 August 1994 to 11 August 1995. Fifteen solar

K. P. Ray; D. E. Delorey; E. G. Mullen; D. A. Guidice; D. C. Marvin; H. B. Curtis; M. F. Piszczor

1996-01-01

38

Laser annealing of amorphous/poly: Silicon solar cell material flight experiment  

NASA Technical Reports Server (NTRS)

The preliminary design proposed for the microelectronics materials processing equipment is presented. An overall mission profile, description of all processing steps, analysis methods and measurement techniques, data acquisition and storage, and a preview of the experimental hardware are included. The goal of the project is to investigate the viability of material processing of semiconductor microelectronics materials in a micro-gravity environment. The two key processes are examined: (1) Rapid Thermal Annealing (RTA) of semiconductor thin films and damaged solar cells, and (2) thin film deposition using a filament evaporator. The RTA process will be used to obtain higher quality crystalline properties from amorphous/poly-silicon films. RTA methods can also be used to repair radiation-damaged solar cells. On earth this technique is commonly used to anneal semiconductor films after ion-implantation. The damage to the crystal lattice is similar to the defects found in solar cells which have been exposed to high-energy particle bombardment.

Cole, Eric E.

1990-01-01

39

Solar cells for solar power satellites  

NASA Technical Reports Server (NTRS)

The concept of a solar-cell array for a solar power satellite is developed to permit evaluation of its economic feasibility for generating power for delivery to public utilities on earth. Gallium arsenide solar cells were considered but it could not be assured that the world gallium resources could support constructions of two solar power satellites per year. Therefore, for preliminary design an array blanket made from 5 by 10 cm silicon solar cells, 50 microns thick, and electrostatically bonded between borosilicate glass sheets was adopted. In annealing experiments, a radiated 50 microns thick cell was restored to its initial performance in a 500 C. Solar-cell efficiency effects significantly the solar power satellite mass, which varies from 90,000 metric tons for 20 percent cells to 120,000 metric tons for 12 percent cells. The anticipated cost of delivered power, based on 1977 dollars, varies from 4 cents per kWh with 18 percent cells, to 5 cents per kWh for 12 percent efficient cells.

Oman, H.

1978-01-01

40

All Electrochemical Layer Deposition for Crystalline Silicon Solar Cell Manufacturing: Experiments and Interpretation  

Microsoft Academic Search

A manufacturing process for crystalline silicon solar cells is presented which consists mainly of electrochemical steps. The deposition of doping glass layers for the front side emitter as well as the back surface field is performed anodically onto the etched and cleaned wafers. The doping atoms, phosphorus or boron, are diffused into the silicon crystal in a furnace at 950

F. Kröner; Z. Kröner; K. Reichmann; M. Rommel

41

The ATS-5 solar cell experiment after 6-1/2 years in synchronous orbit  

NASA Technical Reports Server (NTRS)

Several types of solar cell/coverslide combinations were launched into synchronous orbit. The cells were 2 and 10 ohm-cm crucible-grown silicon with thicknesses of 0.2 and 0.3 mm. Coverslides were fused silica, ranging in thickness from 0.15 to 1.52 mm. The cells were mounted on two panels, one a rigid aluminum honeycomb structure, giving essentially infinite backshielding; the other was a thin Kapton-fiberglass substrate, offering minimal protection to the rear surface of the cells. The current-voltage curves of the cells were measured. Correction of cell electrical output to standard temperature and solar intensity was performed, using empirical radiation-dependent corrections. It is found that the cells on the flexible panel degrade much more rapidly than predicted, while the rigid panel cells follow the predictions fairly well. The anomalous behavior of the flexible panel cells is attributed to the deposition of a contaminant on the cell coverslides.

Anspaugh, B.

1976-01-01

42

High efficiency silicon solar cells  

Microsoft Academic Search

During carrying out a project on high efficiency crystalline silicon solar cells, different materials (CZ and FZ wafers with different resistivities) and different structures were experimented upon. For improving solar cell performance, the technology of emitter passivation, AR surface texture and coating, HCl cleaning of the quartz tube, etc., were used. The best efficiency obtained to date is 18.2%

Zhao Yuwen; Li Zhongming; Mo Chundong; Lu Kun; Li Zhiming

1994-01-01

43

Solar Reformer Experiment Design Study.  

National Technical Information Service (NTIS)

This report describes the design of an experiment in which solar energy is provided to a steam-hydrocarbon reforming reactor placed inside a solar central receiver. The hardware design, process, operation options with the possible critical issues are anal...

T. Rozenman

1986-01-01

44

Polymer solar cells  

Microsoft Academic Search

Recent progress in the development of polymer solar cells has improved power-conversion efficiencies from 3% to almost 9%. Based on semiconducting polymers, these solar cells are fabricated from solution-processing techniques and have unique prospects for achieving low-cost solar energy harvesting, owing to their material and manufacturing advantages. The potential applications of polymer solar cells are broad, ranging from flexible solar

Gang Li; Rui Zhu; Yang Yang

2012-01-01

45

Flexible Solar Cells.  

National Technical Information Service (NTIS)

Solar cell 'modules' are plastic strips coated with thin films of photovoltaic silicon that collect solar energy for instant conversion into electricity. Lasers divide the thin film coating into smaller cells to build up voltage. Developed by Iowa Thin Fi...

1994-01-01

46

Indium phosphide solar cells  

NASA Technical Reports Server (NTRS)

The direction for InP solar cell research; reduction of cell cost; increase of cell efficiency; measurements needed to better understand cell performance; n/p versus p/n; radiation effects; major problems in cell contacting; and whether the present level of InP solar cell research in the USA should be maintained, decreased, or increased were considered.

Weinberg, Irving

1991-01-01

47

Solar Photovoltaic Cells.  

ERIC Educational Resources Information Center

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…

Mickey, Charles D.

1981-01-01

48

Experimenting with Solar Energy  

ERIC Educational Resources Information Center

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…

Roman, Harry T.

2004-01-01

49

Viking solar corona experiment  

Microsoft Academic Search

The 1976 Mars solar conjunction resulted in complete occulations of the Viking spacecraft by the sun at solar minimum. During the conjunction period, coherent 3.5- and 13-cm wavelength radio waves from the orbiters passed through the solar corona and were received with the 64-m antennas of the NASA Deep Space Network. Data were obtained within at least 0.3 and 0.8

G. LEONARD Tyler; Joseph P. Brenkle; Thomas A. Komarek; Arthur I. Zygielbaum

1977-01-01

50

Uniform solar cells  

NASA Technical Reports Server (NTRS)

Solar cells used in radiation sensors can be efficiently matched by individual trimming. Strip of aluminized Mylar is used to adjust cell output to within required tolerances. Method is faster than individual selection of matched cells.

1976-01-01

51

Fundamentals of solar cells  

Microsoft Academic Search

This text is addressed to upper level graduate students with background in solid state physics and to scientists and engineers involved in solar cell research. The author aims to present fundamental physical principles rather than the state-of-the-art. Specific devices are used to illustrate basic phenomena and to indicate possibilities for innovative design. Contents, abridged: Solar insolation. The calculation of solar

A. L. Farhenbruch; R. H. Bube

1983-01-01

52

Sub-bandgap absorption in organic solar cells: experiment and theory.  

PubMed

Most high-performance organic solar cells involve bulk-heterojunctions in order to increase the active donor-acceptor interface area. The power conversion efficiency depends critically on the nano-morphology of the blend and the interface. Spectroscopy of the sub-bandgap region, i.e., below the bulk absorption of the individual components, provides unique opportunities to study interface-related properties. We present absorption measurements in the sub-bandgap region of bulk heterojunctions made of poly(3-hexylthiophene-2,5-diyl) as an electron donor and [6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PCBM) as an electron acceptor and compare them with quantum-chemical calculations and recently published data on the external quantum efficiency (EQE). The very weak absorption of the deep sub-bandgap region measured by the ultra-sensitive Photothermal Deflection Spectroscopy (PDS) features Urbach tails, polaronic transitions, conventional excitons, and possibly charge-transfer states. The quantum-chemical calculations allow characterizing some of the unsettled spectral features. PMID:23929440

Beenken, Wichard J D; Herrmann, Felix; Presselt, Martin; Hoppe, Harald; Shokhovets, Sviatoslav; Gobsch, Gerhard; Runge, Erich

2013-10-21

53

First principles modeling of donor materials for organic solar cells: where theory complements experiment  

NASA Astrophysics Data System (ADS)

We discuss the predictive power and accuracy of first principles modeling of small-molecule crystalline donors for organic solar cells. First of all, in order to understand where the theory can help us in improving the performance of photovoltaic devices, we clarify what factors constituting power conversion efficiency needed to be improved. We argue these are short circuit current and fill factor, rather than bandgap and open circuit voltage. This implies that the optimization of intramolecular properties (e.g. HOMO/LUMO), which is best suitable for theoretical search, will not give the anticipated gain in efficiency. The intermolecular properties are amenable to first principles modeling on a single-crystallite scale and we discuss some challenges in this avenue. As an example of how theory can provide design rules for architecturing small-molecule crystals we analyze the dependence of charge carrier mobility on the intermolecular geometry of a pi-stack. In the other case study we show that changes in device performance due to small changes in chemical composition can be well tracked by the theory. Finally, we analyze the performance of commonly used density functionals for typical molecular systems used in organic electronics (oligomers, polymers, dimers, crystals).

Zhugayevych, Andriy; Tretiak, Sergei; Bazan, Guillermo

2013-03-01

54

Solar Cells and Photovoltaics  

Microsoft Academic Search

Photovoltaic solar cells are gaining wide acceptance for producing clean, renewable electricity. This has been based on more than 40 years of research that has benefited from the revolution in silicon electronics and compound semiconductors in optoelectronics. This chapter gives an introduction into the basic science of photovoltaic solar cells and the challenge of extracting the maximum amount of electrical

Stuart Irvine

2007-01-01

55

Heterostructure solar cells  

NASA Technical Reports Server (NTRS)

The performance of gallium arsenide solar cells grown on Ge substrates is discussed. In some cases the substrate was thinned to reduce overall cell weight with good ruggedness. The conversion efficiency of 2 by 2 cm cells under AMO reached 17.1 percent with a cell thickness of 6 mils. The work described forms the basis for future cascade cell structures, where similar interconnecting problems between the top cell and the bottom cell must be solved. Applications of the GaAs/Ge solar cell in space and the expected payoffs are discussed.

Chang, K. I.; Yeh, Y. C. M.; Iles, P. A.; Morris, R. K.

1987-01-01

56

Solar mesosphere explorer: Experiment description  

NASA Technical Reports Server (NTRS)

The Solar Mesosphere Explorer (SME) satellite experiments will provide a comprehensive study of atmospheric ozone and the processes which form and destroy it. Five instruments to be carried on the spacecraft will measure the ozone density and altitude distribution, monitor the incoming solar radiation, and measure other atmospheric constituents which affect ozone. The investigative approach concept, methods and procedures, preflight studies, and orbits and mission lifetime are presented. Descriptions of the instruments are also presented.

1977-01-01

57

Solar cell and cell mount  

Microsoft Academic Search

A point contact solar device is described comprising: solar cell dice, each die comprising: a semiconductive layer in which are formed wells of p-conductivity type and n-conductivity type in an alternating pattern, the wells extending to a bottom surface of the semiconductive layer; an insulating layer formed on the bottom surface of the semiconductive layer and patterned to expose the

D. L. Peltzer; R. L. Bechtel; W. C. Ko; W. T. Liggett

1989-01-01

58

Amorphous silicon solar cells  

Microsoft Academic Search

Amorphous silicon solar cells have been fabricated in several different structures: heterojunctions, p-i-n junctions, and Schottky barrier devices. The procedures used in constructing the various solar cells are discussed, and their photovoltaic properties are compared. At present, the highest conversion efficiency (5.5 percent) has been obtained with a Schottky barrier cell, and this structure appears to offer the best promise

D. E. Carlson

1977-01-01

59

Home-made experiment of Dye-sensitized TiO2 Nanocrystalline Solar Cells and its education evaluation  

NASA Astrophysics Data System (ADS)

Dyes extracted from some natural fruits including anthocyanins absorb sunlight and effectively activate electrons of anthocyanins. Thus these activated electrons are conducted between TiO2 nanocrystals and form electric potential and current between two electrodes. The dyes can be gotten from the natural fruits, such as blackberries, raspberry, pomegranate seeds and bing cherries. This principle permits making a dye sensitized TiO2 nanocrystallines solar cell (DSSC). All required materials and tools for fabricating a home- made DSSC are easy to obtain around home. The procedures are perfect hands-on experiment as well as demonstration in K-12 schools or home settings. We have designed several protocols for fabricating DSSC and have successfully demonstrated in more than 100 activities with different level students. K-12 Students were able to build their own working DSSC's within 2-3 hours sessions and learned about alternative energy sources. These experiments can inspire students and general public about the modern technology in daily life. Low cost (low than US 3 in Taiwan)and safety are also ensured in our DSSC experiments.

Tai, M. F.; Shieh, M. C.; Chen, T. W.

2010-03-01

60

Dye Sensitized Solar Cells  

PubMed Central

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.

Wei, Di

2010-01-01

61

Dye sensitized solar cells.  

PubMed

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. PMID:20480003

Wei, Di

2010-01-01

62

Solar cell radiation handbook  

NASA Technical Reports Server (NTRS)

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.

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

1982-01-01

63

Quantum dot solar cells  

Microsoft Academic Search

Quantum dot (QD) solar cells have the potential to increase the maximum attainable thermodynamic conversion efficiency of solar photon conversion up to about 66% by utilizing hot photogenerated carriers to produce higher photovoltages or higher photocurrents. The former effect is based on miniband transport and collection of hot carriers in QD array photoelectrodes before they relax to the band edges

A. J Nozik

2002-01-01

64

Photovoltaic solar cell  

DOEpatents

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.

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

2013-11-26

65

Conjugated Polymer Solar Cells.  

National Technical Information Service (NTIS)

This report results from a contract tasking Moscow State University as follows: Conjugated polymers are promising materials for many photonics applications, in particular, for photovoltaic and solar cell devices. This project will study the possibility to...

D. Y. Paraschuk

2006-01-01

66

Photovoltaic Experiment Using Light from a Solar Simulator Lamp.  

ERIC Educational Resources Information Center

A photovoltaic cell experiment utilizing the convenience of a solar simulating type lamp is described. Insight into the solid state aspect of a solar cell is gained by the student in studying the characteristics, and deducing from them cell parameters and efficiency. (Author/CS)

Chow, R. H.

1980-01-01

67

Inside a Solar Cell  

NSDL National Science Digital Library

Based on a NOVA Online lesson, Teachers' Domain presents this interactive activity that provides reading material and animations to help students learn the basics of photovoltaic cells, including how a solar cell converts solar energy into electricity and the components of the unit (silicon layers, metal backing, antireflective coating, and metal conductor strips). On the site, visitors will also find a supplemental background essay, discussion questions, and standards alignment from Teachers' Domain.

2010-10-06

68

Solar array flight experiment/dynamic augmentation experiment  

NASA Technical Reports Server (NTRS)

This report presents the objectives, design, testing, and data analyses of the Solar Array Flight Experiment/Dynamic Augmentation Experiment (SAFE/DAE) that was tested aboard Shuttle in September 1984. The SAFE was a lightweight, flat-fold array that employed a thin polyimide film (Kapton) as a substrate for the solar cells. Extension/retraction, dynamics, electrical and thermal tests, were performed. Of particular interest is the dynamic behavior of such a large lightweight structure in space. Three techniques for measuring and analyzing this behavior were employed. The methodology for performing these tests, gathering data, and data analyses are presented. The report shows that the SAFE solar array technology is ready for application and that new methods are available to assess the dynamics of large structures in space.

Young, Leighton E.; Pack, Homer C., Jr.

1987-01-01

69

Nanocrystalline electrochemical solar cells  

Microsoft Academic Search

Standard solar cells exploit the physics of semiconductors in which the energy of absorbed photons excites charge-carrier pairs which are subsequently separated by the influence of a solid state junction to provide a photovoltage. In the nanocrystalline electrochemical cell, the optical absorber is a dye monolayer which after photo-excitation injects electrons into a semiconductor substrate, with charge neutrality being restored

A. J. McEvoy; M. Gratzel; H. Wittkopf; D. Jestell; J. Benemann

1994-01-01

70

Inside a Solar Cell  

NSDL National Science Digital Library

This set of six interactive slides showcases how a typical photovoltaic cell converts solar energy into electricity. Explore the components of a photovoltaic cell, including the silicon layers, metal backing, antireflective coating, and metal conductor strips. Using animations, investigate why the silicon layers are doped with phosphorous and boron, and how an electric field is used to generate electricity from sunlight.

Nova; Domain, Teachers'

71

Transparent solar cell module  

NASA Technical Reports Server (NTRS)

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.

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

1979-01-01

72

Welded solar cell interconnection  

SciTech Connect

The welding of solar cell interconnects has received increased attention in recent years. Welding is used routinely in Europe and is being investigated seriously by several solar array fabricators in the United States. Most of this welding has been made using parallel gap resistive heating. Hughes Aircraft Company has chosen to investigate ultrasonic welding as an alternate bonding method. The results of this work and the manner in which ultrasonic welding differs from parallel gap welding or soldering is herein summarized.

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

1982-09-01

73

Status of solar neutrino experiments  

SciTech Connect

A summary of the status of four solar neutrino experiments is presented. The Homestake {sup 37}Cl data are presented and the possible time dependence of the data is addressed. Data from 1040 days of operation of the Kamiokande II detector are presented next. The status of the {sup 71}Ga experiment in the Baksan Neutrino Observatory, which has operated for a short time, is discussed. The summary concludes with a discussion of the status of the Sudbury Neutrino Observatory, which has been under construction since the beginning of 1990. 7 refs., 6 figs.

Beier, E.W.; Davis, R. Jr.; Kim, S.B. (Pennsylvania Univ., Philadelphia, PA (USA). Dept. of Physics); Elliott, S.R. (Los Alamos National Lab., NM (USA)); Jelley, N. (Oxford Univ. (UK))

1990-01-01

74

Experimenting with photoelectrochemical cells in drinking straws: practical aids for learning about solar energy in school or at home  

NASA Astrophysics Data System (ADS)

Photoelectrochemical cells using dye-sensitized ZnO with a Cu2+/Fe2+/Fe3+ electrolyte can be easily made at home or in a school classroom with household chemicals and other readily available materials. The cells, which are made with wire housed within plastic drinking straws, have open-circuit voltages of 0.5-0.7 V and short-circuit currents of about 0.5-2.5 mA cm-2. Step-by-step instructions are provided on how to construct the photoelectrochemical cells, as are suggestions about how to use the cells to explore some concepts associated with utilizing solar energy.

Appleyard, S. J.

2008-05-01

75

Cadmium sulfide solar cells  

NASA Technical Reports Server (NTRS)

Development, fabrication and applications of CdS solar cells are reviewed in detail. The suitability of CdS cells for large solar panels and microcircuitry, and their low cost, are emphasized. Developments are reviewed by manufacturer-developer. Vapor phase deposition of thin-film solar cells, doping and co-evaporation, sputtering, chemical spray, and sintered layers are reviewed, in addition to spray deposition, monograin layer structures, and silk screening. Formation of junctions by electroplating, evaporation, brushing, CuCl dip, and chemiplating are discussed, along with counterelectrode fabrication, VPD film structures, the Cu2S barrier layer, and various photovoltaic effects (contact photovoltage, light intensity variation, optical enhancement), and various other CdS topics.

Stanley, A. G.

1975-01-01

76

Flexible dye solar cells  

Microsoft Academic Search

Strategies towards flexible solid state solar cells based on nanocrystalline titanium oxide and organic hole conductor were investigated. For the flexible cell geometry a metal foil was used as substrate and a semi-transparent gold layer as counter electrode which allows light transmission (back illumination). The device performance of solid state cells based on SnO2:F coated glass on the one hand

Nathalie Rossier-Iten; Toby B. Meyer; Jessica Krueger; Michael Graetzel

2004-01-01

77

Interdigitated back contact solar cells  

Microsoft Academic Search

The interdigitated back contact solar cell (IBC cell) was shown to possess a number of advantages for silicon solar cells, which operate at high concentration. A detailed discussion of the factors which need to be considered in the analysis of semiconducting devices which utilize heavily doped regions such as those which are found in solar cells in both the emitter

M. S. Lundstrom; R. J. Schwartz

1980-01-01

78

Solar cell radiation handbook  

NASA Technical Reports Server (NTRS)

A method is presented for predicting the degradation of a solar array in a space radiation environment. Solar cell technology which emphasizes the cell parameters that degrade in a radiation environment, is discussed along with the experimental techniques used in the evaluation of radiation effects. Other topics discussed include: theoretical aspects of radiation damage, methods for developing relative damage coefficients, nature of the space radiation environment, method of calculating equivalent fluence from electron and proton energy spectrums and relative damage coefficients, and comparison of flight data with estimated degradation.

Carter, J. R., Jr.; Tada, H. Y.

1973-01-01

79

Ion Implanted Silicon Solar Cells.  

National Technical Information Service (NTIS)

The theory of pn-junction silicon solar cells is thoroughly discussed including detailed deductions and calculations concerning the theoretical spectral response and the dark current in a solar cell with a back surface field. Ion implantation theory is re...

P. Balslev

1981-01-01

80

Flexible solar cells.  

PubMed

Thin-film flexible photovoltaics are paving the way to low-cost electricity. Organic, inorganic and organic-inorganic solar cells are deposited over flexible substrates by high-throughput (often roll-to-roll printing) technologies to afford lightweight, economic solar modules that can be integrated into, not installed on, various surfaces. Current conversion efficiencies under standard conditions are in the 3-15 % range, but in real applications the overall productivity is high. These new photovoltaic technologies are ready to provide cheap, clean electricity to the 2 billion people who lack access to the grid as well as to energy-eager companies and families in the developed world facing the increasing costs of electricity generated using fossil fuel resources. This Review focuses on recent achievements in the area of flexible solar cells, highlights the principles behind the main technologies, and discusses future challenges in this area. PMID:18979493

Pagliaro, Mario; Ciriminna, Rosaria; Palmisano, Giovanni

2008-01-01

81

Solar cell area considerations  

Microsoft Academic Search

The impact of extra current collection from beyond the apparent solar cell edge on photovoltaic conversion efficiency is discussed. A fixed-beam movable x-y translation stage laser scan system is shown which can quantitatively measure such effects, and two examples of output from the scanner are illustrated. The recommendation is made that care should be exercised when reporting the efficiency of

C. R. Osterwald; K. A. Emery

1983-01-01

82

NASA Facts, Solar Cells.  

ERIC Educational Resources Information Center

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…

National Aeronautics and Space Administration, Washington, DC.

83

Amorphous semiconductor solar cell  

DOEpatents

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

Dalal, Vikram L. (Newark, DE)

1981-01-01

84

Lateral superlattice solar cells.  

National Technical Information Service (NTIS)

A novel structure which comprises of a lateral superlattice as the active layer of a solar cell is proposed. If the alternating regions A and B of a lateral superlattice ABABAB. are chosen to have a Type-II band offset, it is shown that the performance of...

A. Mascarenhas Y. Zhang J. M. Millunchick R. D. Twesten E. D. Jones

1997-01-01

85

Cadmium telluride solar cells  

SciTech Connect

Cadmium telluride is the only II-VI compound that can readily be prepared in both n- and p-type forms. Since, in addition, its bandgap lies near the optimum for solar energy conversion, it is currently one of the leading contenders for thin film terrestrial solar energy conversion. CdTe based solar cells with an efficiency of greater than 10% have been prepared by a variety of techniques including homojunction formation, chemical vapor transport of CdS to form a CdS/CdTe junction, electron beam evaporation of indium-tin oxide to form an ITO/CdTe junction, by closespaced vapor transport of both CdS and CdTe to form a CdS/CdTe junction, and by sintered layer techniques resulting in an all thin film sintered layer cell. Cells with creditable efficiency have also been prepared by ordinary vacuum evaporation of a window material, by spray pyrolysis deposition of a window material, and by electrodeposition of thin layers. This paper surveys research on CdTe solar cells and indicates the significant materials and device parameters.

Bube, R.H.

1983-05-01

86

Advanced solar cell concepts1  

Microsoft Academic Search

In order to ensure the widespread use of solar photovoltaic technology for terrestrial applications, cost per unit watt must be significantly lower than 1$\\/Watt level. Material limitation of wafer based Si cell technology and efficiency limitation of thin-film solar cell technologies needs to overcome in order to achieve the above- mentioned cost goal. Thermodynamically solar cell efficiencies can be as

C. S. Solanki; G. Beaucarne

2007-01-01

87

Electronics Implementation of the Solar Neutron Experiment.  

National Technical Information Service (NTIS)

The report is a supplement to the Themis renewal proposal December 14, 1970 to project Themis-1969: Research proposal, 'variations in the earth's atmosphere produced by solar radiations.' It describes the electronics used in experiment 1, the solar neutro...

W. A. Millard G. M. Simnett R. S. White

1970-01-01

88

Solar PV- How A Solar Cell Works  

NSDL National Science Digital Library

The Advanced Technology Environmental and Energy Center (ATEEC) provides this document which will help instructors or anyone who would like to understand the basics of solar power and solar cells. Users must download this resource for viewing, which requires a free log-in. There is no cost to download the item.

Levander, Alejandro

2011-03-03

89

A miniature high voltage plasma interaction flight experiment - Project MINX. [for measuring solar cell array parasitic current drain  

NASA Technical Reports Server (NTRS)

A miniature high-voltage array was fabricated, incorporating the multi-junction edge illuminated (MJC) cell technique. The array consists of 32 2x2.2 cm MJCs, series connected, capable of 1600 V open circuit at 1 AMO and 1.2 mA short circuit. A solid state, high-voltage relay is connected across each 4-cell subgroup of the array. It was built to test plasma current drain on space systems using high voltage as might occur when a high-voltage solar array is operated from low to synchronous orbit.

Riley, T. J.; Triner, J. E.; Sater, B. L.; Cohen, D.; Somberg, H.

1974-01-01

90

Coating Processes Boost Performance of Solar Cells  

NASA Technical Reports Server (NTRS)

NASA currently has spacecraft orbiting Mercury (MESSENGER), imaging the asteroid Vesta (Dawn), roaming the red plains of Mars (the Opportunity rover), and providing a laboratory for humans to advance scientific research in space (the International Space Station, or ISS). The heart of the technology that powers those missions and many others can be held in the palm of your hand - the solar cell. Solar, or photovoltaic (PV), cells are what make up the panels and arrays that draw on the Sun s light to generate electricity for everything from the Hubble Space Telescope s imaging equipment to the life support systems for the ISS. To enable NASA spacecraft to utilize the Sun s energy for exploring destinations as distant as Jupiter, the Agency has invested significant research into improving solar cell design and efficiency. Glenn Research Center has been a national leader in advancing PV technology. The Center s Photovoltaic and Power Technologies Branch has conducted numerous experiments aimed at developing lighter, more efficient solar cells that are less expensive to manufacture. Initiatives like the Forward Technology Solar Cell Experiments I and II in which PV cells developed by NASA and private industry were mounted outside the ISS have tested how various solar technologies perform in the harsh conditions of space. While NASA seeks to improve solar cells for space applications, the results are returning to Earth to benefit the solar energy industry.

2012-01-01

91

Flexible dye solar cells  

NASA Astrophysics Data System (ADS)

Strategies towards flexible solid state solar cells based on nanocrystalline titanium oxide and organic hole conductor were investigated. For the flexible cell geometry a metal foil was used as substrate and a semi-transparent gold layer as counter electrode which allows light transmission (back illumination). The device performance of solid state cells based on SnO2:F coated glass on the one hand and a metal foil on the other hand were characterized and compared by measuring the current voltage curves on back and front illumination.

Rossier-Iten, Nathalie; Meyer, Toby B.; Krueger, Jessica; Graetzel, Michael

2004-02-01

92

Very high efficiency solar cells  

NASA Astrophysics Data System (ADS)

The Defense Advanced Research Projects Agency has initiated the Very High Efficiency Solar Cell (VHESC) program to address the critical need of the soldier for power in the field. Very High Efficiency Solar Cells for portable applications that operate at greater than 55 percent efficiency in the laboratory and 50 percent in production are being developed. We are integrating the optical design with the solar cell design, and have entered previously unoccupied design space that leads to a new architecture paradigm. An integrated team effort is now underway that requires us to invent, develop and transfer to production these new solar cells. Our approach is driven by proven quantitative models for the solar cell design, the optical design and the integration of these designs. We start with a very high performance crystalline silicon solar cell platform. Examples will be presented. Initial solar cell device results are shown for devices fabricated in geometries designed for this VHESC Program.

Barnett, Allen; Kirkpatrick, Douglas; Honsberg, Christiana

2006-09-01

93

TROPIX: A solar electric propulsion flight experiment  

Microsoft Academic Search

The Transfer Orbit Plasma Interaction Experiment (TROPIX) is a proposed scientific experiment and flight demonstration of a solar electric propulsion vehicle. Its mission goals are to significantly increase our knowledge of Earth's magnetosphere and its associated plasma environment and to demonstrate an operational solar electric upper stage (SEUS) for small launch vehicles. The scientific investigations and flight demonstration technology experiments

J. Mark Hickman; G. Barry Hillard; Steven R. Oleson

1993-01-01

94

EDITORIAL: Nanostructured solar cells Nanostructured solar cells  

NASA Astrophysics Data System (ADS)

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 surfaces and interfaces, which are often the limiting factor in device performance. This issue provides concrete examples of how the techniques of nanoscience and nanotechnology can be used to understand, control and optimize the performance of novel photovoltaic devices. We are grateful to the contributors for submitting high-quality papers around a common theme, even though they may not normally consider their work to fall under the banner of 'nanotechnology'. We would also like to thank the editorial and production staff at Nanotechnology for their efficient and speedy work in putting this issue together.

Greenham, Neil C.; Grätzel, Michael

2008-10-01

95

Advances in solar cell technology  

Microsoft Academic Search

The advances in solar cell efficiency, radiation tolerance, and cost over the last decade are reviewed. Potential performance of thin-film solar cells in space are discussed, and the cost and the historical trends in production capability of the photovoltaics industry considered with respect to the requirements of satellite solar power systems.

Geoffrey A. Landis; Sheila G. Bailey

1995-01-01

96

Quantum Dot Solar Cells  

NASA Technical Reports Server (NTRS)

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.

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

2002-01-01

97

Solar cell radiation handbook. Addendum 1: 1982-1988  

NASA Technical Reports Server (NTRS)

The Solar Cell Radiation Handbook (JPL Publication 82-69) is updated. In order to maintain currency of solar cell radiation data, recent solar cell designs have been acquired, irradiated with 1 MeV electrons, and measured. The results of these radiation experiments are reported.

Anspaugh, Bruce E.

1989-01-01

98

Compound polycrystalline solar cells  

Microsoft Academic Search

A historical perspective on the development of polycrystalline thin-film solar cells based on CdTe and CuInSe2 is presented, and recent progress of these thin-film technologies is discussed. Impressive improvements in the efficiency of laboratory scale devices has not been easy to translate to the manufacturing environment, principally due to our lack of understanding of the basic science and engineering of

Robert W. Birkmire

2001-01-01

99

Solar-cell  

SciTech Connect

A solar cell having a rear side contact and a conduction path system as front side contact. The gist of the invention is that a region of the second conductivity type is disposed on all sides of a semiconductor member of the first conductivity type, and that the rear side contact ohmically contacts the semiconductor member of the first conductivity type by penetrating the region of the second conductivity type.

Rasch, K.-D.; Flodl, H.

1985-09-24

100

Quantum Dot Solar Cells  

Microsoft Academic Search

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

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

2002-01-01

101

Silicon Solar Cell Turns 50  

SciTech Connect

This short brochure describes a milestone in solar (or photovoltaic, PV) research-namely, the 50th anniversary of the invention of the first viable silicon solar cell by three researchers at Bell Laboratories.

Perlin, J.

2004-08-01

102

Solar cells - A technology assessment  

Microsoft Academic Search

A qualitative assessment is made of the state-of-the-art in solar cell development and materials, together with projections of areas of future progress. The benefits and deficiencies of solar cells are surveyed, including the passive, low maintenance qualities of solar cell panels, the necessity of having a back-up system at night, and the low power conversion efficiencies available from current cells,

J. R. Bolton

1983-01-01

103

Laser-assisted solar cell metallization processing  

NASA Technical Reports Server (NTRS)

Laser assisted processing techniques utilized to produce the fine line, thin metal grid structures that are required to fabricate high efficiency solar cells are investigated. The tasks comprising these investigations are summarized. Metal deposition experiments are carried out utilizing laser assisted pyrolysis of a variety of metal bearing polymer films and metalloorganic inks spun onto silicon substrates. Laser decomposition of spun on silver neodecanoate ink yields very promising results. Solar cell comb metallization patterns are written using this technique.

Dutta, S.

1984-01-01

104

Epitaxial solar cells fabrication  

NASA Technical Reports Server (NTRS)

Silicon epitaxy has been studied for the fabrication of solar cell structures, with the intent of optimizing efficiency while maintaining suitability for space applications. SiH2CL2 yielded good quality layers and junctions with reproducible impurity profiles. Diode characteristics and lifetimes in the epitaxial layers were investigated as a function of epitaxial growth conditions and doping profile, as was the effect of substrates and epitaxial post-gettering on lifetime. The pyrolytic decomposition of SiH4 was also used in the epitaxial formation of highly doped junction layers on bulk Si wafers. The effects of junction layer thickness and bulk background doping level on cell performance, in particular, open-circuit voltage, were investigated. The most successful solar cells were fabricated with SiH2 CL2 to grow p/n layers on n(+) substrates. The best performance was obtained from a p(+)/p/n/n(+) structure grown with an exponential grade in the n-base layer.

Daiello, R. V.; Robinson, P. H.; Kressel, H.

1975-01-01

105

Quantum junction solar cells.  

PubMed

Colloidal quantum dot solids combine convenient solution-processing with quantum size effect tuning, offering avenues to high-efficiency multijunction cells based on a single materials synthesis and processing platform. The highest-performing colloidal quantum dot rectifying devices reported to date have relied on a junction between a quantum-tuned absorber and a bulk material (e.g., TiO(2)); however, quantum tuning of the absorber then requires complete redesign of the bulk acceptor, compromising the benefits of facile quantum tuning. Here we report rectifying junctions constructed entirely using inherently band-aligned quantum-tuned materials. Realizing these quantum junction diodes relied upon the creation of an n-type quantum dot solid having a clean bandgap. We combine stable, chemically compatible, high-performance n-type and p-type materials to create the first quantum junction solar cells. We present a family of photovoltaic devices having widely tuned bandgaps of 0.6-1.6 eV that excel where conventional quantum-to-bulk devices fail to perform. Devices having optimal single-junction bandgaps exhibit certified AM1.5 solar power conversion efficiencies of 5.4%. Control over doping in quantum solids, and the successful integration of these materials to form stable quantum junctions, offers a powerful new degree of freedom to colloidal quantum dot optoelectronics. PMID:22881834

Tang, Jiang; Liu, Huan; Zhitomirsky, David; Hoogland, Sjoerd; Wang, Xihua; Furukawa, Melissa; Levina, Larissa; Sargent, Edward H

2012-09-12

106

Schottky barrier solar cell  

NASA Astrophysics Data System (ADS)

A method of fabricating a Schottky barrier solar cell is described. The cell consists of a thin substrate of low cost material with at least the top surface of the substrate being electrically conductive. A thin layer of heavily doped n-type polycrystalling germanium is deposited on the substrate after a passivation layer is deposited to prevent migration of impurities into the polycrystalline germanium. The polycrystalline germanium is recrystallized to increase the crystal sizes to serve as a base layer on which a thin layer of gallium arsenide is vapor-epitaxilly grown followed by a thermally-grown oxide layer. A metal layer is deposited on the oxide layer and a grid electrode is deposited to be in electrical contact with the top surface of the metal layer.

Stirn, R. J.; Yeh, Y. C. M.

1981-07-01

107

Schottky barrier solar cell  

NASA Technical Reports Server (NTRS)

A method of fabricating a Schottky barrier solar cell is described. The cell consists of a thin substrate of low cost material with at least the top surface of the substrate being electrically conductive. A thin layer of heavily doped n-type polycrystalling germanium is deposited on the substrate after a passivation layer is deposited to prevent migration of impurities into the polycrystalline germanium. The polycrystalline germanium is recrystallized to increase the crystal sizes to serve as a base layer on which a thin layer of gallium arsenide is vapor-epitaxilly grown followed by a thermally-grown oxide layer. A metal layer is deposited on the oxide layer and a grid electrode is deposited to be in electrical contact with the top surface of the metal layer.

Stirn, R. J.; Yeh, Y. C. M. (inventors)

1981-01-01

108

Solar Molten Salt Electric Experiment.  

National Technical Information Service (NTIS)

Second generation solar power tower technology, based on using a molten nitrate salt as the solar receiver and thermal storage heat transfer fluid, is now in the final phase of preoperational testing at the Central Receiver Test Facility (CRTF) near Albuq...

J. T. Holmes

1983-01-01

109

Solar chimneys: simulation and experiment  

Microsoft Academic Search

The use of solar chimneys in buildings is one way to increment natural ventilation and, as a consequence, to improve indoor air quality. They are similar to conventional chimneys except that the south wall is replaced by a glazing. In order to compare the behaviour of a solar chimney with a conventional one, one of each was built in Porto.

Clito Afonso; Armando Oliveira

2000-01-01

110

EDITORIAL: Nanostructured solar cells Nanostructured solar cells  

Microsoft Academic Search

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

Neil C. Greenham; Michael Grätzel

2008-01-01

111

Carbon Nanotube Solar Cells  

PubMed Central

We present proof-of-concept all-carbon solar cells. They are made of a photoactive side of predominantly semiconducting nanotubes for photoconversion and a counter electrode made of a natural mixture of carbon nanotubes or graphite, connected by a liquid electrolyte through a redox reaction. The cells do not require rare source materials such as In or Pt, nor high-grade semiconductor processing equipment, do not rely on dye for photoconversion and therefore do not bleach, and are easy to fabricate using a spray-paint technique. We observe that cells with a lower concentration of carbon nanotubes on the active semiconducting electrode perform better than cells with a higher concentration of nanotubes. This effect is contrary to the expectation that a larger number of nanotubes would lead to more photoconversion and therefore more power generation. We attribute this to the presence of metallic nanotubes that provide a short for photo-excited electrons, bypassing the load. We demonstrate optimization strategies that improve cell efficiency by orders of magnitude. Once it is possible to make semiconducting-only carbon nanotube films, that may provide the greatest efficiency improvement.

Klinger, Colin; Patel, Yogeshwari; Postma, Henk W. Ch.

2012-01-01

112

SPDE: Solar Plasma Diagnostic Experiment  

NASA Technical Reports Server (NTRS)

The physics of the Solar corona is studied through the use of high resolution soft x-ray spectroscopy and high resolution ultraviolet imagery. The investigation includes the development and application of a flight instrument, first flown in May, 1992 on NASA sounding rocket 36.048. A second flight, NASA founding rocket 36.123, took place on 25 April 1994. Both flights were successful in recording new observations relevant to the investigation. The effort in this contract covers completion of the modifications to the existing rocket payload, its reflight, and the preliminary day reduction and analysis. Experience gained from flight 36.048 led us to plan several payload design modifications. These were made to improve the sensitivity balance between the UV and EUV spectrographs, to improve the scattered light rejection in the spectrographs, to protect the visible light rejection filter for the Normal Incidence X-ray Imager instrument (NIXI), and to prepare one new multilayer mirror coating to the NIXI. We also investigated the addition of a brassboard CCD camera to the payload to test it as a possible replacement for the Eastman type 101-07 film used by the SPDE instruments. This camera was included in the experimeter's data package for the Project Initiation Conference for the flight of NASA Mission 36.123, held in January, 1994, but for programmatic reasons was deleted from the final payload configuration. The payload was shipped to the White Sands Missile Range on schedule in early April. The launch and successful recovery took place on 25 April, in coordination with the Yohkoh satellite and a supporting ground-based observing campaign.

Bruner, Marilyn E.

1995-01-01

113

GaAs Solar Cell Radiation Handbook  

NASA Technical Reports Server (NTRS)

History of GaAs solar cell development is provided. Photovoltaic equations are described along with instrumentation techniques for measuring solar cells. Radiation effects in solar cells, electrical performance, and spacecraft flight data for solar cells are discussed. The space radiation environment and solar array degradation calculations are addressed.

Anspaugh, B. E.

1996-01-01

114

Inversion layer MOS solar cells  

NASA Technical Reports Server (NTRS)

Inversion layer (IL) Metal Oxide Semiconductor (MOS) solar cells were fabricated. The fabrication technique and problems are discussed. A plan for modeling IL cells is presented. Future work in this area is addressed.

Ho, Fat Duen

1986-01-01

115

Supramolecular solar cells  

NASA Astrophysics Data System (ADS)

Supramolecular chemistry - chemistry of non-covalent bonds including different type of intermolecular interactions viz., ion-pairing, ion-dipole, dipole-dipole, hydrogen bonding, cation-pi and Van der Waals forces. Applications based on supramolecular concepts for developing catalysts, molecular wires, rectifiers, photochemical sensors have been evolved during recent years. Mimicking natural photosynthesis to build energy harvesting devices has become important for generating energy and solar fuels that could be stored for future use. In this dissertation, supramolecular chemistry is being explored for creating light energy harvesting devices. Photosensitization of semiconductor metal oxide nanoparticles, such as titanium dioxide (TiO2) and tin oxide (SnO2,), via host-guest binding approach has been explored. In the first part, self-assembly of different porphyrin macrocyclic compounds on TiO2 layer using axial coordination approach is explored. Supramolecular dye sensitized solar cells built based on this approach exhibited Incident Photon Conversion Efficiency (IPCE) of 36% for a porphyrin-ferrocene dyad. In the second part, surface modification of SnO2 with water soluble porphyrins and phthalocyanine resulted in successful self-assembly of dimers on SnO2 surface. IPCE more than 50% from 400 - 700 nm is achieved for the supramolecular self-assembled heterodimer photocells is achieved. In summary, the axial ligation and ion-pairing method used as supramolecular tools to build photocells, exhibited highest quantum efficiency of light energy conversion with panchromatic spectral coverage. The reported findings could be applied to create interacting molecular systems for next generation of efficient solar energy harvesting devices.

Subbaiyan, Navaneetha Krishnan

116

A solar cell characteristics plotter  

NASA Astrophysics Data System (ADS)

This paper describes a solar-cell characteristics plotter with its associated sample holder. The plotter has facilities for both manual and auto-plotting, with built-in current limit against damage of the solar cell under test. Either current or power output can be plotted as a function of terminal voltage, and there is provision for marking the maximum power point on the curve. The sample holder allows the temperature of the solar cell to be varied over a range from approximately -188 to 250 C and permits investigation of other properties of materials used in the making of the solar cell, e.g. the antireflection layer. If temperature variation is not required the holder can be water cooled to prevent overheating of the solar cell during test. The plotter can also be used for the investigation of other semiconductor devices, and is ideal for use in small research and development laboratories.

Lam, Y. W.

1981-11-01

117

The small community solar thermal power experiment  

NASA Technical Reports Server (NTRS)

the objectives and current status of the Small Community Solar Thermal Power Experiment are discussed. The adjustments in programs goals made in response to the changing emphasis in the area of solar energy in national policy are addressed. Planned fabrication and testing activities for the test bed concentrator, power conversion assembly, and control system are outlined.

Kiceniuk, T.

1982-01-01

118

Russian-American Gallium solar neutrino Experiment.  

National Technical Information Service (NTIS)

The Russian-American Gallium solar neutrino Experiment (SAGE) is described. The solar neutrino flux measured by 31 extractions through October, 1993 is presented. The result of 69 (+-) (10 to the -7th power) to the 5th power SNU is to be compared with a s...

S. R. Elliott J. N. Abdurashitov T. J. Bowles

1995-01-01

119

The GALLEX solar neutrino experiment  

SciTech Connect

The recently published GALLEX result, 83 [plus minus] 19 (stat.) [plus minus]8 (syst.) SNU (10[sigma]), was obtained from data accumulated from 14 solar runs (with counting done to May, 1992). This value, while 2 standard deviations below the predictions of solar models, provided the first direct evidence for solar pp neutrinos. The signature for neutrino capture in the aqueous gallium-chloride detector was the observation of the characteristic energy spectrum (K and L X rays/Auger electrons), decaying with the half-life of the chemically isolated radioactive product, [sup 71]Ge. By adding to the data set 1 more solar run plus 4 additional months of counting (to September, 1992), an updated value of the GALLEX production rate was obtained, which, interestingly, does not differ perceptibly from our published value.

Hahn, R.L.

1992-01-01

120

High-efficiency silicon space solar cells  

Microsoft Academic Search

SHARP's activities on Si solar cells developments and features of Si solar cells for space use in comparison with GaAs solar cells are presented. Two types of high-efficiency silicon solar cells and the same kinds of high-efficiency solar cells with integrated bypass function (IBF cells) were developed and qualified for space applications. The NRS\\/LBSF cells and NRS\\/BSF cells showed an

Akio Suzuki

1998-01-01

121

Upconversion in solar cells  

PubMed Central

The possibility to tune chemical and physical properties in nanosized materials has a strong impact on a variety of technologies, including photovoltaics. One of the prominent research areas of nanomaterials for photovoltaics involves spectral conversion. Modification of the spectrum requires down- and/or upconversion or downshifting of the spectrum, meaning that the energy of photons is modified to either lower (down) or higher (up) energy. Nanostructures such as quantum dots, luminescent dye molecules, and lanthanide-doped glasses are capable of absorbing photons at a certain wavelength and emitting photons at a different (shorter or longer) wavelength. We will discuss upconversion by lanthanide compounds in various host materials and will further demonstrate upconversion to work for thin-film silicon solar cells.

2013-01-01

122

Back wall solar cell  

NASA Technical Reports Server (NTRS)

A solar cell is disclosed which comprises a first semiconductor material of one conductivity type with one face having the same conductivity type but more heavily doped to form a field region arranged to receive the radiant energy to be converted to electrical energy, and a layer of a second semiconductor material, preferably highly doped, of opposite conductivity type on the first semiconductor material adjacent the first semiconductor material at an interface remote from the heavily doped field region. Instead of the opposite conductivity layer, a metallic Schottky diode layer may be used, in which case no additional back contact is needed. A contact such as a gridded contact, previous to the radiant energy may be applied to the heavily doped field region of the more heavily doped, same conductivity material for its contact.

Brandhorst, H. W., Jr. (inventor)

1978-01-01

123

Multiple Exciton Generation Solar Cells  

SciTech Connect

Heat loss is the major factor limiting traditional single junction solar cells to a theoretical efficiency of 32%. Multiple Exciton Generation (MEG) enables efficient use of the solar spectrum yielding a theoretical power conversion efficiency of 44% in solar cells under 1-sun conditions. Quantum-confined semiconductors have demonstrated the ability to generate multiple carriers but present-day materials deliver efficiencies far below the SQ limit of 32%. Semiconductor quantum dots of PbSe and PbS provide an active testbed for developing high-efficiency, inexpensive solar cells benefitting from quantum confinement effects. Here, we will present recent work of solar cells employing MEG to yield external quantum efficiencies exceeding 100%.

Luther, J. M.; Semonin, O. E.; Beard, M. C.; Gao, J.; Nozik, A. J.

2012-01-01

124

Solar models, neutrino experiments, and helioseismology  

NASA Technical Reports Server (NTRS)

The event rates and their recognized uncertainties are calculated for 11 solar neutrino experiments using accurate solar models. These models are also used to evaluate the frequency spectrum of the p and g oscillations modes of the sun. It is shown that the discrepancy between the predicted and observed event rates in the Cl-37 and Kamiokande II experiments cannot be explained by a 'likely' fluctuation in input parameters with the best estimates and uncertainties given in the present study. It is suggested that, whatever the correct solution to the solar neutrino problem, it is unlikely to be a 'trival' error.

Bahcall, John N.; Ulrich, Roger K.

1988-01-01

125

High voltage solar array experiments  

NASA Technical Reports Server (NTRS)

The interaction between the components of a high voltage solar array and a simulated space plasma is studied to obtain data for the design of a high voltage solar array capable of 15kW at 2 to 16kV. Testing was conducted in a vacuum chamber 1.5-m long by 1.5-m diameter having a plasma source which simulated the plasma conditions existing in earth orbit between 400 nautical miles and synchronous altitude. Test samples included solar array segments pinholes in insulation covering high voltage electrodes, and plain dielectric samples. Quantitative data are presented in the areas of plasma power losses, plasma and high voltage induced damage, and dielectric properties. Limitations of the investigation are described.

Kennerud, K. L.

1974-01-01

126

Report on solar neutrino experiments  

SciTech Connect

A summary is given of the status of solar neutrino research that includes results of the Brookhaven chlorine detector, a discussion of the development of the gallium, bromine, and lithium radiochemical detectors. The gallium and bromine radiochemical detectors are developed and are capable of giving critical information of interest about neutrino physics and the fusion reactions in the interior of the sun. A plan for building these detectors is outlined and a rough cost estimate is given. A review is given of the plans in the Soviet Union in solar neutrino research.

Davis, R. Jr.; Cleveland, B.T.; Rowley, J.K.

1984-11-15

127

Thin monocrystalline silicon solar cells  

Microsoft Academic Search

One of the most effective approaches for a cost reduction of crystalline silicon solar cells is the better utilization of the crystals by cutting thinner wafers. However, such thin silicon wafers must have sufficient mechanical strength to maintain a high mechanical yield in cell and module manufacturing. The electrical performance of thin cells drops strongly with decreasing cell thickness if

K. A. Muenzer; Konstantin T. Holdermann; Reinhold E. Schlosser; Steffen Sterk

1999-01-01

128

Photoelectrochemical solar cells  

SciTech Connect

The first part of the book gives a current introduction to photoelectrochemistry, discussing some of the outstanding achievements accomplished in recent years. A review of the physics of semiconductors and pn junctions includes the band model of semiconductors, the optical effects, surface states and insulators. This is followed by a chapter on techniques for the characterization of semiconductors, focussing on the characterization of the interface in photoelectrochemical cells using the dielectric properties. The second part of the book covers X-ray photoelectron spectroscopy, variability of conduction due to the extent of doping and techniques for thin film deposition. The spectral characterization of a semiconductor is also considered, using photoacoustic and photothermal spectroscopy. A review of molten salt electrolyte systems followed by the preparation of chemicals through photoelectrochemical solar cells brings the reader up to date on the latest progress in this field. The last part of the book covers the basic instrumentation required for the photoelectrochemical work and its application to band gap measurement.

Santhanam, K.S.V.; Sharon, M.

1988-01-01

129

Prospects of cascade solar cells  

Microsoft Academic Search

The level of technological development of cascade solar cells (CSS) is assessed. CSS comprise thin layers of semiconductor materials, each absorbant in a part of the solar spectrum and transparent to the rest. Lattice-matching is required between the absorbing layers and the substrates. Progress is still necessary in this area to reduce dislocations and increase the carrier lifetime. Work is

S. M. Bedair

1984-01-01

130

Evaluation of diffusion-recombination parameters in electrodeposited CuIn(S, Se) 2 solar cells by means of electron beam induced current experiments and modelling  

NASA Astrophysics Data System (ADS)

Thin-film solar cells with a Cu-based chalcopyrite absorber achieve high conversion efficiencies (up to 20%). Their technology being more cost effective than the crystalline silicon technologies, they are expected to replace Si-based solar cells. But a best cost-performance ratio requires first a knowledge of the parameters which ascertain the electrical quality of the solar cell. The first of them is the minority carrier diffusion length in the absorber and the second one is the collection efficiency of the p-n junction space charge region (SCR) located within the absorber. A low value of at least one of them drastically reduces the efficiency of the cell. In this paper we present an electron-beam-induced-current (EBIC) determination of these two parameters in CIS solar cells.

Sieber, B.; Ruiz, C. M.; Bermudez, V.

2009-04-01

131

The Viking solar corona experiment  

NASA Technical Reports Server (NTRS)

The 1976 Mars solar conjunction resulted in complete occultations of the Viking spacecraft by the sun at solar minimum. During the conjunction period, coherent 3.5- and 13-cm wavelength radio waves from the orbiters passed through the solar corona and were received with the 64-m antennas of the NASA Deep Space Network. Data were obtained within at least 0.3 and 0.8 R sub s of the photosphere at the 3.5- and 13-cm wavelengths, respectively. The data can be used to determine the plasma density integrated along the radio path, the velocity of density irregularities in the coronal plasma, and the spectrum of the density fluctuations in the plasma. Observations of integrated plasma density near the south pole of the sun generally agree with a model of the corona which has an 8:1 decrease in plasma density from the equator to the pole. Power spectra of the 3.5- and 13-cm signals at a heliocentric radial distance of about 2 R sub s have a 1/2 power width of several hundred hertz and vary sharply with proximate geometric miss distance. Spectral broadening indicates a marked progressive increase in plasma irregularities with decreasing ray altitude at scales between about 1 and 100 km.

Tyler, G. L.; Brenkle, J. P.; Komarek, T. A.; Zygielbaum, A. I.

1977-01-01

132

TROPIX: A SOLAR ELECTRIC PROPULSION FLIGHT EXPERIMENT  

Microsoft Academic Search

which was never flown and is still in storage. Since then, a variety of small station-keeping electric thrusters have The Transfer Orbit Plasma Interaction Experiment been developed and flown by the United States, the (TROPIX) is a proposed scientific experiment and flight United Kingdom, and the USSR. Research and develop- demonstration of a solar electric propulsion vehicle. Its ment have

J. Mark Hickman; G. Barry Hillard; Steven R. Olesont

133

Solar cell with back side contacts  

DOEpatents

A III-V solar cell is described herein that includes all back side contacts. Additionally, the positive and negative electrical contacts contact compoud semiconductor layers of the solar cell other than the absorbing layer of the solar cell. That is, the positive and negative electrical contacts contact passivating layers of the solar cell.

Nielson, Gregory N; Okandan, Murat; Cruz-Campa, Jose Luis; Resnick, Paul J; Wanlass, Mark Woodbury; Clews, Peggy J

2013-12-24

134

Dust removal from solar cells  

NASA Technical Reports Server (NTRS)

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."

Ashpis, David E. (Inventor)

2011-01-01

135

Solar Radiation and Climate Experiment (SORCE) Satellite  

NASA Technical Reports Server (NTRS)

This is a close-up of the NASA-sponsored Solar Radiation and Climate Experiment (SORCE) Satellite. The SORCE mission, launched aboard a Pegasus rocket January 25, 2003, will provide state of the art measurements of incoming x-ray, ultraviolet, visible, near-infrared, and total solar radiation. Critical to studies of the Sun and its effect on our Earth system and mankind, SORCE will provide measurements that specifically address long-term climate change, natural variability and enhanced climate prediction, and atmospheric ozone and UV-B radiation. Orbiting around the Earth accumulating solar data, SORCE measures the Sun's output with the use of state-of-the-art radiometers, spectrometers, photodiodes, detectors, and bolo meters engineered into instruments mounted on a satellite observatory. SORCE is carrying 4 instruments: The Total Irradiance Monitor (TIM); the Solar Stellar Irradiance Comparison Experiment (SOLSTICE); the Spectral Irradiance Monitor (SIM); and the XUV Photometer System (XPS).

2003-01-01

136

Solar Mass Ejection Imager (SMEI) space experiment  

Microsoft Academic Search

The Solar Mass Ejection Imager (SMEI) is a proof-of-concept space experiment designed to observe solar coronal mass ejections (CMEs) and forecast their arrival at Earth. SMEI will image CMEs by sensing sunlight scattered from the free electrons in these ejecta (i.e., Thomson scattering). SMEI will be launched by a Titan II rocket into a circular, 830-km, sun-synchronous orbit in mid-2002

Richard R. Radick

2001-01-01

137

Solar power tower development: Recent experiences  

SciTech Connect

Recent experiences with the 10 MW{sub e} Solar Two and the 2.5 MW{sub t} TSA (Technology Program Solar Air Receiver) demonstration plants are reported. The heat transfer fluids used in these solar power towers are molten-nitrate salt and atmospheric air, respectively. Lessons learned and suggested technology improvements for next-generation plants are categorized according to subsystem. The next steps to be taken in the commercialization process for each these new power plant technologies is also presented.

Tyner, C.; Kolb, G.; Prairie, M. [and others

1996-12-01

138

24% efficient silicon solar cells  

Microsoft Academic Search

This paper reports significant progress in silicon solar cell performance, taking confirmed efficiency beyond 24% for the first time. This progress has been achieved by a combination of several mechanisms. One is the reduction of recombination at the cell front surface by improved passivation of the silicon\\/silicon dioxide interface. Resistive losses in the cell have been reduced by a double-plating

Jianhua Zhao; Aihua Wang; Pietro P. Altermatt; Stuart R. Wenham; Marltin A. Green

1994-01-01

139

Radiation effects in solar cells  

NASA Astrophysics Data System (ADS)

Two types of space solar cells, silicon single-junction and InGaP/GaAs/Ge triple-junction (3J) solar cells, have been primarily adopted for spacecraft. The conversion efficiencies of the solar cells under AM0, 1 sun condition are ~17% for silicon and ~30% for 3J cells. Radiation degradation occurs in space due to high-energy electrons and protons existing in space environment. The degradation is caused by radiation induced crystal defects which act as minority-carrier recombination centers and majority-carrier trap centers. The 3J cells are superior radiation resistant to the silicon cells, and this is mainly because the InGaP top-subcell has property of very high radiation resistance.

Imaizumi, Mitsuru; Ohshima, Takeshi

2013-05-01

140

Space solar cells—tradeoff analysis  

Microsoft Academic Search

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

M. Raja Reddy

2003-01-01

141

Solar Array Module Plasma Interaction Experiment (SAMPIE): Technical requirements document  

NASA Technical Reports Server (NTRS)

The Solar Array Module Plasma Interactions Experiment (SAMPIE) is a NASA shuttle space flight experiment scheduled for launch in early 1994. The SAMPIE experiment will investigate plasma interactions of high voltage space power systems in low earth orbit. Solar cell modules, representing several technologies, will be biased to high voltages to characterize both arcing and plasma current collection. Other solar modules, specially modified in accordance with current theories of arcing and breakdown, will demonstrate the possibility of arc suppression. Finally, several test modules will be included to study the basic nature of these interactions. The science and technology goals for the project are defined in the Technical Requirements Document (TRD) which is presented here.

Hillard, G. Barry; Ferguson, Dale C.

1992-01-01

142

Gap/silicon Tandem Solar Cell with Extended Temperature Range  

NASA Technical Reports Server (NTRS)

A two-junction solar cell has a bottom solar cell junction of crystalline silicon, and a top solar cell junction of gallium phosphide. A three (or more) junction solar cell has bottom solar cell junctions of silicon, and a top solar cell junction of gallium phosphide. The resulting solar cells exhibit improved extended temperature operation.

Landis, Geoffrey A. (Inventor)

2006-01-01

143

Point contact silicon solar cells  

NASA Technical Reports Server (NTRS)

A new type of silicon solar cell has been developed. It is called the point-contact cell because the metal semiconductor contacts are restricted to an array of small points on the back of the cell. The point contact cell has recently demonstrated 22 percent conversion efficiency at one sun and 27.5 percent at 100 suns under an AM1.5 spectrum.

Swanson, Richard M.

1987-01-01

144

Sprayed cadmium sulphide solar cells  

NASA Astrophysics Data System (ADS)

A spray process for the production of thin-film (5 microns) Cd/Cu(x)S solar cells is discussed and typical results are presented for the resulting cells. Plans for long-term very-large-scale production of cadmium sulfide cells are examined together with projected cost data and basic design criteria. A schematic representation of the cell, spray process, and an I/V curve are given.

Roderick, G. A.

145

Lithium counterdoped silicon solar cell  

NASA Technical Reports Server (NTRS)

The resistance to radiation damage of an n(+)p boron doped silicon solar cell is improved by lithium counterdoping. Even though lithium is an n-dopant in silicon, the lithium is introduced in small enough quantities so that the cell base remains p-type. The lithium is introduced into the solar cell wafer by implantation of lithium ions whose energy is about 50 keV. After this lithium implantation, the wafer is annealed in a nitrogen atmosphere at 375 C for two hours.

Weinberg, I. (inventor); Brandhorst, H. W., Jr. (inventor)

1986-01-01

146

Low Cost Solar Cell Arrays.  

National Technical Information Service (NTIS)

Limitations in both space and terrestial markets for solar cells are described. Based on knowledge of the state-of-the-art, six cell options are discussed; as a result of this discussion, the three most promising options (involving high, medium and low ef...

P. A. Iles H. Mclennan

1975-01-01

147

Solar cell and array standardization for Air Force spacecraft  

NASA Astrophysics Data System (ADS)

Efforts have been in progress to evaluate and to accomplish solar cell and array standardization for Air Force spacecraft. Analysis results indicate that the array area and weight penalties that typically would be involved in the use of a standard solar cell module would be less than 10%. The potential payoff of standardization is cost savings to the Air Force and improved solar array reliability. Cost experience data from NASA are used to show that large savings over a 12-year period might be possible. An attempt is being made to standardize procurement practices at the power system and solar array levels and to standardize hardware at the solar cell level. Three documents have been prepared as part of this effort: a military standard for the design of space vehicles dc power systems (MIL-STD-1539), a military specification for solar arrays (MIL-S-XXXXX), and a military specification for solar cells (MIL-C-83443).

Killian, H. J.; Wade, E.; Wise, J. F.; Sampson, H. T.

1974-07-01

148

The Cassini solar Faraday rotation experiment  

Microsoft Academic Search

The Cassini Faraday rotation experiment improves the current understanding of the coronal magnetic field by making the first measurements of the magnetic field within two solar radii of the south pole and by allowing the separation of the changing electron density from the magnetic field during transient crossings of the line of sight. Simultaneous ranging data to Cassini also contributes

E. A. Jensen; M. K. Bird; S. W. Asmar; L. Iess; J. D. Anderson; C.T. Russell

2005-01-01

149

TIMED Solar EUV Experiment: Phase E  

NASA Technical Reports Server (NTRS)

The timed Solar EUV Experiment (SEE) Phase E Annual Report for 2002 is presented. The contents include: 1) SEE Science Overview; 2) SEE Instrument Overview and Status; 3) Summary of SEE Data Products; 4) Summary of SEE Results; 5) Summary of SEE Related Talks and Papers; and 6) Future Plans for SEE Team. This paper is in viewgraph form.

Woods, Tom; Eparvier, Frank; Woodraska, Don; Rottman, Gary; Solomon, Stan; Roble, Ray; deToma, Guliana; White, Dick; Lean, Judith; Tobiska, Kent; Bailey, Scott

2002-01-01

150

Evaluation of solar cell materials for a Solar Power Satellite  

NASA Technical Reports Server (NTRS)

Alternative solar cell materials being considered for the solar power satellite are described and price, production, and availability projections through the year 2000 are presented. The chief materials considered are silicon and gallium arsenide.

Glaser, P. E.; Almgren, D. W.; Csigi, K. I.

1980-01-01

151

Printing efficient solar cells  

Microsoft Academic Search

As worldwide demand for fossil fuels depletes reserves, scien- tists are increasingly focused on generating alternative energy— especially if it can be produced cleanly and inexpensively. Hy- droelectric, solar, wind, nuclear, and biomass technologies are replacing coal, oil, and natural gas. Many of these new tech- nologies have similar costs. Yet the availability of materials or existing infrastructure can affect

Ritesh Tipnis; Darin Laird

2008-01-01

152

Silicon concentrator solar cell research  

SciTech Connect

This report describes work conducted between December 1990 and May 1992 continuing research on silicon concentrator solar cells. The objectives of the work were to improve the performance of high-efficiency cells upon p-type substrates, to investigate the ultraviolet stability of such cells, to develop concentrator cells based on n-type substrates, and to transfer technology to appropriate commercial environments. Key results include the identification of contact resistance between boron-defused areas and rear aluminum as the source of anomalously large series resistance in both p- and n-type cells. A major achievement of the present project was the successful transfer of cell technology to both Applied Solar Energy Corporation and Solarex Corporation.

Green, M.A.; Zhao, J.; Wang, A.; Dai, X.; Milne, A.; Cai, S.; Aberle, A.; Wenham, S.R. [Univ. of New South Wales, Kensington, NSW (AU). Centre for Photovoltaic Devices and Systems

1993-06-01

153

Experimenting with Photoelectrochemical Cells in Drinking Straws: Practical Aids for Learning about Solar Energy in School or at Home  

ERIC Educational Resources Information Center

Photoelectrochemical cells using dye-sensitized ZnO with a Cu[superscript 2+]/Fe[superscript 2+]/Fe[superscript 3+] electrolyte can be easily made at home or in a school classroom with household chemicals and other readily available materials. The cells, which are made with wire housed within plastic drinking straws, have open-circuit voltages of…

Appleyard, S. J.

2008-01-01

154

High-efficiency silicon solar cell research  

NASA Technical Reports Server (NTRS)

High efficiency solar cells were characterized. Silicon solar cell computer modeling was presented. New designs of matter insulator n-p (MINP) were discussed and a new structure called a floating emitter cell was proposed for 20% and higher efficiency. Various techniques for making high efficiency silicon solar cells were described.

Daud, T.

1984-01-01

155

Phthalocyanine based Schottky solar cells  

NASA Astrophysics Data System (ADS)

Phthalocyanine (Pc) materials are commonly used in organic solar cells. Four different phthalocyanines, nickel phthalocyanine (NiPc), copper phthalocyanine (CuPc), iron phthalocyanine (FePc), and cobalt phthalocyanine (CoPc) have been investigated for organic solar cell applications. The devices consisted of indium tin oxide (ITO) coated lass substrate, Pc layer, and aluminum (al) electrode. It has been found that ITO/CuPc/Al Schottky cell exhibits the best performance. To investigate the influence of the active layer thickness on the cell performance, cells with several different thicknesses were fabricated and optimal value was found. Schottky cell exhibits optimal performance with one ohmic and one barrier contact. However, it is suspected that ITO/CuPc contact is not ohmic. Therefore, we have investigated various ITO surface treatments for improving the performance of CuPc based Schottky solar cell. We have found that cell on ITO treated with HCl and UV-ozone exhibits the best performance. AM1 power conversion efficiency can be improved by 30% compared to cell made with untreated ITO substrate. To improve power conversion efficiency, double or multiplayer structure are required, and it is expected that suitable ITO treatments for those devices will further improve their performance by improving the contact between ITO and phthalocyanine layer.

Kwong, Chung Yin; Djurisic, Aleksandra B.; Lam, Lillian S. M.; Chan, Wai Kin

2003-02-01

156

Chlorine and bromine solar neutrino experiments  

SciTech Connect

The solar neutrino experiment based upon the neutrino capture reaction /sup 37/Cl (..nu.., e/sup -/) /sup 37/Ar has been in operation in the Homestake Gold Mine at Lead, South Dakota since 1967. The results of this experiment are well known, and have been reported most recently to the solar neutrino conference at Lead in 1984. We report here the latest results from this experiment. A radiochemical neutrino detector based upon the neutrino capture reaction /sup 81/Br (..nu.., e/sup -/) /sup 81/Kr* ..-->.. /sup 81/Kr has recently been shown to be feasible. Our plans for performing a full scale test of the method using the Homestake chlorine detector are discussed briefly. 8 refs.

Davis, R. Jr.; Cleveland, B.T.; Rowley, J.K.

1985-01-01

157

Report on solar-neutrino experiments  

NASA Astrophysics Data System (ADS)

The results of the chlorine detector are summarized, and an account made of the plans to build a gallium solar neutrino experiment. In addition to discussing the experimental side of the solar neutrino problem the experiences during the last 15 years in working in the Homestake Gold Mine are related. A number of independent groups have asked to use the facilities and, because of the cooperative and helpful attitude of the Mine management, these experimentalists were easily accommodated. A brief account of these experiences is useful for the main business of this workshop, building large particle detectors for observing nucleon decay, and the related question of the need for a national underground physics facility.

Davis, R., Jr.

158

TROPIX: A solar electric propulsion flight experiment  

NASA Technical Reports Server (NTRS)

The Transfer Orbit Plasma Interaction Experiment (TROPIX) is a proposed scientific experiment and flight demonstration of a solar electric propulsion vehicle. Its mission goals are to significantly increase our knowledge of Earth's magnetosphere and its associated plasma environment and to demonstrate an operational solar electric upper stage (SEUS) for small launch vehicles. The scientific investigations and flight demonstration technology experiments are uniquely interrelated because of the spacecraft's interaction with the surrounding environment. The data obtained will complement previous studies of the Earth's magnetosphere and space plasma environment by supplying the knowledge necessary to attain the strategic objectives of the NASA Office of Space Science. This first operational use of a primary ion propulsion vehicle, designed to withstand the harsh environments from low Earth orbit to geosynchronous Earth orbit, may lead to the development of a new class of electric propulsion upper stages or space-based transfer vehicles and may improve future spacecraft design and safety.

Hickman, J. Mark; Hillard, G. Barry; Oleson, Steven R.

1993-01-01

159

Spectral coupling of fluorescent solar concentrators to plasmonic solar cells  

NASA Astrophysics Data System (ADS)

Coupling luminescent solar concentrators (LSC) with plasmonic solar cells is a potential method to increase conversion efficiency while reducing cost associated with large-area photovoltaic and solar-tracking systems. Specifically, the emission spectrum of the fluorescent dye in the LSC can be matched to the absorption spectrum in the photovoltaic cell which can be tuned by surface plasmon resonance. Here we investigate this concept employing organic solar cells with plasmonic silver nanoparticles and polymethylmethacrylate-based solar concentrators with Lumogen Red dye. The absorption enhancement is predicted by Mie theory, taking size effect on dielectric properties into consideration. A factor of two increase of conversion efficiency is obtained when the absorption peak in the solar cell is tuned to match the emission peak of Lumogen Red dye. A similar approach could be employed to enhance the efficiency of other LSC-photovoltaic systems including those based on silicon solar cells with different surface plasmonic nanostructures.

Wang, Shu-Yi; Borca-Tasciuc, Diana-Andra; Kaminski, Deborah A.

2011-04-01

160

Solar cell circuit and method for manufacturing solar cells  

NASA Technical Reports Server (NTRS)

The invention is a novel manufacturing method for making multi-junction solar cell circuits that addresses current problems associated with such circuits by allowing the formation of integral diodes in the cells and allows for a large number of circuits to readily be placed on a single silicon wafer substrate. The standard Ge wafer used as the base for multi-junction solar cells is replaced with a thinner layer of Ge or a II-V semiconductor material on a silicon/silicon dioxide substrate. This allows high-voltage cells with multiple multi-junction circuits to be manufactured on a single wafer, resulting in less array assembly mass and simplified power management.

Mardesich, Nick (Inventor)

2010-01-01

161

Materials International Space Station Experiment (MISSE) 5 Developed to Test Advanced Solar Cell Technology Aboard the ISS  

NASA Technical Reports Server (NTRS)

The testing of new technologies aboard the International Space Station (ISS) is facilitated through the use of a passive experiment container, or PEC, developed at the NASA Langley Research Center. The PEC is an aluminum suitcase approximately 2 ft square and 5 in. thick. Inside the PEC are mounted Materials International Space Station Experiment (MISSE) plates that contain the test articles. The PEC is carried to the ISS aboard the space shuttle or a Russian resupply vehicle, where astronauts attach it to a handrail on the outer surface of the ISS and deploy the PEC, which is to say the suitcase is opened 180 deg. Typically, the PEC is left in this position for approximately 1 year, at which point astronauts close the PEC and it is returned to Earth. In the past, the PECs have contained passive experiments, principally designed to characterize the durability of materials subjected to the ultraviolet radiation and atomic oxygen present at the ISS orbit. The MISSE5 experiment is intended to characterize state-of-art (SOA) and beyond photovoltaic technologies.

Wilt, David M.

2004-01-01

162

Key Physical Mechanisms in Nanostructured Solar Cells  

SciTech Connect

The objective of the project was to study both theoretically and experimentally the excitation, recombination and transport properties required for nanostructured solar cells to deliver energy conversion efficiencies well in excess of conventional limits. These objectives were met by concentrating on three key areas, namely, investigation of physical mechanisms present in nanostructured solar cells, characterization of loss mechanisms in nanostructured solar cells and determining the properties required of nanostructured solar cells in order to achieve high efficiency and the design implications.

Dr Stephan Bremner

2010-07-21

163

Solar neutrino experiments: Past, present, and future  

SciTech Connect

Solar neutrino detection started 25 years ago by the famous radiochemical chlorine experiment installed by Davis and his collaborators. Neutrinos produce radioactive [sup 37]Ar atoms (T[sub 1/2] = 35 days). Standard solar models (SSM) predict a value between 6.4 and 8 SNU (1 SNU or solar neutrino unit is 10[sup [minus]36] capture/atom/second) and Davis observes 2.3 [plus minus] 0.25 SNU. This reduction by a factor of about 3 is known as the solar neutrino problem. Since 1988 the real time Kamiokande experiment measures a solar neutrino flux also reduced by a factor of about 2(0.49 [+-] 0.04 [+-] 0.06 of SSM predictions). The reaction threshold either in the chlorine (>0.814MeV) or in the Kamiokande (>7.5MeV) experiments is too high to be sensitive to neutrinos produced in the primary pp fusion reaction (E[sub max] = 0.42 MeV). From 1990, a new generation of radiochemical experiments, using gallium as a target (0.233 MeV reaction threshold) started to take data. The first result of SAGE (20[sup +15][sub [minus]20](stat.) [+-] 32(syst.) SNU) has not been confirmed by GALLEX which published, in June 1992, 83 [+-]19 (stat.) [+-] 8 (syst.) SNU (SSM predictions between 124 and 132 SNU). In 1992 SAGE did not confirm its low value using its 1991 data (58[sup +17][sub [minus]24](stat.) [+-] 14(syst.) SNU, preliminary) and its final result should not be too far from the GALLEX one. GALLEX observes about 2/3 of the expected signal, almost 2[sigma] below SSM predictions. This constitutes the first evidence for the pp fusion reaction in the core of the Sun. Interpretations of the flux reductions observed are discussed in terms of astrophysics (reduction of the central temperature of the Sun) or of neutrino oscillations. The future of solar neutrino experiments (Sudbury, SuperKamiokande and Borexino) is briefly presented.

Vignaud, D.

1993-01-01

164

Silicon Formation for Solar Cells  

NASA Technical Reports Server (NTRS)

Highly pure silicon obtained for solar cells by proposed technique that sprays liquid-sodium droplets into SiF4 gas. Resulting freely flowing powder of silicon and sodium fluoride will not adhere to reactor walls and easily transferred to melt separator to recover silicon.

Sancier, K.

1985-01-01

165

Method of fabricating solar cells  

Microsoft Academic Search

This patent describes a method of fabricating a solar cell. It comprises providing a substrate in the form of a silicon ribbon having front and back surfaces and a polygonal edge configuration formed by a series of side edge surfaces; using a source of phosphorus to form a PN junction in the substrate so that the junction extends adjacent to

R. H. Micheels; P. Valdivia; J. I. Hanoka

1992-01-01

166

Dye-sensitized solar cells  

Microsoft Academic Search

The dye-sensitized solar cells (DSC) provides a technically and economically credible alternative concept to present day p–n junction photovoltaic devices. In contrast to the conventional systems where the semiconductor assume both the task of light absorption and charge carrier transport the two functions are separated here. Light is absorbed by a sensitizer, which is anchored to the surface of a

Michael Grätzel

2003-01-01

167

Compensated amorphous silicon solar cell  

DOEpatents

An amorphous silicon solar cell incorporates a region of intrinsic hydrogenated amorphous silicon fabricated by a glow discharge wherein said intrinsic region is compensated by P-type dopants in an amount sufficient to reduce the space charge density of said region under illumination to about zero.

Carlson, David E. (Yardley, PA)

1980-01-01

168

Solar cells: past, present, future  

Microsoft Academic Search

This paper gives an up to date perspective of PV technology and materials. The most important material has been and still is silicon. It dominates the present world market, particularly in its crystalline form but amorphous silicon is also of importance. Crystalline silicon solar cells are still heavily dependent on the materials base of the semiconductor industry. This material still

Adolf Goetzberger; Joachim Luther; Gerhard Willeke

2002-01-01

169

New methods for solar cells measurement by LED solar simulator  

Microsoft Academic Search

A solar simulator for solar cells is an important tool to measure their performance. At present, xenon and halogen lamp is used at most laboratories. It is considerably accurate, but the facility is so large and so expensive. Therefore, a solar simulator using LED (light-emitting diode) lamps is proposed, that is low-cost and portable, and was invented to its capability.

S. Kohraku; K. Kurokawa

2003-01-01

170

Solar cell crack inspection by image processing  

Microsoft Academic Search

Spacecraft operate in a hostile environment, far from the Earth, so it is necessary for solar cells with anti-radiation properties to have a bonding process carried out on them. After bonding, an essential process for the solar cell assembly is to inspect for cracks on the edges or inside the solar cell. To avoid utilizing unqualified products and to improve

Fu Zhuang; Zhao Yanzheng; Liu Yang; Cao Qixin; Chen Mingbo; Zhang Jun; Jay Lee

2004-01-01

171

Performance limitations of silicon solar cells  

Microsoft Academic Search

This paper discusses the performance limitations of silicon solar cells which have been identified and investigated using a detailed numerical analysis of solar cell operation. Efficiency limitations are discussed as related to doping densities, minority carrier lifetimes, widths of solar cell regions, surface recombination, antireflecting layers, and ohmic contact stripes. Areas in which improvements can be expected in performance are

JOHN R. HAUSER; PETER M. DUNBAR

1977-01-01

172

Method of fabricating solar cell modules  

Microsoft Academic Search

The solar cell module of this invention is fabricated by placing an array of solar cells in a suitable mold having a bottom surface, an entry port and an exit port. A light transparent superstrate effectively serves as the top for the mold and is placed over the array of solar cells in the mold. The superstrate is spaced from

W. B. Andrulitis; W. T. Kurth; S. G. Miles

1980-01-01

173

Implications of the solar neutrino experiments  

NASA Astrophysics Data System (ADS)

The recent results from the KAMIOKANDE II and BAKSAN solar neutrino experiments, if correct, imply that lepton flavour is not conserved. The Mikheyev-Smirnov-Wolfenstein (MSW) solution to the solar neutrino problem, which was first exposed by the HOMESTAKE Cl experiment, fully explains also these results if the electron neutrino is mixed with the muon neutrino or the tau neutrino with mixing parameters ?m2 ~ 10-6cV-2 and sin22? ~ 4 × 10-2. This MSW solution can be tested with the new generation of solar neutrino experiments which will be able to detect both the predicted distortion of the spectrum of 8B solar ve's and the ``missing'' ve's that appear as v?'s or v?'s. Further evidence may be obtained from the day-night effect and from the flavour content of the neutronization burst from the birth of a neutron star in a nearby supernova. Moreover, the MSW solution combined with the seesaw mechanism for generating neutrino masses further suggests mve ~ 10-8eV, mv? ~ 10-3cV, mv? ~ 10 cV, and sin22? ~ 4 × 10 -2 for v?v? mixing. These predictions can be tested by previously proposed neutrino oscillation experiments at accelerators and by detecting neutrinos from a nearby supernova explosion. A tau neutrino with mv? ~ 10eV can account for most of the dark matter in the Universe and is a viable candidate for the hot dark matter scenario of the formation of large scale structure in the Universe.

Dar, Arnon; Nussinov, Shmuel

1992-07-01

174

Adsorption of organic dyes on TiO2 surfaces in dye-sensitized solar cells: interplay of theory and experiment.  

PubMed

First-principles computer simulations can contribute to a deeper understanding of the dye/semiconductor interface lying at the heart of Dye-sensitized Solar Cells (DSCs). Here, we present the results of simulation of dye adsorption onto TiO(2) surfaces, and of their implications for the functioning of the corresponding solar cells. We propose an integrated strategy which combines FT-IR measurements with DFT calculations to individuate the energetically favorable TiO(2) adsorption mode of acetic acid, as a meaningful model for realistic organic dyes. Although we found a sizable variability in the relative stability of the considered adsorption modes with the model system and the method, a bridged bidentate structure was found to closely match the FT-IR frequency pattern, also being calculated as the most stable adsorption mode by calculations in solution. This adsorption mode was found to be the most stable binding also for realistic organic dyes bearing cyanoacrylic anchoring groups, while for a rhodanine-3-acetic acid anchoring group, an undissociated monodentate adsorption mode was found to be of comparable stability. The structural differences induced by the different anchoring groups were related to the different electron injection/recombination with oxidized dye properties which were experimentally assessed for the two classes of dyes. A stronger coupling and a possibly faster electron injection were also calculated for the bridged bidentate mode. We then investigated the adsorption mode and I(2) binding of prototype organic dyes. Car-Parrinello molecular dynamics and geometry optimizations were performed for two coumarin dyes differing by the length of the ?-bridge separating the donor and acceptor moieties. We related the decreasing distance of the carbonylic oxygen from the titania to an increased I(2) concentration in proximity of the oxide surface, which might account for the different observed photovoltaic performances. The interplay between theory/simulation and experiments appears to be the key to further DSCs progress, both concerning the design of new dye sensitizers and their interaction with the semiconductor and with the solution environment and/or an electrolyte upon adsorption onto the semiconductor. PMID:23108504

Anselmi, Chiara; Mosconi, Edoardo; Pastore, Mariachiara; Ronca, Enrico; De Angelis, Filippo

2012-12-14

175

New trends for solar cell development and recent progress of dye sensitized solar cells  

Microsoft Academic Search

This article reviews the new concepts and new trends of solar cell development. To increase the photoelectric conversion efficiency,\\u000a reduce the cost, and for application in a much broader field, thin film solar cell, flexible solar cell, and tandem solar\\u000a cell have become important subjects to be studied. As the representative of the solar cells of the third generation, the

Hong Lin; Wen-li Wang; Yi-zhu Liu; Xin Li; Jian-bao Li

2009-01-01

176

GaAs Solar Cell Radiation Handbook  

NASA Technical Reports Server (NTRS)

The handbook discusses the history of GaAs solar cell development, presents equations useful for working with GaAs solar cells, describes commonly used instrumentation techniques for assessing radiation effects in solar cells and fundamental processes occurring in solar cells exposed to ionizing radiation, and explains why radiation decreases the electrical performance of solar cells. Three basic elements required to perform solar array degradation calculations: degradation data for GaAs solar cells after irradiation with 1 MeV electrons at normal incidence; relative damage coefficients for omnidirectional electron and proton exposure; and the definition of the space radiation environment for the orbit of interest, are developed and used to perform a solar array degradation calculation.

Anspaugh, B. E.

1996-01-01

177

Towards stable silicon nanoarray hybrid solar cells.  

PubMed

Silicon nanoarray hybrid solar cells benefit from the ease of fabrication and the cost-effectiveness of the hybrid structure, and represent a new research focus towards the utilization of solar energy. However, hybrid solar cells composed of both inorganic and organic components suffer from the notorious stability issue, which has to be tackled before the hybrid solar cells could become a viable alternative for harvesting solar energy. Here we show that Si nanoarray/PEDOT:PSS hybrid solar cells with improved stability can be fabricated via eliminating the water inclusion in the initial formation of the heterojunction between Si nanoarray and PEDOT:PSS. The Si nanoarray hybrid solar cells are stable against rapid degradation in the atmosphere environment for several months without encapsulation. This finding paves the way towards the real-world applications of Si nanoarray hybrid solar cells. PMID:24430057

He, W W; Wu, K J; Wang, K; Shi, T F; Wu, L; Li, S X; Teng, D Y; Ye, C H

2014-01-01

178

Nanostructured Materials for Solar Cells  

NASA Technical Reports Server (NTRS)

The use of both inorganic and organic nanostructured materials in producing high efficiency photovoltaics is discussed in this paper. Recent theoretical results indicate that dramatic improvements in device efficiency may be attainable through the use of semiconductor quantum dots in an ordinary p-i-n solar cell. In addition, it has also recently been demonstrated that quantum dots can also be used to improve conversion efficiencies in polymeric thin film solar cells. A similar improvement in these types of cells has also been observed by employing single wall carbon nanotubes. This relatively new carbon allotrope may assist both in the disassociation of excitons as well as carrier transport through the composite material. This paper reviews the efforts that are currently underway to produce and characterize these nanoscale materials and to exploit their unique properties.

Bailey, Sheila; Raffaelle, Ryne; Castro, Stephanie; Fahey, S.; Gennett, T.; Tin, P.

2003-01-01

179

Super-Kamiokande experiment and solar neutrinos  

NASA Astrophysics Data System (ADS)

Super-Kmaiokande (SK) is a 50,000 ton cylindrical water Cherenkov detector located 1000m underground in Gifu prefecture in Japan. The experiment has started in 1996 aiming to study atmospheric, solar and supernova neutrinos and to search for proton decay in order to test grand unified theories. The purpose of the solar neutrino study in SK is to find a definitive evidence of solar neutrino oscillations. More than four years of the data acquisition time, SK has provided very precise measurement of the flux and the spectrum. The spectrum is consistent with no distortion and the night flux is slightly higher than the day flux, but it is not significant. However those precise determination of the flux has provided important information on the neutrino mixing angles. The MSW small mixing angle solutions (SMA) and Vacuum Oscillation (Just-So) solutions require the spectrum to be distorted. Therefore the non-observation of the distortion places a strong constraint on those solutions. At about 95% C.L. the SMA and Just-So solutions are disfavored by the spectrum shape and the day-night flux differences without any additional information of the absolute flux of solar neutrinos. The flux independent (or solar model independent) measurement of SK alone strongly indicates large mixings. In conjunction with the SNO CC data, the solar neutrino oscillations are clearly demonstrated independent of the solar model calculations, and it is now necessary to know the true oscillation parameters, especially for the mass difference. If the MSW large mixing angle solutions (LMA) is the correct solution, we expect a small, but positive day/night asymmetry. Therefore we are now improving a detector performance to reduce systematics and improve the sensitivities. If LOW or Quasi-Vacuum is the correct solution, the smoking gun evidence can be obtained by the information from pp and 7Be neutrinos. There are several such efforts. Some of those experiments can also be applicable to search for dark matter and neutrino-less double beta decay.

Suzuki, Yoichiro

2001-10-01

180

Cascade Solar Cell Workshop report  

NASA Technical Reports Server (NTRS)

Issues related to the feasibility, research and development, and demonstration of a 30% AMO cascade solar cell discussed include the material selection, growth and fabrication techniques, and device development strategy for a monolithic (two terminal) cascade cell, a hybrid (four terminal) cascade cell, and a spectral splitting device (three cells). Workshop recommendations include: (1) initiate a long range research program to develop a three junction, monolithic, cascade cell using either AlGaAsSb-GaAsSb or AlGaInAs-GaInAs material system; (2) emphasize OM-CVD epitaxial growth technique, perhaps combined with other technologies in the near term to obtain tunnel junctions; (3) develop a two junction device first; (4) initiate a cascade solar cell modeling program to study and compare performance of two and four terminal cascade devices exposed to electron and proton irradiation; and (5) encourage and be open to new ideas for developing four terminal, hybrid, cascade cells exploiting novel component cell interconnect technologies.

Hutchby, J. A.

1980-01-01

181

Mixed ternary heterojunction solar cell  

DOEpatents

A thin film heterojunction solar cell and a method of making it has a p-type layer of mixed ternary I-III-VI.sub.2 semiconductor material in contact with an n-type layer of mixed binary II-VI semiconductor material. The p-type semiconductor material includes a low resistivity copper-rich region adjacent the back metal contact of the cell and a composition gradient providing a minority carrier mirror that improves the photovoltaic performance of the cell. The p-type semiconductor material preferably is CuInGaSe.sub.2 or CuIn(SSe).sub.2.

Chen, Wen S. (Seattle, WA); Stewart, John M. (Seattle, WA)

1992-08-25

182

Point contact silicon solar cells  

NASA Technical Reports Server (NTRS)

The construction of a 22.2% efficient single-crystal silicon solar cell fabricated at Stanford University is described. The cell dimensions were 3 x 5 mm and 100 microns thick with a base lifetime of 500 microseconds. The cell featured light trapping between a texturized top surface and a reflective bottom surface, small point contact diffusions, alternating between n-type and p-type in a polka-dot pattern on the bottom surface, and a surface passivation on all surfaces between contact regions.

Swanson, R. M.

1986-01-01

183

Biological solar cell  

SciTech Connect

Recent reports have demonstrated the possibility of employing photoactive, biological membrane components in photoelectrochemical cells. Present studies in our laboratories have led to the attachment of a much simpler biological complex, the bacterial photosynthetic reaction center isolated from Rhodopseudomonas sphaeroides, directly onto a SnO/sub 2/ semiconductor electrode. Light-induced photovoltages (70mV) and photocurrents (0.5 ..mu..A/cm/sup 2/) not attributable to Dember effects have been observed in photoelectrochemical cells employing reaction-center-coated, SnO/sub 2/ working electrodes. Such reaction-center electrodes may serve as model systems for future organic photovoltaic devices.

Seibert, M.; Janzen, A.F.

1980-04-01

184

Operational experience from solar thermal energy projects  

NASA Astrophysics Data System (ADS)

Over the past few years, Sandia National Laboratories were involved in the design, construction, and operation of a number of DOE-sponsored solar thermal energy systems. Among the systems currently in operation are several industrial process heat projects and the Modular Industrial Solar Retrofit qualification test systems, all of which use parabolic troughs, and the Shenandoah Total Energy Project, which uses parabolic dishes. Operational experience has provided insight to both desirable and undesirable features of the designs of these systems. Features of these systems which are also relevant to the design of parabolic concentrator thermal electric systems are discussed. Other design features discussed are system control functions which were found to be especially convenient or effective, such as local concentrator controls, rainwash controls, and system response to changing isolation. Drive systems are also discussed with particular emphasis of the need for reliability and the usefulness of a manual drive capability.

Cameron, C. P.

1984-03-01

185

Solar cells: Folding photons  

NASA Astrophysics Data System (ADS)

Scientists have shown that wrinkles and folds can be used to maximize the absorption of low-energy photons by efficiently redirecting them into a thin absorbing film. This inexpensive technique for structuring photonic substrates could be used to increase the efficiency of many organic photovoltaic cells.

Gregg, Brian A.; van de Lagemaat, Jao

2012-05-01

186

Nanostructured upconverters for improved solar cell performance  

NASA Astrophysics Data System (ADS)

Triplet-triplet annihilation photon upconversion (TTA-UC) is a promising candidate for mitigating sub-band gap absorption losses in solar cells. In TTA-UC, sensitiser dyes absorb sub-band gap photons, cross to a triplet state, and transfer triplet excitons to emitter dyes. Two triplet-excited emitters can undergo TTA, raising one emitter to a higher-energy bright singlet state. The quadratic efficiency of TTA-UC at device-relevant light intensities motivates a push towards the higher chromophore densities achievable in the solid phase. We have begun this process by tethering tetrakisquinoxalino palladium porphyrin to 20nm silica nanoparticles using peptide chemistry techniques, achieving a total-volume concentration of 1.5mM. The phosphorescence kinetics of the tethered porphyrins was measured to quantify quenching by rubrene emitter. Upconverter performance was measured in a solar cell enhancement experiment.

MacQueen, Rowan W.; Schulze, Tim F.; Khoury, Tony; Cheng, Yuen Yap; Stannowski, Bernd; Lips, Klaus; Crossley, Maxwel J.; Schmidt, Timothy

2013-09-01

187

Enhancement of output performance of Cu2ZnSnS4 thin film solar cells—A numerical simulation approach and comparison to experiments  

NASA Astrophysics Data System (ADS)

The formation of stable, low resistance and nonrectifying contacts to Cu2ZnSnS4 (CZTS) thin film photovoltaic material are the major and critical challenges associated with its effect over the output performance of fabricated solar cells. The solution of continuity equation in one dimension for a soda lime glass substrates (SLG) |Mo | CZTS | CdS | ZnO:Al cell structure is considered in the simulation of its current-voltage characteristics that is governed by the back contact material, acceptor concentration as well as thickness of the CZTS layer. Our primary simulation shows a 6.44% efficiency of the CZTS solar cell which is comparable to reported experimental data if these parameters are not optimized. However, by optimizing them a simulated conversion efficiency as high as 13.41% (Voc=1.002 V, Jsc=19.31 mA/cm2, fill factor (FF)=69.35%) could be achievable. The solar cell with a back contact metal work function of 5.5 eV, an absorber layer's thickness of 2.68 ?m and an acceptor concentration of 5×1016 cm-3 were optimum. The presented optimization is ideal and subject to experimental verification with a precise control of the process parameters along with reduced surface as well as bulk recombination, secondary phases and thermalization losses.

Patel, Malkeshkumar; Ray, Abhijit

2012-11-01

188

Solar Cell Simulation  

NSDL National Science Digital Library

In this activity, learners model the flow of energy from the sun as it enters a photovoltaic cell, moves along a wire and powers a load. The game-like atmosphere engages younger learners and helps them understand the continuous nature of the flow of energy. Note: to do this activity you need access to a large open area outside (e.g., a field or playground).

Schleith, Susan; Hall, Penny

2007-01-01

189

Compensated amorphous silicon solar cell  

DOEpatents

An amorphous silicon solar cell including an electrically conductive substrate, a layer of glow discharge deposited hydrogenated amorphous silicon over said substrate and having regions of differing conductivity with at least one region of intrinsic hydrogenated amorphous silicon. The layer of hydrogenated amorphous silicon has opposed first and second major surfaces where the first major surface contacts the electrically conductive substrate and an electrode for electrically contacting the second major surface. The intrinsic hydrogenated amorphous silicon region is deposited in a glow discharge with an atmosphere which includes not less than about 0.02 atom percent mono-atomic boron. An improved N.I.P. solar cell is disclosed using a BF.sub.3 doped intrinsic layer.

Devaud, Genevieve (629 S. Humphrey Ave., Oak Park, IL 60304)

1983-01-01

190

Dye-Sensitized Solar Cells  

NSDL National Science Digital Library

This lesson from The Lawrence Hall of Science was taught in spring 2012 and teaches students about nano and environmental technologies. Students will create "dye-sensitized solar cells (DSSC) using nano-crystalline titanium dioxide." This page includes links to the Source Articles for the Hands-on Module and Project Staff Write-ups of the Hands-on Module. Additionally, five documents provide lecture and lab materials for instructor use.

2014-06-03

191

Solar Cells for Lunar Application  

NASA Technical Reports Server (NTRS)

In this work a preliminary study of the vacuum evaporation of silicon extracted from the lunar regolith has been undertaken. An electron gun vacuum evaporation system has been adapted for this purpose. Following the calibration of the system using ultra high purity silicon deposited on Al coated glass substrates, thin films of lunar Si were evaporated on a variety of crystalline substrates as well as on glass and lightweight 1 mil (25 microns) Al foil. Extremely smooth and featureless films with essentially semiconducting properties were obtained. Optical absorption analysis sets the bandgap (about 1.1 eV) and the refractive index (n=3.5) of the deposited thin films close to that of crystalline silicon. Secondary ion mass spectroscopy and energy dispersive spectroscopy analysis indicated that these films are essentially comparable to high purity silicon and that the evaporation process resulted in a substantial reduction of impurity levels. All layers exhibited a p-type conductivity suggesting the presence of a p-type dopant in the fabricated layers. While the purity of the 'lunar waste material' is below that of the 'microelectronic-grade silicon', the vacuum evaporated material properties seems to be adequate for the fabrication of average performance Si-based devices such as thin film solar cells. Taking into account solar cell thickness requirements (greater than 10 microns) and the small quantities of lunar material available for this study, solar cell fabrication was not possible. However, the high quality of the optical and electronic properties of evaporated thin films was found to be similar to those obtained using ultra-high purity silicon suggest that thin film solar cell production on the lunar surface with in situ resource utilization may be a viable approach for electric power generation on the moon.

Freundlich, Alex; Ignatiev, Alex

1997-01-01

192

High Temperature Solar Cell Development  

NASA Technical Reports Server (NTRS)

The majority of satellites and near-earth probes developed to date have used photovoltaic arrays for power generation. If future mission to probe environments close to the sun will be able to use photovoltaic power, solar cells that can function at high temperatures, under high light intensity, and high radiation conditions must be developed. In this paper, we derive the optimum bandgap as a function of the operating temperature.

Landis, Geoffrey A.; Raffaelle, Ryne P.; Merritt, Danielle

2004-01-01

193

MIS and SIS solar cells  

Microsoft Academic Search

This review paper shows that MIS (metal-insulator-semiconductor) and SIS (semiconductor-insulator-semiconductor) solar cells are basically one and the same type of device, even though they are usually regarded as being separate and are reported as such. Experimental results on the two most common systems, Al-Si(x)-pSi and ITO-SiO(x)-pSi (ITO designates indium-tin-oxide) are presented to support a model where tunnel current through the

J. Shewchun; D. Burk; M. B. Spitzer

1980-01-01

194

Institutional barriers to solar energy: early HUD demonstration experiences  

Microsoft Academic Search

After briefly describing the Residential Solar Demonstration Program of HUD, several of the program experiences are discussed. The HUD program found that, in practice, most institutions presented only minor problem for active solar heating and cooling of homes. Demonstration experiences suggest solutions to problems which may arise outside the program, particularly as solar applications other than heating and cooling becomemore

G. Mara; D. Engel

1980-01-01

195

Route towards high efficiency single phase Cu2ZnSn(S, Se)4 thin film solar cells: Model experiments and literature review  

Microsoft Academic Search

Thin film chalcogenide kesterites Cu2ZnSnS4 and Cu2ZnSnSe4 (CZTSSe) are promising candidates for the next generation thin film solar cells. They exhibit a high natural abundance of all constituents, a high absorption coefficient and a tunable direct bandgap between 1.0–1.5 eV. A prerequisite for the use of CZTSSe as absorber layers in photovoltaic applications on large scales is a detailed knowledge

Alex Redinger; Dominik M. Berg; Phillip J. Dale; Nathalie Valle; Susanne Siebentritt

2011-01-01

196

Recent Advances in Solar Cell Technology  

NASA Technical Reports Server (NTRS)

The advances in solar cell efficiency, radiation tolerance, and cost over the last decade are reviewed. Potential performance of thin-film solar cells in space are discussed, and the cost and the historical trends in production capability of the photovoltaics industry are considered with respect to the requirements of space power systems. Concentrator cells with conversion efficiency over 30%, and nonconcentrating solar cells with efficiency over 25% are now available, and advanced radiation-tolerant cells and lightweight, thin-film arrays are both being developed. Nonsolar applications of solar cells, including thermophotovoltaics, alpha- and betavoltaics, and laser power receivers, are also discussed.

Landis, Geoffrey A.; Bailey, Sheila G.; Piszczor, Michael F., Jr.

1996-01-01

197

Solar Coronal Cells as Seen by STEREO  

NASA Video Gallery

The changes of a coronal cell region as solar rotation carries it across the solar disk as seen with NASA's STEREO-B spacecraft. The camera is fixed on the region (panning with it) and shows the pl...

198

Interdigitated back contact solar cells. Annual report  

Microsoft Academic Search

The interdigitated back-contact solar cell (IBC cell) has been shown to possess a number of advantages for silicon solar cells, which operate at high concentration. The purpose of the present program is to support the Sandia Laboratory effort to optimize the IBC cell. A detailed discussion of the factors which need to be considered in the analysis of semiconducting devices

M. S. Lundstrom; R. J. Schwartz

1980-01-01

199

Current status of silicon solar cell technology  

Microsoft Academic Search

In quest of higher efficiency, major progress has occurred in solar cell technology during the last five years. In this period cell efficiency has climbed about 50 percent. Technical approaches leading to increased output include back surface fields (n+-p-p+structures), shallow junctions, improved antireflection coatings, surface texturizing, and fine grid patterns on the cell surface. The status of current solar cell

H. W. Jr

1975-01-01

200

Double-Sided Solar Cell Package.  

National Technical Information Service (NTIS)

A solar cell array for terrestrial use is described. The solar cell package consists of a double sided photovoltaic cell having a metallized P contact and N contact provided on opposite faces of the cell; a transparent tubular body forming a transparent e...

B. Shelpuk

1978-01-01

201

Silicon solar cell fabrication technology  

NASA Technical Reports Server (NTRS)

The laser cell scanner was used to characterize a number of solar cells made in various materials. An electron beam-induced current (EBIC) study was performed using a stereoscan scanning electron microscope. Planar p-n junctions were analyzed. A theory for the EBIC based on the analytical solution of the ambipolar diffusion equation under the influence of electron beam excitation parameter z (which is related to beam penetration), the junction depth Z sub j, the beam current and the surface recombination, was formulated and tested. The effect of a grain boundary was studied.

Stafsudd, O. M.

1979-01-01

202

Three-junction solar cell  

DOEpatents

A photovoltaic solar cell is formed in a monolithic semiconductor. The cell contains three junctions. In sequence from the light-entering face, the junctions have a high, a medium, and a low energy gap. The lower junctions are connected in series by one or more metallic members connecting the top of the lower junction through apertures to the bottom of the middle junction. The upper junction is connected in voltage opposition to the lower and middle junctions by second metallic electrodes deposited in holes 60 through the upper junction. The second electrodes are connected to an external terminal.

Ludowise, Michael J. (Cupertino, CA) [Cupertino, CA

1986-01-01

203

Extended Temperature Solar Cell Technology Development  

NASA Technical Reports Server (NTRS)

Future NASA missions will require solar cells to operate both in regimes closer to the sun, and farther from the sun, where the operating temperatures will be higher and lower than standard operational conditions. NASA Glenn is engaged in testing solar cells under extended temperature ranges, developing theoretical models of cell operation as a function of temperature, and in developing technology for improving the performance of solar cells for both high and low temperature operation.

Landis, Geoffrey A.; Jenkins, Phillip; Scheiman, David; Rafaelle, Ryne

2004-01-01

204

heat treatment for solar cells  

NASA Astrophysics Data System (ADS)

CdTe is an important compound semiconductor for solar cells, and its use in nanowire-based heterostructures may become a critical requirement, owing to the potential scarcity of tellurium. The effects of the CdCl2 heat treatment are investigated on the physical properties of vertically aligned ZnO/CdTe core-shell nanowire arrays grown by combining chemical bath deposition with close space sublimation. It is found that recrystallization phenomena are induced by the CdCl2 heat treatment in the CdTe shell composed of nanograins: its crystallinity is improved while grain growth and texture randomization occur. The presence of a tellurium crystalline phase that may decorate grain boundaries is also revealed. The CdCl2 heat treatment further favors the chlorine doping of the CdTe shell with the formation of chlorine A-centers and can result in the passivation of grain boundaries. The absorption properties of ZnO/CdTe core-shell nanowire arrays are highly efficient, and more than 80% of the incident light can be absorbed in the spectral range of the solar irradiance. The resulting photovoltaic properties of solar cells made from ZnO/CdTe core-shell nanowire arrays covered with CuSCN/Au back-side contact are also improved after the CdCl2 heat treatment. However, recombination and trap phenomena are expected to operate, and the collection of the holes that are mainly photo-generated in the CdTe shell from the CuSCN/Au back-side contact is presumably identified as the main critical point in these solar cells.

Consonni, Vincent; Renet, Sébastien; Garnier, Jérôme; Gergaud, Patrice; Artús, Lluis; Michallon, Jérôme; Rapenne, Laetitia; Appert, Estelle; Kaminski-Cachopo, Anne

2014-05-01

205

Analysis on dye-sensitized solar cell's efficiency improvement  

Microsoft Academic Search

The influence of Iph, I0, Rs, Rsh, n on the I-V curve, which are the equivalent circuit parameters of a dye-sensitized solar cell, was presented. A series of TiO2-based dye-sensitized solar cells were prepared, and experiment results consisted with our theoretical deduction that the increase of Rs would change the FF of DSSC while none influence on short-circuit current Isc,

Hanmin Tian; Jiyuan Zhang; Yangjing; Tao Yu; Zhigang Zou

2011-01-01

206

Status of multijunction solar cells  

NASA Technical Reports Server (NTRS)

This paper describes Applied Solar's present activity on Multijunction (MJ) space cells. We have worked on a variety of MJ cells, both monolithic and mechanically stacked. In recent years, most effort has been directed to GaInP2/GaAs monolithic cells, grown on Ge substrates, and the status of this cell design will be reviewed here. MJ cells are in demand to provide satellite power because of the acceptance of the overwhelming importance of high efficiency to reduce the area, weight and cost of space PV power systems. The need for high efficiencies has already accelerated the production of GaAs/Ge cells, with efficiencies 18.5-19%. When users realized that MJ cells could provide higher efficiencies (from 22% to 26%) with only fractional increase in costs, the demand for production MJ cells increased rapidly. The main purpose of the work described is to transfer the MOCVD growth technology of MJ high efficiency cells to a production environment, providing all the space requirements of users.

Yeh, Y. C. M.; Chu, C. L.

1996-01-01

207

Radiochemical Solar Neutrino Experiments - Successful and Otherwise.  

SciTech Connect

Over the years, several different radiochemical systems have been proposed as solar neutrino detectors. Of these, two achieved operating status and obtained important results that helped to define the current field of neutrino physics: the first solar-neutrino experiment, the Chlorine Detector ({sup 37}Cl) that was developed by chemist Raymond Davis and colleagues at the Homestake Mine, and the subsequent Gallium ({sup 71}Ga) Detectors that were operated by (a) the SAGE collaboration at the Baksan Laboratory and (b) the GALLEX/GNO collaborations at the Gran Sasso National Laboratory. These experiments have been extensively discussed in the literature and in many previous International Neutrino Conferences. In this paper, I present important updates to the results from SAGE and GALLEX/GNO. I also review the principles of the radiochemical detectors and briefly describe several different detectors that have been proposed. In light of the well-known successes that have been subsequently obtained by real-time neutrino detectors such as Kamiokande, Super-Kamiokande, SNO, and KamLAND, I do not anticipate that any new radiochemical neutrino detectors will be built. At present, only SAGE is still operating; the Chlorine and GNO radiochemical detectors have been decommissioned and dismantled.

Hahn,R.L.

2008-05-25

208

Laboratory experiments simulating solar wind driven magnetospheres  

SciTech Connect

Magnetosphere-solar wind interactions are simulated in a laboratory setting with a small permanent magnet driven by two types of supersonic plasma wind sources. The first higher speed, shorter duration plasma wind is from a laser blow-off plasma while the second longer duration, lower speed plasma wind is produced with a capacitor discharge driven coaxial electrode creating plasma jets. The stand off distance of the solar wind from the magnetosphere was measured to be 1.7{+-}0.3 cm for the laser-produced plasma experiment and 0.87{+-}0.03 cm for the coaxial electrode plasma experiment. The stand off distance of the plasma was calculated using data from HYADES[J. T. Larsen and S. M. Lane, J. Quant. Spectrosc. Radiat. Transf. 51, 179 (1994)] as 1.46{+-}0.02 cm for the laser-produced plasma, and estimated for the coaxial plasma jet as r{sub mp}=0.72{+-}0.07 cm. Plasma build up on the poles of the magnets, consistent with magnetosphere systems, was also observed.

Brady, P.; Ditmire, T. [Fusion Research Center, The University of Texas at Austin, Austin, Texas 78712 (United States); Horton, W.; Mays, M. L. [Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States); Zakharov, Y. [Institute of Laser Physics, Russian Academy of Sciences, Novosibirsk 630090, Av. Lavrentyeva 13/3 (Russian Federation)

2009-04-15

209

Solar Mass Ejection Imager (SMEI) space experiment  

NASA Astrophysics Data System (ADS)

The Solar Mass Ejection Imager (SMEI) is a proof-of-concept space experiment designed to observe solar coronal mass ejections (CMEs) and forecast their arrival at Earth. SMEI will image CMEs by sensing sunlight scattered from the free electrons in these ejecta (i.e., Thomson scattering). SMEI will be launched by a Titan II rocket into a circular, 830-km, sun-synchronous orbit in mid-2002 as part of the Space Test Program's CORIOLIS mission. SMEI will image nearly the entire sky once per spacecraft orbit over a mission lifetime of three years. Successful operation of SMEI will represent a major step in improving space weather forecasts by providing one- to three-day predictions of geomagnetic storms at the Earth. The SMEI experiment is being designed and constructed by a team of scientists and engineers from the Air Force Research Laboratory, the University of Birmingham (UB) in the United Kingdom, the University of California at San Diego (UCSD), and Boston University. The Air Force, NASA, and UB are providing financial support.

Radick, Richard R.

2001-12-01

210

Investigation of Sustained Arc under Solar Cell  

NASA Astrophysics Data System (ADS)

We have so far studied the sustained arc between solar array strings using solar array coupons. The solar cells are connected electrically in series by interconnectors. The interconnector is conductor and is weld at both backside and top of cells. The solar array paddle undergoes the mechanical stress due to thermal cycles in orbit. This stress may cause the separation of interconnector welding backside of cells. If the interconnector is separated from the cell, the string circuit is opened. However solar cells can generate voltage. If the separated interconnector attached to the cell again, the current can flow. If the path between interconnector and cell is formed by insulated adhesive, sustained arc can occur between the separated interconnector and cell. In this paper, the sustained arc between interconnector and cells was investigated experimentally.

Toyoda, Kazuhiro; Cho, Mengu; Kawakita, Shirou; Takahashi, Masato

211

Energy Conversion: Nano Solar Cell  

NASA Astrophysics Data System (ADS)

Problems of fossil-fuel-induced climate change have sparked a demand for sustainable energy supply for all sectors of economy. Most laboratories continue to search for new materials and new technique to generate clean energy at affordable cost. Nanotechnology can play a major role in solving the energy problem. The prospect for solar energy using Si-based technology is not encouraging. Si photovoltaics can produce electricity at 20-30 cslash/kWhr with about 25% efficiency. Nanoparticles have a strong capacity to absorb light and generate more electrons for current as discovered in the recent work of organic and dye-sensitized cell. Using cheap preparation technique such as screen-printing and self-assembly growth, organic cells shows a strong potential for commercialization. Thin Films research group at National University Malaysia has been actively involved in these areas, and in this seminar, we will present a review works on nanomaterials for solar cells and particularly on hybrid organic solar cell based on ZnO nanorod arrays. The organic layer consisting of poly[2-methoxy-5-(2-ethylhexyloxy)-1, 4-phenylenevinylene] (MEHPPV) and [6, 6]-phenyl C61-butyric acid 3-ethylthiophene ester (PCBE) was spin-coated on ZnO nanorod arrays. ZnO nanorod arrays were grown on FTO glass substrates which were pre-coated with ZnO nanoparticles using a low temperature chemical solution method. A gold electrode was used as the top contact. The device gave a short circuit current density of 2.49×10-4 mA/cm2 and an open circuit voltage of 0.45 V under illumination of a projector halogen light at 100 mW/cm2.

Yahaya, Muhammad; Yap, Chi Chin; Mat Salleh, Muhamad

2009-09-01

212

Bypass diode for a solar cell  

DOEpatents

Bypass diodes for solar cells are described. In one embodiment, a bypass diode for a solar cell includes a substrate of the solar cell. A first conductive region is disposed above the substrate, the first conductive region of a first conductivity type. A second conductive region is disposed on the first conductive region, the second conductive region of a second conductivity type opposite the first conductivity type.

Rim, Seung Bum (Palo Alto, CA); Kim, Taeseok (San Jose, CA); Smith, David D. (Campbell, CA); Cousins, Peter J. (Menlo Park, CA)

2012-03-13

213

Solar Cell Modules With Improved Backskin  

DOEpatents

A laminated solar cell module comprises a front light transmitting support, a plurality of interconnected solar cells encapsulated by a light-transmitting encapsulant material, and an improved backskin formed of an ionomer/nylon alloy. The improved backskin has a toughness and melting point temperature sufficiently great to avoid any likelihood of it being pierced by any of the components that interconnect the solar cells.

Gonsiorawski, Ronald C. (Danvers, MA)

2003-12-09

214

Epitaxial thin-film Si solar cells  

Microsoft Academic Search

Most types of thin-film solar cells imply a radical departure from the dominant bulk crystalline Si technology. This is not the case for epitaxial thin-film solar cells. In this technology, a high quality Si layer is deposited epitaxially on a low-cost Si substrate (e.g. cast Upgraded Metallurgical Grade silicon or high-throughput Si ribbons) and processed into a solar cell. This

G. Beaucarne; F. Duerinckx; I. Kuzma; K. Van Nieuwenhuysen; H. J. Kim; J. Poortmans

2006-01-01

215

Potential of amorphous silicon for solar cells  

Microsoft Academic Search

.   This paper reviews recent developments in the field of amorphous-silicon-based thin-film solar cells and discusses potentials\\u000a for further improvements. Creative efforts in materials research, device physics, and process engineering have led to highly\\u000a efficient solar cells based on amorphous hydrogenated silicon. Sophisticated multijunction solar cell designs make use of\\u000a its unique material properties and strongly suppress light induced degradation.

B. Rech; H. Wagner

1999-01-01

216

Dye-sensitized nanocrystalline solar cells  

Microsoft Academic Search

The basic physical and chemical principles behind the dye-sensitized nanocrystalline solar cell (DSC: also known as the Gratzel cell after its inventor) are outlined in order to clarify the differences and similarities between the DSC and conventional semiconductor solar cells. The roles of the components of the DSC (wide bandgap oxide, sensitizer dye, redox electrolyte or hole conductor, counter electrode)

Laurence M. Peter

2007-01-01

217

Solar cell system having alternating current output  

NASA Technical Reports Server (NTRS)

A monolithic multijunction solar cell was modified by fabricating an integrated circuit inverter on the back of the cell to produce a device capable of generating an alternating current output. In another embodiment, integrated curcuit power conditioning electronics was incorporated in a module containing a solar cell power supply.

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

1980-01-01

218

Search for new solar cell heats up  

SciTech Connect

Researchers are in the process of developing an organic solar energy cell with a plasticlike material that simplifies the complicated process of creating a working cell - one that is cheap, easy to produce and has a variety of potential applications. The chemical is polyacetylene and can be painted on anything to become a solar cell.

Lipkin, R.

1990-11-05

219

The FIELDS experiment for Solar Probe Plus  

NASA Astrophysics Data System (ADS)

Many of our basic ideas on the plasma physics of acceleration, energy flow, and dissipation, and structure of the solar wind have never been rigorously confronted by direct experimental measurements in the region where these processes are actually occurring. Although Alfven waves, shocks, and magnetic reconnection are often invoked as heating mechanisms, there have never been any direct measurements of Alfvenic waves nor the associated Poynting flux nor any measurements of ion or electron kinetic energy flux in the region from 10 R_s to 30 R_s where the final stages of wind acceleration are believed to occur. The radial profiles of both slow and fast solar wind acceleration are based on remote-sensing measurements and have been obtained for only a few selected events. Thus, the spatial radial and perpendicular scales of the acceleration process have been averaged by line-of-sight effects and the possibility of intense localized acceleration cannot be ruled out. The Solar Probe Plus (SPP) mission calls for the high quality fields and particles measurements required to solve the coronal heating and wind acceleration problem. The SPP 'FIELDS' experiment measures the electric and magnetic fields fundamental to the plasma physics of the structured and turbulent solar wind, flux ropes, collisionless shocks, and magnetic reconnection. FIELDS will make the first-ever measurements of the DC/Low-Frequency electric field inside of 1 AU allowing for in situ, high cadence measurements of the Poynting vector, the Elsasser variables, and E/B diagnostics of the wave spectrum to fce in the solar wind. SPP/FIELDS measures the radio wave (type III and II) signatures of microflares, energized electrons, and CME propagation. SPP/ FIELDS measures the plasma electron density to ~2% accuracy and the core electron temperature to ~5-10% accuracy more than 90% of the time at perihelion. FIELDS will also measure the in situ density fluctuation spectrum and structures at a very high cadence (? 10 kHz) and provide definitive signatures of the turbulent nature and heating of the solar wind plasma. Furthermore, SPP/FIELDS measures the impact rate and sig- natures of dust from micron- to nano-scales, by measuring the voltage signature of dust impacts on the spacecraft. FIELDS will also measure the floating potential of the SPP spacecraft, which is essential for correcting in situ electron data. The SPP/FIELDS experiment combines four (4) deployable electric antennas, fluxgate and search coil magnetometers and the associated signal processing electronics into a scientifically and technically integrated package. SPP/FIELDS makes very high cadence measurements of fields and density and employs an internal burst memory for intelligent data selection. FIELDS is required to measure very large plasma potentials and electric fields (~10V) and uses floating ground (+/- 100V) power preamplifiers. The SPP/FIELDS team has performed 3D plasma simulations of the SPP spacecraft plasma environ- ment, which reveal enormous voltage fluctuation levels in the plasma wake behind the spacecraft. This voltage noise dominates the true signal by orders of magnitude in the critical DC/LF frequency range. Therefore, we are proposing a design which places the four (4) electric antennas in front of the spacecraft ahead of the heat shield.

Bale, S.; Spp/Fields Team

2010-12-01

220

Aligned Si nanowire-based solar cells  

NASA Astrophysics Data System (ADS)

Si nanowires (Si NWs), as one of the fundamental building blocks for nano sciences and technologies, have attracted significant attention recently for solar cell applications, owing to the following: (1) Si NWs can significantly reduce materials consumption, and thus the solar cells fabrication cost; (2) NWs' capability to decouple light trapping and carrier collection, which is critical to achieve high power conversion efficiency. In this paper, recent progress on aligned-Si-NW-based solar cells are reviewed from optical and electrical characteristics to experimental demonstrations. Based on the understanding of each preparation process, the issues regarding the realization of highly efficient Si NW based solar cells are discussed.

Li, Junshuai; Yu, Hongyu; Li, Yali

2011-12-01

221

Laser-assisted solar cell metallization processing  

NASA Technical Reports Server (NTRS)

Laser-assisted processing techniques for producing high-quality solar cell metallization patterns are being investigated, developed, and characterized. The tasks comprising these investigations are outlined.

Rohatgi, A.; Gupta, S.; Mcmullin, P. G.; Palaschak, P. A.

1985-01-01

222

Solar cells using quantum funnels.  

PubMed

Colloidal quantum dots offer broad tuning of semiconductor bandstructure via the quantum size effect. Devices involving a sequence of layers comprised of quantum dots selected to have different diameters, and therefore bandgaps, offer the possibility of funneling energy toward an acceptor. Here we report a quantum funnel that efficiently conveys photoelectrons from their point of generation toward an intended electron acceptor. Using this concept we build a solar cell that benefits from enhanced fill factor as a result of this quantum funnel. This concept addresses limitations on transport in soft condensed matter systems and leverages their advantages in large-area optoelectronic devices and systems. PMID:21827197

Kramer, Illan J; Levina, Larissa; Debnath, Ratan; Zhitomirsky, David; Sargent, Edward H

2011-09-14

223

GPS patch antenna with photovoltaic solar cells for vehicular applications  

Microsoft Academic Search

This paper describes the application of photovoltaic (PV) solar cells in planar antenna structures. The radiating patch element of a planar antenna is replaced by a solar cell. The original feature of a solar cell (DC current generation) remains, but additionally the cell is now able to receive and transmit electromagnetic waves. Both single solar cells as well as solar

Norbert Henze; Andre Giere; Henning Früchting; Pascal Hofmann

2003-01-01

224

Front contact solar cell with formed emitter  

DOEpatents

A bipolar solar cell includes a backside junction formed by an N-type silicon substrate and a P-type polysilicon emitter formed on the backside of the solar cell. An antireflection layer may be formed on a textured front surface of the silicon substrate. A negative polarity metal contact on the front side of the solar cell makes an electrical connection to the substrate, while a positive polarity metal contact on the backside of the solar cell makes an electrical connection to the polysilicon emitter. An external electrical circuit may be connected to the negative and positive metal contacts to be powered by the solar cell. The positive polarity metal contact may form an infrared reflecting layer with an underlying dielectric layer for increased solar radiation collection.

Cousins, Peter John (Menlo Park, CA)

2012-07-17

225

Method for processing silicon solar cells  

DOEpatents

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

Tsuo, Y. Simon (Golden, CO); Landry, Marc D. (Lafayette, CO); Pitts, John R. (Lakewood, CO)

1997-01-01

226

Method for processing silicon solar cells  

DOEpatents

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

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

1997-05-06

227

Solar power satellites - Heat engine or solar cells  

NASA Technical Reports Server (NTRS)

A solar power satellite is the energy-converting element of a system that can deliver some 10 GW of power to utilities on the earth's surface. We evaluated heat engines and solar cells for converting sunshine to electric power at the satellite. A potassium Rankine cycle was the best of the heat engines, and 50 microns thick single-crystal silicon cells were the best of the photovoltaic converters. Neither solar cells nor heat engines had a clear advantage when all factors were considered. The potassium-turbine power plant, however, was more difficult to assemble and required a more expensive orbital assembly base. We therefore based our cost analyses on solar-cell energy conversion, concluding that satellite-generated power could be delivered to utilities for around 4 to 5 cents a kWh.

Oman, H.; Gregory, D. L.

1978-01-01

228

Monolithic and mechanical multijunction space solar cells  

NASA Technical Reports Server (NTRS)

High-efficiency, lightweight, radiation-resistant solar cells are essential to meet the large power requirements of future space missions. Single-junction cells are limited in efficiency. Higher cell efficiencies could be realized by developing multijunction, multibandgap solar cells. Monolithic and mechanically stacked tandem solar cells surpassing single-junction cell efficiencies have been fabricated. This article surveys the current status of monolithic and mechanically stacked multibandgap space solar cells, and outlines problems yet to be resolved. The monolithic and mechanically stacked cells each have their own problems related to size, processing, current and voltage matching, weight, and other factors. More information is needed on the effect of temperature and radiation on the cell performance. Proper reference cells and full-spectrum range simulators are also needed to measure efficiencies correctly. Cost issues are not addressed, since the two approaches are still in the developmental stage.

Jain, Raj K.; Flood, Dennis J.

1992-01-01

229

Concepts of learning and experience in developing solar thermal technologies  

Microsoft Academic Search

This study presents a picture of development of solar thermal technology, using the learning and experience curve concepts. The cost estimates for solar thermal energy technologies are made assuming a fixed production process, characterized by standard capacity factors, overhead, and labor costs. The learning curve is suggested as a generalization of the costs of potential solar energy system. The concept

F Krawiec

1983-01-01

230

New Solar Cell Power Supply System Using a Boost Type Bidirectinal DC-DC Converter  

Microsoft Academic Search

A new solar cell power supply system is presented, in which the boost type bidirectional dc-dc converter and the simple control circuit with a small monitor solar cell are employed to track the maximum power point of the solar array. It is confirmed by the experiment that the new system has sufficiently precise tracking operation performance and satisfactorily high power

Hirofumi Matsuo; Fujio Kurokawa

1984-01-01

231

Improving Polymer Solar Cell Through Efficient Solar Energy Harvesting  

Microsoft Academic Search

\\u000a In the last few years, several effective approaches have been developed to improve polymer solar cell performance. In this\\u000a chapter, we summarized several of the efforts conducted in UCLA on polymer solar cells, of which each is associated to efficient\\u000a light harvesting. We first discussed effective approaches to improve morphology and nanoscale structure control on the polymer\\u000a active layer through

Hsiang-Yu Chen; Zheng Xu; Gang Li; Yang Yang

2010-01-01

232

Theoretical temperature dependence of solar cell parameters  

NASA Astrophysics Data System (ADS)

A simple formulation has been derived for the temperature dependence of cell parameters for any solar cell material. Detailed calculations have been performed for high-quality monocrystalline GaAs, Si and Ge cells. Preliminary experimental data for GaAs and Si cells are close to the calculated values. In general, the higher the energy gap of a material, the small is the temperature dependence of its solar cell parameters.

Fan, John C. C.

1986-05-01

233

Current and lattice matched tandem solar cell  

DOEpatents

A multijunction (cascade) tandem photovoltaic solar cell device is fabricated of a Ga.sub.x In.sub.1-x P (0.505.ltoreq.X.ltoreq.0.515) top cell semiconductor lattice matched to a GaAs bottom cell semiconductor at a low-resistance heterojunction, preferably a p+/n+ heterojunction between the cells. The top and bottom cells are both lattice matched and current matched for high efficiency solar radiation conversion to electrical energy.

Olson, Jerry M. (Lakewood, CO)

1987-01-01

234

Matching of multi junction solar cells for solar array production  

Microsoft Academic Search

The current matching of multi junction solar cells determines the most important cell characteristics, such as efficiency and degradation hardness. The evaluation of current-voltage curves under different spectral irradiances enables a quantitative assessment of the device. Especially the variation of one cell's fill factor clearly indicates the shift in the current matching. A minimal fill factor can be observed at

R. Adelhelm; G. La Roche

2000-01-01

235

An overview of the first results on the solar array passive LDEF experiment (sample), AO171  

NASA Technical Reports Server (NTRS)

Space environmental effects were visibly obvious on components of experiment AO171 which contained solar cells, composites, polymeric thin films, solar reflectors, protective coatings, metals, paints , and elastomers. Micrometeoroid/space debris impacts were observed on all experiment elements. Luminescence of polyimide, silicone, and polyurethane materials occurred under black light examination. Outgassing of RTV511 occurred mainly as a result of insufficient thermal vacuum bakeout. Solar cell degradation was predominantly below 10 percent. Elastomers lost mass and discolored; composites showed evidence of atomic oxygen attack, and unprotected thin polymer films eroded away.

Whitaker, Ann F.; Young, Leighton E.

1991-01-01

236

Influence of morphology and polymer:nanoparticle ratio on device performance of hybrid solar cells-an approach in experiment and simulation.  

PubMed

We present a thorough study on the various impacts of polymer:nanoparticle ratios on morphology, charge generation and device performance in hybrid solar cells, comprising active layers consisting of a conjugated polymer and in situ prepared copper indium sulfide (CIS) nanoparticles. We conducted morphological studies through transmission electron microscopy and transient absorption measurements to study charge generation in absorber layers with polymer:nanoparticle weight ratios ranging from 1:3 to 1:15. These data are correlated to the characteristic parameters of the prepared solar cells. To gain a deeper understanding of our experimental findings, three-dimensional drift-diffusion-based simulations were performed. Based on elaborate descriptions of the contributions of polymer and nanoparticle phase to device performances, our results suggest that a polymer:CIS volume ratio of 1:2 (weight ratio 1:9) is necessary to obtain a balanced hole and electron percolation. Also at higher CIS loadings the photocurrent remains surprisingly high due to the contribution of the CIS phase to the charge carrier generation. PMID:24196417

Arar, Mario; Gruber, Manfred; Edler, Michael; Haas, Wernfried; Hofer, Ferdinand; Bansal, Neha; Reynolds, Luke X; Haque, Saif A; Zojer, Karin; Trimmel, Gregor; Rath, Thomas

2013-12-01

237

Multifolded polymer solar cells on flexible substrates  

NASA Astrophysics Data System (ADS)

Arrays of reflective multijunction polymer solar cell were demonstrated by folding four separated cells fabricated on a single plastic substrate using conducting polymer poly(3, 4-ethylene-dioxythiophene):polystyrenesulfonate as an anode. The combination of flexible substrate and polymer solar cells (PSCs) makes the construction of multifolded PSCs on one substrate possible. The power conversion efficiency (PCE) of the multifolded reflective PSCs was enhanced by 62%+/-12% with the folded opening angle of 30° compared to the planar cells. In series connection of four solar cells, an open-circuit voltage (Voc) of 3.65 V was obtained.

Zhou, Yinhua; Zhang, Fengling; Tvingstedt, Kristofer; Tian, Wenjing; Inganäs, Olle

2008-07-01

238

Theoretical Investigation on Heterojunction Solar Cell.  

National Technical Information Service (NTIS)

The study of thin film solar cells has proved that the surface is rough. A two-dimensional method based on the integral equation technique to analyse thin film solar cells has been developed by DeMey et al. In this paper we present our analysis of a thin ...

K. Prema K. Geetha

1986-01-01

239

Infrared-Controlled Welding of Solar Cells  

NASA Technical Reports Server (NTRS)

Proposed apparatus for welding large arrays of solar cells to flexible circuit substrates would sense infrared emission from welding spot. Emission would provide feedback for control of welding heat. Welding platform containing optical fibers moves upward through slots in movable holding fixture to contact solar cells. Fibers pick up infrared radiation from weld area.

Paulson, R.; Finnell, S. E.; Decker, H. J.; Hodor, J. R.

1982-01-01

240

Stability\\/degradation of polymer solar cells  

Microsoft Academic Search

Polymer and organic solar cells degrade during illumination and in the dark. This is in contrast to photovoltaics based on inorganic semiconductors such as silicon. Long operational lifetimes of solar cell devices are required in real-life application and the understanding and alleviation of the degradation phenomena are a prerequisite for successful application of this new and promising technology. In this

Mikkel Jørgensen; Kion Norrman; Frederik C. Krebs

2008-01-01

241

High-voltage vertical multijunction solar cell  

Microsoft Academic Search

The vertical multijunction solar cell with covering lens is a photovoltaic device which promises efficiencies greater than that predicted under ideal conditions for any other structure. The mathematical analysis presented here illustrates this statement. In addition the structure described here is capable of a high-voltage output for small solar cell dimensions, a feature which makes this device attractive for many

R. J. Soukup

1976-01-01

242

Monolithic cascade-type solar cells  

NASA Technical Reports Server (NTRS)

Solar cells consist of a semiconductor base, a bottom cell with a band-gap energy of E1, and a top cell with a band-gap energy of E2, and 0.96 E1 1.36 eV and (0.80 E + 0.77) eV E2 (0.80 E1 + 0.92) eV. A monolithic cascade-type solar cell was prepared with an n(+)-type GaAs base, a GaInAs bottom solar cell, and a GaAiInAs top solar cell. The surface of the cell is coated with a SiO antireflection film. The efficiency of the cell is 32%.

Yamamoto, S.; Shibukawa, A.; Yamaguchi, M.

1985-01-01

243

The Russian-American Gallium solar neutrino Experiment  

SciTech Connect

The Russian-American Gallium solar neutrino Experiment (SAGE) is described. The solar neutrino flux measured by 31 extractions through October, 1993 is presented. The result of 69 {+-} 10{sub {minus}7}{sup +5} SNU is to be compared with a standard solar model prediction of 132 SNU. The status of a {sup 51}Cr neutrino source irradiation to test the overall operation of the experiment is also presented.

Elliott, S.R. [Univ. of Washington, Seattle, WA (United States); Abdurashitov, J.N. [Russian Academy of Sciences, Moscow (Russian Federation). Inst. for Nuclear Research; Bowles, T.J. [Los Alamos National Lab., NM (United States)] [and others

1995-12-31

244

The Russian-American gallium solar neutrino experiment  

SciTech Connect

The Russian-American Gallium solar neutrino Experiment (SAGE) is described. The solar neutrino flux measured by 31 extractions through October, 1993 is presented. The result of 69 {+-} 10{sub {minus}7}{sup +5} SNU is to be compared with a standard solar model prediction of 132 SNU. The status of a {sup 51}Cr neutrino source irradiation to test the overall operation of the experiment is also presented.

Elliott, S.R.; Wilkerson, J.F. [Univ. of Washington, Seattle, WA (United States); Abdurashitov, J.N. [Russian Academy of Sciences, Moscow (Russian Federation). Institute of Nuclear Research] [and others

1995-08-01

245

High-efficiency concentrator silicon solar cells  

Microsoft Academic Search

This report presents results from extensive process development in high-efficiency Si solar cells. An advanced design for a 1.56-cm(sup 2) cell with front grids achieved 26 percent efficiency at 90 suns. This is especially significant since this cell does not require a prismatic cover glass. New designs for simplified backside-contact solar cells were advanced from a status of near-nonfunctionality to

R. A. Sinton; A. Cuevas; R. R. King; R. M. Swanson

1990-01-01

246

Nanowire-based All Oxide Solar Cells  

SciTech Connect

We present an all-oxide solar cell fabricated from vertically oriented zinc oxide nanowires and cuprous oxide nanoparticles. Our solar cell consists of vertically oriented n-type zinc oxide nanowires, surrounded by a film constructed from p-type cuprous oxide nanoparticles. Our solution-based synthesis of inexpensive and environmentally benign oxide materials in a solar cell would allow for the facile production of large-scale photovoltaic devices. We found that the solar cell performance is enhanced with the addition of an intermediate oxide insulating layer between the nanowires and the nanoparticles. This observation of the important dependence of the shunt resistance on the photovoltaic performance is widely applicable to any nanowire solar cell constructed with the nanowire array in direct contact with one electrode.

Yang*, Benjamin D. Yuhas and Peidong; Yang, Peidong

2008-12-07

247

Flexible solid-state dye solar cells  

Microsoft Academic Search

The cell structure concepts and materials to build solid-state dye solar cells based on nanocristalline titanium oxide and an organic hole conductor were investigated. The substrate cell is based on a metal foil and a semi-transparent gold window on top of the cell structure and the superstrate cell is deposited on ITO coated polymer foil replacing the traditional conductive glass

Toby B. Meyer; Andreas F. Meyer; Daniel Ginestoux

2002-01-01

248

Telescience operations with the solar array module plasma interaction experiment  

NASA Astrophysics Data System (ADS)

The Solar Array Module Plasma Interactions Experiment (SAMPIE) is a flight experiment that flew on the Space Shuttle Columbia (STS-62) in March 1994, as part of the OAST-2 mission. The overall objective of SAMPIE was to determine the adverse environmental interactions within the space plasma of low earth orbit (LEO) on modern solar cells and space power system materials which are artificially biased to high positive and negative direct current (DC) voltages. The two environmental interactions of interest included high voltage arcing from the samples to the space plasma and parasitic current losses. High voltage arcing can cause physical damage to power system materials and shorten expected hardware life. parasitic current losses can reduce power system efficiency because electric currents generated in a power system drain into the surrounding plasma via parasitic resistance. The flight electronics included two programmable high voltage DC power supplies to bias the experiment samples, instruments to measure the surrounding plasma environment in the STS cargo bay, and the on-board data acquisition system (DAS). The DAS provided in-flight experiment control, data storage, and communications through the Goddard Space Flight Center (GSFC) Hitchhiker flight avionics to the GSFC Payload Operations Control Center (POCC). The DAS and the SAMPIE POCC computer systems were designed for telescience operations; this paper will focus on the experiences of the SAMPIE team regarding telescience development and operations from the GSFC POCC during STS-62. The SAMPIE conceptual development, hardware design, and system verification testing were accomplished at the NASA Lewis Research Center (LeRC). SAMPIE was developed under the In-Space Technology Experiment Program (IN-STEP), which sponsors NASA, industry, and university flight experiments designed to enable and enhance space flight technology. The IN-STEP Program is sponsored by the Office of Space Access and Technology (OSAT).

Wald, Lawrence W.; Bibyk, Irene K.

1995-09-01

249

Telescience operations with the solar array module plasma interaction experiment  

NASA Technical Reports Server (NTRS)

The Solar Array Module Plasma Interactions Experiment (SAMPIE) is a flight experiment that flew on the Space Shuttle Columbia (STS-62) in March 1994, as part of the OAST-2 mission. The overall objective of SAMPIE was to determine the adverse environmental interactions within the space plasma of low earth orbit (LEO) on modern solar cells and space power system materials which are artificially biased to high positive and negative direct current (DC) voltages. The two environmental interactions of interest included high voltage arcing from the samples to the space plasma and parasitic current losses. High voltage arcing can cause physical damage to power system materials and shorten expected hardware life. parasitic current losses can reduce power system efficiency because electric currents generated in a power system drain into the surrounding plasma via parasitic resistance. The flight electronics included two programmable high voltage DC power supplies to bias the experiment samples, instruments to measure the surrounding plasma environment in the STS cargo bay, and the on-board data acquisition system (DAS). The DAS provided in-flight experiment control, data storage, and communications through the Goddard Space Flight Center (GSFC) Hitchhiker flight avionics to the GSFC Payload Operations Control Center (POCC). The DAS and the SAMPIE POCC computer systems were designed for telescience operations; this paper will focus on the experiences of the SAMPIE team regarding telescience development and operations from the GSFC POCC during STS-62. The SAMPIE conceptual development, hardware design, and system verification testing were accomplished at the NASA Lewis Research Center (LeRC). SAMPIE was developed under the In-Space Technology Experiment Program (IN-STEP), which sponsors NASA, industry, and university flight experiments designed to enable and enhance space flight technology. The IN-STEP Program is sponsored by the Office of Space Access and Technology (OSAT).

Wald, Lawrence W.; Bibyk, Irene K.

1995-01-01

250

Silicon film solar cell process  

NASA Technical Reports Server (NTRS)

The most promising way to reduce the cost of silicon in solar cells while still maintaining performance is to utilize thin films (10 to 20 microns thick) of crystalline silicon. The method of solution growth is being employed to grow thin polycrystalline films of silicon on dissimilar substrates. The initial results indicate that, using tin as the solvent, this growth process only requires operating temperatures in the range of 800 C to 1000 C. Growth rates in the range of 0.4 to 2.0 microns per minute and grain sizes in the range of 20 to 100 microns were achieved on both quartz and coated steel substrates. Typically, an aspect ratio of two to three between the width and the Si grain thickness is seen. Uniform coverage of Si growth on quartz over a 2.5 x 2.5 cm area was observed.

Hall, R. B.; Mcneely, J. B.; Barnett, A. M.

1984-01-01

251

Heterojunction silicon microwire solar cells.  

PubMed

We report radial heterojunction solar cells of amorphous silicon on crystalline silicon microwires with high surface passivation. While the shortened collection path is exploited to increase the photocurrent, proper choice of the wire radius and the highly passivated surface prevent drastic decrease in the voltage due to high surface-to-volume ratio. The heterojunction is formed by depositing a ?12-16 nm of amorphous silicon on crystalline silicon wires of radius approximately equal to minority carrier diffusion length (?10 ?m). In spite of very short carrier lifetime (<1 ?s), the microwire array devices generate photocurrent of ?30 mA/cm(2), and the same time, voltages close to 600 mV are achieved, leading to efficiency in excess of 12% in extremely short carrier lifetime silicon. We also find that formation of nanocrystallites of silicon in the deposited film results in loss of the expected passivation. PMID:23170984

Gharghi, Majid; Fathi, Ehsanollah; Kante, Boubacar; Sivoththaman, Siva; Zhang, Xiang

2012-12-12

252

Tandem photovoltaic solar cells and increased solar energy conversion efficiency  

NASA Technical Reports Server (NTRS)

Tandem photovoltaic cells, as proposed by Jackson (1955) to increase the efficiency of solar energy conversion, involve the construction of a system of stacked p/n homojunction photovoltaic cells composed of different semiconductors. It had been pointed out by critics, however, that the total power which could be extracted from the cells in the stack placed side by side was substantially greater than the power obtained from the stacked cells. A reexamination of the tandem cell concept in view of the development of the past few years is conducted. It is concluded that the use of tandem cell systems in flat plate collectors, as originally envisioned by Jackson, may yet become feasible as a result of the development of economically acceptable solar cells for large scale terrestrial power generation.

Loferski, J. J.

1976-01-01

253

Semiconductor quantum dot-sensitized solar cells  

PubMed Central

Semiconductor quantum dots (QDs) have been drawing great attention recently as a material for solar energy conversion due to their versatile optical and electrical properties. The QD-sensitized solar cell (QDSC) is one of the burgeoning semiconductor QD solar cells that shows promising developments for the next generation of solar cells. This article focuses on recent developments in QDSCs, including 1) the effect of quantum confinement on QDSCs, 2) the multiple exciton generation (MEG) of QDs, 3) fabrication methods of QDs, and 4) nanocrystalline photoelectrodes for solar cells. We also make suggestions for future research on QDSCs. Although the efficiency of QDSCs is still low, we think there will be major breakthroughs in developing QDSCs in the future.

Tian, Jianjun; Cao, Guozhong

2013-01-01

254

Dye-sensitized Solar Cells for Solar Energy Harvesting  

NASA Astrophysics Data System (ADS)

Dye-sensitized solar cells (DSSCs) also known as Gratzel cells, have attracted the interests of researchers to a great extent because of its cost effective and easy manufacturing process without involving highly sophisticated lithographic technique and high cost raw materials as usually seen in conventional solar cell. Based on simple photo-electrochemical process, it has got immense potential in converting solar energy to electrical power in remote and desert area where the supply of conventional power is not possible. The overall peak power-production efficiency of dye-sensitized solar cells has been reported around 11 percent, so they are best suited to low-density applications and the price-to-performance ratio obtained through these solar cells is superior to others. DSSCs have ability to absorb even diffused sunlight and therefore work in cloudy whether as well without much impact over the efficiency. The present communication deals with a review of our work on DSSCs wherein we have used cost effective natural dyes/pigments as a sensitizer of nc-TiO2 and discussed about various key factors affecting the conversion efficiency of DSSC.

Roy, M. S.; Deol, Y. S.; Kumar, Manish; Prasad, Narottam; Janu, Yojana

2011-10-01

255

Development and fabrication of a solar cell junction processing system  

NASA Technical Reports Server (NTRS)

A solar cell junction processing system was developed and fabricated. A pulsed electron beam for the four inch wafers is being assembled and tested, wafers were successfully pulsed, and solar cells fabricated. Assembly of the transport locks is completed. The transport was operated successfully but not with sufficient reproducibility. An experiment test facility to examine potential scaleup problems associated with the proposed ion implanter design was constructed and operated. Cells were implanted and found to have efficiency identical to the normal Spire implant process.

Bunker, S.

1981-01-01

256

Transparent conductive oxides for thin-film silicon solar cells  

NASA Astrophysics Data System (ADS)

This thesis describes research on thin-film silicon solar cells with focus on the transparent conductive oxide (TCO) for such devices. In addition to the formation of a transparent and electrically conductive front electrode for the solar cell allowing photocurrent collection with low ohmic losses, the front TCO plays an important role for the light enhancement of thin-film silicon pin type solar cells. If the TCO is rough, light scattering at rough interfaces in the solar cell in combination with a highly reflective back contact leads to an increase in optical path length of the light. Multiple (total) internal reflectance leads to virtual 'trapping' of the light in the solar cell structure, allowing a further decrease in absorber thickness and thus thin-film silicon solar cell devices with higher and more stable efficiency. Here, the optical mechanisms involved in the light trapping in thin-film silicon solar cells have been studied, and two types of front TCO materials have been investigated with respect to their suitability as front TCO in thin-film silicon pin type solar cells. Undoped and aluminum doped zinc oxide layers have been fabricated for the first time by the expanding thermal plasma chemical vapour deposition (ETP CVD) technique at substrate temperatures between 150 º C and 350 º C, and successfully implemented as a front electrode material for amorphous silicon pin superstrate type solar cells. Solar cells with efficiencies comparable to cells on Asahi U-type reference TCO have been reproducibly obtained. A higher haze is needed for the ZnO samples studied here than for Asahi U-type TCO in order to achieve comparable long wavelength response of the solar cells. This is attributed to the different angular distribution of the scattered light, showing higher scattering intensities at large angles for the Asahi U-type TCO. A barrier at the TCO/p interface and minor collection problems may explain the slightly lower fill factors obtained for the cells on ETP ZnO. The solar cells deposited on the first doped ZnO:Al layers suffered from collection problems reducing the fill factor, and from shunting. This is attributed to the steep trenches, sharp features and vertical steps that have been identified at the TCO surface. ZnO:Al layers with granular structure, deposited at higher argon flow through the cascaded arc plasma source, allowed for fill factors of the solar cells up to 0.70, comparable to cells on undoped ZnO. The best solar cell on doped ZnO:Al deposited by ETP CVD achieved an efficiency of 9.3 % which is comparable to the 9.4 % obtained on Asahi U-type SnO2:F. Fluorinated tin oxide has been deposited by Atmospheric Chemical Vapor Deposition (APCVD) on glass from three different tin precursors, tetramethyltin, monobutyltin trichloride, and tin tetrachloride (TTC). TTC is the Sn precursor which resulted in the TCO with the best performance of a-Si:H pin solar cells. In accordance with the conclusions from our experiments with solar cells on undoped and aluminum doped zinc oxide, a high surface roughness and haze do not necessarily lead to a lower diode quality, and vice versa.

Löffler, J.

2005-04-01

257

Integration of Solar Cells on Top of CMOS Chips Part I: aSi Solar Cells  

Microsoft Academic Search

We present the monolithic integration of deep- submicrometer complementary metal-oxide-semiconductor (CMOS) microchips with a-Si:H solar cells. Solar cells are manufactured directly on the CMOS chips. The microchips maintain comparable electronic performance, and the solar cells show efficiency values above 7%. The yield of photovoltaic cells on planarized CMOS chips is 92%. This integration allows integrated energy harvesting using established process

Jiwu Lu; Alexey Y. Kovalgin; Karine H. M. van der Werf; Ruud E. I. Schropp; Jurriaan Schmitz

2011-01-01

258

Pulsed Solar Simulator for Electrical Performance Tests of Space Solar Cells/Arrays.  

National Technical Information Service (NTIS)

A pulsed xenon solar simulator, designed to cope with future measurement problems with advanced solar cells and solar cell arrays, is described. The simulator, consisting of a flash lamp, a power supply, and an operator console, is capable of illuminating...

W. Lukschal A. P. Robben

1989-01-01

259

Development of multijunction thin film solar cells  

Microsoft Academic Search

Due to the possibility of band gap engineering in Cu(In,Ga)Se2 (CIGS) absorbers and the spectral tunability of dye-sensitized solar cells (DSCs) with suitable choice of the sensitizer, this combination of solar cells could be ideal for the construction of dual junction photovoltaic devices. Factors for performance limitations of mechanically stacked tandem cells have been identified and alternative remedies are developed

S. Seyrling; S. Bucheler; A. Chirila; J. Perrenoud; S. Wenger; T. Nakada; M. Gratzel; A. N. Tiwari

2009-01-01

260

Development of gallium arsenide solar cells  

NASA Technical Reports Server (NTRS)

The potential of ion implantation as a means of developing gallium arsenide solar cells with high efficiency performance was investigated. Computer calculations on gallium arsenide cell characteristics are presented to show the effects of surface recombination, junction space-charge recombination, and built-in fields produced by nonuniform doping of the surface region. The fabrication technology is summarized. Electrical and optical measurements on samples of solar cells are included.

1973-01-01

261

Orienting and Applying Flux to Solar Cells  

NASA Technical Reports Server (NTRS)

Solar cells are oriented and fluxed automatically at first work station along solar-array assembly line. In under 2 seconds rotary drive rotates cell into proper position for applying solder flux to bus pad on collector side. When contact bus pad is in correct position, capstan drive is disengaged, and vacuum holddown beneath cell is turned on. Flux system lowers and applies preset amount of solder flux to bus pad. Two interconnect tabs are soldered to fluxed areas.

Feder, H.; Frasch, W.

1982-01-01

262

LDEF solar cell radiation effects analysis  

NASA Technical Reports Server (NTRS)

Because of the extended time that the Long Duration Exposure Facility (LDEF) mission stayed in space, the solar cells on the satellite experienced greater environments than originally planned. The cells showed an overall degradation in performance that is due to the combined effects of the various space environments. The purpose of this analysis is to calculate the effect of the accumulated radiation on the solar cells, thereby helping Marshall Space Flight Center (MSFC) to unravel the relative power degradation from the different environments.

Rives, Carol J.; Azarewicz, Joseph L.; Massengill, Lloyd

1993-01-01

263

Comprehensive silicon solar-cell computer modeling  

NASA Technical Reports Server (NTRS)

A comprehensive silicon solar cell computer modeling scheme was developed to perform the following tasks: (1) model and analysis of the net charge distribution in quasineutral regions; (2) experimentally determined temperature behavior of Spire Corp. n+pp+ solar cells where n+-emitter is formed by ion implantation of 75As or 31P; and (3) initial validation results of computer simulation program using Spire Corp. n+pp+ cells.

Lamorte, M. F.

1984-01-01

264

Dielectric films for Si solar cell applications  

Microsoft Academic Search

Thin films of many dielectric materials have been used in the past for fabrication of solar cells and as a part of their device\\u000a structure. However, current efforts to reduce solar cell costs in commercial production have led to simplification of cell\\u000a design and fabrication. Use of self-aligning techniques has obviated the need for photolithography and conventional masking\\u000a with dielectric

Bhushan Sopori

2005-01-01

265

Single-nanowire Si solar cells  

Microsoft Academic Search

Solar cells based on arrays of CVD-grown Si nano- or micro-wires are being considered as a potentially low-cost route to implementing a vertical multijunction cell design via radial p-n junctions. This geometry has been predicted to enable efficiencies competitive with planar multicrystalline Si designs, while reducing the materials and processing costs of solar cell fabrication [1]. To further assess the

M. D. Kelzenberg; D. B. Turner-Evans; B. M. Kayes; M. A. Filler; M. C. Putnam; N. S. Lewis; H. A. Atwater

2008-01-01

266

High-voltage solar-cell chip  

Microsoft Academic Search

Integrated circuit technology has been successfully applied to the design and fabrication of 0.5 x 0.5-cm planar multijunction solar-cell chips. Each of these solar cells consisted of six voltage-generating unit cells monolithically connected in series and fabricated on a 75-micron-thick, p-type, single crystal, silicon substrate. A contact photolithic process employing five photomask levels together with a standard microelectronics batch-processing technique

V. J. Kapoor; G. J. Valco; G. G. Skebe; J. C. Evans Jr.

1985-01-01

267

Assessing Possibilities & Limits for Solar Cells  

Microsoft Academic Search

What are the solar cell efficiencies that we can strive towards? We show here\\u000athat several simple criteria, based on cell and module performance data, serve\\u000ato evaluate and compare all types of today's solar cells. Analyzing these data\\u000aallows to gauge in how far significant progress can be expected for the various\\u000acell types and, most importantly from both

Pabitra K. Nayak; Juan Bisquert; David Cahen

2011-01-01

268

Silicon solar cells improved by lithium doping  

NASA Technical Reports Server (NTRS)

Results of conference on characteristics of lithium-doped silicon solar cells and techniques required for fabrication indicate that output of cells has been improved to point where cells exhibit radiation resistance superior to those currently in use, and greater control and reproducibility of cell processing have been achieved.

Berman, P. A.

1970-01-01

269

Saudi Arabia's experience in solar energy applications  

Microsoft Academic Search

The progress in solar energy research in Saudi Arabia is discussed with emphasis on the efforts of a government research entity - King Adbulaziz City for Science and Technology (KACST). Three programs currently underway at KACST are considered: the continuation of activities initiated under the Solar Energy Research American\\/Saudi (SOLERAS) program, a Saudi\\/German program, and projects developed and conducted completely

Fahad S. Huraib

1990-01-01

270

Electron irradiation of modern solar cells  

NASA Technical Reports Server (NTRS)

A number of modern solar cell types representing 1976 technology (as well as some older types) were irradiated with 1 MeV electrons (and a limited number with 2 MeV electrons and 10 MeV protons). After irradiation, the cells were annealed, with I-V curves measured under AMO at 30 C. The purpose was to provide data to be incorporated in the revision of the solar cell radiation handbook. Cell resistivities ranged from 2 to 20 ohm-cm, and cell thickness from 0.05 to 0.46 mm. Cell types examined were conventional, shallow junction, back surface field (BSF), textured, and textured with BSF.

Anspaugh, B. E.; Miyahira, T. F.

1977-01-01

271

Bypass diode for a solar cell  

DOEpatents

Methods of fabricating bypass diodes for solar cells are described. In once embodiment, a method includes forming a first conductive region of a first conductivity type above a substrate of a solar cell. A second conductive region of a second conductivity type is formed on the first conductive region. In another embodiment, a method includes forming a first conductive region of a first conductivity type above a substrate of a solar cell. A second conductive region of a second conductivity type is formed within, and surrounded by, an uppermost portion of the first conductive region but is not formed in a lowermost portion of the first conductive region.

Rim, Seung Bum; Kim, Taeseok; Smith, David D; Cousins, Peter J

2013-11-12

272

Teachers' Domain: Inside a Solar Cell  

NSDL National Science Digital Library

This interactive Flash tutorial shows how photovoltaic cells in solar panels convert sunlight into electrical current. It provides a close-up look at each layer of the basic solar panel, with particular emphasis on how electrons cross over the junction that joins the two silicon layers in the cell. When the concentration of negative and positive charge between the two layers reaches equilibrium, an electric field is produced -- the solar cell is ready to capture photons. Teachers' Domain is a collection of more than 1,000 free educational resources compiled by researchers and experienced teachers to promote the use of digital resources in the classroom.

2012-08-21

273

Temperature coefficients of multijunction solar cells  

NASA Technical Reports Server (NTRS)

Temperature coefficients measured in solar simulators with those measured under AM0 solar illumination are compared to illustrate the challenges in making these measurements. It is shown that simulator measurements of the short-circuit current (delta Jsc/delta T) are inaccurate due to the mismatch between the solar spectrum and the simulators at the bandgaps of the solar cells. Especially susceptible to error is the delta Jsc/delta T of cells which are components in monolithic multijunction solar cells, such as GaAs filtered by 1.93-eV AlGaAs, which has an AM0 coefficient of 6.82 micro-A/sq cm/deg C, compared to a Xenon simulator coefficient of 22.2 micro-A/sq cm/deg C.

Virshup, G. F.; Chung, B.-C.; Ladle Ristow, M.; Kuryla, M. S.; Brinker, D.

1990-01-01

274

Indium oxide/n-silicon heterojunction solar cells  

DOEpatents

A high photo-conversion efficiency indium oxide/n-silicon heterojunction solar cell is spray deposited from a solution containing indium trichloride. The solar cell exhibits an Air Mass One solar conversion efficiency in excess of about 10%.

Feng, Tom (Morris Plains, NJ); Ghosh, Amal K. (New Providence, NJ)

1982-12-28

275

Solar Cell Efficiency Tables (Version 33)  

Microsoft Academic Search

Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since July 2008 are reviewed. Efficiencies are updated to the new reference solar spectrum tabulated in IEC 60904-3 Ed. 2 revised in April 2008 and an updated list

Martin A. Green; Keith Emery; Yoshihiro Hishikawa; Wilhelm Warta

2009-01-01

276

Radiation degradation of solar cell arrays  

NASA Technical Reports Server (NTRS)

A method of incorporating a detailed solar cell radiation degradation model into a convenient computational scheme suitable for the solar electric propulsion system is outlined. The study shows that several existing codes may be applied in sequence to solve the problem.

Hill, C. W.

1975-01-01

277

CdS Solar Cell Development.  

National Technical Information Service (NTIS)

More than half of the initial part of this program had been concerned with the overall processing aspects of the solar cell. Equipment was designed and constructed to carry out all steps necessary to the manufacturing of thin film cadmium sulfide solar ce...

J. J. Kramer R. S. Wietubicz

1973-01-01

278

V-groove multijunction solar cells  

Microsoft Academic Search

A study of three components which can be used in a solar utilization system are described. The three components are: a photovoltaic converter, an intensity sensor, and a selective thermal absorber. The results of extensive computer simulations, theoretical analyses, and measurements are reported for these components. A new family of silicon photovoltaic devices called V-Groove Multi-Junction (VGMJ) solar cells are

T. I. Chappell

1978-01-01

279

Extended Temperature Solar Cell Technology Development.  

National Technical Information Service (NTIS)

Future NASA missions will require solar cells to operate both in regimes closer to the sun, and farther from the sun, where the operating temperatures will be higher and lower than standard operational conditions. NASA Glenn is engaged in testing solar ce...

G. A. Landis

2005-01-01

280

High-efficiency solar-cell design modeling  

NASA Astrophysics Data System (ADS)

Comprehensive computer models were developed to simulate single junction and multiple junction silicon solar cell structures. The following phenomena submodels were incorporated into computer models: effects due to temperature, impurities, defect energy levels, high injection, and surface states; front surface field, back surface field; oxide charged insulator; carrier confinement; bandgap narrowing; depletion region recombination; series resistance; metal contact shadowing; and anti-reflective coatings. Fabrication of 2 cm x 2 cm n(+)p and n(+)pp(+) near optimized silicon solar cells was done. The cells were characterized with respect to V(oc), 1(sc), P(mp), 1(mp), and eta over the temperature 25 C to 150 C. The accuracy of the computer modeling and correct phenomena submodels and/or analysis were assessed to obtain better than 5% agreement with experimental data. Phenomena that give rise to solar cell losses, were determined and quantified through analysis and experiments.

Lamorte, M. F.

1984-03-01

281

Low temperature surface passivation for silicon solar cells  

Microsoft Academic Search

Surface passivation at low processing temperatures becomes an important topic for cheap solar cell processing. In this study, we first give a broad overview of the state of the art in this field. Subsequently, the results of a series of mutually related experiments are given about surface passivation with direct Plasma Enhanced Chemical Vapour Deposition (PECVD) of silicon oxide (Si-oxide)

C. Leguijt; P. Lölgen; J. A. Eikelboom; A. W. Weeber; F. M. Schuurmans; W. C. Sinke; P. F. A. Alkemade; P. M. Sarro; C. H. M. Marée; L. A. Verhoef

1996-01-01

282

The interdigitated back contact solar cell - A silicon solar cell for use in concentrated sunlight  

Microsoft Academic Search

The theoretical and experimental performance of an interdigitated back contact solar cell is described. This type of cell is shown to have significant advantages over a conventional solar cell design when used at high concentration levels, namely, reduced internal series resistance, nonsaturating open-circuit voltage, and an absence of shadowing by front surface contacting fingers. The results of a computer study

M. D. Lammert; R. J. Schwartz

1977-01-01

283

The interdigitated back contact solar cell: A silicon solar cell for use in concentrated sunlight  

Microsoft Academic Search

The theoretical and experimental performance of an interdigitated back contact solar cell is described. This type of cell is shown to have significant advantages over a conventional solar cell design when used at high concentration levels, namely, reduced internal series resistance, nonsaturating open-circuit voltage, and an absence of shadowing by front surface contacting fingers. The results of a computer study

M. D. Lammert; R. J. Schwartz

1977-01-01

284

Towards high performance inverted polymer solar cells  

NASA Astrophysics Data System (ADS)

Bulk heterojunction polymer solar cells that can be fabricated by solution processing techniques are under intense investigation in both academic institutions and industrial companies because of their potential to enable mass production of flexible and cost-effective alternative to silicon-based electronics. Despite the envisioned advantages and recent technology advances, so far the performance of polymer solar cells is still inferior to inorganic counterparts in terms of the efficiency and stability. There are many factors limiting the performance of polymer solar cells. Among them, the optical and electronic properties of materials in the active layer, device architecture and elimination of PEDOT:PSS are the most determining factors in the overall performance of polymer solar cells. In this presentation, I will present how we approach high performance of polymer solar cells. For example, by developing novel materials, fabrication polymer photovoltaic cells with an inverted device structure and elimination of PEDOT:PSS, we were able to observe over 8.4% power conversion efficiency from inverted polymer solar cells.

Gong, Xiong

2013-03-01

285

Lessons learned from Atlanta \\/towns\\/ solar experiment  

Microsoft Academic Search

An experimental large-scale solar heating and cooling system installed at an Atlanta, Georgia site is discussed. The program emphasized development of a low-cost installation from commercially-available materials; a complete instrumentation system allowed for monitoring of the facility's performance. Details of the heating system's components, including the collector array, consisting of aluminized Mylar reflectors and solar collectors, and the storage tanks,

A. Weinstein; R. T. Duncan Jr.; W. C. Sherbin

1977-01-01

286

Space solar cells: High efficiency and radiation damage  

Microsoft Academic Search

The progress and status of efforts to increase the end-of-life efficiency of solar cells for space use is assessed. High efficiency silicon solar cells, silicon solar cell radiation damage, GaAs solar cell performance and radiation damage and 30 percent devices are discussed.

H. W. Jr. Brandhorst; D. T. Bernatowicz

1980-01-01

287

Spectral Response Measurements for Solar Cells.  

National Technical Information Service (NTIS)

An overview of spectral response measurements, measurement systems, and potential measurement problems are described relative to the characterization of solar cells. Measurement systems are outlined for determining the spectral response, external quantum ...

J. S. Hartman M. A. Lind

1981-01-01

288

The perils of solar cell efficiency measurements  

NASA Astrophysics Data System (ADS)

Ignorance and negligence are frequently causing solar cells to be mischaracterized, and invalid efficiency results have been reported in a number of journals. This problem can be greatly alleviated by employing a few simple precautions and guidelines.

Snaith, Henry J.

2012-06-01

289

Silicon Concentrator Solar Cell Manufacturing Development.  

National Technical Information Service (NTIS)

The program to design and develop the manufacturing technology for silicon solar cells sutiable for low-cost photovoltaic concentrator systems is summarized. Detailed discussions are presented for the following tasks: concentrator design, manufacturing pr...

C. Wrigley G. Storti J. Wohlgemuth

1978-01-01

290

Solar cell array design handbook, volume 1  

NASA Technical Reports Server (NTRS)

Twelve chapters discuss the following: historical developments, the environment and its effects, solar cells, solar cell filters and covers, solar cell and other electrical interconnections, blocking and shunt diodes, substrates and deployment mechanisms, material properties, design synthesis and optimization, design analysis, procurement, production and cost aspects, evaluation and test, orbital performance, and illustrative design examples. A comprehensive index permits rapid locating of desired topics. The handbook consists of two volumes: Volume 1 is of an expository nature while Volume 2 contains detailed design data in an appendix-like fashion. Volume 2 includes solar cell performance data, applicable unit conversion factors and physical constants, and mechanical, electrical, thermal optical, magnetic, and outgassing material properties. Extensive references are provided.

Rauschenbach, H. S.

1976-01-01

291

High-efficiency silicon solar cell research  

NASA Technical Reports Server (NTRS)

Progress reports on research in high-efficiency silicon solar cells were presented by eight contractors and JPL. The presentations covered the issues of Bulk and Surface Loss, Modeling, Measurements, and Proof of Concept.

Daud, T.

1984-01-01

292

Dye-sensitized solar cells  

DOEpatents

A low-cost dye-sensitized Schottky barrier solar cell comprised of a substrate of semiconductor with an ohmic contact on one face, a sensitizing dye adsorbed onto the opposite face of the semiconductor, a transparent thin-film layer of a reducing agent over the dye, and a thin-film layer of metal over the reducing agent. The ohmic contact and metal layer constitute electrodes for connection to an external circuit and one or the other or both are made transparent to permit light to penetrate to the dye and be absorbed therein for generating electric current. The semiconductor material chosen to be the substrate is one having a wide bandgap and which therefore is transparent; the dye selected is one having a ground state within the bandgap of the semiconductor to generate carriers in the semiconductor, and a first excited state above the conduction band edge of the semiconductor to readily conduct electrons from the dye to the semiconductor; the reducing agent selected is one having a ground state above the ground state of the sensitizer to provide a plentiful source of electrons to the dye during current generation and thereby enhance the generation; and the metal for the thin-film layer of metal is selected to have a Fermi level in the vicinity of or above the ground state of the reducing agent to thereby amply supply electrons to the reducing agent.

Skotheim, Terje A. (Berkeley, CA)

1980-01-01

293

Dye-sensitized solar cells  

DOEpatents

A low-cost dye-sensitized Schottky barrier solar cell is comprised of a substrate of semiconductor with an ohmic contact on one face, a sensitizing dye adsorbed onto the opposite face of the semiconductor, a transparent thin-film layer of a reducing agent over the dye, and a thin-film layer of metal over the reducing agent. The ohmic contact and metal layer constitute electrodes for connection to an external circuit and one or the other or both are made transparent to permit light to penetrate to the dye and be absorbed therein for generating electric current. The semiconductor material chosen to be the substrate is one having a wide bandgap and which therefore is transparent; the dye selected is one having a ground state within the bandgap of the semiconductor to generate carriers in the semiconductor, and a first excited state above the conduction band edge of the semiconductor to readily conduct electrons from the dye to the semiconductor; the reducing agent selected is one having a ground state above the ground state of the sensitizer to provide a plentiful source of electrons to the dye during current generation and thereby enhance the generation; and the metal for the thin-film layer of metal is selected to have a Fermi level in the vicinity of or above the ground state of the reducing agent to thereby amply supply electrons to the reducing agent. 3 figs.

Skotheim, T.A.

1980-03-04

294

Experiments on solar photovoltaic power generation using concentrator and liquid cooling  

NASA Technical Reports Server (NTRS)

Calculations and experimental data are presented leading to the development of a practical, economical solar photovoltaic power supply. The concept involves concentration of sunlight up to about 100 times normal solar intensity in a solar tracking collector and directing this to an array of solar cells. The cells are immersed in water circulated from a thermal reservoir which limits cell temperature rise to about 20 C above ambient during the day and which cools to ambient temperature during the night. Experiments were conducted on solar cells using a Fresnel lens for magnification, a telescope equatorial mount with clock drive, and tap water circulated through the solar cell holder cavity. Test results show that cells operate satisfactorily under these conditions. Power outputs achieved experimentally with cell optimized for 25 suns were linear with concentration to about 15 suns. Cells optimized for 100 suns were not available, but a corresponding linear relation of power output with concentration is anticipated. Test results have been used in a design analysis of the cost of systems utilizing this technique.

Beam, B. H.; Hansen, C. F.

1975-01-01

295

Large area polymer solar cells  

NASA Astrophysics Data System (ADS)

The fabrication of very large area polymer based solar cell modules with a total aperture area of 1000 cm2 has been accomplished. The substrate was polyethyleneterephthalate (PET) foil with a pre-etched pattern of indium-tin-oxide (ITO) anodes. The module was constructed as a matrix of 91 devices comprising 7 rows connected in parallel with each row having 13 individual cells connected in series. The printing of the organic layer employed screen printing of a chlorobenzene solution of the active material that consisted of either poly-1,4-(2-methoxy-5-ethylhexyloxy) phenylenevinylene (MEH-PPV) on its own or a 1:1 mixture (w/w) of MEH-PPV and [6,6]-phenyl-C61-butanoic acid methyl ester (PCBM). Our first results employed e-beam evaporation of the aluminium cathode directly onto the active layer giving devices with very poor performance that was discouragingly lower than expected by about three orders of magnitude. We found that e-beam radiation leads to a much poorer performance and thermal evaporation of the aluminium using a basket heater improved these values by an order of magnitude in efficiency for the geometry ITO/MEH-PPV/C60/Al. Finally the lifetimes (?1/2) of the modules were established and were found to improve significantly when a sublimed layer of C60 was included between the polymer and the aluminium electrode. Values for the half life of 150 hours were typically obtained. This short lifetime is linked to reaction between the reactive metal electrode (aluminium) and the constituents of the active layer.

Krebs, Frederik C.; Alstrup, Jan; Biancardo, Matteo; Spanggaard, Holger

2005-10-01

296

Impurity gradients and high efficiency solar cells  

NASA Technical Reports Server (NTRS)

One potential means of improving the efficiency of solar cells especially after space irradiation is to incorporate built-in fields into the device through the use of impurity doping gradients. A detailed numerical calculation of solar cell performance has been used to study various types of doping gradients. In general, the predicted improvements in performance have been less than previously reported due to various device effects such as, high injection and the dependence of lifetime on doping density.

Fang, C. R.; Hauser, J. R.

1977-01-01

297

Stretchable, wearable dye-sensitized solar cells.  

PubMed

A stretchable, wearable dye-sensitized solar-cell textile is developed from elastic, electrically conducting fiber as a counter electrode and spring-like titanium wire as the working electrode. Dyesensitized solar cells are demonstrated with energy-conversion efficiencies up to 7.13%. The high energy-conversion efficiencies can be well maintained under stretch by 30% and after stretch for 20 cycles. PMID:24648169

Yang, Zhibin; Deng, Jue; Sun, Xuemei; Li, Houpu; Peng, Huisheng

2014-05-01

298

Dye sensitized solar cells on paper substrates  

Microsoft Academic Search

This article reports for the first time in the literature, a dye sensitized solar cells with 1.21% efficiency (Voc=0.56V, Jsc=6.70mA\\/cm2 and F.F.=0.33) on paper substrates. The current dye sensitized solar cell technology is based on fluorine doped SnO2 (FTO) coated glass substrates. The problem with the glass substrate is its rigidity and heavy weight. Making DSSCs on paper opens the

Bo Wang; Lei L. Kerr

2011-01-01

299

Nanowire dye-sensitized solar cells  

Microsoft Academic Search

Excitonic solar cells-including organic, hybrid organic-inorganic and dye-sensitized cells (DSCs)-are promising devices for inexpensive, large-scale solar energy conversion. The DSC is currently the most efficient and stable excitonic photocell. Central to this device is a thick nanoparticle film that provides a large surface area for the adsorption of light-harvesting molecules. However, nanoparticle DSCs rely on trap-limited diffusion for electron transport,

Matt Law; Lori E. Greene; Justin C. Johnson; Richard Saykally; Peidong Yang

2005-01-01

300

High-temperature Solar Cell Development  

NASA Technical Reports Server (NTRS)

The vast majority of space probes to date have relied upon photovoltaic power generation. If future missions designed to probe environments close to the sun (Figure 1) will be able to use such power generation, solar cells that can function at high temperatures, under high light intensity, and high radiation conditions must be developed. The significant problem is that solar cells lose performance at high temperatures.

Landis, Geoffrey A.; Merritt, Danielle; Raffaelle, Ryne P.; Scheiman, David

2005-01-01

301

Thin film solar cells for indoor use  

Microsoft Academic Search

The effect of low irradiance for thin film solar cells is investigated in this work. First, a-Si:H\\/CIGS\\/DSSC\\/OPV four kinds of thin film solar cells are fabricated and measured with the sun simulator (AM 1.5G, 100 mW\\/cm2). Then, the saturation current density J0 is extracted from the Voc and Jsc. Spectral irradiance of the desk light, LED light, sun light at

P. C. Yang; I. M. Chan; C. H. Lin; Y. L. Chang

2011-01-01

302

Limiting efficiency of silicon solar cells  

Microsoft Academic Search

The detailed balance method for calculating the radiative recombination limit to the performance of solar cells has been extended to include free carrier absorption and Auger recombination in addition to radiative losses. This method has been applied to crystalline silicon solar cells where the limiting efficiency is found to be 29.8 percent under AM1.5, based on the measured optical absorption

TOM TIEDJE; ELI YABLONOVITCH; GEORGE D. CODY; BONNIE G. BROOKS

1984-01-01

303

Status of polycrystalline solar cell technologies  

Microsoft Academic Search

Thin-film cadmium telluride (CdTe) and thin-film copper indium diselenide (CIS) solar cells are discussed. The issues these technologies face before commercialization are addressed. The authors conclude that high-efficiency (15-18%) polycrystalline silicon modules will dominate the market in the near future, and impressive results for thin-film CdTe and CIS solar cells and their outdoor stability will attract increased interest in these

Vijay K. Kapur; Bulent M. Basol

1991-01-01

304

Hydrogen passivation of multicrystalline silicon solar cells  

Microsoft Academic Search

The use of hydrogen for passivation of multicrystalline silicon in solar cell technology is described. Three kinds of hydrogen incorporation into mc-Si solar cells have been evaluated: hydrogen diffusion out of a SiN-layer (SiN:H), low-energy hydrogen ion implantation (HII), and remote plasma hydrogen passivation (RPHP). Best results were obtained by RPHP, whereas using HII, damage exceeded the passivation effect to

Ralf Lüdemann

1999-01-01

305

Multijunction Solar Cells Optimized for the Mars Surface Solar Spectrum  

NASA Technical Reports Server (NTRS)

This paper gives an update on the performance of the Mars Exploration Rovers (MER) which have been continually performing for more than 3 years beyond their original 90-day missions. The paper also gives the latest results on the optimization of a multijunction solar cell that is optimized to give more power on the surface of Mars.

Edmondson, Kenneth M.; Fetzer, Chris; Karam, Nasser H.; Stella, Paul; Mardesich, Nick; Mueller, Robert

2007-01-01

306

MDAC solar cosmic ray experiment on OGO-6  

NASA Technical Reports Server (NTRS)

The instrumentation of the OGO-F solar cosmic ray experiment is described and results of data obtained during the satellite lifetime from launch on June 5, 1969, through September, 1970, and discussed.

Masley, A. J.

1973-01-01

307

Very thin silicon wafer base solar cell  

Microsoft Academic Search

The performance and ruggedness of very thin silicon back surface field (Bsf) solar cells are improved by the formation of a relatively thick, epitaxially grown, highly doped layer at the back of the cell and the formation of an arsenic doped layer at the top of the cell within the phosphorous diffused front region. As a result of these modifications

Mandelkorn

1982-01-01

308

Improved protection for silicon solar cells  

NASA Technical Reports Server (NTRS)

Fluorinated ethylene propylene /FEP/ film is substituted for epoxy cement in bonding glass covers to silicon solar cells. Insensitivity of FEP to ultraviolet radiation reduces requirement for filtering and does not impair cell performance. Cell costs are reduced and cover mounting is simplified.

Broder, J. D.

1970-01-01

309

Transparent superstrate terrestrial solar cell module  

NASA Technical Reports Server (NTRS)

The design, development, fabrication, and testing of the transparent solar cell module were examined. Cell performance and material process characteristics were determined by extensive tests and design modifications were made prior to preproduction fabrication. These tests included three cell submodules and two full size engineering modules. Along with hardware and test activity, engineering documentation was prepared and submitted.

1977-01-01

310

Space solar cell technology development - a perspective  

Microsoft Academic Search

The history of space solar cell development is examined and used to forecast future progress. Major challenges facing the implementation of GaAs cell technology are discussed. Areas of silicon cell development, such as configuration changes and approaches to obtaining improved space radiation resistance, which could prove significant for future mission needs are identified. It is suggested that users of silicon

Scott-Monck

1982-01-01

311

Ideal theory of quantum well solar cells  

Microsoft Academic Search

An ideal model for quantum well solar cells is developed and is used to theoretically explore the dependence of terminal characteristics on the host cell and quantum well properties. The model, which explicitly treats carrier generation and recombination in the quantum wells, is described and compared with an analogous ideal model for bulk homojunction cells. Open-circuit voltages, short-circuit current densities,

Neal G. Andersona

1995-01-01

312

Coatings Boost Solar-Cell Outputs  

NASA Technical Reports Server (NTRS)

Efficiencies increased by more-complete utilization of incident light. Electrical outputs of thin solar photovoltaic cells made of dendritic-web silicon increased by combination of front-surface, antireflective coatings and back-surface, reflective coatings. Improvements achieved recently through theoretical and experimental studies of ways to optimize coatings for particular wavelengths of incident light, cell thicknesses, and cell materials.

Rohatgi, Ajeet; Campbell, Robert B.; O'Keefe, T. W.; Rai-Choudbury, Posenjit; Hoffman, Richard A.

1988-01-01

313

Solar Energy Experiments for High School and College Students.  

ERIC Educational Resources Information Center

This publication contains eighteen experiments and eight classroom activities. The experiments are of varying difficulty and cover the important aspects of solar energy utilization. Each experiment is self-contained, with its own introduction and background information. Energy measurements are emphasized and techniques for collector efficiency…

Norton, Thomas W.; And Others

314

All solution processible polymer multijunction solar cells  

NASA Astrophysics Data System (ADS)

Conjugated polymer based organic solar cells are a promising alternative to conventional silicon solar cells due to low material and fabrication cost, ease of processability, and mechanical flexibility, while solar cells with a multijunction structure have high potential to achieve enhanced efficiency and cost effectiveness. The goal of this dissertation was to stack narrow band absorbers with efficient interfacial layers in multiple junctions for broad spectrum light harvesting to achieve cost effectiveness. Specific objectives were to develop cost effective interfacial layers, and to design and fabricate solution processible polymer single and multijunction solar cells to achieve 10 % efficiency. A novel recombination layer of Nb2O5-PEDOT:PSS was developed along with single and double junction solar cells using a MDMO-PPV:PC 60BM, P3HT:PC60BM and PSBTBT:PC70BM polymer blend. Simulations showed that the maximum achievable efficiency for single, double, triple, and quadruple junction polymer solar cells were 13 %, 19 %, 22 %, and 24 % respectively, indicating the potential of multijunction devices. XRD reveled that the Nb2O5 used as the recombination layer was amorphous and AFM and KFM microscopic studies showed that the charge transfer barrier from PC60BM to Nb2O5 was only ˜0.2 eV. A MDMO-PPV:PC60BM based double junction solar cell using Nb2O5 electron transport layer exhibited a Voc of 1.30 V, which was close to the sum of the Voc’s of the individual subcells. Simulation results showed that cell efficiency using Nb2O5 as an electron transport layer could be significantly increased by reducing the series resistance (Rse) and matching the current densities of the individual subcells. Nb2O5-PEDOT:PSS was used in a high band gap P3HT and low band gap polymer based double junction solar cell, and the performance obtained was very promising though the PSBTBT:PC 70BM back subcell appeared to be the performance limiting cell with low FF and high series and low shunt resistance. If all the single junction solar cells used as subcells are optimized, the double junction device based on this recombination layer will reach higher efficiency. Future work should include developing triple or quadruple junction solar cells using the Nb2O5 nanoparticles doped with other transitional metals as an interfacial layer along with novel donor and acceptor materials towards an efficiency greater than 10 %.

Siddiki, Mahbube Khoda

315

Optimization and performance of Space Station Freedom solar cells  

NASA Technical Reports Server (NTRS)

High efficiency, large area and low cost solar cells are the drivers for Space Station solar array designs. The manufacturing throughput, process complexity, yield of the cells, and array manufacturing technique determine the economics of the solar array design. The cell efficiency optimization of large area (8 x 8 m), dielectric wrapthrough contact solar cells are described. The results of the optimization are reported and the solar cell performance of limited production runs is reported.

Khemthong, S.; Hansen, N.; Bower, M.

1991-01-01

316

The Solar Array Module Plasma Interactions Experiment (SAMPIE): Science and technology objectives  

NASA Technical Reports Server (NTRS)

The Solar Array Module Plasma Interactions Experiment (SAMPIE) is an approved NASA Space Shuttle space flight experiment to be launched in Jul. 1993. The SAMPIE experiment is designed to investigate the interaction of high voltage space power systems with ionospheric plasma. To study the behavior of solar cells, a number of cell coupons, representing technologies of current interest, will be biased to high voltages to characterize both negative potential arcing and positive potential current collection. Additionally, various theories of arc suppression will be tested by including several specially modified cell coupons. Finally, SAMPIE will include experiments to study the basic nature of these interactions. The rationale for a space flight experiment, the measurements to be made, the significance of the expected results, and the current design status of the flight hardware are described.

Hillard, G. Barry

1992-01-01

317

Development and fabrication of a solar cell junction processing system  

NASA Technical Reports Server (NTRS)

A processing system capable of producing solar cell junctions by ion implantation followed by pulsed electron beam annealing was developed and constructed. The machine was to be capable of processing 4-inch diameter single-crystal wafers at a rate of 10(7) wafers per year. A microcomputer-controlled pulsed electron beam annealer with a vacuum interlocked wafer transport system was designed, built and demonstrated to produce solar cell junctions on 4-inch wafers with an AMI efficiency of 12%. Experiments showed that a non-mass-analyzed (NMA) ion beam could implant 10 keV phosphorous dopant to form solar cell junctions which were equivalent to mass-analyzed implants. A NMA ion implanter, compatible with the pulsed electron beam annealer and wafer transport system was designed in detail but was not built because of program termination.

1984-01-01

318

Comparative values of advanced space solar cells  

NASA Astrophysics Data System (ADS)

A methodology for deriving a first order dollar value estimate for advanced solar cells which consists of defining scenarios for solar array production and launch to orbit and the associated costs for typical spacecraft, determining that portion affected by cell design and performance and determining the attributable cost differences is presented. Break even values are calculated for a variety of cells; confirming that efficiency and related effects of radiation resistance and temperature coefficient are major factors; array tare mass, packaging and packing factor are important; but cell mass is of lesser significance. Associated dollar values provide a means of comparison.

Slifer, L. W., Jr.

1982-09-01

319

Comparative values of advanced space solar cells  

NASA Technical Reports Server (NTRS)

A methodology for deriving a first order dollar value estimate for advanced solar cells which consists of defining scenarios for solar array production and launch to orbit and the associated costs for typical spacecraft, determining that portion affected by cell design and performance and determining the attributable cost differences is presented. Break even values are calculated for a variety of cells; confirming that efficiency and related effects of radiation resistance and temperature coefficient are major factors; array tare mass, packaging and packing factor are important; but cell mass is of lesser significance. Associated dollar values provide a means of comparison.

Slifer, L. W., Jr.

1982-01-01

320

Manufacture of Solar Cells on the Moon  

NASA Technical Reports Server (NTRS)

In support of the space exploration initiative a new architecture for the production of solar cells on the lunar surface is devised. The paper discusses experimental data on the fabrication and properties of lunar glass substrates, evaporated lunar regolith thin film (antireflect coatings and insulators), and preliminary attempts in the fabrication of thin film (silicon/II-VI) photovoltaic materials on lunar regolith substrates. A conceptual design for a solar powered robotic rover capable of fabricating solar cells directly on the lunar surface is provided. Technical challenges in the development of such a facility and strategies to alleviate perceived difficulties are discussed. Finally, preliminary cost benefit ratio analysis for different in situ solar cell production scenarios (using exclusively in-situ planetary resources or hybrid) are discussed.

Freundich, Alex; Ignatiev, Alex; Horton, Charles; Duke, Mike; Curren, Peter; Sibille, Laurent

2005-01-01

321

Landsat 7 Solar Array Testing Experiences  

NASA Technical Reports Server (NTRS)

This paper covers the extensive Landsat 7 solar array flight qualification testing effort. Details of the mechanical design of the solar array and its retention/release system are presented. A testing chronology is provided beginning with the onset of problems encountered at the subsystem level and carrying through the third and final powered-spacecraft ground deployment test. Design fixes and other changes are explained in the same order as they became necessary to flight-qualify the array. Some interesting lessons learned are included along with key references.

Helfrich, Daniel

2000-01-01

322

The solar activity measurements experiments (SAMEX) for improved scientific understanding of solar activity  

NASA Technical Reports Server (NTRS)

The Solar Activity Measurements Experiments (SAMEX) mission is described. It is designed to provide a look at the interactions of magnetic fields and plasmas that create flares and other explosive events on the sun in an effort to understand solar activity and the nature of the solar magnetic field. The need for this mission, the instruments to be used, and the expected benefits of SAMEX are discussed.

1989-01-01

323

Advanced solar cells for satellite power systems  

NASA Astrophysics Data System (ADS)

The multiple natures of today's space missions with regard to operational lifetime, orbital environment, cost and size of spacecraft, to name just a few, present such a broad range of performance requirements to be met by the solar array that no single design can suffice to meet them all. The result is a demand for development of specialized solar cell types that help to optimize overall satellite performance within a specified cost range for any given space mission. Historically, space solar array performance has been optimized for a given mission by tailoring the features of silicon solar cells to account for the orbital environment and average operating conditions expected during the mission. It has become necessary to turn to entirely new photovoltaic materials and device designs to meet the requirements of future missions, both in the near and far term. This paper will outline some of the mission drivers and resulting performance requirements that must be met by advanced solar cells, and provide an overview of some of the advanced cell technologies under development to meet them. The discussion will include high efficiency, radiation hard single junction cells; monolithic and mechanically stacked multiple bandgap cells; and thin film cells.

Flood, Dennis J.; Weinberg, Irving

1994-11-01

324

Advanced solar cells for satellite power systems  

NASA Technical Reports Server (NTRS)

The multiple natures of today's space missions with regard to operational lifetime, orbital environment, cost and size of spacecraft, to name just a few, present such a broad range of performance requirements to be met by the solar array that no single design can suffice to meet them all. The result is a demand for development of specialized solar cell types that help to optimize overall satellite performance within a specified cost range for any given space mission. Historically, space solar array performance has been optimized for a given mission by tailoring the features of silicon solar cells to account for the orbital environment and average operating conditions expected during the mission. It has become necessary to turn to entirely new photovoltaic materials and device designs to meet the requirements of future missions, both in the near and far term. This paper will outline some of the mission drivers and resulting performance requirements that must be met by advanced solar cells, and provide an overview of some of the advanced cell technologies under development to meet them. The discussion will include high efficiency, radiation hard single junction cells; monolithic and mechanically stacked multiple bandgap cells; and thin film cells.

Flood, Dennis J.; Weinberg, Irving

1994-01-01

325

Design considerations for silicon HLE solar cells  

NASA Technical Reports Server (NTRS)

The high-low (H-L) junction in the emitter region that defines the high-low-junction emitter (HLE) solar cell suppresses the dark emitter recombination current J sub E so that the base recombination current dominates in determining the open-circuit voltage. For silicon cells this enables the achievement of considerably larger values of open-circuit voltage than those achievable in conventional structures. This paper describes experiments that demonstrate the achievement of J sub E suppression (to less than 5 x 10 to the -14th A/sq cm) and large open-circuit voltage (640 mV) in HLE test cells of two distinct types. In the first type (the diffused HLE structure) impurity diffusion forms the H-L junction in the emitter; in the second type (the oxide-charge-induced HLE structure) the H-L junction is formed in emitter material of relatively low doping concentration by an oxide-charge-induced electron accumulation layer.

Lindholm, F. A.; Neugroschel, A.; Pao, S. C.; Fossum, J. G.; Sah, C. T.

1978-01-01

326

Flexible solid-state dye solar cells  

NASA Astrophysics Data System (ADS)

The cell structure concepts and materials to build solid-state dye solar cells based on nanocristalline titanium oxide and an organic hole conductor were investigated. The substrate cell is based on a metal foil and a semi-transparent gold window on top of the cell structure and the superstrate cell is deposited on ITO coated polymer foil replacing the traditional conductive glass as transparent substrate. Steel, titanium and polymer foil based cell were assembled. The polymer/ITO cell gave only small currents as the materials are far from optimal in that configuration, but an efficiency of 0.8 % was obtained on a Ti-foil based cell.

Meyer, Toby B.; Meyer, Andreas F.; Ginestoux, Daniel

2002-02-01

327

Solar Cells in the School Physics Laboratory.  

ERIC Educational Resources Information Center

Discusses the goals of experiments which show examples of the use of solar energy on a scale suitable for a school laboratory. Highlights the history of discoveries and developments in photoelectricity. Presents investigations and experiments, that can be performed by students. (JRH)

Mikulski, Kazimeirz

1996-01-01

328

Solar neutrino experiments: The next generation  

Microsoft Academic Search

Three big new detectors are addressing the puzzle of the persistent solar-neutrino deficit. Is it the Sun, or the neutrino, that{close_quote}s behaving so strangely? We may soon know for certain. {copyright} {ital 1996 American Institute of Physics.}

John N. Bahcall; Frank Calaprice; Arthur B. McDonald; Yoji Totsuka

1996-01-01

329

Cytotoxicity Testing: Cell Experiments  

NASA Astrophysics Data System (ADS)

Screening for new anticancer agents has traditionally been done with in vitro cell culture methods. Even in the genomic era of target-driven drug design, screening for cytotoxic activity is still a standard tool in the search for new anticancer agents, especially if the mode of action of a substance is not yet known. A wide variety of cell culture methods with unique end-points are available for testing the anticancer potential of a substance. Each has its advantages and disadvantages, which must be weighed in the decision to use a particular method. Often several complementary methods are used to gain information on the mode of action of a substance.

Grünert, Renate; Westendorf, Aron; Buczkowska, Magdalena; Hänsch, Mareike; Grüunert, Sybil; Bednarski, Patrick J.

330

Developing an Advanced Module for Back-Contact Solar Cells  

Microsoft Academic Search

This paper proposes a novel concept for integrating ultrathin solar cells into modules. It is conceived as a method for fabricating solar panels starting from back-contact crystalline silicon solar cells. However, compared to the current state of the art in module manufacturing for back-contact solar cells, this novel concept aims at improvements in performance, reliability, and cost through the use

Jonathan Govaerts; Jo Robbelein; Mario Gonzalez; Ivan Gordon; Kris Baert; Ingrid De Wolf; Frederick Bossuyt; Steven Van Put; Jan Vanfleteren

2011-01-01

331

Third Working Meeting on Gallium Arsenide Solar Cells  

NASA Technical Reports Server (NTRS)

Research results are reported for GaAs Schottky barrier solar cells, GaAlAs/GaAs heteroface solar cells, and GaAlAs graded band gap solar cells. Related materials studies are presented. A systems study for GaAs and Si solar concentrator systems is given.

Walker, G. H. (compiler)

1976-01-01

332

Solar cell radiation handbook. [Degradation of solar cells in space radiation environment  

Microsoft Academic Search

The purpose of this document is to detail a method of predicting the degradation of a solar array in a space radiation environment. The text contains a discussion of solar cell technology which emphasizes the cell parameters which degrade in a radiation environment. The experimental techniques used in the evaluation of radiation effects are discussed. The theoretical aspects of radiation

H. Y. Tada; J. R. Jr. Carter

1977-01-01

333

Performance measurement of dye-sensitized solar cells and organic polymer solar cells  

Microsoft Academic Search

Performance characterization of the dye-sensitized solar cells (DSC) and organic polymer solar cells (OSC) has been investigated, in order to clarify how to accurately determine their performance. Accurate characterization of DSC requires consideration on the very slow temporal response, and variation of the quantum efficiency spectrum for the bias light. The I-V curves of the DSC are clearly dependent on

Yoshihiro Hishikawa

2008-01-01

334

Advanced Modelling of Silicon Wafer Solar Cells  

NASA Astrophysics Data System (ADS)

Modelling of solar cells today is general practice in research and widely-used in industry. Established modelling software is typically limited to one dimension and/or to small scales. Additionally, novel effects, like, e.g., the use of diffractive structures or luminescent materials, are not established. In this paper we discuss how the combination of different modelling techniques can be used to overcome these limitations. In this context two examples are presented. The first example concerns the combination of the open source simulation software PC1D with circuit modelling to investigate the effect of local shunts on the global characteristics of a silicon wafer solar cell. For the investigated example (4.5 cm2 cell area) we find that a local point shunt reduces the solar cell efficiency by 4% relative. The second example concerns the modelling of diffractive gratings for thin silicon wafer solar cells. For this purpose, we use the rigorous coupled wave analysis to simulate Sentaurus technical computer-aided design (TCAD) is combined with the rigorous coupled wave analysis, a method to solve Maxwell's equations for periodic structures. Here we show that a grating can be used to improve the absorption in a thin silicon wafer solar cell considerably.

Peters, Marius; Fajun, Ma; Siyu, Guo; Hoex, Bram; Blaesi, Benedikt; Glunz, Stefan; Aberle, Armin; Luther, Joachim

2012-10-01

335

Large area space solar cell assemblies  

NASA Technical Reports Server (NTRS)

Results of the development of a 34.3 sq cm space solar cell and integral glass cover are presented. Average AM(0) cell efficiency is 14 percent. The cell design includes a high performance back surface reflector yielding a thermal alpha of approximately 0.66. A novel process is described which integrates cell fabrication and encapsulation thereby achieving a reduction of encapsulation cost. Test results indicate the potential of this new technology.

Nowlan, M. J.; Spitzer, M. B.

1982-01-01

336

MIS silicon solar cells: potential advantages  

SciTech Connect

Recent progress with silicon solar cells based on the MIS or SIS structure is reviewed. To be competitive with pn junction technology in the near term, these cells must be much cheaper or have a higher efficiency in a production environment. Apparently, the minority carrier MIS cells have the greatest potential for large-scale applications. The data currently indicate that all types of MIS/SIS cells have some inherent instability problems.

Cheek, G.; Mertens, R.

1981-05-01

337

Plastic Schottky-barrier solar cells  

DOEpatents

A photovoltaic cell structure is fabricated from an active medium including an undoped polyacetylene, organic semiconductor. When a film of such material is in rectifying contact with a metallic area electrode, a Schottky-barrier junction is obtained within the body of the cell structure. Also, a gold overlayer passivates a magnesium layer on the undoped polyacetylene film. With the proper selection and location of elements a photovoltaic cell structure and solar cell are obtained.

Waldrop, J.R.; Cohen, M.J.

1981-12-30

338

Long-term radiation effects on GaAs solar cell characteristics  

Microsoft Academic Search

This report investigates preliminary design considerations which should be considered for a space experiment involving Gallium Arsenide (GaAs) solar cells. The electron radiation effects on GaAs solar cells were conducted in a laboratory environment, and a statistical analysis of the data is presented. In order to augment the limited laboratory data, a theoretical investigation of the effect of radiation on

J. H. Heinbockel; M. J. Doviak

1978-01-01

339

High voltage planar multijunction solar cell  

NASA Technical Reports Server (NTRS)

A high voltage multijunction solar cell is provided wherein a plurality of discrete voltage generating regions or unit cells are formed in a single generally planar semiconductor body. The unit cells are comprised of doped regions of opposite conductivity type separated by a gap or undiffused region. Metal contacts connect adjacent cells together in series so that the output voltages of the individual cells are additive. In some embodiments, doped field regions separated by a overlie the unit cells but the cells may be formed in both faces of the wafer.

Evans, J. C., Jr.; Chai, A. T.; Goradia, C. P. (inventors)

1982-01-01

340

Silicon solar cell process. Development, fabrication and analysis  

NASA Technical Reports Server (NTRS)

Solar cells were fabricated from unconventional silicon sheets, and the performances were characterized with an emphasis on statistical evaluation. A number of solar cell fabrication processes were used and conversion efficiency was measured under AMO condition at 25 C. Silso solar cells using standard processing showed an average efficiency of about 9.6%. Solar cells with back surface field process showed about the same efficiency as the cells from standard process. Solar cells from grain boundary passivation process did not show any improvements in solar cell performance.

Yoo, H. I.; Iles, P. A.; Tanner, D. P.

1978-01-01

341

Microstructural analysis of solar cell welds  

NASA Astrophysics Data System (ADS)

Parallel-gap resistance welding of silicon solar cells with copper interconnects results in complex microstructural variations that depend on the welding variables. At relatively low heat input solid-state welds are produced. At medium heat the Ag-Cu eutectic forms resulting in a braze joint. High heat produces a fusion weld with complete melting of the silver layer on the silicon solar cell. If the silicon is also melted, cracking occurs in the silicon cell below the weld nugget. These determinations were made using light microscopy, microprobe, and scanning electron microscopy analyses.

Moore, T. J.; Watson, G. K.; Baraona, C. R.

342

Radiation tests of SEP solar cells  

NASA Technical Reports Server (NTRS)

Solar cells specially designed for Solar Electric Propulsion (SEP) were tested with radiation fluences up to 10 to the 12th power protons having energies of 1.5, 1.0, and 0.5 MeV, and with fluences up to 10 to the 16th power electrons having 1.0 MeV energy. Spectrolab cells having a back-surface field were also irradiated with the same particles and fluences. Cell performances are described by curves in which normalized and absolute values of maximum power, maximum-power voltage, short-circuit current, and open-circuit voltage are plotted as a function of fluence.

Oman, H.

1977-01-01

343

Microstructural analysis of solar cell welds  

NASA Technical Reports Server (NTRS)

Parallel-gap resistance welding of silicon solar cells with copper interconnects results in complex microstructural variations that depend on the welding variables. At relatively low heat input solid-state welds are produced. At medium heat the Ag-Cu eutectic forms resulting in a braze joint. High heat produces a fusion weld with complete melting of the silver layer on the silicon solar cell. If the silicon is also melted, cracking occurs in the silicon cell below the weld nugget. These determinations were made using light microscopy, microprobe, and scanning electron microscopy analyses.

Moore, T. J.; Watson, G. K.; Baraona, C. R.

1982-01-01

344

Terrestrial solar spectra, solar simulation, and solar-cell-efficiency measurement  

SciTech Connect

After a discussion of the fundamentals of light transmittance, both measured and modeled atmospheric effects (i.e., air mass, molecular and aerosal scattering, and absorption) on terrestrial solar spectra are discussed. Geometric effects, such as global rather than direct beam measurements, and detector orientation are also reviewed. The SERI proposed ASTM global and direct beam terrestrial solar spectra are also presented. Then a detailed review/evaluation of the spectral characteristics of a number of solar simulators is given. Methods of calibrating the short circuit current of a solar cell with respect to a given irradiance spectrum are discussed. In conclusion, the need for a sophisticated solar simulator is proportional to the spectral mismatch between the spectral response of the reference cell used to set the solar simulator and that of the test cell. The report recommends using the recently proposed ASTM terrestrial solar irradiance spectrum as a reference spectrum and using either filtered xenon-arc or dichroic filtered tungsten-halogen (ENX or ELH) lamps for solar simulation.

Matson, R.; Bird, R.; Emery, K.

1981-09-01

345

Present status of solid state photoelectrochemical solar cells and dye sensitized solar cells using PEO-based polymer electrolytes  

Microsoft Academic Search

Due to energy crises in the future, much effort is being directed towards alternate sources. Solar energy is accepted as a novel substitute for conventional sources of energy. Out of the long list of various types of solar cells available on the market, solid state photoelectrochemical solar cells (SSPECs) and dye sensitized solar cells (DSSCs) are proposed as an alternative

Pramod Kumar Singh; R K Nagarale; S P Pandey; H W Rhee; Bhaskar Bhattacharya

2011-01-01

346

Flexible implementation of rigid solar cell technologies  

Microsoft Academic Search

As a source of clean, remote energy, photovoltaic (PV) systems are an important area of research. The majority of solar cells are rigid materials with negligible flexibility. Flexible PV systems possess many advantages, such as being transportable and incorporable on diverse structures. Amorphous silicon and organic PV systems are flexible; however, they lack the efficiency and lifetime of rigid cells.

Hollowell; Andrew E

2010-01-01

347

Large area space solar cell assemblies  

NASA Technical Reports Server (NTRS)

Development of a large area space solar cell assembly is presented. The assembly consists of an ion implanted silicon cell and glass cover. The important attributes of fabrication are (1) use of a back surface field which is compatible with a back surface reflector, and (2) integration of coverglass application and call fabrication.

Spitzer, M. B.; Nowlan, M. J.

1982-01-01

348

Method of restoring degraded solar cells  

DOEpatents

Amorphous silicon solar cells have been shown to have efficiencies which degrade as a result of long exposure to light. Annealing such cells in air at a temperature of about 200.degree. C. for at least 30 minutes restores their efficiency.

Staebler, David L. (Lawrenceville, NJ)

1983-01-01

349

High-efficiency concentrator silicon solar cells  

NASA Astrophysics Data System (ADS)

This report presents results from extensive process development in high-efficiency Si solar cells. An advanced design for a 1.56-cm(sup 2) cell with front grids achieved 26 percent efficiency at 90 suns. This is especially significant since this cell does not require a prismatic cover glass. New designs for simplified backside-contact solar cells were advanced from a status of near-nonfunctionality to demonstrated 21 to 22 percent for one-sun cells in sizes up to 37.5 cm(sup 2). An efficiency of 26 percent was achieved for similar 0.64-cm(sup 2) concentrator cells at 150 suns. More fundamental work on dopant-diffused regions is also presented here. The recombination vs. various process and physical parameters was studied in detail for boron and phosphorous diffusions. Emitter-design studies based solidly upon these new data indicate the performance vs. design parameters for a variety of the cases of most interest to solar cell designers. Extractions of p-type bandgap narrowing and the surface recombination for p- and n-type regions from these studies have a generality that extends beyond solar cells into basic device modeling.

Sinton, R. A.; Cuevas, A.; King, R. R.; Swanson, R. M.

1990-11-01

350

Computer modelling of inversion layer solar cells  

Microsoft Academic Search

A model has been developed which is capable of fast, yet accurate and versatile simulation of inversion layer solar cells. Operating temperature, substrate doping, light intensity, grid geometry, cell thickness, and other parameters can be readily varied to determine their effect on collection current, output voltage, fill factor, and conversion efficiency. The model is intended to be used to study

C. E. Norman; R. E. Thomas

1978-01-01

351

High-efficiency concentrator silicon solar cells  

SciTech Connect

This report presents results from extensive process development in high-efficiency Si solar cells. An advanced design for a 1.56-cm{sup 2} cell with front grids achieved 26% efficiency at 90 suns. This is especially significant since this cell does not require a prismatic cover glass. New designs for simplified backside-contact solar cells were advanced from a status of near-nonfunctionality to demonstrated 21--22% for one-sun cells in sizes up to 37.5 cm{sup 2}. An efficiency of 26% was achieved for similar 0.64-cm{sup 2} concentrator cells at 150 suns. More fundamental work on dopant-diffused regions is also presented here. The recombination vs. various process and physical parameters was studied in detail for boron and phosphorous diffusions. Emitter-design studies based solidly upon these new data indicate the performance vs design parameters for a variety of the cases of most interest to solar cell designers. Extractions of p-type bandgap narrowing and the surface recombination for p- and n-type regions from these studies have a generality that extends beyond solar cells into basic device modeling. 68 refs., 50 figs.

Sinton, R.A.; Cuevas, A.; King, R.R.; Swanson, R.M. (Stanford Univ., CA (USA). Solid-State Electronics Lab.)

1990-11-01

352

Walking-Beam Solar-Cell Conveyor  

NASA Technical Reports Server (NTRS)

Microprocessor-controlled walking-beam conveyor moves cells between work stations in automated assembly line. Conveyor has arm at each work station. In unison arms pick up all solar cells and advance them one station; then beam retracks to be in position for next step. Microprocessor sets beam stroke, speed, and position.

Feder, H.; Frasch, W.

1982-01-01

353

Mechanically stacked concentrator tandem solar cells  

NASA Technical Reports Server (NTRS)

Four-terminal mechanically stacked solar cells were developed for advanced space arrays with line-focus reflective concentrators. The top cells are based on AlGaAs/GaAs multilayer heterostructures prepared by low temperature liquid phase epitaxy. The bottom cells are based on heteroepitaxial InP/InGaAs liquid phase epitaxy or on homo-junction GaSb, Zn-diffused structures. The sum of the highest reached efficiencies of the top and bottom cells is 29.4 percent. The best four-terminal tandems have an efficiency of 27 to 28 percent. Solar cells were irradiated with 1 MeV electrons and their performances were determined as a function of fluence up to 10(exp 16) cm(exp-2). It was shown that the radiation resistance of developed tandem cells is similar to the most radiative stable AlGaAs/GaAs cells with a thin p-GaAs photoactive layer.

Andreev, V. M.; Rumyantsev, V. D.; Karlina, L. B.; Kazantsev, A. B.; Khvostikov, V. P.; Shvarts, M. Z.; Sorokina, S. V.

1995-01-01

354

Calculation of Optimally Reliable Solar Cell Arrays  

Microsoft Academic Search

Present state-of-the-art emphasis has been placed on the use of silicon solar cells interconnected in series-parallel groups to form a solar array providing basic power for long lifetime spacecraft (perhaps greater than 3 months). To assure that sufficient power will be available to operate equipments during the specified mission time, a reasonable margin must be designed into an array to

R. Brenan; F. Mason

1964-01-01

355

Hypervelocity Impact Testing of Space Station Freedom Solar Cells  

NASA Technical Reports Server (NTRS)

Solar array coupons designed for the Space Station Freedom electrical power system were subjected to hypervelocity impacts using the HYPER facility in the Space Power Institute at Auburn University and the Meteoroid/Orbital Debris Simulation Facility in the Materials and Processes Laboratory at the NASA Marshall Space Flight Center. At Auburn, the solar cells and array blanket materials received several hundred impacts from particles in the micron to 100 micron range with velocities typically ranging from 4.5 to 10.5 km/s. This fluence of particles greatly exceeds what the actual components will experience in low earth orbit. These impacts damaged less than one percent of total area of the solar cells and most of the damage was limited to the cover glass. There was no measurable loss of electrical performance. Impacts on the array blanket materials produced even less damage and the blanket materials proved to be an effective shield for the back surface of the solar cells. Using the light gas gun at MSFC, one cell of a four cell coupon was impacted by a 1/4 inch spherical aluminum projectile with a velocity of about 7 km/s. The impact created a neat hole about 3/8 inch in diameter. The cell and coupon were still functional after impact.

Christie, Robert J.; Best, Steve R.; Myhre, Craig A.

1994-01-01

356

Printable CIGS thin film solar cells  

NASA Astrophysics Data System (ADS)

Among the various thin film solar cells in the market, CuInGaSe thin film solar cells have been considered as the most promising alternatives to crystalline silicon solar cells because of their high photo-electricity conversion efficiency, reliability, and stability. However, many fabrication methods of CIGS thin film are based on vacuum processes such as evaporation and sputtering techniques which are not cost efficient. This work develops a solution method using paste or ink liquid spin-coated on glass that would be competitive to conventional ways in terms of cost effective, non-vacuum needed, and quick processing. A mixture precursor was prepared by dissolving appropriate amounts of composition chemicals. After the mixture solution was cooled, a viscous paste was prepared and ready for spin-coating process. A slight bluish CIG thin film on substrate was then put in a tube furnace with evaporation of metal Se followed by depositing CdS layer and ZnO nanoparticle thin film coating to complete a solar cell fabrication. Structure, absorption spectrum, and photo-electricity conversion efficiency for the as-grown CIGS thin film solar cell are under study.

Fan, Xiaojuan

2013-03-01

357

CAST - A CERN Experiment to Search for Solar Axions  

SciTech Connect

The CAST experiment at CERN is the only running solar axion telescope. The first results obtained so far with CAST - PHASE I is presented, which compete with the best astrophysically derived limits of the axion-to-photon coupling. The ongoing PHASE II of the experiment as well as the scheduled upgrades, which improve the axion discovery potential of CAST, are discussed.

Arik, E.; Boydag, F. S.; Cetin, S. A.; Dogan, O. B.; Hikmet, I. [Dogus University, Istanbul (Turkey); Aune, S.; Dafni, T.; Ferrer-Ribas, E.; Giomataris, I. [DAPNIA, Centre d'Etudes Nucleaires de Saclay (CEA-Saclay), Gif-sur-Yvette (France); Autiero, D.; Barth, K.; Davenport, M.; Di Lella, L.; Lasseur, C.; Papaevangelou, T.; Placci, A.; Riege, H.; Stewart, L.; Walckiers, L. [European Organization for Nuclear Research (CERN), Geneve (Switzerland); Belov, A. [Institute for Nuclear Research (INR), Russian Academy of Sciences, Moscow (Russian Federation)] (and others)

2007-04-23

358

Telescience Operations with the Solar Array Module Plasma Interaction Experiment.  

National Technical Information Service (NTIS)

The Solar Array Module Plasma Interactions Experiment (SAMPIE) is a flight experiment that flew on the Space Shuttle Columbia (STS-62) in March 1994, as part of the OAST-2 mission. The overall objective of SAMPIE was to determine the adverse environmental...

L. W. Wald I. K. Bibyk

1995-01-01

359

Solar Constant (SOLCON) Experiment: Ground Support Equipment (GSE) software development  

NASA Technical Reports Server (NTRS)

The Solar Constant (SOLCON) Experiment, the objective of which is to determine the solar constant value and its variability, is scheduled for launch as part of the Space Shuttle/Atmospheric Laboratory for Application and Science (ATLAS) spacelab mission. The Ground Support Equipment (GSE) software was developed to monitor and analyze the SOLCON telemetry data during flight and to test the instrument on the ground. The design and development of the GSE software are discussed. The SOLCON instrument was tested during Davos International Solar Intercomparison, 1989 and the SOLCON data collected during the tests are analyzed to study the behavior of the instrument.

Gibson, M. Alan; Thomas, Susan; Wilson, Robert

1991-01-01

360

Development of a large area space solar cell assembly  

NASA Technical Reports Server (NTRS)

The development of a large area high efficiency solar cell assembly is described. The assembly consists of an ion implanted silicon solar cell and glass cover. The important attributes of fabrication are the use of a back surface field which is compatible with a back surface reflector, and integration of coverglass application and cell fabrications. Cell development experiments concerned optimization of ion implantation processing of 2 ohm-cm boron-doped silicon. Process parameters were selected based on these experiments and cells with area of 34.3 sq cm wre fabricated. The average AMO efficiency of the twenty-five best cells was 13.9% and the best bell had an efficiency of 14.4%. An important innovation in cell encapsulation was also developed. In this technique, the coverglass is applied before the cell is sawed to final size. The coverglass and cell are then sawed as a unit. In this way, the cost of the coverglass is reduced, since the tolerance on glass size is relaxed, and costly coverglass/cell alignment procedures are eliminated. Adhesive investigated were EVA, FEP-Teflon sheet and DC 93-500. Details of processing and results are reported.

Spitzer, M. B.

1982-01-01

361

Method of fabricating a solar cell array  

SciTech Connect

A first set of pre-tabbed solar cells are assembled in a predetermined array with at least part of each tab facing upward, each tab being fixed to a bonding pad on one cell and abutting a bonding pad on an adjacent cell. The cells are held in place with a first vacuum support. The array is then inverted onto a second vacuum support which holds the tabs firmly against the cell pads they abut. The cells are exposed to radiation to melt and reflow the solder pads for bonding the tab portions not already fixed to bonding pads to these pads.

Coyle, P.J.; Crouthamel, M.S.; Lazzery, A.G.

1982-12-21

362

The Baksan gallium solar neutrino experiment  

SciTech Connect

A radiochemical /sup 71/Ga-/sup 71/Ge experiment to determine the integral flux of neutrinos from the sun has been constructed at the Baksan Neutrino Observatory in the USSR. Measurements have begun with 30 tonnes of gallium. The experiment is being expanded with the addition of another 30 tonnes. The motivation, experimental procedures, and present status of this experiment are presented. 43 refs., 1 fig., 1 tab.

Gavrin, V.N.; Abazov, A.I.; Abdurashitov, D.N.; Anosov, O.L.; Bychuk, O.V.; Danshin, S.N.; Eroshkina, L.A.; Faizov, E.L.; Gayevsky, V.I.; Girin, S.V.

1989-01-01

363

Plasmonic ITO-free polymer solar cell.  

PubMed

The aluminum and sliver multilayered nano-grating structure is fabricated by laser interference lithography and the intervals between nanoslits is filled with modified PEDOT:PSS. The grating structured transparent electrode functions as the anti-reflection layer which not only decreases the reflected light but also increases the absorption of the active layer. The performances of P3HT:PC61BM solar cells are studied experimentally and theoretically in detail. The field intensities of the transverse magnetic (TM) and transverse electrical (TE) waves distributed in the active layer are simulated by rigorous coupled wave analysis (RCWA). The power conversion efficiency of the plasmonic ITO-free polymer solar cell can reach 3.64% which is higher than ITO based polymer solar cell with efficiency of 3.45%. PMID:24922253

Lin, Ming-Yi; Kang, Yu Ling; Chen, Yu-Cheng; Tsai, Tsung-Han; Lin, Shih-Chieh; Huang, Yi-Hsiang; Chen, Yi-Jiun; Lu, Chun-Yang; Lin, Hoang Yan; Wang, Lon A; Wu, Chung-Chih; Lee, Si-Chen

2014-03-10

364

Cutting carbon nanotubes for solar cell application  

NASA Astrophysics Data System (ADS)

This paper presents the application of cutting multiwalled carbon nanotubes (cut-MWNTs) in solar cell. Cutting of MWNTs is performed by plasma fluorination and followed by defluorination. Cut-MWNTs with lengths of 50-200 nm are incorporated in a poly(3-octylthiophene)/n-Si heterojunction solar cell. We found that a device fabricated with cut-MWNTs shows much better performance than that of a device with pristine MWNTs. The device with cut-MWNTs shows short circuit current density, open circuit voltage, fill factor, and power conversion efficiency as 7.65 mA/cm2, 0.23 V, 31%, and 0.54%, respectively. Here, we proposed that cut-MWNTs provide efficient hole transportation having a few nanometer transportation path, hence suppressing recombination. Cut-MWNTs can be the solution to the shorting and shunting effects generally observed in the MWNT solar cell.

Kalita, Golap; Adhikari, Sudip; Aryal, Hare Ram; Umeno, Masayoshi; Afre, Rakesh; Soga, Tetsuo; Sharon, Maheshwar

2008-03-01

365

Cheap and efficient plasmonic solar cell  

NASA Astrophysics Data System (ADS)

Plasmonic solar cell is a very promising structure for high efficient solar cell application. It has some unique characteristics that allow high energy localization and higher solar energy absorption. Most of the proposed designs are based on using noble metals such as gold and silver to achieve the plasmonic effect. These metals are, however, expensive and increase the cost of the solar cell. Thus, the need to propose novel and cheap material with plasmonic like effect is of prime importance. In this work we demonstrate the applications of TiN that has good plasmonic like effect over wide bandwidth. A detailed comparative study of TiN and silver in an optimized design is presented, and we report comparable TiN field localization and light scattering effects. In addition, TiN is more compatible with the CMOS fabrication technology than the conventional plasmonic metals, which can even ease the integration with other optoelectric devices. Should the electrical performance be further studied and optimized, the overall efficiency of the solar cell can be maintained and/or enhanced and total cost/watt dramatically reduced.

Khalifa, Ahmed E.; Swillam, Mohamed A.

2014-03-01

366

Space solar cell research - Problems and potential  

NASA Technical Reports Server (NTRS)

The value of a passive, maintenance-free, renewable energy source was immediately recognized in the early days of the space program, and the silicon solar cell, despite its infancy, was quickly pressed into service. Efficiencies of those early space solar arrays were low, and lifetimes shorter than hoped for, but within a decade significant advances had been made in both areas. Better performance was achieved because of a variety of factors, ranging from improvements in silicon single crystal material, to better device designs, to a better understanding of the factors that affect the performance of a solar cell in space. Chief among the latter, particularly for the mid-to-high altitude (HEO) and geosynchronous (GEO) orbits, are the effects of the naturally occurring particulate radiation environment. Although not as broadly important to the photovoltaic community at large as increased efficiency, the topic of radiation damage is critically important to use of solar cells in space, and is a major component of the NASA research program in space photovoltaics. This paper will give a brief overview of some of the opportunities and challenges for space photovoltaic applications, and will discuss some of the current reseach directed at achieving high efficiency and controlling the effects of radiation damage in space solar cells.

Flood, Dennis J.

1986-01-01

367

Self-reconfiguring solar cell system  

NASA Technical Reports Server (NTRS)

A self-reconfiguring solar cell array is disclosed wherein some of the cells are switched so that they can be either in series or in shunt within the array. This feature of series or parallel switching of cells allows the array to match the load to achieve maximum power transfer. Automatic control is used to determine the conditions for maximum power operation and to switch the array into the appropriate configuration necessary to transfer maximum power to the load.

Gruber, R. P. (inventor)

1979-01-01

368

One-sun silicon solar cell research  

Microsoft Academic Search

This report describes research for the period September 1988 to February 1990 directed at improving the performance of crystalline and polycrystalline silicon solar cells. Key results include the demonstration of 24.2 percent energy conversion efficiency for 4-sq cm crystalline cells fabricated using the development of the Passivated Emitter Cell processing sequence, the demonstration of energy conversion efficiency up to 22.4

M. A. Green; J. Zhao; A. Wang; A. W. Blakers; A. M. Milne; X. Dai; C. M. Chong; S. R. Wenham; F. Zhang; F. Yun; J. Zolper; S. Narayanan; A. B. Sproul

1991-01-01

369

Physics based simulation of dye solar cells  

Microsoft Academic Search

Dye sensitized solar cells are interesting candidates for providing a renewable, cost efficient energy source with low environmental\\u000a impact. The lack of a suitable simulation software to study basic cell properties and to optimize the cell topology is currently\\u000a one of the factors hindering their commercialization. We present in this paper a theoretical model of the entire device based\\u000a on

M. Auf der Maur; A. Gagliardi; A. Di Carlo

370

High efficiency wraparound contact solar cells /HEWACS/  

NASA Technical Reports Server (NTRS)

A cell technology, producing high efficiency wrap-around contact solar cells (HEWACS), with both electrical contacts on the back and AMO conversion efficiencies of almost 15%, is presented. A flow chart indicating the baseline process sequence along with the process changes is given. Tests checking for coating delamination and contact integrity, those measuring contact strength, and thermal cycle tests, successfully demonstrated that this cell technology is ready to be moved to the pilot production stage.

Gillanders, M.; Opjorden, R.

1980-01-01

371

InP concentrator solar cells  

Microsoft Academic Search

The design, fabrication, and characterization of high-performance, n+\\/p InP shallow-homojunction (SHJ) concentrator solar cells are described. The InP device structures were grown by atmospheric-pressure metalorganic vapor phase epitaxy (APMOVPE). A preliminary assessment of the effects of grid collection distance and emitter sheet resistance on cell performance is presented. At concentration ratios of around 100, cells with efficiencies of 21.4% AM0

J. S. Ward; M. W. Wanlass; T. J. Coutts; K. A. Emery; C. R. Osterwald

1991-01-01

372

InP concentrator solar cells  

Microsoft Academic Search

The design, fabrication, and characterization of high-performance, n(+)\\/p InP shallow-homojunction (SHJ) concentrator solar cells are described. The InP device structures were grown by atmospheric-pressure metalorganic vapor phase epitaxy. A preliminary assessment of the effects of grid-collection distance and emitter-sheet resistance on cell performance is presented. At concentration ratios of around 100, cells with efficiencies of 21.4 percent AM0 (24.3 percent

J. S. Ward; M. W. Wanlass; T. J. Coutts; K. A. Emery; C. R. Osterwald

1991-01-01

373

Large area monolithic organic solar cells  

NASA Astrophysics Data System (ADS)

Although efficiencies of > 10% have recently been achieved in laboratory-scale organic solar cells, these competitive performance figures are yet to be translated to large active areas and geometries relevant for viable manufacturing. One of the factors hindering scale-up is a lack of knowledge of device physics at the sub-module level, particularly cell architecture, electrode geometry and current collection pathways. A more in depth understanding of how photocurrent and photovoltage extraction can be optimised over large active areas is urgently needed. Another key factor suppressing conversion efficiencies in large area cells is the relatively high sheet resistance of the transparent conducting anode - typically indium tin oxide. Hence, to replace ITO with alternative transparent conducting anodes is also a high priority on the pathway to viable module-level organic solar cells. In our paper we will focus on large area devices relevant to sub-module scales - 5 cm × 5 cm monolithic geometry. We have applied a range of experimental techniques to create a more comprehensive understanding of the true device physics that could help make large area, monolithic organic solar cells more viable. By employing this knowledge, a novel transparent anode consisting of molybdenum oxide (MoOx) and silver (Ag) is developed to replace ITO and PEDOT-free large area solar cell sub-modules, acting as both a transparent window and hole-collecting electrode. The proposed architecture and anode materials are well suited to high throughput, low cost all-solution processing.

Jin, Hui; Tao, Cheng; Hambsch, Mike; Pivrikas, Almantas; Velusamy, Marappan; Aljada, Muhsen; Zhang, Yuliang; Burn, Paul L.; Meredith, Paul

2012-11-01

374

Temperature dependence of amorphous silicon solar cell PV parameters  

Microsoft Academic Search

The temperature behavior of amorphous silicon (a-Si) based solar cells was measured for cells made under different fabrication conditions and with different thermal and illumination histories. Amorphous silicon solar cells exhibit a complex temperature behavior that depends on processing history and cannot be characterized by a unique temperature coefficient as in the case of crystalline silicon solar cells. In general,

D. E. Carlson; G. Lin; G. Ganguly

2000-01-01

375

A review of high-efficiency silicon solar cells  

NASA Technical Reports Server (NTRS)

Various parameters that affect solar cell efficiency were discussed. It is not understood why solar cells produced from less expensive Czochralski (Cz) silicon are less efficient than cells fabricated from more expensive float-zone (Fz) silicon. Performance characteristics were presented for recently produced, high-efficient solar cells fabricated by Westinghouse Electric Corp., Spire Corp., University of New South Wales, and Stanford University.

Rohatgi, A.

1986-01-01

376

LEO effects on candidate solar cell cover materials  

NASA Technical Reports Server (NTRS)

The Long Duration Exposure Facility (LDEF) test samples discussed within are part of the Solar Array Materials Passive (SAMPLE) LDEF experiment, which included contributions from NASA and Jet Propulsion Lab (JPL). Only the JPL portion is described in this paper. The JPL test plate contains 30 individual thin silicon solar cell/cover samples. It was the intent of the experiment to evaluate the stability and protective capability of various cover materials such as conventional fused silica and potential alternative materials such as Teflon, silicone RTV's, glass resins, polyimides, and a copolymer encapsulate. Examination of the recovered experiment shows extensive physical changes have occurred. Approximately 150 micrometeoroid/debris impact were noted, some directly on the solar cells. Of particular interest are the results of ultraviolet and atomic oxygen interactions with the various cover materials. Initial results show that the fused silica cover is the most stable and protective, with performance of other materials varying widely. Electrical measurements of the cell/cover samples are presented as part of the evaluation of cover materials to protect cells in low earth orbit environments.

Stella, Paul M.

1992-01-01

377

Solar cell having improved back surface reflector  

NASA Technical Reports Server (NTRS)

The operating temperature is reduced and the output of a solar cell is increased by using a solar cell which carries electrodes in a grid finger pattern on its back surface. These electrodes are sintered at the proper temperature to provide good ohmic contact. After sintering, a reflective material is deposited on the back surface by vacuum evaporation. Thus, the application of the back surface reflector is separate from the back contact formation. Back surface reflectors formed in conjunction with separate grid finger configuration back contacts are more effective than those formed by full back metallization of the reflector material.

Chai, A. T. (inventor)

1982-01-01

378

Solar cell array with lightweight support structure  

SciTech Connect

A panel comprising an aluminum honeycomb core and outer face skins of Kevlar, a bi-directional epoxy-reinforced polyparabenzamide fabric which is a thermal and electrical insulator adhering to the core and forming the opposite flat surfaces of the panel. Solar cells are glued directly to one face skin while a set of epoxy-reinforced carbon fiber stiffeners are glued to the other face skin. The composite structure has a coefficient of thermal expansion closely matching that of the solar cells providing a very lightweight and stiff structure.

Gounder, R.N.

1983-07-19

379

Solar cell contact formation using laser ablation  

SciTech Connect

The formation of solar cell contacts using a laser is described. A method of fabricating a back-contact solar cell includes forming a poly-crystalline material layer above a single-crystalline substrate. The method also includes forming a dielectric material stack above the poly-crystalline material layer. The method also includes forming, by laser ablation, a plurality of contacts holes in the dielectric material stack, each of the contact holes exposing a portion of the poly-crystalline material layer; and forming conductive contacts in the plurality of contact holes.

Harley, Gabriel; Smith, David; Cousins, Peter

2012-12-04

380

Comprehensive Silicon-Solar-Cell Program  

NASA Technical Reports Server (NTRS)

Comprehensive Silicon Solar Cell Computer Modeling (SICELL) program simulates silicon solar cell. Predicts device parameters as efficiency, voltage-vs.-current characteristic fill factor, and temperature coefficients of parameters. Technique used similar to numerical-integration methods, but commonality described by use of mesh-point field. Validation studies show accuracies of simulations range from 0.08 percent to 3.6 percent for 27 experimental data points over temperature range of 300K to 421K. Results obtained by use of 10 mesh points in n- and p-type regions and for two iterations. SICELL runs interactively on VAX computer under VMS and written in VAX/VMS FORTRAN 77.

Lamorte, Michael F.; Yeager, William M.

1989-01-01

381

Solar recharging system for hearing aid cells.  

PubMed

We present a solar recharging system for nickel-cadmium cells of interest in areas where batteries for hearing aids are difficult to obtain. The charger has sun cells at the top. Luminous energy is converted into electrical energy, during the day and also at night if there is moonlight. The cost of the charger and hearing aid is very low at 35 US$. The use of solar recharging for hearing aids would be useful in alleviating the problems of deafness in parts of developing countries where there is no electricity. PMID:7964140

Gòmez Estancona, N; Tena, A G; Torca, J; Urruticoechea, L; Muñiz, L; Aristimuño, D; Unanue, J M; Torca, J; Urruticoechea, A

1994-09-01

382

Cost competitiveness of a solar cell array power source for ATS-6 educational TV terminal  

NASA Technical Reports Server (NTRS)

A cost comparison is made between a terrestrial solar cell array power system and a variety of other power sources for the ATS-6 Satellite Instructional Television Experiment (SITE) TV terminals in India. The solar array system was sized for a typical Indian location, Lahore. Based on present capital and fuel costs, the solar cell array power system is a close competitor to the least expensive alternate power system. A feasibility demonstration of a terrestrial solar cell array system powering an ATS-6 receiver terminal at Cleveland, Ohio is described.

Masters, R. M.

1975-01-01

383

Energy Conversion: Nano Solar Cell  

Microsoft Academic Search

Problems of fossil-fuel-induced climate change have sparked a demand for sustainable energy supply for all sectors of economy. Most laboratories continue to search for new materials and new technique to generate clean energy at affordable cost. Nanotechnology can play a major role in solving the energy problem. The prospect for solar energy using Si-based technology is not encouraging. Si photovoltaics

Muhammad Yahaya; Chi Chin Yap; Muhamad Mat Salleh

2009-01-01

384

LDEF (Postflight), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08  

NASA Technical Reports Server (NTRS)

LDEF (Postflight), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08 EL-1994-00147 LDEF (Postflight), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08 The post flight photograph was taken in the SAEF II at KSC prior to removal of the experiment tray from the LDEF and shows the Solar Array Materials Passive LDEF Experiment (SAMPLE) on the LDEF. Six (6) plates of passive components, provided by various experiment organizations and designated plate I thru plate VI, are shown mounted in a three (3) inch deep LDEF peripheral tray. All six plates are aluminum and attach to the LDEF experiment tray with non-magnetic stainless steel fasteners. Plate I, located in the upper right corner, consist of a combination of solar cells with and without covers, solar cell modules and solar arrays assembled on the baseplate. Three of the four solar arrays are missing. Other components appear to be secure. Plate II in the top center section, has twenty seven (27) composite samples, carbon fiber and glass fiber, mounted on the baseplate. The composites appear to be intact with no physical damage. Plate III, in the upper left corner, consist of metallized and thin polymeric films (Kapton, Mylar, TEFLON® , white Tedlar,etc.). The thin films without protective coatings sustained significant damage and most were destroyed. The thin film specimen hanging by one end in the flight photograph is missing. The metallized film apparently survived the mission with minimum damage. Plate IV located in the lower right corner consist of metals and coatings mounted in an aluminum baseplate and covered with a thin aluminum coverplate that partially mask the specimen. Several of the coatings appear to have darkened and a unique pattern of light brown discoloration appears around the outer edges of the mounting plate and along the lower edge of the coverplates. Plate V, in the lower center section, contained thermal plastics and structural film configured into tensile and shear specimen. All specimen, including the tape holding down the small specimen in the lower right corner, have darkened significantly during the extended time in space. Plate VI, in the lower left corner, is populated with solar cells and associated components such as covers, encapsulants,adhesives, etc. The solar cell components appear to be intact with no apparent physical damage.The colors of the specimen, however, appear to have darkened. The photographic lighting angle has significantly highlighted abrasions on the mounting plate surface.

1990-01-01

385

Gaalas/Gaas Solar Cell Process Study  

NASA Technical Reports Server (NTRS)

Available information on liquid phase, vapor phase (including chemical vapor deposition) and molecular beam epitaxy growth procedures that could be used to fabricate single crystal, heteroface, (AlGa) As/GaAs solar cells, for space applications is summarized. A comparison of the basic cost elements of the epitaxy growth processes shows that the current infinite melt LPE process has the lower cost per cell for an annual production rate of 10,000 cells. The metal organic chemical vapor deposition (MO-CVD) process has the potential for low cost production of solar cells but there is currently a significant uncertainty in process yield, i.e., the fraction of active material in the input gas stream that ends up in the cell. Additional work is needed to optimize and document the process parameters for the MO-CVD process.

Almgren, D. W.; Csigi, K. I.

1980-01-01

386

InP concentrator solar cells  

NASA Technical Reports Server (NTRS)

The design, fabrication, and characterization of high-performance, n(+)/p InP shallow-homojunction (SHJ) concentrator solar cells are described. The InP device structures were grown by atmospheric-pressure metalorganic vapor phase epitaxy. A preliminary assessment of the effects of grid-collection distance and emitter-sheet resistance on cell performance is presented. At concentration ratios of around 100, cells with efficiencies of 21.4 percent AM0 (24.3 percent direct) at 25 C are fabricated. These are the highest efficiencies yet reported for single-junction InP solar cells. The performance of these cells as a function of temperature is discussed, and areas for future improvement are outlined. Application of these results to other InP-based photovoltaic devices is discussed.

Ward, J. S.; Wanlass, M. W.; Coutts, T. J.; Emery, K. A.; Osterwald, C. R.

1991-01-01

387

NanoSense: Solar Cell Animation  

NSDL National Science Digital Library

This Flash animation depicts the function of two types of solar cell systems: a silicon-based cell and a dye-sensitized cell. Both systems convert light energy to electrical energy, but the structure is quite different. The silicon-based cell is a solid-state semiconductor that employs two crystalline silicon layers between metal conducting strips. The dye-sensitized cell consists of a layer of titanium dioxide nanoparticles bonded to a layer of organic dye, and immersed in an electrolyte solution. Both systems excite electrons, which are directed to conducting strips and flow through a wire as electric current.

2013-04-19

388

Development of economical improved thick film solar cell contact  

NASA Technical Reports Server (NTRS)

Metal screened electrodes were investigated with base metal pastes and silver systems being focused upon. Contact resistance measurements were refined. A facility allowing fixing in hydrogen and other atmospheres was acquired. Several experiments were made applying screenable pastes to solar cells. Doping investigations emphasized eutectic alloys reduced to powders. Metal systems were reviewed and base metal experiments were done with nickel and copper using lead and tin as the frit metals. Severe adhesion problems were experienced with hydrogen atmospheres in all metal systems. A two step firing schedule was devised. Aluminum-silicon and aluminum-germanium eutectic doping additions to copper pastes were tried on 2 1/4 in diameter solar cell back contacts, both with good results.

Ross, B.

1979-01-01

389

Burst annealing of high temperature GaAs solar cells  

NASA Technical Reports Server (NTRS)

One of the major limitations of solar cells in space power systems is their vulnerability to radiation damage. One solution to this problem is to periodically heat the cells to anneal the radiation damage. Annealing was demonstrated with silicon cells. The obstacle to annealing of GaAs cells was their susceptibility to thermal damage at the temperatures required to completely anneal the radiation damage. GaAs cells with high temperature contacts and encapsulation were developed. The cells tested are designed for concentrator use at 30 suns AMO. The circular active area is 2.5 mm in diameter for an area of 0.05 sq cm. Typical one sun AMO efficiency of these cells is over 18 percent. The cells were demonstrated to be resistant to damage after thermal excursions in excess of 600 C. This high temperature tolerance should allow these cells to survive the annealing of radiation damage. A limited set of experiments were devised to investigate the feasibility of annealing these high temperature cells. The effect of repeated cycles of electron and proton irradiation was tested. The damage mechanisms were analyzed. Limitations in annealing recovery suggested improvements in cell design for more complete recovery. These preliminary experiments also indicate the need for further study to isolate damage mechanisms. The primary objective of the experiments was to demonstrate and quantify the annealing behavior of high temperature GaAs cells. Secondary objectives were to measure the radiation degradation and to determine the effect of repeated irradiation and anneal cycles.

Brothers, P. R.; Horne, W. E.

1991-01-01

390

SAGE: Solar Neutrino Data from SAGE, the Russian-American Gallium Solar Neutrino Experiment  

DOE Data Explorer

SAGE is a solar neutrino experiment based on the reaction 71Ga + n goes to 71Ge + e-. The 71Ge atoms are chemically extracted from a 50-metric ton target of Ga metal and concentrated in a sample of germane gas mixed with xenon. The atoms are then individually counted by observing their decay back to 71Ga in a small proportional counter. The distinguishing feature of the experiment is its ability to detect the low-energy neutrinos from proton-proton fusion. These neutrinos, which are made in the primary reaction that provides the Sun's energy, are the major component of the solar neutrino flux and have not been observed in any other way. To shield the experiment from cosmic rays, it is located deep underground in a specially built facility at the Baksan Neutrino Observatory in the northern Caucasus mountains of Russia. Nearly 100 measurements of the solar neutrino flux have been made during 1990-2000, and their combined result is a neutrino capture rate that is well below the prediction of the Standard Solar Model. The significant suppression of the solar neutrino flux that SAGE and other solar neutrino experiments have observed gives a strong indication for the existence of neutrino oscillations. [copied from the SAGE homepage at http://ewi.npl.washington.edu/SAGE/SAGE.html

SAGE Collaboration

391

Modifying the solar spectrum to enhance silicon solar cell efficiency—An overview of available materials  

Microsoft Academic Search

There are three ways in which the cell efficiency of silicon solar cells may be improved by better exploitation of the solar spectrum: down-conversion (cutting one high energy photon into two low energy photons), photoluminescence (shifting photons into wavelength regions better accepted by the solar cell) and up-conversion (combining low energy photons to one high energy photon). In this paper,

C. Strümpel; M. McCann; G. Beaucarne; V. Arkhipov; A. Slaoui; V. Švr?ek; C. del Cañizo; I. Tobias

2007-01-01

392

Theoretical Quantification of Nonlinear Effects in Silicon Solar Cells.  

National Technical Information Service (NTIS)

An analytic model for the internal quantum efficiency of solar cells is presented. It is especially intended for explanation and quantitative analysis of nonlinear effects in silicon solar cells. The model differs from conventional ones in that it conside...

J. M. Ruiz

1986-01-01

393

Harmful Shunting Mechanisms Found in Silicon Solar Cells (Fact Sheet)  

SciTech Connect

Scientists developed near-field optical microscopy for imaging electrical breakdown in solar cells and identified critical electrical breakdown mechanisms operating in industrial silicon and epitaxial silicon solar cells.

Not Available

2011-05-01

394

High Rate Laser Pitting Technique for Solar Cell Texturing.  

National Technical Information Service (NTIS)

High rate laser pitting technique for solar cell texturing Efficiency of crystalline silicon solar cells can be improved by creating a texture on the surface to increase optical absorption. Different techniques have been developed for texturing, with the ...

H. J. Herfurth

2011-01-01

395

Polymer-fullerene bulk heterojunction solar cells  

NASA Astrophysics Data System (ADS)

Organic solar cells have the potential to be low-cost and efficient solar energy converters, with a promising energy balance. They are made of carbon-based semiconductors, which exhibit favourable light absorption and charge generation properties, and can be manufactured by low temperature processes such as printing from solvent-based inks, which are compatible with flexible plastic substrates or even paper. In this review, we will present an overview of the physical function of organic solar cells, their state-of-the-art performance and limitations, as well as novel concepts to achieve a better material stability and higher power conversion efficiencies. We will also briefly review processing and cost in view of the market potential.

Deibel, Carsten; Dyakonov, Vladimir

2010-09-01

396

High-performance silicon nanohole solar cells.  

PubMed

We demonstrate Si nanohole arrays as a superior sunlight-absorbing nanostructure for photovoltaic solar cell applications. Under 1 sun AM1.5G illumination, a Si nanohole solar cell with p-n junctions via P diffusion exhibited a open-circuit voltage of 566.6 mV, a short-circuit current density of 32.2 mA/cm(2), and a remarkable power conversion efficiency of 9.51%, which is higher than that of its counterparts based on Si nanowires, planar Si, and pyramid-textured Si. The nanohole array geometry presents a novel and viable method fo cost-efficient solar energy conversion. PMID:20426468

Peng, Kui-Qing; Wang, Xin; Li, Li; Wu, Xiao-Ling; Lee, Shuit-Tong

2010-05-26

397

Electrical overstress failure in silicon solar cells  

SciTech Connect

A solar-cell electrical-overstress-failure model and the results of experimental measurements of threshold pulsed failure currents on four types of silicon solar cells are presented. The transient EMP field surrounding a lightning stroke has been identified as a potential threat to a photovoltaic array, yet failure analysis of solar cells in a pulsed environment had not previously been reported. Failure in the low-resistivity concentrator cells at pulse widths between 1 ..mu..s and 1 ms occurred initially in the junction. Finger damage in the form of silver melting occurs at currents only slightly greater than that required for junction damage. The result of reverse-bias transient-overstress tests on high-resistivity (10 ..cap omega..cm) cells demonstrated that the predominant failure mode was due to edge currents. These flat-plate cells failed at currents of only 4 to 20 A, which is one or two orders of magnitude below the model predictions. It thus appears that high-resistivity flat-plate cells are quite vulnerable to electrical overstress which could be produced by a variety of mechanisms.

Pease, R.L.; Barnum, J.R.; van Lint, V.A.J.; Vulliet, W.V.; Wrobel, T.F.

1982-11-01

398

LDEF (Flight), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08  

NASA Technical Reports Server (NTRS)

LDEF (Flight), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08 EL-1994-00666 LDEF (Flight), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08 The flight photograph was taken from the Orbiter aft flight deck during the LDEF retrieval prior to berthing the LDEF in the Orbiter cargo bay and shows the Solar Array Materials Passive LDEF Experiment (SAMPLE) on the LDEF. Six (6) plates of passive components, provided by various experiment organizations and designated plate I thru plate VI, are shown mounted in a three (3) inch deep LDEF peripheral tray. All six plates are aluminum and attach to the LDEF experiment tray with non-magnetic stainless steel fasteners. Plate I, located in the upper left corner, consist of a combination of solar cells with and without covers, solar cell modules and solar arrays assembled on the baseplate. Two of the four solar arrays are missing and one appears to be attached at only one corner. Other components appear to be secure. Plate II in the left center section, has twenty-seven (27) composite samples, carbon fiber and glass fiber, mounted on the baseplate. The composites appear to be intact with no physical damage. Plate III, in the lower left corner, consist mostly of metallized and thin polymeric films (Kapton, Mylar, TEFLON® , white Tedlar,etc.). The thin films without protective coatings sustained significant damage and most were destroyed. The metallized film apparently survived with minimum damage. Plate IV located in the upper right corner consist of metals and coatings mounted in an aluminum baseplate and covered with a thin aluminum coverplate that partially mask the specimen. Several of the coatings appear to have changed to a darker color and a light brown discoloration appears around the outer edges of the mounting plate and along the right edge of the coverplates. Plate V, in the right center section, contained thermal plastics and structural film configured into tensile and shear specimen. All specimens, including the tape holding down the small specimen in the lower right corner, have darkened significantly during the extended time in space. Plate VI, in the lower right corner, is populated with solar cells and associated components such as covers, encapsulants,adhesives, etc.. The solar cell components appear to be intact with no apparent physical damage.The colors of the specimen, however, appear to have darkened.

1990-01-01

399

Luminescent solar concentrators and all-inorganic nanoparticle solar cells for solar energy harvesting  

NASA Astrophysics Data System (ADS)

Increasing energy demand and the parallel increase of greenhouse gas emissions are challenging researchers to find new and cleaner energy sources. Solar energy harvesting is arguably the most promising candidate for replacing fossil-fuel power generation. Photovoltaics are the most direct way of collecting solar energy; cost continues to hinder large-scale implementation of photovoltaics, however. Therefore, alternative technologies that will allow the extraction of solar power, while maintaining the overall costs of fabrication, installation, collection, and distribution low, must be explored. This thesis focuses on the fabrication and testing of two types of devices that step up to this challenge: the luminescent solar concentrator (LSC) and all-inorganic nanoparticle solar cells. In these devices I make use of novel materials, semiconducting polymers and inorganic nanoparticles, both of which have lower costs than the crystalline materials used in the fabrication of traditional photovoltaics. Furthermore, the cost of manufacturing LSCs and the nanoparticle solar cells is lower than the manufacturing cost of traditional optics-based concentrators and crystalline solar cells. An LSC is essentially a slab of luminescent material that acts as a planar light pipe. The LSC absorbs incoming photons and channels fluoresced photons toward appropriately located solar cells, which perform the photovoltaic conversion. By covering large areas with relatively inexpensive fluorescing organic dyes or semiconducting polymers, the area of solar cell needed is greatly reduced. Because semiconducting polymers and quantum dots may have small absorption/emission band overlaps, tunable absorption, and longer lifetimes, they are good candidates for LSC fabrication, promising improvement with respect to laser dyes traditionally used to fabricate LSCs. Here the efficiency of LSCs consisting of liquid solutions of semiconducting polymers encased in glass was measured and compared to the efficiency of LSCs based on small molecule laser dyes and on quantum dots. Factors affecting the optical efficiency of the system such as the luminescing properties of the fluorophors were examined. The experimental results were compared to Monte-Carlo simulations. Our results suggest that commercially available quantum dots cannot serve as viable LSC dyes because of large absorption/emission band overlap and relatively low quantum yield. Materials such as Red F demonstrate that semi-conducting polymers with high quantum yield and small absorption/emission band overlap are good candidates for LSCs. Recently, a solar cell system based purely on CdSe and Cite nanoparticles as the absorbing materials was proposed ans it was suggested that its operational mechanism was that of polymer donor/acceptor systems. Here we present solar cells consisting of a sintered active bilayer of CdSe and PbSe nanoparticles in the structure ITO/CdSe/interlayer/PbSe/Al, where an interlayer of LiF or Al2O3 was found necessary to prevent low shunt resistance from suppressing the photovoltaic behavior. We fabricated unoptimized solar cells with a short-circuit current of 6 mA/cm2, an open-circuit voltage of 0.18 V, and a fill factor of 41%. External quantum efficiency spectra revealed that photons from the infrared portion of the spectrum were not collected, suggesting that the low bandgap PbSe film did not contribute to the photocurrent of the structure despite exhibiting photoconductivity. Other measurements, however, showed that the PbSe film was indeed necessary to produce a photovoltage and transport electrons. Through sintering, the nanoparticle films acquired bandgaps similar to those of the corresponding bulk materials and became more conductive. Because the PbSe films were found to be considerably more conductive than the CdSe ones, we suggest that the PbSe layer is effectively behaving like a low conductivity electrical contact. Therefore, in contrast to the photovoltaics presented in the seminal research on CdSe/Cite solar cells, the CdSe/PbSe solar cell system presented here d

Sholin, Veronica

400

Modified genetic programming combining with particle swarm optimization and performance criterion in solar cell fabrication  

Microsoft Academic Search

This study describes the design and development of the novel model for the process optimization of solar cell fabrication.\\u000a The model performance can affect the result of the physical experiment in the solar cell fabrication because the high accuracy\\u000a model can provide the closer result to the output efficiency of the physical experiment. In this study, genetic programming\\u000a (GP) based

Hyeon Bae; Tae-Ryong Jeon; Sungshin Kim; Seung-Soo Han

2010-01-01

401

A Simple and Inexpensive Solar Energy Experiment.  

ERIC Educational Resources Information Center

An experiment is presented which utilizes the current solid state technology to demonstrate electrochemical generation of hydrogen gas, direct generation of electricity for pumping water, and energy conversion efficiency. The experimental module costs about $100 and can be used repeatedly. (BB)

Evans, J. H.; Pedersen, L. G.

1979-01-01

402

Glass sealed silicon membrane solar cell  

Microsoft Academic Search

An improved silicon back surface field solar cell is described comprising a high quality very thin silicon single crystal wafer base 0.0005 to about 0.0004 inch thick. The base contains a back surface field region of the same type, P or N, as the base. The back surface field region has a thickness of about 1 m and a dopant

Mandelkorn

1987-01-01

403

Low cost silicon solar cell array  

NASA Technical Reports Server (NTRS)

The technological options available for producing low cost silicon solar cell arrays were examined. A project value of approximately $250/sq m and $2/watt is projected, based on mass production capacity demand. Recommendations are included for the most promising cost reduction options.

Bartels, F. T. C.

1974-01-01

404

Metal electrode for amorphous silicon solar cells  

DOEpatents

An amorphous silicon solar cell having an N-type region wherein the contact to the N-type region is composed of a material having a work function of about 3.7 electron volts or less. Suitable materials include strontium, barium and magnesium and rare earth metals such as gadolinium and yttrium.

Williams, Richard (Princeton, NJ)

1983-01-01

405

Fluorescent window for liquid junction solar cells  

Microsoft Academic Search

To recover part of the often substantial fraction of the sunlight lost in practical semiconductor-liquid junction solar cells by solution absorption, two designs incorporating fluorescent windows are analyzed and tested. In these schemes the luminescers absorb incident light in regions of electrolyte absorption and re-emit at wavelengths both within the semiconductor band gap and the transparent range of the solution.

M. S. Kazacos; E. J. McHenry; A. Heller; B. Miller

1980-01-01

406

Large area Czochralski silicon for solar cells  

NASA Technical Reports Server (NTRS)

A detailed model of a typical Czochralski silicon crystal puller is utilized to predict maximum crystal growth rate as a function of various furnace parameters. Results of this analysis, when combined with multiblade slurry sawing, indicate that the Czochralski process is highly attractive for achieving near-term cost reduction of solar cell silicon.

Rea, S. N.; Wakefield, G. F.

1976-01-01

407

Screen printed interdigitated back contact solar cell  

NASA Technical Reports Server (NTRS)

Interdigitated back contact solar cells are made by screen printing dopant materials onto the back surface of a semiconductor substrate in a pair of interdigitated patterns. These dopant materials are then diffused into the substrate to form junctions having configurations corresponding to these patterns. Contacts having configurations which match the patterns are then applied over the junctions.

Baraona, C. R.; Mazaris, G. A.; Chai, A. T. (inventors)

1984-01-01

408

Progress in low cost solar cells  

Microsoft Academic Search

The solar cell is a remarkable device. It converts the sun's distributed energy into electricity with 15 to 20 percent efficiency, has no moving parts, is simple in structure and in the case of silicon is made of one of the most abundant elements on earth. Such a device would give a clean, quiet source of power and an alternative

P. Rappaport

1976-01-01

409

Prepolymer Syrup for Encapsulating Solar Cells  

NASA Technical Reports Server (NTRS)

Clear polymer syrup, made by disolving n-butyl acrylate prepolymer in monomer, used to encapsulate solar cells by any of three standard processes (dipping, multiple coating, or automated machine coating). Use of cyclohexane instead of methanol/water solvent during initial polymerization stage maintains high molecular weight and raises yield of linear polymer to essentially 100 percent.

Gupta, A.; Ingham, J. D.; Yavrouian, A. H.

1982-01-01

410

Fatigue Properties of Solar Cell Interconnectors.  

National Technical Information Service (NTIS)

A test rig was developed to evaluate the fatigue properties of molybdenum and silver mesh solar cell interconnectors at temperatures of -130 C and -170 C. The rig consists of an electromagnetic vibrator and a specimen clamping system and is operated using...

R. B. Evans S. Stevens P. Campbell

1977-01-01

411

Comprehensive solar cell modeling and correlation studies  

NASA Technical Reports Server (NTRS)

Modeling and correlation studies of solar cells was discussed. Recursive relationships were used to generate solutions at a number of mesh points within the emitter region. Photoexcited hole concentration and built-in electric field were calculated as a function of position. Simulated and experimentally determined I-V curves were shown to have good fit.

Lamorte, M. L.

1985-01-01

412

Texturing industrial multicrystalline silicon solar cells  

Microsoft Academic Search

Three potential techniques for texturing commercial multicrystalline silicon solar cells are compared on the basis of reflectance measurements. Wet acidic texturing, which would be the least costly to implement, produces a modest improvement in reflection before antireflection coating and encapsulation, whereas maskless reactive-ion etching texturing, and especially masked reactive-ion etched ‘pyramids’, generate a larger gain in absorption. After antireflection coating

D. H. Macdonald; A. Cuevas; M. J. Kerr; C. Samundsett; D. Ruby; S. Winderbaum; A. Leo

2004-01-01

413

Tandem junction amorphous silicon solar cells  

DOEpatents

An amorphous silicon solar cell has an active body with two or a series of layers of hydrogenated amorphous silicon arranged in a tandem stacked configuration with one optical path and electrically interconnected by a tunnel junction. The layers of hydrogenated amorphous silicon arranged in tandem configuration can have the same bandgap or differing bandgaps.

Hanak, Joseph J. (Lawrenceville, NJ)

1981-01-01

414

Hybrid silicon nanocone-polymer solar cells.  

PubMed

Recently, hybrid Si/organic solar cells have been studied for low-cost Si photovoltaic devices because the Schottky junction between the Si and organic material can be formed by solution processes at a low temperature. In this study, we demonstrate a hybrid solar cell composed of Si nanocones and conductive polymer. The optimal nanocone structure with an aspect ratio (height/diameter of a nanocone) less than two allowed for conformal polymer surface coverage via spin-coating while also providing both excellent antireflection and light trapping properties. The uniform heterojunction over the nanocones with enhanced light absorption resulted in a power conversion efficiency above 11%. Based on our simulation study, the optimal nanocone structures for a 10 ?m thick Si solar cell can achieve a short-circuit current density, up to 39.1 mA/cm(2), which is very close to the theoretical limit. With very thin material and inexpensive processing, hybrid Si nanocone/polymer solar cells are promising as an economically viable alternative energy solution. PMID:22545674

Jeong, Sangmoo; Garnett, Erik C; Wang, Shuang; Yu, Zongfu; Fan, Shanhui; Brongersma, Mark L; McGehee, Michael D; Cui, Yi

2012-06-13

415

Physics based simulation of dye solar cells  

Microsoft Academic Search

Dye sensitized solar cells (DSCs) are interesting candidates for providing a renewable, cost efficient energy source with low environmental impact. Although DSCs are very close to be commercialized, many issues still need to be addressed. Part of the problem is related to the lack of a reliable and consistent simulator able to catch the physics underlying the functioning of the

M. Auf der Maur; A. Gagliardi; A. Di Carlo

2010-01-01

416

Metalizing Solar Cells by Selective Electroplating  

NASA Technical Reports Server (NTRS)

Contact patterns traced by laser scanning. Conductor paths deposited on silicon solar-cell wafers by laser irradiation followed by electroplating. Laser-assisted metalization technique offers better resolution and lower contact resistance than does conventional metalization by screen printing. At the same time, less expensive than metalization with masks and photolithography.

Dutta, S.; Palaschak, P. A.

1986-01-01

417

Aluminum doping improves silicon solar cells  

NASA Technical Reports Server (NTRS)

Aluminum doped silicon solar cells with resistivities in the 10- to 20-ohm centimeter range have broad spectral response, high efficiency and long lifetimes in nuclear radiation environments. Production advantages include low material rejection and increased production yields, and close tolerance control.

1966-01-01

418

Assembly jig assures reliable solar cell modules  

NASA Technical Reports Server (NTRS)

Assembly jig holds the components for a solar cell module in place as the assembly is soldered and bonded by the even heat of an oven. The jig is designed to the configuration of the planned module. It eliminates uneven thermal conditions caused by hand soldering methods.

Ofarrell, H. O.

1966-01-01

419

Amorphous silicon nanocone array solar cell  

PubMed Central

In the hydrogenated amorphous silicon [a-Si:H]-thin film solar cell, large amounts of traps reduce the carrier's lifetime that limit the photovoltaic performance, especially the power conversion efficiency. The nanowire structure is proposed to solve the low efficiency problem. In this work, we propose an amorphous silicon [a-Si]-solar cell with a nanocone array structure were implemented by reactive-ion etching through a polystyrene nanosphere template. The amorphous-Si nanocone exhibits absorption coefficient around 5 × 105/cm which is similar to the planar a-Si:H layer in our study. The nanostructure could provide the efficient carrier collection. Owing to the better carrier collection efficiency, efficiency of a-Si solar cell was increased from 1.43% to 1.77% by adding the nanocone structure which has 24% enhancement. Further passivation of the a-Si:H surface by hydrogen plasma treatment and an additional 10-nm intrinsic-a-Si:H layer, the efficiency could further increase to 2.2%, which is 54% enhanced as compared to the planar solar cell. The input-photon-to-current conversion efficiency spectrum indicates the efficient carrier collection from 300 to 800 nm of incident light.

2012-01-01

420

Compensated amorphous-silicon solar cell  

Microsoft Academic Search

An amorphous silicon solar cell including an electrically conductive substrate, a layer of glow discharge deposited hydrogenated amorphous silicon having regions of differing conductivity with at least one region of intrinsic hydrogenated amorphous silicon. The layer of hydrogenated amorphous silicon has opposed first and second major surfaces where the first major surface contacts the elecrically conductive substrate and an electrode

Devaud

1982-01-01

421

High efficiency double sided solar cells.  

National Technical Information Service (NTIS)

Silicon technology state of the art for single crystalline was given to be limited to less than 20% efficiency. A proposed new form of photovoltaic solar cell of high current high efficiency with double sided structures has been given. The new forms could...

M. M. Seddik

1990-01-01

422

Computer modeling of high intensity solar cells  

Microsoft Academic Search

The purpose of this program is to provide general analytic support to Sandia National Laboratories' effort to develop high efficiency, high concentration solar cells. This report covers work performed between November 5, 1984, and December 31, 1985, and includes reprints of three papers presented at the 18th IEEE Photovoltaic Specialists' Conference. In the first paper, the factors that presently prevent

J. L. Gray; M. S. Lundstrom; R. J. Schwartz

1987-01-01

423

Concentrator Solar-Cell Flash Tester.  

National Technical Information Service (NTIS)

A method is described for testing solar cells at high concentrations in a laboratory environment without the need of coolant loops, precision tracking apparatus or dependence on cloud-free days. A complete Voltage-Current (V-I) characteristic curve for a ...

R. E. Hibray

1982-01-01

424

High-Temperature Solar Cell Development.  

National Technical Information Service (NTIS)

The vast majority of satellites and near-earth probes developed to date have relied upon photovoltaic power generation. If future missions to probe environments close to the sun will be able to use photovoltaic power, solar cells that can function at high...

G. A. Landis R. P. Raffaelle D. Merritt

2004-01-01

425

Silicon Solar Cell Development for Concentrator Applications.  

National Technical Information Service (NTIS)

The objective of this work is to optimize the design of, and to develop the fabrication process for single-crystal silicon solar cells for applications at illumination levels up to approximately 100 suns and operating temperatures up to approximately 100 ...

J. G. Fossum E. L. Burgess

1977-01-01

426

Studies of silicon pn junction solar cells  

NASA Technical Reports Server (NTRS)

Modifications of the basic Shockley equations that result from the random and nonrandom spatial variations of the chemical composition of a semiconductor were developed. These modifications underlie the existence of the extensive emitter recombination current that limits the voltage over the open circuit of solar cells. The measurement of parameters, series resistance and the base diffusion length is discussed. Two methods are presented for establishing the energy bandgap narrowing in the heavily-doped emitter region. Corrections that can be important in the application of one of these methods to small test cells are examined. Oxide-charge-induced high-low-junction emitter (OCI-HLE) test cells which exhibit considerably higher voltage over the open circuit than was previously seen in n-on-p solar cells are described.

Lindholm, F. A.; Neugroschel, A.

1977-01-01

427

Light trapping in ultrathin plasmonic solar cells.  

PubMed

We report on the design, fabrication, and measurement of ultrathin film a-Si:H solar cells with nanostructured plasmonic back contacts, which demonstrate enhanced short circuit current densities compared to cells having flat or randomly textured back contacts. The primary photocurrent enhancement occurs in the spectral range from 550 nm to 800 nm. We use angle-resolved photocurrent spectroscopy to confirm that the enhanced absorption is due to coupling to guided modes supported by the cell. Full-field electromagnetic simulation of the absorption in the active a-Si:H layer agrees well with the experimental results. Furthermore, the nanopatterns were fabricated via an inexpensive, scalable, and precise nanopatterning method. These results should guide design of optimized, non-random nanostructured back reflectors for thin film solar cells. PMID:20588593

Ferry, Vivian E; Verschuuren, Marc A; Li, Hongbo B T; Verhagen, Ewold; Walters, Robert J; Schropp, Ruud E I; Atwater, Harry A; Polman, Albert

2010-06-21

428

Passivated emitters in silicon solar cells  

NASA Astrophysics Data System (ADS)

In high-efficiency silicon solar cells with low metal contact coverage fractions and high bulk lifetimes, cell performance is often dominated by recombination in the oxide-passivated diffusions on the cell surface. Measurements of the emitter saturation current density, Jo, of oxide-passivated, boron and phosphorus diffusions are presented, and from these measurements, the dependence of surface recombination velocity on dopant concentration is extracted. The lowest observed values of Jo which are stable under UV light are given for both boron- and phosphorus-doped, oxide-passivated diffusions, for both textured and untextured surfaces. Contour plots which incorporate the above data were applied to two types of backside-contact solar cells with large area (37.5 sq cm) and one-sun efficiencies up to 22.7 percent.

King, Richard R.; Gruenbaum, Peter E.; Sinton, Ronald A.; Swanson, Richard M.

429

Direct-Write Contacts for Solar Cells  

SciTech Connect

We report on our project to develop inkjet printable contacts for solar cells. Ag, Cu, and Ni metallizations were inkjet printed with near vacuum deposition quality. Thick, highly conducting lines of Ag and Cu demonstrating good adhesion to glass, Si, and PCB have been printed at 100-200 C in air and N2, respectively. Ag grids were inkjet-printed on Si solar cells and fired through silicon nitride AR layer at 850 C resulting in 8% cells. Next-generation multicomponent inks (including etching agents) have also been developed with improved fire-through contacts leading to higher cell efficiencies. The approach developed can be easily extended to other conductors such as Pt, Pd, and Au, etc. In addition, PEDOT-PSS polymer-based conductors were inkjet-printed with the conductivity as good or better than those of polymer-based conductors.

Kaydanova, T.; van Hest, M.F.A.M.; Miedaner, A.; Curtis, C. J.; Alleman, J. L.; Dabney, M. S.; Garnett, E.; Shaheen, S.; Ginley, D. S.; Smith, L.; Collins, R.; Hanoka, J. I.; Gabor, A. M.

2005-01-01

430

Solar cell evaluation using electron beam induced current with the large chamber scanning electron microscope  

NASA Astrophysics Data System (ADS)

An initial study using electron beam induced current (EBIC) to evaluate solar cells has been carried out with the large chamber scanning electron microscope (LC-SEM) at the Western Kentucky University Nondestructive Analysis Center. EBIC is a scanning electron microscope technique used for the characterization of semiconductors. To facilitate our studies, we developed a Solar Amplification System (SASY) for analyzing current distribution and defects within a solar cell module. Preliminary qualitative results will be shown for a solar cell module that demonstrates the viability of the technique using the LC-SEM. Quantitative EBIC experiments will be carried out to analyze defects and minority carrier properties. Additionally, a well-focused spot of light from an LED mounted at the side of the SEM column will scan the same area of the solar cell using the LC-SEM positioning system. SASY will then output the solar efficiency to be compared with the minority carrier properties found using EBIC.

Wink, Tara; Kintzel, Edward; Marienhoff, Peter; Klein, Martin

2012-02-01

431

LARGE AREA METALLISATION WRAP THROUGH SOLAR CELLS WITH THICKFILM METALLISATION  

Microsoft Academic Search

Metallization Wrap Through (MWT) solar cells are back contact solar cells that can be processed with only a little extra effort compared to conventional cells. The cell concept is particularly suited for large area cells, which makes the concept attractive, since the size of the wafers processed by the industry is increasing. The MWT cells presented in this paper are

H. Knauss; P. Fath; W. Jooss; M. McCann; E. Rüland; S. Steckemetz

432

New Materials for Chalcogenide Based Solar Cells  

NASA Astrophysics Data System (ADS)

Thin film solar cells based on copper indium gallium diselenide (CIGS) have achieved efficiencies exceeding 20 %. The p-n junction in these solar cells is formed between a p-type CIGS absorber layer and a composite n-type film that consists of a 50-100 nm thin n-type CdS followed by a 50-200 nm thin n-type ZnO. This dissertation focuses on developing materials for replacing CdS and ZnO films to improve the damp-heat stability of the solar cells and for minimizing the use of Cd. Specifically, I demonstrate a new CIGS solar cell with better damp heat stability wherein the ZnO layer is replaced with SnO2. The efficiency of solar cells made with SnO2 decreased less than 5 % after 120 hours at 85 °C and 85 % relative humidity while the efficiency of solar cells made with ZnO declined by more than 70 %. Moreover, I showed that a SnO2 film deposited on top of completed CIGS solar cells significantly increased the device lifetime by forming a barrier against water diffusion. Semicrystalline SnO2 films deposited at room temperature had nanocrystals embedded in an amorphous matrix, which resulted in films without grain boundaries. These films exhibited better damp-heat stability than ZnO and crystalline SnO2 films deposited at higher temperature and this difference is attributed to the lack of grain boundary water diffusion. In addition, I studied CBD of Zn1-xCdxS from aqueous solutions of thiourea, ethylenediaminetetraacetic acid and zinc and cadmium sulfate. I demonstrated that films with varying composition (x) can be deposited through CBD and studied the structure and composition variation along the films' thickness. However, this traditional chemical bath deposition (CBD) approach heats the entire solution and wastes most of the chemicals by homogenous particle formation. To overcome this problem, I designed and developed a continuous-flow CBD approach to utilize the chemicals efficiently and to eliminate homogenous particle formation. Only the substrate is heated to the deposition temperature while the CBD solution is rapidly circulated between the bath and a chilled reservoir. We have demonstrated Zn1-x CdxS films for a variety of (x) values, with and without varying (x) across film thickness.

Tosun, Banu Selin

433

Lunar surface cosmic ray experiment. [including solar flare studies  

NASA Technical Reports Server (NTRS)

The galactic cosmic ray and solar flare experiment on Apollo 16 is reported. The published papers presented describe the experiment, equipment, data processing techniques, and operational history. The principle findings include: (1) The composition of heavy ions in interplanetary space at energies between approximately 30 and 130 MeV/nucleon is the same, within experimental errors. (2) The ability of a Lexan stack to determine simultaneously the energy spectra of major elements from He up to Fe in the energy interval 0.2 to 30 MeV/nucleon revealed systematic changes in the composition of solar flare particles as a function of energy. (3) Heavy ions emitted in a solar flare appear to be completely stripped of electrons, and are not in charge equilibrium at the time of acceleration and releases from the sun.

Price, P. B.

1974-01-01

434

The 1-kW solar Stirling experiment  

NASA Technical Reports Server (NTRS)

The objective of this experiment was to demonstrate electrical power generation using a small free-piston Stirling engine and linear alternator in conjunction with a parabolic solar collector. A test bed collector, formerly used at the JPL Table Mountain Observatory, was renovated and used to obtain practical experience and to determine test receiver performance. The collector was mounted on a two-axis tracker, with a cold water calorimeter mounted on the collector to measure its efficiency, while a separate, independently tracking radiometer was used to measure solar insolation. The solar receiver was designed to absorb energy from the collector, then transfer the resulting thermal energy to the Stirling engine. Successful testing of receiver/collector assembly yielded valuable inputs for design of the Stirling engine heater head.

Giandomenico, A.

1981-01-01

435

Laser scanning of experimental solar cells  

Microsoft Academic Search

A description is presented of a laser scanning instrument which makes it possible to display and measure the spatial response of a solar cell. Examples are presented to illustrate the use of generated micrographs in the isolation of flaws and features of the cell. The laser scanner system uses a 4 mW, CW helium-neon laser, operating a wavelength of 0.633

B. C. Plunkett; P. G. Lasswell

1980-01-01

436

Status of silicon solar cell technology  

NASA Technical Reports Server (NTRS)

Major progress in solar cell technology leading to increased efficiency has occurred since 1970. Technical approaches leading to this increased output include surface texturing, improved antireflection coatings, reduced grid pattern area coverage, shallow junctions and back surface fields. The status of these developments and their incorporation into cell production is discussed. Future research and technology trends leading to further efficiency increases and substantial cost reductions are described.

Brandhorst, H. W., Jr.

1976-01-01

437

High-efficiency silicon solar cells  

Microsoft Academic Search

Silicon solar cells are described which operate at energy conversion efficiencies independently measured at 18.7 percent under standard terrestrial test conditions (AM1.5, 100 mW\\/cm², 28°C). These are apparently the most efficient silicon cells fabricated to date. The high-efficiency results from a combination of high open-circuit voltage due to the careful attention paid to the passivation of the top surface of

M. A. Green; A. W. Blakers; Jiqun Shi; E. M. Keller; S. R. Wenham

1984-01-01

438

Copper metallization for crystalline Si solar cells  

Microsoft Academic Search

Cu metallization for crystalline Si solar cells was investigated using either Ti or Ti\\/TiN diffusion barriers. The resistivity and the specific contact resistance change were measured for both Ti(30nm)\\/Cu(100nm) and Ti(30nm)\\/TiN(30nm)\\/Cu(100nm) contact structures under various annealing conditions. As the annealing temperature increased, the efficiency of the cells increased mainly due to the increase in fill-factor and ISC, which was correlated

JaeSung You; Jinmo Kang; Donghwan Kim; James Jungho Pak; Choon Sik Kang

2003-01-01

439

Recent developments in thin film solar cells  

Microsoft Academic Search

The present status of the development of thin film solar cells is reviewed, with emphasis on important areas for further research. The following aperture-area efficiencies were measured for thin film modules: a-Si:H, 9.8 percent, 933 sq cm; CuIn(Ga)Se2, 11.1 percent, 938 sq cm; and CdTe, 7.3 percent, 838 sq cm. CuIn(Ga)Se2 cells and modules demonstrated excellent efficiencies and stability. The

Neelkanth G. Dhere

1990-01-01

440

Recent progress in aSi solar cells  

Microsoft Academic Search

As concern regarding global environmental problems such as the greenhouse effect and acid rain has increased, so too has the demand for commercially viable solar cells as a clean energy source. Interest in amorphous silicon (a-Si) solar cells has been particulary high, due to their low cost. Technological developments in the field of a-Si solar cells are discussed from the

Shinya Tsuda; Souichi Sakai; Shoichi Nakano

1997-01-01

441

Diagnostic structures for epitaxial thin silicon solar cells  

Microsoft Academic Search

The value of a high performance thin silicon solar cell is based on high open circuit voltage (Voc) which is highly dependent upon surface and interface recombination. A microelectronic approach with the series and parallel fabrication of different device structures is presented. This approach includes the fabrication of planar solar cells based on different solar cell designs that maximize Voc.

C. Paola Murcia; Ruiying Hao; Tim Creazzo; Kevin Shreve; Anthony Lochtefeld; Michael Curtin; Allen Barnett

2010-01-01

442

Solar cell panel crack detection using Particle Swarm Optimization algorithm  

Microsoft Academic Search

A solar cell panel as an efficient power source for the production of electrical energy has long been considered. Any defect on the solar cell panel's surface will be lead to reduced production of power and loss in the yield. In this case, inspection of the solar cell panel is essential to be performed to obtain a product of high

Amir Hossein Aghamohammadi; Anton Satria Prabuwono; Shahnorbanun Sahran; Marzieh Mogharrebi

2011-01-01

443

Business, market and intellectual property analysis of polymer solar cells  

Microsoft Academic Search

The business potential of polymer solar cells is reviewed and the market opportunities analyzed on the basis of the currently reported and projected performance and manufacturing cost of polymer solar cells. Possible new market areas are identified and described. An overview of the present patent and intellectual property situation is also given and a patent map of polymer solar cells

Torben D. Nielsen; Craig Cruickshank; Søren Foged; Jesper Thorsen; Frederik C. Krebs

2010-01-01

444

Silvaco ATLAS as a solar cell modeling tool  

Microsoft Academic Search

This paper presents research efforts conducted at the Naval Postgraduate School in the development of an accurate, physically-based solar cell model using the general-purpose ATLAS device simulator by Silvaco International. Unlike solar cell models based on a combination of discrete electrical components, this novel model extracts the electrical characteristics of a solar cell based on virtual fabrication of its physical

S. Michael; A. D. Bates; M. S. Green

2005-01-01

445

Space Radiation Effects in Advanced Solar Cell Materials and Devices  

Microsoft Academic Search

An investigation of the physical mechanisms governing the response of III-V based solar cells to particle irradiation is presented. The effect of particle irradiation on single and multijunction solar cells is studied through current vs. voltage, spectral response, and deep level transient spectroscopy measurements. The basic radiation response mechanisms are identified, and their effects on the solar cell electrical performance

R. J. Walters; G. P. Summers

446

Flexible thermal cycle test equipment for concentrator solar cells  

DOEpatents

A system and method for performing thermal stress testing of photovoltaic solar cells is presented. The system and method allows rapid testing of photovoltaic solar cells under controllable thermal conditions. The system and method presents a means of rapidly applying thermal stresses to one or more photovoltaic solar cells in a consistent and repeatable manner.

Hebert, Peter H. (Glendale, CA); Brandt, Randolph J. (Palmdale, CA)

2012-06-19

447

PN junction fabrication of solar cells and integration with metamaterials  

Microsoft Academic Search

Silicon is the primary material used for the fabrication of solar cells and it is responsible for about 40% of the cost. Metamaterials show promise in enhancing the performance of silicon solar cells thus, improving the efficiency. Here we report on the fabrication of a broadband, antireflective, conductive metamaterial capable of channeling light into a solar cell. As a precursor

Amarachukwu Enemuo; David T. Crouse; Michael Crouse

2011-01-01

448

Micro Solar Cells with Concentration and Light Trapping Optics  

NASA Astrophysics Data System (ADS)

Compared with conventional bulk plate semiconductor solar cells, micro solar cells provide opportunity for novel design geometry and provide test bed for light trapping at the device level as well as module level. Surface recombination, however, will have to be addressed properly as the much increased surface area due to the reduced dimension is more prominent in these devices than conventional solar cells. In this poster, we present experimental demonstration of silicon micro solar cells with concentration and light trapping optics. Silicon micro solar cell with optimized surface passivation and doping profile that exhibit high efficiency is demonstrated. Effective incorporation of high quantum yield fluorescent centers in the polymer matrix into which micro solar cell was encapsulated was investigated for luminescent solar concentration application. Micro-cell on a semi-transparent, nanopatterned reflector formed by soft-imprint lithography was investigated for near field effect related solar conversion performance enhancement.

Li, Lanfang; Breuckner, Eric; Corcoran, Christopher; Yao, Yuan; Xu, Lu; Nuzzo, Ralph

2013-03-01

449

Search for solar axions: the CAST experiment  

SciTech Connect

thetical axion-like particles with a two-photon interaction would be produced in the sun by the Primakoff process. In a laboratory magnetic field they would be transformed into X-rays with energies of a few keV. The CAST experiment at CERN is using a decommissioned LHC magnet as an axion helioscope in order to search for these axion-like particles. The analysis of the 2003 data showed no signal above the background, thus implying an upper limit to the axion-photon coupling of ga{gamma} < 1.16 x 10-10 GeV-1 at 95% CL for ma < or approx. 0.02 eV. The stable operation of the experiment during 2004 data taking allowed us to lower down this parameter to a preliminary value of ga{gamma} < 0.9 x 10-10 GeV-1.

Andriamonje, S.; Aune, S.; Ferrer-Ribas, E.; Giomataris, I. [DAPNIA, Centre d'Etudes Nucleaires de Saclay (CEA-Saclay), Gif-sur-Yvette (France); Barth, K.; Davenport, M.; Lasseur, C.; Papaevangelou, T.; Placci, A.; Stewart, L.; Walckiers, L. [European Organization for Nuclear Research (CERN), Geneve (Switzerland); Belov, A.; Gninenko, S. [Institute for Nuclear Research (INR), Russian Academy of Sciences, Moscow (Russian Federation); Beltran, B. [Instituto de Fisica Nuclear y Altas Energias, Universidad de Zaragoza, Zaragoza (Spain); DAPNIA, Centre d'Etudes Nucleaires de Saclay (CEA-Saclay), Gif-sur-Yvette (France); Braeuninger, H.; Englhauser, J.; Friedrich, P. [Max-Planck-Institut fuer extraterrestrische Physik, Garching (Germany); Carmona, J. M.; Cebrian, S.; Luzon, G. [Instituto de Fisica Nuclear y Altas Energias, Universidad de Zaragoza, Zaragoza (Spain)] (and others)

2006-11-28

450

High efficiency crystalline silicon solar cells  

NASA Technical Reports Server (NTRS)

A review of the entire research program since its inception ten years ago is given. The initial effort focused on the effects of impurities on the efficiency of silicon solar cells to provide figures of maximum allowable impurity density for efficiencies up to about 16 to 17%. Highly accurate experimental techniques were extended to characterize the recombination properties of the residual imputities in the silicon solar cell. A numerical simulator of the solar cell was also developed, using the Circuit Technique for Semiconductor Analysis. Recent effort focused on the delineation of the material and device parameters which limited the silicon efficiency to below 20% and on an investigation of cell designs to break the 20% barrier. Designs of the cell device structure and geometry can further reduce recombination losses as well as the sensitivity and criticalness of the fabrication technology required to exceed 20%. Further research is needed on the fundamental characterization of the carrier recombination properties at the chemical impurity and physical defect centers. It is shown that only single crystalline silicon cell technology can be successful in attaining efficiencies greater than 20%.

Sah, C. Tang

1986-01-01

451

Nanocluster production for solar cell applications  

SciTech Connect

This research focuses on the fabrication and characterization of silver (Ag) and silicon (Si) nanoclusters that might be used for solar cell applications. Silver and silicon nanoclusters have been synthesized by means of dc magnetron sputtering and inert gas condensation inside an ultra-high vacuum compatible system. We have found that nanocluster size distributions can be tuned by various source parameters, such as the sputtering discharge power, flow rate of argon inert gas, and aggregation length. Quadrupole mass filter and transmission electron microscopy were used to evaluate the size distribution of Ag and Si nanoclusters. Ag nanoclusters with average size in the range of 3.6–8.3 nm were synthesized (herein size refers to the nanocluster diameter), whereas Si nanoclusters' average size was controlled to range between 2.9 and 7.4 nm by controlling the source parameters. This work illustrates the ability of controlling the Si and Ag nanoclusters' sizes by proper optimization of the operation conditions. By controlling nanoclusters' sizes, one can alter their surface properties to suit the need to enhance solar cell efficiency. Herein, Ag nanoclusters were deposited on commercial polycrystalline solar cells. Short circuit current (I{sub SC}), open circuit voltage (V{sub OC}), fill factor, and efficiency (?) were obtained under light source with an intensity of 30 mW/cm{sup 2}. A 22.7% enhancement in solar cell efficiency could be measured after deposition of Ag nanoclusters, which demonstrates that Ag nanoclusters generated in this work are useful to enhance solar cell efficiency.

Al Dosari, Haila M.; Ayesh, Ahmad I. [Department of Physics, United Arab Emirates University, P. O. Box 15551, Al Ain (United Arab Emirates)] [Department of Physics, United Arab Emirates University, P. O. Box 15551, Al Ain (United Arab Emirates)

2013-08-07

452

Experiments on solar photovoltaic power generation using concentrator and liquid cooling  

Microsoft Academic Search

Calculations and experimental data are presented leading to the development of a practical, economical solar photovoltaic power supply. The concept involves concentration of sunlight up to about 100 times normal solar intensity in a solar tracking collector and directing this to an array of solar cells. The cells are immersed in water circulated from a thermal reservoir which limits cell

B. H. Beam; C. F. Hansen

1975-01-01

453

Digital solar edge tracker for the Halogen Occultation Experiment  

Microsoft Academic Search

The optical and electronic design of the Halogen Occultation Experiment (Haloe) elevation sun sensor is described. The Haloe instrument is a gas-correlation radiometer now being developed at NASA Langley for the Upper Atmosphere Research Satellite. The system uses a Galilean telescope to form a solar image on a linear silicon photodiode array. The array is a self-scanned monolithic CCD. The

L. E. Mauldin III; A. S. Moore; C. W. Stump; L. S. Mayo

1987-01-01

454

Solar Dynamic Power System Concept: Terrestrial Experiences and Their Extension to Space Applications.  

National Technical Information Service (NTIS)

The characteristics of solar thermal concentration power systems for terrestrial applications are described. Designs and experiences on steam and gas solar plants and components are reported. Comparison of alternatives for use in solar dynamic power syste...

A. Lucifredi E. Ravina F. Repetto

1986-01-01

455

Plastic Schottky barrier solar cells  

DOEpatents

A photovoltaic cell structure is fabricated from an active medium including an undoped, intrinsically p-type organic semiconductor comprising polyacetylene. When a film of such material is in rectifying contact with a magnesium electrode, a Schottky-barrier junction is obtained within the body of the cell structure. Also, a gold overlayer passivates the magnesium layer on the undoped polyacetylene film.

Waldrop, James R. (Thousand Oaks, CA); Cohen, Marshall J. (Thousand Oaks, CA)

1984-01-24

456

Experimental and simulation analysis of the dye sensitized solar cell\\/Cu(In,Ga)Se 2 solar cell tandem structure  

Microsoft Academic Search

A novel tandem structure composed of dye sensitized solar cell (DSC) and CuInGaSe2 (CIGS) solar cell shows the potential to increase conversion efficiency by fully utilizing the sunlight. In our research, a tandem solar cell with a high open-circuit voltage of 1.15V and a conversion efficiency of 10.46%, which is both larger than that of DSC and CIGS solar cell

W. L. Wang; H. Lin; J. Zhang; X. Li; A. Yamada; M. Konagai; J. B. Li

2010-01-01

457

Enhancing Solar Cell Efficiencies through 1-D Nanostructures  

PubMed Central

The current global energy problem can be attributed to insufficient fossil fuel supplies and excessive greenhouse gas emissions resulting from increasing fossil fuel consumption. The huge demand for clean energy potentially can be met by solar-to-electricity conversions. The large-scale use of solar energy is not occurring due to the high cost and inadequate efficiencies of existing solar cells. Nanostructured materials have offered new opportunities to design more efficient solar cells, particularly one-dimensional (1-D) nanomaterials for enhancing solar cell efficiencies. These 1-D nanostructures, including nanotubes, nanowires, and nanorods, offer significant opportunities to improve efficiencies of solar cells by facilitating photon absorption, electron transport, and electron collection; however, tremendous challenges must be conquered before the large-scale commercialization of such cells. This review specifically focuses on the use of 1-D nanostructures for enhancing solar cell efficiencies. Other nanostructured solar cells or solar cells based on bulk materials are not covered in this review. Major topics addressed include dye-sensitized solar cells, quantum-dot-sensitized solar cells, and p-n junction solar cells.

2009-01-01

458

Hypervelocity Impact Studies on Solar Cell Modules  

NASA Technical Reports Server (NTRS)

Space environmental effects have caused severe problems as satellites move toward increased power and operating voltage levels. The greatest unknown, however, is the effect of high velocity micrometeoroid impacts on high voltage arrays (>200V). Understanding such impact phenomena is necessary for the design of future reliable, high voltage solar arrays, especially for Space Solar Power applications. Therefore, the objective of this work was to study the effect of hypervelocity impacts on high voltage solar arrays. Initially, state of the art, 18% efficient GaAs solar cell strings were targeted. The maximum bias voltage on a two-cell string was -200 V while the adjacent string was held at -140 V relative to the plasma potential. A hollow cathode device provided the plasma. Soda lime glass particles 40-120 micrometers in diameter were accelerated in the Hypervelocity Impact Facility to velocities as high as 11.6 km/sec. Coordinates and velocity were obtained for each of the approximately 40 particle impact sites on each shot. Arcing did occur, and both discharging and recharging of arcs between the two strings was observed. The recharging phenomena appeared to stop at approximately 66V string differential. No arcing was observed at 400 V on concentrator cell modules for the Stretched Lens Array.

Brandhorst, Henry W., Jr.; Best, Stevie R.

2001-01-01

459

Space solar cell technology development - A perspective  

NASA Technical Reports Server (NTRS)

The developmental history of photovoltaics is examined as a basis for predicting further advances to the year 2000. Transistor technology was the precursor of solar cell development. Terrestrial cells were modified for space through changes in geometry and size, as well as the use of Ag-Ti contacts and manufacture of a p-type base. The violet cell was produced for Comsat, and involved shallow junctions, new contacts, and an enhanced antireflection coating for better radiation tolerance. The driving force was the desire by private companies to reduce cost and weight for commercial satellite power supplies. Liquid phase epitaxial (LPE) GaAs cells are the latest advancement, having a 4 sq cm area and increased efficiency. GaAs cells are expected to be flight ready in the 1980s. Testing is still necessary to verify production techniques and the resistance to electron and photon damage. Research will continue in CVD cell technology, new panel technology, and ultrathin Si cells.

Scott-Monck, J.

1982-01-01

460

Solar Airplanes and Regenerative Fuel Cells  

NASA Technical Reports Server (NTRS)

A solar electric aircraft with the potential to "fly forever" has captured NASA's interest, and the concept for such an aircraft was pursued under Aeronautics Environmental Research Aircraft and Sensor Technology (ERAST) project. Feasibility of this aircraft happens to depend on the successful development of solar power technologies critical to NASA's Exploration Initiatives; hence, there was widespread interest throughout NASA to bring these technologies to a flight demonstration. The most critical is an energy storage system to sustain mission power during night periods. For the solar airplane, whose flight capability is already limited by the diffuse nature of solar flux and subject to latitude and time of year constraints, the feasibility of long endurance flight depends on a storage density figure of merit better than 400-600 watt-hr per kilogram. This figure of merit is beyond the capability of present day storage technologies (other than nuclear) but may be achievable in the hydrogen-oxygen regenerative fuel cell (RFC). This potential has led NASA to undertake the practical development of a hydrogen-oxygen regenerative fuel cell, initially as solar energy storage for a high altitude UAV science platform but eventually to serve as the primary power source for NASAs lunar base and other planet surface installations. Potentially the highest storage capacity and lowest weight of any non-nuclear device, a flight-weight RFC aboard a solar-electric aircraft that is flown continuously through several successive day-night cycles will provide the most convincing demonstration that this technology's widespread potential has been realized. In 1998 NASA began development of a closed cycle hydrogen oxygen PEM RFC under the Aeronautics Environmental Research Aircraft and Sensor Technology (ERAST) project and continued its development, originally for a solar electric airplane flight, through FY2005 under the Low Emissions Alternative Power (LEAP) project. Construction of the closed loop system began in 2002 at the NASA Glenn Research Center in Cleveland, Ohio. System checkout was completed, and testing began, in July of 2003. The initial test sequences were done with only a fuel cell or electrolyzer in the test rig. Those tests were used to verify the test apparatus, procedures, and software. The first complete cycles of the fully closed loop, regenerative fuel cell system were successfully completed in the following September. Following some hardware upgrades to increase reactant recirculation flow, the test rig was operated at full power in December 2003 and again in January 2004. In March 2004 a newer generation of fuel cell and electrolyzer stacks was substituted for the original hardware and these stacks were successfully tested at full power under cyclic operation in June of 2004.

Bents, David J.

2007-01-01

461

Labeling Solar-Cell Modules  

NASA Technical Reports Server (NTRS)

Photocopying machine produces durable identification label. Process used for double glass photovoltaic-cell modules. Matrix of cells sandwiched between thin, flexible glass mats and covered above and below by protective sheets of glass. Label contains such information as manufacturer, model number, voltage and power ratings, and serial number. May also contain electrical-shock hazard warning and identification of positive and negative terminals. Method saves expense of procuring and applying conventional labels.

Watson, E. G.; Coyle, P. J.

1984-01-01

462

High Concentrating GaAs Cell Operation Using Optical Waveguide Solar Energy System  

NASA Technical Reports Server (NTRS)

This paper discusses the result of the concentrating photovoltaic (CPV) cell experiments conducted with the Optical Waveguide (OW) Solar Energy System. The high concentration GaAs cells developed by Research Triangle Institute (RTI) were combined with the OW system in a "fiber-on-cell" configuration. The sell performance was tested up to the solar concentration of 327. Detailed V-I characteristics, power density and efficiency data were collected. It was shown that the CPV cells combined with the OW solar energy system will be an effective electric power generation device.

Nakamura, T.; Case, J. A.; Timmons, M. L.

2004-01-01

463

The solar dynamic power system concept: Terrestrial experiences and their extension to space applications  

Microsoft Academic Search

The characteristics of solar thermal concentration power systems for terrestrial applications are described. Designs and experiences on steam and gas solar plants and components are reported. Comparison of alternatives for use in solar dynamic power systems (photovoltaic, solar dynamic, nuclear) shows an intermediate range of power where a potential exists for the use of solar dynamic systems adopting parabolic dish

A. Lucifredi; E. Ravina; F. Repetto

1986-01-01

464

Production technology for high efficiency ion implanted solar cells  

NASA Technical Reports Server (NTRS)

Ion implantation is being developed for high volume automated production of silicon solar cells. An implanter designed for solar cell processing and able to properly implant up to 300 4-inch wafers per hour is now operational. A machine to implant 180 sq m/hr of solar cell material has been designed. Implanted silicon solar cells with efficiencies exceeding 16% AM1 are now being produced and higher efficiencies are expected. Ion implantation and transient processing by pulsed electron beams are being integrated with electrostatic bonding to accomplish a simple method for large scale, low cost production of high efficiency solar cell arrays.

Kirkpatrick, A. R.; Minnucci, J. A.; Greenwald, A. C.; Josephs, R. H.

1978-01-01

465

A dye-sensitized solar cell driven electrochromic device  

Microsoft Academic Search

A new dye-sensitized solar cell driven electrochromic device has been fabricated. The device consists of an electrochromic display and a solar cell in a single nanocrystalline film. The optimization of the electrochromic and the solar cell functions was carried out. An applied potential of 1.0 V was required for coloring and the best solar energy conversion efficiency 1.1% was achieved.

Henriette Santa-Nokki; Jani Kallioinen; Jouko Korppi-Tommola

2007-01-01

466

Thin foil silicon solar cells with coplanar back contacts  

NASA Technical Reports Server (NTRS)

To fabricate 50 microns thick, coplanar back contact (CBC) silicon solar cells, wraparound junction design was selected and proved to be effective. The process sequence used, the cell design, and the cell performance are described. CBC cells with low solar absorptance have shown AMO efficiencies to 13%, high cells up to 14%; further improvements are projected with predictable optimization.

Ho, F.; Iles, P. A.; Baraona, C. R.

1981-01-01

467

Reanalysis of the GALLEX solar neutrino flux and source experiments  

NASA Astrophysics Data System (ADS)

After the completion of the gallium solar neutrino experiments at the Laboratori Nazionali del Gran Sasso ( GALLEX: 1991-1997; GNO: 1998-2003) we have retrospectively updated the GALLEX results with the help of new technical data that were impossible to acquire for principle reasons before the completion of the low rate measurement phase (that is, before the end of the GNO solar runs). Subsequent high rate experiments have allowed the calibration of absolute internal counter efficiencies and of an advanced pulse shape analysis for counter background discrimination. The updated overall result for GALLEX (only) is 73.4-7.3+7.1 SNU. This is 5.3% below the old value of 77.5-7.8+7.5 SNU ( GALLEX Collaboration, W. Hampel et al., 1999 [1]), with a substantially reduced error. A similar reduction is obtained from the reanalysis of the 51Cr neutrino source experiments of 1994/1995.

Kaether, F.; Hampel, W.; Heusser, G.; Kiko, J.; Kirsten, T.

2010-02-01

468

Development of integral covers on solar cells  

NASA Technical Reports Server (NTRS)

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

Stella, P.; Somberg, H.

1971-01-01

469

Thermal runaway in multijunction solar cells  

NASA Astrophysics Data System (ADS)

A small fraction of GaInP2/GaAs/Ge triple junction solar cells exposed to the 6× concentrated air mass zero spectrum at 523 K for 5 min was found to be severely shunted afterwards. A combination of electroluminescence imaging and focused ion beam cross sectioning revealed that pre-existing top-middle cell shunts were responsible for the observed degradation. Joule heating in the shunt resistance limiting Ge substrate is modeled and exhibits a thermal runaway effect above a critical voltage, in agreement with the experimental observation. The implications for current and future multijunction cells are discussed.

Zimmermann, Claus G.

2013-06-01

470

Advanced high efficiency wraparound contact solar cell  

NASA Technical Reports Server (NTRS)

A significant advancement in the development of thin high efficiency wraparound contact silicon solar cells has been made by coupling space and terrestrial processing procedures. Although this new method for fabricating cells has not been completely reduced to practice, some of the initial cells have delivered over 20 mW/sq cm when tested at 25 C under AMO intensity. This approach not only yields high efficiency devices, but shows promise of allowing complete freedom of choice in both the location and size of the wraparound contact pad area.

Scott-Monck, J. A.; Uno, F. M.; Thornhill, J. W.

1977-01-01

471

Advanced high efficiency wraparound contact solar cell  

NASA Technical Reports Server (NTRS)

A significant advancement in the development of thin high efficiency wraparound contact silicon solar cells has been made by coupling space and terrestrial processing procedures. Although this new method for fabricating cells has not been completely reduced to practice, some of the initial cells have delivered over 20 mW/sq cm when tested at 25 C under AMO intensity. This approach not only yields high efficiency devices, but shows promise of allowing complete freedom of choice in both the location and size of the wraparound contact pad area

Scott-Monck, J. A.; Uno, F. M.; Thornhill, J. W.

1977-01-01

472

Multijunction high voltage concentrator solar cells  

NASA Technical Reports Server (NTRS)

The standard integrated circuit technology has been developed to design and fabricate new innovative planar multi-junction solar cell chips for concentrated sunlight applications. This 1 cm x 1 cm cell consisted of several voltage generating regions called unit cells which were internally connected in series within a single chip resulting in high open circuit voltages. Typical open-circuit voltages of 3.6 V and short-circuit currents of 90 ma were obtained at 80 AM1 suns. A dramatic increase in both short circuit current and open circuit voltage with increased light levels was observed.

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

1981-01-01

473

Oxide nanowires for solar cell applications  

NASA Astrophysics Data System (ADS)

Oxide nanowire arrays were studied for their applications to solar cells. It was demonstrated that the nanowires could provide direct pathways for electron transport in dye-sensitized solar cells and therefore, while forming photoelectrode films, they offered better suppression of charge recombination than nanoparticles. However, the photoelectron films consisting of nanowires suffered a disadvantage in giving large surface area for dye adsorption. Such a shortcoming of nanowires had been exemplified in this paper illustrating that it could be well compensated by incorporating with nanoparticles to form a nanoparticle-nanowire array hybrid photoelectrode film. The oxide nanowires were also demonstrated to be able to enhance the performance of inverted structure polymer solar cells as a cathode buffer layer by establishing a large interface with the polymers so as to facilitate the transport of photogenerated electrons from the polymer to the electron collecting electrode. Such an enhancement effect could be further boosted while the nanowires were replaced with nanotubes; the latter may build up larger interface with the polymers than the former and therefore facilitates the electron transport more efficiently.Oxide nanowire arrays were studied for their applications to solar cells. It was demonstrated that the nanowires could provide direct pathways for electron transport in dye-sensitized solar cells and therefore, while forming photoelectrode films, they offered better suppression of charge recombination than nanoparticles. However, the photoelectron films consisting of nanowires suffered a disadvantage in giving large surface area for dye adsorption. Such a shortcoming of nanowires had been exemplified in this paper illustrating that it could be well compensated by incorporating with nanoparticles to form a nanoparticle-nanowire array hybrid photoelectrode film. The oxide nanowires were also demonstrated to be able to enhance the performance of inverted structure polymer solar cells as a cathode buffer layer by establishing a large interface with the polymers so as to facilitate the transport of photogenerated electrons from the polymer to the electron collecting electrode. Such an enhancement effect could be further boosted while the nanowires were replaced with nanotubes; the latter may build up larger interface with the polymers than the former and therefore facilitates the electron transport more efficiently. This article was submitted as part of a collection highlighting papers on the `Recent Advances in Semiconductor Nanowires Research' from ICMAT 2011.

Zhang, Qifeng; Yodyingyong, Supan; Xi, Junting; Myers, Daniel; Cao, Guozhong

2012-02-01

474

Variation of solar cell sensitivity and solar radiation on tilted surfaces  

NASA Technical Reports Server (NTRS)

The validity is studied that one of various insolation models used to compute solar radiation incident on tilted surfaces from global data measured on horizontal surfaces. The variation of solar cell sensitivity to solar radiation is determined over a wide range of atmospheric condition. A new model was formulated that reduced the deviations between measured and predicted insolation to less than 3 percent. Evaluation of solar cell sensitivity data indicates small change (2-3 percent) in sensitivity from winter to summer for tilted