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1

Solar Cell Calibration Experiments on Les-6.  

National Technical Information Service (NTIS)

The sixth Lincoln Laboratory Experimental Satellite (LES-6) was placed in a synchronous orbit on 26 September 1968. Among instrumentation on board is a solar cell calibration experiment to measure the V-I characteristics at various angles of solar inciden...

F. W. Sarles A. G. Stanley C. Burrowes

1968-01-01

2

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

3

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

4

Results from the IMP-J violet solar cell experiment and violet cell balloon flights  

Microsoft Academic Search

The Interplanetary Monitoring Platform-J violet solar cell experiment was flown in an orbit with mild thermal cycling and low hard-particle radiation. The results of the experiment show that violet cells degrade at about the same rate as conventional cells in such an orbit. Balloon flight measurements show that violet solar cells produce approximately 20% more power than conventional cells.

E. M. Gaddy

1976-01-01

5

Solar cells  

Microsoft Academic Search

Solar cells are based on the photovoltaic effect of converting solar energy into electric energy. The mechanism for solar cells is divided into steps, that is, electron-hole pair generation by absorption of light in semiconductors, separation of electron-hole pairs by built-in potential, electron-hole recombination, collection of charge carriers by metal electrodes, etc. In this article, the principle and the theories

Hiroshi Tsubomura; Hikaru Kobayashi

1993-01-01

6

Solar-cell power system for the BESS Polar Experiment  

Microsoft Academic Search

The Balloon-born Experiment with a Superconducting Spectrometer (BESS), aiming to search for antiparticle\\/antimatter in the cosmic radiation, successfully carried out two long-duration flights over Antarctica in 2004 (BESS Polar-I, 8.5days) and 2007\\/2008 (BESS Polar-II, 24.5days science, 29.5 days total). To achieve the long duration flights, establishment of a reliable power supply system was one of our new challenges. The requirements

Masaya Hasegawa

2008-01-01

7

Experiences with solar power  

NASA Astrophysics Data System (ADS)

Experience with solar thermal plants is reviewed. The component and subsystems development of the last decade and particularly the receiver, collector and heliostat field development is a technical success. Solar specific problems on the system and component level arose, when off the shelf solutions of fossile fired plants were transferred uncritically. It is shown that concentrated solar radiation is a relatively cheap high quality fuel. Other uses than electricity generation are high temperature processes and the production of solar fuels and chemicals. A technical and economic comparison of solar thermal and photovoltaic electricity generation is made.

Kesselring, P.

1985-11-01

8

TIMED Solar EUV experiment  

Microsoft Academic Search

The Solar EUV Experiment (SEE) selected for the NASA Thermosphere, Ionosphere, and Mesosphere Energetics and Dynamics (TIMED) mission will measure the solar vacuum ultraviolet (VUV) spectral irradiance from 0.1 to 200 nm. To cover this wide spectral range two different types of instruments are used: a grating spectrograph for spectra above 25 nm and a set of silicon soft x-ray

Thomas N. Woods; Scott Bailey; Frank Eparvier; George Lawrence; Judith Lean; Bill McClintock; Raymond Roble; Gary J. Rottman; Stanley C. Solomon; W. Kent Tobiska

2000-01-01

9

Silicon solar cells with nano-crystalline silicon down shifter: experiment and modeling  

Microsoft Academic Search

Materials used as luminescent down shifters (LDS) have to absorb light effectively in the spectral area where solar cells have poor internal quantum efficiency. At the same time these materials have to emit most of the absorbed spectral powers at lower energies where the internal quantum efficiency of the solar cell is close to the maximum. The effects of silicon

Yoann Jestin; Georg Pucker; Mher Ghulinyan; Lorenza Ferrario; Pierluigi Bellutti; Antonio Picciotto; Amos Collini; Alessandro Marconi; Aleksei Anopchenko; Zhizhong Yuan; Lorenzo Pavesi

2010-01-01

10

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

11

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

12

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

13

Solar Cells and Solar Panels.  

National Technical Information Service (NTIS)

The bibliography is a selection of unclassified and unlimited distribution references on Solar Cells and Solar Panels. These citations of reports present information on performance characteristics, fabrication, development of power levels, degradation stu...

1973-01-01

14

Chlorine solar neutrino experiment  

SciTech Connect

The chlorine solar neutrino experiment in the Homestake Gold Mine is described and the results obtained with the chlorine detector over the last fourteen years are summarized and discussed. Background processes producing /sup 37/Ar and the question of the constancy of the production rate of /sup 37/Ar are given special emphasis.

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

1984-01-01

15

Analysis of Space Environment Damage to Solar Cell Assemblies from LDEF Experiment A0171-GSFC Test Plate.  

National Technical Information Service (NTIS)

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) sola...

D. C. Hill M. F. Rose

1994-01-01

16

Silicon solar cells with nano-crystalline silicon down shifter: experiment and modeling  

NASA Astrophysics Data System (ADS)

Materials used as luminescent down shifters (LDS) have to absorb light effectively in the spectral area where solar cells have poor internal quantum efficiency. At the same time these materials have to emit most of the absorbed spectral powers at lower energies where the internal quantum efficiency of the solar cell is close to the maximum. The effects of silicon nanocrystals prepared by thermal treatment of a silicon-rich-oxide (SRO) layer on the efficiency of c-Si cells are investigated in this paper. The SRO layer is characterized by a high photoluminescence peak at around 800 nm. Influence of the active layer on light transmission and on the modification of the optical spectra due to photoluminescence generation has been determined with the help of optical measurements and transfer matrix simulations. The solar cell efficiency for cells with and without down-shifting layer were measured under illumination with AM1.5G solar spectrum and compared with the simulations. Finally, we model the behavior of cells with and without LDS layer showing that a cell with LDS suffers less from bad surface passivation.

Jestin, Yoann; Pucker, Georg; Ghulinyan, Mher; Ferrario, Lorenza; Bellutti, Pierluigi; Picciotto, Antonio; Collini, Amos; Marconi, Alessandro; Anopchenko, Aleksei; Yuan, Zhizhong; Pavesi, Lorenzo

2010-08-01

17

Solar Cell Radiation Handbook.  

National Technical Information Service (NTIS)

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 c...

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

1982-01-01

18

Solar Cell Radiation Handbook.  

National Technical Information Service (NTIS)

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...

J. R. Carter H. Y. Tada

1973-01-01

19

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

20

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

21

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…

Roman, Harry T.

2004-01-01

22

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

23

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

24

Solar molten salt electric experiment  

Microsoft Academic Search

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 Albuquerque, New Mexico. The Molten Salt Electric Experiment (MSEE) is a joint government, electric utility, and industry funded program that

1983-01-01

25

The chlorine solar neutrino experiment  

NASA Astrophysics Data System (ADS)

The present consideration of the fourteen years' (1970-1984) results from the Homestake Gold Mine chlorine solar neutrino experiment gives attention to background processes generating Ar-37, as well as the constancy of the Ar-37 production rate. The counter background rates derived from a maximum likelihood treatment are noted to have been variable. The results of the chlorine experiment are clearly different from those of Monte Carlo simulations, with a production rate 3-4 times higher. Solar cycle variations and solar flare effects are also discussed.

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

1985-01-01

26

Solar cell encapsulation  

SciTech Connect

A polymer syrup for encapsulating solar cell assemblies. The syrup includes uncrosslinked poly(n-butyl)acrylate dissolved in n-butyl acrylate monomer. Preparation of the poly(n-butyl)acrylate and preparation of the polymer syrup is disclosed. Methods for applying the polymer syrup to solar cell assemblies as an encapsulating pottant are described. Also included is a method for solar cell construction utilizing the polymer syrup as a dual purpose adhesive and encapsulating material.

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

1983-05-10

27

Nanocrystal solar cells  

Microsoft Academic Search

This dissertation presents the results of a research agenda aimed at improving integration and stability in nanocrystal-based solar cells through advances in active materials and device architectures. The introduction of 3-dimensional nanocrystals illustrates the potential for improving transport and percolation in hybrid solar cells and enables novel fabrication methods for optimizing integration in these systems. Fabricating cells by sequential deposition

Ilan Gur; Ilan

2006-01-01

28

Solar Cells and Solar Panels. Volume I.  

National Technical Information Service (NTIS)

An annotated bibliography is provided of documents in which performance characteristics of various solar cells, particularly types containing gallium arsenides, silicon, or cadmium sulfides, are evaluated. Other reports include solar-cell fabrication, dev...

1970-01-01

29

Colloidal nanocrystal solar cells  

Microsoft Academic Search

.  Colloidal nanocrystal based organic solar cells are envisaged to be a cost effective alternative to conventional inorganic\\u000a cells. A variety of studies have been reported recently with the goal to increases energy conversion efficiencies, which must\\u000a be pushed towards 10% for devices to be practical. We review the status of this work, critically examining the factors affecting\\u000a hybrid solar cell

Sandeep Kumar; Gregory D. Scholes

2008-01-01

30

Solar Energy Experiment  

NSDL National Science Digital Library

This experiment demonstrates that energy from the Sun can be collected and stored in a variety of ways. Using plastic bottles painted black and white and capped with balloons, students will see that the black bottle becomes warmer, heating the air inside it and blowing up the balloon.

31

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

32

Advanced Solar Panel Concentrator Experiment (ASPaCE)  

Microsoft Academic Search

The US Naval Research Laboratory (NRL) is beginning Phase II development for the Advanced Solar Panel Concentrator Experiment (ASPaCE). Phase I showed that flexible thin film reflectors can work successfully in a deployable trough concentrator. Thin film reflectors add several advantages to this concentrator including compact stowage, increased power from conventional fold-out solar panels, and solar cell exposure during orbit

B. P. Whalen

1997-01-01

33

Solar cell power supply circuit  

SciTech Connect

A solar cell power supply circuit for use in a calculator or equipment is disclosed. It includes a solar cell or cells, a back-up capacitor connected to the solar cells, and a circuit element connected to be responsive whether the electromotive force from the solar cells lies within a range of operation for a load element of the solar cells, typically an LSI semiconductor device. The back-up capacitor starts charging when the electromotive force of the solar cells falls out of the range of operation for the load element. Preferably, an alarm sound is delivered when the electromotive force of the solar cells is poor.

Higuchi, M.

1984-02-28

34

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

35

Vertical Multijunction Solar Cells.  

National Technical Information Service (NTIS)

A theoretical analysis of the vertical multijunction (VMJ) solar cell was performed which indicated that using silicon certain configurations could be fabricated to satisfy the program objectives. Results indicate that initial AMO efficiencies of 15% can ...

P. M. Stella

1973-01-01

36

Solar cell array interconnects  

DOEpatents

Electrical interconnects are disclosed for solar cells or other electronic components using a silver-silicone paste or a lead-tin (Pb-Sn) no-clean fluxless solder cream, whereby the high breakage of thin (<6 mil thick) solar cells using conventional solder interconnect is eliminated. The interconnects of this invention employs copper strips which are secured to the solar cells by a silver-silicone conductive paste which can be used at room temperature, or by a Pb-Sn solder cream which eliminates undesired residue on the active surfaces of the solar cells. Electrical testing using the interconnects of this invention has shown that no degradation of the interconnects developed under high current testing, while providing a very low contact resistance value. 4 figs.

Carey, P.G.; Thompson, J.B.; Colella, N.J.; Williams, K.A.

1995-11-14

37

Silicon for Solar Cells.  

National Technical Information Service (NTIS)

This report is an introduction to silicon solar cell technology and photovoltaic device operation. The conventional semiconductor industry techniques for extraction of Si from quartz, purification of silanes, chemical vapor deposition of polycrystalline s...

T. F. Ciszek

1984-01-01

38

Thin silicon solar cells  

SciTech Connect

The silicon-film design achieves high performance by using a dun silicon layer and incorporating light trapping. Optimally designed thin crystalline solar cells (<50 microns thick) have performance advantages over conventional thick devices. The high-performance silicon-film design employs a metallurgical barrier between the low-cost substrate and the thin silicon layer. Light trapping properties of silicon-film on ceramic solar cells are presented and analyzed. Recent advances in process development are described here.

Hall, R.B.; Bacon, C.; DiReda, V.; Ford, D.H.; Ingram, A.E.; Cotter, J.; Hughes-Lampros, T.; Rand, J.A.; Ruffins, T.R.; Barnett, A.M. [Astro Power Inc., Solar Park, Newark, DE (United States)

1992-12-01

39

Characterizing Variability in Smestad and Gratzel's Nanocrystalline Solar Cells: A Collaborative Learning Experience in Experimental Design  

ERIC Educational Resources Information Center

|This article describes a collaborative learning experience in experimental design that closely approximates what practicing statisticians and researchers in applied science experience during consulting. Statistics majors worked with a teaching assistant from the chemistry department to conduct a series of experiments characterizing the variation…

Lawson, John; Aggarwal, Pankaj; Leininger, Thomas; Fairchild, Kenneth

2011-01-01

40

Nanocrystal Solar Cells  

SciTech Connect

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

Gur, Ilan

2006-12-15

41

Parameterization of Solar Cells.  

National Technical Information Service (NTIS)

The aggregation (sorting) of the individual solar cells into an array is commonly based on a single operating point on the current-voltage (I-V) characteristic curve. An alternative approach for cell performance prediction and cell screening is provided b...

J. Appelbaum A. Chait D. Thompson

1992-01-01

42

Integrated solar cell array  

Microsoft Academic Search

An integrated array of solar cells, each cell having a positive and a negative electrode, is disclosed. A first grid comprising a plurality of non-intersecting electrically conductive members is affixed to an insulating substrate. Each single individual member of this grid forms the negative electrode of an individual cell of the array. Overlying and affixed to the negative electrodes and

W. J. Biter; F. A. Shirland

1980-01-01

43

Sliver solar cells  

NASA Astrophysics Data System (ADS)

Sliver solar cells are thin, mono-crystalline silicon solar cells, fabricated using micro-machining techniques combined with standard solar cell fabrication technology. Sliver solar modules can be efficient, low cost, bifacial, transparent, flexible, shadow-tolerant, and lightweight. Sliver modules require only 5 to 10% of the pure silicon and less than 5% of the wafer starts per MWp of factory output when compared with conventional photovoltaic modules. At ANU, we have produced 20% efficient Sliver solar cells using a robust, optimised cell fabrication process described in this paper. We have devised a rapid, reliable and simple method for extracting Sliver cells from a Sliver wafer, and methods for assembling modularised Sliver cell sub-modules. The method for forming these Sliver sub-modules, along with a low-cost method for rapidly forming reliable electrical interconnections, are presented. Using the sub-module approach, we describe low-cost methods for assembling and encapsulating Sliver cells into a range of module designs.

Franklin, Evan; Blakers, Andrew; Everett, Vernie; Weber, Klaus

2007-12-01

44

Solar cell window fitting  

SciTech Connect

A window fitting is described comprising: (a) a frame structure dimensioned to fit in a window opening of a building; (b) a pair of transparent panes supported by the frame structure in substantially parallel disposition with respect to each other to define a space there between; a window blind secured to the frame structure so as to be disposed in the space between the transparent panes, the window blind comprising a plurality of slats mounted in generally parallel disposition with respect to each other for substantially simultaneous rotation of the slats so that each of the slats moves through an angular range from a CLOSED configuration in which the slats overlap each other so as to block passage of sunlight through the window opening to a fully OPEN configuration in which a maximum amount of sunlight can pass through the window opening; (d) a plurality of solar-chargeable batteries for storing electrical energy, the batteries being mounted on the slats; (e) a plurality of solar cells mounted on the batteries so as to be exposed to sunlight incident upon the slats, the batteries thereby being sandwiched between the solar cells and the slats, the solar cells being electrically connected to the batteries so that the batteries can be electrically charged by the solar cells; and means for removing from the batteries the stored electrical energy that has been generated by the solar cells.

Gillard, C.W.

1993-06-22

45

Large Retractable Solar Cell Array.  

National Technical Information Service (NTIS)

Presented are detailed drawings of the orientation mechanism in corporation of reference solar cell and solar cell modules of 8 and 12-mil cells in the solar panel design, detail drawings of the drum mechanism and solar array, and all electronic circuit d...

E. O. Felkel G. Wolff

1969-01-01

46

A space-borne solar stereoscope experiment in solar physics  

NASA Astrophysics Data System (ADS)

A space experiment project is proposed, with the main purpose of obtaining 3-dimensional images of the solar atmosphere. We give a list of problems and objectives which can be resolved through the space-borne solar stereoscope.

Grigoryev, V. M.

1993-12-01

47

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

48

Terrestrial solar spectra, solar simulation and solar cell efficiency measurement  

NASA Astrophysics Data System (ADS)

Fundamentals of light transmittance and, 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. 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 betwen the spectral response of the reference cell used to set the solar simulator and that of the test cell. The ASTM terrestrial solar irradiance spectrum is recommended as a reference, spectrum and, the used either filtered xenon arc or dichroic filtered tungsten halogen lamps for solar simulation is also recommended.

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

1981-09-01

49

Parameterization of solar cells  

NASA Astrophysics Data System (ADS)

The aggregation (sorting) of the individual solar cells into an array is commonly based on a single operating point on the current-voltage (I-V) characteristic curve. An alternative approach for cell performance prediction and cell screening is provided by modeling the cell using an equivalent electrical circuit, in which the parameters involved are related to the physical phenomena in the device. These analytical models may be represented by a double exponential I-V characteristic with seven parameters, by a double exponential model with five parameters, or by a single exponential equation with four or five parameters. In this article we address issues concerning methodologies for the determination of solar cell parameters based on measured data points of the I-V characteristic, and introduce a procedure for screening of solar cells for arrays. We show that common curve fitting techniques, e.g., least squares, may produce many combinations of parameter values while maintaining a good fit between the fitted and measured I-V characteristics of the cell. Therefore, techniques relying on curve fitting criteria alone cannot be directly used for cell parameterization. We propose a consistent procedure which takes into account the entire set of parameter values for a batch of cells. This procedure is based on a definition of a mean cell representing the batch, and takes into account the relative contribution of each parameter to the overall goodness of fit. The procedure is demonstrated on a batch of 50 silicon cells for Space Station Freedom.

Appelbaum, J.; Chait, A.; Thompson, D.

1992-10-01

50

Thin film solar cells  

SciTech Connect

Written for graduate students and R and D scientists and engineers, this text provides a lucid treatment of many facets of materials, technologies, and solid-state physics of thin film solar cell devices. The various types of homo-, hetero-, barrier, and liquid junction solar cells involving amorphous, polycrystalline, and epitaxial semiconductor thin films are all covered. The volume details the basic solid-state physics of junction devices and describes thin film materials and associated preparation, measurement, and analysis techniques, as well as device technology. The authors present a critical comparative analysis of the performance of various types of thin film solar cells in order to focus on the present status of the field and to project future developments.

Chopra, K.L.; Das, S.R.

1983-01-01

51

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

52

Solar-cell panel simulator  

Microsoft Academic Search

The energy generated by solar cells can be transformed into ac power by means of inverters. In most cases these inverters cannot be tested under real conditions, since large solar-cell arrays are not yet available at reasonable prices. Therefore, a circuit that simulates a solar-cell array has been developed.

D. Baert

1979-01-01

53

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

54

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.

55

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

56

Polymer solar cells.  

PubMed

This article reviews the motivations for developing polymer-based photovoltaics and describes some of the material systems used. Current challenges are identified, and some recent developments in the field are outlined. In particular, recent work to image and control nanostructure in polymer-based solar cells is reviewed, and very recent progress is described using the unique properties of organic semiconductors to develop strategies that may allow the Shockley-Queisser limit to be broken in a simple photovoltaic cell. PMID:23816905

Greenham, Neil C

2013-07-01

57

Results from the high efficiency solar panel experiment flown on CRRES  

Microsoft Academic Search

Results from the high efficiency solar panel experiment (HESP) flown on the Combined Release and Radiation Effects Satellite (CRRES) are presented. The on-orbit solar cell degradation is correlated with the proton and electron environments. Comparisons between GaAs\\/Ge and Si solar cells are presented, and results from three different annealing methods of like GaAs solar cells are compared. Solar cell degradation

K. P. Ray; E. G. Mullen; T. M. Trumble

1993-01-01

58

Solar neutrinos: theory vs experiment.  

National Technical Information Service (NTIS)

I review the standard solar model, the disparities between its predictions and the solar neutrino flux measurements of the Homestake and Kamioka II collaborations, and possible particle physics resolutions of this puzzle. The effects of matter, including ...

W. C. Haxton

1991-01-01

59

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

60

Large Retractable Solar Cell Array.  

National Technical Information Service (NTIS)

The main activities on the Large Retractable Solar Cell Array(LRSCA) program during the fifth quarterly reporting period consisted of completion of the detailed drawings of the solar array, drum mechanism, and control electronics unit (CEU). Circuit desig...

E. O. Felkel G. Wolff M. C. Olson W. N. Turner R. E. Daniel

1969-01-01

61

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

62

Report on the Homestake solar neutrino experiment.  

NASA Astrophysics Data System (ADS)

The observations from the Homestake radiochemical solar neutrino experiment based upon the neutrino absorption process 37Cl(?e,e-)37Ar over the period 1970 to 1992 are given. The observations are compared to those from the Kamiokande II experiment, the gallium experiments and solar model calculations. A discussion is given of the question of a possible variation of the solar neutrino flux in anticorrelation with the solar activity cycle. The Homestake and Kamiokande II experiments are compared on the basis of the standard model and the flux of 8B neutrinos. There is agreement between these two experiments during the period January 1987 to May 1990 when both experiments were observing. The average 8B neutrino flux during this period was (2.2±0.2)×106cm-2sec-1. The report includes a discussion of the operation of the Homestake experiment, and the evaluations of various background processes.

Davis, R., Jr.

63

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

64

Solar neutrino experiments : past, present and future  

Microsoft Academic Search

Solar neutrino detection started 25 years ago by the famous radiochemical chlorine experiment installed by Davis and his collaborators (600 tons of C_2Cl_4 in the Homestake mine, South Dakota). Neutrinos produce radioactive (37) Ar atoms (T_{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(-36) capture\\/atom\\/second) and

D. Vignaud

1993-01-01

65

Amorphous silicon solar cells  

NASA Astrophysics Data System (ADS)

The photoconductive response of Schottky-barrier and p-i-n solar cell structures was analyzed. It shows that the photoconductivity determines the fill factor, rather than the dark current, as in crystalline silicon cells. An analysis of the I-V curves of p-i-n cells shows that the electron and hole drift lengths are comparable. High conductivity p and n type films (sigma = 1-10 (LAMBDA) (+1).cm(+1)) were produced in an rf discharge for T/sub s/ 4000 C and in a dc cathodic discharge for T/sub s/ 3500 C. Diffusion lengths of approx. 0.8 (SIGMA)m were measured in undoped a-Si:H films at illumination levels of approx. 0.1 Sun. The activation energy of the diffusion length is 0.28 eV. The technique for measuring the diffusion length was improved by a liquid Schottky-barrier contact. It is confirmed that carbon alloying of the p layer improves the performance of p-i-n cells illuminated through that layer and also that the stability is better for cells illuminated through the p layer. It is indicated that a major factor determining the efficiency of ITO/n-i-p cells is the ITC/n contact. Several parameters were determined that affect device stability. A gradual boron profile enhances stability, as does a thin, undoped layer. Increased oxygen contamination increases the degradation of a-Si:H p-i-n cells.

Carlson, D. E.; Crandall, R. S.; Dresner, J.; Goldstein, D.; Hanak, J. J.; Moore, A. R.; Schade, R. E.; Staebler, D. L.; Weakliem, H. A.; Williams, R.

1981-05-01

66

SPDE: Solar Plasma Diagnostic Experiment  

NASA Astrophysics Data System (ADS)

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.

1995-09-01

67

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

2012-08-16

68

Solar Neutrinos: Real-Time Experiments.  

National Technical Information Service (NTIS)

This report outlines the principle of real-time solar neutrino detection experiments by detecting electrons with suitable target material, via Charged-Current (CC) reaction using conventional counting techniques developed in high-energy physics. Only B-8 ...

Y. Totsuka

1993-01-01

69

An Introduction to Solar Cells  

ERIC Educational Resources Information Center

|Most likely, solar cells will play a significant role in this country's strategy to address the two interrelated issues of global warming and dependence on imported oil. The purpose of this paper is to present an explanation of how solar cells work at an introductory high school, college, or university physics course level. The treatment…

Feldman, Bernard J.

2010-01-01

70

Flexible solar cells for clothing  

Microsoft Academic Search

Integration of flexible solar cells into clothing can provide power for portable electronic devices. Photovoltaics is the most advanced way of providing electricity far from any mains supply, although it suffers from the limits of ambient light intensity. But the energy demand of portable devices is now low enough that clothing-integrated solar cells are able to power most mobile electronics.

Markus B. Schubert; Jürgen H. Werner

2006-01-01

71

Colloidal quantum dot solar cells  

NASA Astrophysics Data System (ADS)

Solar cells based on solution-processed semiconductor nanoparticles -- colloidal quantum dots -- have seen rapid advances in recent years. By offering full-spectrum solar harvesting, these cells are poised to address the urgent need for low-cost, high-efficiency photovoltaics.

Sargent, Edward H.

2012-03-01

72

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

73

Lunar production of solar cells  

NASA Astrophysics Data System (ADS)

The feasibility of manufacturing of solar cells on the moon for spacecraft applications is examined. Because of the much lower escape velocity, there is a great advantage in lunar manufacture of solar cells compared to Earth manufacture. Silicon is abundant on the moon, and new refining methods allow it to be reduced and purified without extensive reliance on materials unavailable on the moon. Silicon and amorphous silicon solar cells could be manufactured on the moon for use in space. Concepts for the production of a baseline amorphous silicon cell are discussed, and specific power levels are calculated for cells designed for both lunar and Earth manufacture.

Landis, Geoffrey A.; Perino, Maria Antonietta

1989-05-01

74

Thin Film Solar Cell Workshop.  

National Technical Information Service (NTIS)

A summation of responses to questions posed to the thin-film solar cell workshop and the ensuing discussion is provided. Participants in the workshop included photovoltaic manufacturers (both thin film and crystalline), cell performance investigators, and...

J. Armstrong F. Jeffrey

1993-01-01

75

Updated Review of Solar Models and Solar Neutrino Experiments  

NASA Astrophysics Data System (ADS)

The Conventional Wisdom that there is a Solar Neutrino Problem and that New Physics is required, is examined. The various solar evolutionary models, (or SSM), are described and in particular the four new 1992 papers. While the evolutionary models are generally robust, there are important assumptions and uncertainties (screening, nuclear reaction rates, etc.) which mean that the errors cannot be small. Diffusion in the Sun is expected to be significant but so far there is no calculation which includes all types of diffusion, especially turbulent diffusion. The new and important helioseismological results are shown to to be in agreement with some of the SSM calculations. The experimental results are beginning to be not inconsistent with the SSM calculations. Kamiokande is consistent with SSM calculations except for one with rather small errors. The new GALLEX result is in agreement with all SSM calculations within 1.3 to 2 standard deviations. The 1990 SAGE I experiment is shown to have no evidence of solar neutrinos and is inconsistent with all SSM calculations and with GALLEX. However the new 1991 SAGE II experiment finds neutrino rates not inconsistent with SSM calculations. The Chlorine experiment is significantly below SSM calculations and is inconsistent with Kamiokande. In particular the Chlorine claim that there is a variation of the solar neutrino flux with the inverse of the sunspot activity, which shows a correlation of five standard deviation significance, is in contradiction with the results of the Kamiokande experiment which finds no variation of the solar neutrino flux with time. The overall conclusion is that there is no compelling evidence for a Solar Neutrino Problem or need for New Physics. However the neutrinos could still have masses and further experiments with higher statistics are essential as they are one of the rare ways of studying this low mass region. Thus the Solar Neutrino Problem is becoming a Neutrino Mass Quest.

Morrison, Douglas R. O.

76

The Galileo solar redshift experiment  

NASA Astrophysics Data System (ADS)

From the October 1989 launch to the first December 1990 earth gravity assist, we regularly obtained frequency measurements of the spacecraft clock - an ultrastable crystal oscillator (USO) supplied by Frequency Electronics, Inc. The solar gravitational redshift in frequency was readily detectable, and because of the unique variations in heliocentric distance we could separate the general relativistic effects from the USO's intrinsic frequency variations. We have verified the total frequency shift predicted by general relativity to 0.5 percent accuracy, and the solar gravitational redshift to 1 percent accuracy.

Krisher, Timothy P.; Morabito, David D.; Anderson, John D.

1993-04-01

77

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, and some proposals for direct counting 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.

1984-01-01

78

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

79

Germanium Nanocrystal Solar Cells  

NASA Astrophysics Data System (ADS)

Greenhouse gas concentrations in the atmosphere are approaching historically unprecedented levels from burning fossil fuels to meet the ever-increasing world energy demand. A rapid transition to clean energy sources is necessary to avoid the potentially catastrophic consequences of global warming. The sun provides more than enough energy to power the world, and solar cells that convert sunlight to electricity are commercially available. However, the high cost and low efficiency of current solar cells prevent their widespread implementation, and grid parity is not anticipated to be reached for at least 15 years without breakthrough technologies. Semiconductor nanocrystals (NCs) show promise for cheap multi-junction photovoltaic devices. To compete with photovoltaic materials that are currently commercially available, NCs need to be inexpensively cast into dense thin films with bulk-like electrical mobilities and absorption spectra that can be tuned by altering the NC size. The Group II-VI and IV-VI NC communities have had some success in achieving this goal by drying and then chemically treating colloidal particles, but the more abundant and less toxic Group IV NCs have proven more challenging. This thesis reports thin films of plasma-synthesized Ge NCs deposited using three different techniques, and preliminary solar cells based on these films. Germanium tetrachloride is dissociated in the presence of hydrogen in a nonthermal plasma to nucleate Ge NCs. Transmission electron microscopy and X-ray diffraction indicate that the particles are nearly monodisperse (standard deviations of 10-15% the mean particle diameter) and the mean diameter can be tuned from 4-15 nm by changing the residence time of the Ge NCs in the plasma. In the first deposition scheme, a Ge NC colloid is formed by reacting nanocrystalline powder with 1-dodecene and dispersing the functionalized NCs in a solvent. Films are then formed on substrates by drop-casting the colloid and allowing it to dry. As-deposited films are electrically insulating due to the long hydrocarbon molecules separating neighboring particles; however, mass spectrometry shows that annealing treatments successfully decompose these molecules. After annealing at 250 °C, Ge NC films exhibit conductivities as large as 10-6 S/cm. In the second film deposition scheme, a Ge NC colloid is formed by dispersing Ge NCs in select solvents without further surface modification. While these "bare" NCs quickly agglomerate and flocculate in nearly all non-polar solvents, they remain stable in benzonitrile and 1,2-dichlorobenzene, among others. Thin-film field-effect transistors have been fabricated by spinning Ge NC colloids onto substrates and the films have been subjected to various annealing procedures. The devices show n-type, p -type, or ambipolar behavior depending on the annealing conditions, with Ge NC films annealed at 300°C exhibiting electron saturation mobilities greater than 10-2 cm2/Vs and on-to-off ratios of 104. The final film deposition scheme involves the impaction of Ge NCs onto substrates downstream of the synthesis plasma via acceleration of the NCs through an orifice. This technique produces highly uniform films with densities greater than 50% of the density of bulk Ge. By varying the size of the Ge NCs, we have measured films with band gaps ranging from the bulk value of 0.7 eV to over 1.1 eV for films of 4 nm Ge NCs. Having deposited dense thin films with tunable band gaps and respectable mobilities, we have begun fabricating bilayer solar cells consisting of heterojunctions between Ge NC films and P3HT, Si NCs, or Si wafers. Preliminary devices exhibit opencircuit voltages and short-circuit currents as large as 0.3 V and 4 mA/cm 2, respectively.

Holman, Zachary Charles

80

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

81

Experiences in solar cooling systems  

NASA Astrophysics Data System (ADS)

Six of the nine solar cooling systems discussed in this paper had negative energy savings. In several cases the solar cooling system used substantially more energy than a conventional system could have been expected to use. Two systems, however, had significant energy savings. These systems (1 residential and 1 commercial) obtained system thermal efficiencies of 12.0 to 12.4 percent. Their system overall efficiences averaged 11.2 and 5.2 percent respectively. The residential-sized system achieved an annual energy savings of about 16.8 GJ/year, or approximately .34 GJ/year.m2 of collector. The commercial system had equivalent values of 137 GJ/year or about .22 GJ/year/sq m of collector. It should be noted that these efficiencies re much lower than those of well-designed and properly controlled cooling systems in commercial sizes. However, with realistic system modifications and subsequent improvements in performance these solar cooling systems can be expected to achieve savings in nonrenewable energy sources of approximately 1.2 GJ/year/sq m of collector. These savings can be compared to those associated with solar space and domestic hot water heating systems of 2.2 and 2.5 GJ/year/sq m of collector, respectively.

Ward, D. S.; Oberoi, H. S.

82

Voltage-dependent photocurrent transients of PTB7:PC70BM solar cells: Experiment and numerical simulation  

NASA Astrophysics Data System (ADS)

Transient photocurrent measurements on efficient polymer/fullerene solar cells based on a blend of the donor polymer PTB7 with the fullerene acceptor PC70BM are reported. In particular, we examine the light intensity dependence and voltage dependence of the turn-on and turn-off photocurrent dynamics of devices in response to a 200 ?s square light pulse. At short circuit, subtle changes in the turn-on and turn-off dynamics are observed consistent with charge-density-dependent transport phenomena. As the working voltage is moved from short circuit to open circuit, we observe the appearance of an initial transient photocurrent peak a few microseconds after turn-on before the device settles to steady state. Furthermore, we observe only a weak dependence of the charge extraction dynamics on the working voltage, with the amount of charge extracted monotonically decreasing as the working voltage is moved from short circuit to open circuit. This collection of features is interpreted with the aid of numerical simulations in terms of charge trapping, with increased trap-assisted recombination closer to open circuit. The operation of devices fabricated with and without the solvent additive di-iodooctane is also compared. Charge trapping features are reduced for optimized devices fabricated with the solvent additive compared to devices fabricated without. The use of the solvent additive di-iodooctane in this system is therefore important in minimizing trap-assisted recombination.

Li, Zhe; Lakhwani, Girish; Greenham, Neil C.; McNeill, Christopher R.

2013-07-01

83

Lithium counterdoped silicon solar cell  

Microsoft Academic Search

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

I. Weinberg; H. W. Brandhorst Jr.

1986-01-01

84

Lithium counterdoped silicon solar cell  

Microsoft Academic Search

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

I. Weinberg; Brandhorst H. W. Jr

1984-01-01

85

Experiences in solar cooling systems  

NASA Astrophysics Data System (ADS)

The results of performance evaluations for nine solar cooling systems are presented, and reasons fow low or high net energy balances are discussed. Six of the nine systems are noted to have performed unfavorably compared to standard cooling systems due to thermal storage losses, excessive system electrical demands, inappropriate control strategies, poor system-to-load matching, and poor chiller performance. A reduction in heat losses in one residential unit increased the total system efficiency by 2.5%, while eliminating heat losses to the building interior increased the efficiency by 3.3%. The best system incorporated a lithium bromide absorption chiller and a Rankine cycle compression unit for a commercial application. Improvements in the cooling tower and fan configurations to increase the solar cooling system efficiency are indicated. Best performances are expected to occur in climates inducing high annual cooling loads.

Ward, D. S.

86

SPDE: Solar Plasma Diagnostic Experiment  

Microsoft Academic Search

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

Marilyn E. Bruner

1995-01-01

87

Report on solar-neutrino experiments  

SciTech Connect

This report on solar neutrino experiments will include a summary of the results of the chlorine detector, and an account of our plans to build a gallium solar neutrino experiment. In addition to discussing the experimental side of the solar neutrino problem I would like to relate our experiences during the last 15 years in working in the Homestake Gold Mine. In the course of our work at Homestake a number of independent groups have asked to use our facilities and, because of the cooperative and helpful attitude of the Mine management, these experimentalists could be easily accommodated. A brief account of these experiences may be 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.

1982-01-01

88

Solar Energy Experiment for Beginning Chemistry.  

ERIC Educational Resources Information Center

Describes an experiment illustrating how such chemical concepts as light absorption, thermodynamics, and solid-state photovoltaics can be incorporated into solar energy education. Completed in a three-hour period, the experiment requires about two hours for data collections with the remaining hour devoted to calculations and comparison of results.…

Davis, Clyde E.

1983-01-01

89

MSW effect and solar neutrino experiments  

SciTech Connect

We describe the MSW solutions to the /sup 37/Cl solar neutrino experiment, and their implications for the /sup 71/Ga experiment. Measurement of the spectrum of electron-type neutrinos arriving at earth is emphasized. 8 refs., 2 figs., 1 tab.

Rosen, S.P.

1986-01-01

90

Panel for solar energy cells  

Microsoft Academic Search

A panel for mounting solar energy cells, and particularly those cells upon which light is to be concentrated, includes an enclosure for holding the cells and has at least one wall formed from a good conductor of heat. The cells are mounted within the enclosure on a resinous cushion that is a relatively good conductor of heat and a poor

Varadi

1977-01-01

91

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

92

Large Retractable Solar Cell Array.  

National Technical Information Service (NTIS)

The main activity on the Large Retractable Solar Cell Array (LRSCA) program during the third quarterly reporting period consisted of the completion of the analysis of a majority of the major subsystem components, start of detailed drawings, completion of ...

G. Wolff E. O. Felkel

1969-01-01

93

Lithium Implanted Solar Cells, Data.  

National Technical Information Service (NTIS)

The report contains the identification and processing description of all samples processed and the tabulated measurement data obtained on phosphorus diffused, lithium implanted, p-type silicon solar cell blanks. (Author)

D. A. Smith J. L. Hartke

1973-01-01

94

Thin-film solar cells  

Microsoft Academic Search

The rapid progress that is being made with inorganic thin-film photovoltaic (PV) technologies, both in the laboratory and in industry, is reviewed. While amorphous silicon based PV modules have been around for more than 20 years, recent industrial developments include the first polycrystalline silicon thin-film solar cells on glass and the first tandem solar cells based on stacks of amorphous and

Armin G. Aberle

2009-01-01

95

CCMR: Nanocrystal Sensitized Solar Cells  

NSDL National Science Digital Library

Nanocrystal sensitized solar cells demonstrate a possible cheap solution to practical device manufacture. This research examined the feasibility of using lead sulfide nanocrystals to sensitize tin dioxide and titanium dioxide substrates for the purpose of making a functioning photovoltaic device. Challenges included optimizing the substrate materials as well as the thin films made from them. Results indicate that titanium dioxide produces more suitable thin films than tin dioxide. Also, the methods employed did produce a functioning solar cell after optimization.

Perry, Alexis

2009-08-15

96

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

97

The Cassini Solar Faraday Rotation experiment  

NASA Astrophysics Data System (ADS)

The Cassini Solar Faraday Rotation Experiment took place during the Cassini solar conjunctions in 2002 and 2003. One hundred and sixty hours of open-loop radioscience data were collected in the 8 and 32 GHz frequencies (X- and Ka-bands). These frequencies are both much higher than the plasma frequencies in the corona, but sufficiently low to undergo measurable Faraday rotation in the solar corona. During the 2002 experiment, four Coronal Mass Ejections crossed the signal between Cassini and the Earth. Each Coronal Mass Ejection crossing was different. The first occurred during the day of conjunction when the spacecraft's signal passed within approximately 2 solar radii of the center of the sun. The second occurred 1 day later when the closest approach of the signal had moved to 3 solar radii. This event was oriented almost perpendicular to the first as shown by the SOHO EIT imager. It had a significant impact on the signal, causing the Ka-band transmitter on Cassini to lose lock on the Earth one roundtrip light time later. The 3rd and 4th CMEs occurred 2 days later as a paired event when the line of sight to Cassini came as close as 5 solar radii. During the 2003 experiment, the line of sight from Cassini to the Earth passed within 1.25 solar radii of the center of the sun. The received data is highly variable and constitutes the closest radio occultation measurement to the surface of the sun. We discuss the Cassini Faraday Rotation data, the deduced electron densities and the magnetic fields required to produce the measured Faraday rotations.

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

98

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

Microsoft Academic Search

The space environment in earth orbit has been extensively studied and documented. The most serious factors influencing electrical systems (including solar arrays) are the local radiation environment, thermal cycling effects, local plasma density, neutral particle density, spacecraft surfaces outgassing\\/effuent products, and the meteroid and debris flux. The radiation environment (proton, electron, and photon), fueled primarily by the sun but also

David C. Hill; M. Frank Rose

1994-01-01

99

Terrestrial concentrator solar cell module  

SciTech Connect

This patent describes a solar cell module having a plurality of discrete cell units wherein each cell unit constitutes a tandem cell comprising an upper cell of a first semiconductive material and a lower cell of a second semiconductive material. It comprises a housing having a base and an upper portion; primary outer lens elements supported by the housing upper portion; a secondary radiant energy concentrating element associated with each primary lens element for protecting the carrier tape against incident light; each of the solar cell units being thermally coupled to the base; and parallel spaced strips of conductive material carried by the tape with means for separately connecting the strips to predetermined contact surfaces of the upper and lower cells of each cell unit.

Fraas, L.M.; Mansoori, N.; Kim, N.B.; Avery, J.E.

1992-06-02

100

Interdigitated back contact solar cells  

NASA Astrophysics Data System (ADS)

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 and in the back surface field regions is given. This discussion covers the questions of: how to handle degeneracy, how to compute carrier concentrations in the absence of knowledge of the details of the band structure under heavily doped conditions, and how to reconcile the usual interpretation of heavy doping as a rigid shift of the bands with the band tailing and impurity level conduction models. It also discusses the reasons for the observed discrepancies between various experimental measurements of bandgap narrowing.

Lundstrom, M. S.; Schwartz, R. J.

1980-08-01

101

Lithium counterdoped silicon solar cell  

SciTech Connect

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. NASA

Weinberg, I.; Brandhorst, H.W., Jr.

1984-11-01

102

Lithium Counterdoped Silicon Solar Cell.  

National Technical Information Service (NTIS)

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. T...

I. Weinberg H. W. Brandhorst

1984-01-01

103

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.

104

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

105

Reverse bias degradation in dye solar cells  

NASA Astrophysics Data System (ADS)

A prolonged reverse bias (RB) stress forcing a short-circuit current through a dye solar cell, corresponding to the harshest test a shadowed cell may experience in real conditions, can cause the RB operating voltage VRB to drift with time, initially slowly but accelerating for VRB < (-1.65 +/- 0.15)V when gas bubbles, identified as H2 (gas chromatography), are produced inside the cell, leading to breakdown. A close connection between VRB, cell performance, and stability was established. Contributions to RB degradation include triiodide depletion and impurities, in particular water. Acting upon these components and setting up protection strategies is important for delivering long-lasting modules.

Mastroianni, Simone; Lanuti, Alessandro; Brown, Thomas M.; Argazzi, Roberto; Caramori, Stefano; Reale, Andrea; Di Carlo, Aldo

2012-09-01

106

Photon upconversion for thin film solar cells  

Microsoft Academic Search

In this research one of the many possible methods to increase the efficiency of solar cells is described. The method investigated is based on adapting the solar light in such a way that the solar cell can convert more light into electricity. The part of the solar spectrum that is adapted is the part that cannot be absorbed by the

J. de Wild

2012-01-01

107

Investigation of Sustained Arc under Solar Cell  

Microsoft Academic Search

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

Kazuhiro Toyoda; Mengu Cho; Shirou Kawakita; Masato Takahashi

2010-01-01

108

Development of concentrator solar cells  

SciTech Connect

A limited pilot production run on PESC silicon solar cells for use at high concentrations (200 to 400 suns) is summarized. The front contact design of the cells was modified for operation without prismatic covers. The original objective of the contract was to systematically complete a process consolidation phase, in which all the, process improvements developed during the contract would be combined in a pilot production run. This pilot run was going to provide, a basis for estimating cell costs when produced at high throughput. Because of DOE funding limitations, the Photovoltaic Concentrator Initiative is on hold, and Applied Solar`s contract was operated at a low level of effort for most of 1993. The results obtained from the reduced scope pilot run showed the effects of discontinuous process optimization and characterization. However, the run provided valuable insight into the technical areas that can be optimized to achieve the original goals of the contract.

Not Available

1994-08-01

109

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

110

SNO and future solar neutrino experiments  

NASA Astrophysics Data System (ADS)

The SNO Collaboration has completed a combined analysis of 8B solar neutrino data from all three phases of the project. The combined analysis resulted in a total flux of active neutrino flavors from 8B decays in the sun of 5.25±0.16(stat.)?0.13+0.11(syst.)×106. A three-flavor neutrino oscillation analysis combining the SNO results with results of all other solar neutrino experiments and the KamLAND experiment yielded ?m212=(7.41?0.19+0.21)×10?5, tan2?12=0.446?0.029+0.030, and sin2?13=(2.5?1.5+1.8)×10?2. The results of the SNO analysis will be presented, along with a discussion of future projects that will seek to study lower energy neutrinos to improve on our knowledge of the properties of neutrinos and the sun.

McDonald, A. B.

2013-02-01

111

Solar neutrinos: Real-time experiments  

Microsoft Academic Search

This report outlines the principle of real-time solar neutrino detection experiments by detecting electrons with suitable target material, via Charged-Current (CC) reaction using conventional counting techniques developed in high-energy physics. Only B-8 neutrinos can be detected by minimum detectable energy of several MeV. The MSW (Mikheyev, Smirnov, Wolfenstein) effect not only distorts the energy spectrum but also induces new type

Yoji Totsuka

1993-01-01

112

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

113

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

114

Solar cell fabrication studies pertinent to developing countries  

SciTech Connect

The question of photovoltaics among the many approaches to the energy problem as being of relevance in the Third World countries is discussed. Based on these studies, which involved the physics of solar cells, various solar cell configurations, the materials for their fabrication and their fabrication sequences, it was concluded that silicon homojunction solar cells are best suited to the present needs and environment of, and suitable for development in the Third World. The cadmium sulphide-cuprous sulphide solar cell could be considered as a viable future candidate. Attendant with the adoption of photovoltaics as electric energy supply, is the problem of technology transfer and development. Towards that goal, laboratory studies were carried out on the fabrication of solar cells using very simple fabrication sequences and materials to demonstrate the tolerable efficiencies are achievable by their use. To demonstrate how basic research could benefit solar cell fabrication, a number of experiments were undertaken; such as varying fabrication sequences and materials, finding their radiation tolerance, and carrying out Deep Level Transient Spectroscopy (DLTS) studies, in an attempt to understand some of the fabrication and environmental factors which limit solar cell performance. It was found that subjecting wafers to preheat treatments does not improve solar cell performance, but rather reduces solar cell radiation tolerance. Also P-type substrate solar cells were found to be more radiation resistant than N-type substrate solar cells. The Deep Level Transient Spectroscopy results showed that carbon and oxygen, as one would expect, are chief contaminants of the silicon wafers that were used in the fabrication of the solar cells.

Prah, J.H.

1983-01-01

115

Solar cell array  

Microsoft Academic Search

An array of photovoltaic cells in a back wall-type configuration supported by a rigid transparent vitreous substrate, such as glass, for admitting incident radiation to the cells is described. A plurality of cells are interconnected into a desired electrical configuration by one or more layers of electrically conducting materials which overlie the entire heterojunction of each cell to minimize the

J. F. Jordan; C. M. Lampkin

1982-01-01

116

Solar cell array  

Microsoft Academic Search

An array of photovoltaic cells in a back wall-type configuration supported by a rigid transparent vitreous substrate, such as glass, for admitting incident radiation to the cells is described. A plurality of cells are interconnected into a desired electrical configuration by one or more layers of electrically conducting materials which overlie substantially the entire heterojunction of each cell to minimize

J. F. Jordan; C. M. Lampkin

1981-01-01

117

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

118

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

119

Titania solar cells: new photovoltaic technology  

Microsoft Academic Search

Titania solar cells are a new type of photovoltaic device invented by Professor Michael Grätzel at Ecole Polytechnique Federale de Lausanne (Switzerland). Titania solar cells convert sunlight directly into electricity through a process similar to photosynthesis. It has performance advantages over other solar cells, which include the ability to perform well in low light and shade, and to perform consistently

George Phani; Gavin Tulloch; David Vittorio; Igor Skryabin

2001-01-01

120

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

121

Concentrator solar cell array module  

Microsoft Academic Search

A concentrator solar cell array module is described having a metallic heat sink with a planar mounting surface. A semiconductor spacer is provided. The semiconductor spacer is provided with a layer of insulating material in the form of silicon oxide. The silicon oxide surface is secured to the mounting surface of the heat sink by a thermally conductive adhesive. A

R. M. Diamond; K. S. Ling; A. G. Winterer

1979-01-01

122

Experiments on a new small-scale solar dryer  

Microsoft Academic Search

A new solar dryer, which consisted of a solar air heater and a drying chamber, was developed for drying food products. The present drying system was successfully tested using sultana grapes, green beans, sweet peppers and chilli peppers. The traditional sun-drying experiments were employed and compared with the solar-drying experiments. It was shown that the use of this type of

Cigdem Tiris; Mustafa Tiris; Ibrahim Dincer

1996-01-01

123

A novel chlorophyll solar cell  

NASA Astrophysics Data System (ADS)

The photosynthetic process is reviewed in order to produce a design for a chlorophyll solar cell. In a leaf, antenna chlorophyll absorbs light energy and conducts it to an energy trap composed of a protein and two chlorophyll molecules, which perform the oxidation-reduction chemistry. The redox potential of the trap changes from 0.4 to -0.6 V, which is sufficient to reduce nearby molecules with redox potentials in that range. The reduction occurs by transfer of an electron, and a chlorophyll solar cell would direct the transferred electron to a current carrier. Chlorophyll antenna and traps are placed on a metallic support immersed in an electron acceptor solution, and resulting electrons from exposure to light are gathered by a metallic current collector. Spinach chlorophyll extracted, purified, and applied in a cell featuring a Pt collector and an octane water emulsion resulted in intensity independent voltages.

Ludlow, J. C.

124

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

125

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

126

Solar cell calibration by balloon flight  

Microsoft Academic Search

An overview of the manufacture and calibration by balloon flight of primary standard solar batteries is presented as follows. Primary standard solar battery cells of micro N electrode Back Surface Reflector (BSR) and micro N electrode Back Surface Field and Reflector (BSFR) type were produced, and primary solar battery modules of both types were assembled each with four cells selected

Sumio Matsuda; Takashi Tamura; Masato Uesugi

1992-01-01

127

Solar cell junction processing system  

Microsoft Academic Search

An integrated system and process for the continuous formation of p-n junctions in solar cells in a cost-effective manner and under computer control. The integrated system essentially comprises an ion beam implanter, an electron beam annealer and a combination vacuum lock-and-wafer transport system, all disposed within a unitary housing maintained under a common vacuum environment. The integrated system employs no

A. J. Armini; R. G. Little

1982-01-01

128

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

129

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

130

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

131

Microwave solar radar experiment. I. Observations  

SciTech Connect

This is a report on the first solar radar experiment in microwaves. It was carried out with the 300 m dish in Arecibo using a 250 kW transmitter. Receiving at a displaced frequency from the transmitted radar frequency allowed us to probe the Langmuir (plasma) wave energy density of the corona in the 170--270 MHz range. We have not found any echo in various regions on the Sun: quiet regions, active regions, type I radio sources and even a possible type IV radio source. This contradicts some models of type I radio bursts and a proposed scattering mechanism of metric solar radar echos. An alternative experiment, in which we received at the transmitted frequency, did not produce any echo either. The reflectivity of the Sun in microwaves is more than four orders of magnitude below the reflectivity in meter waves. In the second paper of this series, upper limits on Langmuir wave densities will be calculated from these results for the various pointing positions.

Fitze, H.R.; Benz, A.O.

1981-11-15

132

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

133

Solar neutrinos: Real-time experiments  

NASA Astrophysics Data System (ADS)

This report outlines the principle of real-time solar neutrino detection experiments by detecting electrons with suitable target material, via Charged-Current (CC) reaction using conventional counting techniques developed in high-energy physics. Only B-8 neutrinos can be detected by minimum detectable energy of several MeV. The MSW (Mikheyev, Smirnov, Wolfenstein) effect not only distorts the energy spectrum but also induces new type of neutrinos, i.e. mu-neutrinos or tau-neutrinos. These neutrinos do not participate in the CC reaction. Therefore real-time experiment is to be sensitive to Neutral Current (NC) reactions. It is a challenge to eliminate environment background as much as possible and to lower the minimum detectable energy to several 100 keV, which will enable observation of Be-7 neutrinos. Target particles of real-time experiments currently running and under construction or planning are electron, deuteron, or argon. The relevant reactions corresponding to CC reaction and some relevant comments on the following targets are described: (1) electron target; (2) deuteron target; and (3) argon target. On-going experiment and future experiments for real-time neutron detection are also outlined.

Totsuka, Yoji

1993-04-01

134

Silicon concentrator solar cell development  

NASA Astrophysics Data System (ADS)

This project involved the development and supply of 550 silicon concentrator solar cells for use in prototype point-focus concentrator modules. The cells were to have a designed illumination area of 12.5 by 12.5 mm and to be designed for use with prismatic covers at a geometric concentration ratio of 200X. The target efficiency of 24 percent was comfortably exceeded, with efficiencies as high as 25.2 percent reached in the designed concentration ratio range. A combined lens/cell efficiency of 24.4 percent was measured at Sandia using a cell supplied during this project and a point focus Fresnel lens. Subsequently, a peak module efficiency of 20.3 percent was achieved at Sandia using 12 cells and lenses. This is believed to be the first photovoltaic module to surpass the 20 percent efficiency milestone.

Green, Martin A.; Jianhua, Zhao; Aihua, Wang; Blakers, A. W.

1990-05-01

135

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

136

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

137

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

138

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

139

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

140

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

141

New materials for nanocrystal solar cells  

Microsoft Academic Search

New organic and inorganic materials for nanocrystal solar cells are reported with descriptions and basic characterization of their applicability. Brief background is presented regarding the fundamental operation of nanocrystal-polymer solar cells as context for the body of this work. New colloidal nanocrystals synthesized for solar cells include CdTe tetrapods for improved light absorption and electron transport, and Type II core\\/shell

Delia Jane Milliron

2004-01-01

142

Interdigitated Back Contact Solar Cells. Annual Report.  

National Technical Information Service (NTIS)

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 ...

M. S. Lundstrom R. J. Schwartz

1980-01-01

143

The MIS and MISIM solar cell  

Microsoft Academic Search

The insertion of a very thin insulating layer (less than 20 A) between the metal and the semiconductor of a Schottky solar cell can dramatically improve the open circuit voltage of the cell. The resulting MIS structure is shown to be electronically equivalent to a p-n junction device, provided that minority current flow is dominant. The MISIM solar cell, a

M. A. Green; R. B. Godfrey

1978-01-01

144

Interconnect for electrically connecting solar cells  

SciTech Connect

This paper describes a solar cell array. It comprises: solar cells arranged in an array, each the solar cell having an upper electrical contact and a lower electrical contact; interconnects for electrically connecting the solar cells, each the interconnect comprising: a stress relief part comprised of a single longitudinally extended member having a central portion and first and second end portions defining a planar surface; a first connecting part attached to the upper contact of a respective one of the solar cells; a second connecting part attached to the lower contact of a solar cell adjacent to the respective one of the solar cells; means for joining the first and second connecting parts to respective first and second end portions of the stress relief part such that the central portion of the stress relief part is disposed substantially parallel to adjacent edges of the solar cells which are electrically connected by the interconnect and such that the planar surface defined by the stress relief part extends substantially perpendicularly relative to the top surface of the solar cell array.

Gaddy, E.M.

1991-04-09

145

Very High Efficiency Solar Cell Modules  

SciTech Connect

The Very High Efficiency Solar Cell (VHESC) program is developing integrated optical system - PV modules for portable applications that operate at greater than 50% efficiency. We are integrating the optical design with the solar cell design, and have entered previously unoccupied design space. Our approach is driven by proven quantitative models for the solar cell design, the optical design, and the integration of these designs. Optical systems efficiency with an optical efficiency of 93% and solar cell device results under ideal dichroic splitting optics summing to 42.7 {+-} 2.5% are described.

Barnett, A.; Kirkpatrick, D.; Honsberg, C.; Moore, D.; Wanlass, M.; Emery, K.; Schwartz, R.; Carlson, D.; Bowden, S.; Aiken, D.; Gray, A.; Kurtz, S.; Kazmerski, L., et al

2009-01-01

146

Luminescence radiation spectroscopy of silicon solar cells  

NASA Astrophysics Data System (ADS)

At present there are known many of diagnostic methods of detection large crystal lattice defects of silicon solar cells. This paper deals about results of new potential in to use one of characteristics luminescence radiation for detection defects of solar cells. So polarization spectroscopy of defect in solar cells may be used to fitting characterization of silicon solar cells. And this can lead to understand the electrical properties of defects in silicon solar cells and study of really formation defects. We used extending existing electroluminescence technology about polarization spectroscopy to yield the polarization of luminescence radiation by defect in solar cells. Radiation emitted by the solar cell has a wave character that can interact with the silicon structures or hypothetically thin reflectance layer of solar cells. In our research we can observed the linear partially polarization luminescence light on poly-silicon crack defect. Spectral response of using CCD camera is approximately 300 to 1100 nm. Sinusoid dependence of luminescence intensity on the angle of linear polarization analyzer rotation shown this fact. The degree of polarization depends on the material, in this case the character of defect. Polarized light can be obtained in various ways. This fact opens up for potential next new questions in this widely course of study diagnostics defects silicon solar cells.

Stojan, R.; Van?k, J.; Malý, M.; Gvritishvili, R.; Tománek, P.; Frantík, O.

2013-09-01

147

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

148

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

2011-08-11

149

Lithium counterdoped silicon solar cell  

SciTech Connect

A radiation damage resistant solar cell is described comprising a wafer of p-type boron doped silicon having lithium ions implanted therein in small enough quantities such that the wafer remains p-type after lithium addition. The wafer has an n/sup +/ region formed by phosphorus ions implanted therein adjacent to a surface of the wafer, a first electrical contact on the surface adjacent to the n/sup +/ region, and a second electrical contact on an opposite surface of the wafer.

Weinberg, I.; Brandhorst, H.W. Jr.

1986-08-26

150

Improved monolithic tandem solar cell  

DOEpatents

A single-crystal, monolithic, tandem, photovoltaic solar cell is described which includes (a) an InP substrate having upper and lower surfaces, (b) a first photoactive subcell on the upper surf ace of the InP substrate, (c) a second photoactive subcell on the first subcell; and (d) an optically transparent prismatic cover layer over the second subcell. The first photoactive subcell is GaInAsP of defined composition. The second subcell is InP. The two subcells are lattice matched.

Wanlass, M.W.

1991-04-23

151

SORCE: Solar Radiation and Climate Experiment.  

National Technical Information Service (NTIS)

Contents include the following: Understanding the Sun's influence on the Earth; How the Sun affect Earth's climate; By how much does the Sun's radiation very; Understanding Solar irradiance; History of Solar irradiance observations; The SORCE mission; How...

R. Cahalan G. Rottman

2002-01-01

152

Solar cell calibration facility validation of balloon flight data: A comparison of shuttle and balloon flight results  

Microsoft Academic Search

The Solar Cell Calibration Facility (SCCF) experiment was designed and built to evaluate the effect of the Earth's upper atmosphere on the calibration of solar cell standards. During execution of the experiment, a collection of carefully selected solar cells was flown on the shuttle, and reflown on a high-altitude balloon, then their outputs were compared. After correction to standard temperature

B. E. Anspaugh; R. G. Downing; L. B. Sidwell

1985-01-01

153

Leveraging the Experimental Method to Inform Solar Cell Design  

ERIC Educational Resources Information Center

|In this article, the underlying logic of experimentation is exemplified within the context of a photoelectrical experiment for students taking a high school engineering, technology, or chemistry class. Students assume the role of photochemists as they plan, fabricate, and experiment with a solar cell made of copper and an aqueous solution of…

Rose, Mary Annette; Ribblett, Jason W.; Hershberger, Heather Nicole

2010-01-01

154

Solar Data in the Classroom: the TLRBSE Experience  

NASA Astrophysics Data System (ADS)

The Teacher Leaders in Research Based Astronomy program, based at the National Optical Astronomy Observatory in Tucson, has created an immersive research experience for middle and high school teachers at the National Solar Observatory at Sacramento Peak, New Mexico and provides support for teachers to use real solar data in the classroom. Teachers explored two months of daily multispectral images of the Sun during solar maximum using hard copy images and computer-based image processing tools and data CD-ROMs. These data sets included white light intensity, magnetograms, H-alpha, extreme ultraviolet, and x-ray images that students can explore as introductions to solar activity and to features such as sunspots, prominences, and faculae. The data can be used to trace the evolution of solar phenomena, track solar differential rotation, or to calculate daily sunspot numbers that can be compared with professional counts. Teachers also constructed and aligned low cost solar telescopes that will be used to gather data on sunspots and other white light solar phenomena. This experience with solar data and images provides a direct lead-in to additional professional data sets available online at solar observatory sites. These data can be used to detail the development of energetic events such as coronal mass ejections and to follow solar phenomena over long time periods. Of greatest relevance to the teachers were the solar data that can be correlated with space weather data and regional terrestrial data on magnetic storms, satellite failures, and power outages.

Pompea, S. M.; Walker, C. E.; Croft, S. K.; McCarthy, D. W.

2002-12-01

155

Upconverter solar cells: materials and applications  

Microsoft Academic Search

Spectral conversion of sunlight is a promising route to reduce spectral mismatch losses that are responsible for the major part of the efficiency losses in solar cells. Both upconversion and downconversion materials are presently explored. In an upconversion process, photons with an energy lower than the band gap of the solar cell are converted to higher energy photons. These higher

J. de Wild; A. Meijerink; J. K. Rath; W. G. J. H. M. van Sark; R. E. I. Schropp

2011-01-01

156

Calibration of Solar Cells in Terrestrial Sunlight.  

National Technical Information Service (NTIS)

A method of calibrating solar cells in sunlight is described. This method has been used for at least 15 years, and produces a value of the solar cell's short circuit current for any predetermined space of terrestrial condition. The main advantage of this ...

M. A. H. Davies C. Goodbody

1991-01-01

157

Solar cell parameter extraction using genetic algorithms  

Microsoft Academic Search

In this paper, a technique based on genetic algorithms is proposed for improving the accuracy of solar cell parameters extracted using conventional techniques. The approach is based on formulating the parameter extraction as a search and optimization problem. Current-voltage data used were generated by simulating a two-diode solar cell model of specified parameters. The genetic algorithm search range that simulates

Joseph A. Jervase; Hadj Bourdoucen; Ali Al-Lawati

2001-01-01

158

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

159

Si concentrator solar cell development. [Final report  

SciTech Connect

This is the final report of a program to develop a commercial, high-efficiency, low-cost concentrator solar cell compatible with Spectrolab`s existing manufacturing infrastructure for space solar cells. The period covered is between 1991 and 1993. The program was funded through Sandia National Laboratories through the DOE concentrator initiative and, was also cost shared by Spectrolab. As a result of this program, Spectrolab implemented solar cells achieving an efficiency of over 19% at 200 to 300X concentration. The cells are compatible with DOE guidelines for a cell price necessary to achieve a cost of electricity of 12 cents a kilowatthour.

Krut, D.D. [Spectrolab, Inc., Sylmar, CA (United States)

1994-10-01

160

US Polycrystalline Thin Film Solar Cells Program.  

National Technical Information Service (NTIS)

The Polycrystalline Thin Film Solar Cells Program, part of the United States National Photovoltaic Program, performs R and D on copper indium diselenide and cadmium telluride thin films. The objective of the Program is to support research to develop cells...

H. S. Ullal K. Zweibel R. L. Mitchell

1989-01-01

161

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

162

Institutional barriers to solar energy: early HUD demonstration experiences  

SciTech Connect

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 widespread. The HUD program will continue to study institutional problems for the program's passive solar grants and will focus on areas like the cities, where institutional concerns are more complex.

Mara, G.; Engel, D.

1980-03-01

163

Multiple quantum well top cells for multijunction concentrator solar cells  

Microsoft Academic Search

High efficiency quantum well GaAs solar cells have been successfully applied in commercial multijunction concentrator cells to increase the absorption in the infrared and provide variability of the absorption edge to optimise energy harvesting. Multiple quantum well (MQW) top cells can further improve the performance of multijunction solar cells since the absorption edge of top and middle subcells can be

Kan-Hua Lee; Keith W. J. Barnham; Benjamin C. Browne; James P. Connolly; Jessica G. J. Adams; Rob J. Airey; Nicholas J. Ekins-Daukes; Markus Fuhrer; Victoria Rees; Mathew Lumb; Alison L. Dobbin; Massimo Mazzer; John S. Roberts; Thomas N. D. Tibbits

2011-01-01

164

Monolithic Cascade-Type Solar Cells.  

National Technical Information Service (NTIS)

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...

S. Yamamoto A. Shibukawa M. Yamaguchi

1985-01-01

165

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

166

Performance study of solar cell arrays based on a Trough Concentrating Photovoltaic\\/Thermal system  

Microsoft Academic Search

The performances of solar cell arrays based on a Trough Concentrating Photovoltaic\\/Thermal (TCPV\\/T) system have been studied via both experiment and theoretical calculation. The I–V characteristics of the solar cell arrays and the output performances of the TCPV\\/T system demonstrated that among the investigated four types of solar cell arrays, the triple junction GaAs cells possessed good performance characteristics and

Ming Li; Xu Ji; Guoliang Li; Shengxian Wei; YingFeng Li; Feng Shi

2011-01-01

167

Producing hydrogen with a bacteriorhodopsin solar energy cell. Final technical report  

SciTech Connect

Bacteriorhodopsin-based solar cells have the following potential advantages over liquid-junction cells: Bacteriorhodopsin is very resistant chemically and is also resistant to high photon fluxes. Even though the efficiency of the experimental solar cell is still low, the theoretical efficiency, as determined from experiments is high (about 60%). The device would use inexpensive materials that are not limited in supply. The absorption properties of bacteriorhodopsin can be easily manipulated chemically or genetically to improve its characteristics in a solar cell.

Lewis, A.

1984-01-03

168

Porphyrin-sensitized solar cells.  

PubMed

Nature has chosen chlorophylls in plants as antennae to harvest light for the conversion of solar energy in complicated photosynthetic processes. Inspired by natural photosynthesis, scientists utilized artificial chlorophylls - the porphyrins - as efficient centres to harvest light for solar cells sensitized with a porphyrin (PSSC). After the first example appeared in 1993 of a porphyrin of type copper chlorophyll as a photosensitizer for PSSC that achieved a power conversion efficiency of 2.6%, no significant advance of PSSC was reported until 2005; beta-linked zinc porphyrins were then reported to show promising device performances with a benchmark efficiency of 7.1% reported in 2007. Meso-linked zinc porphyrin sensitizers in the first series with a push-pull framework appeared in 2009; the best cell performed comparably to that of a N3-based device, and a benchmark 11% was reported for a porphyrin sensitizer of this type in 2010. With a structural design involving long alkoxyl chains to envelop the porphyrin core to suppress the dye aggregation for a push-pull zinc porphyrin, the PSSC achieved a record 12.3% in 2011 with co-sensitization of an organic dye and a cobalt-based electrolyte. The best PSSC system exhibited a panchromatic feature for light harvesting covering the visible spectral region to 700 nm, giving opportunities to many other porphyrins, such as fused and dimeric porphyrins, with near-infrared absorption spectral features, together with the approach of molecular co-sensitization, to enhance the device performance of PSSC. According to this historical trend for the development of prospective porphyrin sensitizers used in PSSC, we review systematically the progress of porphyrins of varied kinds, and their derivatives, applied in PSSC with a focus on reports during 2007-2012 from the point of view of molecular design correlated with photovoltaic performance. PMID:23023240

Li, Lu-Lin; Diau, Eric Wei-Guang

2012-10-01

169

A review of the homestake solar neutrino experiment  

NASA Astrophysics Data System (ADS)

The observations from the Homestake radiochemical solar neutrino experiment over the period 1970 to 1992 are given. The observations will be compared to those from the Kamiokande II experiment, the gallium experiments and solar model calculations. A discussion is given of the question of a possible variation of the solar neutrino flux in anticorrelation with the solar activity cycle. The operation of the Homestake experiment, the sensitivity to the solar neutrino spectrum, the background processes and the various tests that have been performed are given in some detail. The Homestake and Kamiokande II experiments are compared on the basis of the standard model and the flux of 8B neutrinos. There is agreement between these two experiments during the period June 1987 to April 1990 when both experiments were observing. The average 8B neutrino flux during this period was (2.2 +/- 0.2) × 106 cm-2sec-1. A non-standard solar model of Sienkiewicz, Bahcall, and Paczynski (1990) which presumes that 50% of the core of the Sun is continually mixed on a slow time scale accounts for this reduced 8B flux and the total neutrino capture rate of the chlorine and gallium experiments. See acknowledgement for associates currently working on the Homestake experiment.

Davis, Raymond

170

Development and fabrication of a solar cell junction processing system  

NASA Astrophysics Data System (ADS)

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.

1981-10-01

171

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

172

Using solar cells as microparticle detectors in low earth orbit  

NASA Astrophysics Data System (ADS)

On retrieval from low Earth orbit (LEO), the solar arrays from the European retrievable carrier (EuReCa) and one solar array wing of the Hubble Space Telescope (HST) were inspected for micrometeoroid and space debris impact damage. Seven-hundred-three and eight-hundred-fourteen impact sites respectively were analyzed in detail. Interpretation of particle parameters from this large data set can yield a useful measurement of the micrometeoroid and debris flux in LEO. Due to similar orbital parameters, this then provides a flux measurement complimentary to those measured by the timeband capture cell experiment (TiCCE) of the EuReCa spacecraft and detectors and exposed surfaces on the Long Duration Exposure Facility (LDEF). To allow comparison of data from the space retrieved solar cells to previous data, solar cell material, glass and aluminum targets were impacted for inter-calibration using the University of Kent's Light Gas Gun (LGG). An average of 20 impact sites on each target material per shot were measured. It was decided to consider only non-perforations of the 150 micron thick CMX cover glass, common to both EuReCa and HST solar cells. Trends in crater morphology of the laboratory impacts are discussed and compared to those from space impacts. The effects of impact angle and crater scaling with particle size are investigated and a conversion from appropriate solar cell crater parameters to the ballistic limit in aluminum is presented.

Shrine, Nicholas R.; Taylor, Emma A.; Yano, H.; Griffiths, Andrew D.; McDonnell, J. Anthony M.

1996-10-01

173

Characterising dye-sensitized solar cells  

NASA Astrophysics Data System (ADS)

With growing energy and environmental concerns due to fossil fuel depletion and global warming there is an increasing attention being attracted by alternative and/or renewable sources of power such as biomass, hydropower, geothermal, wind and solar energy. In today's society there is a vast and in many cases not fully appreciated dependence on electrical power for everyday life and therefore devices such as PV cells are of enormous importance. The more widely used and commercially available silicon (semiconductor) based cells currently have the greatest efficiencies, however the manufacturing of these cells is complex and costly due to the cost and difficulty of producing and processing pure silicon. One new direction being explored is the development of dye-sensitised solar cells (DSSC). The SFI Strategic Research Centre for Solar Energy Conversion is a new research cluster based in Ireland, formed with the express intention of bringing together industry and academia to produce renewable energy solutions. Our specific area of research is in biomimetic dye sensitised solar cells and their electrical properties. We are currently working to develop test equipment, and optoelectronic models describing the performance and behaviors of dye-sensitised solar cells (Grätzel Cells). In this paper we describe some of the background to our work and also some of our initial experimental results. Based on these results we intend to characterise the opto-electrical properties and bulk characteristics of simple dye-sensitised solar cells and then to proceed to test new cell compositions.

Tobin, Laura L.; O'Reilly, Thomas; Zerulla, Dominic; Sheridan, John T.

2009-08-01

174

Solar cells based on gallium antimonide  

SciTech Connect

Liquid-phase epitaxy and diffusion from the gas phase have been used to create various kinds of GaSb-based solar cell structures intended for use in cascaded solar-radiation converters. A narrow-gap (GaSb) solar cell was studied in tandem based on a combination of semiconductors GaAs-GaSb (two p-n junctions) and GaInP/GaAs-GaSb (three p-n junctions). The maximum efficiency of photovoltaic conversion in GaSb behind the wide-gap cells is {eta} = 6.5% (at sunlight concentration ratio of 275X, AM1.5D Low AOD spectrum)

Andreev, V. M.; Sorokina, S. V.; Timoshina, N. Kh.; Khvostikov, V. P., E-mail: vikhv@scell.ioffe.ru; Shvarts, M. Z. [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation)

2009-05-15

175

Present status of buried contact solar cells  

Microsoft Academic Search

Recent years have seen substantially increased performance for laboratory Silicon solar cells. The standard commercial screen-printing cell process sequence appears unable to take advantage of many of these improvements. Consequently, until recently, the efficiency of commercial cells has lagged considerably. The buried contact cell provides a commercial approach able to bridge this gap. During 1990 and 1991, the first results

M. A. Green; S. R. Wenham; J. Zhao; S. Bowden; A. M. Milne; M. Taouk; F. Zhang

1991-01-01

176

Review of Mantech program for GaAs solar cells  

NASA Astrophysics Data System (ADS)

Experience, acquired over four years, in establishing a manufacturing process for GaAs solar cells for use on spacecraft is reported. Details are given of the process selection, the build-up of equipment and material support, and the results achieved.

Iles, P. A.; Chang, Kou-I.; Pope, W.

177

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

178

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

179

Nanocomposites for organic and hybrid organic-inorganic solar cells  

Microsoft Academic Search

The importance of nanocomposites materials such as carbon nanotubes-polymers composites for the efficient realization of innovative solar cells based on organic as well hybrid organic-inorganic solar cells is more and more evident. We present a study on the realization of dye sensitized solar cells (DSSC) and sublimation deposited solar cells, considering the impact of using nanocomposite materials in the different

A. Reale; T. M. Brown; A. Di Carlo; F. Giannini; F. Brunetti; E. Leonardi; M. Lucci; M. L. Terranova; S. Orlanducci; E. Tamburri; F. Toschi; V. Sessa

2006-01-01

180

Simple Ion Implantation System for Solar Cells.  

National Technical Information Service (NTIS)

A project has been initiated to investigate simple but effective ion implantation and pulsed annealing techniques for the fabrication of high efficiency silicon solar cells. In particular, the method aims to eliminate the mass analyser and associated comp...

M. J. Kenny J. R. Bird H. G. Broe

1982-01-01

181

Advanced Silicon Space Solar Cells Using Nanotechnology  

SciTech Connect

Application of nanotechnology and advanced optical structures offer new possibilities for improved radiation tolerance in silicon solar cells. We describe the application of subwavelength diffractive structures to enhance optical absorption near the surface, and thereby improve the radiation tolerance.

Gee, J.M.; Ruby, D.S.; Zaidi, S.H.

1999-03-31

182

Screen Printed Interdigitated Back Contact Solar Cell.  

National Technical Information Service (NTIS)

Interdigitated back contact solar cells were made by screen printing dopant materials onto the back surface of a semiconductor substrate in a pair of interdigitated patterns. These dopant materials were then diffused into the substrate to form junctions h...

C. R. Baraona G. A. Mazaris A. T. Chai

1983-01-01

183

Solar Cell Efficiency Tables (Version 34)  

SciTech Connect

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 January, 2009 are reviewed.

Green, M. A.; Emery, K.; Hishikawa, Y.; Warta, W.

2009-01-01

184

Solar-cell testing and evaluation  

SciTech Connect

A two year study of the degradation effects in AlGaAs/GaAs solar cells is described. Illuminated current-voltage measurements were made during temperature and humidity cycling and time dependent degradation measurements were recorded.

Stefanakos, E.K.; Collis, W.J.

1982-04-01

185

Cascade solar cell having conductive interconnects  

DOEpatents

Direct ohmic contact between the cells in an epitaxially grown cascade solar cell is obtained by means of conductive interconnects formed through grooves etched intermittently in the upper cell. The base of the upper cell is directly connected by the conductive interconnects to the emitter of the bottom cell. The conductive interconnects preferably terminate on a ledge formed in the base of the upper cell.

Borden, Peter G. (Menlo Park, CA); Saxena, Ram R. (Saratoga, CA)

1982-10-26

186

Saudi Arabia's experience in solar energy applications  

NASA Astrophysics Data System (ADS)

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 by KACST. The objectives, management structure, and program organization of SOLEARS are outlined, and attention is focused on urban, rural/agricultural, and industrial applications as well as resource development activities and accomplishments. Solar-hydrogen projects pursued together with Germany are reviewed, and their objectives, program management, and technical plans are covered. Domestic programs dealing with photovoltaic-powered lightning and hot-water systems are summarized.

Huraib, Fahad S.

187

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

188

Towards upconversion for amorphous silicon solar cells  

Microsoft Academic Search

Upconversion of subbandgap light of thin film single junction amorphous silicon solar cells may enhance their performance in the near infrared (NIR). In this paper we report on the application of the NIR–vis upconverter ?-NaYF4:Yb3+(18%) Er3+(2%) at the back of an amorphous silicon solar cell in combination with a white back reflector and its response to infrared irradiation. Current–voltage measurements

J. de Wild; A. Meijerink; J. K. Rath; W. G. J. H. M. van Sark; R. E. I. Schropp

2010-01-01

189

Multicrystalline silicon solar cells: Gettering optimization and characterization  

NASA Astrophysics Data System (ADS)

Three multicrystalline silicon materials were used in preliminary experiments in preparation for a planned comprehensive gettering study on several industrial solar cell materials. Two processes commonly used to upgrade material quality were investigated: phosphorus gettering and aluminum-alloying. Microwave-detected photoconductance decay measurements of minority carrier lifetime and detailed analyses of full solar cells were used to determine the response to the gettering processes. Lateral nonuniformities were shown to be significant in these multicrystalline materials. Identification of the nature of the nonuniformities is important in developing an understanding of gettering effects.

Schubert, W. K.

190

Simplified solar cell material tester  

SciTech Connect

A method is described for testing quality of photovoltaic semiconductor material having a thickness of less than one minority carrier diffusion length, for use as solar cells, by determining the minority carrier diffusion length, comprising the steps of: preparing a thin slice of semiconductor material by polishing one side thereof, and preparing the other side thereof with a predetermined surface finish; coupling to both sides of the thin slice of semiconductor material with electrodes; directing lighting having a first predetermined wavelength onto the polished surface of the sice; measuring a first photovoltage developed at the electrodes while light at the first wavelength is applied to the slice; directing light having a second different predetermined wavelength onto the slice; adjusting the light intensity so that the photovoltage developed at the electrodes while light at the second wavelength is applied to the slice is substantially the same as the first photovoltage at the first wavelength; measuring a second intensity of illumination applied to the slice at the second wavelength; determining the ratio of the light intensity at one of the first and second wavelengths relative to the light intensity at the other of the first and second wavelengths; and ascertaining the minority carrier diffusion length from the ratio.

Garlick, G.F.J.

1987-04-07

191

Investigating dye-sensitised solar cells  

NASA Astrophysics Data System (ADS)

At present there is considerable global concern in relation to environmental issues and future energy supplies, for instance climate change (global warming) and the rapid depletion of fossil fuel resources. This trepidation has initiated a more critical investigation into alternative and renewable sources of power such as geothermal, biomass, hydropower, wind and solar energy. The immense dependence on electrical power in today's society has prompted the manufacturing of devices such as photovoltaic (PV) cells to help alleviate and replace current electrical demands of the power grid. The most popular and commercially available PV cells are silicon solar cells which have to date the greatest efficiencies for PV cells. The drawback however is that the manufacturing of these cells is complex and costly due to the expense and difficulty of producing and processing pure silicon. One relatively inexpensive alternative to silicon PV cells that we are currently studying are dye-sensitised solar cells (DSSC or Grätzel Cells). DSSC are biomimetic solar cells which are based on the process of photosynthesis. The SFI Strategic Research Centre for Solar Energy Conversion is a research cluster based in Ireland formed with the express intention of bringing together industry and academia to produce renewable energy solutions. Our specific research area is in DSSC and their electrical properties. We are currently developing testing equipment for arrays of DSSC and developing optoelectronic models which todescribe the performance and behaviour of DSSCs.

Tobin, Laura L.; O'Reilly, Thomas; Zerulla, Dominic; Sheridan, John T.

2010-04-01

192

Solar energy-conversion processes in organic solar cells  

NASA Astrophysics Data System (ADS)

Organic semiconducting materials have demonstrated attractive light-absorption and photocurrent-generation functions due to their delocalized ? electrons as well as intra-molecular and inter-molecular charge separation processes. On the other hand, organic semiconducting materials have easy property tuning, are mechanically flexible, and have large-area thin film formation properties. As a result, organic materials have become potential candidates in solar energy applications. This article will review critical energy-conversion processes in organic solar cells with the focus on singlet and triplet photovoltaic responses.

Xu, Zhihua; Zang, Huidong; Hu, Bin

2008-09-01

193

Monolithic solar cell panel of amorphous silicon  

Microsoft Academic Search

A monolithic solar cell panel has been fabricated using hydrogenated amorphous silicon (a-Si:H) as the semiconductor material. This device consists of a plate glass substrate bearing a number of long, narrow, parallel cells electrically connected in series along the lengths of the cells. It features several characteristics which make it uniquely attractive for large area devices (up to several sq

J. J. Hanak

1979-01-01

194

ISEE-C Solar Wind Plasma Experiment  

Microsoft Academic Search

Two 135° spherical section electrostatic analyzers furnish electron and ion measurements of the solar wind on ISEE-C. Each of these instruments utilizes a divided secondary emitter system to intercept the analyzed particles. Secondary electrons selected from all of the emitters simultaneously provide fast two-dimensional measurements of the particle fluxes integrated over polar angle; at a slower rate secondary electrons are

S. J. Bame; J. R. Asbridge; H. E. Felthauser; J. P. Glore; H. L. Hawk; J. Chavez

1978-01-01

195

High efficiency amorphous silicon germanium solar cells  

Microsoft Academic Search

We report high-efficiency single-junction a-SiGe n-i-p solar cells deposited using rf PECVD on stainless steel (SS) substrates coated with metal\\/ZnO back-reflector (BR). The initial and stabilized active-area efficiencies have been improved to 12.5-13.0% and 10.4%, respectively, for 0.25 cm2 a-SiGe cells. The achievement of single-junction cells with such high efficiencies, equivalent to those for the state-of-the-art triple-junction solar cells, are

X. Liao; W. Du; X. Yang; H. Povolny; X. Xiang; X. Deng

2005-01-01

196

Nanoparticle Solar Cell Final Technical Report  

SciTech Connect

The purpose of this work was to demonstrate all-inorganic nanoparticle-based solar cells with photovoltaic performance extending into the near-IR region of the solar spectrum as a pathway towards improving power conversion efficiencies. The field of all-inorganic nanoparticle-based solar cells is very new, with only one literature publication in the prior to our project. Very little is understood regarding how these devices function. Inorganic solar cells with IR performance have previously been fabricated using traditional methods such as physical vapor deposition and sputtering, and solution-processed devices utilizing IR-absorbing organic polymers have been investigated. The solution-based deposition of nanoparticles offers the potential of a low-cost manufacturing process combined with the ability to tune the chemical synthesis and material properties to control the device properties. This work, in collaboration with the Sue Carter research group at the University of California, Santa Cruz, has greatly expanded the knowledge base in this field, exploring multiple material systems and several key areas of device physics including temperature, bandgap and electrode device behavior dependence, material morphological behavior, and the role of buffer layers. One publication has been accepted to Solar Energy Materials and Solar Cells pending minor revision and another two papers are being written now. While device performance in the near-IR did not reach the level anticipated at the beginning of this grant, we did observe one of the highest near-IR efficiencies for a nanoparticle-based solar cell device to date. We also identified several key parameters of importance for improving both near-IR performance and nanoparticle solar cells in general, and demonstrated multiple pathways which showed promise for future commercialization with further research.

Breeze, Alison, J; Sahoo, Yudhisthira; Reddy, Damoder; Sholin, Veronica; Carter, Sue

2008-06-17

197

The small community solar thermal power experiment  

Microsoft Academic Search

Contractors were asked to develop a preferred system concept, to perform sensitivity analyses, and to outline recommended approaches for the follow-on design program of a one-megawatt solar thermal demonstration plant. The systems recommended by the contractors in each of the categories were: (1) McDonnell-Douglas Astronautics Company: Central tower with field of south-facing heliostats; (2) General Electric Company: Field of parabolic

T. Kiceniuk

1981-01-01

198

Low Cycle Fatigue (LCF) of Solar Cell Welding Joints Made of Silver.  

National Technical Information Service (NTIS)

To improve solar cell modules for low Earth orbit missions of greater than 10 yr, low cycle fatigue investigations on silver interconnectors welded on silverized silicon solar cells were conducted. Experiments on 20 and 35 micron thick Ag-foil interconnec...

S. Reul

1986-01-01

199

Thin-Film Technology in Intermediate Band Solar Cells: Advanced Concepts for Chalcopyrite Solar Cells  

NASA Astrophysics Data System (ADS)

Combining the two key factors of high performance and low cost into a single solar cell is the major challenge of research on photovoltaics. It is not easy to conceive a practical approach to such a device if not based on thin-film technology. Yet, it appears equally clear that current thin-film solar cells must upgrade their performance by some means in order to meet satisfactory energy conversion efficiencies. The incorporation of novel photovoltaic concepts, particularly the intermediate band solar cell, into thin-film technologies is expected to cross-fertilize both fields. In this chapter, we will outline the potential benefits ofthin-film intermediate band solar cells (TF-IBSC) and describe two different approaches toward its practical implementation. Particular attention will be devoted to devices based on chalcopyrite absorbers, currently leading the efficiency records of thin-film solar cells, and characterized by material properties well suited for this purpose.

Marrón, David Fuertes

200

Solar Cells for High Temperature Environments in Space  

NASA Astrophysics Data System (ADS)

Future NASA missions into regions close to the sun will require power systems to operate in high temperature, high light-intensity environments. Some of the missions are: *Solar Probe Plus *Mercury probes *Venus probes Approaches to solar array design include developing improved high-temperature solar cells, reducing incident intensity to limit temperature, and use of cooling to minimize the temperature. Each of these missions has different challenges. Solar Probe Plus, a mission to the outer corona of the sun, will operate from 1 AU inward to 9.5 solar radii from the sun, nearly three orders of magnitude in incident intensity. Probes to the surface of Mercury experience a solar intensity of 10 kW/m^2 with temperature ranging from 425^oC at noon to -175^oC at night; while Mercury orbital missions are subject to incident solar radiation, reflected sunlight, and thermal IR radiated from the planet's surface. Venus presents the greatest challenge to photovoltaic operation, with surface temperature of 450^oC, low intensity sunlight, and a corrosive environment.

Landis, Geoffrey

2010-04-01

201

Glass-Si Heterojunction Solar Cells.  

National Technical Information Service (NTIS)

Measurements on SnO2/n-Si heterojunction solar cells indicate the electron affinity of SnO2 about 0.85 eV greater than of Si. The principal dark current mechanism is electron emission; the operation is evidently similar to Schottky barrier cells. Rapid de...

R. L. Anderson G. Kent

1975-01-01

202

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

203

Thin-Film Amorphorus Silicon Solar Cells.  

National Technical Information Service (NTIS)

The research programme on amorphous silicon solar cells with the structure Ni/TiOx/undoped amorphous silicon/'n+' amorphous silicon/stainless steel, was divided into three phases, the target being an 8% efficient 1 cm2 cell. It dealt with the growth of am...

R. J. Holwill J. McGill F. Riddoch P. Robinson S. D. Smith

1982-01-01

204

Automatic laser scanner for solar cells  

SciTech Connect

An instrument is described which controls a two-mirror scanning arrangement to raster a laser beam on a large-area solar cell. The short circuit current thus produced is plotted on an X--Y recorder, or recorded on a storage oscilloscope to study the spatial inhomogeneities of the cell.

Khanna, V.; Sastry, O.S.; Mukerjee, A.K.; Chopra, K.L.

1984-10-01

205

Thin Film Solar Cells for Terrestrial Applications.  

National Technical Information Service (NTIS)

The goals of the project are to develop a terrestrial version of the CdS thin film solar cell that is demonstrably amenable to low cost mass production, and to establish data on the lifetime of such cells under the expected conditions of terrestrial use. ...

F. A. Shirland W. J. Biter E. W. Greeneigh T. P. Brody

1975-01-01

206

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

207

Scanning Probe Microscopy of Organic Solar Cells  

NASA Astrophysics Data System (ADS)

Nanostructured composites of organic semiconductors are a promising class of materials for the manufacture of low-cost solar cells. Understanding how the nanoscale morphology of these materials affects their efficiency as solar energy harvesters is crucial to their eventual potential for large-scale deployment for primary power generation. In this thesis we describe the use of optoelectronic scanning-probe based microscopy methods to study this efficiency-structure relationship with nanoscale resolution. In particular, our objective is to make spatially resolved measurements of each step in the power conversion process from photons to an electric current, including charge generation, transport, and recombination processes, and correlate them with local device structure. We have achieved two aims in this work: first, to develop and apply novel electrically sensitive scanning probe microscopy experiments to study the optoelectronic materials and processes discussed above; and second, to deepen our understanding of the physics underpinning our experimental techniques. In the first case, we have applied conductive-, and photoconductive atomic force (cAFM & pcAFM) microscopy to measure both local photocurrent collection and dark charge transport properties in a variety of model and novel organic solar cell composites, including polymer/fullerene blends, and polymer-nanowire/fullerene blends, finding that local heterogeneity is the rule, and that improvements in the uniformity of specific beneficial nanostructures could lead to large increases in efficiency. We have used scanning Kelvin probe microscopy (SKPM) and time resolved-electrostatic force microscopy (trEFM) to characterize all-polymer blends, quantifying their sensitivity to photochemical degradation and the subsequent formation of local charge traps. We find that while trEFM provides a sensitive measure of local quantum efficiency, SKPM is generally unsuited to measurements of efficiency, less sensitive than trEFM, and of greater utility in identifying local changes in steady-state charge density that can be associated with charge trapping. In the second case, we have developed a new understanding of charge transport between a sharp AFM tip and planar substrates applicable to conductive and photoconductive atomic force microscopy, and shown that hole-only transport characteristics can be easily obtained including quantitative values of the charge carrier mobility. Finally, we have shown that intensity-dependent photoconductive atomic force microscopy measurements can be used to infer the 3D structure of organic photovoltaic materials, and gained new insight into the influence vertical composition of the these devices can have on their open-circuit voltage and its intensity dependence.

Reid, Obadiah G.

208

Surface plasmon enhanced silicon solar cells  

NASA Astrophysics Data System (ADS)

Thin-film solar cells have the potential to significantly decrease the cost of photovoltaics. Light trapping is particularly critical in such thin-film crystalline silicon solar cells in order to increase light absorption and hence cell efficiency. In this article we investigate the suitability of localized surface plasmons on silver nanoparticles for enhancing the absorbance of silicon solar cells. We find that surface plasmons can increase the spectral response of thin-film cells over almost the entire solar spectrum. At wavelengths close to the band gap of Si we observe a significant enhancement of the absorption for both thin-film and wafer-based structures. We report a sevenfold enhancement for wafer-based cells at ?=1200 nm and up to 16-fold enhancement at ?=1050 nm for 1.25 ?m thin silicon-on-insulator (SOI) cells, and compare the results with a theoretical dipole-waveguide model. We also report a close to 12-fold enhancement in the electroluminescence from ultrathin SOI light-emitting diodes and investigate the effect of varying the particle size on that enhancement.

Pillai, S.; Catchpole, K. R.; Trupke, T.; Green, M. A.

2007-05-01

209

Towards highly efficient solar cells  

NASA Astrophysics Data System (ADS)

Suntech Power is the world's largest producer of solar panels and has delivered more than 20 million photovoltaic panels to more than 80 countries around the globe. Nature Photonics spoke with Stuart Wenham, chief technology officer at Suntech Power, to find out more about its activities and visions.

2012-03-01

210

Nanocrystal-polymer solar cells  

Microsoft Academic Search

The ability to structure materials on a nanometer dimension enables the processes of solar energy conversion to be optimized at their most fundamental length scale. In semiconducting nanocrystals, optical absorption and electrical transport can be tailored by changing their radius and length, respectively. The unique features of quantum confinement and shape manipulation characteristic for inorganic nanocrystals can be utilized to

Wendy Uyen Huynh

2002-01-01

211

Fill factor in organic solar cells.  

PubMed

The fill factor (FF) is an important parameter that determines the power conversion efficiency of an organic solar cell. There are several factors that can significantly influence FF, and these factors interact with each other very intricately. Due to this reason, a deep understanding of FF is quite difficult. Based on the three fundamental elements in the solar cell equivalent circuit, namely series resistance, shunt resistance and diode, we reviews the research progress in understanding on FF in organic solar cells. Physics lying behind the often-observed undesirable S-shaped J-V curves is also summarized. This paper aims to give a brief and comprehensive summary on FF from a fundamental point of view. PMID:23652780

Qi, Boyuan; Wang, Jizheng

2013-05-07

212

Solar cell parameter extraction using genetic algorithms  

NASA Astrophysics Data System (ADS)

In this paper, a technique based on genetic algorithms is proposed for improving the accuracy of solar cell parameters extracted using conventional techniques. The approach is based on formulating the parameter extraction as a search and optimization problem. Current-voltage data used were generated by simulating a two-diode solar cell model of specified parameters. The genetic algorithm search range that simulates the error in the extracted parameters was varied from ±5 to ±100% of the specified parameter values. Results obtained show that for a simulated error of ±5% in the solar cell model values, the deviation of the extracted parameters varied from 0.1 to 1% of the specified values. Even with a simulated error of as high as ±100%, the resulting deviation only varied from 2 to 36%. The performance of this technique is also shown to surpass the quasi-Newton method, a calculus-based search and optimization algorithm.

Jervase, Joseph A.; Bourdoucen, Hadj; Al-Lawati, Ali

2001-11-01

213

The characteristics of solar cells exposed to ?-radiation  

Microsoft Academic Search

We have investigated the characteristics of solar cells exposed to ?-radiation from the standpoint of developing such gamma cells utilizing nuclear spent fuels. The examination was performed for three representative types of solar cells, i.e. amorphous, monocrystalline and polycrystalline types. These solar cells were remotely irradiated using a highly intensive 60Co ?-source instead of spent fuels, and the induced current

Norikazu Horiuchi; Koichi Taniguchi; Masaki Kamiki; Takashi Kondo; Masanori Aritomi

1997-01-01

214

The small community solar thermal power experiment  

NASA Astrophysics Data System (ADS)

Contractors were asked to develop a preferred system concept, to perform sensitivity analyses, and to outline recommended approaches for the follow-on design program of a one-megawatt solar thermal demonstration plant. The systems recommended by the contractors in each of the categories were: (1) McDonnell-Douglas Astronautics Company: Central tower with field of south-facing heliostats; (2) General Electric Company: Field of parabolic dishes with steam piped to a central turbine-generator unit; and (3) Ford Aerospace and Communications Corporation: Field of parabolic dishes with a Stirling cycle engine/generator unit at the focus of each dish. A description of each of the proposed experimental plants is given.

Kiceniuk, T.

1981-05-01

215

Multichromophore light harvesting in hybrid solar cells.  

PubMed

A new technologically relevant method for multichromophore sensitizing of hybrid blend solar cells is presented. Two dyes having complementary absorption in the UV-visible regions are individually adsorbed on nanocrystalline TiO(2) powder. These dyed TiO(2) nanoparticles are blended with an organic hole-conductor (HC) Spiro-OMeTAD in desired compositions and applied on a conducting substrate by doctor-blading at room temperature to fabricate multichromophore-sensitized hybrid blend solar cells. The external quantum efficiency (EQE) of the single hybrid layer system fabricated with two dyes, that absorb mainly UV (TPD dye) and visible regions (Ru-TPA-NCS dye), exhibited a clear panchromatic response with the sum of the EQE characteristics of each single dye cell. The first results of a multichromophore-sensitized solid-state solar cell showed J(sc) of 2.1 mA cm(-2), V(oc) of 645 mV, FF of 47% and efficiency of 0.65% at AM 1.5 G, 100 mW cm(-2) illumination intensity. The J(sc) of the multichromophore cell is the sum of the individually dyed solar cells. The process described here is technically very innovative and very simple in procedure. It has potentials to be adopted for panchromatic sensitization using more than two dyes in a single hybrid layer or layer-wise fabrication of a tandem structure at room temperature. PMID:21695348

Bandara, Jayasundera; Willinger, Katja; Thelakkat, Mukundan

2011-06-22

216

Gallium arsenide solar cell radiation damage study  

SciTech Connect

An analysis has been made of electrons and proton damaged GaAs solar cells suitable for use in space. The authors find that although some electrical parametric data and spectral response data are quite similar, the type of damage due to the two types of radiation is different. An I {minus} V analysis model shows that electrons damage the bulk of the cell and its currents relatively more while protons damage the junction of the cell and its voltages more.

Maurer, R.H.; Herbert, G.A.; Kinnison, J.D. (The Johns Hopkins Univ., Applied Physics Lab., Laurel, MD (US)); Meulenberg, A. (COMSAT Lab., Clarksburg, MD (US))

1989-12-01

217

CRLS-229 solar X-ray spectrometer/spectroheliograph experiment  

NASA Astrophysics Data System (ADS)

The CRLS-229 Solar X-ray Spectrometer/Spectroheliograph was launched in the solar pointed section of the United States Air Force Space Test Program P78-1 satellite on 24 February 1979. The SOLEX collimated Bragg crystal spectrometer experiment and the MONEX solar X-ray monitor experiment were built by The Aerospace Corporation, and the Naval Research Laboratory supplied the SOLFLEX uncollimated solar flare crystal spectrometer and the MAGMAP magnesium mapping experiment. The SOLEX A spectrometer has a 20 arc sec multigrid collimator, an ADP or RAP crystal, and proportional counter detector with a 25 micrometers thick beryllium window. The SOLEX B spectrometer has a 60 arc sec collimator, an ADP or RAP crystal, and a channel electron multiplier array detector. The SOLEX crystals and detectors can be driven so that either spectrometer exposes RAP to the collimated solar X-rays while the other exposes ADP. The spacecraft pointing system can raster the SOLEX collimator over the whole sum or a 5 x 5 arc minute region to build up a monochromatic image, or it can point the instrument anywhere on the sun so that spectra in the 3-25 angstroms range are obtained.

Landecker, P. B.; Chater, W. T.; Howey, C. K.; McKenzie, D. L.; Rugge, H. R.

1979-10-01

218

Electroluminescence from CdTe Solar Cells  

NASA Astrophysics Data System (ADS)

We have observed room-temperature electroluminescence (EL) from CdTe/CdS thin film solar cells. The spectral shape of the emission is similar to photoluminescence from the CdTe/CdS junction of the same devices. We attribute the electroluminescence to recombination of injected electrons and holes at the CdTe/CdS interface. The integrated electroluminescence intensity shows super-quadratic dependence on the device current. The EL intensity is shown to decrease after one-sun light soaking. These results demonstrate electroluminescence to be a promising characterization tool for CdTe/CdS solar cells. This work supported by the National Renewable Energy Laboratory (NREL).

Price, K. J.; Vasko, A.; Compaan, A. D.

2002-03-01

219

Analysis of space environment damage to solar cell assemblies from LDEF experiment A0171-GSFC test plate. Final report, 21 July 1993-19 August 1994  

Microsoft Academic Search

The space environment in earth orbit has been extensively studied and documented. The most serious factors influencing electrical systems (including solar arrays) are the local radiation environment, thermal cycling effects, local plasma density, neutral particle density, spacecraft surfaces outgassing\\/effuent products, and the meteroid and debris flux. The radiation environment (proton, electron, and photon), fueled primarily by the sun but also

D. C. Hill; M. F. Rose

1994-01-01

220

Optimum operating conditions of a solar cell panel and prediction of solar radiation in Sanaa, Yemen  

Microsoft Academic Search

Results of a study of the performance of solar cells under nominal operating conditions in Yemen are reported. The solar cell panel comprised 14 Si cells of .003 sq m surface area each, and was mounted on a rooftop with the solar radiation being measured by a pyranometer. Further monitoring was performed of the panel surface temperature, the ambient air

A. Khogali; M. R. I. Ramadan

1982-01-01

221

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

222

Process development for high-efficiency silicon solar cells.  

National Technical Information Service (NTIS)

Fabrication of high-efficiency silicon solar cells in an industrial environment requires a different optimization than in a laboratory environment. Strategies are presented for process development of high-efficiency silicon solar cells, with a goal of sim...

J. M. Gee P. A. Basore M. E. Buck D. S. Ruby W. K. Schubert

1991-01-01

223

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

224

Plastic solar cells with engineered interfaces  

NASA Astrophysics Data System (ADS)

We discuss here bulk-heterojunction polymer solar cells with engineered interfaces to achieve desired phase separations (vertical and horizontal), molecule orientations, ohmic contacts, and electronic properties for device performance maximization, and to enhance the device durability by eliminating corrosive interfacial layers. The strategies discussed include development of novel interfacial layers such as self-assembled organic layers and inorganic metal oxide layers, and using inverted cell architectures. Interface engineering leads to optimal active layer morphologies and to polymer ?- orientation, as well as maximum open circuit voltage. Using p-type NiO as the anode hole transporting/electron blocking layer results in dramatically enhanced device performance of P3HT/PCBM polymer solar cells with PCEs up to 5%. Electrical property and surface morphology investigations of NiO elucidate the mechanism for the enhanced performance. Other novel interfacial materials such as self-assembled organic monolayers and graphene oxide (GO) have also been incorporated into polymer solar cells to achieve comparable PCEs with improved device stability. Using ZnO as electron transporting/hole blocking layer and employing an inverted device architecture, polymer solar cells achieve desired molecule ?-orientation and vertical phase separation, therefore extremely high fill factors and promising power conversion efficiencies. In addition to interfacial layer materials, active layer components with state-of-the-art device performance, both polymer and small molecule developed in this laboratory, will also be discussed.

Guo, Xugang; Marks, Tobin J.

2013-03-01

225

Multi-junction solar cell device  

DOEpatents

A multi-junction solar cell device (10) is provided. The multi-junction solar cell device (10) comprises either two or three active solar cells connected in series in a monolithic structure. The multi-junction device (10) comprises a bottom active cell (20) having a single-crystal silicon substrate base and an emitter layer (23). The multi-junction device (10) further comprises one or two subsequent active cells each having a base layer (32) and an emitter layer (23) with interconnecting tunnel junctions between each active cell. At least one layer that forms each of the top and middle active cells is composed of a single-crystal III-V semiconductor alloy that is substantially lattice-matched to the silicon substrate (22). The polarity of the active p-n junction cells is either p-on-n or n-on-p. The present invention further includes a method for substantially lattice matching single-crystal III-V semiconductor layers with the silicon substrate (22) by including boron and/or nitrogen in the chemical structure of these layers.

Friedman, Daniel J. (Lakewood, CO); Geisz, John F. (Wheat Ridge, CO)

2007-12-18

226

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

227

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

228

Advanced solar receivers high temperature steam loop experiments  

Microsoft Academic Search

A high temperature steam loop experiment was built to examine the critical design problems associated with a solar cavity receiver\\/steam generator combination with central receiver application. The test loop consists of a once through monotube steam generator mounted in a downward facing cavity receiver with external circulation and condensing systems. The thermal input to the receiver with external circulation and

A. H. Campbell; H. L. Teague

1980-01-01

229

Solar Energy: Lessons from the Pacific Island Experience.  

National Technical Information Service (NTIS)

The report on the experiences of several Pacific island countries provides a clear indication that in small, remote villages, off-the-shelf solar photovoltaic (PV) technologies are providing reliable power at costs less than those of the more commonly use...

A. Liebenthal S. Mathur H. Wade

1994-01-01

230

Skylab Experiments, Volume I, Physical Science, Solar Astronomy.  

ERIC Educational Resources Information Center

Up-to-date knowledge about Skylab experiments is presented for the purpose of informing high school teachers about scientific research performed in orbit and enabling them to broaden their scope of material selection. The first volume is concerned with the solar astronomy program. The related fields are physics, electronics, biology, chemistry,…

National Aeronautics and Space Administration, Washington, DC.

231

Skylab Experiments, Volume I, Physical Science, Solar Astronomy.  

ERIC Educational Resources Information Center

|Up-to-date knowledge about Skylab experiments is presented for the purpose of informing high school teachers about scientific research performed in orbit and enabling them to broaden their scope of material selection. The first volume is concerned with the solar astronomy program. The related fields are physics, electronics, biology, chemistry,…

National Aeronautics and Space Administration, Washington, DC.

232

Basic experiments related to the advanced solar pond (ASP) performance  

Microsoft Academic Search

This paper concerns an experimental evaluation of the basic aspects of operation of the advanced solar pond (ASP). Experiments wee carried out in a laboratory test section in order to assess the feasibility of the density gradient maintenance in stratified flowing layers. The density stratification was caused by a non uniform distribution of temperatures in the flow field. Results of

Y. Keren; G. A. Bemporad; H. Rubin

1991-01-01

233

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

234

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

235

Alternative method for the performance analysis of silicon solar cells  

SciTech Connect

An approximate formula for electron-hole generation rate has been proposed. The proposed approximation is found to give good representation of the actual generation rate provided by Dunbar and Hauser and by Fossum. In order to determine the applicability of this approximation attempts have been made to calculate short-circuit current, open-circuit voltage, and solar cell efficiency of an n/sup +/p silicon solar cell. The calculations involve consideration of nonuniform doping, spatial dependence of the band, and drift field for the n/sup +/ region, and band gap narrowing, Shockley--Read--Hall recombination, and Auger recombination for both n/sup +/ and p regions. The variations of short-circuit current, open-circuit voltage, and solar cell efficiency with doping concentration of the substrate p region are found to be in good agreement with results obtained from experiments. The trend of the results indicates that proper optimization of the width and impurity concentration of the diffused n region, of the width and impurity concentration of the substrate p region, and of the front-surface recombination velocity is necessary for achieving the highest efficiency of a solar cell.

Mohammad, S.N.

1987-01-15

236

Experimenting with concentrated sunlight using the DLR solar furnace  

SciTech Connect

The high flux solar furnace that is operated by the Deutsche Forschungsanstalt fuer Luft- und Raumfahrt (DLR) at Cologne was inaugurated in June 1994 and we are now able to look back onto one year of successful operation. The solar furnace project was founded by the government of the State Northrhine Westfalia within the Study Group AG Solar. The optical design is a two-stage off-axis configuration which uses a flat 52 m{sup 2} heliostat and a concentrator composed of 147 spherical mirror facets. The heliostat redirects the solar light onto the concentrator which focuses the beam out of the optical axis of the system into the laboratory building. At high insolation levels (>800W/m{sup 2}) it is possible to collect a total power of 20 kW with peak flux densities of 4 MW/m{sup 2}. Sixteen different experiment campaigns were carried out during this first year of operation. The main research fields for these experiments were material science, component development and solar chemistry. The furnace also has its own research program leading to develop sophisticated measurement techniques like remote infrared temperature sensing and flux mapping. Another future goal to be realized within the next five years is the improvement of the performance of the furnace itself. 6 refs., 9 figs., 1 tab.

Neumann, A.; Groer, U. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt Linder Hoehe, Koeln (Germany)

1996-10-01

237

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

238

Material constraints for thin-film solar cells  

Microsoft Academic Search

Harnessing solar energy by using photovoltaic cells has the potential to become a major CO2-free energy source. Materials requirements for the solar cells based on four types of thin-film photovoltaics have been estimated and compared with global reserves, resources and annual refining. The use of solar cells based on Cd, Ga, Ge, In, Ru, Se and Te as a major

B. A Andersson; C Azar; J Holmberg; S Karlsson

1998-01-01

239

Determination of the solar cell panel installation angle  

Microsoft Academic Search

The output power of the solar cell panel is highly affected by the sunlight incident angle. The efficiency can be improved if the solar cell panel is properly installed with the optimum angle. The relationship between the sunlight incident angle and the sunlight radiation intensity on the solar cell panel surface is presented in this paper. Genetic algorithms with climatic

Yaow-Ming Chen; Hsu-Chin Wu

2001-01-01

240

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

241

Photon degradation effects in terrestrial solar cells  

Microsoft Academic Search

A certain type of photon degradation effect has been observed experimentally in n(+)\\/p solar cells. It is found that this effect is caused by a recombination center, the formation of which requires the simultaneous presence of a lattice defect and a silver atom or complex of atoms. The center is electrically active in its equilibrium state; the energy level of

V. G. Weizer; H. W. Brandhorst; J. D. Broder; R. E. Hart; J. H. Lamneck

1978-01-01

242

Screen printed boron emitters for solar cells  

Microsoft Academic Search

Screen printed (SP) boron emitters are presented as a useful option for the manufacturing of p-type emitters of solar cells. Details are provided on the diffusion process, including deposition, drying and firing steps, the latter performed in an infrared belt furnace. Besides their main dependences on the firing conditions, the sheet resistances and dopant profiles of the resulting emitters reveal

F. Recart; I. Freire; L. Pérez; R. Lago-Aurrekoetxea; J. C. Jimeno; G. Bueno

2007-01-01

243

The fatigue properties of solar cell interconnectors  

Microsoft Academic Search

The fatigue properties of varieties of silver plated molybdenum and silver mesh solar cell interconnectors were determined by deflection controlled cyclic tests at low temperature using a specially designed test unit. While the test conditions did not exactly simulate those experienced in service, the results allow comparisons to be made based on the fatigue properties of existing interconnectors and conclusions

R. B. Evans; S. Stevens

1978-01-01

244

Fatigue properties of solar cell interconnectors  

Microsoft Academic Search

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 a closed loop system of control. The molybdenum interconnectors contain a complex loop to provide flexibility. The effect

R. B. Evans; S. Stevens; P. Campbell

1977-01-01

245

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

246

A Bicontinuous Double Gyroid Hybrid Solar Cell  

Microsoft Academic Search

We report the first successful application of an ordered bicontinuous gyroid semiconducting network in a hybrid bulk heterojunction solar cell. The freestanding gyroid network is fabricated by electrochemical deposition into the 10 nm wide voided channels of a self-assembled, selectively degradable block copolymer film. The highly ordered pore structure is ideal for uniform infiltration of an organic hole transporting material,

Edward J. W. Crossland; Marleen Kamperman; Mihaela Nedelcu; Caterina Ducati; Ulrich Wiesner; Detlef-M. Smilgies; Gilman E. S. Toombes; Marc A. Hillmyer; Sabine Ludwigs; Ullrich Steiner; Henry J. Snaith

2009-01-01

247

Integral screen printed solar cells panel  

Microsoft Academic Search

This paper summarizes our activities in the field of process technologies for the fabrication of photovoltaic devices. The study is strongly focused on the integral screen printing technique for the fabrication of single crystal solar cells, using standard equipments available in our laboratory. The challenging aim of this survey is to attain encouraging results with very modest means. Knowing that

Y. Boukennous; B. Benyahia; M. R. Charif; A. Elamrani; M. F. Moussa

248

Phthalocyanine Blends Improve Bulk Heterojunction Solar Cells  

PubMed Central

A core phthalocyanine platform allows engineering the solubility properties the band gap; shifting the maximum absorption toward the red. A simple method to increase the efficiency of heterojunction solar cells uses a self-organized blend of the phthalocyanine chromophores fabricated by solution processing.

Varotto, Alessandro; Nam, Chang-Yong; Radivojevic, Ivana; Tome, Joao; Cavaleiro, Jose A.S.; Black, Charles T.; Drain, Charles Michael

2010-01-01

249

Development of high efficiency solar cells  

Microsoft Academic Search

Emphasis was on developing new polycrystal growth techniques, developing new analytical techniques to study grain boundaries, and fundamental studies of the physical mechanisms by which grain boundaries limit solar cell performance. Molecular beam epitaxy proved to be a very attractive technique for fundamental studies of both grain boundaries and unique device structures. Several high spatial resolution analytical techniques were developed

D. L. Miller; M. J. Cohen; J. S. Harris Jr.; J. J. Loferski; J. Ballantyne; T. Bhar; E. Stefanakos

1979-01-01

250

Solar-Cell Testing and Evaluation.  

National Technical Information Service (NTIS)

A two year study of the degradation effects in AlGaAs/GaAs solar cells is described. Illuminated current-voltage measurements were made during temperature and humidity cycling and time dependent degradation measurements were recorded. (ERA citation 07:061...

E. K. Stefanakos W. J. Collis

1982-01-01

251

Screen printed interdigitated back contact solar cell  

NASA Astrophysics Data System (ADS)

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.

1984-10-01

252

Microscopy for Graetzel Solar cells manufacturing  

Microsoft Academic Search

The Graetzel solar cells are devices composed by two transparent glass conductive surfaces, one nanocrystalline structure interfase of TiO 2 , where a dye is introduced. The manufacturing process includes tasks where microscopy is an important tool. For instance an intermediate task is make conductive a SiO2 glass that normally is non conductive, so it is necessary take into account

Héctor I. Olmos Castillo; Gerardo Zavala Guzmán

253

Transparent conductors for solar cell applications  

SciTech Connect

Non-stoichiometric and doped films of oxides of Sn, In, Cd, Zn and their alloys are highly transparent in the visible and also electrically conducting. The preparation and electro-optical properties of these films, and their applications in solar cells are reviewed.

Chopra, K.L.; Major, S.

1983-05-01

254

Defect analysis in polycrystalline silicon solar cells  

SciTech Connect

Localized bulk defects like diffusion length variations and structural defects like grain boundaries are analyzed in polycrystalline silicon solar cells using laser scanning and deep level transient spectroscopy techniques. The effect of hydrogen passivation on the role of grain boundaries has been studied.

Sastry, O.S.; Dutta, V.; Mukerjee, A.K.; Chopra, K.L.

1985-06-15

255

Nanostructured Solar Cells for High Efficiency Photovoltaics  

Microsoft Academic Search

The use of nanostructures in photovoltaics offers the potential for high efficiency by either using new physical mechanisms or by allowing solar cells which have efficiencies closer to their theoretical maximum, for example by tailoring material properties. At the same time, nanostructures have potentially low fabrication costs, moving to structures or materials which can be fabricated using chemically or biologically

Christiana B. Honsberg; Allen M. Barnett; Douglas Kirkpatrick

2006-01-01

256

Improved Thin-Film Solar Cells.  

National Technical Information Service (NTIS)

During this contract thin-film GaAs solar cells using semitransparent Pt layers as the barrier contact have been made and investigated to improve their photovoltaic characteristics. Studies of the GaAs film, grown by the close-spaced oxide transport proce...

D. M. Perkins W. L. Hui G. Noel E. F. Pasierb

1966-01-01

257

Indium Phosphide Solar Cells: a Materials Growth Study.  

NASA Astrophysics Data System (ADS)

The objective of this research was the fabrication and optimization of InP material to improve solar cells for space applications. The performance of solar cells is determined to a large extent by the quality of the material used to fabricate these structures. For the n ^+pp^+ cells used here, the important material properties are: lifetime in the p-type base, and dopant incorporation and heavy doping effects in the n^+ emitter. In this thesis, study of these properties and growth processes is reported. To maximize hole lifetime in undoped InP, it was studied as a function of growth conditions. The lifetime increases proportional to the growth rate, and is approximately 50 ns for a growth rate of 4.5 mum/hr. A series of experiments showed that the non-radiatively controlled lifetime is limited by impurities coming from the phosphine. This work suggests that, to get higher lifetime, an improved source of phosphine is required. The complete solar cell utilizes doped regions and its fabrication requires a series of thermal processes. The lifetime in this structure could be reduced either due to the dopant or the thermal processing. The electron lifetime was measured for solar cells with a Cd doped base, and was approximately 5 ns. The results indicate that Cd is an excellent acceptor for solar cells as it does not affect lifetime, and that the processing steps have little effect on the material. For the n^+ emitter, a study of the incorporation behaviour of S for heavy doping levels is reported. Regimes of linear, superlinear, and retrograde incorporations are observed. An incorporation model is presented to explain this behaviour. Heavy doping of semiconductor distorts the band structure and reduces the band gap. Room temperature photoluminescence is used to quantify these heavy doping effects for S doped InP.

Tyagi, Sunit Dharamveer

258

An experimental study of a solar receiver for JEM experiment program  

Microsoft Academic Search

A fundamental study was performed to develop a high efficiency solar heat receiver system for a solar energy experiment mission on the Japanese Experiment Module (JEM)-Exposed Facility (EF) of the International Space Station (ISS). This system is aimed to transport solar thermal energy to a bottoming system with a high efficiency. It is composed of a solar heat absorber, thermal

Hitoshi Naito; Tsutomu Fujihara; Takeshi Hoshino; Kunihisa Eguchi; K. Tanaka; Hiroo Yugami

2000-01-01

259

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

260

Enhancing Solar Cell Efficiencies through 1-D Nanostructures  

NASA Astrophysics Data System (ADS)

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.

Yu, Kehan; Chen, Junhong

2009-01-01

261

High efficiency silicon MINP solar cells  

NASA Astrophysics Data System (ADS)

Investigations of high-efficiency MINP silicon solar cells are discussed. Emphasis is placed on cell characterization to develop a basic understanding of current-transport mechanisms which limit cell efficiency. Fabrication and characterization of cells based on 0.2 ohm-cm substrates, diffused emitters 150-200-nm deep, and with Mg MIS collector grids are discussed. A total-area AM1 efficiency of 16.8 percent has been achieved. Detailed analyses of photocurrent and current-loss mechanisms are presented and utilized to predict future directions of research.

Olsen, L. C.; Addis, F. W.; Miller, W. A.; Dunham, G.

262

Experimental study of variations of the solar spectrum of relevance to thin film solar cells  

Microsoft Academic Search

The influence of variations in the incident solar spectrum on solar cells is often neglected. This paper investigates the magnitude of this variation and its potential influence on the performance of thin film solar cells in a maritime climate. The investigation centres on the analysis of a large number of measurements carried out in Loughborough, UK, at 10min intervals over

R. Gottschalg; D. G. Infield; M. J. Kearney

2003-01-01

263

Investigation of utilization solar cell energy for water desalination by reverse osmosis process in the State of Bahrain  

Microsoft Academic Search

Four sets of experiments were conducted to investigate the viability of running a domestic reverse osmosis (RO) unit with solar cell energy. The panel utilised for this purpose consisted of 280 cells, each of approximately 0.008 m in area. Each panel produced 77 to 131 W\\/m over the year, and therefore, the energy output per square metre of solar cells

H. Al-Qahtani

1996-01-01

264

Modeling the Effects of Solar Cell Distribution on Optical Cross Section for Solar Panel Simulation.  

National Technical Information Service (NTIS)

The Air Force Research Laboratory (AFRL) Time-domain Analysis Simulation for Advanced Tracking (TASAT) was used to explore the variation of Optical Cross Section (OCS) with glint angle for a solar panel with different solar cell distribution statistics. S...

K. Feirstine L. Vaughn M. Duggin M. Klein

2012-01-01

265

Assessing the Solar Power Satellite - The OTA experience  

NASA Astrophysics Data System (ADS)

A review of an Office of Technology Assessment examination of SPS potentials and problems as an energy source is presented, along with an examination of the SPS effects on other space systems. The SPS configuration considered included solar cell conversion to klystron transmission to rectennas, with the solid-state converters located on the back of each solar panel. A LEO-based laser system was also explored, along with LEO-based large mirrors to reflect light to selected spots on the earth. A need for the SPS if energy end-use requirements grow to more than 20 quads by the year 2015 was noted, and economic competitiveness with solar technologies and extent of development of the technology was concluded to be on the same level as fusion. Developing the SPS technology was found to offer significant opportunities for advancing U.S. space technology.

Williamson, R. A.; Weisburd, S.; Wasserman, A.

266

18 percent efficient polycrystalline silicon solar cells  

NASA Astrophysics Data System (ADS)

Over the past 7 yr, there has been marked improvements in crystalline silicon solar cell performance, with the highest independently confirmed cell efficiency increasing from 17.1 percent to 24.2 percent. Work directed at transferring some of these improvements to polycrystalline silicon cells is described. Applying a high-efficiency crystalline cell sequence has given efficiencies as high as 17.8 percent with the addition of a phosphorous pretreatment step and modifications of a rear Al alloying step and cell processing temperatures. Surface texturing is identified as an important area requiring attention to obtain the highest possible efficiency. Laser texturing has given the best results to date for polycrystalline substrates. Results are described for a laser-textured, laser-grooved cell processing sequence with the potential to produce polycrystalline cells having efficiencies well above 18 percent.

Narayanan, S.; Zolper, J.; Yun, F.; Wenham, S. R.; Sproul, A. B.

267

Resonant solar neutrino oscillation versus laboratory neutrino oscillation experiments  

SciTech Connect

The interplay between resonant solar neutrino oscillations and neutrino oscillations in laboratory experiments is investigated in a 3 generation model. Due to the assumed hierarchy of neutrino masses, together with our choice of a convenient parameterization of the 3 generation mixing matrix, we can derive a simple analytic formula which reduces the solar neutrino problem to an effective 2 generation problem. The reduction makes it apparent that the allowed range of mixing and mass parameters crucially depend on whether the survival probability of solar neutrinos S satisfies S greater than or equal to 1/3 or not. The formulae for probabilities of laboratory neutrino oscillations are also greatly simplified. We argue that a combination of the observed solar neutrino depletion and data obtained from reactor experiments seems to rule out some range of neutrino masses. If a sizable nu/sub ..mu../ ..-->.. nu/sub e/ oscillation is observed at accelerators, as suggested at this Workshop, it severely restricts the range of 2 mixing angles.

Lim, Chong-Sa

1987-02-01

268

Modeling of high efficiency solar cells under laser pulse for power beaming applications  

NASA Astrophysics Data System (ADS)

Solar cells have been used to convert sunlight to electrical energy for many years and also offer great potential for non-solar energy conversion applications. Their greatly improved performance under monochromatic light compared to sunlight, makes them suitable as photovoltaic (PV) receivers in laser power beaming applications. Laser beamed power to a PV array receiver could provide power to satellites, an orbital transfer vehicle, or a lunar base. Gallium arsenide (GaAs) and indium phosphide (InP) solar cells have calculated efficiencies of more than 50 percent under continuous illumination at the optimum wavelength. Currently high power free-electron lasers are being developed which operate in pulsed conditions. Understanding cell behavior under a laser pulse is important in the selection of the solar cell material and the laser. An experiment by NAsA lewis and JPL at the AVLIS laser facility in Livermore, CA presented experimental data on cell performance under pulsed laser illumination. Reference 5 contains an overview of technical issues concerning the use of solar cells for laser power conversion, written before the experiments were performed. As the experimental results showed, the actual effects of pulsed operation are more complicated. Reference 6 discusses simulations of the output of GaAs concentrator solar cells under pulsed laser illumination. The present paper continues this work, and compares the output of Si and GaAs solar cells.

Jain, Raj K.; Landis, Geoffrey A.

1994-09-01

269

The Borexino Solar Neutrino Experiment: Scintillator purification and surface contamination  

NASA Astrophysics Data System (ADS)

The Borexino Solar Neutrino Experiment will observe the monoenergetic (862 keV) 7Be neutrinos, produced in the solar reaction 7Be+e- ?7 Li+nue. These neutrinos are the second most abundant species of solar neutrinos, with an expected flux at earth of 5 x 109/cm2/s. Using nu - e scattering in an aromatic liquid scintillator, Borexino will make the first real time measurement of the solar neutrino flux at energies less than 1 MeV. In addition to checking Standard Solar Model and neutrino oscillation predictions at low energies, Borexino will test the MSW vacuum-matter transition, luminosity constraint, and non-standard theories such as mass varying neutrinos. The Borexino detector will also be sensitive to supernova neutrinos, geoneutrinos, reactor neutrinos, and pep solar neutrinos. The pep measurement will tightly constrain the primary pp solar neutrino flux whose energy is below the Borexino threshold. With an expected rate of 35 events per day from solar 7Be neutrinos, the maximum tolerable background rate is one count per day. Removal of radioactive isotopes from the liquid scintillator is essential for the experiment's success and will be achieved with purification techniques including filtration, distillation, water extraction, nitrogen stripping, and silica gel adsorption. Results from small-scale purification efficiency tests are presented. Water extraction showed moderate but inadequate removal of 210Po which is a dominant background. Distillation reduced 210Po by a factor of more than 500. Online purification involves cycling over 300 m3 of scintillator from the detector though the purification plants. Flow patterns within the detector that influence the purification efficiency were determined with numerical simulations. Poor flow in the prototype Counting Test Facility showed effectively stagnant volumes within the detector. These are not present in the larger Borexino detector. Surface contamination in Borexino arises primarily from contact with contaminated liquids and the deposition of airborne radon progeny. Measurements of desorption rates showed that surface contaminants are transferred to the scintillator logarithmically with time. Partitioning constants between the scintillator and surfaces were measured and airborne deposition rate of radon progeny in a clean room environment are analyzed. The efficiency of various surface cleaning techniques was also tested.

Leung, Michael

270

Solar cell single measurement maximum power point tracking  

Microsoft Academic Search

It is possible to give a valuable estimation for an entire solar array IV curve, based only on a single working point (current and voltage) measurement, on panels of solar cells, when several of their parameters are known and environmental parameters also known. The estimations were performed using Matlab\\/Simulink and the simulation is based on the 10 parameter solar cell

Raul Rabinovici; Yotam B. Frechter

2010-01-01

271

High performance organic solar cells with interface engineering  

Microsoft Academic Search

Polymer solar cells are considered a promising candidate for renewable energy with low-cost and high volume production capability. The main focus of this dissertation is to investigate the several approaches for improving the efficiency of polymer solar cells. These approaches include understanding of the physics, operation mechanisms, materials and device engineering and optimization of fabrication processes. A typical polymer solar

Mi Hyae Park

2010-01-01

272

Recent advances in sensitized mesoscopic solar cells.  

PubMed

Perhaps the largest challenge for our global society is to find ways to replace the slowly but inevitably vanishing fossil fuel supplies by renewable resources and, at the same time, avoid negative effects from the current energy system on climate, environment, and health. The quality of human life to a large degree depends upon the availability of clean energy sources. The worldwide power consumption is expected to double in the next 3 decades because of the increase in world population and the rising demand of energy in the developing countries. This implies enhanced depletion of fossil fuel reserves, leading to further aggravation of the environmental pollution. As a consequence of dwindling resources, a huge power supply gap of 14 terawatts is expected to open up by year 2050 equaling today's entire consumption, thus threatening to create a planetary emergency of gigantic dimensions. Solar energy is expected to play a crucial role as a future energy source. The sun provides about 120,000 terawatts to the earth's surface, which amounts to 6000 times the present rate of the world's energy consumption. However, capturing solar energy and converting it to electricity or chemical fuels, such as hydrogen, at low cost and using abundantly available raw materials remains a huge challenge. Chemistry is expected to make pivotal contributions to identify environmentally friendly solutions to this energy problem. One area of great promise is that of solar converters generally referred to as "organic photovoltaic cells" (OPV) that employ organic constituents for light harvesting or charge carrier transport. While this field is still in its infancy, it is receiving enormous research attention, with the number of publications growing exponentially over the past decade. The advantage of this new generation of solar cells is that they can be produced at low cost, i.e., potentially less than 1 U.S. $/peak watt. Some but not all OPV embodiments can avoid the expensive and energy-intensive high vacuum and materials purification steps that are currently employed in the fabrication of all other thin-film solar cells. Organic materials are abundantly available, so that the technology can be scaled up to the terawatt scale without running into feedstock supply problems. This gives organic-based solar cells an advantage over the two major competing thin-film photovoltaic devices, i.e., CdTe and CuIn(As)Se, which use highly toxic materials of low natural abundance. However, a drawback of the current embodiment of OPV cells is that their efficiency is significantly lower than that for single and multicrystalline silicon as well as CdTe and CuIn(As)Se cells. Also, polymer-based OPV cells are very sensitive to water and oxygen and, hence, need to be carefully sealed to avoid rapid degradation. The research discussed within the framework of this Account aims at identifying and providing solutions to the efficiency problems that the OPV field is still facing. The discussion focuses on mesoscopic solar cells, in particular, dye-sensitized solar cells (DSCs), which have been developed in our laboratory and remain the focus of our investigations. The efficiency problem is being tackled using molecular science and nanotechnology. The sensitizer constitutes the heart of the DSC, using sunlight to pump electrons from a lower to a higher energy level, generating in this fashion an electric potential difference, which can exploited to produce electric work. Currently, there is a quest for sensitizers that achieve effective harnessing of the red and near-IR part of sunlight, converting these photons to electricity better than the currently used generation of dyes. Progress in this area has been significant over the past few years, resulting in a boost in the conversion efficiency of the DSC that will be reviewed. PMID:19715294

Grätzel, Michael

2009-11-17

273

Carbon dioxide retrievals from Atmospheric Chemistry Experiment solar occultation measurements  

Microsoft Academic Search

The Atmospheric Chemistry Experiment (ACE) satellite (SCISAT-1) was launched into an inclined orbit on 12 August 2003 and is now recording high signal-to-noise 0.02 cm?1 resolution solar absorption spectra covering 750–4400 cm?1 (2.3–13 ?m). A procedure has been developed for retrieving average dry air CO2 mole fractions (XCO2) in the altitude range 7–10 km from the SCISAT-1 spectra. Using the

Curtis P. Rinsland; Linda S. Chiou; Chris Boone; Peter Bernath

2010-01-01

274

Improved efficiency silicon solar cell module  

SciTech Connect

This paper describes a solar cell module efficiency of 22.3% independently measured at Sandia National Laboratories. This the highest ever confirmed efficiency for a photovoltaic module of this size achieved by cells made on any material. This 787-cm{sup 2} module used 40 large-area double-layer antireflection coated PERL (passivated emitter, rear locally-diffused) silicon cells of average efficiency of 23.1%. The double-layer coating, together with an improved cell structure and a shingled encapsulation technique, considerably contributed to this efficiency improvement. Also reported is an independently confirmed efficiency of 23.7% for a 21.60-cm{sup 2} cell of the type used in the module, the highest efficiency ever reported for a silicon cell of this size.

Zhao, J.; Wang, A.; Abbaspour-Sani, E.; Yun, F.; Green, M.A. [Univ. of New South Wales, Sydney (Australia). Photovoltaics Special Research Centre

1997-02-01

275

MANUFACTURE OF PHOTOVOLTAIC SOLAR CELL USING PLANT CHLOROPHYLL  

EPA Science Inventory

To date, we have successfully manufactured working chlorophyll sensitized solar cells using chlorophyll (and b mixture) from spinach leaves. We have evaluated the electronic characteristics (voltage, current, and power outputs using different loading resistors) of this solar c...

276

Research Profiling: Nano-enhanced, Thin-film Solar Cells  

Microsoft Academic Search

Nanotechnology-enhanced thin-film solar cells constitute one of the most promising solar energy solutions and an important currently emerging application of nanotechnology. This paper profiles the research patterns via \\

Ying Guo; Lu Huang; Alan L. Porter

277

Improved Solar Cells Testing Fixtures.  

National Technical Information Service (NTIS)

A rotating platform which can lock, connect and test the electrical parameters of two cells, locating them in the same position under the light beam, is described. Multi-filter spectral response equipment which operates in combination with the platform is...

G. Sala J. Aguilera J. C. Zamorano E. Sanchez A. M. Grass

1989-01-01

278

Chalcopyrite thin film solar cells by electrodeposition  

Microsoft Academic Search

This paper reviews the state of the art in using electrodeposition to prepare chalcopyrite absorber layers in thin film solar cells. Most of the studies deal with the direct preparation of Cu(In,Ga)Se2 films, and show that the introduction of gallium in the films is now becoming possible from single bath containing all the elements. Electrodeposition can also be used to

D. Lincot; J. F. Guillemoles; S. Taunier; D. Guimard; J. Sicx-Kurdi; A. Chaumont; O. Roussel; O. Ramdani; C. Hubert; J. P. Fauvarque; N. Bodereau; L. Parissi; P. Panheleux; P. Fanouillere; N. Naghavi; P. P. Grand; M. Benfarah; P. Mogensen; O. Kerrec

2004-01-01

279

Microcrystalline organic thin-film solar cells.  

PubMed

Microcrystalline organic films with tunable thickness are produced directly on an indium-tin-oxide substrate, by crystallizing a thin amorphous rubrene film followed by its use as a template for subsequent homoepitaxial growth. These films, with exciton diffusion lengths exceeding 200 nm, produce solar cells with increasing photocurrents at thicknesses up to 400 nm with a fill factor >65%, demonstrating significant potential for microcrystalline organic electronic devices. PMID:23939936

Verreet, Bregt; Heremans, Paul; Stesmans, Andre; Rand, Barry P

2013-08-13

280

Materials availability for thin film solar cells  

Microsoft Academic Search

Materials availability is one of the most important factors when we consider the mass-production of next generation photovoltaic devices. ``In (indium)'' is a vital element to produce high efficient thin film solar cells such as InP and CuIn(Ga)Se2 but its lifetime as a natural resource is suggested to be of order of 10~15 years. The lifetime of a specific natural

Yunosuke Makita

1997-01-01

281

Aluminum arsenide eutectic gallium arsenide solar cell  

Microsoft Academic Search

An improved gallium arsenide solar cell is provided by forming a P+ layer on top of a wafer of vertical PN junction eutectic gallium arsenide crystal by liquid phase epitaxial growth of P doped GaAs followed by liquid phase epitaxial growth at Al(x)AsGa(1-x) on the surface of the vertical PN junction substrate. The deposited GaAs layer with P dopant and

Rahilly

1976-01-01

282

Aluminum arsenide eutectic gallium arsenide solar cell  

Microsoft Academic Search

An improved gallium arsenide solar cell is provided by forming a P + layer on top of a wafer of plural vertical PN junction eutectic gallium arsenide crystal by liquid phase epitaxial growth of P doped GaAs followed by liquid phase epitaxial growth at Al\\/sub x\\/AsGa\\/sub l-x\\/ on the surface of the vertical PN junction substrate. The deposited GaAs layer

Rahilly

1978-01-01

283

Solar cell array with lightweight support structure  

Microsoft Academic Search

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

Gounder

1983-01-01

284

Solar-hydrogen fuel-cell vehicles  

Microsoft Academic Search

Hydrogen is an especially attractive transportation fuel. It is the least populating fuel available, and can be produced anywhere there is water and a clean source of electricity. A fuel cycle in which hydrogen is produced by solar-electrolysis of water, or by gasification of renewably grown biomass, and then used in a fuel-cell powered electric-motor vehicle (FCEV), would produce little

Mark A. DeLuchi; Joan M. Ogden

1993-01-01

285

Efficient CIGS solar cells prepared by electrodeposition  

Microsoft Academic Search

Cu(In,Ga)Se\\/sub 2\\/\\/CdS\\/ZnO cells with efficiencies close to 19% have been obtained with films prepared by coevaporation of the elements. Electrodeposition has the potential to become a suitable method for large production of CIGS solar modules. In this paper, we present the results of an on going collaboration project, between CNRS-ENSCP, EDF (Electricite de France) and SUR (Saint Gobain Recheche) with

D. Guimard; N. Bodereau; J. Kurdi; J. F. Guillemoles; D. Lincot; P. P. Grand; M. BenFarrah; S. Taunier; O. Kerrec; P. Mogensen

2003-01-01

286

Health effects of solar cell component material.  

PubMed

Owing to the increasing interest being paid to the issue of the global environment, the production of solar cells has increased rapidly in recent years. Copper indium gallium diselenide (CIGS) is a new efficient thin film used in some types of solar cell. Indium is a constitutive element of CIGS thin-film solar cells. It was thought that indium compounds were not harmful until the beginning of the 1990s because there was little information regarding the adverse health effects on humans or animals arising from exposure to indium compounds. After the mid-1990s, data became available indicating that indium compounds can be toxic to animals. In animal studies, it has been clearly demonstrated that indium compounds cause pulmonary toxicity and that the dissolution of indium compounds in the lungs is considerably slow, as shown by repeated intratracheal instillations in experimental animals. Thus, it is necessary to pay much greater attention to human exposure to indium compounds, and precautions against possible exposure to indium compounds are paramount with regard to health management. PMID:23718969

Tanaka, Akiyo; Hirata, Miyuki

2013-01-01

287

Squaraine donor based organic solar cells  

NASA Astrophysics Data System (ADS)

There are three main ongoing avenues to improve the power conversion efficiency of organic photovoltaics (OPV): the development of new organic materials, improved process control and novel device architecture design. In this thesis, through molecular design with chemical modification of functional organic molecules, a family of new highly absorptive solution processable squaraine (SQ) materials have been systematically synthesized and explored to improve the sunlight harvesting and charge transport. The spin-cast SQ donors are then coated with fullerene acceptors to form a unique nanocrystalline heterojunction (NcHJ) OPV device. This combination of a novel and efficient family of SQ donors, a unique NcHJ device architecture and optimized fabrication processes leads to high efficiency solar cells. For example, solar cells with efficiencies of ˜5.7 % and a fill factor ˜0.74 are achieved. We find a correlation between solar cell fill factor with the SQ thin film density, providing support for the molecular design concept that planar end groups result in close intermolecular stacking, and hence improved charge transport and exciton diffusion. Finally, thermal annealing of the films results in the formation of nanocrystalline morphologies that lead to further improvements in device performance. The microcrystal growth of SQ donors have been characterized by XRD, AFM and TEM.

Wei, Guodan

288

CRLS-229 solar X-ray spectrometer/spectroheliograph experiment  

NASA Astrophysics Data System (ADS)

The CRLS-229 solar X-ray spectrometer/spectroheliograph payload was launched in the solar pointed section of the U.S. Air Force Space Test Program P78-1 satellite on 24 February 1979. The payload consists of two instruments furnished by the Aerospace Corporation, known as SOLEX and MONEX, and two instruments furnished by the Naval Research Laboratory. The SOLEX instrument provides maps of the sun in individual X-ray spectral lines and also obtains spectra in the 3 to 25 A wavelength interval while pointed at a specific solar region. The basic SOLEX hardware consists of two multigrid collimators with 20 arc sec and 60 arc sec spatial resolution, RAP and ADP scanning high resolution Bragg crystals, and a proportional counter and an array of channel electron multipliers as detectors. The MONEX experiment, consisting of two proportional counters, provides full disk solar X-ray intensity with moderate spectral resolution and excellent temporal resolution in the 1 to 140 keV energy interval. Examples of data from the spectrometer/spectroheliograph are presented.

Landecker, P. B.; McKenzie, D. L.; Rugge, H. R.

1979-01-01

289

High temperature-high current solar cells for thermophotovoltaic systems  

SciTech Connect

The conditions under which a photovoltaic cell operates in a thermophotovoltaic system are examined. The design of solar cells capable of operating under these conditions is then formulated and the efficiency of such cells is computed. It is shown that efficiencies in excess of 40% are possible in silicon p-n junction solar cells.

Neville, R.C.

1982-01-01

290

On-orbit demonstration of GaAs solar cell and panel technologies  

Microsoft Academic Search

Phase one of the GaAs Solar Array Experiment Adaptation for in-orbit TDP (technological demonstration program) is described. Results of the experiment foresee the launching of a 30 W GaAs flight panel powering a scientific satellite for a two year low earth orbit mission. Nine hundred 4 cm squared and twenty 16 cm squared GaAs solar cells were produced and assembled

C. Flores; F. Paletta; L. Brambilla; A. Caon; R. Contini; R. Gajo; E. Rossi; C. Signorini; R. L. Crabb

1989-01-01

291

First space flight of InP solar cells  

Microsoft Academic Search

A large-scale, commercial process to produce high-efficiency diffused junction InP solar cells is developed. Proton irradiation effects on InP solar cells are also studied. Superior proton resistance of InP cells is confirmed by defect analysis. 1300 pieces of InP solar cells (2×1 cm2), with efficiencies of 16-17%, were used as the power source for the lunar orbiter of the Japanese

M. Yamaguchi; T. Hayashi; A. Ushirokawa; Y. Takahashi; M. Koubata; M. Hashimoto; S. Ikegami; H. Arai; T. Orii; H. Okazaki; T. Takamoto; M. Ura; M. Ohmori

1990-01-01

292

Saturation current in solar cells - An analysis  

NASA Astrophysics Data System (ADS)

An analysis of the saturation current in solar cells indicates that the factor A in the Shockley equation is material independent and has a constant value of 2.95 x 10 to the 5th A per sq cm of the cell. The saturation current, I(0), and a fundamental solid state parameter, the 0 K Debye temperature, are explicitly correlated on the basis of the work of Ravindra and Srivastava (1979). It is shown that dLnI(0)/dT increases with the energy gap at 0 K.

Ravindra, N. M.

1980-10-01

293

Variation of solar cell sensitivity and solar radiation on tilted surfaces  

Microsoft Academic Search

An empirical study was performed (1) to evaluate the validity of various insolation models used to compute solar radiation incident on tilted surfaces from global data measured on horizontal surfaces and (2) to determine the variation of solar cell sensitivity to solar radiation over a wide range of atmospheric condition. Evaluation of the insolation data indicates that the isotropic sky

T. M. Klucher

1978-01-01

294

Technical use of solar energy. Part 1. Thin films solar cells  

Microsoft Academic Search

Due to the potentialities of Cu2-xS-CdS thin film solar cells, several companies installed production lines for this type of solar cell. Besides investigations for further enhancing efficiency and long-term stability, for gaining data of physical and electronical parameters, and for improving the theoretical knowledge of the cell, materials and technologies are investigated which look promising for large-scale industrial production. Solar

W. Arndt; G. H. Bauer; H. U. Berger; W. H. Bloss; G. H. Hewig; F. Pfisterer; H. W. Schock

1983-01-01

295

Calculation of the Performance of Solar Cells With Spectral Down Shifters Using Realistic Outdoor Solar Spectra  

Microsoft Academic Search

Spectral down converters and shifters have been proposed as a good means to enhance the efficiency of underlying solar cells. In this paper, we focus on the simulation of the outdoor performance of solar cells with spectral down shifters, i.e., multicrystalline silicon solar cells with semiconductor nanocrystals as wavelength-shifting material. Daily and\\u000aannual performance of these devices can be simulated

W. G. J. H. M. van Sark

2007-01-01

296

Thin film polycrystalline silicon solar cells  

SciTech Connect

During the present quarter efficiency of heterostructure solar cells has been increased from 13 to 13.7% for single crystal and from 10.3 to 11.2% for polysilicon. For polysilicon the improvements can be attributed to reductions in grid-area coverage and in reflection losses and for single crystal to a combination of reduction in grid-area coverage and increase in fill factor. The heterostructure cells in both cases were IT0/n-Si solar cells. Degradation in Sn0/sub 2//n-Si solar cells can be greatly reduced to negligible proportions by proper encapsulation. The cells used in stability tests have an average initial efficiency of 11% which reduces to a value of about 10.5% after 6 months of exposure to sunlight and ambient conditions. This small degradation occurs within the first month, and the efficiency remains constant subsequently. The reduction in efficiency is due to a decrease in the open-circuit voltage only, while the short-circuit current and fill factor remain constant. The effects of grain-size on the Hall measurements in polysilicon have been analyzed and interpreted, with some modifications, using a model proposed by Bube. This modified model predicts that the measured effective Hall voltage is composed of components originating from the bulk and space-charge region. For materials with large grains, the carrier concentration is independent of the inter-grain boundary barrier, whereas the mobility is dependent on it. However, for small rains, both the carrier density and mobility depend on the barrier. These predictions are consistant with experimental results of mm-size Wacker polysilicon and ..mu..m-size NTD polysilicon.

Ghosh, A. K.; Feng, T.; Eustace, D. J.; Maruska, H. P.

1980-01-01

297

Solar cell angle of incidence corrections  

NASA Astrophysics Data System (ADS)

Literature on solar array angle of incidence corrections was found to be sparse and contained no tabular data for support. This lack along with recent data on 27 GaAs/Ge 4 cm by 4 cm cells initiated the analysis presented in this paper. The literature cites seven possible contributors to angle of incidence effects: cosine, optical front surface, edge, shadowing, UV degradation, particulate soiling, and background color. Only the first three are covered in this paper due to lack of sufficient data. The cosine correction is commonly used but is not sufficient when the incident angle is large. Fresnel reflection calculations require knowledge of the index of refraction of the coverglass front surface. The absolute index of refraction for the coverglass front surface was not known nor was it measured due to lack of funds. However, a value for the index of refraction was obtained by examining how the prediction errors varied with different assumed indices and selecting the best fit to the set of measured values. Corrections using front surface Fresnel reflection along with the cosine correction give very good predictive results when compared to measured data, except there is a definite trend away from predicted values at the larger incident angles. This trend could be related to edge effects and is illustrated by a use of a box plot of the errors and by plotting the deviation of the mean against incidence angle. The trend is for larger deviations at larger incidence angles and there may be a fourth order effect involved in the trend. A chi-squared test was used to determine if the measurement errors were normally distributed. At 10 degrees the chi-squared test failed, probably due to the very small numbers involved or a bias from the measurement procedure. All other angles showed a good fit to the normal distribution with increasing goodness-of-fit as the angles increased which reinforces the very small numbers hypothesis. The contributed data only went to 65 degrees from normal which prevented any firm conclusions about extreme angle effects although a trend in the right direction was seen. Measurement errors were estimated and found to be consistent with the conclusions that were drawn. A controlled experiment using coverglasses and cells from the same lots and extending to larger incidence angles would probably lead to further insight into the subject area.

Burger, Dale R.; Mueller, Robert L.

1995-10-01

298

High intensity solar cell invention: The edge-illuminated vertical multi-junction (VNJ) solar cell. Final report.  

National Technical Information Service (NTIS)

This report contains a summary of a High Intensity Solar Cell (HI Cell) development carried out under the NIST/DOE Energy-Related Invention Program. The HI Cell, or Edge-Illuminated vertical Multi-junction Solar Cell, eliminates most major problems encoun...

B. L. Sater

1992-01-01

299

Calibration of solar simulator for evaluation of dye-sensitized solar cells  

Microsoft Academic Search

The photo-to-electricity energy conversion efficiencies of ruthenium-dye-sensitized solar cells (DSC) are measured under a solar simulator. The error in conversion efficiencies was compared under a variety of spectral conditions. Measurements of the conversion efficiencies of DSC between a solar simulator and outdoor sunlight result in about 10% error. This error was seen when the spectral intensity of a xenon-lamp solar

Seigo Ito; Hiroshi Matsui; Ken-ichi Okada; Sei-ichi Kusano; Takayuki Kitamura; Yuji Wada; Shozo Yanagida

2004-01-01

300

Vapor CdCl2-Optimization and Screening Experiments for an All Dry Chloride Treatment of CdS/CdTe Solar Cells  

SciTech Connect

A dry vapor treatment of CdCl2 is being developed as an alternative approach to the conventional solution CdCl2 treatment of CdS/CdTe devices. In this alternative process, the CdS/CdTe substrates are vapor treated in a close-spaced sublimation configuration. A 16-run Plackett-Burman screening experiment identified source temperature, substrate temperature, and treatment time as being the most significant parameters in the process. Subsequently, a 20-run Central Composite Design showed that a source temperature of 380-390 C, a temperature gradient (DT) of 5 C, and a time of 10 minutes provides the most process tolerant combination, yielding a total-area efficiency of 12.6%. A strong interaction between DT and treatment time was also identified. The model indicated that for a small DT, device performance improved with decreasing time, whereas at larger values of DT, performance increased with increasing time.

Mahathongdy, Y.; Wolden, C. A.; Baldwin, R. M. (Colorado School of Mines, Golden, CO); Albin, D. S. (National Renewable Energy Laboratory)

1998-10-01

301

Solar module having reflector between cells  

DOEpatents

A photovoltaic module comprising an array of electrically interconnected photovoltaic cells disposed in a planar and mutually spaced relationship between a light-transparent front cover member in sheet form and a back sheet structure is provided with a novel light-reflecting means disposed between adjacent cells for reflecting light falling in the areas between cells back toward said transparent cover member for further internal reflection onto the solar cells. The light-reflecting comprises a flexible plastic film that has been embossed so as to have a plurality of small V-shaped grooves in its front surface, and a thin light-reflecting coating on said front surface, the portions of said coating along the sides of said grooves forming light-reflecting facets, said grooves being formed so that said facets will reflect light impinging thereon back into said transparent cover sheet with an angle of incidence greater than the critical angle, whereby substantially all of the reflected light will be internally reflected from said cover sheet back to said solar modules, thereby increasing the current output of the module.

Kardauskas, Michael J. (Billerica, MA)

1999-01-01

302

Substrate Configuration Cadmium Telluride Solar Cells  

NASA Astrophysics Data System (ADS)

Cadmium telluride/cadmium sulfide substrate type thin-film solar cells were fabricated on 0.1 mm thick molybdenum and stainless steel substrates. The deposition method was radio frequency plasma sputtering in argon at pressures of 10 - 20 mTorr. The structure was: substrate/(ZnTe:N)/CdTe/CdS/TCO. The Transparent Conducting Oxide (TCO) was ITO or ZnO:Al. This is an inverted configuration compared to the conventional glass/TCO/CdS/CdTe/contact devices. Solar cells on Mo substrates exhibited up to 7.8(the highest value reported so far for this type of devices) and the cells on stainless steel or with ZnO:Al were about 3above 70shape at the red and blue edges of the spectrum show that there is less CdTe-CdS interdiffusion during the post-growth heat treatment compared to the conventional superstrate cells. This is attributed to the fully developed CdTe grains at the CdTe-CdS interface. Also, the current is limited at voltages above 0.8 V which indicates a back-diode effect at the metal-CdTe or CdS-TCO interface. Supported by the National Renewable Energy Laboratory.

Matulionis, Ilvydas

2002-03-01

303

Recent Advances in Sensitized Solar Cells  

NASA Astrophysics Data System (ADS)

Understanding the principal physical and chemical factors that govern or limit cell performance is critical for underpinning the development of next-generation sensitized solar cells. Recent studies of dye-sensitized solar cells (DSSCs) covering nanoporous (pore diameter <100 nm) one-dimensional TiO2 nanostructured arrays and molecular voltage enhancers are discussed. Films constructed of oriented one-dimensional nanostructures, such as nanotube arrays, which are aligned perpendicularly to the charge-collecting substrate, could potentially improve the charge-collection efficiency by promoting faster transport and/or slower recombination. The extent to which transport or recombination could be affected by an oriented architecture is expected to depend on the influence of other mechanistic factors, such as the density and location of defects, crystallinity, and film uniformity. Orientational disorder within the nanotube array could also influence the transport and recombination kinetics. Such architectural disorder in titanium dioxide films is shown to have a strong influence on the transport, recombination, and light-harvesting properties of DSSCs. The mechanism by which molecular adsorbents alter the photovoltage of DSSCs is dependent on the properties of the adsorbent. In principle, an adsorbent could affect the photovoltage by either altering the recombination rate of photoelectrons in TiO2 with oxidized redox species in the electrolyte or inducing band-edge movement. The net effect of altering the band positions and recombination kinetics can either improve or diminish cell performance. The mechanisms by which several molecular adsorbents increase the photovoltage of DSSCs are discussed.

Frank, Arthur J.

304

High efficiency, radiation-hard solar cells  

SciTech Connect

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

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

2004-10-22

305

Demonstration Experiment for Tethered-Solar Power Satellite  

NASA Astrophysics Data System (ADS)

The technologies for the Solar Power Satellite (SPS) have been well studied on the ground and now it is highly required to make demonstration experiments in space as the next logical step. One of the important subjects to be verified in space is the microwave power transmission pointing at the rectenna site on the ground. It includes verification of high-power microwave power transmission through the ionosphere and demonstration of the retro-directive phase control technology for the microwave beaming. These studies can be conducted by the “Small Satellite” that is currently promoted as one of the near future space programs in Japan. The conceptual study for the demonstration experiment has shown that 1 kW class microwave power transmission experiment at 5.8 GHz in the low earth orbit is worthwhile and feasible under constraints of current concept of the “Small Satellite” program.

Sasaki, Susumu; Tanaka, Koji

306

POSS® Coatings as Replacements for Solar Cell Cover Glasses  

Microsoft Academic Search

Presently, solar cells are covered with Ce-doped microsheet cover glasses that are attached with Dow Corning DC 93500 silicone adhesive. This general approach has been used from the beginning of space exploration, however, it is expensive and time consuming. Furthermore, as the voltage of solar arrays increases, significant arcing has occurred in solar arrays, leading to loss of satellite power.

Henry Brandhorst; Tamara Isaacs-Smith; Brian Wells; Joseph D. Lichtenhan; Bruce X. Fu

2006-01-01

307

Recent progress of amorphous silicon solar cell technology in Japan  

Microsoft Academic Search

The current state of the art in Japanese activities in amorphous silicon solar cell R&D is reviewed. First, a change of the organization in the Sunshine Project is introduced. Second, some novel approaches and key technologies to improve solar cell efficiency with stabilized performance with amorphous materials such as a-SiC:H, ?c-SiC:H, a-SiGe:H, and their heterojunction and stacked solar cells are

Yoshihiro HAMAKAWA

1991-01-01

308

The CdTe Thin Film Solar Cell - AN Overview  

Microsoft Academic Search

The basic physical aspects of the CdTe-thin film solar cell in its various embodiments are reviewed. Deposition techniques are briefly described, results of present pilot-line production efforts and the future potential are discussed, which make the CdTe thin film solar cell a promising candidate for low cost and well-above 10% module-efficiency. A detailed costing model for thin film solar cells

Dieter Bonnet

1992-01-01

309

DOE\\/NREL fundamental and exploratory research into solar cells  

Microsoft Academic Search

The U.S. Department of Energy\\/National Renewable Energy Laboratory supports fundamental and exploratory research into solar cells. The purpose of the following set of research projects is twofold: (1) to provide fundamental experimental and theoretical foundations to existing photovoltaic (PV)\\/solar cell technologies, and (2) to explore whole new possibilities in PV\\/solar cell technologies, however revolutionary or nonconventional they might be. As

Richard Matson; Robert McConnell

2002-01-01

310

Metamorphic and Lattice-Matched Solar Cells Under Concentration  

Microsoft Academic Search

Metamorphic III-V semiconductor materials offer access to bandgaps that span key portions of the solar spectrum, enabling new bandgap combinations in multijunction solar cells, and increasing both theoretical and practical efficiency limits for terrestrial concentrator cells. Experimental results are given for the quantum efficiency of metamorphic GaInAs solar cells with bandgap from 1.1 to 1.4 eV, and for metamorphic GaInP

R. R. King; D. C. Law; K. M. Edmondson; C. M. Fetzer; R. A. Sherif; G. S. Kinsey; D. D. Krut; H. L. Cotal; N. H. Karam

2006-01-01

311

New generation of space batteries--GaAs solar cells  

SciTech Connect

This paper describes a new generation of space power sources, GaAs solar cells, and the status of their development inside China and abroad. In conjunction with this, on the basis of unique properties associated with GaAs solar cells, it points out the direction of development, clarifies the value of key space applications, and, finally, forecasts the application prospects for GaAs solar cells.

Zhang, Z.; Shi, W.

1995-05-15

312

Polymer\\/Metal Oxide Nanocrystals Hybrid Solar Cells  

Microsoft Academic Search

In this paper, we present two different types of polymer\\/metal oxide nanocrystals hybrid photovoltaics. One is the poly(3-hexylthiophene) (P3HT)\\/TiO2 nanorods hybrid bulk heterojunction (BHJ) solar cell and the other is a nanostructured ZnO\\/P3HT hybrid solar cell. In a BHJ hybrid solar cell, the dispersed semiconducting nanocrystals lead to an increased interface area between polymer and nanocrystals, which can assist charge

Shao-Sian Li; Yun-Yue Lin; Wei-Fang Su; Chun-Wei Chen

2010-01-01

313

Multijunction Solar Cell Technology for Mars Surface Applications  

Microsoft Academic Search

Solar cells used for Mars surface applications have been commercial space qualified AMO optimized devices. Due to the Martian atmosphere, these cells are not optimized for the Mars surface and as a result operate at a reduced efficiency. A multi-year program, MOST (Mars Optimized Solar Cell Technology), managed by JPL Science Mission Directorate (SMD) and funded by NASA Code S,

Paul M. Stella; Nick Mardesich; Richard C. Ewell; Robert L. Mueller; Scott Endicter; Daniel Aiken; Kenneth Edmondson; Chris Fetzer

2006-01-01

314

Solar energy powered microbial fuel cell with a reversible bioelectrode  

Microsoft Academic Search

The solar energy powered microbial fuel cell is an emerging technology for electricity generation via electrochemically active microorganisms fueled by solar energy via in situ photosynthesized metabolites from algae, cyanobacteria, or living higher plants. A general problem with microbial fuel cells is the pH membrane gradient which reduces cell voltage and power output. This problem is caused by acid production

David P. B. T. B. Strik; Hubertus V. M. Hamelers; Cees J. N. Buisman

2010-01-01

315

A microprocessor-based instrument for automatic solar cell characterization  

Microsoft Academic Search

A system which digitally records solar cell performance parameters is discussed and the design of a microcomputer based measurement system for solar cells is described. The key parameter is the current-voltage characteristic, assayed by sweeping the bias voltage to vary the cell output voltage from zero to the open circuit value at a load resistance which is varied to values

G. C. Cardinali; E. Faldella

1982-01-01

316

Characterization of production GaAs solar cells for space  

SciTech Connect

The electrical performance of GaAs solar cells was characterized as a function of irradiation with protons and electrons with the underlying goal of producing solar cells suitable for use in space. Proton energies used varied between 50 keV and 10 MeV, and damage coefficients were derived for liquid phase epitaxy GaAs solar cells. Electron energies varied between 0.7 and 2.4 MeV. Cells from recent production runs were characterized as a function of electron and proton irradiation. These same cells were also characterized as a function of solar intensity and operating temperature, both before and after the electron irradiations. The long term stability of GaAs cells during photon exposure was examined. Some cells were found to degrade with photon exposure and some did not. Calibration standards were made for GaAs/Ge solar cells by flight on a high altitude balloon.

Anspaugh, B.E.

1988-12-01

317

Consciousness can reduce the voltage of the output signal of solar cell  

Microsoft Academic Search

When the sun's light radiate on the solar cell, the solar cell can produce the output signal as the photocurrent. We use the Data Acquisition Modules to record the voltage of the output signals. The v1 is voltage of the output signal of solar cell1; The v2 is the one of solar cell2. And these two solar cells stay side

Dayong Cao

2010-01-01

318

Consciousness can reduce the voltage of the output signal of solar cell  

NASA Astrophysics Data System (ADS)

When the sun's light radiate on the solar cell, the solar cell can produce the output signal as the photocurrent. We use the Data Acquisition Modules to record the voltage of the output signals. The v1 is voltage of the output signal of solar cell1; The v2 is the one of solar cell2. And these two solar cells stay side by side. When we record the voltage of the output signal from the morning to the noon, the voltage of the output signals will go up, and the v1 is bigger than the v2 during this time. But when the experimenter use consciousness to reduce the voltage of the output signals. That is to say: not only natural light ratiade on two solar cells, but also consciousness act on two solar cells. Not only I can use consciousness to reduce the growth voltage of the output signals, but also can change the v1 to be littler than the v2. The experiment was conducted on Sep. 2010. There is the physical system of the mass, energy, space and time-MEST; There is the spirited system of the mind, consciousness, emotion and desire-MECD; the information system is the code system. We can use them to develop photoelectric principle, life technology and Nanotech of semiconductor for consciousness effect.

Cao, Dayong

2010-10-01

319

LEO effects on candidate solar cell cover materials  

NASA Astrophysics Data System (ADS)

In 1984, the LDEF (Long Duration Exposure Facility) was placed in LEO (Low Earth Orbit) for a mission planned to last approximately one year. Due to a number of factors, retrieval was delayed until 1990. An experiment, prepared under the direction of JPL, consisted of a test plate with thirty (30) individual thin silicon solar cell/cover samples. The covers consisted of conventional cerium doped microsheet platelets and potential candidate materials, such as FEP Teflon, silicon RTV's, glass resins, polyimides, and a silicone-polyimide copolymer encapsulant. The effects of the LDEF mission environment (micrometeorite/debris impacts, atomic oxygen, UV, and particulate radiation) on the samples are discussed.

Stella, Paul M.

1993-04-01

320

Recyclable organic solar cells on cellulose nanocrystal substrates  

PubMed Central

Solar energy is potentially the largest source of renewable energy at our disposal, but significant advances are required to make photovoltaic technologies economically viable and, from a life-cycle perspective, environmentally friendly, and consequently scalable. Cellulose nanomaterials are emerging high-value nanoparticles extracted from plants that are abundant, renewable, and sustainable. Here, we report on the first demonstration of efficient polymer solar cells fabricated on optically transparent cellulose nanocrystal (CNC) substrates. The solar cells fabricated on the CNC substrates display good rectification in the dark and reach a power conversion efficiency of 2.7%. In addition, we demonstrate that these solar cells can be easily separated and recycled into their major components using low-energy processes at room temperature, opening the door for a truly recyclable solar cell technology. Efficient and easily recyclable organic solar cells on CNC substrates are expected to be an attractive technology for sustainable, scalable, and environmentally-friendly energy production.

Zhou, Yinhua; Fuentes-Hernandez, Canek; Khan, Talha M.; Liu, Jen-Chieh; Hsu, James; Shim, Jae Won; Dindar, Amir; Youngblood, Jeffrey P.; Moon, Robert J.; Kippelen, Bernard

2013-01-01

321

Direct Write Contacts for Solar Cells  

SciTech Connect

Ag, Cu, and Ni metallizations were inkjet-printed with near-vacuum deposition quality. The approach developed can be easily extended to other conductors such as Pt, Pd, and Au. 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 the silicon nitride antireflective layer at 850 C resulting in 8%-efficient cells. Next-generation multicomponent inks (including etching agents) have also been developed with improved fire-through contacts leading to higher cell efficiencies. PEDOT-PSS polymer-based conductors were inkjet-printed with conductivity as good or better than that of spin-coated films.

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

2005-02-01

322

Elongated nanostructures for radial junction solar cells.  

PubMed

In solar cell technology, the current trend is to thin down the active absorber layer. The main advantage of a thinner absorber is primarily the reduced consumption of material and energy during production. For thin film silicon (Si) technology, thinning down the absorber layer is of particular interest since both the device throughput of vacuum deposition systems and the stability of the devices are significantly enhanced. These features lead to lower cost per installed watt peak for solar cells, provided that the (stabilized) efficiency is the same as for thicker devices. However, merely thinning down inevitably leads to a reduced light absorption. Therefore, advanced light trapping schemes are crucial to increase the light path length. The use of elongated nanostructures is a promising method for advanced light trapping. The enhanced optical performance originates from orthogonalization of the light's travel path with respect to the direction of carrier collection due to the radial junction, an improved anti-reflection effect thanks to the three-dimensional geometric configuration and the multiple scattering between individual nanostructures. These advantages potentially allow for high efficiency at a significantly reduced quantity and even at a reduced material quality, of the semiconductor material. In this article, several types of elongated nanostructures with the high potential to improve the device performance are reviewed. First, we briefly introduce the conventional solar cells with emphasis on thin film technology, following the most commonly used fabrication techniques for creating nanostructures with a high aspect ratio. Subsequently, several representative applications of elongated nanostructures, such as Si nanowires in realistic photovoltaic (PV) devices, are reviewed. Finally, the scientific challenges and an outlook for nanostructured PV devices are presented. PMID:24088584

Kuang, Yinghuan; Vece, Marcel Di; Rath, Jatindra K; Dijk, Lourens van; Schropp, Ruud E I

2013-10-03

323

Elongated nanostructures for radial junction solar cells  

NASA Astrophysics Data System (ADS)

In solar cell technology, the current trend is to thin down the active absorber layer. The main advantage of a thinner absorber is primarily the reduced consumption of material and energy during production. For thin film silicon (Si) technology, thinning down the absorber layer is of particular interest since both the device throughput of vacuum deposition systems and the stability of the devices are significantly enhanced. These features lead to lower cost per installed watt peak for solar cells, provided that the (stabilized) efficiency is the same as for thicker devices. However, merely thinning down inevitably leads to a reduced light absorption. Therefore, advanced light trapping schemes are crucial to increase the light path length. The use of elongated nanostructures is a promising method for advanced light trapping. The enhanced optical performance originates from orthogonalization of the light's travel path with respect to the direction of carrier collection due to the radial junction, an improved anti-reflection effect thanks to the three-dimensional geometric configuration and the multiple scattering between individual nanostructures. These advantages potentially allow for high efficiency at a significantly reduced quantity and even at a reduced material quality, of the semiconductor material. In this article, several types of elongated nanostructures with the high potential to improve the device performance are reviewed. First, we briefly introduce the conventional solar cells with emphasis on thin film technology, following the most commonly used fabrication techniques for creating nanostructures with a high aspect ratio. Subsequently, several representative applications of elongated nanostructures, such as Si nanowires in realistic photovoltaic (PV) devices, are reviewed. Finally, the scientific challenges and an outlook for nanostructured PV devices are presented.

Kuang, Yinghuan; Di Vece, Marcel; Rath, Jatindra K.; van Dijk, Lourens; Schropp, Ruud E. I.

2013-10-01

324

aC:H absorber layer for solar cells matched to solar spectrum  

Microsoft Academic Search

An a-C:H-based absorber layer for photovoltaic application was fabricated by a DC PECVD. The stepped voltage biasing of the deposition process makes it possible to tailor the bandgap of the manufactured layers and match them to the solar spectrum. Such system can be used as intrinsic layer in p–i–n solar cells as well as in converter solar cells.

S. S. Tinchev; P. I. Nikolova; J. T. Dyulgerska; G. Danev; Tz. Babeva

2005-01-01

325

High-temperature solar cell for concentrated solar-power hybrid systems  

NASA Astrophysics Data System (ADS)

A high-temperature solar cell is proposed that harvests solar energy at elevated temperatures. Carrier separation is achieved by selective contacts that preferentially extract electrons or holes. The theoretical conversion efficiency of the proposed device is 38.6% at 600 K and an incident solar radiation concentration of 1000. The waste heat of this cell could be used by a secondary thermal converter boosting the total efficiency of the hybrid system above 55%.

Yang, Yang; Yang, Wenzheng; Tang, Weidong; Sun, Chuandong

2013-08-01

326

Thin-film cadmium telluride solar cells  

NASA Astrophysics Data System (ADS)

This is the final technical progress report of a research program entitled Thin-Film Cadmium Telluride Solar Cells. The major objective was to demonstrate chemical vapor deposition (CVD)-grown CdTe devices with a photovoltaic efficiency of at least 10%. The work included: (1) CVD and characterization of p-CdTe films of controlled resistivity; (2) deposition and characterization of heterojunction partners; (3) surface passivation of CdTe; and (4) preparation and characterization of thin-film solar cells. The CVD of p-CdTe was optimized with emphasis on resistivity control through nonstoichiometry and extrinsic doping. Both carbon and oxygen were identified as acceptors. The use of thermal oxidation for surface passivation of CdTe was investigated using capacitance-voltage measurement. Device-quality thermal oxide can be prepared by hydrogen annealing of CdTe before oxidation. Deposition and characterization of CdS, CdO, and ZnO:In were also carried out. The best thin-film cell to date had a conversion efficiency near 9%.

1986-09-01

327

Three neutrino oscillations applied to solar and long baseline experiments  

NASA Astrophysics Data System (ADS)

Details of the Standard Solar model and experiments measuring neutrinos produced inside the sun and in the upper atmosphere are reviewed. Inconsistencies between theoretical calculations and experimental measurements are discussed, establishing the need for new physics beyond the Standard model of Particle Physics. Neutrino oscillations are introduced as a viable solution and the phenomenology in the two flavour case is reviewed. Calculations of neutrino oscillations at long baseline experiments are performed using realistic spectra and source/detector combinations. Both vacuum and matter enhanced oscillations of solar neutrinos are computed to account for the solar neutrino data, and allowed regions of parameter space are found. New analytical results are presented which determine the three family hamiltonian in matter. Oscillation probabilities in vacuum are calculated, and methods to account for matter effects are outlined. A numerical treatment to determine the CKM parameters in matter is shown to be identical to existing analytical results in the literature. Computer codes developed to calculate long baseline neutrino oscillation experiments through the earth's variable density are discussed. Several techniques used in a second set of programs written to determine solar neutrino survival probabilities in the three neutrino case are also reviewed. Symmetries between four different mass hierarchies which have two well-separated mass scales are studied. A two- fold degeneracy noted in the literature is shown to be inherent in experiments which only measure muon neutrino oscillations, and an expression relating the two sets of CKM parameters is calculated. Detailed computations illustrate how long baseline experiments can determine the CKM parameters. First order matter effects are included and numerical work shows where matter effects are likely to break some of the symmetries. The phenomenon of CP violation in both vacuum and matter is studied in the three neutrino scenario. Existing work on first order matter and CP corrections to oscillation probabilities at long baseline experiments is extended to second order. It is argued that since CP effects are very likely to be smaller than matter, second order corrections are necessary. In detailed calculations, second order effects are clearly apparent. At high energies the approximation breaks down, but numerical results yield accurate answers allowing further study. Several strategies to isolate CP violation from competing matter effects are suggested, including tuning the neutrino beam energy and a novel approach which combines data sets from accelerator and reactor based experiments. Finally, new analytical work is presented showing that CP violation may modify the ratio of ?-type to e-type neutrinos in the atmospheric flux. The magnitude of the effect is estimated and found to be significant. New techniques allow solar neutrino survival probabilities to be calculated including three mixing angles and two mass scales. A preliminary survey is performed assuming one relevant mass scale but including the three angular parameters. A distinct three neutrino solution is found by allowing the large neutrino mass squared difference to drop somewhat below the atmospheric neutrino data's best fit solution of 3×10-4 eV2. Then the high energy tail of the 8B neutrino flux is converted to ?? by a second resonance in the sun, leaving unique spectral characteristics to differentiate it from two neutrino models.

Hayward, Scott Kelly

1998-11-01

328

Computer modeling of high intensity solar cells  

NASA Astrophysics Data System (ADS)

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 achieving the predicted theoretical efficiencies (in excess of 30% at concentration) are examined. It is demonstrated, by two-dimensional computer simulations, that these efficiencies might be obtained by improved light trapping techniques and by fabrication of low resistance heteroface contacts. The second paper examines the Rose-Weaver lifetime and surface recombination velocity measurement technique. It is shown that the very small uncertainties in the measured quantities lead to large uncertainties in the computed lifetime and surface recombination velocity. This leads to radically different interpretations of how the recombination is distributed throughout the device, and therefore limits the usefulness of the measurement technique. Design options and constraints of GaAs concentrator cells are examined in the third paper. The effectiveness of various design options is assessed. It is shown that although such design options are of little use in increasing the efficiency of heteroface cells, they can improve the efficiency of shallow junction cells so that it is comparable to that of heteroface cells, In addition, documentation describing the use of both the one- and two-dimensional silicon codes, SCAP1D and SCAP2D, as well as the one-dimensional AlGaAs solar cell simulation code is included.

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

1987-01-01

329

Optimization of n–i–p protocrystalline SiGe:H thin film solar cells for application in thin film multijunction solar cells  

Microsoft Academic Search

In developing n–i–p structured narrow band gap protocrystalline SiGe:H thin film solar cells, an S-shape was encountered in the cells’ current–voltage characteristics, which was not present in the curves of p–i–n cells that incorporated the same i-layer material. With the help of a carefully designed series of annealing experiments, the S-shape was found to consist of two barriers, one of

H. Li; R. L. Stolk; R. H. Franken; J. K. Rath; R. E. I. Schropp

2006-01-01

330

Cable interconnections for solar cell modules  

SciTech Connect

This patent describes a photovoltaic solar cell device having a rear wall and a conductive terminal strip protruding from the rear wall and having a hole therein, a member made of an insulating material secured to the rear wall, the member having an aperture and being positioned so that the hole in the terminal strip extends across the aperture, and a nut capturing the strip to the member so as to provide an electrical connection with the strip, the nut having a threaded hole accessible through the aperture to receive a threaded hole accessible through the aperture to receive a threaded fastener for securing the strip to an electrical cable.

Tronstrom, E.; Norbedo, A.J.

1992-05-05

331

Heteroepitaxially grown InP solar cells  

Microsoft Academic Search

The properties of InP solar cells, processed by OMCVD on silicon substrates with an intermediate GaAs layer (InP\\/GaAs\\/Si) and on GaAs substrates (InP\\/GaAs), were determined before and after irradiation with 10-MeV protons. The preirradiation transport properties were found to be influenced largely by dislocations occurring at the InP-GaAs interface. A carrier removal rate of 1.8×103 cm-1 was observed after irradiation

I. Weinberg; C. K. Swartz; D. J. Brinker; D. M. Wilt

1990-01-01

332

Dye for dye-sensitized solar cell and dye-sensitized solar cell including the same  

US Patent & Trademark Office Database

A dye for a dye-sensitized solar cell according to embodiments of the present invention includes a compound having a silane group. The dye according to embodiments of the present invention may be used in a light absorption layer to improve photovoltaic efficiency and increase open-circuit voltage.

2011-08-02

333

Solar energy from spinach and toothpaste: fabrication of a solar cell in schools  

NASA Astrophysics Data System (ADS)

We will show how pupils can make a solar cell with spinach, toothpaste and a few other items found in any school laboratory. This device is called a Graetzel cell, and could trigger off a revolution in photovoltaic technology.

Siemsen, F.; Bunk, A.; Fischer, K.; Korneck, F.; Engel, H.; Roux, D.

1998-01-01

334

Significant Reduction in Arc Frequency Biased Solar Cells: Observations, Diagnostics, and Mitigation Technique(S).  

National Technical Information Service (NTIS)

A variety of experiments were performed which identify key factors contributing to the arcing of negatively biased high voltage solar cells. These efforts have led to reduction of greater than a factor of 100 in the arc frequency of a single cell followin...

B. L. Upschulte G. M. Weyl W. J. Marinelli E. Aifer D. Hastings

1991-01-01

335

Natural convection in passive solar buildings: experiments, analysis, and results  

SciTech Connect

Computer programs have been developed to simulate numerically natural convection in two- and three-dimensional room geometries. The programs have been validated using published data from the literature, results from a full-scale experiment performed at the Massachusetts Institute of Technology, and results from a small-scale experiment performed at LBL. One of the computer programs has been used to study the influence of natural convection on the thermal performance of a single zone in a direct-gain passive solar building. It is found that the convection heat transfer coefficients between the air and the enclosure surfaces can be substantially different from the values assumed in the standard building energy analysis methods, and can exhibit significant variations across a given surface. This study implies that the building heating loads calculated by standard building energy analysis methods may have substantial errors as a result of their use of common assumptions regarding the convection processes which occur in an enclosure.

Gadgil, A.; Bauman, F.; Kammerud, R.

1982-01-01

336

Solar cell calibration facility validation of balloon flight data: a comparison of shuttle and balloon flight results  

SciTech Connect

The Solar Cell Calibration Facility (SCCF) experiment was designed and built to evaluate the effect of the Earth's upper atmosphere on the calibration of solar cell standards. During execution of the experiment, a collection of carefully selected solar cells was flown on the shuttle, and reflown on a high-altitude balloon, then their outputs were compared. After correction to standard temperature and intensity values of 28 C and an Earth-Sun distance of 1 AU, the solar cell outputs during the two flights were found to be identical. The conclusion is therefore that the high-altitude balloon flights are very good vehicles for calibrating solar cells for use as space flight reference standards.

Anspaugh, B.E.; Downing, R.G.; Sidwell, L.B.

1985-10-01

337

Flexible solar cells based on cadmium sulfide and telluride  

SciTech Connect

Output parameters and diode characteristics under illumination of flexible thin-film solar cells ITO/CdS/CdTe/Cu/Au formed on polyimide films by vacuum methods are studied. Using mathematical modeling of the effect of diode characteristics under illumination on the efficiency, the physicothechnical parameters of such structures are optimized. This made it possible to obtain laboratory samples of flexible solar cells based on cadmium sulfide and telluride with an efficiency of 11.4%. Solar modules with an efficiency of 4.5% based on the developed flexible solar cells are formed for the first time.

Khrypunov, G. S., E-mail: khrip@ukr.net; Chernykh, E. P.; Kovtun, N. A. [National Technical University 'Kharkov Polytehcnical Institute' (Ukraine); Belonogov, E. K. [Voronezh State Technical University (Russian Federation)], E-mail: belonogov@phys.vorstu

2009-08-15

338

Energy converting material for solar cell application  

NASA Astrophysics Data System (ADS)

In this paper, we discuss the concept of an efficient infrared upconverting phosphor as an energy converting material that could potentially improve the efficiency of Si solar cells in bifacial configuration. Basic spectroscopic studies of Yb and Er-doped La2O2S phosphor was reported with particular attention to its upconversion properties under 1550 nm excitation. Different concentrations of phosphors were synthesized by solid state flux fusion method. The phosphor powders were well crystallized in a hexagonal shape with an average size 300-400 nm. The most efficient upconverting sample (1%Yb: 9% Er doped La2O2S) was also studied under the illumination with infrared (IR) broad band spectrum above 1000 nm. Our measurements show that even with an excitation power density of 0.159 W/cm2 using a tungsten halogen lamp the material shows efficient upconversion corroborating the fact that the present phosphors could be potential candidates for improving the efficiency of the present Si solar cells.

Pokhrel, Madhab; Kumar, G. A.; Sardar, Dhiraj K.

2012-02-01

339

Device modeling for organic solar cells  

NASA Astrophysics Data System (ADS)

Organic solar cells (OSCs) are expected to play an important role in addressing our future energy needs due to their low cost and low processing requirements compared to inorganic solar cells (ISCs). However the efficiency of OSCs is still too low in comparison with ISCs for widespread applications. The biggest loss of quantum efficiency (QE) in OSCs is due to the limited free carrier generation occurring at the donor-acceptor (D-A) interface. Excitons (bound electron-hole pairs) are generated in the bulk by photo-absorption, but only a portion of them reach the D-A interface where they can dissociate into free charge carriers. Therefore, better understanding and control of exciton diffusion, free carrier generation and recombination are critical in order to improve QE for OSCs. To elucidate the physics of OSCs and aid in experimental studies, we developed a drift-diffusion model to describe the dynamics of excitons and free charge carriers. Our model predicts the performance of OSC devices by calculating their QE and current-voltage curves (I-V), as well as many other important physical quantities, such as the internal electric field, and the concentration and flux of excitons and free carriers. The effect of exciton and free carrier mobility, device temperature, and layer thickness, will be discussed. Furthermore, the exciton dissociation mechanism widely described by Onsager's model, will be investigated in detail.

Huang, Lunmei; Krasny, Robert; Renshaw, Kyle; Forrest, Stephen

2012-02-01

340

Layer Transferred Graphene for Solar Cell Applications  

NASA Astrophysics Data System (ADS)

Indium tin oxide (ITO) used commonly as a transparent electrode has proven to be unfavorable for the eventual commercialization of organic photovoltaic devices. We have investigated graphene grown on copper by CVD and transferred to arbitrary substrates as a possible replacement for ITO. Graphene-covered copper foils (Alfa Aesar) were first coated in photoresist (Shipley 1805) and the copper was removed with a ferric chloride based etchant. After cleaning in water the photoresist and graphene was transferred to the substrate of choice and the photoresist was removed with acetone. The transferred graphene were found to show a Hall mobility higher than 2000 cm^2/Vs at room temperatures and optical absorbance of 3.2% at 550nm and 2.5% at 900nm. We used scanning Raman spectroscopy to characterize the thickness of the graphene and found that 90+% of layer transferred material is single layer graphene. The remainder was found to consist of clusters of bi- or multi-layer graphene of a typical size ranging from 0.5 to 2 ?m. We fabricated organic hybrid solar cells utilizing this material as a transparent electrode. Results including a comparison between graphene and ITO devices fabricated using the same procedure and efforts to improve the efficiency of such graphene hybrid solar cells will be presented. Work supported in part by NSF.

Myers, Ronald; Wang, Zhibing; Liu, Ying; Robinson, Joshua; Todd, Aaron; Xu, Jian

2010-03-01

341

Novel solar cells in a wire format.  

PubMed

Photovoltaic devices in a wire format have recently attracted increasing attention as, compared with the conventional planar structure, they show unique and promising advantages. For instance, they are light-weight and can be easily woven into clothes or integrated into other structures, which enable applications in electronic textiles and various complex devices. In this tutorial review, the recent advancement in photovoltaic wires including both dye-sensitized and polymer solar cells are described. Two main architectures based on a single core-sheath fiber and twisted fibers are carefully illustrated with an emphasis on the comparison of various substrates which have been focused in past development. The current challenge including low energy conversion efficiency and low stability and future direction of the wire-shaped cell have been finally summarized. PMID:23467786

Chen, Tao; Qiu, Longbin; Yang, Zhibin; Peng, Huisheng

2013-06-21

342

Photoelectrochemical Cell With Nondissolving Anode: New cell may be an economical alternative to silicon solar cell.  

National Technical Information Service (NTIS)

This citation summarizes a one-page announcement of technology available for utilization. An improved electrolytic photovoltaic cell converts solar energy to electricity without electrode decomposition. Cell efficiencies up to 15 percent have been measure...

1982-01-01

343

Recent Progress in Inorganic Solar Cells Using Quantum Structures  

Microsoft Academic Search

Thermalization of photogenerated carriers in bulk materials is the main bottleneck for the conversion efficiency of conventional inorganic solar cells. Furthermore, despite extensive research, the achieved conversion efficiency is nearly saturated during the last decade. Therefore, new device concepts to break through the efficiency barrier are highly requested. Nanotechnologies are the building blocks for next-generation solar cells, because low-dimensional quantum

Seung Y. Myong

2007-01-01

344

An investigation of mismatch losses in solar photovoltaic cell networks  

Microsoft Academic Search

Solar photovoltaic (PV) arrays in field conditions deliver lower power than the array rating. In this paper, the sensitivity of solar cell parameters in the variation of available power from the array is investigated. The parameters characteristic of aging and fresh cells used in prototype field systems have been used for computation of reduction in the available power. It is

N. D. Kaushika; Anil K. Rai

2007-01-01

345

Development of Novel II-VI Solar Cells.  

National Technical Information Service (NTIS)

The epitaxial growth of novel II-VI solar cell structures was investigated. In Phase I, the metal organic chemical vapor deposition (MOCVD) process parameters and associated growth chemistries for an epitaxial p-i-n, ZnTe/CdTe/GaAs, solar cell structure w...

G. S. Tompa

1990-01-01

346

Review 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

347

Mercury cadmium telluride solar cell with 10. 6% efficiency  

SciTech Connect

Cd-rich mercury cadmium telluride (MCT) is a promising material for thin-film solar cell applications. In this letter we present data on the deposition of MCT films by a simple electroplating technique and report on the highest efficiency polycrystalline MCT thin-film solar cell to date, which has an efficiency of 10.6% under AM1.5 illumination.

Basol, B.M.; Tseng, E.S.

1986-04-07

348

CRADA Final Report: Process development for hybrid solar cells  

SciTech Connect

TCF funding of a CRADA between LBNL and RSLE leveraged RSLE's original $1M investment in LBNL research and led to development of a solar cell fabrication process that will bring the high efficiency, high voltage hybrid tandem solar cell closer to commercialization. RSLE has already built a pilot line at its Phoenix, Arizona site.

Ager, Joel W

2011-02-14

349

Electrical and optical characteristics of silicon nanocrystal solar cells  

Microsoft Academic Search

We investigated the relationship between the absorption in silicon nanocrystals (Si NCs) and the photocurrent of Si NC solar cells. Here, the absorption of Si NCs in the blue and green light regions was enhanced by up to 14 times compared to bulk Si. In addition, the photocurrent in Si NC solar cells was found to originate from absorption in

Sang-Kyun Kim; Chang-Hee Cho; Baek-Hyun Kim; Seong-Ju Park; Jae Won Lee

2009-01-01

350

Simulation studies on heterojunction and HIT solar cells  

NASA Astrophysics Data System (ADS)

Heterojunction solar cells have shown a promising comparable efficiency with the advantage of lower fabrication cost compared to the crystalline solar cells. In this paper, an attempt has been made to simulate the heterojunction structure and HIT structure using AMPS-1D software by applying various approaches. The simulation parameters of these structures are varied for cell efficiency, quantum efficiency, charge carrier concentration and temperature stability to achieve higher efficiency. The final solar cell parameters have been achieved about 20% for heterojunction and 23% for HIT cells. The effects on intrinsic and extrinsic characteristics of doped layers are discussed for these efficiencies.

Patel, Kamlesh; Panwar, O. S.; Bisht, Atul; Sreekumar, C.; Kumar, Sushil; Rauthan, C. M. S.

2012-10-01

351

Marketing solar thermal technologies: strategies in Europe, experience in Greece  

Microsoft Academic Search

Solar thermal technologies (STTs) are mature in many EU Member States. However, in some EU regions solar applications, and especially the innovative ones (such as solar heating\\/cooling, solar drying, solar-powered desalination), remain at an early stage. The degree of development of each market does not depend on climate conditions (e.g., insolation) or on different technological developments. The major strengths, weaknesses,

Theocharis D Tsoutsos

2002-01-01

352

Interim Report on Interdigitated Back-Contact Solar Cells.  

National Technical Information Service (NTIS)

The purpose of the work reported is to design, fabricate, test, and deliver silicon interdigitated back contact solar cells designed to operate at high sunlight intensity. A brief description of the Interdigitated Back Contact (IBC) cell is presented and ...

R. J. Schwartz

1978-01-01

353

How Porosity Modifies the Photovoltaic Effect in Nanocrystalline Solar Cells  

SciTech Connect

The porosity of the nanocrystalline semiconductor affects many aspects of the photoconversion process in dye-sensitzed solar cells, thus distinguishing them mechanistically from conventional photovoltaic and photoelectro-chemical cells. We discuss several examples from our recent work.

Gregg, B. A.; Pichot, F.

2000-01-01

354

Exploiting Nanocarbons in Dye-Sensitized Solar Cells.  

PubMed

Fullerenes, carbon nanotubes, nanodiamond, and graphene find various applications in the development of solar cells, including dye sensitized solar cells. Nanocarbons can be used as (1) active light-absorbing component, (2) current collector, (3) photoanode additive, or (4) counter electrode. Graphene-based materials have attracted considerable interest for catalytic counter electrodes, particularly in state-of-the-art dye sensitized solar cells with Co-mediators. The understanding of electrochemical charge-transfer at carbon surfaces is key to optimization of these solar cells, but the electrocatalysis on carbon surfaces is still a subject of conflicting debate. Due to the rich palette of problems at the interface of nanocarbons and photovoltaics, this review is selective rather than comprehensive. Its motivation was to highlight selected prospective inputs from nanocarbon science towards the development of novel dye sensitized solar cells with improved efficiency, durability, and cost. PMID:23729170

Kavan, Ladislav

2013-06-01

355

Near-Field Electromagnetic Theory for Thin Solar Cells  

NASA Astrophysics Data System (ADS)

Current methods for evaluating solar cell efficiencies cannot be applied to low-dimensional structures where phenomena from the realm of near-field optics prevail. We present a theoretical approach to analyze solar cell performance by allowing rigorous electromagnetic calculations of the emission rate using the fluctuation-dissipation theorem. Our approach shows the direct quantification of the voltage, current, and efficiency of low-dimensional solar cells. This approach is demonstrated by calculating the voltage and the efficiency of a GaAs slab solar cell for thicknesses from several microns down to a few nanometers. This example highlights the ability of the proposed approach to capture the role of optical near-field effects in solar cell performance.

Niv, A.; Gharghi, M.; Gladden, C.; Miller, O. D.; Zhang, X.

2012-09-01

356

Plastic solar cells: breaking the 10% commercialization barrier  

NASA Astrophysics Data System (ADS)

Tandem solar cells provide an effective way to harvest a broader spectrum of solar radiation by combining two or more solar cells with different absorption ranges. However, for polymer solar cells (PSCs), the performance of tandem devices lags behind single-layer cells mainly due to the lack of a high-performance low-bandgap polymer with appropriate spectral response range. Here, we demonstrate a novel low bandgap conjugated polymer (~1.44 eV) specifically suitable for tandem structure. In the single-layer device, power conversion efficiency (PCE) of 6.5% was achieved. When the polymer was applied to tandem solar cells, we demonstrated a NREL certified PCE of 8.62%[1] . Further optimization on materials and devices of this system has lead to record breaking efficiency of 10.6%. Furthermore, the tandem devices show excellent stability due both to the intrinsic stability of the polymer and the advanced device structure.

Dou, Letian; You, Jingbi; Chen, Chun-Chao; Li, Gang; Yang, Yang

2012-09-01

357

A Didactic Experiment and Model of a Flat-Plate Solar Collector  

ERIC Educational Resources Information Center

We report on an experiment performed with a home-made flat-plate solar collector, carried out together with high-school students. To explain the experimental results, we propose a model that describes the heating process of the solar collector. The model accounts quantitatively for the experimental data. We suggest that solar-energy topics should…

Gallitto, Aurelio Agliolo; Fiordilino, Emilio

2011-01-01

358

A Didactic Experiment and Model of a Flat-Plate Solar Collector  

ERIC Educational Resources Information Center

|We report on an experiment performed with a home-made flat-plate solar collector, carried out together with high-school students. To explain the experimental results, we propose a model that describes the heating process of the solar collector. The model accounts quantitatively for the experimental data. We suggest that solar-energy topics should…

Gallitto, Aurelio Agliolo; Fiordilino, Emilio

2011-01-01

359

Photon-degradation effects in terrestrial silicon solar cells  

Microsoft Academic Search

An unexplained instability in terrestrial solar-cell output under various use conditions has been observed. The effect is similar to but not identical with previously observed photon-induced degradation phenomenon in radiation-damaged space solar cells. Reduction in cell output is observed in n+\\/p cells upon exposure to illumination or upon the application of a sufficiently high forward bias. Conversely, an enhancement in

V. G. Weizer; H. W. Brandhorst; J. D. Broder; R. E. Hart; J. H. Lamneck

1979-01-01

360

Effective diffusion length of multicrystalline solar cells  

NASA Astrophysics Data System (ADS)

Previous definitions of effective diffusion length 0268-1242/13/7/021/img1 of a multicrystalline semiconductor are reviewed. A new definition is proposed, which is based on the comparison of the current collected from the base of a multicrystalline solar cell and a single-crystal cell for uniform carrier generation, and holds for any sample thickness. An analytical expression for 0268-1242/13/7/021/img1 is obtained from the solution of the three-dimensional equation for the charge collection probability 0268-1242/13/7/021/img3 inside a grain with square cross section. This expression is used to numerically study the dependence of 0268-1242/13/7/021/img1 on the bulk diffusion length, grain size and grain boundary recombination velocity, and to make a comparison with previous specifications of 0268-1242/13/7/021/img1. The results indicate, in particular, that 0268-1242/13/7/021/img1 is the value that would be determined by the surface photovoltage method. The case of a cell with grains of different properties is briefly discussed and an average 0268-1242/13/7/021/img1 is defined. It is also shown that 0268-1242/13/7/021/img3 can be used to calculate the contribution of the base to the reverse saturation current of the cell.

Donolato, C.

1998-07-01

361

AlGaAs Top Solar Cell for Mechanical Attachment in a Multi-Junction Tandem Concentrator Solar Cell Stack.  

National Technical Information Service (NTIS)

The AstroPower self-supporting, transparent AlGaAs top solar cell can be stacked upon any well-developed bottom solar cell for improved system performance. This is an approach to improve the performance and scale of space photovoltaic power systems. Mecha...

L. C. Dinetta M. H. Hannon J. B. Mcneely A. M. Barnett

1991-01-01

362

Nanoparticle distribution in polymer solar cells  

NASA Astrophysics Data System (ADS)

Polymer based solar cells (PSC) hold the promise of cheap, versatile devices for harnessing solar energy. A widely studied PSC is poly-3-hexylthiophene (P3HT) blended with [6,6] - phenyl-C61 - butyric acid methyl ester (PCBM) nanoparticles. The acceptor PCBM is needed to inhibit exciton recombination, thus, proper PCBM distribution is critical for photovoltaic performance. However, determining this distribution is challenging, as PCBM is extremely difficult to distinguish from P3HT via standard techniques like microscopy or x-ray diffraction. Neutron scattering presents a solution, as the scattering potential for PCBM is ˜5 x that of P3HT. Thus, we have studied PCBM:P3HT thin film samples using neutron reflectometry, which is sensitive to the compositional depth profile.[1] Measurements were conducted both with a weak scatterer (air) and then with a strong scatterer (D2O) backing the sample, such that the depth profile could be calculated from the reflectometry data with no fitting parameters, and/or model fitted with virtually no ambiguity. We find that PCBM aggregates near the substrate and surface interfaces of the P3HT film, implying that the PCBM is not optimally distributed for best photovoltaic performance. In general, this work demonstrates the extreme utility of neutron reflectometry for studying this class of materials. [1] Kiel, et al. Soft Matter, DOI:10.1039/B920979D (2009).

Kirby, B. J.; Kiel, J. W.; Maranville, B. B.; Majkrzak, C. F.; Mackay, M. E.

2010-03-01

363

Photovoltaic technology: the case for thin-film solar cells  

PubMed

The advantages and limitations of photovoltaic solar modules for energy generation are reviewed with their operation principles and physical efficiency limits. Although the main materials currently used or investigated and the associated fabrication technologies are individually described, emphasis is on silicon-based solar cells. Wafer-based crystalline silicon solar modules dominate in terms of production, but amorphous silicon solar cells have the potential to undercut costs owing, for example, to the roll-to-roll production possibilities for modules. Recent developments suggest that thin-film crystalline silicon (especially microcrystalline silicon) is becoming a prime candidate for future photovoltaics. PMID:10426984

Shah; Torres; Tscharner; Wyrsch; Keppner

1999-07-30

364

Basic experiment on charging mitigation of solar array in geostationary orbit environment  

Microsoft Academic Search

Many of spacecraft anomalies are caused by discharge on solar array. We investigate two methods to mitigate discharge on the solar array of spacecraft in geostationary orbit (GEO). The first method is to have discharge at safer points before the discharge occurs on solar cells. The second method is not to make the potential of the spacecraft negative. The mitigation

Y. Sanmaru; T. Ose; T. Kawasaki; Y. Sikata; S. Hosoda; M. Iwata; K. Toyoda; Mengu Cho; T. Fujita

2006-01-01

365

Solar cells incorporating light harvesting arrays  

DOEpatents

A solar cell incorporates a light harvesting array that comprises: (a) a first substrate comprising a first electrode; and (b) a layer of light harvesting rods electrically coupled to the first electrode, each of the light harvesting rods comprising a polymer of Formula I: X.sup.1.paren open-st.X.sup.m+1).sub.m (I) wherein m is at least 1, and may be from two, three or four to 20 or more; X.sup.1 is a charge separation group (and preferably a porphyrinic macrocycle, which may be one ligand of a double-decker sandwich compound) having an excited-state of energy equal to or lower than that of X.sup.2 ; and X.sup.2 through X.sup.m+1 are chromophores (and again are preferably porphyrinic macrocycles).

Lindsey, Jonathan S. (Raleigh, NC); Meyer, Gerald J. (Baltimore, MD)

2002-01-01

366

Core-shell silicon nanowire solar cells  

PubMed Central

Silicon nanowires can enhance broadband optical absorption and reduce radial carrier collection distances in solar cell devices. Arrays of disordered nanowires grown by vapor-liquid-solid method are attractive because they can be grown on low-cost substrates such as glass, and are large area compatible. Here, we experimentally demonstrate that an array of disordered silicon nanowires surrounded by a thin transparent conductive oxide has both low diffuse and specular reflection with total values as low as < 4% over a broad wavelength range of 400?nm < ? < 650?nm. These anti-reflective properties together with enhanced infrared absorption in the core-shell nanowire facilitates enhancement in external quantum efficiency using two different active shell materials: amorphous silicon and nanocrystalline silicon. As a result, the core-shell nanowire device exhibits a short-circuit current enhancement of 15% with an amorphous Si shell and 26% with a nanocrystalline Si shell compared to their corresponding planar devices.

Adachi, M. M.; Anantram, M. P.; Karim, K. S.

2013-01-01

367

Hot exciton dissociation in polymer solar cells  

NASA Astrophysics Data System (ADS)

The standard picture of photovoltaic conversion in all-organic bulk heterojunction solar cells predicts that the initial excitation dissociates at the donor/acceptor interface after thermalization. Accordingly, on above-gap excitation, the excess photon energy is quickly lost by internal dissipation. Here we directly target the interfacial physics of an efficient low-bandgap polymer/PC60BM system. Exciton splitting occurs within the first 50?fs, creating both interfacial charge transfer states (CTSs) and polaron species. On high-energy excitation, higher-lying singlet states convert into hot interfacial CTSs that effectively contribute to free-polaron generation. We rationalize these findings in terms of a higher degree of delocalization of the hot CTSs with respect to the relaxed ones, which enhances the probability of charge dissociation in the first 200?fs. Thus, the hot CTS dissociation produces an overall increase in the charge generation yield.

Grancini, G.; Maiuri, M.; Fazzi, D.; Petrozza, A.; Egelhaaf, H.-J.; Brida, D.; Cerullo, G.; Lanzani, G.

2013-01-01

368

Efficiency of silicon solar cells containing chromium  

DOEpatents

Efficiency of silicon solar cells containing about 10.sup.15 atoms/cm.sup.3 of chromium is improved about 26% by thermal annealing of the silicon wafer at a temperature of 200.degree. C. to form chromium precipitates having a diameter of less than 1 Angstrom. Further improvement in efficiency is achieved by scribing laser lines onto the back surface of the wafer at a spacing of at least 0.5 mm and at a depth of less than 13 micrometers to preferentially precipitate chromium near the back surface and away from the junction region of the device. This provides an economical way to improve the deleterious effects of chromium, one of the impurities present in metallurgical grade silicon material.

Frosch, Robert A. Administrator of the National Aeronautics and Space (New Port Beach, CA); Salama, Amal M. (New Port Beach, CA)

1982-01-01

369

Semitransparent organic solar cells with organic wavelength dependent reflectors  

NASA Astrophysics Data System (ADS)

Semitransparent organic solar cells employing solution-processable organic wavelength dependent reflectors of chiral nematic (cholesteric) liquid crystals are demonstrated. The cholesteric liquid crystal (CLC) reflects only in a narrow band of the solar spectrum and remains transparent for the remaining wavelengths. The reflective band is matched to the absorption spectrum of the organic solar cell such that only unabsorbed photons that can contribute to the photocurrent are reflected to pass through the active layer a second time. In this way, the efficiency of semitransparent organic solar cells can be enhanced without significant transparency losses. An efficiency increase of 6% was observed when a CLC reflector with a reflection band of 540-620 nm was used, whereas the transparency of the organic solar cells is only suppressed in the 80 nm narrow bandwidth.

Galagan, Yulia; Debije, Michael G.; Blom, Paul W. M.

2011-01-01

370

UV spectrum and proposed role of diethylberyllium in a Li-7-Be-7 solar neutrino experiment  

NASA Astrophysics Data System (ADS)

Although measurement of the solar neutrino flux via the Li-7(nu sub e, e(-))B-7 reaction was proposed many years ago, no experiment has been implemented since it has been difficult to identify a sensitive Be-7 detection technique. Here it is proposed that the Be-7 atom be incorporated into a volatile molecule, placed in a buffer-gas-filled cell, and then extracted by photodissociation; after excitation by a tunable laser, bursts of photons would be detected. The absorption spectrum of the molecular candidate diethylberyllium has been measured between 186 and 270 nm in a spectrophotometer to determine the required photodissociation laser wavelength and intensity.

Dyer, P.

1992-05-01

371

UV Spectrum and Proposed Role of Diethylberyllium in a 7Li-7Be Solar Neutrino Experiment.  

PubMed

Although measurement of the solar neutrino flux via the (7)Li(v(e),e(-))(7)Be reaction was proposed many years ago, no experiment has been implemented since it has been difficult to identify a sensitive (7)Be detection technique. Here it is proposed that the (7)Be atom be incorporated into a volatile molecule, placed in a buffer-gas-filled cell, and then extracted by photodissociation; after excitation by a tunable laser, bursts of photons would be detected. The absorption spectrum of the molecular candidate diethylberyllium has been measured between 186 and 270 nanometers in a spectrophotometer to determine the required photodissociation laser wavelength and intensity. PMID:17756445

Dyer, P

1992-05-01

372

Area-scaling of organic solar cells  

NASA Astrophysics Data System (ADS)

We report on the performance of organic solar cells based on pentacene/C60 heterojunctions as a function of active area. Devices with areas of 0.13 and 7 cm2 were fabricated on indium-tin-oxide (ITO) coated glass. Degradation of the performance with increased area is observed and analyzed in terms of the power loss density concept. The various power loss contributions to the total series resistance (RSA) are measured independently and compared to the values of the series resistance extracted from the current-voltage characteristics using a Shockley equivalent circuit model. The limited sheet resistance of ITO is found to be one of the major limiting factors when the area of the cell is increased. To reduce the effects of series resistance, thick, electroplated, metal grid electrodes were integrated with ITO in large-area cells. The metal grids were fabricated directly onto ITO and passivated with an insulator to prevent electrical shorts during the deposition of the top Al electrode. By integrating metal grids onto ITO, the series resistance could be reduced significantly yielding improved performance. Design guidelines for metal grids are described and tradeoffs are discussed.

Choi, Seungkeun; Potscavage, William J.; Kippelen, Bernard

2009-09-01

373

Surface Plasmon Enhancement of Organic Solar Cells  

NASA Astrophysics Data System (ADS)

Organic photovoltaic (OPV) devices are inherently less efficient than silicon based devices. The short electron diffusion lengths in OPVs require the cells to be kept thin, diminishing their light absorption. One way to increase the absorption of these devices is to launch surface plasmons (SPs) along one of the electrodes at specific wavelengths in the solar spectrum. SPs are coherent electron oscillations that exist at the surface of a metal-dielectric boundary, and serve to focus light at the metal surface. This increase in absorption ultimately impacts the overall efficiency of the device. The OPV cells are fabricated on top of glass slides and consist of an organic heterojunction active layer residing between ITO and aluminum electrodes. SP coupling is achieved by forming sinusoidal gratings of various periods along the active layer/Al electrode boundary. Efficiency measurements of patterned and unpatterned samples were taken to determine if the gratings have any effect on the cell efficiency at the predicted wavelengths. No significant changes in efficiency have been observed, which could be due to the abnormally low efficiencies of the devices that were tested.

Shope, David; Steele, Jennifer

2011-10-01

374

Enhancing Solar Cell Efficiencies through 1-D Nanostructures  

Microsoft Academic Search

The current global energy problem can be attributed to insufficient fossil fuel supplies and excessive greenhouse gas emissions\\u000a resulting from increasing fossil fuel consumption. The huge demand for clean energy potentially can be met by solar-to-electricity\\u000a conversions. The large-scale use of solar energy is not occurring due to the high cost and inadequate efficiencies of existing\\u000a solar cells. Nanostructured materials

Kehan Yu; Junhong Chen

2009-01-01

375

Solar Cell Energy Availability From Around the Country  

NSDL National Science Digital Library

Solar cells have varying amounts of effectiveness depending on factors such as latitude and cloud coverage. For example, locations with more cloud coverage will produce less solar energy. By comparing the monthly averages of surface downward radiation in various locations around the United States, students can analyze areas that would be more or less beneficial to having solar panels per month. This lesson will introduce students to difference plots and how they can analyze such information.

376

Apollo 11 Solar Wind Composition Experiment: First Results  

Microsoft Academic Search

The helium-4 solar wind flux during the Apollo 11 lunar surface excursion was (6.3 ± 1.2) × 106 atoms per square centimeter per second. The solar wind direction and energy are essentially not perturbed by the moon. Evidence for a lunar solar wind albedo was found.

F. Buehler; P. Eberhardt; J. Geiss; J. Meister; P. Signer

1969-01-01

377

High efficiency thin film cadmium telluride solar cells  

NASA Astrophysics Data System (ADS)

Cadmium sulfide (CdS), grown from an aqueous solution, and zinc oxide (ZnO), cadmium zinc sulfide (Cd1-xZnxS), and zinc selenide (ZnSe), deposited by metalorganic chemical vapor deposition (MOCVD), have been used as the window for thin film cadmium telluride (CdTe) solar cells. Thin film solar cells were prepared by the successive deposition of the window and p-CdTe (by MOCVD and close-spaced sublimation, CSS) on SnO2:F/glass substrates. CdS/CdTe(CSS) solar cells show considerably better characteristics than CdS/CdTe(MOCVD) solar cells because of the better microstructure of CSS CdTe films. Total area conversion efficiency of 14.6%, verified by the National Renewable Energy Laboratory, has been achieved for solar cells of about 1 cm2 area. Solar cell prepared by using ZnO, ZnSe, or Cd1-xZnxS as window have significantly lower photovoltage than CdS/CdTe solar cells.

Chu, T. L.; Chu, Shirley S.; Britt, J.; Chen, G.; Ferekides, C.; Schultz, N.; Wang, C.; Wu, C. Q.

1992-12-01

378

Simulation Experiments on Dust Aggregation in the Early Solar Nebula  

NASA Astrophysics Data System (ADS)

The evolution of dust particles in the early solar nebula is most probably determined by aggregation of micron-sized grains. With respect to different scenarios as Brownian motion, differential sedimentation, orbital decay and turbulence, relative velocities between different particles are generated which lead to subsequent collisions, sticking and growth. The aggregates evolve to certain structures which might be characterized by a fractal dimension d, relating the mass m of the clusters to its size s, m ~ s(d) . Computer simulations show that d is supposed to be close to 2. The value of d is important for the timescales of the formation of planetesimals. Parameters for the model calculations, such as sticking probabilities for different velocities and the ability of the particles for sliding and rolling on the surfaces during impacts are needed. We carried out collision experiments with aggregates consisting of up to a few hundred single micron-sized amorphous SiO_2 particles. The device generating these aggregates, an aggregation experiment of its own, produces clusters of the fractal dimension 1.9. In 'levitation tube' experiments, we observed collisions between single clusters due to differential sedimentation. The collision velocities ranged from 1 mm/s to 1 cm/s. All collisions resulted in sticking as predicted by theory. We found no significant restructuring within the limits of our optical system, a long distance microscope and flash lamp illumination. Images were taken by a digital CCD camera (256 * 256 pixels) with 150 frames per second. In another series of experiments under the microgravity conditions of the drop tower in Bremen as well as in the laboratory, we directed a beam of the above-mentioned clusters to a thin target and observed sticking and restructuring due to the impact and gravitational torques. We will present new results of these investigations.

Wurm, G.; Blum, J.

1996-09-01

379

Environmental (sup 222)Rn as a background source in the solar neutrino experiment GALLEX.  

National Technical Information Service (NTIS)

The radiochemical neutrino experiment GALLEX is described. Its aim is to measure the flux of low energy solar neutrinos. In this experiment it is essential to suppress strongly the background of environmental origin, like charged cosmic rays, neutrons and...

M. Wojcik

1996-01-01

380

Summary of engineering-scale experiments for the Solar Detoxification of Water project  

Microsoft Academic Search

This report contains a summary of large-scale experiments conducted at Sandia National Laboratories under the Solar Detoxification of Water project. The objectives of the work performed were to determine the potential of using solar radiation to destroy organic contaminants in water by photocatalysis and to develop the process and improve its performance. For these experiments, we used parabolic troughs to

J. E. Pacheco; L. Yellowhorse

1992-01-01

381

Experiments and analysis of the role of solar power in limiting Mars rover range  

Microsoft Academic Search

A common explanation for the limited distance traveled by NASA's past and planned Mars rovers is the limits of solar power. This paper explores this hypothesis and documents a series of experiments with a solar powered rover. A detailed comparison between our rover and Sojourner, with regards to power usage, is presented. Experiments and analysis clearly show that other factors

David P. Miller; Tim S. Hunt; Matt J. Roman

2003-01-01

382

Massless scalar field and solar-system experiments  

SciTech Connect

The solution of Einstein's field equations with the energy-momentum tensor of a massless scalar field is known as the Fisher solution. It is well known that this solution has a naked singularity due to the ''charge''{Sigma} of the massless scalar field. Here I obtain the radial null geodesic of the Fisher solution and use it to confirm that there is no black hole. In addition, I use the parametrized post-Newtonian formalism to show that the Fisher spacetime predicts the same effects on solar-system experiments as the Schwarzschild one does, as long as we impose a limit on {Sigma}. I show that this limit is not a strong constraint and we can even take values of {Sigma} bigger than M. By using the exact formula of the redshift and some assumptions, I evaluate this limit for the experiment of Pound and Snider [Phys. Rev. 140, B788 (1965)]. It turns out that this limit is {Sigma}<5.8x10{sup 3} m.

Formiga, J. B. [Departamento de Fisica, Universidade Federal da Paraiba, Caixa Postal 5008, 58051-970 Joao Pessoa, Paraiba (Brazil)

2011-04-15

383

Thin multi-junction solar cells of III-V materials to advance solar energy harvesting  

NASA Astrophysics Data System (ADS)

Significant advancements in photovoltaic solar cells are required to support large-scale energy demands with solar power. The first generation of solar cells (SC) available today uses Si. While Si is highly abundant and these types of SC can be easily manufactured, the best power conversion efficiency is only 24%. Developing photovoltaic SC using III-V materials may increase the efficiency while decreasing the manufacturing costs associated with cell fabrication. This paper studies the opportunity to improve two-junctions solar cells made of III-V materials by making the layers very thin and including the antireflective layer in the first junction. In terms of light harvesting, the anti-reflective layer made of a semiconductor is shown to absorb the most part of the incident light.

Castelletto, S.; Parker, A.

2013-09-01

384

Neural Network Modeling of Degradation of Solar Cells  

SciTech Connect

Neural network modeling has been used to predict the degradation in conversion efficiency of solar cells in this work. The model takes intensity of light, temperature and exposure time as inputs and predicts the conversion efficiency of the solar cell. Backpropagation algorithm has been used to train the network. It is found that the neural network model satisfactorily predicts the degradation in efficiency of the solar cell with exposure time. The error in the computed results, after comparison with experimental results, lies in the range of 0.005-0.01, which is quite low.

Gupta, Himanshu; Ghosh, Bahniman [Department of Electrical Engineering, Indian Institute of Technology, Kanpur, 208016 (India); Banerjee, Sanjay K. [Department of Electrical and Computer Engineering, University of Texas at Austin, Austin, TX, 78758 (United States)

2011-05-25

385

Accelerated aging of GaAs concentrator solar cells  

SciTech Connect

An accelerated aging study of AlGaAs/GaAs solar cells has been completed. The purpose of the study was to identify the possible degradation mechanisms of AlGaAs/GaAs solar cells in terrestrial applications. Thermal storage tests and accelerated AlGaAs corrosion studies were performed to provide an experimental basis for a statistical analysis of the estimated lifetime. Results of this study suggest that a properly designed and fabricated AlGaAs/GaAs solar cell can be mechanically rugged and environmentally stable with projected lifetimes exceeding 100 years.

Gregory, P.E.

1982-04-01

386

Crystalline silicon solar cells with micro/nano texture  

NASA Astrophysics Data System (ADS)

Crystalline silicon solar cells with two-scale texture consisting of random upright pyramids and surface nanotextured layer directly onto the pyramids are prepared and reflectance properties and I-V characteristics measured. Random pyramids texture is produced by etching in an alkaline solution. On top of the pyramids texture, a nanotexture is developed using an electroless oxidation/etching process. Solar cells with two-scale surface texturization are prepared following the standard screen-printing technology sequence. The micro/nano surface is found to lower considerably the light reflectance of silicon. The short wavelengths spectral response (blue response) improvement is observed in micro/nano textured solar cells compared to standard upright pyramids textured cells. An efficiency of 17.5% is measured for the best micro/nano textured c-Si solar cell. The efficiency improvement is found to be due to the gain in both Jsc and Voc.

Dimitrov, Dimitre Z.; Du, Chen-Hsun

2013-02-01

387

Solar Cell light trapping beyond the ray optic limit.  

PubMed

In 1982, Yablonovitch proposed a thermodynamic limit on light trapping within homogeneous semiconductor slabs, which implied a minimum thickness needed to fully absorb the solar spectrum. However, this limit is valid for geometrical optics but not for a new generation of subwavelength solar absorbers such as ultrathin or inhomogeneously structured cells, wire-based cells, photonic crystal-based cells, and plasmonic cells. Here we show that the key to exceeding the conventional ray optic or so-called ergodic light trapping limit is in designing an elevated local density of optical states (LDOS) for the absorber. Moreover, for any semiconductor we show that it is always possible to exceed the ray optic light trapping limit and use these principles to design a number of new solar absorbers with the key feature of having an elevated LDOS within the absorbing region of the device, opening new avenues for solar cell design and cost reduction. PMID:22149061

Callahan, Dennis M; Munday, Jeremy N; Atwater, Harry A

2012-01-03

388

Understanding junction breakdown in multicrystalline solar cells  

NASA Astrophysics Data System (ADS)

Extensive investigations on industrial multicrystalline silicon solar cells have shown that, for standard 1 ? cm material, acid-etched texturization, and in absence of strong ohmic shunts, there are three different types of breakdown appearing in different reverse bias ranges. Between -4 and -9 V there is early breakdown (type 1), which is due to Al contamination of the surface. Between -9 and -13 V defect-induced breakdown (type 2) dominates, which is due to metal-containing precipitates lying within recombination-active grain boundaries. Beyond -13 V we may find in addition avalanche breakdown (type 3) at etch pits, which is characterized by a steep slope of the I-V characteristic, avalanche carrier multiplication by impact ionization, and a negative temperature coefficient of the reverse current. If instead of acid-etching alkaline-etching is used, all these breakdown classes also appear, but their onset voltage is enlarged by several volts. Also for cells made from upgraded metallurgical grade material these classes can be distinguished. However, due to the higher net doping concentration of this material, their onset voltage is considerably reduced here.

Breitenstein, Otwin; Bauer, Jan; Bothe, Karsten; Kwapil, Wolfram; Lausch, Dominik; Rau, Uwe; Schmidt, Jan; Schneemann, Matthias; Schubert, Martin C.; Wagner, Jan-Martin; Warta, Wilhelm

2011-04-01

389

Solar Hydrogen Fuel Cell Projects at Brooklyn Tech  

ERIC Educational Resources Information Center

This article describes the projects on solar hydrogen powered vehicles using water as fuel conducted by teams at Brooklyn Technical High School. Their investigations into the pure and applied chemical thermodynamics of hydrogen fuel cells and bio-inspired devices have been consolidated in a new and emerging sub-discipline that they define as solar

Fedotov, Alex; Farah, Shadia; Farley, Daithi; Ghani, Naureen; Kuo, Emmy; Aponte, Cecielo; Abrescia, Leo; Kwan, Laiyee; Khan, Ussamah; Khizner, Felix; Yam, Anthony; Sakeeb, Khan; Grey, Daniel; Anika, Zarin; Issa, Fouad; Boussayoud, Chayama; Abdeldayem, Mahmoud; Zhang, Alvin; Chen, Kelin; Chan, Kameron Chuen; Roytman, Viktor; Yee, Michael

2010-01-01

390

Solar Cell and Array Standardization for Air Force Spacecraft.  

National Technical Information Service (NTIS)

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 c...

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

1974-01-01

391

Natural and simulated hypervelocity impacts into solar cells  

Microsoft Academic Search

The solar array which was returned to Earth from the Hubble Space Telescope (HST) in 1993, after 3.62 years of space exposure in low Earth orbit (LEO), has offered the opportunity to document populations of natural micrometeoroids and artificial “space debris”. Residues from the hypervelocity impact (HVI) of material deposited in 25 individual solar cells from the array have been

G. A. Graham; A. T. Kearsley; M. M. Grady; I. P. Wright; M. K. Herbert; J. A. M. McDonnell

1999-01-01

392

Nanostructured photovoltaic devices for next generation solar cell  

Microsoft Academic Search

As the search for alternative sources of energy other than petroleum continues to expand, solar energy conversion has already been identified as one of the most promising technologies. In the past few years there has been extensive research focused on the next generation solar cells that can exceed the Shockley-Queisser limit (a model that predicts the maximum achievable efficiency for

Sung Jin Kim

2008-01-01

393

Concentrator solar-cell flash tester. [Program SOLAR1 is listed that analyzes data from test  

Microsoft Academic Search

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 solar cell is taken during one flash of a Xenon lamp light source. A comparison of this testing apparatus and an existing outside

Hibray

1982-01-01

394

The New Solar Shape and Oscillations Telescope (NSSOT) Experiment for SOLARNET  

NASA Astrophysics Data System (ADS)

The diameter was observed to be constant over the solar cycle and as such will never be a proper solar-terrestrial climate indicator ground measures with small telescopes are spurius the Maunder Minimum ones of Picard during the XVII century not being an exception Large instruments like the 45 cm Gregorys of Axel Wittmann in Locarno and Tenerife which average seeing cells see no variations ll 40 mas as well as the space instrument MDI SOHO naturally not affected by turbulence either We present the 4 approaches Wittmann on ground with large telescopes Emilio et al 2000 and Kuhn et al 2004 whom used the 6 pixels limb data of MDI Antia 2003 with a completely different method since using the ultra-precise frequency variation of the f-modes and our approach Dam e and Cugnet 2006 using the complete 7 years of filtergrams data 150 000 photograms and magnetograms of the SOHO MDI experiment These 4 careful analysis converge towards the same insignificant below 15 mas variations or even less 0 6 km 0 8 mas in the helioseismology approach Following Antia we can conclude that If a careful analysis is performed then it turns out that there is no evidence for any variation in the solar radius There were no theoretical reasons for large solar radius variations and there is no observational evidence for them with consistent ground and space observations This being stated and admitted the radius measure keeps interest through the solar shape that might change along the cycle sub-surface convective flows

Damé, L.

395

28% efficient GaAs concentrator solar cells  

SciTech Connect

AlGaAs/GaAs heteroface solar concentrator cells which exhibit efficiencies in excess of 27% at high solar concentrations (>400 suns, AM1.5D, 100 mW/cm/sup 2/) have been fabricated with both n/p and p/n configurations. The best n/p cell achieved an efficiency of 28.1% around 400 suns, and the best p/n cell achieved an efficiency of 27.5% around 1000 suns. The high performance of these GaAs concentrator cells compared to our earlier high-efficiency cells was due to improved control of the MOCVD growth conditions and improved cell fabrication procedures (gridline definition and edge passivation). The design parameters of the solar cell structures and optimized grid pattern were determined with a realistic computer modeling program. An evaluation of the device characteristics and implications regarding future GaAs concentrator cell development is presented. 12 refs., 8 figs.

MacMillan, H.F.; Hamaker, H.C.; Kaminar, N.R.; Kuryla, M.S.; Ristow, M.L.; Liu, D.D.; Virshup, G.F.; Gee, J.M.

1988-01-01

396

The physics and modeling of gallium arsenide solar cells  

SciTech Connect

Gallium arsenide is a versatile semiconductor used in many devices. Due to its nearly ideal bandgap energy for solar energy conversion and its compatibility with AlGaAs, gallium arsenide's use in solar cells has been widespread and is growing. Only its chief rival, silicon, is more popular as a high-efficiency material. To continue gallium arsenide's growth, this research was conducted for the purpose of finding improved models for single-crystal GaAs solar cells. The research objectives were: (1) to characterize experimental GaAs cells, (2) to develop predictive device models for AlGaAs/GaAs, and (3) to project the potential of GaAs-based cells. Considering the number of laboratories fabricating GaAs solar cells, there has been a surprisingly limited number of experimental studies that have sought the understanding of GaAs device physics. To extend our knowledge in this area, a study of laboratory-grown cells was conducted. The goal was to uncover the mechanism that limit the performance of today's best GaAs solar cells. The information derived from this study has been used to develop improved models that successfully predict GaAs solar-cell performance. A two-dimensional numerical simulation program, capable of modeling GaAs/AlGaAs heterostructures, was developed. The simulation program is the culmination of earlier research efforts to GaAs/AlGaAs device modeling. It is not possible, using the numerical simulation program, to accurately assess the potential of GaAs solar cells. The numerical model projects conversion efficiencies of over 30% under concentrated sunlight, supporting earlier forecasts that GaAs could play an integral part of future solar-cell technology.

DeMoulin, P.D.

1988-01-01

397

Microcrystalline silicon solar cells deposited at high rates  

NASA Astrophysics Data System (ADS)

Hydrogenated microcrystalline silicon (?c-Si:H) thin-film solar cells were prepared at high rates by very high frequency plasma-enhanced chemical vapor deposition under high working pressure. The influence of deposition parameters on the deposition rate (RD) and the solar cell performance were comprehensively studied in this paper, as well as the structural, optical, and electrical properties of the resulting solar cells. Reactor-geometry adjustment was done to achieve a stable and homogeneous discharge under high pressure. Optimum solar cells are always found close to the transition from microcrystalline to amorphous growth, with a crystallinity of about 60%. At constant silane concentration, an increase in the discharge power did hardly increase the deposition rate, but did increase the crystallinity of the solar cells. This results in a shift of the ?c-Si:H/a-Si:H transition to higher silane concentration, and therefore leads to a higher RD for the optimum cells. On the other hand, an increase in the total flow rate at constant silane concentration did lead to a higher RD, but lower crystallinity. With this shift of the ?c-Si:H/a-Si:H transition at higher flow rates, the RD for the optimum cells decreased. A remarkable structure development along the growth axis was found in the solar cells deposited at high rates by a ``depth profile'' method, but this does not cause a deterioration of the solar cell performance apart from a poorer blue-light response. As a result, a ?c-Si:H single-junction p-i-n solar cell with a high efficiency of 9.8% was deposited at a RD of 1.1 nm/s.

Mai, Y.; Klein, S.; Carius, R.; Wolff, J.; Lambertz, A.; Finger, F.; Geng, X.

2005-06-01

398

Approaches to Future Generation Photovoltaics and Solar Fuels: Quantum Dots, Arrays, and Quantum Dot Solar Cells  

SciTech Connect

One potential, long-term approach to more efficient and lower cost future generation solar cells for solar electricity and solar fuels is to utilize the unique properties of quantum dots (QDs) to control the relaxation pathways of excited states to enhance multiple exciton generation (MEG). We have studied MEG in close-packed PbSe QD arrays where the QDs are electronically coupled in the films and thus exhibit good transport while still maintaining quantization and MEG. We have developed simple, all-inorganic solution-processable QD solar cells that produce large short-circuit photocurrents and power conversion efficiencies above 5% via nanocrystalline p-n junctions. These solar cells show QYs for photocurrent that exceed 100% in the photon energy regions where MEG is possible; the photocurrent MEG QYs as a function of photon energy match those determined via time-resolved spectroscopy Recent analyses of the major effect of MEG combined with solar concentration on the conversion efficiency of solar cells will also be discussed.

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

2012-01-01

399

Decolorizing textile wastewater with Fenton's reagent electrogenerated with a solar photovoltaic cell  

Microsoft Academic Search

In this work it is demonstrated that Fenton's reagent can be electroproduced with abundant and cheap feedstock: oxygen saturated wastewater and solar energy. Experiments were carried out in a divided electrochemical flow cell using two electrodes: a three dimensional reticulated vitreous carbon cathode and stainless steel anode. Fenton's reagent is produced by oxygen reduction on the cathode in the presence

Sandra Figueroa; Leticia Vázquez; A. Alvarez-Gallegos

2009-01-01

400

Consciousness can reduce the voltage of the output signal of solar cell  

Microsoft Academic Search

When the sun's light radiate on the solar cell, it can produce the output signal as the pho- tocurrent. We use the Data Acquisition Modules to record the voltage of the output signals. The v1 is voltage of the photocurrent of solar cell1; The v2 is the one of solar cell2. And these two solar cells stay side by side.

Dayong Cao

2011-01-01

401

Simulation of solar cells utilization on the surface of Mars  

NASA Astrophysics Data System (ADS)

Results concerning the simulation of solar cells operation on Mars surface are reported in this article. PV arrays based on silicon and gallium arsenide solar cells are analyzed under the assumption of both ideal and present state-of-the-art technology. Measurements performed by the Viking Landers are used as inputs. They refer to ambient temperature, wind speed and the optical depth of the Martian atmosphere. The incoming global solar radiation flux (direct, diffuse and ground reflected) is computed by using a model previously proposed by the author. A thermodynamic model of solar cell is developed. Simulations were performed for both Viking Landers 1 and 2 sites during all the four Martian seasons. Information about the optimum voltage and cell temperature is provided as well as details about the electric power supply and cell efficiency. Different sorts of stationary and tracking solar cells arrays are studied. The PV efficiency is obviously higher than that obtained under terrestrial conditions due to the lower ambient temperature on Mars. One confirms that the low operating temperatures will reduce the advantage in efficiency of GaAs solar cells over silicon. The strategy to be chosen for maximum power supply mainly depends on the atmospheric optical depth.

Badescu, Viorel

402

Advanced cost-effective crystalline silicon solar cell technologies  

Microsoft Academic Search

An overview is given concerning current industrial technologies, near future improvements and medium-term developments in the field of industrially viable crystalline silicon terrestrial solar cell fabrication (without concentration).

J. F Nijs; J Szlufcik; J Poortmans; S Sivoththaman; R. P Mertens

2001-01-01

403

Amorphous silicon/polycrystalline thin film solar cells.  

National Technical Information Service (NTIS)

An improved photovoltaic solar cell is described including a p-type amorphous silicon layer, intrinsic amorphous silicon, and an n-type polycrystalline semiconductor such as cadmium sulfide, cadmium zinc sulfide, zinc selenide, gallium phosphide, and gall...

H. S. Ullal

1991-01-01

404

Process Technology and Advanced Concepts: Organic Solar Cells (Fact Sheet)  

SciTech Connect

Capabilities fact sheet for the National Center for Photovoltaics: Process Technology and Advanced Concepts: Organic Solar Cell that includes scope, core competencies and capabilities, and contact/web information.

Not Available

2011-06-01

405

Thin-film silicon and GaAs solar cells  

SciTech Connect

The growth of thin films of crystalline silicon and GaAs on inexpensive substrates offers the promise of combining the high performance of single crystal solar cells with the low cost of thin-film solar cells. The large number of potential crystal growth processes for achieving the desired structure can be organized into melt growth, vapor phase growth, solid state growth and solution growth. Solution growth offers several advantages for the development of solar cell quality material on dissimilar substrates. Thin solar cell design, the selection criteria that led to the choice of solution growth, a description of the growth stages and the growth of silicon on glass and steel and GaAs on aluminum are described.

Barnett, A.M.; Hall, I.W.; Hall, R.B.; Mauk, M.G.; McNeely, J.B.; Tiller, W.A.; Zolper, J.C.

1984-05-01

406

Plasmonic nano-antenna a-Si:H solar cell.  

PubMed

In this work the effects of plasmonics, nano-focusing, and orthogonalization of carrier and photon pathways are simultaneously explored by measuring the photocurrents in an elongated nano-scale solar cell with a silver nanoneedle inside. The silver nanoneedles formed the support of a conformally grown hydrogenated amorphous silicon (a-Si:H) n-i-p junction around it. A spherical morphology of the solar cell functions as a nano-lens, focusing incoming light directly on the silver nanoneedle. We found that plasmonics, geometric optics, and Fresnel reflections affect the nanostructured solar cell performance, depending strongly on light incidence angle and polarization. This provides valuable insight in solar cell processes in which novel concepts such as plasmonics, elongated nanostructures, and nano-lenses are used. PMID:23262683

Di Vece, Marcel; Kuang, Yinghuan; van Duren, Stephan N F; Charry, Jamie M; van Dijk, Lourens; Schropp, Ruud E I

2012-12-01

407

Method of applying an antireflective coating to a solar cell  

SciTech Connect

A tantalum oxide antireflective coating is applied to a surface of a solar energy cell by depositing a layer of a suboxide of tantalum on the surface and then oxidizing the layer to an oxide approaching ta2o5.

Lindmayer, J.

1980-05-06

408

Thermoelastic Analysis of Solar Cell Arrays and Their Material Properties.  

National Technical Information Service (NTIS)

A thermoelastic stress analysis procedure is reported for predicting the thermally induced stresses and failures in silicon solar cell arrays. A prerequisite for the analysis is the characterization of the temperature-dependent thermal and mechanical prop...

M. A. Salama R. K. Yasui W. M. Rowe

1973-01-01

409

Epitaxial Solar Cells on Silicon EFG 'Ribbon' Substrates.  

National Technical Information Service (NTIS)

Epitaxial solar cell structures grown on polycrystalline silicon 'ribbon' substrates (prepared by the edge-defined-growth process) are compared to devices made by direct diffusion into similar material. Efficiency values of 10% (AM-1) have been achieved b...

H. Kressel R. V. D'Aiello P. H. Robinson

1975-01-01

410

Hybrid polymer solar cell based on cadmium selenide quantum dots  

NASA Astrophysics Data System (ADS)

High quality CdSe quantum dots (QDs) were synthesized using the hot injection method. These QDs were further used for the fabrication of Hybrid polymer solar cell (HPSC) using the low band gap polymer such as P3HT. The CdSe QD sensitized polymer solar cell was fabricated using the spin coating technique. The obtained HPSC is further characterized for their optical and solar cell studies. The optical absorbance and photoluminescence of the HPSC is in the visible regime. The solar cell O/P characteristics under 1 Sun illumination produced a promising 0.6% efficiency. The corresponding current density and open circuit photovoltage values were 0.88 mA/cm2 and 278 mV respectively.

More, Anup J.; Pawar, Sachin A.; Burungale, Vishal V.; Patil, Raghunath S.; Patil, Pramod S.

2013-06-01

411

Improved bulk heterojunction organic solar cells employing C70 fullerenes  

NASA Astrophysics Data System (ADS)

We show that the fullerene C70 is suitable to replace fullerene C60, which is commonly used as electron transporter and acceptor in small-molecule organic solar cells. It is shown that the higher absorption of C70 leads to high external quantum efficiencies of over 50% in the spectral range of 500-700 nm. By optimizing the energy level alignment to hole transport layers, the absorption, and the ratio of C70:zinc phthalocyanine (ZnPc) in a bulk heterojunction solar cell, an efficiency of ?=2.87% is achieved. This is a substantial improvement over an identical solar cell employing C60 having ?=2.27%. The efficiency increase is due to a higher photocurrent, while fill factor and open-circuit voltage for C70 and C60-containing organic solar cells remain comparable.

Pfuetzner, Steffen; Meiss, Jan; Petrich, Annette; Riede, Moritz; Leo, Karl

2009-06-01

412

High-efficiency heterojunction solar cells on crystalline germanium substrates  

NASA Astrophysics Data System (ADS)

We report stand-alone heterojunction (HJ) solar cells with conversion efficiencies of 5.9% and 7.2% on n-type and p-type crystalline germanium (c-Ge) substrates, respectively. The emitter of the HJ solar cells is formed by growing thin layers of highly doped hydrogenated microcrystalline silicon using plasma-enhanced chemical vapor deposition at temperatures close to 200 °C. The conversion efficiencies of the HJ solar cells are well-comparable with conventional devices fabricated at temperatures as high as 600 °C. We also study the surface passivation of c-Ge with hydrogenated amorphous and microcrystalline Si and correlate the passivation quality with the electrical performance of the HJ solar cells.

Hekmatshoar, Bahman; Shahrjerdi, Davood; Hopstaken, Marinus; Fogel, Keith; Sadana, Devendra K.

2012-07-01

413

Investigation of the texture surface silicon solar cell  

SciTech Connect

The optical and electrical properties of the texture surface silicon solar cell are analyzed and discussed. A new method of etching a texture surface by LiOH is presented and the mechanism of etching a texture surface is investigated.

Rongqiang, C.; Huilan, Q.

1983-10-01

414

European Roadmap of Multijunction Solar Cells and Qualification Status  

Microsoft Academic Search

A program for the development and qualification of advanced triple-junction space solar cells in Europe was initiated and supported by the European Space Agency ESA (contracts No. 18767\\/04\\/NL\\/FM \\

G. F. X. Strobl; T. Bergunde; W. Kostler; R. Kern; M. Meusel; G. Laroche; W. Zimmermann; A. W. Bett; F. Dimroth; W. Geens; S. Taylor; E. Fernandez; L. Gerlach; C. Signorini; G. Hey

2006-01-01

415

Plasmonic reflection grating back contacts for microcrystalline silicon solar cells  

NASA Astrophysics Data System (ADS)

We report on the fabrication and optical simulation of a plasmonic light-trapping concept for microcrystalline silicon solar cells, consisting of silver nanostructures arranged in square lattice at the ZnO:Al/Ag back contact of the solar cell. Those solar cells deposited on this plasmonic reflection grating back contact showed an enhanced spectral response in the wavelengths range from 500 nm to 1000 nm, when comparing to flat solar cells. For a particular period, even an enhancement of the short circuit current density in comparison to the conventional random texture light-trapping concept is obtained. Full three-dimensional electromagnetic simulations are used to explain the working principle of the plasmonic light-trapping concept.

Paetzold, U. W.; Moulin, E.; Michaelis, D.; Böttler, W.; Wächter, C.; Hagemann, V.; Meier, M.; Carius, R.; Rau, U.

2011-10-01

416

High Temperature Bonding Techniques for Solar Cell Array.  

National Technical Information Service (NTIS)

An adhesive for solar cell attachment to spacecraft substrates has been sought with an unusually demanding combination of properties. These include (1) a basic resistance to decomposition at 600 C in vacuum, (2) retention of elastic properties at liquid n...

G. LaFontaine F. Marsh H. Levin F. Sinsheimer G. Wolff

1977-01-01

417

Hydrogen Radical-Enhanced Growth of Solar Cells.  

National Technical Information Service (NTIS)

High-efficiency solar cells require multiple layers of compound semiconducting materials with different composition and/or doping. They are grown epitaxially in succession on a substrate. Mechanical requirements often specify abrupt changes in both compos...

J. M. Borrego S. K. Ghandhi

1991-01-01

418

Experience with solar systems for heating swimming pools in Germany  

SciTech Connect

The results of the demonstration programme [open quotes]Efficient Use of Energy in Swimming Pool Construction[close quotes] has had a positive effect on the dissipation of solar systems for swimming pools. Infrared measurements show how a homogeneous flow can be achieved in the absorber field. The fact that solar systems are acceptable can be clearly in evidence that the behaviour of visitors to purely solar-heated pools with variable water temperature does not differ in principle from conventionally-heated pools with constant temperature. Economic considerations of the operation show that swimming pool solar systems are competitive with conventional heating systems.

Croy, R.; Peuser, F.A. (Zentralstelle fuer Solartechnik, Hilden (Germany))

1994-07-01

419

Crystalline Si thin-film solar cells: a review  

Microsoft Academic Search

.   The present review summarizes the results of research efforts in the field of crystalline silicon thin-film solar cells on\\u000a foreign substrates. The large number of competing approaches can be broadly classified according to the grain size of the\\u000a crystalline Si films and the doping of the crystalline absorber. Currently, solar cells based on microcrystalline Si films\\u000a on glass with

R. B. Bergmann

1999-01-01

420

Third generation photovoltaics: solar cells for 2020 and beyond  

Microsoft Academic Search

Many working in the field of photovoltaics believe that ‘first generation’ silicon wafer-based solar cells sooner or later will be replaced by a ‘second generation’ of lower cost thin-film technology, probably also involving a different semiconductor. Historically, CdS, a-Si, CuInSe2, CdTe and, more recently, thin-film Si have been regarded as key thin-film candidates. Since any mature solar cell technology is

Martin A Green

2002-01-01

421

Amorphous silicon\\/polycrystalline thin film solar cells  

Microsoft Academic Search

An improved photovoltaic solar cell is described including a p-type amorphous silicon layer, intrinsic amorphous silicon, and an n-type polycrystalline semiconductor such as cadmium sulfide, cadmium zinc sulfide, zinc selenide, gallium phosphide, and gallium nitride. The polycrystalline semiconductor has an energy bandgap greater than that of the amorphous silicon. The solar cell can be provided as a single-junction device or

Ullal

1991-01-01

422

Low temperature quantum efficiency measurements on irradiated multijunction solar cells  

Microsoft Academic Search

This paper presents quantum efficiency (QE) measurements and analyses on monolithic triple junction (3J) InGaP\\/GaAs\\/Ge solar cells under both room (300K) and low temperature (130K) conditions. In measuring the quantum efficiency of multijunction solar cells, one must be careful to use the proper bias conditions to isolate the subcell of interest. This may be achieved by using external light sources

S. R. Messenger; J. H. Warner; P. P. Jenkins; R. J. Walters; J. R. Lorentzen

2008-01-01

423

Simple Photovoltaic Cells for Exploring Solar Energy Concepts  

ERIC Educational Resources Information Center

|Low-efficiency solar cells for educational purposes can be simply made in school or home environments using wet-chemistry techniques and readily available chemicals of generally low toxicity. Instructions are given for making solar cells based on the heterojunctions Cu/Cu[subscript 2]O, Cu[subscript 2]O/ZnO and Cu[subscript 2]S/ZnO, together with…

Appleyard, S. J.

2006-01-01

424

Silicon nanocrystals - a luminescence convertor applied to silicon solar cells  

Microsoft Academic Search

In this contribution we investigate an implementation of silicon nanocrystals (Si-nc) into photovoltaic in order to improve the performance of the solar cells. The Si-nc are prepared ex-situ from porous silicon and embedded into SiO\\/sub 2\\/ based spin-on-glasses (SOG) layers and deposited on standard silicon solar cell. We are presenting the photo luminescence properties of such a SOG\\/Si-nc layers. When

V. Svrcek; A. Slaoui; J.-C. Muller

2003-01-01

425

Recent technological advances in thin film solar cells  

SciTech Connect

High-efficiency, low-cost thin film solar cells are an exciting photovoltaic technology option for generating cost-effective electricity in 1995 and beyond. This paper reviews the substantial advances made by several thin film solar cell technologies, namely, amorphous silicon, copper indium diselenide, cadmium telluride, and polycrystalline silicon. Recent examples of utility demonstration projects of these emerging materials are also discussed. 8 refs., 4 figs.

Ullal, H.S.; Zwelbel, K.; Surek, T.

1990-03-01

426

High-efficiency panchromatic hybrid Schottky solar cells.  

PubMed

Nanostructured Schottky inorganic-organic solar cells provide overall power conversion efficiencies exceeding 3%, with extremely large short-circuit photocurrents. The device EQE faithfully tracks the absorptance of the CdSe nanorods, and the IQE is approximately constant over the entire visible spectrum as opposed to a p-n junction hybrid solar cell fabricated with a highly absorbing organic polymer. PMID:23090941

Lee, Joun; Mubeen, Syed; Hernandez-Sosa, Gerardo; Sun, Yanming; Toma, Francesca M; Stucky, Galen D; Moskovits, Martin

2012-10-23

427

Thin film solar cell inflatable ultraviolet rigidizable deployment hinge  

US Patent & Trademark Office Database

A flexible inflatable hinge includes curable resin for rigidly positioning panels of solar cells about the hinge in which wrap around contacts and flex circuits are disposed for routing power from the solar cells to the power bus further used for grounding the hinge. An indium tin oxide and magnesium fluoride coating is used to prevent static discharge while being transparent to ultraviolet light that cures the embedded resin after deployment for rigidizing the inflatable hinge.

Simburger; Edward J. (Agoura, CA); Matsumoto; James H. (Los Angeles, CA); Giants; Thomas W. (Santa Monica, CA); Garcia, III; Alec (Santa Clarita, CA); Perry; Alan R. (Conifer, CA); Rawal; Suraj (Littleton, CO); Marshall; Craig H. (Littleton, CO); Lin; John K. H. (Middletown, DE); Day; Jonathan Robert (Dover, DE); Kerslake; Thomas W. (Strongsville, OH); Scarborough; Stephen E. (Seaford, DE)

2010-05-04

428

Nanocrystalline metal electrodes for high-efficiency organic solar cells  

Microsoft Academic Search

We demonstrate that indium (In) nanocrystals can be used as efficient small-work function electrodes for organic solar cells. A Schottky-barrier solar cell consisting of the In nanoelectrodes, a zinc phthalocyanine (ZnPc) film as a p-type organic semiconductor, and a gold counterelectrode were assembled by vacuum evaporation on an indium-tin-oxide substrate. Nanoscopic Schottky barriers, which are the origins of photovoltaic effects,

Tetsuya Taima; Masayuki Chikamatsu; Yuji Yoshida; Kazuhiro Saito; Kiyoshi Yase

2004-01-01

429

Silicon nanocrystals as a photoluminescence down shifter for solar cells  

Microsoft Academic Search

The effects of a Si-rich silicon oxide (SRO) layer containing silicon nanocrystals as photoluminescence down-shifter layer on a conventional Si solar cell were investigated. Two SRO layers with different thicknesses but same composition were deposited on top of Si solar cells by plasma-enhanced chemical vapor deposition and followed by high temperature annealing to precipitate silicon nanocrystals. The SRO layers absorb

Zhizhong Yuan; Georg Pucker; Alessandro Marconi; Fabrizio Sgrignuoli; Aleksei Anopchenko; Yoann Jestin; Lorenza Ferrario; Pierluigi Bellutti; Lorenzo Pavesi

2011-01-01

430

Polycrystalline silicon on glass for thin-film solar cells  

Microsoft Academic Search

Although most solar cell modules to date have been based on crystalline or polycrystalline wafers, these may be too material\\u000a intensive and hence always too expensive to reach the very low costs required for large-scale impact of photovoltaics on the\\u000a energy scene. Polycrystalline silicon on glass (CSG) solar cell technology was developed to address this difficulty as well\\u000a as perceived

Martin A. Green

2009-01-01

431

Engineering-scale experiments of solar photocatalytic oxidation of trichloroethylene  

SciTech Connect

A photocatalytic process is being developed to destroy organic contaminants in water. Tests with a common water pollutant, trichlorethylene (TCE), were conducted at the Solar Thermal Test Facility at Sandia with trough systems. Tests at this scale provide verification of laboratory studies and allow examination of design and operation issues that only arise in experiments on a realistic scale. The catalyst, titanium dioxide (TiO{sub 2}), is a harmless material found in paint, cosmetics and even toothpaste. We examined the effect of initial contaminant concentration and the effect of hydrogen peroxide on the photocatalytic decomposition of trichlorethylene (TCE). An aqueous solution of 5000 parts per billion (ppB) TCE with 0.1 weight {percent} suspended titanium dioxide catalyst required approximately 4.2 minutes of exposure to destroy the TCE to a detection limit of 5 ppB. For a 300 ppB TCE solution, the time required was only 2.5 minutes to reach the same level of destruction. Adding 250 parts per million (ppM) of hydrogen peroxide reduced the time required by about 1 minute. A two parameter Langmuir Hinshelwood model was able to describe the data. A simple flow apparatus was built to test four fixed catalyst supports and to measure their pressure drop and assess their ability to withstand flow conditions typical of a full-sized system. In this paper, we summarize the engineering-scale testing and results. 16 refs., 5 figs.

Pacheco, J.; Prairie, M.; Evans, L.; Yellowhorse, L.

1990-01-01

432

Stem cell transplantation; Iranian experience.  

PubMed

From March 1991 through 31st December 2007, 2042 patients underwent stem cell transplantation at the Hematology-Oncology and Stem Cell Transplantation Research Center, affiliated to Tehran University of Medical Sciences. These transplantations included 1405 allogeneic stem cell transplantation, 624 autologous stem cell transplantation, and 13 syngeneic stem cell transplantation. Stem cell transplantation was performed for various diseases including acute myelogenous leukemia, acute lymphoblastic leukemia, chronic myelogenous leukemia, chronic lymphoblastic leukemia, thalassemia major, sickle cell thalassemia, sickle cell disease, multiple myeloma, myelodysplasia, mucopolysaccharidosis, paroxysmal nocturnal hemoglobinuria, non-Hodgkin's lymphoma, Hodgkin's disease, severe aplastic anemia, plasma cell leukemia, Niemann-Pick disease, Fanconi anemia, severe combine immunodeficiency, congenital neutropenia, leukocyte adhesion deficiencies, Chediak-Higashi syndrome, osteopetrosis, histiocytosis X, Hurler syndrome, amyloidosis, systemic sclerosis, breast cancer, Ewing's sarcoma, testicular cancer, germ cell tumors, neuroblastoma, medulloblastoma, renal cell carcinoma, nasopharyngeal carcinoma, ovarian cancer, Wilms' tumor, rhabdomyosarcoma, pancreatoblastoma, and multiple sclerosis. We had 105 cellular therapies for postmyocardial infarction, multiple sclerosis, cirrhosis, head of femur necrosis, and renal cell carcinoma. About 30 patients were retransplanted in this center. About 74.9% of the patients (1530 of 2042) remained alive between one to 168 months after stem cell transplantation. Nearly 25.1% (512 of 2042) of our patients died after stem cell transplantation. The causes of deaths were relapse, infections, hemorrhagic cystitis, graft versus host disease, and others. PMID:19111033

Ghavamzadeh, Ardeshir; Alimoghaddam, Kamran; Alimogaddam, Kamran; Jahani, Mohammad; Mousavi, Seied Asadollah; Mousavi, Seyed Asadollah; Iravani, Masood; Bahar, Babak; Khodabandeh, Ali; Khatami, Farnaz; Ghaffari, Fatemeh; Jalali, Arash

2009-01-01

433

Polymer solar cells with enhanced fill factors  

NASA Astrophysics Data System (ADS)

Recent advances in polymer solar cell (PSC) performance have resulted from compressing the bandgap to enhance the short-circuit current while lowering the highest occupied molecular orbital to increase the open-circuit voltage. Nevertheless, PSC power conversion efficiencies are still constrained by low fill factors, typically below 70%. Here, we report PSCs with exceptionally high fill factors by combining complementary materials design, synthesis, processing and device engineering strategies. The donor polymers, PTPD3T and PBTI3T, when incorporated into inverted bulk-heterojunction PSCs with a PC71BM acceptor, result in PSCs with fill factors of 76-80%. The enhanced performance is attributed to highly ordered, closely packed and properly oriented active-layer microstructures with optimal horizontal phase separation and vertical phase gradation. The result is efficient charge extraction and suppressed bulk and interfacial bimolecular recombination. The high fill factors yield power conversion efficiencies of up to 8.7% from polymers with suboptimal bandgaps, suggesting that efficiencies above 10% should be realizable by bandgap modification.

Guo, Xugang; Zhou, Nanjia; Lou, Sylvia J.; Smith, Jeremy; Tice, Daniel B.; Hennek, Jonathan W.; Ortiz, Rocío Ponce; Navarrete, Juan T. López; Li, Shuyou; Strzalka, Joseph; Chen, Lin X.; Chang, Robert P. H.; Facchetti, Antonio; Marks, Tobin J.

2013-10-01

434

High efficacy thinned four-junction solar cell  

NASA Astrophysics Data System (ADS)

A thinned four-junction (4J) 1.88 eV GaInP/1.41 eV GaInAs/0.92 eV GaInNAs(Sb)/0.66 eV Ge solar cell is analyzed here versus the benchmark optically thick GaInP/GaInAs/Ge three-junction (3J) solar cell. Despite purposefully reducing the one sun AM1.5D current density to 12.4 mA cm-2 in the III-V subcells and 13.6 mA cm-2 in the bottom Ge subcell (1.2 mA cm-2 excess current density) and using less than 1.0 eV bandgap for the third subcell, ~3% higher theoretical power conversion efficiency is possible along with ~27% less parasitic resistive (I2R) power loss and ~45% less epitaxially grown compound semiconductor material in comparison to the benchmark three-junction solar cell. If we consider the efficacy of the solar cells in terms of power (W) per epitaxial layer thickness (µm), then the thinned 4J solar cell has ~93% greater efficacy (W/µmepilayer) than the benchmark 3J solar cell. Additionally, compositionally graded versus fixed composition passivating window and back surface field layers for improved charge carrier transport are examined.

Kirk, A. P.

2011-12-01

435

OTEC to hydrogen fuel cells - A solar energy breakthrough  

Microsoft Academic Search

Recent advances in fuel cell technology and development are discussed, which will enhance the Ocean Thermal Energy Conversion (OTEC)-hydrogen-fuel cell mode of energy utilization. Hydrogen obtained from the ocean solar thermal resources can either be liquified or converted to ammonia, thus providing a convenient mode of transport, similar to that of liquid petroleum. The hydrogen fuel cell can convert hydrogen

J. R. Roney

1981-01-01

436

Solar Cell is Housed in Light-Bulb Enclosure: An inexpensive solar-cell module uses a standard outdoor light-bulb enclosure.  

National Technical Information Service (NTIS)

This citation summarizes a one-page announcement of technology available for utilization. With the advent of a recently announced innovation in solar cell fabrication, the planar multijunction (PMJ) high voltage solar cell have been found. Housed in a con...

1981-01-01

437

Experience on integration of solar thermal technologies with green buildings  

Microsoft Academic Search

The green buildings of Shanghai Research Institute of Building Science include an office building for the demonstration of public building and two residential buildings, which are for the demonstration of flat and villa, respectively. Here, a solar-powered integrated energy system including heating, air-conditioning, natural ventilation and hot water supply was designed and constructed for the office building. However, only solar

X. Q. Zhai; R. Z. Wang; Y. J. Dai; J. Y. Wu; Q. Ma

2008-01-01

438

Experience in constructing a solar energy cadastral survey  

Microsoft Academic Search

Basic purposes of a solar energy cadastral survey incorporating objective numerical data based on an adequate stochastic model are outlined. The survey is intended to provide a data base for exploitation and storage of solar energy and for forecasting of favorable insolation conditions, with benefits in electric power, communications, refrigeration and heating, irrigation, and water resources management. The microstructure of

R. B. Salieva

1977-01-01

439

Solar receiver experiment for the space station Freedom Brayton engine  

Microsoft Academic Search

This paper reports on an experimental investigation conducted to develop fabrication procedures and acquire test data for a heat receiver assembly (HRA) in support of the design and development effort for the Brayton engine solar receiver for the NASA space station freedom solar dynamic option. The HRA configuration is a cylindrical receiver lined with tubes; each tube is surrounded by

Hal J. Strumpf; Murray G. Coombs

1990-01-01

440

Low temperature MRFM probe development and initial characterization of organic solar cells  

NASA Astrophysics Data System (ADS)

We report on the construction of a Magnetic Resonance Force Microscope (MRFM) for organic solar cell characterization. Organic bulk-heterojunction solar cells (OSCs) consist of a blend of two organic semiconductors- an electron donating polymer and an electron accepting fullerene. The efficiency of blended OSCs is highly dependent on the phase separation between the donor and acceptor materials. MRFM offers a unique toolset to study OSCs with the potential to gain insight into the morphology of the buried heterostructure on an actual device. The MRFM probe will operate at 4K and up to 9T using force gradient detection of magnetic resonance via an ultra sensitive single crystal silicon cantilever. We plan on performing NMR spectroscopy on OSCs using a shuttling technique whereby the sample is shuttled far from the gradient magnetic particle during the encoding portion of the NMR RF pulses. We will present on the status of the probe development and on our initial experiments on organic solar cells.

Monti, Mark; Alexson, Dimitri; Smith, Doran

2013-03-01

441

Visibly transparent polymer solar cells produced by solution processing.  

PubMed

Visibly transparent photovoltaic devices can open photovoltaic applications in many areas, such as building-integrated photovoltaics or integrated photovoltaic chargers for portable electronics. We demonstrate high-performance, visibly transparent polymer solar cells fabricated via solution processing. The photoactive layer of these visibly transparent polymer solar cells harvests solar energy from the near-infrared region while being less sensitive to visible photons. The top transparent electrode employs a highly transparent silver nanowire-metal oxide composite conducting film, which is coated through mild solution processes. With this combination, we have achieved 4% power-conversion efficiency for solution-processed and visibly transparent polymer solar cells. The optimized devices have a maximum transparency of 66% at 550 nm. PMID:22789123

Chen, Chun-Chao; Dou, Letian; Zhu, Rui; Chung, Choong-Heui; Song, Tze-Bin; Zheng, Yue Bing; Hawks, Steve; Li, Gang; Weiss, Paul S; Yang, Yang

2012-07-12

442

New directions in InP solar cell research  

SciTech Connect

Recent research efforts representing new directions in InP solar cell research are reviewed. These include heteroepitaxial growth on silicon and gallium arsenide substrates, V-grooved cells, large area high efficiency cells, and surface passivation. Improvements in heteroepitaxial cell efficiency are described together with processing of 19.1 percent, 4 sq cm cells. Recommendations are made for improvements in processing leading to increased efficiencies.

Weinberg, I.; Swartz, C.K.; Brinker, D.J.

1990-01-01

443

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

SciTech Connect

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

Roo-Ons, M.J.; Shynu, S.V.; Ammann, M.J. [Antenna and High Frequency Research Centre, School of Electronic and Communications Engineering, Dublin Institute of Technology (Ireland); Seredynski, M. [Institute of Heat Engineering, Warsaw University of Technology (Poland); McCormack, S.J. [Dept. of Civil, Structural and Environmental Engineering, Trinity College Dublin (Ireland); Norton, B. [Dublin Energy Lab., Focas Institute, Dublin Institute of Technology (Ireland)

2010-09-15

444

Heat pipe-based cooling systems for photovoltaic cells under concentrated solar radiation  

Microsoft Academic Search

Concentrating solar radiation onto photovoltaic solar cells does not generally produce a uniform distribution of solar radiation at the surface of the cells. In this work a unique profile for the reflecting surfaces has been developed such that the solar cells are evenly illuminated under any degree of concentration. Also introduced is a passive method based on thermosyphons which can

A. Akbarzadeh; T. Wadowski

1996-01-01

445

Performance Degradation of Czochralski-Grown Silicon Solar Cells by Means of Current Injection  

Microsoft Academic Search

Performance degradation of Czochralski-grown silicon (Cz-Si) solar cells caused by forward bias voltage application has been investigated. Because of the similarity to light-induced degradation, comparative experiments are carried out on the phenomena. Cell performance decay time evaluations reveal that current injection has a weaker effect on the degradation than illumination in the low-injection region. A difference in the energy of

Hiroshi Hashigami; Marwan Dhamrin; Tadashi Saitoh

2002-01-01

446

Department of Energy's solar technology transfer program: the Lawrence Livermore Laboratory experience  

Microsoft Academic Search

The Lawrence Livermore Laboratory (LLL) under the direction of the Department of Energy's (DOE's) Solar Technology Transfer Program (STTP) has designed and implemented a regionalized solar commercialization outreach program. Primary target audiences in Arizona, California, Hawaii and Nevada include architects, builders, lenders, contractors, plumbers, manufacturers, distributors as well as educational institutions, state and local offices, and library systems. The experience

1979-01-01

447

Timonium Elementary School Solar Energy Heating and Cooling Augmentation Experiment. Final Engineering Report. Executive Summary.  

ERIC Educational Resources Information Center

|This report covers a two-year and seven-month solar space heating and cooling experiment conducted at the Timonium Elementary School, Timonium, Maryland. The system was designed to provide a minimum of 50 percent of the energy required during the heating season and to determine the feasibility of using solar energy to power absorption-type…

AAI Corp., Baltimore, MD.

448

Solar Energy School Heating Augmentation Experiment. Design, Construction and Initial Operation. A Report.  

ERIC Educational Resources Information Center

This report describes an experimental solar heating system, complete with thermal storage and controls, that has met all the heating requirements of five detached classrooms of the Fauquier High School in Warrenton, Virginia. The objectives of the experiment were to (1) demonstrate that solar energy can be used to provide a substantial part of the…

InterTechnology Corp., Warrenton, VA.

449

The reality of living in passive solar homes: A user-experience study  

Microsoft Academic Search

This paper presents a study of a user-experience survey about living in passive solar homes. It was carried out at the Energy Park located in the western part of Milton Keynes. The survey focuses on the reality of living in passive solar homes as perceived or experienced by the occupant. It is hoped that the findings would come to bear

GS Yakubu

1996-01-01

450

35,000-kW-hr Later A User's Experience of Photovoltaic Solar Panels  

Microsoft Academic Search

Petroleum Development Oman (PDO) has nearly 3 years' field experience with photovoltaic solar panels powering an extensive chain of microwave radio repeaters along main oil pipelines. Solar generator and load currents are integrated by onsite instrumentation and the results have been recorded monthly. Computer analysis has allowed detailed performance monitoring as well as building up a data bank for the

G. S. M. Teale; G. S. M

1984-01-01

451

Timonium Elementary School Solar Energy Heating and Cooling Augmentation Experiment. Final Engineering Report. Executive Summary.  

ERIC Educational Resources Information Center

This report covers a two-year and seven-month solar space heating and cooling experiment conducted at the Timonium Elementary School, Timonium, Maryland. The system was designed to provide a minimum of 50 percent of the energy required during the heating season and to determine the feasibility of using solar energy to power absorption-type…

AAI Corp., Baltimore, MD.

452

Definitive design of the solar total energy large-scale experiment at Shenandoah, Georgia  

Microsoft Academic Search

Construction of a Solar Total Energy Large Scale Experiment at Shenandoah, Georgia, is described. The Solar Total Energy System (STES) is designed with capacity to supply electricity and thermal energy to a knitwear plant at the Shenandoah site. The system will provide 400 kilowatts electrical and 3.5 megawatts thermal energy. The STES is a cascaded total energy system configuration. It

R. W. Hunke; J. A. Leonard

1981-01-01

453

Disposal of Brine by Solar Evaporation: Laboratory Experiments.  

National Technical Information Service (NTIS)

The investigation reported describes laboratory studies of the effect of salinity, effect of dyes, and design models on solar evaporation of brine. Naphthol Green dye was determined to increase the absorptivity of radiation the greatest of all dyes tested...

C. Morales C. G. Keyes D. C. Winans H. R. Pritchett W. S. Gregory

1970-01-01

454

Solar wind turbulence during the solar cycle deduced from Galileo coronal radio-sounding experiments  

NASA Astrophysics Data System (ADS)

Seven coronal radio sounding campaigns were carried out during the active lifetime of the Galileo spacecraft in the years 1994-2002 The observational data analyzed in the present work are S-band frequency fluctuation measurements recorded during the solar conjunctions at different phases of solar activity cycle 23 specifically periods near solar maximum 3 conjunctions near solar minimum 3 conjunctions and during the ascending phase 1 conjunction These data are all applicable to low heliocentric latitudes i e to the slow solar wind The mean frequency fluctuation and power-law index of the frequency fluctuation temporal spectra are determined as a function of heliocentric distance The turbulence power spectrum tends to be flatter inside ca 20 solar radii during all phases of the solar cycle This coincides with a transition in the flow from the inner acceleration region to the outer region of constant velocity The radial falloff rate of the mean frequency fluctuation is also invariant over the solar cycle but the absolute level is typically higher at solar maximum compared with that at the minimum phase

Efimov, A. I.; Samoznaev, L. N.; Bird, M. K.; Chashei, I. V.; Plettemeier, D.

455

Results of the 1979 NASA/JPL Balloon Flight Solar Cell Calibration Program.  

National Technical Information Service (NTIS)

Calibration of solar cells to be used as reference standards in simulator testing of cells and arrays was accomplished. Thirty-eight modules were carried to an altitude of about 36 kilometers during the solar cell calibration balloon flight.

C. H. Seaman R. S. Weiss

1980-01-01

456

Field collapse due to band-tail charge in amorphous silicon solar cells.  

National Technical Information Service (NTIS)

It is common for the fill factor to decrease with increasing illumination intensity in hydrogenated amorphous silicon solar cells. This is especially critical for thicker solar cells, because the decrease is more severe than in thinner cells. Usually, the...

Q. Wang R. S. Crandall E. A. Schiff

1996-01-01

457

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

Microsoft Academic Search

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

Veronica Sholin

2008-01-01

458

The Solar-A soft X-ray telescope experiment  

Microsoft Academic Search

The Japanese Solar-A mission for the study of high energy solar physics is timed to observe the sun during the next activity maximum. This small spacecraft includes a carefully coordinated complement of instruments for flare studies. In particular, the soft X-ray telescope (SXT) will provide X-ray images of flares with higher sensitivity and time resolution than have been available before.

L. Acton; M. Bruner; W. Brown; J. Lemen; T. Hirayama

1988-01-01

459

Adsorptive solar powered ice maker: experiments and model  

Microsoft Academic Search

A solar adsorptive ice maker model is presented and experimentally validated. In order to determine the model parameters, the identification procedure is carried out employing an experimental data base obtained from tests carried out on two adsorptive solar-powered ice-makers using a methanol\\/carbon pair. The packaged component, the collector–condenser, represents the main new feature of these units. The prediction is compared

A. Boubakri; J. J. Guilleminot; F. Meunier

2000-01-01

460

Solar energy powered microbial fuel cell with a reversible bioelectrode.  

PubMed

The solar energy powered microbial fuel cell is an emerging technology for electricity generation via electrochemically active microorganisms fueled by solar energy via in situ photosynthesized metabolites from algae, cyanobacteria, or living higher plants. A general problem with microbial fuel cells is the pH membrane gradient which reduces cell voltage and power output. This problem is caused by acid production at the anode, alkaline production at the cathode, and the nonspecific proton exchange through the membrane. Here we report a solution for a new kind of solar energy powered microbial fuel cell via development of a reversible bioelectrode responsible for both biocatalyzed anodic and cathodic electron transfer. Anodic produced protons were used for the cathodic reduction reaction which held the formation of a pH membrane gradient. The microbial fuel cell continuously generated electricity and repeatedly reversed polarity dependent on aeration or solar energy exposure. Identified organisms within biocatalyzing biofilm of the reversible bioelectrode were algae, (cyano)bacteria and protozoa. These results encourage application of solar energy powered microbial fuel cells. PMID:19961218

Strik, David P B T B; Hamelers, Hubertus V M; Buisman, Cees J N

2010-01-01

461

Solar district heating with evacuated collectors: First year experience of the Knivsta plant  

NASA Astrophysics Data System (ADS)

The experience gained during the summer enable some practical demands to be placed on solar collectors, namely: it must be possible to easily replace a solar collector without emptying the system; it must be easy to bleed the system; solar collectors must be able to withstand overheating due to boiling; and obvious leakage risks must be eliminated. There is no doubt that not all types of evacuated solar collectors fulfill these requirements and that further development is essential before large-scale installations with rational operation can be considered.

Kjellson, E.; Perers, B.; Zinko, H.; Astrand, L.

462

The electronic systems for the Gamma Ray Experiment for the Solar Maximum Mission  

NASA Astrophysics Data System (ADS)

The Gamma Ray Experiment (GRE) is one of the seven instruments on the Solar Maximum Mission. The scientific objective of the GRE is to study solar gamma ray emissions expected during, and, according to some solar models, prior to solar flares. The instrument consists of a detector assembly and a remote electronic assembly. The latter includes redundant low-voltage power supplies and the remaining command, data handling, and ancillary electronic subsystems of the instrument. The electronic systems and subsystems of the instrument are described in some detail.

Staples, M.; Gleske, I.; Kubierschky, K.

1980-02-01

463

Combined solution effects yield stable thin-film Cd(Se,Te)/polysulfide photoelectrochemical solar cells  

SciTech Connect

Photocurrent-voltage and long-term stability (greater than a year) results of thin-film Cd(Se,Te)/aqueous polysulfide photoelectrochemical solar cells (PEC) are presented. In outdoor experiments, it is demonstrated that small modifications of polysulfide electrolyte composition can increase cadmium chalcogenide/polysulfide PEC solar cell lifetimes from months to years. After an initial small rise and fall in solar to electrical conversion efficiency, a photoelectrochemical solar cell, containing a pasted thin-film Cd(Se,Te) photoelectrode immersed in an electrolyte of 1.8 M Cs/sub 2/S and 3 M S, exhibited complete stability (for an 8-month outdoors operation) at 4.1% conversion efficiency. Optimization of (i) nominal sulfide concentration, (ii) the ratio of dissolved sulfur to sulfide, (iii) removal of hydroxide, and (iv) correct choice of cation (cesium) in polysulfide electrolyte, in addition to increasing solution or cell stability, improves thin-film and single-crystal Cd(Se,Te) solar to electrical relative efficiencies by 24% and 65%, respectively, when compared to those in commonly used polysulfide electrolytes. 26 references, 3 figures, 1 table.

Licht, S.

1986-03-13

464

Progress in InP solar cell research  

NASA Astrophysics Data System (ADS)

Progress, in the past year, in InP solar cell research is reviewed. Small area cells with AMO, total area efficiencies of 18.8 percent were produced by OMCVD and Ion Implantation. Larger area cells (2 and 4 sq cm) were processed on a production basis. One thousand of the 2 sq cm cells will be used to supply power to a small piggyback lunar orbiter scheduled for launch in February 1990. Laboratory tests of ITO/InP cells, under 10 MeV proton irradiation, indicate radiation resistance comparable to InP n/p homojunction cells. Computer modeling studies indicate that, for identical geometries and dopant concentrations, InP solar cells are significantly more radiation resistant than GaAs under 1 MeV electron irradiation. Additional computer modeling calculations were used to produce rectangular and circular InP concentrator cell designs for both the low concentration SLATS and higher concentration Cassegrainian Concentrators.

Weinberg, Irving; Brinker, David J.

465

Progress in InP solar cell research  

NASA Astrophysics Data System (ADS)

Progress, in the past year, in InP solar cell research is reviewed. Small area cells with AMO, total area efficiencies of 18.8 percent were produced by OMCVD and Ion Implantation. Larger area cells (2 and 4 sq cm) were processed on a production basis. One thousand of the 2 sq cm cells will be used to supply power to a small piggyback lunar orbiter scheduled for launch in February 1990. Laboratory tests of ITO/InP cells, under 10 MeV proton irradiation, indicate radiation resistance comparable to InP n/P homojunction cells. Computer modeling studies indicate that, for identical geometries and dopant concentrations, InP solar cells are significantly more radiation resistant than GaAs under 1 MeV electron irradiation. Additional computer modeling calculations were used to produce rectangular and circular InP concentrator cell designs for both the low concentration SLATS and higher concentration Cassegrainian Concentrators.

Weinberg, I.; Brinker, D. J.

466

Multilevel metallization for large area point-contact solar cells  

NASA Astrophysics Data System (ADS)

An analysis of the series resistances of different metallization schemes for large-area backside-contact (BC) solar cells is presented. The need for developing a multilevel metallization technology for such cells is demonstrated. The authors propose a new design for the metallization of BC cells that presents a series resistance independent of the cell size. The particular features required for such a multilevel interconnection are studied, and a process using anodic oxidation of aluminum is presented. BC silicon solar cells of 0.64 sq cm have been processed in this technology, resulting in 26.2 percent efficiencies at 10 W/sq cm (100 suns AM1.5, 25.5 deg C). Subsequent runs with a simplified process and a new cell design have given 27.3 percent efficiency cells. The cells have been soldered on alumina mounts. Results of thermal cycling are given.

Verlinden, P.; Swanson, R. M.; Sinton, R. A.; Kane, D. E.

467

Cell motility: Combining experiments with modeling  

NASA Astrophysics Data System (ADS)

Cell migration and motility is a pervasive process in many biology systems. It involves intra-cellular signal transduction pathways that eventually lead to membrane extension and contraction. Here we describe our efforts to combine quantitative experiments with theoretical and computational modeling to gain fundamental insights into eukaryotic cell motion. In particular, we will focus on the amoeboid motion of Dictyostelium discoideum cells.

Rappel, Wouter-Jan

2013-03-01

468

Present Status of the Theoretical Predictions for the 36Cl Solar-Neutrino Experiment  

Microsoft Academic Search

The theoretical predictions for the 37Cl solar-neutrino experiment are summarized and compared with the experimental results of Davis, Harmer, and Hoffman. Three important conclusions about the sun are shown to follow.

John N. Bahcall; Neta A. Bahcall; Giora Shaviv

1968-01-01

469

Solar Total Energy: Large Scale Experiment, Shenandoah, Georgia Site. Annual Report, June 1978-June 1979.  

National Technical Information Service (NTIS)

A background summary and a complete description of the progress and current status of activities relative to the Cooperative Agreement for the Solar Total Energy - Large Scale Experiment at the Bleyle Knitwear Plant at Shenandoah, Georgia are presented. A...

E. J. Ney

1979-01-01

470

Solar cells design for low and medium concentrating photovoltaic systems  

NASA Astrophysics Data System (ADS)

The solar cell is the key element of any CPV system, and its design plays an important role in enhancing the performance of the entire system. Special types of cells are required in the CPV systems capable of operating at high concentrations and elevated temperatures. These Concentrator solar cells differ significantly from the usual solar cells in the method of manufacture, the overall cell design and their performance. Systematic design and manufacture of the cell ensures better performance in a given CPV system. A number of factors come into play while designing the solar cell for a specific system these include concentration, cell material properties, expected operating temperature, shape, bus bar configuration and finger spacing. Most of these variables are decided on based on some rules of thumb and PC1D calculations. However, there is scope for design improvement and cell optimization by performing a detailed analysis based on the illumination profile incident on the cell. Recent studies demonstrated the use of Finite element method to analyze the electrical behavior of PV cell under the influence of arbitrarily chosen illumination flux profiles. This study outlines a methodology and analysis procedure while performing a case study of a CPV system under development having a non-uniform illumination profile towards the exit of the concentrator. The LCPV system chosen is the Photovoltaic Facades of Reduced Costs Incorporating Devices with Optically Concentrating Elements (PRIDE) concentrator made of dielectric material. A coupled optical, thermal and electrical analysis is performed on the system to demonstrate the method useful in designing solar cells for low and medium concentrations.

Baig, Hasan; Heasman, Keith C.; Sarmah, Nabin; Mallick, Tapas

2012-10-01

471

GAAS shallow-homojunction solar cells. Final report  

SciTech Connect

The feasibility of fabricating space resistant, high efficiency, light weight, low cost GaAs shallow homojunction solar cells for space application is investigated. The material preparation of ultrathin GaAs single crystal layers, and the fabrication of efficient GaAs solar cells on bulk GaAs substrates are discussed. Considerable progress was made in both areas, and conversion efficiency about 16% AMO was obtained using anodic oxide as a single layer antireflection coating. A computer design shows that even better cells can be obtained with double layer antireflection coating. Ultrathin, high efficiency solar cells were obtained from GaAs films prepared by the CLEFT process, with conversion efficiency as high as 17% at AMI from a 10 micrometers thick GaAs film. A organometallic CVD was designed and constructed.

Fan, J.C.C.

1981-06-01

472

Laminated photovoltaic modules using back-contact solar cells  

DOEpatents

Photovoltaic modules which comprise back-contact solar cells, such as back-contact crystalline silicon solar cells, positioned atop electrically conductive circuit elements affixed to a planar support so that a circuit capable of generating electric power is created. The modules are encapsulated using encapsulant materials such as EVA which are commonly used in photovoltaic module manufacture. The module designs allow multiple cells to be electrically connected in a single encapsulation step rather than by sequential soldering which characterizes the currently used commercial practices.

Gee, James M. (Albuquerque, NM); Garrett, Stephen E. (Albuquerque, NM); Morgan, William P. (Albuquerque, NM); Worobey, Walter (Albuquerque, NM)

1999-09-14

473

Electroless copper contacts for low concentration silicon solar cells  

NASA Astrophysics Data System (ADS)

The purpose of this work was to form highly conductive and low cost copper contacts on shallow and hence optically thin p-n junctions (<0.4?m deep) on a randomly textured solar cells for low concentration PV (LCPV) module. At first, window formation process in SiNx by femtosecond UV laser pulse ablation on the textured surface was introduced. Then nickel silicide contacts were formed and subsequent contact thickening was performed by electroless copper plating in an industrially feasible way. Characteristics of finished solar cells were investigated in this work. The cells were successfully implemented into the low concentration (C=15x) PV module.

Janušonis, Julius; Galdikas, Algirdas; Juzumas, Valdemaras; Jaramin?, Lina; Lukštaraupis, Tomas; Andrijauskas, Darius; Janušonien?, Vida; Janušonis, Darius; Ulbikas, Juras

2012-10-01

474

New developments in CIGS thin-film solar cell technology  

Microsoft Academic Search

Thin-film solar modules based on Cu(In,Ga)Se\\/sub 2\\/ (ClGS) are on the way to mass production. ZSW is operating a line for 0.3 m \\/spl times\\/ 0.3 m modules in which all process steps - from glass cleaning to module encapsulation - are being developed. Especially new materials and processes are transferred from cells to the module level. In Wuerth Solar's

Michael Powalla; B. Dimmler

2003-01-01

475

Integration of Microstrip Patch Antenna With Polycrystalline Silicon Solar Cell  

Microsoft Academic Search

The implementation of a polycrystalline silicon solar cell as a microwave groundplane in a low-profile, reduced-footprint microstrip patch antenna design for autonomous communication applications is reported. The effects on the antenna\\/solar performances due to the integration, different electrical conductivities in the silicon layer and variation in incident light intensity are investigated. The antenna sensitivity to the orientation of the anisotropic

S. V. Shynu; Maria Jose Roo Ons; Patrick McEvoy; Max J. Ammann; Sarah J. McCormack; Brian Norton

2009-01-01

476

Integration of Microstrip Patch Antennas with Polycrystalline Silicon Solar Cells  

Microsoft Academic Search

The implementation of a polycrystalline silicon solar cell as a microwave groundplane in a low-profile, reduced-footprint microstrip patch antenna design for autonomous communication applications is reported. The effects on the antenna\\/solar performances due to the integration, different electrical conductivities in the silicon layer and variation in incident light intensity are investigated. The antenna sensitivity to the orientation of the anisotropic

S. V. Shynu; M. Roo Ons; Max Ammann; Sarah McCormack; Brian Norton

2009-01-01

477

Silicon nanocrystals as light converter for solar cells  

Microsoft Academic Search

In this work, we investigate the potential use of silicon nanocrystals (Si-nc) into photovoltaics technology as one possible way to increase the silicon solar efficiency at low cost. The Si-nc were prepared ex situ (pulverizing of electrochemical etched porous silicon), embedded into spin-on-glass antireflecting SiO2 based solution and then spun onto standard silicon solar cells. The Si-nc\\/SiO2 layer serves as

V. Švr?ek; A. Slaoui; J.-C. Muller

2004-01-01

478

Characterization of CdSe Nanocrystals for Hybrid Solar Cells  

Microsoft Academic Search

Hybrid solar cells have attracted considerable attention in recent years due to their high thermal and chemical stability, light weight, high carrier mobility, and low cost. The active layer of cadmium selenide (CdSe) nanoparticles- poly(3-hexylthiophene) (P3HT) is optimized in terms of their mass ratio and microstructure by using absorption and scanning electron microscope (SEM). The active layer of hybrid solar

Virendra Kumar Verma; Yashvendra Singh; Ram Narayan Chauhan; R. S. Anand; Jitendra Kumar

2010-01-01

479

Nanostructured solar cells employ wide-band-gap  

Microsoft Academic Search

The solar-electric conversion efficiency of traditional semicon- ductor solar cells is limited by a fundamental trade-off between the current generated by photon absorption and the operating voltage. Photons with energies below the semiconductor band gap pass straight through the device and do not contribute to the photocurrent. High-energy photons can be absorbed, but the resulting electrons are collected and extracted

Roger Welser

480

High-efficiency space and terrestrial multijunction solar cells through bandgap control in cell structures  

Microsoft Academic Search

Using the energy bandgap of semiconductors as a design parameter is critically important for achieving the highest efficiency multijunction solar cells. The bandgaps of lattice-matched semiconductors that are most convenient to use are rarely those which would result in the highest theoretical efficiency. For both the space and terrestrial solar spectra, the efficiency of 3-junction GaInP\\/GaAs\\/Ge solar cells can be

Richard R. King; C. M. Fetzer; Peter C. Colter; Ken M. Edmondson; J. H. Ermer; Hector L. Cotal; Hojun Yoon; Alex P. Stavrides; Geoff Kinsey; Dimitri D. Krut; N. H. Karam

2002-01-01