Characterization of photovoltaic array performance: an overview

Energy Technology Data Exchange (ETDEWEB)

Ross, Jr., R. G.

1986-09-15

Characterization of the electrical performance of a photovoltaic array can take many forms depending on the end use of the data. Typical uses include buyer-seller negotiations, system performance prediction, and performance measurement. Buyer-seller negotiations may deal with specifying the size (power) of an array to be purchased under some standard reporting conditions, and may treat the warranty conditions governing allowable degradation of this performance with time. System design, on the other hand, requires prediction of performance under varying field conditions, not standard reporting conditions, and must include the non-ideal realities of operating systems: array shadowing, steep angles of incidence, soiling, and array-load energy utilization. Typical uses of predicted array performance include array sizing tradeoffs, tracking-pointing comparisons, load-array interface analyses and system economic evaluations. The third use, performance measurement, refers to the characterization of an as-built array as opposed to prediction of the performance of an array to be built. This may be done to assess actual array performance or to measure performance degradation over time.

Maximum power point tracking of partially shaded solar photovoltaic arrays

Energy Technology Data Exchange (ETDEWEB)

Roy Chowdhury, Shubhajit; Saha, Hiranmay [IC Design and Fabrication Centre, Department of Electronics and Telecommunication Engineering, Jadavpur University (India)

2010-09-15

The paper presents the simulation and hardware implementation of maximum power point (MPP) tracking of a partially shaded solar photovoltaic (PV) array using a variant of Particle Swarm Optimization known as Adaptive Perceptive Particle Swarm Optimization (APPSO). Under partially shaded conditions, the photovoltaic (PV) array characteristics get more complex with multiple maxima in the power-voltage characteristic. The paper presents an algorithmic technique to accurately track the maximum power point (MPP) of a PV array using an APPSO. The APPSO algorithm has also been validated in the current work. The proposed technique uses only one pair of sensors to control multiple PV arrays. This result in lower cost and higher accuracy of 97.7% compared to earlier obtained accuracy of 96.41% using Particle Swarm Optimization. The proposed tracking technique has been mapped onto a MSP430FG4618 microcontroller for tracking and control purposes. The whole system based on the proposed has been realized on a standard two stage power electronic system configuration. (author)

Design of photovoltaic central power station concentrator array

Energy Technology Data Exchange (ETDEWEB)

1984-02-01

A design for a photovoltaic central power station using tracking concentrators has been developed. The 100 MW plant is assumed to be located adjacent to the Saguaro Power Station of Arizona Public Service. The design assumes an advanced Martin Marietta two-axis tracking fresnel lens concentrator. The concentrators are arrayed in 5 MW subfields, each with its own power conditioning unit. The photovoltaic plant output is connected to the existing 115 kV switchyard. The site specific design allows detailed cost estimates for engineering, site preparation, and installation. Collector and power conditioning costs have been treated parametrically.

Design of a photovoltaic central power station: flat-plate array

Energy Technology Data Exchange (ETDEWEB)

1984-02-01

A design for a photovoltaic central power station using fixed flat-panel arrays has been developed. The 100 MW plant is assumed to be located adjacent to the Saguaro Power Station of Arizona Public Service. The design assumes high-efficiency photovoltaic modules using dendritic web cells. The modules are arranged in 5 MW subfields, each with its own power conditioning unit. The photovoltaic output is connected to the existing 115 kV utility switchyard. The site specific design allows detailed cost estimates for engineering, site preparation, and installation. Collector and power conditioning costs have been treated parametrically.

Wind loads on flat plate photovoltaic array fields

Science.gov (United States)

Miller, R. D.; Zimmerman, D. K.

1981-01-01

The results of an experimental analysis (boundary layer wind tunnel test) of the aerodynamic forces resulting from winds acting on flat plate photovoltaic arrays are presented. Local pressure coefficient distributions and normal force coefficients on the arrays are shown and compared to theoretical results. Parameters that were varied when determining the aerodynamic forces included tilt angle, array separation, ground clearance, protective wind barriers, and the effect of the wind velocity profile. Recommended design wind forces and pressures are presented, which envelop the test results for winds perpendicular to the array's longitudinal axis. This wind direction produces the maximum wind loads on the arrays except at the array edge where oblique winds produce larger edge pressure loads. The arrays located at the outer boundary of an array field have a protective influence on the interior arrays of the field. A significant decrease of the array wind loads were recorded in the wind tunnel test on array panels located behind a fence and/or interior to the array field compared to the arrays on the boundary and unprotected from the wind. The magnitude of this decrease was the same whether caused by a fence or upwind arrays.

Modeling impact of environmental factors on photovoltaic array performance

Energy Technology Data Exchange (ETDEWEB)

Yang, Jie; Sun, Yize; Xu, Yang [College of Mechanical Engineering, Donghua University NO.2999, North Renmin Road, Shanghai (China)

2013-07-01

It is represented in this paper that a methodology to model and quantify the impact of the three environmental factors, the ambient temperature, the incident irradiance and the wind speed, upon the performance of photovoltaic array operating under outdoor conditions. First, A simple correlation correlating operating temperature with the three environmental variables is validated for a range of wind speed studied, 2-8, and for irradiance values between 200 and 1000. Root mean square error (RMSE) between modeled operating temperature and measured values is 1.19% and the mean bias error (MBE) is -0.09%. The environmental factors studied influence I-V curves, P-V curves, and maximum-power outputs of photovoltaic array. The cell-to-module-to-array mathematical model for photovoltaic panels is established in this paper and the method defined as segmented iteration is adopted to solve the I-V curve expression to relate model I-V curves. The model I-V curves and P-V curves are concluded to coincide well with measured data points. The RMSE between numerically calculated maximum-power outputs and experimentally measured ones is 0.2307%, while the MBE is 0.0183%. In addition, a multivariable non-linear regression equation is proposed to eliminate the difference between numerically calculated values and measured ones of maximum power outputs over the range of high ambient temperature and irradiance at noon and in the early afternoon. In conclusion, the proposed method is reasonably simple and accurate.

Residential photovoltaic module and array requirement study. Low-Cost Solar Array Project engineering area. Final report appendices

Energy Technology Data Exchange (ETDEWEB)

1979-06-01

This volume contains the appendices to a study to identify design requirements for photovoltaic modules and arrays used in residential applications. Appendices include: (1) codes, standards, and manuals of accepted practice-definition and importance; (2) regional code variations-impact; (3) model and city codes-review; (4) National Electric Code (NEC)-review; (5) types of standards-definition and importance; (6) federal standards-review; (7) standards review method; (8) manuals of accepted practice; (9) codes and referenced standards-summary; (10) public safety testing laboratories; (11) insurance review; (12) studies approach; (13) mounting configurations; (14) module/panel size and shape cost analysis; (15) grounding, wiring, terminal and voltage studies; (16) array installation cost summary; (17) photovoltaic shingle/module comparison; (18) retrofit application; (19) residential photovoltaic module performance criteria; (20) critique of JPL's solar cell module design and test specifications for residential applications; and (21) CSI format specification. (WHK)

Preprinting Microbiology.

Science.gov (United States)

Schloss, Patrick D

2017-05-23

The field of microbiology has experienced significant growth due to transformative advances in technology and the influx of scientists driven by a curiosity to understand how microbes sustain myriad biochemical processes that maintain Earth. With this explosion in scientific output, a significant bottleneck has been the ability to rapidly disseminate new knowledge to peers and the public. Preprints have emerged as a tool that a growing number of microbiologists are using to overcome this bottleneck. Posting preprints can help to transparently recruit a more diverse pool of reviewers prior to submitting to a journal for formal peer review. Although the use of preprints is still limited in the biological sciences, early indications are that preprints are a robust tool that can complement and enhance peer-reviewed publications. As publishing moves to embrace advances in Internet technology, there are many opportunities for preprints and peer-reviewed journals to coexist in the same ecosystem. Copyright © 2017 Schloss.

Real Time Photovoltaic Array Simulator for Testing Grid-Connected PV Inverters

DEFF Research Database (Denmark)

Sera, Dezso; Valentini, Massimo; Raducu, Alin

2008-01-01

In this paper a real time flexible PV array simulator is presented. It is a system that can simulate different PV panel arrays in specific environmental conditions. To evaluate performance of the Maximum Power Point Tracking (MPPT) of grid-connected Photovoltaic (PV) inverters only measurements...... undertaken with an appropriate PV array simulator provide accurate and reproducible results. Thus the PV array simulator has been developed and implemented. MPPT efficiency tests on a commercial grid-connected PV inverter have been performed to validate the PV array simulator....

Broadband absorption of semiconductor nanowire arrays for photovoltaic applications

International Nuclear Information System (INIS)

Huang, Ningfeng; Lin, Chenxi; Povinelli, Michelle L

2012-01-01

We use electromagnetic simulations to carry out a systematic study of broadband absorption in vertically-aligned semiconductor nanowire arrays for photovoltaic applications. We study six semiconductor materials that are commonly used for solar cells. We optimize the structural parameters of each nanowire array to maximize the ultimate efficiency. We plot the maximal ultimate efficiency as a function of height to determine how it approaches the perfect-absorption limit. We further show that the ultimate efficiencies of optimized nanowire arrays exceed those of equal-height thin films for all six materials and over a wide range of heights from 100 nm to 100 µm

Plasmonic Photovoltaic Cells with Dual-Functional Gold, Silver, and Copper Half-Shell Arrays.

Science.gov (United States)

Wu, Ling; Kim, Gyu Min; Nishi, Hiroyasu; Tatsuma, Tetsu

2017-09-12

Solid-state photovoltaic cells based on plasmon-induced charge separation (PICS) have attracted growing attention during the past decade. However, the power conversion efficiency (PCE) of the previously reported devices, which are generally loaded with dispersed metal nanoparticles as light absorbers, has not been sufficiently high. Here we report simpler plasmonic photovoltaic cells with interconnected Au, Ag, and Cu half-shell arrays deposited on SiO 2 @TiO 2 colloidal crystals, which serve both as a plasmonic light absorber and as a current collector. The well-controlled and easily prepared plasmonic structure allows precise comparison of the PICS efficiency between different plasmonic metal species. The cell with the Ag half-shell array has higher photovoltaic performance than the cells with Au and Cu half-shell arrays because of the high population of photogenerated energetic electrons, which gives a high electron injection efficiency and suppressed charge recombination probability, achieving the highest PCE among the solid-state PICS devices even without a hole transport layer.

High-Speed Monitoring of Multiple Grid-Connected Photovoltaic Array Configurations and Supplementary Weather Station.

Science.gov (United States)

Boyd, Matthew T

2017-06-01

Three grid-connected monocrystalline silicon photovoltaic arrays have been instrumented with research-grade sensors on the Gaithersburg, MD campus of the National Institute of Standards and Technology (NIST). These arrays range from 73 kW to 271 kW and have different tilts, orientations, and configurations. Irradiance, temperature, wind, and electrical measurements at the arrays are recorded, and images are taken of the arrays to monitor shading and capture any anomalies. A weather station has also been constructed that includes research-grade instrumentation to measure all standard meteorological quantities plus additional solar irradiance spectral bands, full spectrum curves, and directional components using multiple irradiance sensor technologies. Reference photovoltaic (PV) modules are also monitored to provide comprehensive baseline measurements for the PV arrays. Images of the whole sky are captured, along with images of the instrumentation and reference modules to document any obstructions or anomalies. Nearly, all measurements at the arrays and weather station are sampled and saved every 1s, with monitoring having started on Aug. 1, 2014. This report describes the instrumentation approach used to monitor the performance of these photovoltaic systems, measure the meteorological quantities, and acquire the images for use in PV performance and weather monitoring and computer model validation.

The optimal configuration of photovoltaic module arrays based on adaptive switching controls

International Nuclear Information System (INIS)

Chao, Kuei-Hsiang; Lai, Pei-Lun; Liao, Bo-Jyun

2015-01-01

Highlights: • We propose a strategy for determining the optimal configuration of a PV array. • The proposed strategy was based on particle swarm optimization (PSO) method. • It can identify the optimal module array connection scheme in the event of shading. • It can also find the optimal connection of a PV array even in module malfunctions. - Abstract: This study proposes a strategy for determining the optimal configuration of photovoltaic (PV) module arrays in shading or malfunction conditions. This strategy was based on particle swarm optimization (PSO). If shading or malfunctions of the photovoltaic module array occur, the module array immediately undergoes adaptive reconfiguration to increase the power output of the PV power generation system. First, the maximal power generated at various irradiation levels and temperatures was recorded during normal array operation. Subsequently, the irradiation level and module temperature, regardless of operating conditions, were used to recall the maximal power previously recorded. This previous maximum was compared with the maximal power value obtained using the maximum power point tracker to assess whether the PV module array was experiencing shading or malfunctions. After determining that the array was experiencing shading or malfunctions, PSO was used to identify the optimal module array connection scheme in abnormal conditions, and connection switches were used to implement optimal array reconfiguration. Finally, experiments were conducted to assess the strategy for identifying the optimal reconfiguration of a PV module array in the event of shading or malfunctions

Performance of solar photovoltaic array fed water pumping system ...

African Journals Online (AJOL)

This paper discusses the design and performance analysis of a solar photovoltaic (SPV) array fed water pumping system utilizing a special class of highly rugged machine with simple drive system called switched reluctance motor (SRM) drive. The proposed method of water pumping system also provides the cost effective ...

Output Performance and Payback Analysis of a Residential Photovoltaic System in Colorado: Preprint

Energy Technology Data Exchange (ETDEWEB)

Johnston, S.

2012-06-01

Cost of installation and ownership of a 9.66-kilowatt (kW) residential photovoltaic system is described, and the performance of this system over the past 3 years is shown. The system is located in Colorado at 40 degrees latitude and consists of arrays on two structures. Two arrays are installed on a detached garage, and these are each composed of 18 Kyocera 130-W modules strung in series facing south at an angle of 40 degrees above horizontal. Each 18-panel array feeds into a Xantrex/Schneider Electric 2.8-kW inverter. The other two arrays are installed on the house and face south at an angle of 30 degrees. One of these arrays has twelve 205-W Kyocera panels in series, and the other is made up of twelve 210-Kyocera panels. Each of these arrays feeds into Xantrex/Schneider Electric 3.3-kW inverters. Although there are various shading issues from trees and utility poles and lines, the overall output resembles that which is expected from PVWatts, a solar estimate program. The array cost, which was offset by rebates from the utility company and federal tax credits, was $1.17 per watt. Considering measured system performance, the estimated payback time of the system is 9 years.

PVSIM{copyright}: A simulation program for photovoltaic cells, modules, and arrays

Energy Technology Data Exchange (ETDEWEB)

King, D.L.; Dudley, J.K.; Boyson, W.E.

1996-06-01

An electrical simulation model for photovoltaic cells, modules, and arrays has been developed that will be useful to a wide range of analysts in the photovoltaic industry. The Microsoft{reg_sign} Windows{trademark} based program can be used to analyze individual cells, to analyze the effects of cell mismatch or reverse bias(`hot spot`) heating in modules and to analyze the performance of large arrays of modules including bypass and blocking diodes. User defined statistical variance can be applied to the fundamental parameters used to simulate the cells and diodes. The model is most appropriate for cells that can be accurately modeled using a two-diode equivalent circuit. This paper describes the simulation program and illustrates its versatility with examples.

Design considerations for large roof-integrated photovoltaic arrays

Energy Technology Data Exchange (ETDEWEB)

Ropp, M.E.; Begovic, M.; Rohatgi, A. [Georgia Inst. of Tech., Atlanta, GA (United States); Long, R. [Georgia Institute of Technology, Atlanta (United States). Office of Facilities

1997-01-01

This paper describes calculations and modeling used in the design of the photovoltaic (PV) array built on the roof of the Georgia Tech Aquatic Center, the aquatic sports venue for the 1996 Olympic and Paralympic Games. The software package PVFORM (version 3.3) was extensively utilized; because of its importance to this work, it is thoroughly reviewed here. Procedures required to adapt PVFORM to this particular installation are described. The expected behavior and performance of the system, including maximum power output, annual energy output and maximum expected temperature, are then presented, and the use of this information in making informed design decisions is described. Finally, since the orientation of the PV array is not optimal, the effect of the unoptimized array orientation on the system`s performance is quantified. (author)

Assessment of low-cost manufacturing process sequences. [photovoltaic solar arrays

Science.gov (United States)

Chamberlain, R. G.

1979-01-01

An extensive research and development activity to reduce the cost of manufacturing photovoltaic solar arrays by a factor of approximately one hundred is discussed. Proposed and actual manufacturing process descriptions were compared to manufacturing costs. An overview of this methodology is presented.

Characterization of the electrical output of flat-plate photovoltaic arrays

Science.gov (United States)

Gonzalez, C. C.; Hill, G. M.; Ross, R. G., Jr.

1982-01-01

The electric output of flat-plate photovoltaic arrays changes constantly, due primarily to changes in cell temperature and irradiance level. As a result, array loads such as direct-current to alternating-current power conditioners must be able to accommodate widely varying input levels, while maintaining operation at or near the array maximum power point.The results of an extensive computer simulation study that was used to define the parameters necessary for the systematic design of array/power-conditioner interfaces are presented as normalized ratios of power-conditioner parameters to array parameters, to make the results universally applicable to a wide variety of system sizes, sites, and operating modes. The advantages of maximum power tracking and a technique for computing average annual power-conditioner efficiency are discussed.

Fault Analysis in Solar Photovoltaic Arrays

Science.gov (United States)

Zhao, Ye

Fault analysis in solar photovoltaic (PV) arrays is a fundamental task to increase reliability, efficiency and safety in PV systems. Conventional fault protection methods usually add fuses or circuit breakers in series with PV components. But these protection devices are only able to clear faults and isolate faulty circuits if they carry a large fault current. However, this research shows that faults in PV arrays may not be cleared by fuses under some fault scenarios, due to the current-limiting nature and non-linear output characteristics of PV arrays. First, this thesis introduces new simulation and analytic models that are suitable for fault analysis in PV arrays. Based on the simulation environment, this thesis studies a variety of typical faults in PV arrays, such as ground faults, line-line faults, and mismatch faults. The effect of a maximum power point tracker on fault current is discussed and shown to, at times, prevent the fault current protection devices to trip. A small-scale experimental PV benchmark system has been developed in Northeastern University to further validate the simulation conclusions. Additionally, this thesis examines two types of unique faults found in a PV array that have not been studied in the literature. One is a fault that occurs under low irradiance condition. The other is a fault evolution in a PV array during night-to-day transition. Our simulation and experimental results show that overcurrent protection devices are unable to clear the fault under "low irradiance" and "night-to-day transition". However, the overcurrent protection devices may work properly when the same PV fault occurs in daylight. As a result, a fault under "low irradiance" and "night-to-day transition" might be hidden in the PV array and become a potential hazard for system efficiency and reliability.

Smart Global Maximum Power Point Tracking Controller of Photovoltaic Module Arrays

Directory of Open Access Journals (Sweden)

Long-Yi Chang

2018-03-01

Full Text Available This study first explored the effect of shading on the output characteristics of modules in a photovoltaic module array. Next, a modified particle swarm optimization (PSO method was employed to track the maximum power point of the multiple-peak characteristic curve of the array. Through the optimization method, the weighting value and cognition learning factor decreased with an increasing number of iterations, whereas the social learning factor increased, thereby enhancing the tracking capability of a maximum power point tracker. In addition, the weighting value was slightly modified on the basis of the changes in the slope and power of the characteristic curve to increase the tracking speed and stability of the tracker. Finally, a PIC18F8720 microcontroller was coordinated with peripheral hardware circuits to realize the proposed PSO method, which was then adopted to track the maximum power point of the power–voltage (P–V output characteristic curve of the photovoltaic module array under shading. Subsequently, tests were conducted to verify that the modified PSO method exhibited favorable tracking speed and accuracy.

Regional climate consequences of large-scale cool roof and photovoltaic array deployment

International Nuclear Information System (INIS)

Millstein, Dev; Menon, Surabi

2011-01-01

Modifications to the surface albedo through the deployment of cool roofs and pavements (reflective materials) and photovoltaic arrays (low reflection) have the potential to change radiative forcing, surface temperatures, and regional weather patterns. In this work we investigate the regional climate and radiative effects of modifying surface albedo to mimic massive deployment of cool surfaces (roofs and pavements) and, separately, photovoltaic arrays across the United States. We use a fully coupled regional climate model, the Weather Research and Forecasting (WRF) model, to investigate feedbacks between surface albedo changes, surface temperature, precipitation and average cloud cover. With the adoption of cool roofs and pavements, domain-wide annual average outgoing radiation increased by 0.16 ± 0.03 W m -2 (mean ± 95% C.I.) and afternoon summertime temperature in urban locations was reduced by 0.11-0.53 deg. C, although some urban areas showed no statistically significant temperature changes. In response to increased urban albedo, some rural locations showed summer afternoon temperature increases of up to + 0.27 deg. C and these regions were correlated with less cloud cover and lower precipitation. The emissions offset obtained by this increase in outgoing radiation is calculated to be 3.3 ± 0.5 Gt CO 2 (mean ± 95% C.I.). The hypothetical solar arrays were designed to be able to produce one terawatt of peak energy and were located in the Mojave Desert of California. To simulate the arrays, the desert surface albedo was darkened, causing local afternoon temperature increases of up to + 0.4 deg. C. Due to the solar arrays, local and regional wind patterns within a 300 km radius were affected. Statistically significant but lower magnitude changes to temperature and radiation could be seen across the domain due to the introduction of the solar arrays. The addition of photovoltaic arrays caused no significant change to summertime outgoing radiation when averaged

Effects of design on cost of flat-plate solar photovoltaic arrays for terrestrial central station power applications

Science.gov (United States)

Tsou, P.; Stolte, W.

1978-01-01

The paper examines the impact of module and array designs on the balance-of-plant costs for flat-plate terrestrial central station power applications. Consideration is given to the following types of arrays: horizontal, tandem, augmented, tilt adjusted, and E-W tracking. The life-cycle cost of a 20-year plant life serves as the costing criteria for making design and cost tradeoffs. A tailored code of accounts is developed for determining consistent photovoltaic power plant costs and providing credible photovoltaic system cost baselines for flat-plate module and array designs by costing several varying array design approaches.

SIMULATION OF NEW SIMPLE FUZZY LOGIC MAXIMUM POWER POINT TRACKER FOR PHOTOVOLTAIC ARRAY

Directory of Open Access Journals (Sweden)

H. Serhoud

2015-08-01

Full Text Available A new simple fuzzy method used for tracking the maximum power point tracker (MPPT for photovoltaic systems is proposed. The input parameters   and duty cycle D are used to generate the optimal MPPT under different operating conditions, The photovoltaic system simulated and constructed by photovoltaic arrays, a DC/DC boost converter, a fuzzy MPPT control and a resistive load, The Fuzzy control law designed and the results in a simulation platform will be presented and compare to Perturbation and observation (P&O controller.

search.bioPreprint: a discovery tool for cutting edge, preprint biomedical research articles [version 2; referees: 2 approved

Directory of Open Access Journals (Sweden)

Carrie L. Iwema

2016-07-01

Full Text Available The time it takes for a completed manuscript to be published traditionally can be extremely lengthy. Article publication delay, which occurs in part due to constraints associated with peer review, can prevent the timely dissemination of critical and actionable data associated with new information on rare diseases or developing health concerns such as Zika virus. Preprint servers are open access online repositories housing preprint research articles that enable authors (1 to make their research immediately and freely available and (2 to receive commentary and peer review prior to journal submission. There is a growing movement of preprint advocates aiming to change the current journal publication and peer review system, proposing that preprints catalyze biomedical discovery, support career advancement, and improve scientific communication. While the number of articles submitted to and hosted by preprint servers are gradually increasing, there has been no simple way to identify biomedical research published in a preprint format, as they are not typically indexed and are only discoverable by directly searching the specific preprint server websites. To address this issue, we created a search engine that quickly compiles preprints from disparate host repositories and provides a one-stop search solution. Additionally, we developed a web application that bolsters the discovery of preprints by enabling each and every word or phrase appearing on any web site to be integrated with articles from preprint servers. This tool, search.bioPreprint, is publicly available at http://www.hsls.pitt.edu/resources/preprint.

Nonimaging concentrators for photovoltaic arrays in space

Science.gov (United States)

Winston, R.; Greenman, P.; Rockey, D.

1981-01-01

Two stage concentrators are studied in order to design an optimum concentrator for photovoltaic arrays in space. The study is directed at designs with two-dimensional geometries because they are better suited to moderate concentrations of about 10 X to 50 X, and because the instantaneous flux distribution is more uniform. It is found that with an f/0.5 primary, where f is the focal length of the primary, the flux distribution is very smooth regardless of the angle of incidence of the radiation. As the focal ratio is increased, peaks in the distribution begin to appear. The nonuniformities can be reduced by introducing small, closely spaced distortions into the reflecting surfaces, and practical arrays can achieve a concentration of 10 when the acceptance half angle is 4.25 deg or 50 when the acceptance half angle is + or - 1 deg.

Standard Test Methods for Electrical Performance of Nonconcentrator Terrestrial Photovoltaic Modules and Arrays Using Reference Cells

CERN Document Server

American Society for Testing and Materials. Philadelphia

2008-01-01

1.1 These test methods cover the electrical performance of photovoltaic modules and arrays under natural or simulated sunlight using a calibrated reference cell. 1.1.1 These test methods allow a reference module to be used instead of a reference cell provided the reference module has been calibrated using these test methods against a calibrated reference cell. 1.2 Measurements under a variety of conditions are allowed; results are reported under a select set of reporting conditions (RC) to facilitate comparison of results. 1.3 These test methods apply only to nonconcentrator terrestrial modules and arrays. 1.4 The performance parameters determined by these test methods apply only at the time of the test, and imply no past or future performance level. 1.5 These test methods apply to photovoltaic modules and arrays that do not contain series-connected photovoltaic multijunction devices; such module and arrays should be tested according to Test Methods E 2236. 1.6 The values stated in SI units are to be re...

Wind loads on flat plate photovoltaic array fields (nonsteady winds)

Science.gov (United States)

Miller, R. D.; Zimmerman, D. K.

1981-01-01

Techniques to predict the dynamic response and the structural dynamic loads of flat plate photovoltaic arrays due to wind turbulence were analyzed. Guidelines for use in predicting the turbulent portion of the wind loading on future similar arrays are presented. The dynamic response and the loads dynamic magnification factor of the two array configurations are similar. The magnification factors at a mid chord and outer chord location on the array illustrated and at four points on the chord are shown. The wind tunnel test experimental rms pressure coefficient on which magnification factors are based is shown. It is found that the largest response and dynamic magnification factor occur at a mid chord location on an array and near the trailing edge. A technique employing these magnification factors and the wind tunnel test rms fluctuating pressure coefficients to calculate design pressure loads due to wind turbulence is presented.

Photovoltaic array for Martian surface power

Science.gov (United States)

Appelbaum, J.; Landis, G. A.

1992-01-01

Missions to Mars will require electric power. A leading candidate for providing power is solar power produced by photovoltaic arrays. To design such a power system, detailed information on solar-radiation availability on the Martian surface is necessary. The variation of the solar radiation on the Martian surface is governed by three factors: (1) variation in Mars-Sun distance; (2) variation in solar zenith angle due to Martian season and time of day; and (3) dust in the Martian atmosphere. A major concern is the dust storms, which occur on both local and global scales. However, there is still appreciable diffuse sunlight available even at high opacity, so that solar array operation is still possible. Typical results for tracking solar collectors are also shown and compared to the fixed collectors. During the Northern Hemisphere spring and summer the isolation is relatively high, 2-5 kW-hr/sq m-day, due to the low optical depth of the Martian atmosphere. These seasons, totalling a full terrestrial year, are the likely ones during which manned mission will be carried out.

Characterization and Diagnostics for Photovoltaic Modules and Arrays

DEFF Research Database (Denmark)

Spataru, Sergiu

part of this work were developed based on two well-known module characterization techniques, namely current-voltage (I-V) characterization, and electroluminescence imaging. he I-V based module diagnostic methods were developed by combining the strengths of light I-V and dark I-V characterization......, characterization and diagnostic methods are increasingly important in identifying and understanding the failures and degradation modes affecting PV modules and arrays, as well as developing relevant tools and tests for assessing the reliability and lifetime of PV modules. This thesis investigates diagnostic...... methods for characterizing and detecting degradation modes in crystalline silicon photovoltaic modules and arrays, and is structured into two parts. The first part of this work is focused on developing PV module characterization and diagnostic methods for use in module diagnostics and failure...

Multijunction Photovoltaic Technologies for High-Performance Concentrators: Preprint

Energy Technology Data Exchange (ETDEWEB)

McConnell, R.; Symko-Davies, M.

2006-05-01

Multijunction solar cells provide high-performance technology pathways leading to potentially low-cost electricity generated from concentrated sunlight. The National Center for Photovoltaics at the National Renewable Energy Laboratory has funded different III-V multijunction solar cell technologies and various solar concentration approaches. Within this group of projects, III-V solar cell efficiencies of 41% are close at hand and will likely be reported in these conference proceedings. Companies with well-developed solar concentrator structures foresee installed system costs of $3/watt--half of today's costs--within the next 2 to 5 years as these high-efficiency photovoltaic technologies are incorporated into their concentrator photovoltaic systems. These technology improvements are timely as new large-scale multi-megawatt markets, appropriate for high performance PV concentrators, open around the world.

Photovoltaic array sizing for Yemeni electrical needs

Energy Technology Data Exchange (ETDEWEB)

Al-Motawakel, M K; McVeigh, J C; Probert, S D; Norton, B

1986-10-01

A behavioural model has been developed for correlating the area of the solar array, the capacity of the storage batteries, and the system cost of a roof-top or centralized solar-energy system relative to the average daily electricity demand. The mathematical analysis incorporates pertinent social, economic, climatic and energy-resource factors. The model is employed to predict the average daily electrical needs for any one of the ten common energy uses currently occurring in Yemeni houses, reviews these needs in terms of the available solar energy systems, selects the relevant system components, and suggests the most cost-effective appropriate design of solar photovoltaic system.

Preprint data base system at INS: INSPREP system

International Nuclear Information System (INIS)

Shinohara, M.; Ukai, K.; Fujiyoshi, N.

1988-02-01

The library at the INS (Institute for Nuclear Study) receives several tens of preprints a week from foreign and domestic laboratories and universities. These preprints are pigeonholed by making a catalog card index carried a title, authors, an accession number, classification of fields, etc. A newly arrived preprint lists is also served every week. The cataloging and weekly lists publishing works were handled with a typewriter. And then, it was very difficult and tedious to correct/check/file the index cards and to correct/check the weekly preprint lists. To make a preprint data efficiently by a computer and to refer this data base by on-line without using a index card, the INSPREP system is constructed. The INSPREP system consists of two parts. One is named a PREPINS, and is used to make a preprint data, builds a preprint data base, and publishes a weekly preprint lists. The other, called a PREP, performs an on-line retrieval for this data base. The preprint data base consists of following items such as an author, a title, an accession number, a report number, a classification field, etc. The PREPINS can be used by limited persons for security. User can search a preprint by inputting above mentioned items. The PREP adopts a menu method. Then, user can perform an on-line retrieval very easily. (author)

A Procedure for Modeling Photovoltaic Arrays under Any Configuration and Shading Conditions

Directory of Open Access Journals (Sweden)

Daniel Gonzalez Montoya

2018-03-01

Full Text Available Photovoltaic (PV arrays can be connected following regular or irregular connection patterns to form regular configurations (e.g., series-parallel, total cross-tied, bridge-linked, etc. or irregular configurations, respectively. Several reported works propose models for a single configuration; hence, making the evaluation of arrays with different configuration is a considerable time-consuming task. Moreover, if the PV array adopts an irregular configuration, the classical models cannot be used for its analysis. This paper proposes a modeling procedure for PV arrays connected in any configuration and operating under uniform or partial shading conditions. The procedure divides the array into smaller arrays, named sub-arrays, which can be independently solved. The modeling procedure selects the mesh current solution or the node voltage solution depending on the topology of each sub-array. Therefore, the proposed approach analyzes the PV array using the least number of nonlinear equations. The proposed solution is validated through simulation and experimental results, which demonstrate the proposed model capacity to reproduce the electrical behavior of PV arrays connected in any configuration.

Ultradense, Deep Subwavelength Nanowire Array Photovoltaics As Engineered Optical Thin Films

KAUST Repository

Tham, Douglas

2010-11-10

A photovoltaic device comprised of an array of 20 nm wide, 32 nm pitch array of silicon nanowires is modeled as an optical material. The nanowire array (NWA) has characteristic device features that are deep in the subwavelength regime for light, which permits a number of simplifying approximations. Using photocurrent measurements as a probe of the absorptance, we show that the NWA optical properties can be accurately modeled with rigorous coupled-wave analysis. The densely structured NWAs behave as homogeneous birefringent materials into the ultraviolet with effective optical properties that are accurately modeled using the dielectric functions of bulk Si and SiO 2, coupled with a physical model for the NWA derived from ellipsometry and transmission electron microscopy. © 2010 American Chemical Society.

Electricity from photovoltaic solar cells. Flat-Plate Solar Array Project of the US Department of Energy's National Photovoltaics Program: 10 years of progress

Science.gov (United States)

Christensen, Elmer

1985-01-01

The objectives were to develop the flat-plate photovoltaic (PV) array technologies required for large-scale terrestrial use late in the 1980s and in the 1990s; advance crystalline silicon PV technologies; develop the technologies required to convert thin-film PV research results into viable module and array technology; and to stimulate transfer of knowledge of advanced PV materials, solar cells, modules, and arrays to the PV community. Progress reached on attaining these goals, along with future recommendations are discussed.

Photovoltaic Performance of a Nanowire/Quantum Dot Hybrid Nanostructure Array Solar Cell.

Science.gov (United States)

Wu, Yao; Yan, Xin; Zhang, Xia; Ren, Xiaomin

2018-02-23

An innovative solar cell based on a nanowire/quantum dot hybrid nanostructure array is designed and analyzed. By growing multilayer InAs quantum dots on the sidewalls of GaAs nanowires, not only the absorption spectrum of GaAs nanowires is extended by quantum dots but also the light absorption of quantum dots is dramatically enhanced due to the light-trapping effect of the nanowire array. By incorporating five layers of InAs quantum dots into a 500-nm high-GaAs nanowire array, the power conversion efficiency enhancement induced by the quantum dots is six times higher than the power conversion efficiency enhancement in thin-film solar cells which contain the same amount of quantum dots, indicating that the nanowire array structure can benefit the photovoltaic performance of quantum dot solar cells.

Enhancing transformer dynamic rating through grid application of photovoltaic arrays

International Nuclear Information System (INIS)

El-Gasseir, M.M.; Sayer, M.A.; Alteneder, K.P.; McCulla, G.A.; Bigger, J.

1993-01-01

This paper demonstrates that exact matching between the substation's peak-day load profile and the profile of coincident net output generation of the PV array is unjustifiable and will unduly lead to overlooking many investment deferment opportunities that would otherwise be major components of high value applications of PV arrays. Further, the paper shows how and to what extent the load matchability requirement could be relaxed. Because of the thermal inertia of transformers, the output of an adequately sized and located photovoltaic array can both delay and reduce transformer temperature rise even in cases where load peak occurs after sunset. The time lag due to thermal inertia and ambient temperature decline allow overloading of the transformer beyond its normal rating without significant loss of life. Simulations depicting the interplay between PV array capacity, ambient temperature, transformer size, oil and winding temperature rise, peak load magnitude, load profile and loss of life, have been conducted. Tradeoffs between PV array capacity and transformer over-rating gains have been assessed. The impacts of PV generation on the over-rating potential of an actual 22.4-MVA bank transformer of a Salt River Project (SRP) distribution substation in Phoenix, Arizona were evaluated

Organic photovoltaic cells with pentacene nanocolumn arrays

Energy Technology Data Exchange (ETDEWEB)

Yu, Shuwen; Schaefer, Peter; Rabe, Juergen P.; Koch, Norbert [Institut fuer Physik, Humboldt-Universitaet zu Berlin, Brook-Taylor-Str. 6, 12489 Berlin (Germany)

2011-07-01

Highly ordered pentacene nanocolumn arrays were fabricated by glancing angle deposition (GLAD) on indium tin oxide (ITO) substrates. The nanocolumn diameter was set to 100-150 nm as revealed by scanning electron microscopy and atomic force microscopy. Interdigitated bulk heterojunction photovoltaic cells (OPVCs) were formed by spin-coating [6,6]-phenyl-C{sub 61}-butyric acid methyl ester (PCBM) as the acceptor material onto the pentacene nanocolumn film. Bathocuproine (BCP) was deposited on top of PCBM as exciton blocking layer. The conversion efficiency of nanocolumn-based OPVCs was significantly higher compared to planar heterojunction OPVCs of the same materials. Further device performance improvement was achieved through employing a thin pentacene seed layer before GLAD, which promoted PCBM solution infiltration between pentacene nanocolumns.

Proceedings of the Flat-Plate Solar Array Project Research Forum on the Design of Flat-Plate Photovoltaic Arrays for Central Stations

Science.gov (United States)

1983-01-01

The Flat Plate Solar Array Project, focuses on advancing technologies relevant to the design and construction of megawatt level central station systems. Photovoltaic modules and arrays for flat plate central station or other large scale electric power production facilities require the establishment of a technical base that resolves design issues and results in practical and cost effective configurations. Design, qualification and maintenance issues related to central station arrays derived from the engineering and operating experiences of early applications and parallel laboratory reserch activities are investigated. Technical issues are examined from the viewpoint of the utility engineer, architect/engineer and laboratory researcher. Topics on optimum source circuit designs, module insulation design for high system voltages, array safety, structural interface design, measurements, and array operation and maintenance are discussed.

Space satellite power system. [conversion of solar energy by photovoltaic solar cell arrays

Science.gov (United States)

Glaser, P. E.

1974-01-01

The concept of a satellite solar power station was studied. It is shown that it offers the potential to meet a significant portion of future energy needs, is pollution free, and is sparing of irreplaceable earth resources. Solar energy is converted by photovoltaic solar cell arrays to dc energy which in turn is converted into microwave energy in a large active phased array. The microwave energy is beamed to earth with little attenuation and is converted back to dc energy on the earth. Economic factors are considered.

The preprint debate: What are the issues?

Science.gov (United States)

da Silva, Jaime A Teixeira

2018-04-01

The debate surrounding preprints is increasing. Preprint proponents claim that preprints are a way to shore up trust in academic publishing, that they provide an additional 'quality' screen prior to traditional peer review, that they can assist with the replication crisis plaguing science in part by making negative or contradictory results public, and that they speed up the publishing process because fundamental results can be presented early, serving as timely reports for the purposes of tenure or grant funding. Preprint skeptics and critics claim that preprints may represent a risk and a danger to quality-based academic publishing because they are documents that have not been carefully and thoroughly vetted prior to their release into the public domain. Thus, academics who cite invalid, poorly vetted, or false facts could cause harm, not unlike the unscholarly 'predatory' open access movement. Feedback on work from lesser-known groups, or on less glamorous topics, may be null or worse than from traditional peer review, annulling an initial key objective of preprints. Although there is no widespread empirical evidence or data yet regarding some of these issues, academics should be aware of the ideological, financial, and political tug-of-war taking place before deciding if they wish to publish their important findings as a preprint prior or simultaneous to submitting to a regular journal for peer review.

Proceedings of the Flat-Plate Solar Array Project Research Forum on Photovoltaic Metallization Systems

Science.gov (United States)

1983-01-01

A photovoltaic Metallization Research forum, under the sponsorship of the Flat-Plate Solar Array Project consisted of five sessions, covering: (1) the current status of metallization systems, (2) system design, (3) thick-film metallization, (4) advanced techniques, and (5) future metallization challenges.

Low-cost modular array-field designs for flat-panel and concentrator photovoltaic systems

Science.gov (United States)

Post, H. N.; Carmichael, D. C.; Alexander, G.; Castle, J. A.

1982-09-01

Described are the design and development of low-cost, modular array fields for flat-panel and concentrator photovoltaic (PV) systems. The objective of the work was to reduce substantially the cost of the array-field Balance-of-System (BOS) subsystems and site-specific design costs as compared to previous PV installations. These subsystems include site preparation, foundations, support structures, electrical writing, grounding, lightning protection, electromagnetic interference considerations, and controls. To reduce these BOS and design costs, standardized modular (building-block) designs for flat-panel and concentrator array fields have been developed that are fully integrated and optimized for lowest life-cycle costs. Using drawings and specifications now available, these building-block designs can be used in multiples to install various size array fields. The developed designs are immediately applicable (1982) and reduce the array-field BOS costs to a fraction of previous costs.

A Systematic Method of Interconnection Optimization for Dense-Array Concentrator Photovoltaic System

Science.gov (United States)

Siaw, Fei-Lu

2013-01-01

This paper presents a new systematic approach to analyze all possible array configurations in order to determine the most optimal dense-array configuration for concentrator photovoltaic (CPV) systems. The proposed method is fast, simple, reasonably accurate, and very useful as a preliminary study before constructing a dense-array CPV panel. Using measured flux distribution data, each CPV cells' voltage and current values at three critical points which are at short-circuit, open-circuit, and maximum power point are determined. From there, an algorithm groups the cells into basic modules. The next step is I-V curve prediction, to find the maximum output power of each array configuration. As a case study, twenty different I-V predictions are made for a prototype of nonimaging planar concentrator, and the array configuration that yields the highest output power is determined. The result is then verified by assembling and testing of an actual dense-array on the prototype. It was found that the I-V curve closely resembles simulated I-V prediction, and measured maximum output power varies by only 1.34%. PMID:24453823

A Systematic Method of Interconnection Optimization for Dense-Array Concentrator Photovoltaic System

Directory of Open Access Journals (Sweden)

Fei-Lu Siaw

2013-01-01

Full Text Available This paper presents a new systematic approach to analyze all possible array configurations in order to determine the most optimal dense-array configuration for concentrator photovoltaic (CPV systems. The proposed method is fast, simple, reasonably accurate, and very useful as a preliminary study before constructing a dense-array CPV panel. Using measured flux distribution data, each CPV cells’ voltage and current values at three critical points which are at short-circuit, open-circuit, and maximum power point are determined. From there, an algorithm groups the cells into basic modules. The next step is I-V curve prediction, to find the maximum output power of each array configuration. As a case study, twenty different I-V predictions are made for a prototype of nonimaging planar concentrator, and the array configuration that yields the highest output power is determined. The result is then verified by assembling and testing of an actual dense-array on the prototype. It was found that the I-V curve closely resembles simulated I-V prediction, and measured maximum output power varies by only 1.34%.

A systematic method of interconnection optimization for dense-array concentrator photovoltaic system.

Science.gov (United States)

Siaw, Fei-Lu; Chong, Kok-Keong

2013-01-01

This paper presents a new systematic approach to analyze all possible array configurations in order to determine the most optimal dense-array configuration for concentrator photovoltaic (CPV) systems. The proposed method is fast, simple, reasonably accurate, and very useful as a preliminary study before constructing a dense-array CPV panel. Using measured flux distribution data, each CPV cells' voltage and current values at three critical points which are at short-circuit, open-circuit, and maximum power point are determined. From there, an algorithm groups the cells into basic modules. The next step is I-V curve prediction, to find the maximum output power of each array configuration. As a case study, twenty different I-V predictions are made for a prototype of nonimaging planar concentrator, and the array configuration that yields the highest output power is determined. The result is then verified by assembling and testing of an actual dense-array on the prototype. It was found that the I-V curve closely resembles simulated I-V prediction, and measured maximum output power varies by only 1.34%.

Maximum photovoltaic power tracking for the PV array using the fractional-order incremental conductance method

International Nuclear Information System (INIS)

Lin, Chia-Hung; Huang, Cong-Hui; Du, Yi-Chun; Chen, Jian-Liung

2011-01-01

Highlights: → The FOICM can shorten the tracking time less than traditional methods. → The proposed method can work under lower solar radiation including thin and heavy clouds. → The FOICM algorithm can achieve MPPT for radiation and temperature changes. → It is easy to implement in a single-chip microcontroller or embedded system. -- Abstract: This paper proposes maximum photovoltaic power tracking (MPPT) for the photovoltaic (PV) array using the fractional-order incremental conductance method (FOICM). Since the PV array has low conversion efficiency, and the output power of PV array depends on the operation environments, such as various solar radiation, environment temperature, and weather conditions. Maximum charging power can be increased to a battery using a MPPT algorithm. The energy conversion of the absorbed solar light and cell temperature is directly transferred to the semiconductor, but electricity conduction has anomalous diffusion phenomena in inhomogeneous material. FOICM can provide a dynamic mathematical model to describe non-linear characteristics. The fractional-order incremental change as dynamic variable is used to adjust the PV array voltage toward the maximum power point. For a small-scale PV conversion system, the proposed method is validated by simulation with different operation environments. Compared with traditional methods, experimental results demonstrate the short tracking time and the practicality in MPPT of PV array.

Solar Powered Aircraft, Photovoltaic Array/Battery System Tabletop Demonstration: Design and Operation Manual

Science.gov (United States)

Colozza, Anthony J.; Scheiman, David A.; Bailey, Sheila (Technical Monitor)

2000-01-01

A system was constructed to demonstrate the power system operation of a solar powered aircraft. The system consists of a photovoltaic (PV) array, a charge controller, a battery, an electric motor and propeller. The system collects energy from the PV array and either utilizes this energy to operate an electric motor or stores it in a rechargeable battery for future use. The system has a control panel which displays the output of the array and battery as well as the total current going to the electric motor. The control panel also has a means for adjusting the output to the motor to control its speed. The entire system is regulated around 12 VDC.

Standard Test Method for Wet Insulation Integrity Testing of Photovoltaic Arrays

CERN Document Server

American Society for Testing and Materials. Philadelphia

2010-01-01

1.1 This test method covers a procedure to determine the insulation resistance of a photovoltaic (PV) array (or its component strings), that is, the electrical resistance between the array's internal electrical components and is exposed, electrically conductive, non-current carrying parts and surfaces of the array. 1.2 This test method does not establish pass or fail levels. The determination of acceptable or unacceptable results is beyond the scope of this test method. 1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Road map for photovoltaic electricity

International Nuclear Information System (INIS)

2011-02-01

This road map aims at highlighting industrial, technological and social challenges, at elaborating comprehensive visions, at highlighting technological locks, and at outlining research needs for the photovoltaic sector. It considers the following sector components: preparation of photo-sensitive materials, manufacturing of photovoltaic cells, manufacturing of photovoltaic arrays, design and manufacturing of electric equipment to control photovoltaic arrays and to connect them to the grid. It highlights the demand for photovoltaic installations, analyzes the value chain, proposes a vision of the sector by 2050 and defines target for 2020, discusses needs for demonstration and experimentation

Citation Patterns to Traditional and Electronic Preprints in the Published Literature.

Science.gov (United States)

Youngen, Gregory K.

1998-01-01

Identifies the growing importance of electronic preprints in the published literature of physics and astronomy and address several areas of concern regarding the future role of electronic preprints in scientific communication. Topics include a history of preprints in astronomy and physics; inaccuracies in preprint citations; and archival issues.…

The mini-dome Fresnel lens photovoltaic concentrator array - Current status of component and prototype panel testing

Science.gov (United States)

Piszczor, M. F.; Swartz, C. K.; O'Neill, M. J.; Mcdanal, A. J.; Fraas, L. M.

1990-01-01

NASA Lewis and ENTECH have been developing a high-efficiency, lightweight space photovoltaic concentrator array. The emphasis of the program has shifted to fabrication and testing of the minidome Fresnel lens and other array components. Protototype lenses have been tested for optical efficiency, with results around 90 percent, and tracking error performance. The results of these tests have been very consistent with the predicted analytical performance. Work has also progressed in the fabrication of the array support structure. Recent advances in 30 percent efficient stacked cell technology will have a significant effect on the array performance. It is concluded that near-term array performance goals of 300 W/sq m and 100 W/kg are feasible.

A photovoltaic catenary-tent array for the Martian surface

Science.gov (United States)

Crutchik, M.; Colozza, Anthony J.; Appelbaum, J.

1993-01-01

To provide electrical power during an exploration mission to Mars, a deployable tent-shaped structure with a flexible photovoltaic (PV) blanket is proposed. The array is designed with a self-deploying mechanism utilizing pressurized gas expansion. The structural design for the array uses a combination of cables, beams, and columns to support and deploy the PV blanket. Under the force of gravity a cable carrying a uniform load will take the shape of a catenary curve. A catenary-tent collector is self shadowing which must be taken into account in the solar radiation calculation. The shape and the area of the shadow on the array was calculated and used in the determination of the global radiation on the array. The PV blanket shape and structure dimension were optimized to achieve a configuration which maximizes the specific power (W/kg). The optimization was performed for four types of PV blankets (Si, GaAs/Ge, GaAs CLEFT, and amorphous Si) and four types of structure materials (Carbon composite, Aramid Fiber composite, Aluminum, and Magnesium). The results show that the catenary shape of the PV blanket, which produces the highest specific power, corresponds to zero end angle at the base with respect to the horizontal. The tent angle is determined by the combined effect of the array structure specific mass and the PV blanket output power. The combination of carbon composite structural material and GaAs CLEFT solar cells produce the highest specific power. The study was carried out for two sites on Mars corresponding to the Viking Lander locations. The designs were also compared for summer, winter, and yearly operation.

Siting Solar Photovoltaics at Airports: Preprint

Energy Technology Data Exchange (ETDEWEB)

Kandt, A.; Romero, R.

2014-06-01

Airports present a significant opportunity for hosting solar technologies due to their open land; based on a 2010 Federal Aviation Administration study, the US Department of Agriculture, and the US Fish and Wildlife Service, there's potential for 116,704 MW of solar photovoltaics (PV) on idle lands at US airports. PV has a low profile and likely low to no impact on flight operations. This paper outlines guidance for implementing solar technologies at airports and airfields, focusing largely on the Federal Aviation Administration's policies. The paper also details best practices for siting solar at airports, provides information on the Solar Glare Hazard Analysis Tool, and highlights a case study example where solar has been installed at an airport.

Glass fiber reinforced concrete for terrestrial photovoltaic arrays

Science.gov (United States)

Maxwell, H.

1979-01-01

The use of glass-fiber-reinforced concrete (GRC) as a low-cost structural substrate for terrestrial solar cell arrays is discussed. The properties and fabrication of glass-reinforced concrete structures are considered, and a preliminary design for a laminated solar cell assembly built on a GRC substrate is presented. A total cost for such a photovoltaic module, composed of a Korad acrylic plastic film front cover, an aluminum foil back cover, an ethylene/vinyl acetate pottant/adhesive and a cotton fabric electrical isolator in addition to the GRC substrate, of $9.42/sq m is projected, which is less than the $11.00/sq m cost goal set by the Department of Energy. Preliminary evaluations are concluded to have shown the design capabilities and cost effectiveness of GRC; however, its potential for automated mass production has yet to be evaluated.

PC database for high energy preprint collections

International Nuclear Information System (INIS)

Haymaker, R.

1985-06-01

We describe a microcomputer database used by the high energy group to keep track of preprints in our collection. It is used as a supplement to the SLAC-SPIRES database to retrieve preprints on hand. This was designed as a low overhead system for a small group

Temperature compensated photovoltaic array

Science.gov (United States)

Mosher, Dan Michael

1997-11-18

A temperature compensated photovoltaic module (20) comprised of a series of solar cells (22) having a thermally activated switch (24) connected in parallel with several of the cells (22). The photovoltaic module (20) is adapted to charge conventional batteries having a temperature coefficient (TC) differing from the temperature coefficient (TC) of the module (20). The calibration temperatures of the switches (24) are chosen whereby the colder the ambient temperature for the module (20), the more switches that are on and form a closed circuit to short the associated solar cells (22). By shorting some of the solar cells (22) as the ambient temperature decreases, the battery being charged by the module (20) is not excessively overcharged at lower temperatures. PV module (20) is an integrated solution that is reliable and inexpensive.

Teaching Photovoltaic Array Modelling and Characterization Using a Graphical User Interface and a Flash Solar Simulator

DEFF Research Database (Denmark)

Spataru, Sergiu; Sera, Dezso; Kerekes, Tamas

2012-01-01

This paper presents a set of laboratory tools aimed to support students with various backgrounds (no programming) to understand photovoltaic array modelling and characterization techniques. A graphical user interface (GUI) has been developed in Matlab, for modelling PV arrays and characterizing...... the effect of different types of parameters and operating conditions, on the current-voltage and power-voltage curves. The GUI is supported by experimental investigation and validation on PV module level, with the help of an indoor flash solar simulator....

Electricity from photovoltaic solar cells: Flat-Plate Solar Array Project final Report. Volume II: Silicon material

OpenAIRE

Lutwack, R.

1986-01-01

The Flat-Plate Solar Array (FSA) Project, funded by the U.S. Government and managed by the Jet Propulsion Laboratory, was formed in 1975 to develop the module/array technology needed to attain widespread terrestrial use of photovoltaics by 1985. To accomplish this, the FSA Project established and managed an Industry, University, and Federal Government Team to perform the needed research and development. The goal of the Silicon Material Task, a part of the FSA Project, was to develop and ...

Multiple Solutions for Reconfiguration to Address Partial Shading Losses in Solar Photovoltaic Arrays

Science.gov (United States)

Sharma, Nikesh; Pareek, Smita; Chaturvedi, Nitin; Dahiya, Ratna

2018-03-01

Solar photovoltaic (SPV) systems are steadily rising and considered as the best alternatives to meet the rising demand of energy. In developing countries like India, SPV’s contribution being a clean energy is the most favourable. However, experiences have shown that produced power of these systems is usually affected due to day, night, seasonal variations, insolation, partial shading conditions etc. Among these parameters, partial shading causes a huge reduction in output power of PV systems. This results in lack of confidence for this technology among users. Thus, it is important and a major challenge in PV systems to minimize the effect of partial shading on their energy production. The work in this paper aims to propose solutions for reconfiguration of solar photovoltaic arrays in order to reduce partial shading losses and thus to enhance power generation.

A Real-Time Systems Symposium Preprint.

Science.gov (United States)

1983-09-01

Real - Time Systems Symposium Preprint Interim Tech...estimate of the occurence of the error. Unclassii ledSECUqITY CLASSIF’ICA T" NO MI*IA If’ inDI /’rrd erter for~~ble. ’Corrputnqg A REAL - TIME SYSTEMS SYMPOSIUM...ABSTRACT This technical report contains a preprint of a paper accepted for presentation at the REAL - TIME SYSTEMS SYMPOSIUM, Arlington,

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

International Nuclear Information System (INIS)

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

2011-01-01

Highlights: → The performances of solar cell arrays based on a Trough Concentrating Photovoltaic/Thermal (TCPV/T) system have been studied. → The optimum concentration ratios for the single crystalline silicon cell, the Super cells and the GaAs cells were studied by experiments. → The influences between the solar cell's performance and the series resistances, the working temperature, solar irradiation intensity were explored. - Abstract: 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 the polysilicon cells exhibited poor performance characteristics under concentrating conditions. The optimum concentration ratios for the single crystalline silicon cell, the Super cells and the GaAs cells were also studied by experiments. The optimum concentration ratios for the single crystalline silicon cells and Super cells were 4.23 and 8.46 respectively, and the triple junction GaAs cells could work well at higher concentration ratio. Besides, some theoretical calculations and experiments were performed to explore the influences of the series resistances and the working temperature. When the series resistances R s changed from 0 Ω to 1 Ω, the maximum power P m of the single crystalline silicon, the polycrystalline silicon, the Super cell and the GaAs cell arrays decreased by 67.78%, 74.93%, 77.30% and 58.07% respectively. When the cell temperature increased by 1 K, the short circuit current of the four types of solar cell arrays decreased by 0.11818 A, 0.05364 A, 0.01387 A and 0.00215 A respectively. The research results demonstrated that the output performance of the solar cell arrays with lower

Production. Which price for photovoltaic?

International Nuclear Information System (INIS)

Dupin, L.

2011-01-01

As the French government decided to reduce its financial support to photovoltaic energy, a first article identifies and comments the issues to be addressed to have a competitive French photovoltaic industry: to bet on second generation arrays (thin layer arrays), to have higher yearly objectives in terms of installed power (800 MW or 1 GW instead of 500 MW, in order to create a reference market), to redefine the financing and the electricity purchase scheme, to promote self consumption, to support exportation. The second article presents the first French photovoltaic test and certification centre, located near Chambery, where solar arrays are inspected and where their ageing is simulated through thermal fatigue and impact testing

Relative potentials of concentrating and two-axis tracking flat-plate photovoltaic arrays for central-station applications

Science.gov (United States)

Borden, C. S.; Schwartz, D. L.

1984-01-01

The purpose of this study is to assess the relative economic potentials of concenrating and two-axis tracking flat-plate photovoltaic arrays for central-station applications in the mid-1990's. Specific objectives of this study are to provide information on concentrator photovoltaic collector probabilistic price and efficiency levels to illustrate critical areas of R&D for concentrator cells and collectors, and to compare concentrator and flat-plate PV price and efficiency alternatives for several locations, based on their implied costs of energy. To deal with the uncertainties surrounding research and development activities in general, a probabilistic assessment of commercially achievable concentrator photovoltaic collector efficiencies and prices (at the factory loading dock) is performed. The results of this projection of concentrator photovoltaic technology are then compared with a previous flat-plate module price analysis (performed early in 1983). To focus this analysis on specific collector alternatives and their implied energy costs for different locations, similar two-axis tracking designs are assumed for both concentrator and flat-plate options.

NREL preprints for the photovoltaic specialists conference of IEEE twenty-five

Energy Technology Data Exchange (ETDEWEB)

Gwinner, D. [ed.

1996-05-01

This volume contains 40 papers prepared for presentation at the conference. Topics include: material properties, fabrication of solar cells, thermophotovoltaics, performance efficiency of photovoltaic cells, gettering procedures, market development, and photovoltaic power supplies for remote areas. Materials for solar cells include: Si, CuInSe{sub 2}, CuInGaSe{sub 2}, GaInP, GaAs, CdTe, and CdS. Papers have been processed separately for inclusion on the data base.

EPRI 25kW high concentration photovoltaic integrated array concept and associated economics

International Nuclear Information System (INIS)

Gunn, J.A.; Dostalek, F.J.

1993-01-01

This paper describes a cost effective photovoltaic array design for the high concentration technology being developed by the Electric Power Research Institute for utility scale applications. The concept of an ''integrated array'' is to attach Fresnel lens parquets directly to the front of the tracker structure and PV panels directly to the back of the structure thereby eliminating redundant structural components. The concept also incorporates the maximum use of automated manufacturing techniques for all components thereby minimizing material waste, fabrication and assembly labor. This paper also describes the results of a first approach cost and economic study for the technology which shows the potential for levelized energy cost below $0.10/kWh for a 50 MW ac plant given a mature technology

Self-Cleaning Microcavity Array for Photovoltaic Modules.

Science.gov (United States)

Vüllers, Felix; Fritz, Benjamin; Roslizar, Aiman; Striegel, Andreas; Guttmann, Markus; Richards, Bryce S; Hölscher, Hendrik; Gomard, Guillaume; Klampaftis, Efthymios; Kavalenka, Maryna N

2018-01-24

Development of self-cleaning coatings is of great interest for the photovoltaic (PV) industry, as soiling of the modules can significantly reduce their electrical output and increase operational costs. We fabricated flexible polymeric films with novel disordered microcavity array (MCA) topography from fluorinated ethylene propylene (FEP) by hot embossing. Because of their superhydrophobicity with water contact angles above 150° and roll-off angles below 5°, the films possess self-cleaning properties over a wide range of tilt angles, starting at 10°, and contaminant sizes (30-900 μm). Droplets that impact the FEP MCA surface with velocities of the same order of magnitude as that of rain bounce off the surface without impairing its wetting properties. Additionally, the disordered MCA topography of the films enhances the performance of PV devices by improving light incoupling. Optical coupling of the FEP MCA films to a glass-encapsulated multicrystalline silicon solar cell results in 4.6% enhancement of the electrical output compared to that of an uncoated device.

Proceedings of the flat-plate solar array project research forum on photovoltaic metallization systems

Energy Technology Data Exchange (ETDEWEB)

None

1983-11-15

A Photovoltaic Metallization Research Forum, under the sponsorship of the Jet Propulsion Laboratory's Flat-Plate Solar Array Project and the US Department of Energy, was held March 16-18, 1983 at Pine Mountain, Georgia. The Forum consisted of five sessions, covering (1) the current status of metallization systems, (2) system design, (3) thick-film metallization, (4) advanced techniques and (5) future metallization challenges. Twenty-three papers were presented.

Harnessing the Sun with Thin Film Photovoltaics: Preprint

International Nuclear Information System (INIS)

Birkmire, R. W.; Kazmerski, L. L.

1999-01-01

Photovoltaic (PV) technologies have a substantial role in meeting electric power needs in the next century, especially with an expected competitive position compared to conventional power-generation and other renewable- energy technologies. Thin-film photovoltaic modules based on CdTe, CuInSe2 or Si can potentially be produced by economical, high-volume manufacturing techniques, dramatically reducing component cost. However, the translation of laboratory thin-film technologies to first-time, large-scale manufacturing has been much more difficult than expected. This is due to the complexity of the processes involved for making large-area PV modules at high rates and with high yields, and compounded by the lack of a fundamental scientific and engineering base required to properly engineer and operate manufacturing equipment. In this paper, we discuss the need to develop diagnostics tools and associated predictive models that quantitatively assess processing conditions and pro duct properties. Incorporation of the diagnostic sensors into both laboratory reactors and manufacturing facilities will (1) underpin the development of solar cells with improved efficiency, and (2) accelerate the scale-up process through intelligent process-control schemes. ''Next-generation'' high-performance (e.g., and gt;25% conversion efficiency) thin-film PV modules will also be assessed, along with critical issues associated with their development

Enhanced model of photovoltaic cell/panel/array considering the direct and reverse modes

Science.gov (United States)

Zegaoui, Abdallah; Boutoubat, Mohamed; Sawicki, Jean-Paul; Kessaissia, Fatma Zohra; Djahbar, Abdelkader; Aillerie, Michel

2018-05-01

This paper presents an improved generalized physical model for photovoltaic, PV cells, panels and arrays taking into account the behavior of these devices when considering their biasing existing in direct and reverse modes. Existing PV physical models generally are very efficient for simulating influence of irradiation changes on the short circuit current but they could not visualize the influences of temperature changes. The Enhanced Direct and Reverse Mode model, named EDRM model, enlightens the influence on the short-circuit current of both temperature and irradiation in the reverse mode of the considered PV devices. Due to its easy implementation, the proposed model can be a useful power tool for the development of new photovoltaic systems taking into account and in a more exhaustive manner, environmental conditions. The developed model was tested on a marketed PV panel and it gives a satisfactory results compared with parameters given in the manufacturer datasheet.

Combination solar photovoltaic heat engine energy converter

Science.gov (United States)

Chubb, Donald L.

1987-01-01

A combination solar photovoltaic heat engine converter is proposed. Such a system is suitable for either terrestrial or space power applications. The combination system has a higher efficiency than either the photovoltaic array or the heat engine alone can attain. Advantages in concentrator and radiator area and receiver mass of the photovoltaic heat engine system over a heat-engine-only system are estimated. A mass and area comparison between the proposed space station organic Rankine power system and a combination PV-heat engine system is made. The critical problem for the proposed converter is the necessity for high temperature photovoltaic array operation. Estimates of the required photovoltaic temperature are presented.

Wire Array Photovoltaics

Science.gov (United States)

Turner-Evans, Dan

Over the past five years, the cost of solar panels has dropped drastically and, in concert, the number of installed modules has risen exponentially. However, solar electricity is still more than twice as expensive as electricity from a natural gas plant. Fortunately, wire array solar cells have emerged as a promising technology for further lowering the cost of solar. Si wire array solar cells are formed with a unique, low cost growth method and use 100 times less material than conventional Si cells. The wires can be embedded in a transparent, flexible polymer to create a free-standing array that can be rolled up for easy installation in a variety of form factors. Furthermore, by incorporating multijunctions into the wire morphology, higher efficiencies can be achieved while taking advantage of the unique defect relaxation pathways afforded by the 3D wire geometry. The work in this thesis shepherded Si wires from undoped arrays to flexible, functional large area devices and laid the groundwork for multijunction wire array cells. Fabrication techniques were developed to turn intrinsic Si wires into full p-n junctions and the wires were passivated with a-Si:H and a-SiNx:H. Single wire devices yielded open circuit voltages of 600 mV and efficiencies of 9%. The arrays were then embedded in a polymer and contacted with a transparent, flexible, Ni nanoparticle and Ag nanowire top contact. The contact connected >99% of the wires in parallel and yielded flexible, substrate free solar cells featuring hundreds of thousands of wires. Building on the success of the Si wire arrays, GaP was epitaxially grown on the material to create heterostructures for photoelectrochemistry. These cells were limited by low absorption in the GaP due to its indirect bandgap, and poor current collection due to a diffusion length of only 80 nm. However, GaAsP on SiGe offers a superior combination of materials, and wire architectures based on these semiconductors were investigated for multijunction

Analisis Mode Sistem Pembangkit Listrik Tenaga Hibrid Microhydro - Photovoltaic Array Menggunakan Homer (Studi Kasus : Kampung Bayang Janiah, Kabupaten Pesisir Selatan

Directory of Open Access Journals (Sweden)

Novi Kurniasih

2015-03-01

Full Text Available In this study discusses the optimization of the design and analysis of engineering economics Hybrid Power Plant Off-Grid Microhydro - Photovoltaic Array with the help of software HOMER 2 version 2.81. Utilization of Hybrid Power Plant System can overcome the electrical problems in Bayang Janiah village, Nagari Koto Ranah, Bayang Utara Subdistrict, Pesisir Selatan District that is far from the reach of the grid and can improve the reliability of electricity economically in which initially operated only 12 hours/day sourced from microhydro power plant only, can be upgraded to full operation 24 hours/day. From the analysis that has been conducted, obtained monthly discharge of Bayang Janiah river availability using dependable discharge F. J. Mock 90% of 102 L/s to 14 m of effective head is able to move the hydro turbine to produce power of about 11,3 kW. Meanwhile, for an array of photovoltaic systems produce power equal to 8.4 kW with a number of solar modules by 84 modules and the number of battery 6 V 1.091 Ah required 8 units and a bidirectional converter with a total capacity of 10 kW, totaling 2 units. HOMER simulation results show that the determination of the configuration of the hybrid power plant system design most optimal for application in Bayang Janiah village lowest Total NPC is based on the integration between microhydro - photovoltaic array - battery bank - bidirectional converter. On the optimal system configuration, microhydro contribution of 78.945 kWh/yr, a photovoltaic array of 11.404 kWh/yr, with a Total NPC of $ 146.041, Levelized COE of $ 0,525/kWh, while the electrical energy consumption of 30.668 kWh per year and has excess energy of 59.608 kWh/yr, so it can meet the needs of household electricity to 56 households as well as social facilities in the village.

Optimalisasi Desain Sistem Pembangkit Listrik Tenaga Hybrid Diesel Generator  Photovoltaic Array Menggunakan Homer (Studi Kasus : Desa Sirilogui, Kabupaten Kepulauan Mentawai

Directory of Open Access Journals (Sweden)

Dewi Purnama Sari

2015-03-01

Full Text Available Hybrid Power Plant is one of the solutions to overcome the shortage of electricity in underdeveloped and isolated areas not covered by PLN electricity network, due to underdeveloped regions generally have the geography and topography that does not allow for expansion of PLN electricity network. Integration of the two power plants is a conventional power plant (diesel generator that comes from fuel oil (BBM with power plants sourced from renewable energy (photovoltaic arrays is an advantageous solution to meet the needs of daily electricity load in remote areas such as the Village Sirilogui located in the District of North Siberut Mentawai Islands, because the integration of photovoltaic arrays diesel generator can provide 24 hour lighting solution for 310 households (families in the village Sirilogui which at first only enjoy the lighting for 4 hours, and even then only at night days, from 06.00 to 10.00 pm o'clock sourced from 3 units of diesel generator. With the integration of these two power plants, diesel generator operation can be minimized so it saves fuel consumption and reduce CO2 emissions caused by the operation of the diesel generator. This study focuses the discussion on Design Optimization of Hybrid Power Plant System Diesel Generator-Photovoltaic Array by using HOMER as a tool for simulation. HOMER software is used to help simplify the task of the modeler in evaluating the design of hybrid power plant system that allows to sort based on the total net present cost (TNPC, the lowest for the most optimal system. In this study, the results of the design for the system with the daily electricity load of 479,280 kWh most optimal based on the simulation results using HOMER ie photovoltaic capacity of 65 kW, 3 units of diesel generators with a capacity of each 15 kW, 156 units of battery and bidirectional converter with a capacity of 78 kW TNPC amounted to $ 1.362.474 and the cost of energy (COE of $ 1,485/kWh. Hybrid Power Plant System

Design of a Solar Motor Drive System Fed by a Direct-Connected Photovoltaic Array

Directory of Open Access Journals (Sweden)

AYDOGMUS, O.

2012-08-01

Full Text Available A solar motor pump drive system is modeled and simulated. The proposed drive system does not require any kind of energy storage system and dc-dc converter. The system is connected directly to a photovoltaic (PV array. Thus, a low cost solar system can be achieved. A vector controlled Permanent Magnet Synchronous Motor (PMSM is used as a solar motor to increase the efficiency of system. The motor is designed for a low rated voltage level about 24V. The hill climbing MPPT method is used for balanced the motor power and PV power to obtain a high efficiency. The results are performed by using MATLAB/SimPowerSystem blocks. In addition, the PV array is modeled to allow for the possibility of running as on-line adjustable in simulation environment without using lookup table. The performances of motor, MPPT and drive system are analyzed in different conditions as temperature and irradiation of PV array.

Safety-related requirements for photovoltaic modules and arrays

Science.gov (United States)

Levins, A.; Smoot, A.; Wagner, R.

1984-01-01

Safety requirements for photovoltaic module and panel designs and configurations for residential, intermediate, and large scale applications are investigated. Concepts for safety systems, where each system is a collection of subsystems which together address the total anticipated hazard situation, are described. Descriptions of hardware, and system usefulness and viability are included. A comparison of these systems, as against the provisions of the 1984 National Electrical Code covering photovoltaic systems is made. A discussion of the Underwriters Laboratory UL investigation of the photovoltaic module evaluated to the provisions of the proposed UL standard for plat plate photovoltaic modules and panels is included. Grounding systems, their basis and nature, and the advantages and disadvantages of each are described. The meaning of frame grounding, circuit groundings, and the type of circuit ground are covered.

Experimental study on direct-contact liquid film cooling simulated dense-array solar cells in high concentrating photovoltaic system

International Nuclear Information System (INIS)

Wang, Yiping; Shi, Xusheng; Huang, Qunwu; Cui, Yong; Kang, Xue

2017-01-01

Highlights: • Direct-contact liquid film cooling dense-array solar cells was first proposed. • Average temperature was controlled well below 80 °C. • The maximum temperature difference was less than 10 °C. • The heat transfer coefficient reached up to 11.91 kW/(m"2·K) under 589X. - Abstract: This paper presented a new method of cooling dense-array solar cells in high concentrating photovoltaic system by direct-contact liquid film, and water was used as working fluid. An electric heating plate was designed to simulate the dense-array solar cells in high concentrating photovoltaic system. The input power of electric heating plate simulated the concentration ratios. By heat transfer experiments, the effect of water temperatures and flow rates on heat transfer performance was investigated. The results indicated that: the average temperature of simulated solar cells was controlled well below 80 °C under water temperature of 30 °C and flow rate of 300 L/h when concentration ratio ranged between 300X and 600X. The maximum temperature difference among temperature measurement points was less than 10 °C, which showed the temperature distribution was well uniform. The heat transfer coefficient reached up to 11.91 kW/(m"2·K) under concentration ratio of 589X. To improve heat transfer performance and obtain low average temperature of dense-array solar cells, lower water temperature and suitable water flow rate are preferred.

Theory for optimal design of waveguiding light concentrators in photovoltaic microcell arrays.

Science.gov (United States)

Semichaevsky, Andrey V; Johnson, Harley T; Yoon, Jongseung; Nuzzo, Ralph G; Li, Lanfang; Rogers, John

2011-06-10

Efficiency of ultrathin flexible solar photovoltaic silicon microcell arrays can be significantly improved using nonimaging solar concentrators. A fluorophore is introduced to match the solar spectrum and the low-reflectivity wavelength range of Si, reduce the escape losses, and allow the nontracking operation. In this paper we optimize our solar concentrators using a luminescent/nonluminescent photon transport model. Key modeling results are compared quantitatively to experiments and are in good agreement with the latter. Our solar concentrator performance is not limited by the dye self-absorption. Bending deformations of the flexible solar collectors do not result in their indirect gain degradation compared to flat solar concentrators with the same projected area.

Solar radiation on Mars: Stationary photovoltaic array

Science.gov (United States)

Appelbaum, J.; Sherman, I.; Landis, G. A.

1993-01-01

Solar energy is likely to be an important power source for surface-based operation on Mars. Photovoltaic cells offer many advantages. In this article we have presented analytical expressions and solar radiation data for stationary flat surfaces (horizontal and inclined) as a function of latitude, season and atmospheric dust load (optical depth). The diffuse component of the solar radiation on Mars can be significant, thus greatly affecting the optimal inclination angle of the photovoltaic surface.

Systematic procedures for sizing photovoltaic pumping system, using water tank storage

International Nuclear Information System (INIS)

Hamidat, A.; Benyoucef, B.

2009-01-01

In this work, the performances of the photovoltaic pumping destined to supply drinking water in remote and scattered small villages have been studied. The methodology adopted proposes various procedures based on the water consumption profiles, total head, tank capacity and photovoltaic array peak power. A method of the load losses probability (LLP) has been used to optimize sizing of the photovoltaic pumping systems with a similarity between the storage energy in batteries and water in tanks. The results were carried out using measured meteorological data for four localities in Algeria: Algiers and Oran in the north, Bechar and Tamanrasset in the south. The results show that the performance of the photovoltaic pumping system depends deeply on the pumping total head and the peak power of the photovoltaic array. Also, for the southern localities, the LLP method shows that the size of the photovoltaic array varies versus LLP on a small scale. On the other hand, for the northern localities, the sizing of the photovoltaic array is situated on a large scale power. Because of the current high crud-oil price, the photovoltaic pumping still to be the best adopted energy resource to supply drinking water in remote and scattered villages

A general modeling method for I-V characteristics of geometrically and electrically configured photovoltaic arrays

International Nuclear Information System (INIS)

Liu Guangyu; Nguang, Sing Kiong; Partridge, Ashton

2011-01-01

Highlights: → A novel and general method is proposed for modeling PV arrays or modules. → A robust algorithm is used for the first time to improve the convergence to solution. → Auxiliary functions in other general methods are not compulsory in our method. → It is novel that geometric configuration is also incorporated. → A case study is performed to show the approach's advantages and unique features. - Abstract: A general method for modeling typical photovoltaic (PV) arrays and modules is proposed to find the exact current and voltage relationship of PV arrays or modules of geometrically and electrically different configurations. Nonlinear characteristic equations of electrical devices in solar array or module systems are numerically constructed without adding any virtual electrical components. Then, a robust damped Newton method is used to find exact I-V relationship of these general nonlinear equations, where the convergence is guaranteed. The model can deal with different mismatch effects such as different configurations of bypass diodes, and partial shading. Geometry coordinates of PV components are also considered to facilitate the modeling of the actual physical configuration. Simulation of a PV array with 48 modules, partially shaded by a concrete structure, is performed to verify the effectiveness and advantages of the proposed method.

Design, testing, and economics of a 430 W sub p photovoltaic concentrator array for non grid-connected applications

Science.gov (United States)

Maish, A. B.; Rios, M., Jr.; Togami, H.

A stand-alone 430 W/sub p/ photovoltaic (PV) concentrating system for low power, non grid-connected applications has been designed, fabricated, and tested at Sandia National Laboratories. The array consists of four passively cooled Fresnel lens concentrating modules on a newly developed polar axis tracking structure. Two axis tracking is provided using a self powered clock drive unit mounted on a single post foundation. Test results of tracking accuracy, array output power, parasitic power, performance in winds and array reliability are discussed. using a range of estimated production costs for small production volumes, the life-cycle energy costs have been calculated and compared to the equivalent energy costs of a 3 kW diesel electric generator set and of an equivalent flat panel PV system.

Broadband High Efficiency Fractal-Like and Diverse Geometry Silicon Nanowire Arrays for Photovoltaic Applications

Science.gov (United States)

AL-Zoubi, Omar H.

Solar energy has many advantages over conventional sources of energy. It is abundant, clean and sustainable. One way to convert solar energy directly into electrical energy is by using the photovoltaic solar cells (PVSC). Despite PVSC are becoming economically competitive, they still have high cost and low light to electricity conversion efficiency. Therefore, increasing the efficiency and reducing the cost are key elements for producing economically more competitive PVSC that would have significant impact on energy market and saving environment. A significant percentage of the PVSC cost is due to the materials cost. For that, thin films PVSC have been proposed which offer the benefits of the low amount of material and fabrication costs. Regrettably, thin film PVSC show poor light to electricity conversion efficiency because of many factors especially the high optical losses. To enhance conversion efficiency, numerous techniques have been proposed to reduce the optical losses and to enhance the absorption of light in thin film PVSC. One promising technique is the nanowire (NW) arrays in general and the silicon nanowire (SiNW) arrays in particular. The purpose of this research is to introduce vertically aligned SiNW arrays with enhanced and broadband absorption covering the entire solar spectrum while simultaneously reducing the amount of material used. To this end, we apply new concept for designing SiNW arrays based on employing diversity of physical dimensions, especially radial diversity within certain lattice configurations. In order to study the interaction of light with SiNW arrays and compute their optical properties, electromagnetic numerical modeling is used. A commercial numerical electromagnetic solver software package, high frequency structure simulation (HFSS), is utilized to model the SiNW arrays and to study their optical properties. We studied different geometries factors that affect the optical properties of SiNW arrays. Based on this study, we

Catalyst-free, III-V nanowire photovoltaics

Science.gov (United States)

Davies, D. G.; Lambert, N.; Fry, P. W.; Foster, A.; Krysa, A. B.; Wilson, L. R.

2014-05-01

We report on room temperature, photovoltaic operation of catalyst-free GaAs p-i-n junction nanowire arrays. Growth studies were first performed to determine the optimum conditions for controlling the vertical and lateral growth of the nanowires. Following this, devices consisting of axial p-i-n junctions were fabricated by planarising the nanowire arrays with a hard baked polymer. We discuss the photovoltaic properties of this proof-of-concept device, and significant improvements to be made during the growth.

Grounds of two positions photovoltaic panels

OpenAIRE

Castán Fortuño, Fernando

2008-01-01

The objective of this Master Thesis is to find the optimum positioning for a two positions photovoltaic panel. Hence, it will be implemented a model in order to optimize the energy of the sun that the photovoltaic panel is receiving by its positioning. Likewise this project will include the comparison with other photovoltaic panel systems as the single position photovoltaics panels. Ultimately, it is also going to be designed a system array for the optimized model of two positions photovoltai...

Photovoltaic cell module and method of forming

Science.gov (United States)

Howell, Malinda; Juen, Donnie; Ketola, Barry; Tomalia, Mary Kay

2017-12-12

A photovoltaic cell module, a photovoltaic array including at least two modules, and a method of forming the module are provided. The module includes a first outermost layer and a photovoltaic cell disposed on the first outermost layer. The module also includes a second outermost layer disposed on the photovoltaic cell and sandwiching the photovoltaic cell between the second outermost layer and the first outermost layer. The method of forming the module includes the steps of disposing the photovoltaic cell on the first outermost layer, disposing a silicone composition on the photovoltaic cell, and compressing the first outermost layer, the photovoltaic cell, and the second layer to form the photovoltaic cell module.

Measurement techniques and instruments suitable for life-prediction testing of photovoltaic arrays. Interim report

Energy Technology Data Exchange (ETDEWEB)

Noel, G.T.; Sliemers, F.A.; Deringer, G.C.; Wood, V.E.; Wilkes, K.E.; Gaines, G.B.; Carmichael, D.C.

1978-01-15

The validation of a service life of 20 years for low-cost photovoltaic arrays must be accomplished through accelerated life-prediction tests. A methodology for such tests has been developed in a preceding study. The results discussed consist of the initial identification and assessment of all known measurement techniques and instruments that might be used in these life-prediction tests. Array failure modes, relevant materials property changes, and primary degradation mechanisms are discussed as a prerequisite to identifying suitable measurement techniques and instruments. Candidate techniques and instruments are identified on the basis of extensive reviews of published and unpublished information. These methods are organized in six measurement categories--chemical, electrical, optical, thermal, mechanical, and ''other physicals''. Using specified evaluation criteria, the most promising techniques and instruments for use in life-prediction tests of arrays are then selected. These recommended techniques and their characteristics are described. Recommendations are made regarding establishment of the adequacy, particularly with respect to precision, of the more fully developed techniques for this application, and regarding the experimental evaluation of promising developmental techniques. Measurement needs not satisfied by presently available techniques/instruments are also identified.

Space Environment Testing of Photovoltaic Array Systems at NASA's Marshall Space Flight Center

Science.gov (United States)

Phillips, Brandon S.; Schneider, Todd A.; Vaughn, Jason A.; Wright, Kenneth H., Jr.

2015-01-01

To successfully operate a photovoltaic (PV) array system in space requires planning and testing to account for the effects of the space environment. It is critical to understand space environment interactions not only on the PV components, but also the array substrate materials, wiring harnesses, connectors, and protection circuitry (e.g. blocking diodes). Key elements of the space environment which must be accounted for in a PV system design include: Solar Photon Radiation, Charged Particle Radiation, Plasma, and Thermal Cycling. While solar photon radiation is central to generating power in PV systems, the complete spectrum includes short wavelength ultraviolet components, which photo-ionize materials, as well as long wavelength infrared which heat materials. High energy electron radiation has been demonstrated to significantly reduce the output power of III-V type PV cells; and proton radiation damages material surfaces - often impacting coverglasses and antireflective coatings. Plasma environments influence electrostatic charging of PV array materials, and must be understood to ensure that long duration arcs do not form and potentially destroy PV cells. Thermal cycling impacts all components on a PV array by inducing stresses due to thermal expansion and contraction. Given such demanding environments, and the complexity of structures and materials that form a PV array system, mission success can only be ensured through realistic testing in the laboratory. NASA's Marshall Space Flight Center has developed a broad space environment test capability to allow PV array designers and manufacturers to verify their system's integrity and avoid costly on-orbit failures. The Marshall Space Flight Center test capabilities are available to government, commercial, and university customers. Test solutions are tailored to meet the customer's needs, and can include performance assessments, such as flash testing in the case of PV cells.

The prehistory of biology preprints: A forgotten experiment from the 1960s.

Directory of Open Access Journals (Sweden)

Matthew Cobb

2017-11-01

Full Text Available In 1961, the National Institutes of Health (NIH began to circulate biological preprints in a forgotten experiment called the Information Exchange Groups (IEGs. This system eventually attracted over 3,600 participants and saw the production of over 2,500 different documents, but by 1967, it was effectively shut down following the refusal of journals to accept articles that had been circulated as preprints. This article charts the rise and fall of the IEGs and explores the parallels with the 1990s and the biomedical preprint movement of today.

The prehistory of biology preprints: A forgotten experiment from the 1960s.

Science.gov (United States)

Cobb, Matthew

2017-11-01

In 1961, the National Institutes of Health (NIH) began to circulate biological preprints in a forgotten experiment called the Information Exchange Groups (IEGs). This system eventually attracted over 3,600 participants and saw the production of over 2,500 different documents, but by 1967, it was effectively shut down following the refusal of journals to accept articles that had been circulated as preprints. This article charts the rise and fall of the IEGs and explores the parallels with the 1990s and the biomedical preprint movement of today.

Solar photovoltaic/thermal residential experiment. Phase I. Final report

Energy Technology Data Exchange (ETDEWEB)

Darkazalli, G.

1980-07-01

Month-by-month energy transfer data between an occupied residence and its energy supply systems are presented. The data were obtained during the first phase of photovoltaic/thermal residential research conducted at the University of Texas at Arlington/Solar Energy Research Facility. This research was part of the US Department of Energy Photovoltaic/Thermal Project managed by the M.I.T. Lincoln Laboratory. Energy transfer data are divided into different categories depending on how the energy is consumed. Energy transfers between some system components are also categorized. These components include a flat-plate thermal collector array, a flat-plate photovoltaic array, a dc-to-ac inverter, thermal storage tanks, and a series heat pump. System operations included directing surplus electrical energy (generated by the photovoltaic array) into the local utility grid. The heat pump used off-peak utility power to chill water during the cooling season.

Performance characteristics of a combination solar photovoltaic heat engine energy converter

Science.gov (United States)

Chubb, Donald L.

1987-01-01

A combination solar photovoltaic heat engine converter is proposed. Such a system is suitable for either terrestrial or space power applications. The combination system has a higher efficiency than either the photovoltaic array or the heat engine alone can attain. Advantages in concentrator and radiator area and receiver mass of the photovoltaic heat engine system over a heat-engine-only system are estimated. A mass and area comparison between the proposed space station organic Rankine power system and a combination PV-heat engine system is made. The critical problem for the proposed converter is the necessity for high temperature photovoltaic array operation. Estimates of the required photovoltaic temperature are presented.

Distributed solar photovoltaic array location and extent dataset for remote sensing object identification

Science.gov (United States)

Bradbury, Kyle; Saboo, Raghav; L. Johnson, Timothy; Malof, Jordan M.; Devarajan, Arjun; Zhang, Wuming; M. Collins, Leslie; G. Newell, Richard

2016-12-01

Earth-observing remote sensing data, including aerial photography and satellite imagery, offer a snapshot of the world from which we can learn about the state of natural resources and the built environment. The components of energy systems that are visible from above can be automatically assessed with these remote sensing data when processed with machine learning methods. Here, we focus on the information gap in distributed solar photovoltaic (PV) arrays, of which there is limited public data on solar PV deployments at small geographic scales. We created a dataset of solar PV arrays to initiate and develop the process of automatically identifying solar PV locations using remote sensing imagery. This dataset contains the geospatial coordinates and border vertices for over 19,000 solar panels across 601 high-resolution images from four cities in California. Dataset applications include training object detection and other machine learning algorithms that use remote sensing imagery, developing specific algorithms for predictive detection of distributed PV systems, estimating installed PV capacity, and analysis of the socioeconomic correlates of PV deployment.

Global Maximum Power Point Tracking (MPPT of a Photovoltaic Module Array Constructed through Improved Teaching-Learning-Based Optimization

Directory of Open Access Journals (Sweden)

Kuei-Hsiang Chao

2016-11-01

Full Text Available The present study proposes a maximum power point tracking (MPPT method in which improved teaching-learning-based optimization (I-TLBO is applied to perform global MPPT of photovoltaic (PV module arrays under dissimilar shading situations to ensure the maximum power output of the module arrays. The proposed I-TLBO enables the automatic adjustment of teaching factors according to the self-learning ability of students. Incorporating smart-tracking and self-study strategies can effectively improve the tracking response speed and steady-state tracking performance. To evaluate the feasibility of the proposed I-TLBO, a HIP-2717 PV module array from Sanyo Electric was employed to compose various arrays with different serial and parallel configurations. The arrays were operated under different shading conditions to test the MPPT with double, triple, or quadruple peaks of power-voltage characteristic curves. Boost converters were employed with TMS320F2808 digital signal processors to test the proposed MPPT method. Empirical results confirm that the proposed method exhibits more favorable dynamic and static-state response tracking performance compared with that of conventional TLBO.

Arrays of ZnO/CuInxGa1−xSe2 nanocables with tunable shell composition for efficient photovoltaics

International Nuclear Information System (INIS)

Akram, Muhammad Aftab; Javed, Sofia; Xu, Jun; Mujahid, Mohammad; Lee, Chun-Sing

2015-01-01

Arrays of one-dimensional (1D) nanostructure are receiving much attention for their optoelectronic and photovoltaic applications due to their advantages in light absorption, charge separation, and transportation. In this work, arrays of ZnO/CuIn x Ga 1−x Se 2 core/shell nanocables with tunable shell compositions over the full range of 0 ≤ x ≤ 1 have been controllably synthesized. Chemical conversions of ZnO nanorods to a series of ZnO-based nanocables, including ZnO/ZnSe, ZnO/CuSe, ZnO/CuSe/In x Ga 1−x , ZnO/CuSe/(In x Ga 1−x ) 2 Se 3 , and ZnO/CuIn x Ga 1−x Se 2 , are well designed and successfully achieved. Composition-dependent influences of the CuIn x Ga 1−x Se 2 shells on photovoltaic performance are investigated. It is found that the increase in indium content (x) leads to an increase in short-circuit current density (J SC ) but a decrease in open-circuit voltage (V OC ) for the ZnO/CuIn x Ga 1−x Se 2 nanocable solar cells. An array of ZnO/CuIn 0.67 Ga 0.33 Se 2 nanocables with a length of ∼1 μm and a shell thickness of ∼10 nm exhibits a bandgap of 1.20 eV, and yields a maximum power conversion efficiency of 1.74% under AM 1.5 G illumination at an intensity of 100 mW/cm 2 . It dramatically surpasses that (0.22%) of the ZnO/CuIn 0.67 Ga 0.33 Se 2 planar thin-film device. Our work reveals that 1D nanoarray allows efficient photovoltaics without using toxic CdS buffer layer

Road map for photovoltaic electricity; Feuille de route sur l'electricite photovoltaique

Energy Technology Data Exchange (ETDEWEB)

NONE

2011-02-15

This road map aims at highlighting industrial, technological and social challenges, at elaborating comprehensive visions, at highlighting technological locks, and at outlining research needs for the photovoltaic sector. It considers the following sector components: preparation of photo-sensitive materials, manufacturing of photovoltaic cells, manufacturing of photovoltaic arrays, design and manufacturing of electric equipment to control photovoltaic arrays and to connect them to the grid. It highlights the demand for photovoltaic installations, analyzes the value chain, proposes a vision of the sector by 2050 and defines target for 2020, discusses needs for demonstration and experimentation

Design optimization of photovoltaic powered water pumping systems

International Nuclear Information System (INIS)

Ghoneim, A.A.

2006-01-01

The use of photovoltaics as the power source for pumping water is one of the most promising areas in photovoltaic applications. With the increased use of water pumping systems, more attention has been paid to their design and optimum utilization in order to achieve the most reliable and economical operation. This paper presents the results of performance optimization of a photovoltaic powered water pumping system in the Kuwait climate. The direct coupled photovoltaic water pumping system studied consists of the PV array, DC motor, centrifugal pump, a storage tank that serves a similar purpose to battery storage and a maximum power point tracker to improve the efficiency of the system. The pumped water is desired to satisfy the domestic needs of 300 persons in a remote area in Kuwait. Assuming a figure of 40 l/person/day for water consumption, a volume of 12 m 3 should be pumped daily from a deep well throughout the year. A computer simulation program is developed to determine the performance of the proposed system in the Kuwait climate. The simulation program consists of a component model for the PV array with maximum power point tracker and component models for both the DC motor and the centrifugal pump. The five parameter model is adapted to simulate the performance of amorphous silicon solar cell modules. The size of the PV array, PV array orientation and the pump-motor-hydraulic system characteristics are varied to achieve the optimum performance for the proposed system. The life cycle cost method is implemented to evaluate the economic feasibility of the optimized photovoltaic powered water pumping system. At the current prices of PV modules, the cost of the proposed photovoltaic powered water pumping system is found to be less expensive than the cost of the conventional fuel system. In addition, the expected reduction in the prices of photovoltaic modules in the near future will make photovoltaic powered water pumping systems more feasible

Photovoltaic array: Power conditioner interface characteristics

Science.gov (United States)

Gonzalez, C. C.; Hill, G. M.; Ross, R. G., Jr.

1982-01-01

The electrical output (power, current, and voltage) of flat plate solar arrays changes constantly, due primarily to changes in cell temperature and irradiance level. As a result, array loads such as dc-to-ac power conditioners must be capable of accommodating widely varying input levels while maintaining operation at or near the maximum power point of the array. The array operating characteristics and extreme output limits necessary for the systematic design of array load interfaces under a wide variety of climatic conditions are studied. A number of interface parameters are examined, including optimum operating voltage, voltage energy, maximum power and current limits, and maximum open circuit voltage. The effect of array degradation and I-V curve fill factor or the array power conditioner interface is also discussed. Results are presented as normalized ratios of power conditioner parameters to array parameters, making the results universally applicable to a wide variety of system sizes, sites, and operating modes.

Si Wire-Array Solar Cells

Science.gov (United States)

Boettcher, Shannon

2010-03-01

Micron-scale Si wire arrays are three-dimensional photovoltaic absorbers that enable orthogonalization of light absorption and carrier collection and hence allow for the utilization of relatively impure Si in efficient solar cell designs. The wire arrays are grown by a vapor-liquid-solid-catalyzed process on a crystalline (111) Si wafer lithographically patterned with an array of metal catalyst particles. Following growth, such arrays can be embedded in polymethyldisiloxane (PDMS) and then peeled from the template growth substrate. The result is an unusual photovoltaic material: a flexible, bendable, wafer-thickness crystalline Si absorber. In this paper I will describe: 1. the growth of high-quality Si wires with controllable doping and the evaluation of their photovoltaic energy-conversion performance using a test electrolyte that forms a rectifying conformal semiconductor-liquid contact 2. the observation of enhanced absorption in wire arrays exceeding the conventional light trapping limits for planar Si cells of equivalent material thickness and 3. single-wire and large-area solid-state Si wire-array solar cell results obtained to date with directions for future cell designs based on optical and device physics. In collaboration with Michael Kelzenberg, Morgan Putnam, Joshua Spurgeon, Daniel Turner-Evans, Emily Warren, Nathan Lewis, and Harry Atwater, California Institute of Technology.

Optimized organic photovoltaics with surface plasmons

Science.gov (United States)

Omrane, B.; Landrock, C.; Aristizabal, J.; Patel, J. N.; Chuo, Y.; Kaminska, B.

2010-06-01

In this work, a new approach for optimizing organic photovoltaics using nanostructure arrays exhibiting surface plasmons is presented. Periodic nanohole arrays were fabricated on gold- and silver-coated flexible substrates, and were thereafter used as light transmitting anodes for solar cells. Transmission measurements on the plasmonic thin film made of gold and silver revealed enhanced transmission at specific wavelengths matching those of the photoactive polymer layer. Compared to the indium tin oxide-based photovoltaic cells, the plasmonic solar cells showed overall improvements in efficiency up to 4.8-fold for gold and 5.1-fold for the silver, respectively.

Transformational Element Level Arrays (TELA) Testbed (Preprint)

National Research Council Canada - National Science Library

Dalrymple, Thomas; Buck, Jonathan; Buxa, Peter; McCann, John; Neidhard, Robert; Scalzi, Gary; Shreffler, Caleb; Spendley, Dan; Watson, Paul

2007-01-01

.... Previous work at AFRL has resulted in many technologies that support these needs. Many components exist today that were only theoretical a few years ago, such as phased array antennas that support 10...

Adhesion of Antireflective Coatings in Multijunction Photovoltaics: Preprint

Energy Technology Data Exchange (ETDEWEB)

Brock, Ryan; Dauskardt, Reinhold H.; Miller, David C.

2016-06-16

The development of a new composite dual cantilever beam (cDCB) thin-film adhesion testing method is reported, which allows the measurement of adhesion on the fragile thin substrates used in multijunction photovoltaics. We address the adhesion of several antireflective coating systems on multijunction cells. By varying interface chemistry and morphology, we demonstrate the ensuing effects on adhesion and help to develop an understanding of how high adhesion can be achieved, as adhesion values ranging from 0.5 J/m2 to 10 J/m2 were measured. Damp Heat (85 degrees C/85% RH) was used to invoke degradation of interfacial adhesion. We show that even with germanium substrates that fracture easily, quantitative measurements of adhesion can still be made at high test yield. The cDCB test is discussed as an important new methodology, which can be broadly applied to any system that makes use of thin, brittle, or otherwise fragile substrates.

Photovoltaic Cells and Systems: Current State and Future Trends

OpenAIRE

Hadj Bourdoucen; Joseph A. Jervase; Abdullah Al-Badi; Adel Gastli; Arif Malik

2000-01-01

Photovoltaics is the process of converting solar energy into electrical energy. Any photovoltaic system invariably consists of solar cell arrays and electric power conditioners. Photovoltaic systems are reliable, quiet, safe and both environmentally benign and self-sustaining. In addition, they are cost-effective for applications in remote areas. This paper presents a review of solar system components and integration, manufacturing, applications, and basic research related to photovoltaics. P...

Production. Which price for photovoltaic?; Production - le photovoltaique, a quel prix

Energy Technology Data Exchange (ETDEWEB)

Dupin, L.

2011-02-15

As the French government decided to reduce its financial support to photovoltaic energy, a first article identifies and comments the issues to be addressed to have a competitive French photovoltaic industry: to bet on second generation arrays (thin layer arrays), to have higher yearly objectives in terms of installed power (800 MW or 1 GW instead of 500 MW, in order to create a reference market), to redefine the financing and the electricity purchase scheme, to promote self consumption, to support exportation. The second article presents the first French photovoltaic test and certification centre, located near Chambery, where solar arrays are inspected and where their ageing is simulated through thermal fatigue and impact testing

An Advanced Photovoltaic Array Regulator Module

Science.gov (United States)

Button, Robert M.

1996-01-01

Current trends in satellite design are focused on developing small, reliable, and inexpensive spacecraft. To that end, a modular power management and distribution system is proposed which will help transition the aerospace industry towards an assembly line approach to building spacecraft. The modular system is based on an innovative DC voltage boost converter called the Series Connected Boost Unit (SCBU). The SCBU uses any isolating DC-DC converter and adds a unique series connection. This simple modification provides the SCBU topology with many advantages over existing boost converters. Efficiencies of 94-98%, power densities above 1,000 W/kg, and inherent fault tolerance are just a few of the characteristics presented. Limitations of the SCBU technology are presented, and it is shown that the SCBU makes an ideal photovoltaic an-ay regulator. A set of photovoltaic power system requirements are presented that can be applied to almost any low Earth orbit satellite. Finally, a modular design based on the series connected boost unit is outlined and functional descriptions of the components are given.

Simulation of the optimal size of photovoltaic system using ...

African Journals Online (AJOL)

. ... is composed of photovoltaic array, power tracker, battery storage, inverter and load. The data used were the sunshine duration and solar radiation intensity for ... covered by the photovoltaic system without battery storage, monthly-average ...

One-shot service searches: Preprint repositories at a mouseclick

Energy Technology Data Exchange (ETDEWEB)

Canessa, E [International Centre for Theoretical Physics, Trieste (Italy); Pastore, G [Trieste Univ., Trieste (Italy). Dipt. di Fisica

1996-09-01

In this article we introduce the ICTP-International Centre for Theoretical Physics`s prototype for a ``One-Shot World-Wide Preprints Search`` on the Web. This is a new centralized interface for a global search throughout the most popular scientific preprint repositories. Herein, we briefly discuss our experience with the implementation of this service and propose it as a possible alternative solution to the problem of getting access to the information without being either overloaded with lots of new documents or not being informed at all. (author). 13 refs, 3 figs.

One-shot service searches: Preprint repositories at a mouseclick

International Nuclear Information System (INIS)

Canessa, E.; Pastore, G.

1996-09-01

In this article we introduce the ICTP-International Centre for Theoretical Physics's prototype for a ''One-Shot World-Wide Preprints Search'' on the Web. This is a new centralized interface for a global search throughout the most popular scientific preprint repositories. Herein, we briefly discuss our experience with the implementation of this service and propose it as a possible alternative solution to the problem of getting access to the information without being either overloaded with lots of new documents or not being informed at all. (author). 13 refs, 3 figs

Photonic Design for Photovoltaics

Energy Technology Data Exchange (ETDEWEB)

Kosten, E.; Callahan, D.; Horowitz, K.; Pala, R.; Atwater, H.

2014-08-28

We describe photonic design approaches for silicon photovoltaics including i) trapezoidal broadband light trapping structures ii) broadband light trapping with photonic crystal superlattices iii) III-V/Si nanowire arrays designed for broadband light trapping.

Research on the Electrical Characteristics of Photovoltaic Arrays and Corresponding MPPT Simulation

Directory of Open Access Journals (Sweden)

Shengming Li

2013-05-01

Full Text Available Photovoltaic cells, as the primary part of a solar photovoltaic system, are a nonlinear DC power supply related to multiple parameters. The demand of increasing the generating efficiency of photovoltaic cells requires having a good understanding of their electrical characteristics. In this study, the mathematical and physical model of the photovoltaic cells was built by the means of Matlab and Simulink based on the internal principles and equivalent circuits of the photovoltaic cells. After the simulation of such practical and versatile model, it’s found that the nonlinear P-V and I-V characteristics of the photovoltaic cells, with the change of sunlight intensity and temperature, could be accurately reflected by this high simulation precision model. Furthermore, the Maximum Power Point Tracking method was proposed using the logical formula dP/dI=0 of the maximum power point of photovoltaic cells. This method can simply and fast implement the tracking for the maximum power point.

Analysis and research on Maximum Power Point Tracking of Photovoltaic Array with Fuzzy Logic Control and Three-point Weight Comparison Method

Institute of Scientific and Technical Information of China (English)

LIN; Kuang-Jang; LIN; Chii-Ruey

2010-01-01

The Photovoltaic Array has a best optimal operating point where the array operating can obtain the maximum power.However, the optimal operating point can be compromised by the strength of solar radiation,angle,and by the change of environment and load.Due to the constant changes in these conditions,it has become very difficult to locate the optimal operating point by following a mathematical model.Therefore,this study will focus mostly on the application of Fuzzy Logic Control theory and Three-point Weight Comparison Method in effort to locate the optimal operating point of solar panel and achieve maximum efficiency in power generation. The Three-point Weight Comparison Method is the comparison between the characteristic curves of the voltage of photovoltaic array and output power;it is a rather simple way to track the maximum power.The Fuzzy Logic Control,on the other hand,can be used to solve problems that cannot be effectively dealt with by calculation rules,such as concepts,contemplation, deductive reasoning,and identification.Therefore,this paper uses these two kinds of methods to make simulation successively. The simulation results show that,the Three-point Comparison Method is more effective under the environment with more frequent change of solar radiation;however,the Fuzzy Logic Control has better tacking efficiency under the environment with violent change of solar radiation.

Microsystem enabled photovoltaic modules and systems

Science.gov (United States)

Nielson, Gregory N; Sweatt, William C; Okandan, Murat

2015-05-12

A microsystem enabled photovoltaic (MEPV) module including: an absorber layer; a fixed optic layer coupled to the absorber layer; a translatable optic layer; a translation stage coupled between the fixed and translatable optic layers; and a motion processor electrically coupled to the translation stage to controls motion of the translatable optic layer relative to the fixed optic layer. The absorber layer includes an array of photovoltaic (PV) elements. The fixed optic layer includes an array of quasi-collimating (QC) micro-optical elements designed and arranged to couple incident radiation from an intermediate image formed by the translatable optic layer into one of the PV elements such that it is quasi-collimated. The translatable optic layer includes an array of focusing micro-optical elements corresponding to the QC micro-optical element array. Each focusing micro-optical element is designed to produce a quasi-telecentric intermediate image from substantially collimated radiation incident within a predetermined field of view.

Technology developments toward 30-year-life of photovoltaic modules

Science.gov (United States)

Ross, R. G., Jr.

1984-01-01

As part of the United States National Photovoltaics Program, the Jet Propulsion Laboratory's Flat-Plate Solar Array Project (FSA) has maintained a comprehensive reliability and engineering sciences activity addressed toward understanding the reliability attributes of terrestrial flat-plate photovoltaic arrays and to deriving analysis and design tools necessary to achieve module designs with a 30-year useful life. The considerable progress to date stemming from the ongoing reliability research is discussed, and the major areas requiring continued research are highlighted. The result is an overview of the total array reliability problem and of available means of achieving high reliability at minimum cost.

Optimization of single channel glazed photovoltaic thermal (PVT) array using Evolutionary Algorithm (EA) and carbon credit earned by the optimized array

International Nuclear Information System (INIS)

Singh, Sonveer; Agrawal, Sanjay; Gadh, Rajit

2015-01-01

Highlights: • Optimization of SCGPVT array using Evolutionary Algorithm. • The overall exergy gain is maximized with an Evolutionary Algorithm. • Annual Performance has been evaluated for New Delhi (India). • There are improvement in results than the model given in literature. • Carbon credit analysis has been done. - Abstract: In this paper, work is carried out in three steps. In the first step, optimization of single channel glazed photovoltaic thermal (SCGPVT) array has been done with an Evolutionary Algorithm (EA) keeping the overall exergy gain is an objective function of the SCGPVT array. For maximization of overall exergy gain, total seven design variables have been optimized such as length of the channel (L), mass flow rate of flowing fluid (m_F), velocity of flowing fluid (V_F), convective heat transfer coefficient through the tedlar (U_T), overall heat transfer coefficient between solar cell to ambient through glass cover (U_S_C_A_G), overall back loss heat transfer coefficient from flowing fluid to ambient (U_F_A) and convective heat transfer coefficient of tedlar (h_T). It has been observed that the instant overall exergy gain obtained from optimized system is 1.42 kW h, which is 87.86% more than the overall exergy gain of a un-optimized system given in literature. In the second step, overall exergy gain and overall thermal gain of SCGPVT array has been evaluated annually and there are 69.52% and 88.05% improvement in annual overall exergy gain and annual overall thermal gain respectively than the un-optimized system for the same input irradiance and ambient temperature. In the third step, carbon credit earned by the optimized SCGPVT array has also been evaluated as per norms of Kyoto Protocol Bangalore climatic conditions.

Enhanced photovoltaic performance of fully flexible dye-sensitized solar cells based on the Nb{sub 2}O{sub 5} coated hierarchical TiO{sub 2} nanowire-nanosheet arrays

Energy Technology Data Exchange (ETDEWEB)

Liu, Wenwu; Hong, Chengxun; Wang, Hui-gang; Zhang, Mei; Guo, Min, E-mail: guomin@ustb.edu.cn

2016-02-28

Graphical abstract: Nb{sub 2}O{sub 5} coated hierarchical TiO{sub 2} nanowire-sheet arrays photoanode was synthesized on Ti-mesh substrate by using a hydrothermal approach for fully flexible dye-sensitized solar cells which exhibited well photovoltaic efficiency of 4.55%. - Highlights: • Nb{sub 2}O{sub 5} coated hierarchical TiO{sub 2} nanowire-nanosheet arrays were prepared on Ti-mesh. • Nb{sub 2}O{sub 5} coated TiO{sub 2} HNWAs/Pt-ITO-PEN flexible DSSC was constructed. • The fully flexible DSSC exhibited an enhanced photovoltaic performance of 4.55%. • The reasons for the improved conversion efficiency of the DSSC were discussed. - Abstract: Nb{sub 2}O{sub 5} coated hierarchical TiO{sub 2} nanowire-sheet arrays photoanode was synthesized on flexible Ti-mesh substrate by using a hydrothermal approach. The effect of TiO{sub 2} morphology and Nb{sub 2}O{sub 5} coating layer on the photovoltaic performance of the flexible dye sensitized solar cells (DSSCs) based on Ti-mesh supported nanostructures were systematically investigated. Compared to the TiO{sub 2} nanowire arrays (NWAs), hierarchical TiO{sub 2} nanowire arrays (HNWAs) with enlarged internal surface area and strong light scattering properties exhibited higher overall conversion efficiency. The introduction of thin Nb{sub 2}O{sub 5} coating layers on the surface of the TiO{sub 2} HNWAs played a key role in improving the photovoltaic performance of the flexible DSSC. By separating the TiO{sub 2} and electrolyte (I{sup –}/I{sub 3}{sup –}), the Nb{sub 2}O{sub 5} energy barrier decreased the electron recombination rate and increased electron collection efficiency and injection efficiency, resulting in improved J{sub sc} and V{sub oc}. Furthermore, the influence of Nb{sub 2}O{sub 5} coating amounts on the power conversion efficiency were discussed in detail. The fully flexible DSSC based on Nb{sub 2}O{sub 5} coated TiO{sub 2} HNWAs films with a thickness of 14 μm displayed a well photovoltaic property

Solar Radiation on Mars: Tracking Photovoltaic Array

Science.gov (United States)

Appelbaum, Joseph; Flood, Dennis J.; Crutchik, Marcos

1994-01-01

A photovoltaic power source for surface-based operation on Mars can offer many advantages. Detailed information on solar radiation characteristics on Mars and the insolation on various types of collector surfaces are necessary for effective design of future planned photovoltaic systems. In this article we have presented analytical expressions for solar radiation calculation and solar radiation data for single axis (of various types) and two axis tracking surfaces and compared the insulation to horizontal and inclined surfaces. For clear skies (low atmospheric dust load) tracking surfaces resulted in higher insolation than stationary surfaces, whereas for highly dusty atmospheres, the difference is small. The insolation on the different types of stationary and tracking surfaces depend on latitude, season and optical depth of the atmosphere, and the duration of system operation. These insolations have to be compared for each mission.

The status of lightweight photovoltaic space array technology based on amorphous silicon solar cells

Science.gov (United States)

Hanak, Joseph J.; Kaschmitter, Jim

1991-01-01

Ultralight, flexible photovoltaic (PV) array of amorphous silicon (a-Si) was identified as a potential low cost power source for small satellites. A survey was conducted of the status of the a-Si PV array technology with respect to present and future performance, availability, cost, and risks. For existing, experimental array blankets made of commercial cell material, utilizing metal foil substrates, the Beginning of Life (BOL) performance at Air Mass Zero (AM0) and 35 C includes total power up to 200 W, power per area of 64 W/sq m and power per weight of 258 W/kg. Doubling of power per weight occurs when polyimide substrates are used. Estimated End of Life (EOL) power output after 10 years in a nominal low earth orbit would be 80 pct. of BOL, the degradation being due to largely light induced effects (-10 to -15 pct.) and in part (-5 pct.) to space radiation. Predictions for the year 1995 for flexible PV arrays, made on the basis of published results for rigid a-Si modules, indicate EOL power output per area and per weight of 105 W/sq m and 400 W/kg, respectively, while predictions for the late 1990s based on existing U.S. national PV program goals indicate EOL values of 157 W/sq m and 600 W/kg. Cost estimates by vendors for 200 W ultralight arrays in volume of over 1000 units range from $100/watt to $125/watt. Identified risks include the lack of flexible, space compatible encapsulant, the lack of space qualification effort, recent partial or full acquisitions of US manufacturers of a-Si cells by foreign firms, and the absence of a national commitment for a long range development program toward developing of this important power source for space.

Reduction of intensity variations on a photovoltaic array with compound parabolic concentrators

Science.gov (United States)

Greenman, P.; Ogallagher, J.; Winston, R.; Costogue, E.

1979-01-01

The reduction of nonuniformities in the intensity distribution of light focused on a photovoltaic array by a compound parabolic concentrator is investigated. The introduction of small distortions into the surfaces of the reflector in order to diffuse the incident collimated light to fill the angular acceptance of the concentrator is calculated by means of ray tracing to decrease the irradiance nonuniformity at the cost of a lowered effective concentration of the concentrator. Measurements of the intensity distribution on a scale test model in terrestrial sunlight with corrugated aluminized mylar reflectors are shown to be in good agreement with the ray tracing results. A two-stage concentrator consisting of a focusing primary and a nonimaging secondary is also shown to result in a fairly uniform intensity distribution except in the case of a 4-deg incidence angle, which may be corrected by the introduction of distortions into one or both concentration stages.

NASA-OAST program in photovoltaic energy conversion

Science.gov (United States)

Mullin, J. P.; Flood, D. J.

1982-01-01

The NASA program in photovoltaic energy conversion includes research and technology development efforts on solar cells, blankets, and arrays. The overall objectives are to increase conversion efficiency, reduce mass, reduce cost, and increase operating life. The potential growth of space power requirements in the future presents a major challenge to the current state of technology in space photovoltaic systems.

Directory of French photovoltaic research and industry 2011

International Nuclear Information System (INIS)

Poubeau, Romain; Simmonet, Raphael; Canals, Jonathan

2011-05-01

After an overview of what is at stake in terms of industrial employment in the photovoltaic sector, a presentation of competitiveness clusters, a description of the value chain (cell manufacturers, arrays manufacturers, power inverter manufacturers, electric equipment manufacturers, structure component manufacturers, fabrication steps, etc.) in the photovoltaic sector, this document proposes a directory (addresses, activity descriptions) of research and industrial actors of the photovoltaic sector in France: research centres, manufacturers, industrial projects

Photovoltaic venture analysis. Final report. Volume III. Appendices

Energy Technology Data Exchange (ETDEWEB)

Costello, D.; Posner, D.; Schiffel, D.; Doane, J.; Bishop, C.

1978-07-01

This appendix contains a brief summary of a detailed description of alternative future energy scenarios which provide an overall backdrop for the photovoltaic venture analysis. Also included is a summary of a photovoltaic market/demand workshop, a summary of a photovoltaic supply workshop which used cross-impact analysis, and a report on photovoltaic array and system prices in 1982 and 1986. The results of a sectorial demand analysis for photovoltaic power systems used in the residential sector (single family homes), the service, commercial, and institutional sector (schools), and in the central power sector are presented. An analysis of photovoltaics in the electric utility market is given, and a report on the industrialization of photovoltaic systems is included. A DOE information memorandum regarding ''A Strategy for a Multi-Year Procurement Initiative on Photovoltaics (ACTS No. ET-002)'' is also included. (WHK)

26+ Year Old Photovoltaic Power Plant: Degradation and Reliability Evaluation of Crystalline Silicon Modules -- South Array

Science.gov (United States)

Olakonu, Kolapo

As the use of photovoltaic (PV) modules in large power plants continues to increase globally, more studies on degradation, reliability, failure modes, and mechanisms of field aged modules are needed to predict module life expectancy based on accelerated lifetime testing of PV modules. In this work, a 26+ year old PV power plant in Phoenix, Arizona has been evaluated for performance, reliability, and durability. The PV power plant, called Solar One, is owned and operated by John F. Long's homeowners association. It is a 200 kW dc, standard test conditions (STC) rated power plant comprised of 4000 PV modules or frameless laminates, in 100 panel groups (rated at 175 kW ac). The power plant is made of two center-tapped bipolar arrays, the north array and the south array. Due to a limited time frame to execute this large project, this work was performed by two masters students (Jonathan Belmont and Kolapo Olakonu) and the test results are presented in two masters theses. This thesis presents the results obtained on the south array and the other thesis presents the results obtained on the north array. Each of these two arrays is made of four sub arrays, the east sub arrays (positive and negative polarities) and the west sub arrays (positive and negative polarities), making up eight sub arrays. The evaluation and analyses of the power plant included in this thesis consists of: visual inspection, electrical performance measurements, and infrared thermography. A possible presence of potential induced degradation (PID) due to potential difference between ground and strings was also investigated. Some installation practices were also studied and found to contribute to the power loss observed in this investigation. The power output measured in 2011 for all eight sub arrays at STC is approximately 76 kWdc and represents a power loss of 62% (from 200 kW to 76 kW) over 26+ years. The 2011 measured power output for the four south sub arrays at STC is 39 kWdc and represents a power

Performance analysis of solar cell arrays in concentrating light intensity

International Nuclear Information System (INIS)

Xu Yongfeng; Li Ming; Lin Wenxian; Wang Liuling; Xiang Ming; Zhang Xinghua; Wang Yunfeng; Wei Shengxian

2009-01-01

Performance of concentrating photovoltaic/thermal system is researched by experiment and simulation calculation. The results show that the I-V curve of the GaAs cell array is better than that of crystal silicon solar cell arrays and the exergy produced by 9.51% electrical efficiency of the GaAs solar cell array can reach 68.93% of the photovoltaic/thermal system. So improving the efficiency of solar cell arrays can introduce more exergy and the system value can be upgraded. At the same time, affecting factors of solar cell arrays such as series resistance, temperature and solar irradiance also have been analyzed. The output performance of a solar cell array with lower series resistance is better and the working temperature has a negative impact on the voltage in concentrating light intensity. The output power has a -20 W/V coefficient and so cooling fluid must be used. Both heat energy and electrical power are then obtained with a solar trough concentrating photovoltaic/thermal system. (semiconductor devices)

Operation and maintenance cost data for residential photovoltaic modules/panels

Science.gov (United States)

Oster, J. R., Jr.; Zaremski, D. R., Jr.; Albert, E. M.; Hawkins, S. L.

1980-01-01

Costs associated with the operation and maintenance of residential photovoltaic modules and arrays are studied. Six basic topics related to operation and maintenance to photovoltaic arrays are investigated: maintenance; cleaning; panel replacement; gasket repair/replacement; wiring repair/replacement; and termination repair/replacement. The effects of the mounting types (rack mount, stand off mount, direct mount and integral mount) and the installation/replacement type (sequential, partial interruption and independent) are identified and described. Methods of reducing maintenance costs are suggested.

Particle Swarm Optimization Based of the Maximum Photovoltaic ...

African Journals Online (AJOL)

Photovoltaic electricity is seen as an important source of renewable energy. The photovoltaic array is an unstable source of power since the peak power point depends on the temperature and the irradiation level. A maximum peak power point tracking is then necessary for maximum efficiency. In this work, a Particle Swarm ...

Core-shell heterojunction of silicon nanowire arrays and carbon quantum dots for photovoltaic devices and self-driven photodetectors.

Science.gov (United States)

Xie, Chao; Nie, Biao; Zeng, Longhui; Liang, Feng-Xia; Wang, Ming-Zheng; Luo, Linbao; Feng, Mei; Yu, Yongqiang; Wu, Chun-Yan; Wu, Yucheng; Yu, Shu-Hong

2014-04-22

Silicon nanostructure-based solar cells have lately intrigued intensive interest because of their promising potential in next-generation solar energy conversion devices. Herein, we report a silicon nanowire (SiNW) array/carbon quantum dot (CQD) core-shell heterojunction photovoltaic device by directly coating Ag-assisted chemical-etched SiNW arrays with CQDs. The heterojunction with a barrier height of 0.75 eV exhibited excellent rectifying behavior with a rectification ratio of 10(3) at ±0.8 V in the dark and power conversion efficiency (PCE) as high as 9.10% under AM 1.5G irradiation. It is believed that such a high PCE comes from the improved optical absorption as well as the optimized carrier transfer and collection capability. Furthermore, the heterojunction could function as a high-performance self-driven visible light photodetector operating in a wide switching wavelength with good stability, high sensitivity, and fast response speed. It is expected that the present SiNW array/CQD core-shell heterojunction device could find potential applications in future high-performance optoelectronic devices.

Optimizing the design of preprinted orders for ambulatory chemotherapy: combining oncology, human factors, and graphic design.

Science.gov (United States)

Jeon, Jennifer; White, Rachel E; Hunt, Richard G; Cassano-Piché, Andrea L; Easty, Anthony C

2012-03-01

To establish a set of guidelines for developing ambulatory chemotherapy preprinted orders. Multiple methods were used to develop the preprinted order guidelines. These included (A) a comprehensive literature review and an environmental scan; (B) analyses of field study observations and incident reports; (C) critical review of evidence from the literature and the field study observation analyses; (D) review of the draft guidelines by a clinical advisory group; and (E) collaboration with graphic designers to develop sample preprinted orders, refine the design guidelines, and format the resulting content. The Guidelines for Developing Ambulatory Chemotherapy Preprinted Orders, which consist of guidance on the design process, content, and graphic design elements of ambulatory chemotherapy preprinted orders, have been established. Health care is a safety critical, dynamic, and complex sociotechnical system. Identifying safety risks in such a system and effectively addressing them often require the expertise of multiple disciplines. This study illustrates how human factors professionals, clinicians, and designers can leverage each other's expertise to uncover commonly overlooked patient safety hazards and to provide health care professionals with innovative, practical, and user-centered tools to minimize those hazards.

Photovoltaic Properties of p-Doped GaAs Nanowire Arrays Grown on n-Type GaAs(111)B Substrate

Science.gov (United States)

2010-01-01

We report on the molecular beam epitaxy growth of Au-assisted GaAs p-type-doped NW arrays on the n-type GaAs(111)B substrate and their photovoltaic properties. The samples are grown at different substrate temperature within the range from 520 to 580 °C. It is shown that the dependence of conversion efficiency on the substrate temperature has a maximum at the substrate temperature of 550 °C. For the best sample, the conversion efficiency of 1.65% and the fill factor of 25% are obtained. PMID:20672038

Optimizing electrical load pattern in Kuwait using grid connected photovoltaic systems

International Nuclear Information System (INIS)

Al-Hasan, A.Y.; Ghoneim, A.A.; Abdullah, A.H.

2004-01-01

Grid connected photovoltaic systems is one of the most promising applications of photovoltaic systems. These systems are employed in applications where utility service is already available. In this case, there is no need for battery storage because grid power may be used to supplement photovoltaic systems (PV) when the load exceeds available PV generation. The load receives electricity from both the photovoltaic array and the utility grid. In this system, the load is the total electrical energy consumption. The main objective of the present work is to optimize the electrical load pattern in Kuwait using grid connected PV systems. In this situation, the electric load demand can be satisfied from both the photovoltaic array and the utility grid. The performance of grid connected photovoltaic systems in the Kuwait climate has been evaluated. It was found that the peak load matches the maximum incident solar radiation in Kuwait, which would emphasize the role of using the PV station to minimize the electrical load demand. In addition, a significant reduction in peak load can be achieved with grid connected PV systems

Development of a Photovoltaic Array Emulator System in Real Time Considering Climatic Conditions Variations

Directory of Open Access Journals (Sweden)

Camilo E. Ardila-Franco

2013-11-01

Full Text Available This paper presents the development of an emulator that has the ability to replicate, in real time, the behavior of photovoltaic panels (PV arrays considering different conditions of irradiation and temperature for each one. The emulator consists of a data acquisition card, a programmable source and a computer. It is based on the bypass diode model that provides a better approximation to real operating conditions. The solution is computed by a simplified equation that uses the Lambert W function, which reduces the computation time. After that, it generates a solution table of values of current as a function of voltage on terminals, temperature and irradiation. Real-time emulation is performed by means of a search algorithm in the solutions table of the closest value to the voltage imposed on the terminals.

Spectroradiometer Intercomparison and Impact on Characterizing Photovoltaic Device Performance: Preprint

Energy Technology Data Exchange (ETDEWEB)

Habte, A.; Andreas, A.; Ottoson, L.; Gueymard, C.; Fedor, G.; Fowler, S.; Peterson, J.; Naranen, E.; Kobashi, T.; Akiyama, A.; Takagi, S.

2014-11-01

Indoor and outdoor testing of photovoltaic (PV) device performance requires the use of solar simulators and natural solar radiation, respectively. This performance characterization requires accurate knowledge of spectral irradiance distribution that is incident on the devices. Spectroradiometers are used to measure the spectral distribution of solar simulators and solar radiation. On September 17, 2013, a global spectral irradiance intercomparison using spectroradiometers was organized by the Solar Radiation Research Laboratory (SRRL) at the National Renewable Energy Laboratory (NREL). This paper presents highlights of the results of this first intercomparison, which will help to decrease systematic inter-laboratory differences in the measurements of the outputs or efficiencies of PV devices and harmonize laboratory experimental procedures.

Adaptive smart simulator for characterization and MPPT construction of PV array

International Nuclear Information System (INIS)

Ouada, Mehdi; Meridjet, Mohamed Salah; Dib, Djalel

2016-01-01

Partial shading conditions are among the most important problems in large photovoltaic array. Many works of literature are interested in modeling, control and optimization of photovoltaic conversion of solar energy under partial shading conditions, The aim of this study is to build a software simulator similar to hard simulator and to produce a shading pattern of the proposed photovoltaic array in order to use the delivered information to obtain an optimal configuration of the PV array and construct MPPT algorithm. Graphical user interfaces (Matlab GUI) are built using a developed script, this tool is easy to use, simple, and has a rapid of responsiveness, the simulator supports large array simulations that can be interfaced with MPPT and power electronic converters.

Adaptive smart simulator for characterization and MPPT construction of PV array

Science.gov (United States)

Ouada, Mehdi; Meridjet, Mohamed Salah; Dib, Djalel

2016-07-01

Partial shading conditions are among the most important problems in large photovoltaic array. Many works of literature are interested in modeling, control and optimization of photovoltaic conversion of solar energy under partial shading conditions, The aim of this study is to build a software simulator similar to hard simulator and to produce a shading pattern of the proposed photovoltaic array in order to use the delivered information to obtain an optimal configuration of the PV array and construct MPPT algorithm. Graphical user interfaces (Matlab GUI) are built using a developed script, this tool is easy to use, simple, and has a rapid of responsiveness, the simulator supports large array simulations that can be interfaced with MPPT and power electronic converters.

Adaptive smart simulator for characterization and MPPT construction of PV array

Energy Technology Data Exchange (ETDEWEB)

Ouada, Mehdi, E-mail: mehdi.ouada@univ-annaba.org; Meridjet, Mohamed Salah [Electromechanical engineering department, Electromechanical engineering laboratory, Badji Mokhtar University, B.P. 12, Annaba (Algeria); Dib, Djalel [Department of Electrical Engineering, University of Tebessa, Tebessa (Algeria)

2016-07-25

Partial shading conditions are among the most important problems in large photovoltaic array. Many works of literature are interested in modeling, control and optimization of photovoltaic conversion of solar energy under partial shading conditions, The aim of this study is to build a software simulator similar to hard simulator and to produce a shading pattern of the proposed photovoltaic array in order to use the delivered information to obtain an optimal configuration of the PV array and construct MPPT algorithm. Graphical user interfaces (Matlab GUI) are built using a developed script, this tool is easy to use, simple, and has a rapid of responsiveness, the simulator supports large array simulations that can be interfaced with MPPT and power electronic converters.

NASA-OAST photovoltaic energy conversion program

Science.gov (United States)

Mullin, J. P.; Loria, J. C.

1984-01-01

The NASA program in photovoltaic energy conversion research is discussed. Solar cells, solar arrays, gallium arsenides, space station and spacecraft power supplies, and state of the art devices are discussed.

Life Prediction Model for Grid-Connected Li-ion Battery Energy Storage System: Preprint

Energy Technology Data Exchange (ETDEWEB)

Smith, Kandler A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Saxon, Aron R [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Keyser, Matthew A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Lundstrom, Blake R [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Cao, Ziwei [SunPower Corporation; Roc, Albert [SunPower Corp.

2017-08-25

Life Prediction Model for Grid-Connected Li-ion Battery Energy Storage System: Preprint Lithium-ion (Li-ion) batteries are being deployed on the electrical grid for a variety of purposes, such as to smooth fluctuations in solar renewable power generation. The lifetime of these batteries will vary depending on their thermal environment and how they are charged and discharged. To optimal utilization of a battery over its lifetime requires characterization of its performance degradation under different storage and cycling conditions. Aging tests were conducted on commercial graphite/nickel-manganese-cobalt (NMC) Li-ion cells. A general lifetime prognostic model framework is applied to model changes in capacity and resistance as the battery degrades. Across 9 aging test conditions from 0oC to 55oC, the model predicts capacity fade with 1.4 percent RMS error and resistance growth with 15 percent RMS error. The model, recast in state variable form with 8 states representing separate fade mechanisms, is used to extrapolate lifetime for example applications of the energy storage system integrated with renewable photovoltaic (PV) power generation.

Fuzzy Controller Design Using FPGA for Photovoltaic Maximum Power Point Tracking

OpenAIRE

Basil M Hamed; Mohammed S. El-Moghany

2012-01-01

The cell has optimum operating point to be able to get maximum power. To obtain Maximum Power from photovoltaic array, photovoltaic power system usually requires Maximum Power Point Tracking (MPPT) controller. This paper provides a small power photovoltaic control system based on fuzzy control with FPGA technology design and implementation for MPPT. The system composed of photovoltaic module, buck converter and the fuzzy logic controller implemented on FPGA for controlling on/off time of MOSF...

Photovoltaic restoration of sight with high visual acuity

Science.gov (United States)

Lorach, Henri; Goetz, Georges; Smith, Richard; Lei, Xin; Mandel, Yossi; Kamins, Theodore; Mathieson, Keith; Huie, Philip; Harris, James; Sher, Alexander; Palanker, Daniel

2015-01-01

Patients with retinal degeneration lose sight due to gradual demise of photoreceptors. Electrical stimulation of the surviving retinal neurons provides an alternative route for delivery of visual information. We demonstrate that subretinal arrays with 70 μm photovoltaic pixels provide highly localized stimulation, with electrical and visual receptive fields of comparable sizes in rat retinal ganglion cells. Similarly to normal vision, retinal response to prosthetic stimulation exhibits flicker fusion at high frequencies, adaptation to static images and non-linear spatial summation. In rats with retinal degeneration, these photovoltaic arrays provide spatial resolution of 64 ± 11 μm, corresponding to half of the normal visual acuity in pigmented rats. Ease of implantation of these wireless and modular arrays, combined with their high resolution opens the door to functional restoration of sight. PMID:25915832

An inverter/controller subsystem optimized for photovoltaic applications

Science.gov (United States)

Pickrell, R. L.; Merrill, W. C.; Osullivan, G.

1978-01-01

Conversion of solar array dc power to ac power stimulated the specification, design, and simulation testing of an inverter/controller subsystem tailored to the photovoltaic power source characteristics. This paper discusses the optimization of the inverter/controller design as part of an overall Photovoltaic Power System (PPS) designed for maximum energy extraction from the solar array. The special design requirements for the inverter/controller include: (1) a power system controller (PSC) to control continuously the solar array operating point at the maximum power level based on variable solar insolation and cell temperatures; and (2) an inverter designed for high efficiency at rated load and low losses at light loadings to conserve energy. It must be capable of operating connected to the utility line at a level set by an external controller (PSC).

NASA advanced space photovoltaic technology-status, potential and future mission applications

Science.gov (United States)

Flood, Dennis J.; Piszczor, Michael, Jr.; Stella, Paul M.; Bennett, Gary L.

1989-01-01

The NASA program in space photovoltaic research and development encompasses a wide range of emerging options for future space power systems, and includes both cell and array technology development. The long range goals are to develop technology capable of achieving 300 W/kg for planar arrays, and 300 W/sq m for concentrator arrays. InP and GaAs planar and concentrator cell technologies are under investigation for their potential high efficiency and good radiation resistance. The Advanced Photovoltaic Solar Array (APSA) program is a near term effort aimed at demonstrating 130 W/kg beginning of life specific power using thin (62 micrometer) silicon cells. It is intended to be technology transparent to future high efficiency cells and provides the baseline for development of the 300 W/kg array.

Microsystem enabled photovoltaic modules and systems

Energy Technology Data Exchange (ETDEWEB)

Nielson, Gregory N.; Sweatt, William C.; Okandan, Murat

2017-09-12

A photovoltaic (PV) module includes an absorber layer coupled to an optic layer. The absorber layer includes an array of PV elements. The optic layer includes a close-packed array of Keplerian telescope elements, each corresponding to one of an array of pupil elements. The Keplerian telescope substantially couple radiation that is incident on their objective surfaces into the corresponding pupil elements. Each pupil element relays radiation that is coupled into it from the corresponding Keplerian telescope element into the corresponding PV element.

An initial analysis of options for a UK feed-in tariff for photovoltaic energy, from an array owner's viewpoint

International Nuclear Information System (INIS)

Plater, Steve

2009-01-01

The UK government has announced the introduction from April 2010 of a feed-in tariff (FIT) for renewable energy, and initiated a consultation on its design. This paper compares three possible variants of a UK FIT for rooftop photovoltaic (PV) arrays, on the basis of calculated income and array cost payback time, and for three locations (north, central and southern England) and various levels of household electricity consumption. This modelling is based on an FIT rate equivalent to Germany's. It concludes that an FIT which paid only for PV electricity surplus to on-site needs, and exported to the grid, would mean a simple payback time too long to make array purchase appealing. Preferable would be either export to the grid of all PV electricity for FIT payment; or a lower FIT rate for electricity used on-site, plus full FIT for any surplus exported. The latter would involve significantly lower costs in feed-in tariff payments. Finally, the effect of the UK government's illustrative FIT rate for consultation is examined for the same locations and annual consumption levels.

Centralized and Modular Architectures for Photovoltaic Panels with Improved Efficiency: Preprint

Energy Technology Data Exchange (ETDEWEB)

Dhakal, B.; Mancilla-David, F.; Muljadi, E.

2012-07-01

The most common type of photovoltaic installation in residential applications is the centralized architecture, but the performance of a centralized architecture is adversely affected when it is subject to partial shading effects due to clouds or surrounding obstacles, such as trees. An alternative modular approach can be implemented using several power converters with partial throughput power processing capability. This paper presents a detailed study of these two architectures for the same throughput power level and compares the overall efficiencies using a set of rapidly changing real solar irradiance data collected by the Solar Radiation Research Laboratory at the National Renewable Energy Laboratory.

Low earth orbit environmental effects on the space station photovoltaic power generation systems

International Nuclear Information System (INIS)

Nahra, H.K.

1977-01-01

A summary of the Low Earth Orbital Environment, its impact on the photovoltaic power systems of the space station and the solutions implemented to resolve the environmental concerns or issues are described. Low Earth Orbital Environment (LEO) presents several concerns to the photovoltaic power systems of the space station. These concerns include atomic oxygen interaction with the polymeric substrate of the solar arrays, ionized environment effects on the array operating voltage, the effects of the meteoroids and debris impacts and penetration through the different layers of the solar cells and their circuits, and the high energy particle and radiation effects on the overall solar array performance. Potential solutions to some of the degrading environmental interactions that will provide the photovoltaic power system of the space station with the desired life are also summarized

A distributed monitoring system for photovoltaic arrays based on a two-level wireless sensor network

Science.gov (United States)

Su, F. P.; Chen, Z. C.; Zhou, H. F.; Wu, L. J.; Lin, P. J.; Cheng, S. Y.; Li, Y. F.

2017-11-01

In this paper, a distributed on-line monitoring system based on a two-level wireless sensor network (WSN) is proposed for real time status monitoring of photovoltaic (PV) arrays to support the fine management and maintenance of PV power plants. The system includes the sensing nodes installed on PV modules (PVM), sensing and routing nodes installed on combiner boxes of PV sub-arrays (PVA), a sink node and a data management centre (DMC) running on a host computer. The first level WSN is implemented by the low-cost wireless transceiver nRF24L01, and it is used to achieve single hop communication between the PVM nodes and their corresponding PVA nodes. The second level WSN is realized by the CC2530 based ZigBee network for multi-hop communication among PVA nodes and the sink node. The PVM nodes are used to monitor the PVM working voltage and backplane temperature, and they send the acquired data to their PVA node via the nRF24L01 based first level WSN. The PVA nodes are used to monitor the array voltage, PV string current and environment irradiance, and they send the acquired and received data to the DMC via the ZigBee based second level WSN. The DMC is designed using the MATLAB GUIDE and MySQL database. Laboratory experiment results show that the system can effectively acquire, display, store and manage the operating and environment parameters of PVA in real time.

Wafer-scale high-throughput ordered arrays of Si and coaxial Si/Si(1-x)Ge(x) wires: fabrication, characterization, and photovoltaic application.

Science.gov (United States)

Pan, Caofeng; Luo, Zhixiang; Xu, Chen; Luo, Jun; Liang, Renrong; Zhu, Guang; Wu, Wenzhuo; Guo, Wenxi; Yan, Xingxu; Xu, Jun; Wang, Zhong Lin; Zhu, Jing

2011-08-23

We have developed a method combining lithography and catalytic etching to fabricate large-area (uniform coverage over an entire 5-in. wafer) arrays of vertically aligned single-crystal Si nanowires with high throughput. Coaxial n-Si/p-SiGe wire arrays are also fabricated by further coating single-crystal epitaxial SiGe layers on the Si wires using ultrahigh vacuum chemical vapor deposition (UHVCVD). This method allows precise control over the diameter, length, density, spacing, orientation, shape, pattern and location of the Si and Si/SiGe nanowire arrays, making it possible to fabricate an array of devices based on rationally designed nanowire arrays. A proposed fabrication mechanism of the etching process is presented. Inspired by the excellent antireflection properties of the Si/SiGe wire arrays, we built solar cells based on the arrays of these wires containing radial junctions, an example of which exhibits an open circuit voltage (V(oc)) of 650 mV, a short-circuit current density (J(sc)) of 8.38 mA/cm(2), a fill factor of 0.60, and an energy conversion efficiency (η) of 3.26%. Such a p-n radial structure will have a great potential application for cost-efficient photovoltaic (PV) solar energy conversion. © 2011 American Chemical Society

Performance of photovoltaic arrays in-vivo and characteristics of prosthetic vision in animals with retinal degeneration

Science.gov (United States)

Lorach, Henri; Goetz, Georges; Mandel, Yossi; Lei, Xin; Kamins, Theodore I.; Mathieson, Keith; Huie, Philip; Dalal, Roopa; Harris, James S.; Palanker, Daniel

2014-01-01

Summary Loss of photoreceptors during retinal degeneration leads to blindness, but information can be reintroduced into the visual system using electrical stimulation of the remaining retinal neurons. Subretinal photovoltaic arrays convert pulsed illumination into pulsed electric current to stimulate the inner retinal neurons. Since required irradiance exceeds the natural luminance levels, an invisible near-infrared (915nm) light is used to avoid photophobic effects. We characterized the thresholds and dynamic range of cortical responses to prosthetic stimulation with arrays of various pixel sizes and with different number of photodiodes. Stimulation thresholds for devices with 140µm pixels were approximately half those of 70µm pixels, and with both pixel sizes, thresholds were lower with 2 diodes than with 3 diodes per pixel. In all cases these thresholds were more than two orders of magnitude below the ocular safety limit. At high stimulation frequencies (>20Hz), the cortical response exhibited flicker fusion. Over one order of magnitude of dynamic range could be achieved by varying either pulse duration or irradiance. However, contrast sensitivity was very limited. Cortical responses could be detected even with only a few illuminated pixels. Finally, we demonstrate that recording of the corneal electric potential in response to patterned illumination of the subretinal arrays allows monitoring the current produced by each pixel, and thereby assessing the changes in the implant performance over time. PMID:25255990

SAM Photovoltaic Model Technical Reference 2016 Update

Energy Technology Data Exchange (ETDEWEB)

Gilman, Paul [National Renewable Energy Laboratory (NREL), Golden, CO (United States); DiOrio, Nicholas A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Freeman, Janine M [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Janzou, Steven [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Dobos, Aron [No longer NREL employee; Ryberg, David [No longer NREL employee

2018-03-19

This manual describes the photovoltaic performance model in the System Advisor Model (SAM) software, Version 2016.3.14 Revision 4 (SSC Version 160). It is an update to the 2015 edition of the manual, which describes the photovoltaic model in SAM 2015.1.30 (SSC 41). This new edition includes corrections of errors in the 2015 edition and descriptions of new features introduced in SAM 2016.3.14, including: 3D shade calculator Battery storage model DC power optimizer loss inputs Snow loss model Plane-of-array irradiance input from weather file option Support for sub-hourly simulations Self-shading works with all four subarrays, and uses same algorithm for fixed arrays and one-axis tracking Linear self-shading algorithm for thin-film modules Loss percentages replace derate factors. The photovoltaic performance model is one of the modules in the SAM Simulation Core (SSC), which is part of both SAM and the SAM SDK. SAM is a user-friedly desktop application for analysis of renewable energy projects. The SAM SDK (Software Development Kit) is for developers writing their own renewable energy analysis software based on SSC. This manual is written for users of both SAM and the SAM SDK wanting to learn more about the details of SAM's photovoltaic model.

Optical characterization of nonimaging dish concentrator for the application of dense-array concentrator photovoltaic system.

Science.gov (United States)

Tan, Ming-Hui; Chong, Kok-Keong; Wong, Chee-Woon

2014-01-20

Optimization of the design of a nonimaging dish concentrator (NIDC) for a dense-array concentrator photovoltaic system is presented. A new algorithm has been developed to determine configuration of facet mirrors in a NIDC. Analytical formulas were derived to analyze the optical performance of a NIDC and then compared with a simulated result obtained from a numerical method. Comprehensive analysis of optical performance via analytical method has been carried out based on facet dimension and focal distance of the concentrator with a total reflective area of 120 m2. The result shows that a facet dimension of 49.8 cm, focal distance of 8 m, and solar concentration ratio of 411.8 suns is the most optimized design for the lowest cost-per-output power, which is US$1.93 per watt.

Photovoltaic array performance simulation models

Energy Technology Data Exchange (ETDEWEB)

Menicucci, D. F.

1986-09-15

The experience of the solar industry confirms that, despite recent cost reductions, the profitability of photovoltaic (PV) systems is often marginal and the configuration and sizing of a system is a critical problem for the design engineer. Construction and evaluation of experimental systems are expensive and seldom justifiable. A mathematical model or computer-simulation program is a desirable alternative, provided reliable results can be obtained. Sandia National Laboratories, Albuquerque (SNLA), has been studying PV-system modeling techniques in an effort to develop an effective tool to be used by engineers and architects in the design of cost-effective PV systems. This paper reviews two of the sources of error found in previous PV modeling programs, presents the remedies developed to correct these errors, and describes a new program that incorporates these improvements.

Photovoltaic demonstration projects 2

Energy Technology Data Exchange (ETDEWEB)

Gillett, W B; Hacker, R J [Halcrow (William) and Partners, Swindon (UK); Kaut, W [eds.

1989-01-01

This book, the proceedings of the third Photovoltaic Contractors' Meeting organised by the Commission of the European Communities, Directorate-General for Energy provides an overview of the photovoltaic demonstration projects which have been supported by the Energy Directorate of the Commission of the European Communities since 1983. It includes reports by each of the contractors who submitted proposals in 1983, 1984 and 1985, describing progress with their projects. The different technologies which are being demonstrated concern the modules, the cabling of the array, structure design, storage strategy and power conditioning. The various applications include powering of houses, villages, recreation centres, water desalination, communications, dairy farms, water pumping and warning systems. (author).

Photovoltaic technologies for commercial power generation

International Nuclear Information System (INIS)

Carlson, D.E.

1990-01-01

Photovoltaic power generation is an attractive source of energy since it involves the direct conversion of sunlight into electricity with no moving parts and no pollution. Following the demonstration of the first solar cell 35 years ago at Bell Laboratories, a steady stream of scientific and commercial progress has led to a rapid increase in applications in recent years. The first commercial application of solar cells occurred more than 20 years ago when they were used to supply power for space satellites, and even today photovoltaic arrays are used to supply electricity for most satellites and space probes. This paper reviews the status of the various photovoltaic technologies as well as present applications. The prospects for both distributed and central station grid-connected systems are discussed. The paper concludes with a discussion of the institutional and political factors that will affect the introduction of grid-connected photovoltaic power systems

Photovoltaic Test and Demonstration Project. [for solar cell power systems

Science.gov (United States)

Forestieri, A. F.; Brandhorst, H. W., Jr.; Deyo, J. N.

1976-01-01

The Photovoltaic Test and Demonstration Project was initiated by NASA in June, 1975, to develop economically feasible photovoltaic power systems suitable for a variety of terrestrial applications. Objectives include the determination of operating characteristic and lifetimes of a variety of solar cell systems and components and development of methodology and techniques for accurate measurements of solar cell and array performance and diagnostic measurements for solar power systems. Initial work will be concerned with residential applications, with testing of the first prototype system scheduled for June, 1976. An outdoor 10 kW array for testing solar power systems is under construction.

Temperature-sensitive junction transformations for mid-wavelength HgCdTe photovoltaic infrared detector arrays by laser beam induced current microscope

Energy Technology Data Exchange (ETDEWEB)

Qiu, Weicheng [College of Photoelectric Science and Engineering, National University of Defense Technology, Changsha, Hunan 410073 (China); National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083 (China); Hu, Weida, E-mail: wdhu@mail.sitp.ac.cn; Lin, Tie; Yin, Fei; Zhang, Bo; Chen, Xiaoshuang; Lu, Wei [National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083 (China); Cheng, Xiang' ai, E-mail: xiang-ai-cheng@126.com; Wang, Rui [College of Photoelectric Science and Engineering, National University of Defense Technology, Changsha, Hunan 410073 (China)

2014-11-10

In this paper, we report on the disappearance of the photosensitive area extension effect and the unusual temperature dependence of junction transformation for mid-wavelength, n-on-p HgCdTe photovoltaic infrared detector arrays. The n-type region is formed by B{sup +} ion implantation on Hg-vacancy-doped p-type HgCdTe. Junction transformations under different temperatures are visually captured by a laser beam induced current microscope. A physical model of temperature dependence on junction transformation is proposed and demonstrated by using numerical simulations. It is shown that Hg-interstitial diffusion and temperature activated defects jointly lead to the p-n junction transformation dependence on temperature, and the weaker mixed conduction compared with long-wavelength HgCdTe photodiode contributes to the disappearance of the photosensitive area extension effect in mid-wavelength HgCdTe infrared detector arrays.

Flat-plate solar array project. Volume 1: Executive summary

Science.gov (United States)

Callaghan, W.; Mcdonald, R.

1986-01-01

In 1975, the U.S. Government contracted the Jet Propulsion Lab. to develop, by 1985, in conjunction with industry, the photovoltaics (PV) module and array technology required for widespread use of photovoltaics as a significant terrestrial energy source. As a result, a project that eventually became known as the Flat Plate Solar Array (FSA) Project was formed to manage an industry, university, and Government team to perform the necessary research and development. The original goals were to achieve widespread commercial use of PV modules and arrays through the development of technology that would allow them to be profitably sold for $1.07/peak watts (1985 dollars). A 10% module conversion efficiency and a 20 year lifetime were also goals. It is intended that the executive summary provide the means by which one can gain a perspective on 11 years of terrestrial photovoltaic research and development conducted by the FSA Project.

MOD silver metallization for photovoltaics

Science.gov (United States)

Vest, G. M.; Vest, R. W.

1984-01-01

The development of flat plate solar arrays is reported. Photovoltaic cells require back side metallization and a collector grid system on the front surface. Metallo-organic decomposition (MOD) silver films can eliminate most of the present problems with silver conductors. The objectives are to: (1) identify and characterize suitable MO compounds; (2) develop generic synthesis procedures for the MO compounds; (3) develop generic fabrication procedures to screen printable MOD silver inks; (4) optimize processing conditions to produce grid patterns and photovoltaic cells; and (5) develop a model which describes the adhesion between the fired silver film and the silicon surface.

Output characteristics of 40 kW photovoltaic power generation system in ICT; Ibaraki kosen ni okeru 40 kW taiyoko hatsuden shisutemu no shutsuryoku tokusei

Energy Technology Data Exchange (ETDEWEB)

Sekiguchi, N. [Ibaraki National College of Tech., Ibaraki (Japan); Tani, T. [Science University of Tokyo, Tokyo (Japan)

1999-11-25

The photovoltaic power generation system consists of photovoltaic array and power conditioner of the utility connected system. The photovoltaic array parallelly constitutes 18 serial 30 of the modules of 540 sheets, and there is the generating capacity of largest 40 kW. The power conditioner uses 10 kW four units, and it is tracking with function of the maximum output point. This report examined the unconformable rate of photovoltaic array maximum output operating voltage, current and power in simulation and power conditioner input. (author)

Customizable pre-printed consent forms: a solution in light of the Montgomery ruling.

Science.gov (United States)

Owen, Deborah; Aresti, Nick; Mulligan, Alex; Kosuge, Dennis

2018-02-02

This article presents an audit cycle supported quality improvement project addressing best practice in the consent process for lower limb arthroplasty which takes into account the new standard in surgical consent and the importance of material risks. 50 consecutive total hip and total knee replacement consent forms over a 3-month period were reviewed for legibility and completeness. Following the introduction of a new, pre-printed but customizable consent form the review process was repeated. The introduction of a customizable, pre-printed consent form that can be adjusted to reflect the individualized material risks of each patient increased legibility, reduced inappropriate human error variation and abolished the use of abbreviations and medical jargon. When used as part of an extended consent process, the authors feel that the use of pre-printed but customizable consent forms improves legibility, completeness and consistency and also provides the ability to highlight those complications that are of particular importance for that patient to satisfy the new accepted standard in surgical consent.

Commercial Application of a Photovoltaic Concentrator system. Phase I. Final report, 1 June 1978-28 February 1979

Energy Technology Data Exchange (ETDEWEB)

Anderson, D.J.; Anderson, E.R.; Bardwell, K.M.

1980-04-01

This report documents the design and analysis of the BDM CAPVC (Commercial Application of a Photovoltaic Concentrator) system. The preliminary design, prototype test and evaluation, system analysis, and final design of a large-scale concentrating photovoltaic system are described. The application is on an attractive new office building which represents a large potential market. The photovoltaic concentrating array is a roof-mounted, single-axis linear parabolic trough, using single crystalline silicon photovoltaic cells. A total of 6720 square feet of aperture is focussed on 13,944 PV cells. The photovoltaic system operates in parallel with the local utility in an augmentary loadsharing operating mode. The array is actively cooled and the thermal energy utilized for building heat during winter months. (WHK)

Arrays of ZnO/CuIn{sub x}Ga{sub 1−x}Se{sub 2} nanocables with tunable shell composition for efficient photovoltaics

Energy Technology Data Exchange (ETDEWEB)

Akram, Muhammad Aftab; Javed, Sofia [Center of Super-Diamond and Advanced Films (COSDAF), Department of Physics and Materials Science, City University of Hong Kong, Hong Kong (Hong Kong); City University of Hong Kong, Shenzhen Research Institute, Shenzhen 518057 (Hong Kong); School of Chemical and Materials Engineering, National University of Sciences and Technology, Sector H-12, Islamabad 44000 (Pakistan); Xu, Jun, E-mail: apjunxu@hfut.edu.cn [School of Electronic Science and Applied Physics, Hefei University of Technology, Hefei 230009 (China); Mujahid, Mohammad, E-mail: principal@scme.nust.edu.pk [School of Chemical and Materials Engineering, National University of Sciences and Technology, Sector H-12, Islamabad 44000 (Pakistan); Lee, Chun-Sing, E-mail: c.s.lee@cityu.edu.hk [Center of Super-Diamond and Advanced Films (COSDAF), Department of Physics and Materials Science, City University of Hong Kong, Hong Kong (Hong Kong); City University of Hong Kong Shenzhen Research Institute, Shenzhen 518057 (Hong Kong)

2015-05-28

Arrays of one-dimensional (1D) nanostructure are receiving much attention for their optoelectronic and photovoltaic applications due to their advantages in light absorption, charge separation, and transportation. In this work, arrays of ZnO/CuIn{sub x}Ga{sub 1−x}Se{sub 2} core/shell nanocables with tunable shell compositions over the full range of 0 ≤ x ≤ 1 have been controllably synthesized. Chemical conversions of ZnO nanorods to a series of ZnO-based nanocables, including ZnO/ZnSe, ZnO/CuSe, ZnO/CuSe/In{sub x}Ga{sub 1−x}, ZnO/CuSe/(In{sub x}Ga{sub 1−x}){sub 2}Se{sub 3}, and ZnO/CuIn{sub x}Ga{sub 1−x}Se{sub 2}, are well designed and successfully achieved. Composition-dependent influences of the CuIn{sub x}Ga{sub 1−x}Se{sub 2} shells on photovoltaic performance are investigated. It is found that the increase in indium content (x) leads to an increase in short-circuit current density (J{sub SC}) but a decrease in open-circuit voltage (V{sub OC}) for the ZnO/CuIn{sub x}Ga{sub 1−x}Se{sub 2} nanocable solar cells. An array of ZnO/CuIn{sub 0.67}Ga{sub 0.33}Se{sub 2} nanocables with a length of ∼1 μm and a shell thickness of ∼10 nm exhibits a bandgap of 1.20 eV, and yields a maximum power conversion efficiency of 1.74% under AM 1.5 G illumination at an intensity of 100 mW/cm{sup 2}. It dramatically surpasses that (0.22%) of the ZnO/CuIn{sub 0.67}Ga{sub 0.33}Se{sub 2} planar thin-film device. Our work reveals that 1D nanoarray allows efficient photovoltaics without using toxic CdS buffer layer.

Space Photovoltaic Research and Technology 1995

Science.gov (United States)

Landis, Geoffrey (Compiler)

1995-01-01

The Fourteenth Space Photovoltaic Research and Technology conference was held at the NASA Lewis Research Center from October 24-26, 1995. The abstracts presented in this volume report substantial progress in a variety of areas in space photovoltaics. Technical and review papers were presented in many areas, including high efficiency GaAs and InP solar cells, GaAs/Ge cells as commercial items, high efficiency multiple bandgap cells, solar cell and array technology, heteroepitaxial cells, thermophotovoltaic energy conversion, and space radiation effects. Space flight data on a variety of cells were also presented.

Photovoltaic technologies for commerical power generation

International Nuclear Information System (INIS)

Carlson, D.E.

1990-01-01

The author reports photovoltaic power generation is an attractive source of energy since it involves the direct conversion of sunlight into electricity with no moving parts and no pollution. Following the demonstration of the first solar cell 35 years ago at Bell Laboratories, a steady stream of scientific and commercial progress has led to a rapid increase in applications in recent years. The first commercial application of solar cells occurred more than 20 years ago when they were used to supply power for space satellites, and even today photovoltaic arrays are used to supply electricity for most satellites and space probes. This paper reviews the status of the various photovoltaic technologies as well as present applications. The prospects for both distributed and central station grid-connected systems are discussed. The paper concludes with a discussion of the institutional and political factors that will affect the introduction of grid-connected photovoltaic power systems

Design and Implementation of a Simulator for Photovoltaic Modules

Directory of Open Access Journals (Sweden)

Kuang-Hui Tang

2012-01-01

Full Text Available Proposed in this paper is the development of a photovoltaic module simulator, one capable of running an output characteristic simulation under normal operation according to various electrical parameters specified and exhibiting multiple advantages of being low cost, small sized, and easy to implement. In comparison with commercial simulation tools, Pspice and Solar Pro, the simulator developed demonstrates a comparable I-V as well as a P-V output characteristic curve. In addition, a series-parallel configuration of individual modules constitutes a photovoltaic module array, which turns into a photovoltaic power generation system with an integrated power conditioner.

Design and Flood Control Assessment of 5MWp Fishing and Photovoltaic Power Project in Xinghua City

Science.gov (United States)

Guo, Liuchao; Hu, Xiaodong; Su, Yuyan; Wu, Peipei; Weng, Songgan

2017-12-01

In order to reduce coal consumption in Jiangsu Province and develop new energy sources, considering on the distribution of geology, solar energy resources, traffic and grid connection in Xinghua City, the aim is to determine the configuration of photovoltaic modules and photovoltaic array tracking mode, design photovoltaic array and layout scheme. But the project is a wading project, it is built in Dong Tan Lake polder I115, it needs scientific and reasonable evaluation to the effect of Dong Tan Lake’s flood storage and discharge. The results can provide guidance for similar engineering’s design.

Second update of the database of photovoltaic installations in the UK

Energy Technology Data Exchange (ETDEWEB)

Taylor, D; Bruhns, H

2001-07-01

This update of the database of photovoltaic (PV) installations in the UK developed by Altechnica for the Department of Trade and Industry has double the number of records of the previous edition, and focuses on the use of photovoltaic (PV) installations for buildings, for example using some form of a PV array, building integrated PV module, and building attached PV array. The growth in building related PV installations is examined along with the use of PV in telecommunication equipment, navigation buoys and light vessels, buildings, pumps for solar water heating systems, schools, lighthouses, and petrol stations. Details are given of the electronic data entry form for the database and the increase in the number of fields to allow additional information such as tilt angle and orientation area of the array to be added.

Photovoltaic sources modeling

CERN Document Server

Petrone, Giovanni; Spagnuolo, Giovanni

2016-01-01

This comprehensive guide surveys all available models for simulating a photovoltaic (PV) generator at different levels of granularity, from cell to system level, in uniform as well as in mismatched conditions. Providing a thorough comparison among the models, engineers have all the elements needed to choose the right PV array model for specific applications or environmental conditions matched with the model of the electronic circuit used to maximize the PV power production.

Fuzzy logic control of stand-alone photovoltaic system with battery storage

Science.gov (United States)

Lalouni, S.; Rekioua, D.; Rekioua, T.; Matagne, E.

Photovoltaic energy has nowadays an increased importance in electrical power applications, since it is considered as an essentially inexhaustible and broadly available energy resource. However, the output power provided via the photovoltaic conversion process depends on solar irradiation and temperature. Therefore, to maximize the efficiency of the photovoltaic energy system, it is necessary to track the maximum power point of the PV array. The present paper proposes a maximum power point tracker (MPPT) method, based on fuzzy logic controller (FLC), applied to a stand-alone photovoltaic system. It uses a sampling measure of the PV array power and voltage then determines an optimal increment required to have the optimal operating voltage which permits maximum power tracking. This method carries high accuracy around the optimum point when compared to the conventional one. The stand-alone photovoltaic system used in this paper includes two bi-directional DC/DC converters and a lead-acid battery bank to overcome the scare periods. One converter works as an MPP tracker, while the other regulates the batteries state of charge and compensates the power deficit to provide a continuous delivery of energy to the load. The Obtained simulation results show the effectiveness of the proposed fuzzy logic controller.

Implementation of the first student-designed PV array in Canada

International Nuclear Information System (INIS)

Hadlock, C.; DeLoyde, J.; Dhir, T.

2004-01-01

This paper is a culmination of a 2-year project involving students, faculty, staff member, and private industry. Solar Technology Education Project (STEP) became the first student-led group to successfully install a 36-panel photovoltaic (PV) array on a Canadian University campus. The fundraising, design, and assembly of the PV array was entirely student driven. The project was completed in January 2004 with the installation of a 2 kW photovoltaic grid-tied array mounted to the roof of the University of Waterloo's Federation Hall, the largest student-run pub in North America. The photovoltaic array was a demonstration project to raise awareness about solar technology and the need for energy efficiency in buildings. It took two years to complete the project, which was implemented in three phases. The first phase was aimed at raising the required capital. The second phase included design and fabrication of the array. The third phase, still ongoing today, is the community outreach phase, which involves educating the surrounding communities about the project, solar technology, and the role of individuals in combating global warming. This paper examines the steps required for the implementation of a successful educational photovoltaic project, using the students' experience as a roadmap. A section highlighting what's next for STEP is also presented as the students attempt to build on the momentum from the project. The aim is to launch a solar thermal project on another University of Waterloo building to move one step closer to the ultimate goal of a sustainable campus

Intelligent fault diagnosis of photovoltaic arrays based on optimized kernel extreme learning machine and I-V characteristics

International Nuclear Information System (INIS)

Chen, Zhicong; Wu, Lijun; Cheng, Shuying; Lin, Peijie; Wu, Yue; Lin, Wencheng

2017-01-01

Highlights: •An improved Simulink based modeling method is proposed for PV modules and arrays. •Key points of I-V curves and PV model parameters are used as the feature variables. •Kernel extreme learning machine (KELM) is explored for PV arrays fault diagnosis. •The parameters of KELM algorithm are optimized by the Nelder-Mead simplex method. •The optimized KELM fault diagnosis model achieves high accuracy and reliability. -- Abstract: Fault diagnosis of photovoltaic (PV) arrays is important for improving the reliability, efficiency and safety of PV power stations, because the PV arrays usually operate in harsh outdoor environment and tend to suffer various faults. Due to the nonlinear output characteristics and varying operating environment of PV arrays, many machine learning based fault diagnosis methods have been proposed. However, there still exist some issues: fault diagnosis performance is still limited due to insufficient monitored information; fault diagnosis models are not efficient to be trained and updated; labeled fault data samples are hard to obtain by field experiments. To address these issues, this paper makes contribution in the following three aspects: (1) based on the key points and model parameters extracted from monitored I-V characteristic curves and environment condition, an effective and efficient feature vector of seven dimensions is proposed as the input of the fault diagnosis model; (2) the emerging kernel based extreme learning machine (KELM), which features extremely fast learning speed and good generalization performance, is utilized to automatically establish the fault diagnosis model. Moreover, the Nelder-Mead Simplex (NMS) optimization method is employed to optimize the KELM parameters which affect the classification performance; (3) an improved accurate Simulink based PV modeling approach is proposed for a laboratory PV array to facilitate the fault simulation and data sample acquisition. Intensive fault experiments are

600 Volt Stretched Lens Array for Solar Electric Propulsion, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — ENTECH, Auburn, NASA, and others have recently developed a new space photovoltaic array called the Stretched Lens Array (SLA), offering unprecedented performance...

Development of a microprocessor controller for stand-alone photovoltaic power systems

Science.gov (United States)

Millner, A. R.; Kaufman, D. L.

1984-01-01

A controller for stand-alone photovoltaic systems has been developed using a low power CMOS microprocessor. It performs battery state of charge estimation, array control, load management, instrumentation, automatic testing, and communications functions. Array control options are sequential subarray switching and maximum power control. A calculator keypad and LCD display provides manual control, fault diagnosis and digital multimeter functions. An RS-232 port provides data logging or remote control capability. A prototype 5 kW unit has been built and tested successfully. The controller is expected to be useful in village photovoltaic power systems, large solar water pumping installations, and other battery management applications.

Preliminary Demonstration of Power Beaming With Non-Coherent Laser Diode Arrays

National Research Council Canada - National Science Library

Kare, Jordin

1999-01-01

A preliminary demonstration of free-space electric power transmission has been conducted using non-coherent laser diode arrays as the transmitter and standard silicon photovoltaic cell arrays as the receiver...

Interference Lithography for Vertical Photovoltaics

Science.gov (United States)

Balls, Amy; Pei, Lei; Kvavle, Joshua; Sieler, Andrew; Schultz, Stephen; Linford, Matthew; Vanfleet, Richard; Davis, Robert

2009-10-01

We are exploring low cost approaches for fabricating three dimensional nanoscale structures. These vertical structures could significantly improve the efficiency of devices made from low cost photovoltaic materials. The nanoscale vertical structure provides a way to increase optical absorption in thin photovoltaic films without increasing the electronic carrier separation distance. The target structure is a high temperature transparent template with a dense array of holes on a 400 - 600 nm pitch fabricated by a combination of interference lithography and nanoembossing. First a master was fabricated using ultraviolet light interference lithography and the pattern was transferred into a silicon wafer master by silicon reactive ion etching. Embossing studies were performed with the master on several high temperature polymers.

Photovoltaics at Point Pelee Park

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-12-01

Case study of an Ontario Hydro-installed photovoltaic system at Point Pelee Park, a bird sanctuary located on Lake Erie, is described. The system consists of a 1080 W photovoltaic array used to supply electricity to one of the washrooms. The cost for installing the system was $30,000 which was considerably cheaper than the $100,000 estimate for an underground power line. The independent system is the only source of energy for the washroom, therefore it was necessary to reduce the total electrical demand required by the facility. Electricity was used for the water pump, chlorinator and lighting. Motion sensors were installed to further reduce electrical demand. Washroom heaters were converted to propane. 2 figs.

Method of manufacturing a large-area segmented photovoltaic module

Science.gov (United States)

Lenox, Carl

2013-11-05

One embodiment of the invention relates to a segmented photovoltaic (PV) module which is manufactured from laminate segments. The segmented PV module includes rectangular-shaped laminate segments formed from rectangular-shaped PV laminates and further includes non-rectangular-shaped laminate segments formed from rectangular-shaped and approximately-triangular-shaped PV laminates. The laminate segments are mechanically joined and electrically interconnected to form the segmented module. Another embodiment relates to a method of manufacturing a large-area segmented photovoltaic module from laminate segments of various shapes. Other embodiments relate to processes for providing a photovoltaic array for installation at a site. Other embodiments and features are also disclosed.

Preprint server seeks way to halt plagiarists

CERN Multimedia

Giles, J

2003-01-01

"An unusual case of plagiarism has struck ArXiv, the popular physics preprint server at Cornell University in Ithaca, New York, resulting in the withdrawal of 22 papers...The plagiarism case traces its origins to June 2002, when Yasushi Watanabe, a high-energy physicist at the Tokyo Insitute of Technology, was contacted by Ramy Noboulsi, who said he was a mathematical physicist" (1 page)

600 Volt Stretched Lens Array for Solar Electric Propulsion, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Over the past six years, ENTECH, Auburn, NASA, and other organizations have developed a new space photovoltaic array called the Stretched Lens Array (SLA), which...

Update of the database of photovoltaic installations in the UK

Energy Technology Data Exchange (ETDEWEB)

Taylor, D.; Bruhns, H.

1999-07-01

The article describes an updated database of photovoltaic (PV) installations in the UK. The database contains more than 300 records representing over 40,000 photovoltaic installations with more than 100 buildings that use photovoltaic arrays. Figures show: (i) a chart of cumulative PV applications to date; (ii) a chart of cumulative installations in the database; (iii) the growth of Building Integrated PV installed to date; (iv) the cumulative growth of peak power of PV for buildings installed every year since 1985; (v) the distribution by application of all PV installations in the database and (vi) the various applications of PV installations.

A Weakest-Link Approach for Fatigue Limit of 30CrNiMo8 Steels (Preprint)

Science.gov (United States)

2011-03-01

34Application of a Weakest-Link Concept to the Fatigue Limit of the Bearing Steel Sae 52100 in a Bainitic Condition," Fatigue and Fracture of...AFRL-RX-WP-TP-2011-4206 A WEAKEST-LINK APPROACH FOR FATIGUE LIMIT OF 30CrNiMo8 STEELS (PREPRINT) S. Ekwaro-Osire and H.V. Kulkarni Texas...2011 4. TITLE AND SUBTITLE A WEAKEST-LINK APPROACH FOR FATIGUE LIMIT OF 30CrNiMo8 STEELS (PREPRINT) 5a. CONTRACT NUMBER In-house 5b. GRANT

Space and industrial markets for photovoltaics

Energy Technology Data Exchange (ETDEWEB)

Huggins, C.R.; Hardingham, C.M.

2000-07-01

This report presents a review of applications, technologies and markets for photovoltaic power (PV) supplies. A brief history of PV and PV principles is presented, and an overview of the satellite industry is given. Space arrays, space PV, terrestrial PV, and thermo photovoltaics are examined. Targets and constraints in space and terrestrial solar cells are compared, and details of commercial market sizes for given technologies in space and terrestrial PV in 1999, and technical barriers to be overcome towards development of existing products are tabulated. The scope for cross-culture interaction in all aspects of manufacturing, testing and evaluation in the PV devices are considered. (UK)

Space and industrial markets for photovoltaics

International Nuclear Information System (INIS)

Huggins, C.R.; Hardingham, C.M.

2000-01-01

This report presents a review of applications, technologies and markets for photovoltaic power (PV) supplies. A brief history of PV and PV principles is presented, and an overview of the satellite industry is given. Space arrays, space PV, terrestrial PV, and thermo photovoltaics are examined. Targets and constraints in space and terrestrial solar cells are compared, and details of commercial market sizes for given technologies in space and terrestrial PV in 1999, and technical barriers to be overcome towards development of existing products are tabulated. The scope for cross-culture interaction in all aspects of manufacturing, testing and evaluation in the PV devices are considered. (UK)

A Method of Maximum Power Control in Single-phase Utility Interactive Photovoltaic Generation System by using PWM Current Source Inverter

Science.gov (United States)

Neba, Yasuhiko

This paper deals with a maximum power point tracking (MPPT) control of the photovoltaic generation with the single-phase utility interactive inverter. The photovoltaic arrays are connected by employing the PWM current source inverter to the utility. The use of the pulsating dc current and voltage allows the maximum power point to be searched. The inverter can regulate the array voltage and keep the arrays to the maximum power. This paper gives the control method and the experimental results.

Fire-induced reradiation underneath photovoltaic arrays on flat roofs

DEFF Research Database (Denmark)

Kristensen, Jens Steemann; Merci, Bart; Jomaas, Grunde

2018-01-01

The impact of the reflection of fire-induced heat from a gas burner was studied experimentally to gain knowledge on the interaction between photovoltaic (PV) panels and a fire on flat roofs. The heat flux was measured in a total of eight points at the same level as the top of the gas burner. The ...

Optimal design of aperiodic, vertical silicon nanowire structures for photovoltaics.

Science.gov (United States)

Lin, Chenxi; Povinelli, Michelle L

2011-09-12

We design a partially aperiodic, vertically-aligned silicon nanowire array that maximizes photovoltaic absorption. The optimal structure is obtained using a random walk algorithm with transfer matrix method based electromagnetic forward solver. The optimal, aperiodic structure exhibits a 2.35 times enhancement in ultimate efficiency compared to its periodic counterpart. The spectral behavior mimics that of a periodic array with larger lattice constant. For our system, we find that randomly-selected, aperiodic structures invariably outperform the periodic array.

Photovoltaic power converter system with a controller configured to actively compensate load harmonics

Science.gov (United States)

de Rooij, Michael Andrew; Steigerwald, Robert Louis; Delgado, Eladio Clemente

2008-12-16

Photovoltaic power converter system including a controller configured to reduce load harmonics is provided. The system comprises a photovoltaic array and an inverter electrically coupled to the array to generate an output current for energizing a load connected to the inverter and to a mains grid supply voltage. The system further comprises a controller including a first circuit coupled to receive a load current to measure a harmonic current in the load current. The controller includes a second circuit to generate a fundamental reference drawn by the load. The controller further includes a third circuit for combining the measured harmonic current and the fundamental reference to generate a command output signal for generating the output current for energizing the load connected to the inverter. The photovoltaic system may be configured to compensate harmonic currents that may be drawn by the load.

Prediction of power fluctuation classes for photovoltaic installations and potential benefits of dynamic reserve allocation

NARCIS (Netherlands)

Nijhuis, M.; Rawn, B.G.; Gibescu, M.

2014-01-01

During partly cloudy conditions, the power delivered by a photovoltaic array can easily fluctuate by three quarters of its rated power in 10 s. Fluctuations from photovoltaics of this size and on this time scale may necessitate adding an additional component to power system secondary and primary

The influence of passivation and photovoltaic properties of α-Si:H coverage on silicon nanowire array solar cells

Science.gov (United States)

2013-01-01

Silicon nanowire (SiNW) arrays for radial p-n junction solar cells offer potential advantages of light trapping effects and quick charge collection. Nevertheless, lower open circuit voltages (Voc) lead to lower energy conversion efficiencies. In such cases, the performance of the solar cells depends critically on the quality of the SiNW interfaces. In this study, SiNW core-shell solar cells have been fabricated by growing crystalline silicon (c-Si) nanowires via the metal-assisted chemical etching method and by depositing hydrogenated amorphous silicon (α-Si:H) via the plasma-enhanced chemical vapor deposition (PECVD) method. The influence of deposition parameters on the coverage and, consequently, the passivation and photovoltaic properties of α-Si:H layers on SiNW solar cells have been analyzed. PMID:24059343

Design of Arrangement of Solar Array and Energy Storage in Solar Photovoltaic Generation%光伏阵列及储能的布置设计

Institute of Scientific and Technical Information of China (English)

韩学栋; 王海华

2015-01-01

Facing energy and environmental pressure, solar which is a kind natural renewable clean energy has become the focus of world development and utilization. This paper describes the optimal choice of the best dip angle of the solar array, deducing the layout spacing theoretical formula when the battery array in the horizontal plane and on the roof with a slope. Also, the paper describes the formula of the calculating components in series and parallel arrays of photovoltaic cells and storage cells in series and parallel. This paper provides some theoretical support to the design of the photovoltaic power generation system.%在能源和环境的双重压力下，太阳能这一清洁可再生的自然能源成为世界各国开发利用的重点。本文介绍了太阳能电池阵列最佳倾角的优化选择，推导了电池阵列在水平面以及带有一定坡度的屋面上进行布置时前后间距的理论计算公式，介绍了光伏电池阵列中组件的串并联以及储能蓄电池的串并联计算公式。上述工作对太阳能光伏发电系统的设计提供了一定的理论支撑。

Photovoltaics: systems considerations

Energy Technology Data Exchange (ETDEWEB)

Haq, A M

1982-08-01

Photovoltaics applications to date and the potential uses and growth of this alternative energy source for the future are examined in the light of present world economic conditions. In addition, a more detailed description is given, illustrating the method by which system sizing and design are calculated and mentioning such factors as local solar radiation and insolation levels, humidity, wind loading and altitude, all of which affect the optimal system size. The role of computer programming in these calculations is also outlined, illustrating the way in which deterioration, battery losses, poor weather etc. can be accounted and compensated for in the systems design process. The elements of the actual systems are also described, including details of the solar cells and arrays, the electronic controls incorporated in the systems and the characteristics of the batteries used. A resume of projected costs and current technological advances in silicon processing techniques is given together with an analysis of present and future growth trends in the photovoltaics industry.

Calibration and Measurement Uncertainty Estimation of Radiometric Data: Preprint

Energy Technology Data Exchange (ETDEWEB)

Habte, A.; Sengupta, M.; Reda, I.; Andreas, A.; Konings, J.

2014-11-01

Evaluating the performance of photovoltaic cells, modules, and arrays that form large solar deployments relies on accurate measurements of the available solar resource. Therefore, determining the accuracy of these solar radiation measurements provides a better understanding of investment risks. This paper provides guidelines and recommended procedures for estimating the uncertainty in calibrations and measurements by radiometers using methods that follow the International Bureau of Weights and Measures Guide to the Expression of Uncertainty (GUM). Standardized analysis based on these procedures ensures that the uncertainty quoted is well documented.

Inorganic Photovoltaics Materials and Devices: Past, Present, and Future

Science.gov (United States)

Hepp, Aloysius F.; Bailey, Sheila G.; Rafaelle, Ryne P.

2005-01-01

This report describes recent aspects of advanced inorganic materials for photovoltaics or solar cell applications. Specific materials examined will be high-efficiency silicon, gallium arsenide and related materials, and thin-film materials, particularly amorphous silicon and (polycrystalline) copper indium selenide. Some of the advanced concepts discussed include multi-junction III-V (and thin-film) devices, utilization of nanotechnology, specifically quantum dots, low-temperature chemical processing, polymer substrates for lightweight and low-cost solar arrays, concentrator cells, and integrated power devices. While many of these technologies will eventually be used for utility and consumer applications, their genesis can be traced back to challenging problems related to power generation for aerospace and defense. Because this overview of inorganic materials is included in a monogram focused on organic photovoltaics, fundamental issues and metrics common to all solar cell devices (and arrays) will be addressed.

Potential high efficiency solar cells: Applications from space photovoltaic research

Science.gov (United States)

Flood, D. J.

1986-01-01

NASA involvement in photovoltaic energy conversion research development and applications spans over two decades of continuous progress. Solar cell research and development programs conducted by the Lewis Research Center's Photovoltaic Branch have produced a sound technology base not only for the space program, but for terrestrial applications as well. The fundamental goals which have guided the NASA photovoltaic program are to improve the efficiency and lifetime, and to reduce the mass and cost of photovoltaic energy conversion devices and arrays for use in space. The major efforts in the current Lewis program are on high efficiency, single crystal GaAs planar and concentrator cells, radiation hard InP cells, and superlattice solar cells. A brief historical perspective of accomplishments in high efficiency space solar cells will be given, and current work in all of the above categories will be described. The applicability of space cell research and technology to terrestrial photovoltaics will be discussed.

Effect of wind speed on performance of a solar-pv array

Science.gov (United States)

Thousands of solar photovoltaic (PV) arrays have been installed over the past few years, but the effect of wind speed on the predicted performance of PV arrays is not usually considered by installers. An increase in wind speed will cool the PV array, and the electrical power of the PV modules will ...

Photovoltaic module mounting system

Science.gov (United States)

Miros, Robert H. J. [Fairfax, CA; Mittan, Margaret Birmingham [Oakland, CA; Seery, Martin N [San Rafael, CA; Holland, Rodney H [Novato, CA

2012-04-17

A solar array mounting system having unique installation, load distribution, and grounding features, and which is adaptable for mounting solar panels having no external frame. The solar array mounting system includes flexible, pedestal-style feet and structural links connected in a grid formation on the mounting surface. The photovoltaic modules are secured in place via the use of attachment clamps that grip the edge of the typically glass substrate. The panel mounting clamps are then held in place by tilt brackets and/or mid-link brackets that provide fixation for the clamps and align the solar panels at a tilt to the horizontal mounting surface. The tilt brackets are held in place atop the flexible feet and connected link members thus creating a complete mounting structure.

Photovoltaic Pixels for Neural Stimulation: Circuit Models and Performance.

Science.gov (United States)

Boinagrov, David; Lei, Xin; Goetz, Georges; Kamins, Theodore I; Mathieson, Keith; Galambos, Ludwig; Harris, James S; Palanker, Daniel

2016-02-01

Photovoltaic conversion of pulsed light into pulsed electric current enables optically-activated neural stimulation with miniature wireless implants. In photovoltaic retinal prostheses, patterns of near-infrared light projected from video goggles onto subretinal arrays of photovoltaic pixels are converted into patterns of current to stimulate the inner retinal neurons. We describe a model of these devices and evaluate the performance of photovoltaic circuits, including the electrode-electrolyte interface. Characteristics of the electrodes measured in saline with various voltages, pulse durations, and polarities were modeled as voltage-dependent capacitances and Faradaic resistances. The resulting mathematical model of the circuit yielded dynamics of the electric current generated by the photovoltaic pixels illuminated by pulsed light. Voltages measured in saline with a pipette electrode above the pixel closely matched results of the model. Using the circuit model, our pixel design was optimized for maximum charge injection under various lighting conditions and for different stimulation thresholds. To speed discharge of the electrodes between the pulses of light, a shunt resistor was introduced and optimized for high frequency stimulation.

Microprocessor-controlled step-down maximum-power-point tracker for photovoltaic systems

Science.gov (United States)

Mazmuder, R. K.; Haidar, S.

1992-12-01

An efficient maximum power point tracker (MPPT) has been developed and can be used with a photovoltaic (PV) array and a load which requires lower voltage than the PV array voltage to be operated. The MPPT makes the PV array to operate at maximum power point (MPP) under all insolation and temperature, which ensures the maximum amount of available PV power to be delivered to the load. The performance of the MPPT has been studied under different insolation levels.

Partial Shade Evaluation of Distributed Power Electronics for Photovoltaic Systems: Preprint

Energy Technology Data Exchange (ETDEWEB)

Deline, C.; Meydbrav, J.; Donovan, M.

2012-06-01

Site survey data for several residential installations are provided, showing the extent and frequency of shade throughout the year. This background information is used to design a representative shading test that is conducted on two side-by-side 8-kW photovoltaic (PV) installations. One system is equipped with a standard string inverter, while the other is equipped with microinverters on each solar panel. Partial shade is applied to both systems in a comprehensive range of shading conditions, simulating one of three shade extents. Under light shading conditions, the microinverter system produced the equivalent of 4% annual performance improvement, relative to the string inverter system. Under moderate shading conditions, the microinverter system outperformed the string inverter system by 8%, and under heavy shading the microinverter increased relative performance by 12%. In all three cases, the percentage of performance loss that is recovered by the use of distributed power electronics is 40%-50%. Additionally, it was found that certain shading conditions can lead to additional losses in string inverters due to peak-power tracking errors and voltage limitations.

Microcomputer control of a residential photovoltaic power conditioning system

Energy Technology Data Exchange (ETDEWEB)

Bose, B.K.; Steigerwald, R.L.; Szczesny, P.M.

1984-01-01

Microcomputer-based control of a residential photovoltaic power conditioning system is described. The microcomputer is responsible for array current feedback control, maximum power tracking control, array safe zone steering control, phase-locked reference wave synthesis, sequencing control, and some diagnostics. The control functions are implemented using Intel 8751 single-chip microcomputer-based hardware and software. The controller has been tested in the laboratory with the prototype power conditioner and shows excellent performance.

Microcomputer control of a residential photovoltaic power conditioning system

Energy Technology Data Exchange (ETDEWEB)

Bose, B.K.; Steigerwald, R.L.; Szczesny, P.M.

1985-09-01

Microcomputer-based control of a residential photovoltaic power conditioning system is described. The microcomputer is responsible for array current feedback control, maximum power tracking control, array safe zone steering control, phase-locked reference wave synthesis, sequencing control, and some diagnostics. The control functions are implemented using Intel 8751 single-chip microcomputer-based hardware and software. The controller has been tested in the laboratory with the prototype power conditioner and shows excellent performance.

A New Approach for Optimal Sizing of Standalone Photovoltaic Systems

OpenAIRE

Khatib, Tamer; Mohamed, Azah; Sopian, K.; Mahmoud, M.

2012-01-01

This paper presents a new method for determining the optimal sizing of standalone photovoltaic (PV) system in terms of optimal sizing of PV array and battery storage. A standalone PV system energy flow is first analysed, and the MATLAB fitting tool is used to fit the resultant sizing curves in order to derive general formulas for optimal sizing of PV array and battery. In deriving the formulas for optimal sizing of PV array and battery, the data considered are based on five sites in Malaysia...

Performance characteristics of solar-photovoltaic flywheel-storage systems

Science.gov (United States)

Jarvinen, P. O.; Brench, B. L.; Rasmussen, N. E.

A solar photovoltaic energy flywheel storage and conversion system for residential applications was tested. Performance and efficiency measurements were conducted on the system, which utilizes low loss magnetic bearings, maximum power point tracking of the photovoltaic array, integrated permanent magnet motor generator, and output power conditioning sections of either the stand alone cycloconverter or utility interactive inverter type. The overall in/out electrical storage efficiency of the flywheel system was measured along with the power transfer efficiencies of the individual components and the system spin down tare losses. The system compares favorably with systems which use batteries and inverters.

Solar photovoltaic water pumping system using a new linear actuator

OpenAIRE

Andrada Gascón, Pedro; Castro, Javier

2007-01-01

In this paper a photovoltaic solar pumping system using a new linear actuator is presented. This linear actuator is a double-sided flat two-phase variable-reluctance linear stepper motor that moves a piston-type water pump with the help of a rope, a pulley and a counterweight. The entire actuator pump ensemble is controlled by a simple electronic unit that manages the electric power generated by a photovoltaic array. The proposed system is suitable for rural communities in developing...

Modeling and Implementing a Digitally Embedded Maximum Power Point Tracking Algorithm and a Series-Loaded Resonant DC-DC Converter to Integrate a Photovoltaic Array with a Micro-Grid

Science.gov (United States)

2014-09-01

These renewable energy sources can include solar, wind, geothermal , biomass, hydroelectric, and nuclear. Of these sources, photovoltaic (PV) arrays...renewable energy source [1]. These renewable energy sources can include solar, wind, geothermal , biomass, hydroelectric, and nuclear. Of these sources...26, May 2011. [6] H. G. Xu, J. P. He, Y. Qin, and Y. H. Li, “Energy management and control strategy for DC micro-grid in data center,” China

Performance enhancement of photovoltaic array through string and central based MPPT system under non-uniform irradiance conditions

International Nuclear Information System (INIS)

Syafaruddin; Karatepe, Engin; Hiyama, Takashi

2012-01-01

Highlights: ► We propose MPPT method for tracking global MPP of PV arrays under non-uniform irradiance conditions. ► We compare the performance of string and central based MPPT. ► Intelligent control method is utilized to identify the global operating voltage in string and central based MPPT system. ► The performance of proposed method is tested on different size of PV. - Abstract: Mismatching losses reduction of photovoltaic (PV) array has been intensively discussed through the increasing penetration of residential and commercial PV systems. Many causes of mismatching losses have been identified and plenty of proposed methods to solve this problem have been recently proposed. This paper deals with reducing method of mismatching losses due to the non-uniform irradiance conditions. It is well-known that a certain number of multiple peaks occur on the power–voltage curve as the number of PV modules in one-string increases under non-uniform operating conditions. Since the conventional control method only drives the operating points of PV system to the local maxima close to open circuit voltage, only small portion of power can be extracted from the PV system. In this study, a radial basis function neural network (RBF-ANN) based intelligent control method is utilized to map the global operating voltage and non-irradiance operating condition in string and central based MPPT systems. The proposed method has been tested on 10 × 3 (2.2 kW), 15 × 3 (2.5 kW) and 20 × 3 (3.3 kW) of series–parallel PV array configuration under random-shaded and continuous-shaded patterns. The proposed method is compared with the ideal case and conventional method through a simple power–voltage curve of PV arrays. The simulation results show that there are significant increases of about 30–60% of the extracted power in one operating condition when the proposed method is able to shift the operating voltage of modules to their optimum voltages.

Daytime Solar Heating of Photovoltaic Arrays in Low Density Plasmas

Science.gov (United States)

Galofaro, J.; Vayner, B.; Ferguson, D.

2003-01-01

The purpose of the current work is to determine the out-gassing rate of H2O molecules for a solar array placed under daytime solar heating (full sunlight) conditions typically encountered in a Low Earth Orbital (LEO) environment. Arc rates are established for individual arrays held at 14 C and are used as a baseline for future comparisons. Radiated thermal solar flux incident to the array is simulated by mounting a stainless steel panel equipped with resistive heating elements several centimeters behind the array. A thermal plot of the heater plate temperature and the array temperature as a function of heating time is then obtained. A mass spectrometer is used to record the levels of partial pressure of water vapor in the test chamber after each of the 5 heating/cooling cycles. Each of the heating cycles was set to time duration of 40 minutes to simulate the daytime solar heat flux to the array over a single orbit. Finally the array is cooled back to ambient temperature after 5 complete cycles and the arc rates of the solar arrays is retested. A comparison of the various data is presented with rather some unexpected results.

Intermediate photovoltaic system application experiment operational performance. Executive summary. Volume 6 for Beverly High School, Beverly, MA

Energy Technology Data Exchange (ETDEWEB)

None

1982-04-01

Performance data are given for a 95 kW-peak grid connected flat panel photovoltaic power supply at a Massachusetts high school for the month of March 1982. Data presented include daily and monthly electrical energy produced by the photovoltaic system, daily and monthly solar energy incident in the plane of the array, efficiency of the solar cell array and of the power conditioner and of the system overall, the capacity factor, solar insolation, and the data acquisition mode and recording interval plot. (LEW)

Computer Drawing Method for Operating Characteristic Curve of PV Power Plant Array Unit

Science.gov (United States)

Tan, Jianbin

2018-02-01

According to the engineering design of large-scale grid-connected photovoltaic power stations and the research and development of many simulation and analysis systems, it is necessary to draw a good computer graphics of the operating characteristic curves of photovoltaic array elements and to propose a good segmentation non-linear interpolation algorithm. In the calculation method, Component performance parameters as the main design basis, the computer can get 5 PV module performances. At the same time, combined with the PV array series and parallel connection, the computer drawing of the performance curve of the PV array unit can be realized. At the same time, the specific data onto the module of PV development software can be calculated, and the good operation of PV array unit can be improved on practical application.

Passive P-control of a grid-connected photovoltaic inverter

NARCIS (Netherlands)

Meza, C.; Jeltsema, D.; Scherpen, J. M. A.; Biel, D.

2008-01-01

A passive P-controller for a single-phase single-stage grid-connected photovoltaic inverter is presented. Explicit dependance of the PV array parameters on external unpredictable variables such as temperature and solar irradiance is avoided by extending the control scheme with a reference estimator.

Nonimaging solar concentrator with near-uniform irradiance for photovoltaic arrays

Science.gov (United States)

O'Gallagher, Joseph J.; Winston, Roland; Gee, Randy

2001-11-01

We report results of a study our group has undertaken to design a solar concentrator with uniform irradiance on a planar target. This attribute is especially important for photovoltaic concentrators. We find that a variety of optical mixers, some incorporating a moderate level of concentration, can be quite effective in achieving near uniform irradiance.

Optimal Design of MPPT Controllers for Grid Connected Photovoltaic Array System

Science.gov (United States)

Ebrahim, M. A.; AbdelHadi, H. A.; Mahmoud, H. M.; Saied, E. M.; Salama, M. M.

2016-10-01

Integrating photovoltaic (PV) plants into electric power system exhibits challenges to power system dynamic performance. These challenges stem primarily from the natural characteristics of PV plants, which differ in some respects from the conventional plants. The most significant challenge is how to extract and regulate the maximum power from the sun. This paper presents the optimal design for the most commonly used Maximum Power Point Tracking (MPPT) techniques based on Proportional Integral tuned by Particle Swarm Optimization (PI-PSO). These suggested techniques are, (1) the incremental conductance, (2) perturb and observe, (3) fractional short circuit current and (4) fractional open circuit voltage techniques. This research work provides a comprehensive comparative study with the energy availability ratio from photovoltaic panels. The simulation results proved that the proposed controllers have an impressive tracking response. The system dynamic performance improved greatly using the proposed controllers.

Development, analysis and assessment of a fuel cell and solar photovoltaic system powered vehicle

International Nuclear Information System (INIS)

Ezzat, M.F.; Dincer, I.

2016-01-01

Highlights: • A new integrated fuel cell-photovoltaic system for vehicle application is proposed. • Comprehensive energy and exergy analyses are conducted. • Detailed parametric study is performed. • Overall energy and exergy efficiencies are determined. • Photovoltaic utilization can save 561 g of hydrogen during 3 h drive. - Abstract: This paper deals with a new hybridly powered photovoltaic-fuel cell - Li-ion battery integrated system and is compared to a base system, consisting of PEM fuel cell and Li-ion battery. It investigates the effects of adding photovoltaic arrays to the base system and further effects on the overall energy and exergy efficiencies and hence hydrogen consumption. These two systems are analyzed and assessed both energetically and exergetically. The study results show that the overall energy and exergy efficiencies become 39.46% and 56.3%, respectively at a current density of 1150 mA/cm"2 for system 1 (fuel cell-battery). Moreover, energy and exergy efficiencies are found to be 39.86% and 56.63% at current density of 1150 mA/cm"2 for system 2 (fuel cell-battery-photovoltaics). Utilizing photovoltaic arrays in system 2 would recover 561 g of hydrogen through 3 h of continuous driving at max power of 98.32 kW, which is approximately 11.2% of the hydrogen storage tank used in the proposed systems. The effects of changing various system parameters on energy and exergy efficiencies of the overall system are also examined.

Energy requirement for the production of silicon solar arrays

Science.gov (United States)

Lindmayer, J.; Wihl, M.; Scheinine, A.; Rosenfield, T.; Wrigley, C. Y.; Morrison, A.; Anderson, J.; Clifford, A.; Lafky, W.

1977-01-01

The results of a study to investigate the feasibility of manufacturing photovoltaic solar array modules by the use of energy obtained from similar or identical photovoltaic sources are presented. The primary objective of this investigation was the characterization of the energy requirements of current and developing technologies which comprise the photovoltaic field. For cross-checking the energies of prevailing technologies data were also used and the wide-range assessment of alternative technologies included different refinement methods, various ways of producing light sheets, semicrystalline cells, etc. Energy data are utilized to model the behavior of a future solar breeder plant under various operational conditions.

Economical photovoltaic power generation with heat recovery

Science.gov (United States)

Ascher, G.

1977-01-01

Three designs for conversion of solar radiation to electricity and thermal energy are analyzed. The objective of these converters is to increase the electric and thermal output for each photovoltaic array so as to lower the cell cost relative to the amount of energy delivered. An analysis of the economical aspects of conversion by photovoltaic cells with heat recovery is carried out in terms of hypothetical examples. Thus, it is shown that the original cost of say $40,000 per generated kilowat can be reduced to $572.00 per kilowatt by increasing the original electric output of 1 kW to 10 kW in electricity and 60 kW in thermal energy. The newly derived specific cost is only 1.4 percent of the original one. It is expected that a cost reduction of roughly 2% of the present specific cost per kilowatt will greatly stimulate public acceptance of photovoltaic terrestrial conversion to electricity.

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

Science.gov (United States)

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

2012-01-01

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

Particle swarm optimization based solar PV array reconfiguration of the maximum power extraction under partial shading conditions

DEFF Research Database (Denmark)

Babu, Thanikanti Sudhakar; Ram, J. Prasanth; Dragicevic, Tomislav

2018-01-01

For large photovoltaic power generation plants, number of panels are interconnected in series and parallel to form a photovoltaic (PV) array. In this configuration, partial shade will result in decrease in power output and introduce multiple peaks in the P–V curve. As a consequence, the modules...... in the array will deliver different row currents. Therefore, to maximize the power extraction from PV array, the panels need to be reconfigured for row current difference minimization. Row current minimization via Su Do Ku game theory do physical relocation of panels may cause laborious work and lengthy...

Crossed BiOI flake array solar cells

Energy Technology Data Exchange (ETDEWEB)

Wang, Kewei; Jia, Falong; Zhang, Lizhi [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan (China); Zheng, Zhi [Institute of Surface Micro and Nano Materials, Xuchang University (China)

2010-12-15

We report a new kind of solar cell based on crossed flake-like BiOI arrays for the first time. The BiOI flake arrays were fabricated on an FTO glass with a TiO{sub 2} block layer at room temperature by successive ionic layer adsorption and reaction (SILAR) method. The resulting BiOI flake array solar cell exhibited enhanced photovoltaic performance under solar illumination. This work provides an attractive and new solar cell system and a facile route to fabricate low cost and non-toxic solar cell. (author)

Design description of the Tangaye Village photovoltaic power system

Science.gov (United States)

Martz, J. E.; Ratajczak, A. F.

1982-01-01

The engineering design of a stand alone photovoltaic (PV) powered grain mill and water pump for the village of Tangaye, Upper Volta is described. The socioeconomic effects of reducing the time required by women in rural areas for drawing water and grinding grain were studied. The suitability of photovoltaic technology for use in rural areas by people of limited technical training was demonstrated. The PV system consists of a 1.8-kW (peak) solar cell array, 540 ampere hours of battery storage, instrumentation, automatic controls, and a data collection and storage system. The PV system is situated near an improved village well and supplies d.c. power to a grain mill and a water pump. The array is located in a fenced area and the mill, battery, instruments, controls, and data system are in a mill building. A water storage tank is located near the well. The system employs automatic controls which provide battery charge regulation and system over and under voltage protection. This report includes descriptions of the engineering design of the system and of the load that it serves; a discussion of PV array and battery sizing methodology; descriptions of the mechanical and electrical designs including the array, battery, controls, and instrumentation; and a discussion of the safety features. The system became operational on March 1, 1979.

Photovoltaic applications of Compound Parabolic Concentrator (CPC)

Science.gov (United States)

Winston, R.

1975-01-01

The use of a compound parabolic concentrator as field collector, in conjunction with a primary focusing concentrator for photovoltaic applications is studied. The primary focusing concentrator can be a parabolic reflector, an array of Fresnel mirrors, a Fresnel lens or some other lens. Silicon solar cell grid structures are proposed that increase efficiency with concentration up to 10 suns. A ray tracing program has been developed to determine energy distribution at the exit of a compound parabolic concentrator. Projected total cost of a CPC/solar cell system will be between 4 and 5 times lower than for flat plate silicon cell arrays.

Analysis of the economics of photovoltaic-diesel-battery energy systems for remote applications

Science.gov (United States)

Brainard, W. A.

1983-01-01

Computer simulations were conducted to analyze the performance and operating cost of a photovoltaic energy source combined with a diesel generator system and battery storage. The simulations were based on the load demand profiles used for the design of an all photovoltaic energy system installed in the remote Papago Indian Village of Schuchuli, Arizona. Twenty year simulations were run using solar insolation data from Phoenix SOLMET tapes. Total energy produced, energy consumed, operation and maintenance costs were calculated. The life cycle and levelized energy costs were determined for a variety of system configurations (i.e., varying amounts of photovoltaic array and battery storage).

Overview of Photovoltaic Calibration and Measurement Standards at GRC

Science.gov (United States)

Baraona, Cosmo; Snyder, David; Brinker, David; Bailey, Sheila; Curtis, Henry; Scheiman, David; Jenkins, Phillip

2002-01-01

Photovoltaic (PV) systems (cells and arrays) for spacecraft power have become an international market. This market demands accurate prediction of the solar array power output in space throughout the mission life of the spacecraft. Since the beginning of space flight, space-faring nations have independently developed methods to calibrate solar cells for power output in low Earth orbit (LEO). These methods rely on terrestrial, laboratory, or extraterrestrial light sources to simulate or approximate the air mass zero (AM0) solar intensity and spectrum.

Mathematical model for the power generation from arbitrarily oriented photovoltaic panel

Directory of Open Access Journals (Sweden)

Hassan Qusay

2017-01-01

Full Text Available In this paper, a mathematical model for modelling the solar radiation components and photovoltaic arrays power outputs from arbitrarily oriented photovoltaic panel has been presented. Base on the model electrical power prediction of the photovoltaic system in realistic local condition has been presented and compared with experimental measurement. The results show the effectiveness of the proposed model, which provides tools to better understand the performance and reliability as well as decision-making tool in designing of a hybrid renewable energy base power generation system. It has been shown that base on the model prediction, the efficiency and possible failures of the system can be found which are important from the technical and economical point of view.

Photovoltaic and thermal energy conversion for solar powered satellites

Science.gov (United States)

Von Tiesenhausen, G. F.

1976-01-01

A summary is provided concerning the most important aspects of present investigations related to a use of solar power satellites (SPS) as a future source of terrestrial energy. General SPS characteristics are briefly considered, early work is reviewed, and a description of current investigations is presented. System options presently under study include a photovoltaic array, a thermionic system, and a closed Brayton cycle. Attention is given to system reference options, basic building blocks, questions of system analysis and engineering, photovoltaic conversion, and the utility interface. It is concluded that an SPS may be cost effective compared to terrestrial systems by 1995.

Photovoltaic array mounting apparatus, systems, and methods

Science.gov (United States)

West, John Raymond; Atchley, Brian; Hudson, Tyrus Hawkes; Johansen, Emil

2014-12-02

An apparatus for mounting a photovoltaic (PV) module on a surface, including a support with an upper surface, a lower surface, tabs, one or more openings, and a clip comprising an arm and a notch, where the apparatus resists wind forces and seismic forces and creates a grounding electrical bond between the PV module, support, and clip. The invention further includes a method for installing PV modules on a surface that includes arranging supports in rows along an X axis and in columns along a Y axis on a surface such that in each row the distance between two neighboring supports does not exceed the length of the longest side of a PV module and in each column the distance between two neighboring supports does not exceed the length of the shortest side of a PV module.

HgCdTe photovoltaic detectors on Si substrates

International Nuclear Information System (INIS)

Zanio, K.R.; Bean, R.C.

1988-01-01

HgCdTe photovoltaic detectors have been fabricated on Si substrates through intermediate CdTe/GaAs layers. Encapsulation of the GaAs between the CdTe and Si prevents unintentional doping of the HgCdTe by Ga and As. Uniform epitaxial GaAs is grown on three inch diameter Si substrates. Detectors on such large area Si substrates will offer hybrid focal plane arrays whose dimensions are not limited by the difference between the coefficients of thermal expansion of the Si signal processor and the substrate for the HgCdTe detector array. The growth of HgCdTe detectors on the Si signal processors for monolithic focal plane arrays is also considered. 40 references

PARTICLE SWARM OPTIMIZATION BASED OF THE MAXIMUM PHOTOVOLTAIC POWER TRACTIOQG UNDER DIFFERENT CONDITIONS

Directory of Open Access Journals (Sweden)

Y. Labbi

2015-08-01

Full Text Available Photovoltaic electricity is seen as an important source of renewable energy. The photovoltaic array is an unstable source of power since the peak power point depends on the temperature and the irradiation level. A maximum peak power point tracking is then necessary for maximum efficiency.In this work, a Particle Swarm Optimization (PSO is proposed for maximum power point tracker for photovoltaic panel, are used to generate the optimal MPP, such that solar panel maximum power is generated under different operating conditions. A photovoltaic system including a solar panel and PSO MPP tracker is modelled and simulated, it has been has been carried out which has shown the effectiveness of PSO to draw much energy and fast response against change in working conditions.

Study of Photovoltaic Energy Storage by Supercapacitors through Both Experimental and Modelling Approaches

Directory of Open Access Journals (Sweden)

Pierre-Olivier Logerais

2013-01-01

Full Text Available The storage of photovoltaic energy by supercapacitors is studied by using two approaches. An overview on the integration of supercapacitors in solar energy conversion systems is previously provided. First, a realized experimental setup of charge/discharge of supercapacitors fed by a photovoltaic array has been operated with fine data acquisition. The second approach consists in simulating photovoltaic energy storage by supercapacitors with a faithful and accessible model composed of solar irradiance evaluation, equivalent electrical circuit for photovoltaic conversion, and a multibranch circuit for supercapacitor. Both the experimental and calculated results are confronted, and an error of 1% on the stored energy is found with a correction largely within ±10% of the transmission line capacitance according to temperature.

ParaSol - A Novel Deployable Approach for Very Large Ultra-lightweight Solar Arrays, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — High power solar arrays with capabilities of >100kW are needed for projected NASA missions. Photovoltaic arrays using deployable membranes with thin cells have...

Economic optimization of photovoltaic water pumping systems for irrigation

International Nuclear Information System (INIS)

Campana, P.E.; Li, H.; Zhang, J.; Zhang, R.; Liu, J.; Yan, J.

2015-01-01

Highlights: • A novel optimization procedure for photovoltaic water pumping systems for irrigation is proposed. • An hourly simulation model is the basis of the optimization procedure. • The effectiveness of the new optimization approach has been tested to an existing photovoltaic water pumping system. - Abstract: Photovoltaic water pumping technology is considered as a sustainable and economical solution to provide water for irrigation, which can halt grassland degradation and promote farmland conservation in China. The appropriate design and operation significantly depend on the available solar irradiation, crop water demand, water resources and the corresponding benefit from the crop sale. In this work, a novel optimization procedure is proposed, which takes into consideration not only the availability of groundwater resources and the effect of water supply on crop yield, but also the investment cost of photovoltaic water pumping system and the revenue from crop sale. A simulation model, which combines the dynamics of photovoltaic water pumping system, groundwater level, water supply, crop water demand and crop yield, is employed during the optimization. To prove the effectiveness of the new optimization approach, it has been applied to an existing photovoltaic water pumping system. Results show that the optimal configuration can guarantee continuous operations and lead to a substantial reduction of photovoltaic array size and consequently of the investment capital cost and the payback period. Sensitivity studies have been conducted to investigate the impacts of the prices of photovoltaic modules and forage on the optimization. Results show that the water resource is a determinant factor

Electrical research on solar cells and photovoltaic materials

Science.gov (United States)

Orehotsky, J.

1984-01-01

The flat-plate solar cell array program which increases the service lifetime of the photovoltaic modules used for terrestrial energy applications is discussed. The current-voltage response characteristics of the solar cells encapsulated in the modules degrade with service time and this degradation places a limitation on the useful lifetime of the modules. The most desirable flat-plate array system involves solar cells consisting of highly polarizable materials with similar electrochemical potentials where the cells are encapsulated in polymers in which ionic concentrations and mobilities are negligibly small. Another possible mechanism limiting the service lifetime of the photovoltaic modules is the gradual loss of the electrical insulation characteristics of the polymer pottant due to water absorption or due to polymer degradation from light or heat effects. The mechanical properties of various polymer pottant materials and of electrochemical corrosion mechanisms in solar cell material are as follows: (1) electrical and ionic resistivity; (2) water absorption kinetics and water solubility limits; and (3) corrosion characterization of various metallization systems used in solar cell construction.

Examination of a Size-Change Test for Photovoltaic Encapsulation Materials: Preprint

Energy Technology Data Exchange (ETDEWEB)

Miller, D. C.; Wohlgemuth, J. H.; Gu, X.; Ji, L.; Kelly, G.; Gu, X.; Nickel, N.; Norum, P.; Shioda, T.; Tamizhmani, G.

2012-08-01

We examine a proposed test standard that can be used to evaluate the maximum representative change in linear dimensions of sheet encapsulation products for photovoltaic modules (resulting from their thermal processing). The proposed protocol is part of a series of material-level tests being developed within Working Group 2 of the Technical Committee 82 of the International Electrotechnical Commission. The characterization tests are being developed to aid module design (by identifying the essential characteristics that should be communicated on a datasheet), quality control (via internal material acceptance and process control), and failure analysis. Discovery and interlaboratory experiments were used to select particular parameters for the size-change test. The choice of a sand substrate and aluminum carrier is explored relative to other options. The temperature uniformity of +/- 5C for the substrate was confirmed using thermography. Considerations related to the heating device (hot-plate or oven) are explored. The time duration of 5 minutes was identified from the time-series photographic characterization of material specimens (EVA, ionomer, PVB, TPO, and TPU). The test procedure was revised to account for observed effects of size and edges. The interlaboratory study identified typical size-change characteristics, and also verified the absolute reproducibility of +/- 5% between laboratories.

A Simple and Inexpensive Method for Evaluating the Photovoltaic Potential: Its Validation in Buenos Aires and Antarctica

Directory of Open Access Journals (Sweden)

Marcelo D. Cabezas

2016-01-01

Full Text Available The use of renewable energies requires a precise and detailed quantification of the resource available. Because of the cost of solar stations or limited availability of skilled human resources, in most emerging countries, this assessment is made only on a few points scattered over large areas. We report here a simple and inexpensive method to evaluate the photovoltaic (PV potential for a specific geographic region and a given PV capture technology. The system allows for a direct evaluation of the energy actually obtainable by scaling the measurement array of photovoltaic cells. The proposed measurement system can be installed as a stand-alone unit, or as part of a measurement network, connected to a more sophisticated central hub. The measurement station consists of said PV array (or similar PV array, a resistor, and a portable data logger. The system is calibrated with a device composed of a small array of PV cells, a resistor load bank, and two multimeters. Due to its low cost, this system can be replicated as many times as required with minimal investment. This would make it possible to evaluate the available photovoltaic potential of large regions with accurate and detailed data. Measurements carried out in Buenos Aires and in Antarctica confirm the consistency of the method.

Assessment of the technology required to develop photovoltaic power system for large scale national energy applications

Science.gov (United States)

Lutwack, R.

1974-01-01

A technical assessment of a program to develop photovoltaic power system technology for large-scale national energy applications was made by analyzing and judging the alternative candidate photovoltaic systems and development tasks. A program plan was constructed based on achieving the 10 year objective of a program to establish the practicability of large-scale terrestrial power installations using photovoltaic conversion arrays costing less than $0.50/peak W. Guidelines for the tasks of a 5 year program were derived from a set of 5 year objectives deduced from the 10 year objective. This report indicates the need for an early emphasis on the development of the single-crystal Si photovoltaic system for commercial utilization; a production goal of 5 x 10 to the 8th power peak W/year of $0.50 cells was projected for the year 1985. The developments of other photovoltaic conversion systems were assigned to longer range development roles. The status of the technology developments and the applicability of solar arrays in particular power installations, ranging from houses to central power plants, was scheduled to be verified in a series of demonstration projects. The budget recommended for the first 5 year phase of the program is $268.5M.

Low-cost solar array progress and plans

Science.gov (United States)

Callaghan, W. T.

It is pointed out that significant redirection has occurred in the U.S. Department of Energy (DOE) Photovoltaics Program, and thus in the Flat-Plate Solar Array Project (FSA), since the 3rd European Communities Conference. The Silicon Materials Task has now the objective to sponsor theoretical and experimental research on silicon material refinement technology suitable for photovoltaic flat-plate solar arrays. With respect to the hydrochlorination reaction, a process proof of concept was completed through definition of reaction kinetics, catalyst, and reaction characteristics. In connection with the dichlorosilane chemical vapor desposition process, a preliminary design was completed of an experimental process system development unit with a capacity of 100 to 200 MT/yr of Si.Attention is also given to the silicon-sheet formation research area, environmental isolation research, the cell and module formation task, the engineering sciences area, and the module performance and failure analysis area.

Interim performance criteria for photovoltaic energy systems. [Glossary included

Energy Technology Data Exchange (ETDEWEB)

DeBlasio, R.; Forman, S.; Hogan, S.; Nuss, G.; Post, H.; Ross, R.; Schafft, H.

1980-12-01

This document is a response to the Photovoltaic Research, Development, and Demonstration Act of 1978 (P.L. 95-590) which required the generation of performance criteria for photovoltaic energy systems. Since the document is evolutionary and will be updated, the term interim is used. More than 50 experts in the photovoltaic field have contributed in the writing and review of the 179 performance criteria listed in this document. The performance criteria address characteristics of present-day photovoltaic systems that are of interest to manufacturers, government agencies, purchasers, and all others interested in various aspects of photovoltaic system performance and safety. The performance criteria apply to the system as a whole and to its possible subsystems: array, power conditioning, monitor and control, storage, cabling, and power distribution. They are further categorized according to the following performance attributes: electrical, thermal, mechanical/structural, safety, durability/reliability, installation/operation/maintenance, and building/site. Each criterion contains a statement of expected performance (nonprescriptive), a method of evaluation, and a commentary with further information or justification. Over 50 references for background information are also given. A glossary with definitions relevant to photovoltaic systems and a section on test methods are presented in the appendices. Twenty test methods are included to measure performance characteristics of the subsystem elements. These test methods and other parts of the document will be expanded or revised as future experience and needs dictate.

Use Conditions and Efficiency Measurements of DC Power Optimizers for Photovoltaic Systems: Preprint

Energy Technology Data Exchange (ETDEWEB)

Deline, C.; MacAlpine, S.

2013-10-01

No consensus standard exists for estimating annual conversion efficiency of DC-DC converters or power optimizers in photovoltaic (PV) applications. The performance benefits of PV power electronics including per-panel DC-DC converters depend in large part on the operating conditions of the PV system, along with the performance characteristics of the power optimizer itself. This work presents acase study of three system configurations that take advantage of the capabilities of DC power optimizers. Measured conversion efficiencies of DC-DC converters are applied to these scenarios to determine the annual weighted operating efficiency. A simplified general method of reporting weighted efficiency is given, based on the California Energy Commission's CEC efficiency rating and severalinput / output voltage ratios. Efficiency measurements of commercial power optimizer products are presented using the new performance metric, along with a description of the limitations of the approach.

Durability of Poly(Methyl Methacrylate) Lenses Used in Concentrating Photovoltaic Modules: Preprint

Energy Technology Data Exchange (ETDEWEB)

Miller, D. C.; Gedvilas, L. M.; To, B.; Kennedy, C. E.; Kurtz, S. R.

2010-08-01

Concentrating photovoltaic (CPV) technology has recently gained interest based on their expected low levelized cost of electricity, high efficiency, and scalability. Many CPV systems use Fresnel lenses made of poly(methyl methacrylate)(PMMA) to obtain a high optical flux density. The optical and mechanical durability of such components, however, are not well established relative to the desired service life of 30 years. Specific reliability issues may include: reduced optical transmittance, discoloration, hazing, surface erosion, embrittlement, crack growth, physical aging, shape setting (warpage), and soiling. The initial results for contemporary lens- and material-specimens aged cumulatively to 6 months are presented. The study here uses an environmental chamber equipped with a xenon-arc lamp to age specimens at least 8x the nominal field rate. A broad range in the affected characteristics (including optical transmittance, yellowness index, mass loss, and contact angle) has been observed to date, depending on the formulation of PMMA used. The most affected specimens are further examined in terms of their visual appearance, surface roughness (examined via atomic force microscopy), and molecular structure (via Fourier transform infrared spectroscopy).

Operation strategy for a lab-scale grid-connected photovoltaic generation system integrated with battery energy storage

International Nuclear Information System (INIS)

Jou, Hurng-Liahng; Chang, Yi-Hao; Wu, Jinn-Chang; Wu, Kuen-Der

2015-01-01

Highlights: • The operation strategy for grid-connected PV generation system integrated with battery energy storage is proposed. • The PV system is composed of an inverter and two DC-DC converter. • The negative impact of grid-connected PV generation systems on the grid can be alleviated by integrating a battery. • The operation of the developed system can be divided into nine modes. - Abstract: The operation strategy for a lab-scale grid-connected photovoltaic generation system integrated with battery energy storage is proposed in this paper. The photovoltaic generation system is composed of a full-bridge inverter, a DC–DC boost converter, an isolated bidirectional DC–DC converter, a solar cell array and a battery set. Since the battery set acts as an energy buffer to adjust the power generation of the solar cell array, the negative impact on power quality caused by the intermittent and unstable output power from a solar cell array is alleviated, so the penetration rate of the grid-connected photovoltaic generation system is increased. A lab-scale prototype is developed to verify the performance of the system. The experimental results show that it achieves the expected performance

Emergence of highly transparent photovoltaics for distributed applications

Science.gov (United States)

Traverse, Christopher J.; Pandey, Richa; Barr, Miles C.; Lunt, Richard R.

2017-11-01

Solar energy offers a viable solution to our growing energy need. While adoption of conventional photovoltaics on rooftops and in solar farms has grown rapidly in the last decade, there is still plenty of opportunity for expansion. See-through solar technologies with partial light transmission developed over the past 30 years have initiated methods of integration not possible with conventional modules. The large-scale deployment necessary to offset global energy consumption could be further accelerated by developing fully invisible solar cells that selectively absorb ultraviolet and near-infrared light, allowing many of the surfaces of our built environment to be turned into solar harvesting arrays without impacting the function or aesthetics. Here, we review recent advances in photovoltaics with varying degrees of visible light transparency. We discuss the figures of merit necessary to characterize transparent photovoltaics, and outline the requirements to enable their widespread adoption in buildings, windows, electronic device displays, and automobiles.

Intermediate photovoltaic system application experiment operational performance report. Volume 7. Beverly High School, Beverly, MA

Energy Technology Data Exchange (ETDEWEB)

1982-04-01

Performance data are given for a grid-connected photovoltaic power supply at a Massachusetts high school for the month of March, 1982. Data presented include: daily and monthly electrical energy produced; daily and monthly solar energy incident in the array plane; daily and monthly array efficiency; energy produced as a function of power level, voltage, cell temperature, and hour of the day; power conditioner input, output, and efficiency for two power conditioner units and for the overall power conditioning system; daily and monthly photovoltaic energy to load and the corresponding dollar value; grid to load energy from February 17 through April 5; photovoltaic system efficiency; capacity factor; daily system availability; daily and hourly insolation; heating and cooling degree days; hourly and monthly ambient temperature; hourly and monthly wind speed; wind direction distribution; number of freeze/thaw cycles; hourly cell temperature; and data acquisition mode and recording interval plot. Also included are seven summaries of site events. (LEW)

The photovoltaic pilot projects of the European Community

Science.gov (United States)

Schnell, W.

The Commission of the European Communities has started in 1980 a programme for the design and construction of a series of photovoltaic pilot projects in the range of 30-300 kWp. Virtually all important industries and other development organisations in Europe working on photovoltaic cells and systems are involved in this programme. The different technologies which are being developed concern the modules, the cabling of the array, structure design, storage strategy and power conditioning. The various applications include powering of an island, villages, recreation centres, water desalination and disinfection, powering of radio transmitters, emergency power plants, dairy farm, training school, cooling, water pumping, powering of a solar heated swimming pool and last but not least, hydrogen production.

Remote residential photovoltaic systems in British Columbia: A study

Energy Technology Data Exchange (ETDEWEB)

Mathews, R B

1989-01-01

A survey of existing residential photovoltaic power systems in remote areas in British Columbia was conducted to collect data on system performance. The 80 respondents had systems with arrays ranging from 5 to 875 watts, costing from $200 to $14,000. An overwhelming majority of users expressed overall satisfaction with the contribution of photovoltaic technology to their life style. Specific advantages of photovoltaic systems over alternative energy sources included cost-effectiveness, low maintenance, lack of noise and pollution, and ease of operation. Problems with the systems included low winter power, unsatisfactory load matching, and improper operation of associated battery storage systems. It was noted that load profile estimation and system sizing calculations are difficult because control over user behavior with respect to the power system is nearly non-existent when compared to industrial installations. Low-level ampere-hour monitoring of 10 representative sites was carried out and results are presented, giving the power contributions of the photovoltaic system along with any backup system that may be present. Remote residential photovoltaic systems should continue to gain acceptance and more widespread use, especially as module costs drop and more efficient loads (especially appliances such as refrigerators) become practical. 10 figs., 2 tabs.

Bacteria-foraging based-control of high-performance railway level-crossing safety drives fed from photovoltaic array

Directory of Open Access Journals (Sweden)

Essamudin A. Ebrahim

2016-12-01

Full Text Available In the past ten years, railway level-crossing accidents have noticeably escalated in an indisputably preposterous manner, this devastating snag opened the floodgates for the frustrating death of a numerous number of the third world’s citizens, especially in Egypt. To tackle with this problem, a fully intelligent control system is required, which must be automated without human intervention. So, in this research, a new proposed level-crossing tracking system is designed and introduced. The system comprises a high-performance induction motor (IM fed from photovoltaic (PV array, the boom barrier (gate with its mechanism – as a load – buck–boost converter, inverter, and two smart PI-controllers. The first one is designed to regulate the duty cycle of the converter to its optimum value required to balance between maximum power point tracking (MPPT and keeping dc-link voltage of the inverter at a minimum level needed to maintain the motor internal torque at rated value. The second PI-controller is designed for speed control of indirect field-oriented vector-control (IFO-VC IM. The proposed design problems of MPPT, dc-link voltage and speed controllers are solved as optimization problems by bacteria-foraging optimization (BFO algorithm to search for the optimal PI-parameters. The simulation test results are acquired when using the battery-less PV-array with and without the proposed controllers. Also, results are obtained when applying several prescribed speed trajectories to test the robustness against PV-irradiance fluctuations and motor-dynamic disturbances. From these results, the proposed intelligent controllers are robust compared to classical Ziegler–Nichols (ZN PI-controllers and also when the motor is directly fed from PV generator without converter.

Photovoltaic power generation system with photovoltaic cells as bypass diodes

Science.gov (United States)

Lentine, Anthony L.; Nielson, Gregory N.; Tauke-Pedretti, Anna; Cruz-Campa, Jose Luis; Okandan, Murat

2017-11-28

A photovoltaic power generation system that includes a solar panel is described herein. The solar panel includes a photovoltaic sub-module, which includes a group of microsystem enabled photovoltaic cells. The group includes a first string of photovoltaic cells, a second string of photovoltaic cells, and a differing photovoltaic cell. Photovoltaic cells in the first string are electrically connected in series, and photovoltaic cells in the second string are electrically connected in series. Further, the first string of photovoltaic cells, the second string of photovoltaic cells, and the differing photovoltaic cell are electrically connected in parallel. Moreover, the differing photovoltaic cell is used as a bypass diode for the first string of photovoltaic cells and the second string of photovoltaic cells.

Solar Array Panels With Dust-Removal Capability

Science.gov (United States)

Dawson, Stephen; Mardesich, Nick; Spence, Brian; White, Steve

2004-01-01

It has been proposed to incorporate piezoelectric vibrational actuators into the structural supports of solar photovoltaic panels, for the purpose of occasionally inducing vibrations in the panels in order to loosen accumulated dust. Provided that the panels were tilted, the loosened dust would slide off under its own weight. Originally aimed at preventing obscuration of photovoltaic cells by dust accumulating in the Martian environment, the proposal may also offer an option for the design of solar photovoltaic panels for unattended operation at remote locations on Earth. The figure depicts a typical lightweight solar photovoltaic panel comprising a backside grid of structural spars that support a thin face sheet that, in turn, supports an array of photovoltaic cells on the front side. The backside structure includes node points where several spars intersect. According to the proposal, piezoelectric buzzers would be attached to the node points. The process of designing the panel would be an iterative one that would include computational simulation of the vibrations by use of finite- element analysis to guide the selection of the vibrational frequency of the actuators and the cross sections of the spars to maximize the agitation of dust.

The performance analysis of the Trough Concentrating Solar Photovoltaic/Thermal system

Energy Technology Data Exchange (ETDEWEB)

Li, M., E-mail: liming@ynnu.edu.c [Solar Energy Research Institute, Yunnan Normal University, 650092 Kunming (China); Li, G.L. [School of Physics and Electronic Information, Yunnan Normal University, Kunming 650092 (China); Ji, X.; Yin, F.; Xu, L. [Solar Energy Research Institute, Yunnan Normal University, 650092 Kunming (China)

2011-06-15

Research highlights: {yields} A 2 m{sup 2} Trough Concentrating Photovoltaic/Thermal (TCPV/T) system is built, a single crystalline silicon solar cell array, a polycrystalline silicon cell array, a Super cell array and a GaAs cell array are respectively used in the experiments. {yields} Another 10 m{sup 2} TCPV/T system using the GaAs cell array and a concentrating silicon cell array are also constructed and characterized. {yields} The economic performance analysis show the electricity generating cost of the TCPV/T system with the concentrating silicon cell array can catch up with flat-plate PV system. -- Abstract: The electrical and thermal performance of a 2 m{sup 2} Trough Concentrating Photovoltaic/Thermal (TCPV/T) system with an energy flux ratio 10.27 are characterized by experiments. A single crystalline silicon solar cell array, a polycrystalline silicon cell array, a Super cell array and a GaAs cell array are respectively used in the experiments. The experimental results show that the electrical performance of the system with the GaAs cell array is better than that of crystal silicon solar cell arrays. The superior output performance of the GaAs cell array mainly benefits from its lower series resistance. But the thermal performances of the system using the single crystal silicon solar cell array and the polycrystalline silicon solar cell array are better. It results from the widths of the two types of cells in the system close to that of the focal line. Another 10 m{sup 2} TCPV/T system with an energy flux ratio of 20 using the GaAs cell array and a concentrating silicon cell array are also constructed and characterized. The experimental results indicate that the photoelectric efficiency of the GaAs cell array is 23.83%, and the instantaneous electrical efficiency and thermal efficiency of the system are 9.88% and 49.84% respectively. While the instantaneous electrical efficiency and thermal efficiency of the system using the low-cost concentrating

The performance analysis of the Trough Concentrating Solar Photovoltaic/Thermal system

International Nuclear Information System (INIS)

Li, M.; Li, G.L.; Ji, X.; Yin, F.; Xu, L.

2011-01-01

Research highlights: → A 2 m 2 Trough Concentrating Photovoltaic/Thermal (TCPV/T) system is built, a single crystalline silicon solar cell array, a polycrystalline silicon cell array, a Super cell array and a GaAs cell array are respectively used in the experiments. → Another 10 m 2 TCPV/T system using the GaAs cell array and a concentrating silicon cell array are also constructed and characterized. → The economic performance analysis show the electricity generating cost of the TCPV/T system with the concentrating silicon cell array can catch up with flat-plate PV system. -- Abstract: The electrical and thermal performance of a 2 m 2 Trough Concentrating Photovoltaic/Thermal (TCPV/T) system with an energy flux ratio 10.27 are characterized by experiments. A single crystalline silicon solar cell array, a polycrystalline silicon cell array, a Super cell array and a GaAs cell array are respectively used in the experiments. The experimental results show that the electrical performance of the system with the GaAs cell array is better than that of crystal silicon solar cell arrays. The superior output performance of the GaAs cell array mainly benefits from its lower series resistance. But the thermal performances of the system using the single crystal silicon solar cell array and the polycrystalline silicon solar cell array are better. It results from the widths of the two types of cells in the system close to that of the focal line. Another 10 m 2 TCPV/T system with an energy flux ratio of 20 using the GaAs cell array and a concentrating silicon cell array are also constructed and characterized. The experimental results indicate that the photoelectric efficiency of the GaAs cell array is 23.83%, and the instantaneous electrical efficiency and thermal efficiency of the system are 9.88% and 49.84% respectively. While the instantaneous electrical efficiency and thermal efficiency of the system using the low-cost concentrating silicon cell array are 7.51% and 42

Comparative Performance and Model Agreement of Three Common Photovoltaic Array Configurations.

Science.gov (United States)

Boyd, Matthew T

2018-02-01

Three grid-connected monocrystalline silicon arrays on the National Institute of Standards and Technology (NIST) campus in Gaithersburg, MD have been instrumented and monitored for 1 yr, with only minimal gaps in the data sets. These arrays range from 73 kW to 271 kW, and all use the same module, but have different tilts, orientations, and configurations. One array is installed facing east and west over a parking lot, one in an open field, and one on a flat roof. Various measured relationships and calculated standard metrics have been used to compare the relative performance of these arrays in their different configurations. Comprehensive performance models have also been created in the modeling software pvsyst for each array, and its predictions using measured on-site weather data are compared to the arrays' measured outputs. The comparisons show that all three arrays typically have monthly performance ratios (PRs) above 0.75, but differ significantly in their relative output, strongly correlating to their operating temperature and to a lesser extent their orientation. The model predictions are within 5% of the monthly delivered energy values except during the winter months, when there was intermittent snow on the arrays, and during maintenance and other outages.

Ultralightweight PV Array Materials for Deep Space Mission Environments, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Photovoltaic arrays for future deep space NASA missions demand multiple functionalities. They must efficiently generate electrical power, have very large areas and...

Evaluation of Crack and Corrosion Detection Sensitivity Using Piezoelectric Sensor Arrays (Preprint)

National Research Council Canada - National Science Library

Blackshire, James L; Martin, Steve; Cooney, Adam

2006-01-01

.... In this research effort, a systematic evaluation of the detection sensitivity levels of surface-bonded piezoelectric sensor arrays has been undertaken using experimental studies and analytic modeling...

Stand-alone flat-plate photovoltaic power systems: System sizing and life-cycle costing methodology for Federal agencies

Science.gov (United States)

Borden, C. S.; Volkmer, K.; Cochrane, E. H.; Lawson, A. C.

1984-01-01

A simple methodology to estimate photovoltaic system size and life-cycle costs in stand-alone applications is presented. It is designed to assist engineers at Government agencies in determining the feasibility of using small stand-alone photovoltaic systems to supply ac or dc power to the load. Photovoltaic system design considerations are presented as well as the equations for sizing the flat-plate array and the battery storage to meet the required load. Cost effectiveness of a candidate photovoltaic system is based on comparison with the life-cycle cost of alternative systems. Examples of alternative systems addressed are batteries, diesel generators, the utility grid, and other renewable energy systems.

Novel photon management for thin-film photovoltaics

Energy Technology Data Exchange (ETDEWEB)

Menon, Rajesh [Univ. of Utah, Salt Lake City, UT (United States)

2016-11-11

The objective of this project is to enable commercially viable thin-film photovoltaics whose efficiencies are increased by over 10% using a novel optical spectral-separation technique. A thin planar diffractive optic is proposed that efficiently separates the solar spectrum and assigns these bands to optimal thin-film sub-cells. An integrated device that is comprised of the optical element, an array of sub-cells and associated packaging is proposed.

Online Variable Topology-Type Photovoltaic Grid-Connected Inverter

DEFF Research Database (Denmark)

Wu, Fengjiang; Sun, Bo; Duan, Jiandong

2015-01-01

In photovoltaic (PV) grid-connected generation system, the key focus is how to expand the generation range of the PV array and enhance the total efficiency of the system. This paper originally derived expressions of the total loss and grid current total harmonics distortions of cascaded inverter...... and H-bridge inverter under the conditions of variable output voltage and power of the PV array. It is proved that, compared with the H-bridge inverter, the operation range of the cascaded inverter is wider, whereas the total loss is larger. Furthermore, a novel online variable topology-type grid......-connected inverter is proposed. A bidirectional power switch is introduced into the conventional cascaded inverter to connect the negative terminals of the PV arrays. When the output voltages of the PV arrays are lower, the proposed inverter works under cascaded inverter mode to obtain wider generation range. When...

A feasibility and load sensitivity analysis of photovoltaic water pumping system with battery and diesel generator

International Nuclear Information System (INIS)

Muhsen, Dhiaa Halboot; Khatib, Tamer; Haider, Haider Tarish

2017-01-01

Highlights: • Feasibility and load sensitivity analysis is conducted for PVPS. • Battery and diesel generator are considered as supporting units to the system. • The configuration of the PV array and the initial status of the tank are important. • The COU is more sensitive to the capital cost of PV array than other components. • Increasing the maximum capacity of water storage tank is better storage and DG. - Abstract: In this paper, a feasibility and load sensitivity analysis is conducted for photovoltaic water pumping systems with storage device (battery) or diesel generator so as to obtain an optimal configuration that achieves a reliable system. The analysis is conducted based on techno-economic aspects, where the loss of load probability and life cycle cost are represented as technical and economic criteria, respectively. Various photovoltaic water pumping systems scenarios with initially full storage tank; battery and hybrid DG-PV energy source are proposed to analyze the feasibility of system. The result shows that the configuration of the PV array and the initial status of the storage tank are important variables to be considered. Moreover, the sensitivity of cost of unit for various PVPS components is studied. It is found that the cost of unit is more sensitive to the initial capital cost of photovoltaic array than other components. In this paper a standalone PV based pumping system with a PV array capacity of 2.4 kWp and a storage tank with a capacity of 80 m 3 was proposed an a optimum system. The system with the aforementioned configuration pumps an average hourly water volume of approximately 3.297 m 3 over one year with a unit of 0.05158 USD/m 3 . Moreover, according to results, increasing the maximum capacity of water storage tank is technically and economically better than supporting a photovoltaic water pumping systems with another energy source or extra storage device.

Game-Changing Photovoltaic Flexible Blanket Solar Array Technology with Spectrolab Flexsheets, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Deployable Space Systems, Inc. (DSS) in collaboration with Spectrolab, Inc. has developed a modular multi-junction photovoltaic flexible blanket technology that uses...

Estimating the Effects of Module Area on Thin-Film Photovoltaic System Costs: Preprint

Energy Technology Data Exchange (ETDEWEB)

Horowitz, Kelsey A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Fu, Ran [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Silverman, Timothy J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Woodhouse, Michael A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Sun, Xingshu [Purdue University; Alam, Muhammad A [Purdue University

2018-03-29

We investigate the potential effects of module area on the cost and performance of photovoltaic systems. Applying a bottom-up methodology, we analyzed the costs associated with thin-film modules and systems as a function of module area. We calculate a potential for savings of up to 0.10 dollars/W and 0.13 dollars/W in module manufacturing costs for CdTe and CIGS respectively, with large area modules. We also find that an additional 0.04 dollars/W savings in balance-of-systems costs may be achieved. Sensitivity of the dollar/W cost savings to module efficiency, manufacturing yield, and other parameters is presented. Lifetime energy yield must also be maintained to realize reductions in the levelized cost of energy; the effects of module size on energy yield for monolithic thin-film modules are not yet well understood. Finally, we discuss possible non-cost barriers to adoption of large area modules.

Solution processable organic/inorganic hybrid ultraviolet photovoltaic detector

Directory of Open Access Journals (Sweden)

Xiaopeng Guo

2016-05-01

Full Text Available Ultraviolet (UV photodetector is a kind of important optoelectronic device which can be widely used in scientific and engineering fields including astronomical research, environmental monitoring, forest-fire prevention, medical analysis, and missile approach warning etc. The development of UV detector is hindered by the acquirement of stable p-type materials, which makes it difficult to realize large array, low-power consumption UV focal plane array (FPA detector. Here, we provide a novel structure (Al/Poly(9,9-di-n-octylfuorenyl-2,7-diyl(PFO/ZnO/ITO to demonstrate the UV photovoltaic (PV response. A rather smooth surface (RMS roughness: 0.28 nm may be reached by solution process, which sheds light on the development of large-array, light-weight and low-cost UV FPA detectors.

Series Resistance Monitoring for Photovoltaic Modules in the Vicinity of MPP

DEFF Research Database (Denmark)

Sera, Dezso

2010-01-01

Faults and performance deterioration issues related to increases of the series resistance in PV modules or arrays are one of the most common causes to decrease the energy yield of photovoltaic installations. Therefore, the early detection of such failure types is very important in order to minimize...

Preprint WebVRGIS Based Traffic Analysis and Visualization System

OpenAIRE

Li, Xiaoming; Lv, Zhihan; Wang, Weixi; Zhang, Baoyun; Hu, Jinxing; Yin, Ling; Feng, Shengzhong

2015-01-01

This is the preprint version of our paper on Advances in Engineering Software. With several characteristics, such as large scale, diverse predictability and timeliness, the city traffic data falls in the range of definition of Big Data. A Virtual Reality GIS based traffic analysis and visualization system is proposed as a promising and inspiring approach to manage and develop traffic big data. In addition to the basic GIS interaction functions, the proposed system also includes some intellige...

Photovoltaic module and interlocked stack of photovoltaic modules

Science.gov (United States)

Wares, Brian S.

2014-09-02

One embodiment relates to an arrangement of photovoltaic modules configured for transportation. The arrangement includes a plurality of photovoltaic modules, each photovoltaic module including a frame. A plurality of individual male alignment features and a plurality of individual female alignment features are included on each frame. Adjacent photovoltaic modules are interlocked by multiple individual male alignment features on a first module of the adjacent photovoltaic modules fitting into and being surrounded by corresponding individual female alignment features on a second module of the adjacent photovoltaic modules. Other embodiments, features and aspects are also disclosed.

A 194 kilowatt solar photovoltaic flat panel power system for the combined Beverly High School/C. H. Patten Vocational High School, Beverly, Massachusetts

Science.gov (United States)

Addiss, R. R., Jr.; Lawson, P. A.

1980-06-01

The design and performance of a photovoltaic power system is discussed. The 194 kW system consists of the photovoltaic array, the inverter/control subsystem, the building and utility interface, and the monitoring subsystem. The photovoltaic array consists of 56 separate subarrays of 112 photovoltaic modules each, deployed in rows on the southerly facing slope north of the school building. The wiring scheme permits individual modules to be disconnected without a radical change in subarray output current. Power is transmitted at 4160 V from the inverters and a step up transformer to the main 4160 V utility feed line in the school. Separate metering measures power bought and sold. At the optimum tilt angle of 40 deg, the array provides 232 MWH of AC energy annually, or 17 percent of the school load. The immediate impact is an $8000 saving in the annual utility bill. Levelized busbar energy costs are reduced from $2/kWH to $1/kWH when site specific parameters are used in the analysis instead of the JPL specified nominal values. A fault detection and isolation scheme which can find a single modulus failure is incorporated into the monitoring subsystem.

Enhanced photovoltaic performance of an inclined nanowire array solar cell.

Science.gov (United States)

Wu, Yao; Yan, Xin; Zhang, Xia; Ren, Xiaomin

2015-11-30

An innovative solar cell based on inclined p-i-n nanowire array is designed and analyzed. The results show that the inclined geometry can sufficiently increase the conversion efficiency of solar cells by enhancing the absorption of light in the active region. By tuning the nanowire array density, nanowire diameter, nanowire length, as well as the proportion of intrinsic region of the inclined nanowire solar cell, a remarkable efficiency in excess of 16% can be obtained in GaAs. Similar results have been obtained in InP and Si nanowire solar cells, demonstrating the universality of the performance enhancement of inclined nanowire arrays.

GaAs nanopillar-array solar cells employing in situ surface passivation

Science.gov (United States)

Mariani, Giacomo; Scofield, Adam C.; Hung, Chung-Hong; Huffaker, Diana L.

2013-01-01

Arrays of III–V direct-bandgap semiconductor nanopillars represent promising photovoltaic candidates due to their inherent high optical absorption coefficients and minimized reflection arising from light trapping, efficient charge collection in the radial direction and the ability to synthesize them on low-cost platforms. However, the increased surface area results in surface states that hamper the power conversion efficiency. Here, we report the first demonstration of GaAs nanopillar-array photovoltaics employing epitaxial passivation with air mass 1.5 global power conversion efficiencies of 6.63%. High-bandgap epitaxial InGaP shells are grown in situ and cap the radial p–n junctions to alleviate surface-state effects. Under light, the photovoltaic devices exhibit open-circuit voltages of 0.44 V, short-circuit current densities of 24.3 mA cm−2 and fill factors of 62% with high external quantum efficiencies >70% across the spectral regime of interest. A novel titanium/indium tin oxide annealed alloy is exploited as transparent ohmic anode. PMID:23422665

Distributed photovoltaic systems - Addressing the utility interface issues

Science.gov (United States)

Firstman, S. I.; Vachtsevanos, G. J.

This paper reviews work conducted in the United States on the impact of dispersed photovoltaic sources upon utility operations. The photovoltaic (PV) arrays are roof-mounted on residential houses and connected, via appropriate power conditioning equipment, to the utility grid. The presence of such small (4-6 Kw) dispersed generators on the distribution network raises questions of a technical, economic and institutional nature. After a brief identification of utility interface issues, the paper addresses such technical concerns as protection of equipment and personnel safety, power quality and utility operational stability. A combination of experimental and analytical approaches has been adopted to arrive at solutions to these problems. Problem areas, under various PV system penetration scenarios, are identified and conceptual designs of protection and control equipment and operating policies are developed so that system reliability is maintained while minimizing capital costs. It is hoped that the resolution of balance-of-system and grid interface questions will ascertain the economic viability of photovoltaic systems and assist in their widespread utilization in the future.

The photovoltaic industry between growth and difficulties

International Nuclear Information System (INIS)

2013-01-01

This article proposes an overview of the situation and trends of the photovoltaic industry sector. If half of the market was shared among few German, Chinese and American companies in 2010, it appears that half of photovoltaic cells and arrays were designed and manufactured in China in 2013. The European Union and the USA therefore introduced taxes on these products. As this sector appears to be a strategic one, this resulted in a new support for this industry by the Chinese government. The article then comments the French market: slow development in terms of energy production as well as in terms of equipment manufacturing. Thus, measures taken by the French government resulted in a diversification of products, but cost of production of electricity remains high. Perspectives are finally evoked, notably in Japan after the Fukushima accident

White butterflies as solar photovoltaic concentrators

Science.gov (United States)

Shanks, Katie; Senthilarasu, S.; Ffrench-Constant, Richard H.; Mallick, Tapas K.

2015-07-01

Man’s harvesting of photovoltaic energy requires the deployment of extensive arrays of solar panels. To improve both the gathering of thermal and photovoltaic energy from the sun we have examined the concept of biomimicry in white butterflies of the family Pieridae. We tested the hypothesis that the V-shaped posture of basking white butterflies mimics the V-trough concentrator which is designed to increase solar input to photovoltaic cells. These solar concentrators improve harvesting efficiency but are both heavy and bulky, severely limiting their deployment. Here, we show that the attachment of butterfly wings to a solar cell increases its output power by 42.3%, proving that the wings are indeed highly reflective. Importantly, and relative to current concentrators, the wings improve the power to weight ratio of the overall structure 17-fold, vastly expanding their potential application. Moreover, a single mono-layer of scale cells removed from the butterflies’ wings maintained this high reflectivity showing that a single layer of scale cell-like structures can also form a useful coating. As predicted, the wings increased the temperature of the butterflies’ thorax dramatically, showing that the V-shaped basking posture of white butterflies has indeed evolved to increase the temperature of their flight muscles prior to take-off.

White butterflies as solar photovoltaic concentrators.

Science.gov (United States)

Shanks, Katie; Senthilarasu, S; Ffrench-Constant, Richard H; Mallick, Tapas K

2015-07-31

Man's harvesting of photovoltaic energy requires the deployment of extensive arrays of solar panels. To improve both the gathering of thermal and photovoltaic energy from the sun we have examined the concept of biomimicry in white butterflies of the family Pieridae. We tested the hypothesis that the V-shaped posture of basking white butterflies mimics the V-trough concentrator which is designed to increase solar input to photovoltaic cells. These solar concentrators improve harvesting efficiency but are both heavy and bulky, severely limiting their deployment. Here, we show that the attachment of butterfly wings to a solar cell increases its output power by 42.3%, proving that the wings are indeed highly reflective. Importantly, and relative to current concentrators, the wings improve the power to weight ratio of the overall structure 17-fold, vastly expanding their potential application. Moreover, a single mono-layer of scale cells removed from the butterflies' wings maintained this high reflectivity showing that a single layer of scale cell-like structures can also form a useful coating. As predicted, the wings increased the temperature of the butterflies' thorax dramatically, showing that the V-shaped basking posture of white butterflies has indeed evolved to increase the temperature of their flight muscles prior to take-off.

High-Performance GaAs Nanowire Solar Cells for Flexible and Transparent Photovoltaics.

Science.gov (United States)

Han, Ning; Yang, Zai-xing; Wang, Fengyun; Dong, Guofa; Yip, SenPo; Liang, Xiaoguang; Hung, Tak Fu; Chen, Yunfa; Ho, Johnny C

2015-09-16

Among many available photovoltaic technologies at present, gallium arsenide (GaAs) is one of the recognized leaders for performance and reliability; however, it is still a great challenge to achieve cost-effective GaAs solar cells for smart systems such as transparent and flexible photovoltaics. In this study, highly crystalline long GaAs nanowires (NWs) with minimal crystal defects are synthesized economically by chemical vapor deposition and configured into novel Schottky photovoltaic structures by simply using asymmetric Au-Al contacts. Without any doping profiles such as p-n junction and complicated coaxial junction structures, the single NW Schottky device shows a record high apparent energy conversion efficiency of 16% under air mass 1.5 global illumination by normalizing to the projection area of the NW. The corresponding photovoltaic output can be further enhanced by connecting individual cells in series and in parallel as well as by fabricating NW array solar cells via contact printing showing an overall efficiency of 1.6%. Importantly, these Schottky cells can be easily integrated on the glass and plastic substrates for transparent and flexible photovoltaics, which explicitly demonstrate the outstanding versatility and promising perspective of these GaAs NW Schottky photovoltaics for next-generation smart solar energy harvesting devices.

Geometrical optics, electrostatics, and nanophotonic resonances in absorbing nanowire arrays.

Science.gov (United States)

Anttu, Nicklas

2013-03-01

Semiconductor nanowire arrays have shown promise for next-generation photovoltaics and photodetection, but enhanced understanding of the light-nanowire interaction is still needed. Here, we study theoretically the absorption of light in an array of vertical InP nanowires by moving continuously, first from the electrostatic limit to the nanophotonic regime and then to the geometrical optics limit. We show how the absorption per volume of semiconductor material in the array can be varied by a factor of 200, ranging from 10 times weaker to 20 times stronger than in a bulk semiconductor sample.

Field Guide for Testing Existing Photovoltaic Systems for Ground Faults and Installing Equipment to Mitigate Fire Hazards

Energy Technology Data Exchange (ETDEWEB)

Brooks, William [Brooks Engineering, Vacaville, CA (United States); Basso, Thomas [National Renewable Energy Lab. (NREL), Golden, CO (United States); Coddington, Michael [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2015-10-01

Ground faults and arc faults are the two most common reasons for fires in photovoltaic (PV) arrays and methods exist that can mitigate the hazards. This report provides field procedures for testing PV arrays for ground faults, and for implementing high resolution ground fault and arc fault detectors in existing and new PV system designs.

Photovoltaic module encapsulation design and materials selection, volume 1

Science.gov (United States)

Cuddihy, E.; Carroll, W.; Coulbert, C.; Gupta, A.; Liang, R. H.

1982-01-01

Encapsulation material system requirements, material selection criteria, and the status and properties of encapsulation materials and processes available are presented. Technical and economic goals established for photovoltaic modules and encapsulation systems and their status are described. Available encapsulation technology and data are presented to facilitate design and material selection for silicon flat plate photovoltaic modules, using the best materials available and processes optimized for specific power applications and geographic sites. The operational and environmental loads that encapsulation system functional requirements and candidate design concepts and materials that are identified to have the best potential to meet the cost and performance goals for the flat plate solar array project are described. Available data on encapsulant material properties, fabrication processing, and module life and durability characteristics are presented.

Modelling of storage of the photovoltaic energy by super-capacitors

International Nuclear Information System (INIS)

Camara, Mohamed Ansoumane

2011-01-01

The storage by ultra-capacitors of photovoltaic energy is modeled in order to have an accurate and accessible model to integrate ultra-capacitors into solar energy conversion systems. Ultra-capacitors are modeled by a multi-branch circuit representation composed of resistors and capacitors with variable voltage whose values are determined by an accurate characterization experiment. Moreover, all the elements of a typical photovoltaic energy conversion system are modeled by using the Matlab/Simulink software (solar radiation, photovoltaic arrays, regulator, batteries and charges). The energy storage model by ultra-capacitors is then validated by the good agreement of measured values taken in real conditions with the results provided by simulations. Finally, two examples are proposed and discussed: the determination of the storage duration of ultra-capacitors versus solar irradiance and ambient temperature, and the integration of ultra-capacitors in the electrical feeding system of a DC motor to reduce the electrical current peak of the battery at the start of the motor. (author) [fr

FPGA-based implementation of a fuzzy controller (MPPT) for photovoltaic module

International Nuclear Information System (INIS)

Messai, A.; Mellit, A.; Massi Pavan, A.; Guessoum, A.; Mekki, H.

2011-01-01

Research highlights: → FL-MPPT controller is implemented on FPGA. → Results obtained with ModelSim show a satisfactory performance. → Results will be useful for future development in PV. -- Abstract: This paper describes the hardware implementation of a two-inputs one-output digital Fuzzy Logic Controller (FLC) on a Xilinx reconfigurable Field-Programmable Gate Array (FPGA) using VHDL Hardware Description Language. The FLC is designed for seeking the maximum power point deliverable by a photovoltaic module using the measures of the photovoltaic current and voltage. The simulation results obtained with ModelSim Xilinx Edition-III show a satisfactory performance with a good agreement between the expected and the obtained values.

FPGA-based implementation of a fuzzy controller (MPPT) for photovoltaic module

Energy Technology Data Exchange (ETDEWEB)

Messai, A. [CRNB Ain Oussera, P.O. Box 180, 17200, Djelfa (Algeria); Department of Electronics, Faculty of Sciences Engineering, Blida University, Blida 90000 (Algeria); Mellit, A., E-mail: a.mellit@yahoo.co.u [Department of Electronics, Faculty of Sciences and Technology, Jijel University, Ouled-aissa, P.O. Box 98, Jijel 18000 (Algeria); Department of Electronics, Faculty of Sciences Engineering, Blida University, Blida 90000 (Algeria); Massi Pavan, A. [Department of Materials and Natural Resources, University of Trieste, Via A. Valerio, 2 - 34127 Trieste (Italy); Guessoum, A. [Department of Electronics, Faculty of Sciences Engineering, Blida University, Blida 90000 (Algeria); Mekki, H. [CRNB Ain Oussera, P.O. Box 180, 17200, Djelfa (Algeria); Department of Electronics, Faculty of Sciences Engineering, Blida University, Blida 90000 (Algeria)

2011-07-15

Research highlights: {yields} FL-MPPT controller is implemented on FPGA. {yields} Results obtained with ModelSim show a satisfactory performance. {yields} Results will be useful for future development in PV. -- Abstract: This paper describes the hardware implementation of a two-inputs one-output digital Fuzzy Logic Controller (FLC) on a Xilinx reconfigurable Field-Programmable Gate Array (FPGA) using VHDL Hardware Description Language. The FLC is designed for seeking the maximum power point deliverable by a photovoltaic module using the measures of the photovoltaic current and voltage. The simulation results obtained with ModelSim Xilinx Edition-III show a satisfactory performance with a good agreement between the expected and the obtained values.

Design and performance of the Georgia Tech Aquatic Center photovoltaic system. Final report

Energy Technology Data Exchange (ETDEWEB)

Rohatgi, A.; Begovic, M.; Long, R.; Ropp, M.; Pregelj, A.

1996-12-31

A building-integrated DC PV array has been constructed on the Georgia Tech campus. The array is mounted on the roof of the Georgia Tech Aquatic Center (GTAC), site of the aquatic events during the 1996 Paralympic and Olympic Games in Atlanta. At the time of its construction, it was the world`s largest roof-mounted photovoltaic array, comprised of 2,856 modules and rates at 342 kW. This section describes the electrical and physical layout of the PV system, and the associated data acquisition system (DAS) which monitors the performance of the system and collects measurements of several important meteorological parameters.

Preliminary Design of a Solar Photovoltaic Array for Net-Zero Energy Buildings at NASA Langley

Science.gov (United States)

Cole, Stuart K.; DeYoung, Russell J.

2012-01-01

An investigation was conducted to evaluate photovoltaic (solar electric systems) systems for a single building at NASA Langley as a representative case for alternative sustainable power generation. Building 1250 in the Science Directorate is comprised of office and laboratory space, and currently uses approximately 250,000 kW/month of electrical power with a projected use of 200,000 kW/month with additional conservation measures. The installation would be applied towards a goal for having Building 1250 classified as a net-zero energy building as it would produce as much energy as it uses over the course of a year. Based on the facility s electrical demand, a photovoltaic system and associated hardware were characterized to determine the optimal system, and understand the possible impacts from its deployment. The findings of this investigation reveal that the 1.9 MW photovoltaic electrical system provides favorable and robust results. The solar electric system should supply the needed sustainable power solution especially if operation and maintenance of the system will be considered a significant component of the system deployment.

High density micro-pyramids with silicon nanowire array for photovoltaic applications

International Nuclear Information System (INIS)

Rahman, Tasmiat; Navarro-Cía, Miguel; Fobelets, Kristel

2014-01-01

We use a metal assisted chemical etch process to fabricate silicon nanowire arrays (SiNWAs) onto a dense periodic array of pyramids that are formed using an alkaline etch masked with an oxide layer. The hybrid micro-nano structure acts as an anti-reflective coating with experimental reflectivity below 1% over the visible and near-infrared spectral regions. This represents an improvement of up to 11 and 14 times compared to the pyramid array and SiNWAs on bulk, respectively. In addition to the experimental work, we optically simulate the hybrid structure using a commercial finite difference time domain package. The results of the optical simulations support our experimental work, illustrating a reduced reflectivity in the hybrid structure. The nanowire array increases the absorbed carrier density within the pyramid by providing a guided transition of the refractive index along the light path from air into the silicon. Furthermore, electrical simulations which take into account surface and Auger recombination show an efficiency increase for the hybrid structure of 56% over bulk, 11% over pyramid array and 8.5% over SiNWAs. (paper)

A New Approach for Optimal Sizing of Standalone Photovoltaic Systems

Directory of Open Access Journals (Sweden)

Tamer Khatib

2012-01-01

Full Text Available This paper presents a new method for determining the optimal sizing of standalone photovoltaic (PV system in terms of optimal sizing of PV array and battery storage. A standalone PV system energy flow is first analysed, and the MATLAB fitting tool is used to fit the resultant sizing curves in order to derive general formulas for optimal sizing of PV array and battery. In deriving the formulas for optimal sizing of PV array and battery, the data considered are based on five sites in Malaysia, which are Kuala Lumpur, Johor Bharu, Ipoh, Kuching, and Alor Setar. Based on the results of the designed example for a PV system installed in Kuala Lumpur, the proposed method gives satisfactory optimal sizing results.

Photovoltaic generator with a spherical imaging lens for use with a paraboloidal solar reflector

Science.gov (United States)

Angel, Roger P

2013-01-08

The invention is a generator for photovoltaic conversion of concentrated sunlight into electricity. A generator according to the invention incorporates a plurality of photovoltaic cells and is intended for operation near the focus of a large paraboloidal reflector pointed at the sun. Within the generator, the entering concentrated light is relayed by secondary optics to the cells arranged in a compact, concave array. The light is delivered to the cells at high concentration, consistent with high photovoltaic conversion efficiency and low cell cost per unit power output. Light enters the generator, preferably first through a sealing window, and passes through a field lens, preferably in the form of a full sphere or ball lens centered on the paraboloid focus. This lens forms a concentric, concave and wide-angle image of the primary reflector, where the intensity of the concentrated light is stabilized against changes in the position of concentrated light entering the generator. Receiving the stabilized light are flat photovoltaic cells made in different shapes and sizes and configured in a concave array corresponding to the concave image of a given primary reflector. Photovoltaic cells in a generator are also sized and interconnected so as to provide a single electrical output that remains high and stable, despite aberrations in the light delivered to the generator caused by, for example, mispointing or bending of the primary reflector. In some embodiments, the cells are set back from the image formed by the ball lens, and part of the light is reflected onto each cell small secondary reflectors in the form of mirrors set around its perimeter.

Reflective photovoltaics

Energy Technology Data Exchange (ETDEWEB)

Lentine, Anthony L.; Nielson, Gregory N.; Cruz-Campa, Jose Luis; Okandan, Murat; Goeke, Ronald S.

2018-03-06

A photovoltaic module includes colorized reflective photovoltaic cells that act as pixels. The colorized reflective photovoltaic cells are arranged so that reflections from the photovoltaic cells or pixels visually combine into an image on the photovoltaic module. The colorized photovoltaic cell or pixel is composed of a set of 100 to 256 base color sub-pixel reflective segments or sub-pixels. The color of each pixel is determined by the combination of base color sub-pixels forming the pixel. As a result, each pixel can have a wide variety of colors using a set of base colors, which are created, from sub-pixel reflective segments having standard film thicknesses.

Technical evaluation of Solar Cells, Inc., CdTe module and array at NREL

Energy Technology Data Exchange (ETDEWEB)

Kroposki, B.; Strand, T.; Hansen, R. [National Renewable Energy Lab., Golden, CO (United States); Powell, R.; Sasala, R. [Solar Cells, Inc., Toledo, OH (United States)

1996-05-01

The Engineering and Technology Validation Team at the National Renewable Energy Laboratory (NREL) conducts in-situ technical evaluations of polycrystalline thin-film photovoltaic (PV) modules and arrays. This paper focuses on the technical evaluation of Solar Cells, Inc., (SCI) cadmium telluride (CdTe) module and array performance by attempting to correlate individual module and array performance. This is done by examining the performance and stability of the modules and array over a period of more than one year. Temperature coefficients for module and array parameters (P{sub max}, V{sub oc}, V{sub max}, I{sub sc}, I{sub max}) are also calculated.

Photovoltaic solar concentrator

Science.gov (United States)

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

2015-09-08

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

Spatiotemporal characteristics of retinal response to network-mediated photovoltaic stimulation.

Science.gov (United States)

Ho, Elton; Smith, Richard; Goetz, Georges; Lei, Xin; Galambos, Ludwig; Kamins, Theodore I; Harris, James; Mathieson, Keith; Palanker, Daniel; Sher, Alexander

2018-02-01

Subretinal prostheses aim at restoring sight to patients blinded by photoreceptor degeneration using electrical activation of the surviving inner retinal neurons. Today, such implants deliver visual information with low-frequency stimulation, resulting in discontinuous visual percepts. We measured retinal responses to complex visual stimuli delivered at video rate via a photovoltaic subretinal implant and by visible light. Using a multielectrode array to record from retinal ganglion cells (RGCs) in the healthy and degenerated rat retina ex vivo, we estimated their spatiotemporal properties from the spike-triggered average responses to photovoltaic binary white noise stimulus with 70-μm pixel size at 20-Hz frame rate. The average photovoltaic receptive field size was 194 ± 3 μm (mean ± SE), similar to that of visual responses (221 ± 4 μm), but response latency was significantly shorter with photovoltaic stimulation. Both visual and photovoltaic receptive fields had an opposing center-surround structure. In the healthy retina, ON RGCs had photovoltaic OFF responses, and vice versa. This reversal is consistent with depolarization of photoreceptors by electrical pulses, as opposed to their hyperpolarization under increasing light, although alternative mechanisms cannot be excluded. In degenerate retina, both ON and OFF photovoltaic responses were observed, but in the absence of visual responses, it is not clear what functional RGC types they correspond to. Degenerate retina maintained the antagonistic center-surround organization of receptive fields. These fast and spatially localized network-mediated ON and OFF responses to subretinal stimulation via photovoltaic pixels with local return electrodes raise confidence in the possibility of providing more functional prosthetic vision. NEW & NOTEWORTHY Retinal prostheses currently in clinical use have struggled to deliver visual information at naturalistic frequencies, resulting in discontinuous percepts. We

Photovoltaic Array Condition Monitoring Based on Online Regression of Performance Model

DEFF Research Database (Denmark)

Spataru, Sergiu; Sera, Dezso; Kerekes, Tamas

2013-01-01

regression modeling, from PV array production, plane-of-array irradiance, and module temperature measurements, acquired during an initial learning phase of the system. After the model has been parameterized automatically, the condition monitoring system enters the normal operation phase, where...

MATLAB Simulation of Photovoltaic and Photovoltaic/Thermal Systems Performance

Science.gov (United States)

Nasir, Farah H. M.; Husaini, Yusnira

2018-03-01

The efficiency of the photovoltaic reduces when the photovoltaic cell temperature increased due to solar irradiance. One solution is come up with the cooling system photovoltaic system. This combination is forming the photovoltaic-thermal (PV/T) system. Not only will it generate electricity also heat at the same time. The aim of this research is to focus on the modeling and simulation of photovoltaic (PV) and photovoltaic-thermal (PV/T) electrical performance by using single-diode equivalent circuit model. Both PV and PV/T models are developed in Matlab/Simulink. By providing the cooling system in PV/T, the efficiency of the system can be increased by decreasing the PV cell temperature. The maximum thermal, electrical and total efficiency values of PV/T in the present research are 35.18%, 15.56% and 50.74% at solar irradiance of 400 W/m2, mass flow rate of 0.05kgs-1 and inlet temperature of 25 °C respectively has been obtained. The photovoltaic-thermal shows that the higher efficiency performance compared to the photovoltaic system.

Advanced Solar Cell and Array Technology for NASA Deep Space Missions

Science.gov (United States)

Piszczor, Michael; Benson, Scott; Scheiman, David; Finacannon, Homer; Oleson, Steve; Landis, Geoffrey

2008-01-01

A recent study by the NASA Glenn Research Center assessed the feasibility of using photovoltaics (PV) to power spacecraft for outer planetary, deep space missions. While the majority of spacecraft have relied on photovoltaics for primary power, the drastic reduction in solar intensity as the spacecraft moves farther from the sun has either limited the power available (severely curtailing scientific operations) or necessitated the use of nuclear systems. A desire by NASA and the scientific community to explore various bodies in the outer solar system and conduct "long-term" operations using using smaller, "lower-cost" spacecraft has renewed interest in exploring the feasibility of using photovoltaics for to Jupiter, Saturn and beyond. With recent advances in solar cell performance and continuing development in lightweight, high power solar array technology, the study determined that photovoltaics is indeed a viable option for many of these missions.

Preprint Traffic Management and Forecasting System Based on 3D GIS

OpenAIRE

Li, Xiaoming; Lv, Zhihan; Hu, Jinxing; Zhang, Baoyun; Yin, Ling; Zhong, Chen; Wang, Weixi; Feng, Shengzhong

2015-01-01

This is the preprint version of our paper on 2015 15th IEEE/ACM International Symposium on Cluster, Cloud and Grid Computing (CCGrid). This paper takes Shenzhen Futian comprehensive transportation junction as the case, and makes use of continuous multiple real-time dynamic traffic information to carry out monitoring and analysis on spatial and temporal distribution of passenger flow under different means of transportation and service capacity of junction from multi-dimensional space-time pers...

Intermediate photovoltaic system application experiment operational performance executive summary. Volume 4. For Beverly High School, Beverly, MA

Energy Technology Data Exchange (ETDEWEB)

1982-02-01

Performance data are given for a 100 kW grid-connected flat panel photovoltaic power supply at a Massachusetts high school for the month of January, 1982. Data given include daily and monthly electrical energy produced, daily and monthly plane-of-array solar energy incident, array efficiency, power conditioner efficiency, system efficiency, capacity factor, and average plane-of-array insolation. Also included are the data acquisition mode and recording interval plot and two site event report summaries involving the data acquisition system. (LEW)

Report of an exploratory study: Safety and liability considerations for photovoltaic modules/panels

Science.gov (United States)

Weinstein, A. S.; Meeker, D. G.

1981-01-01

An overview of legal issues as they apply to design, manufacture and use of photovoltaic module/array devices is provided and a methodology is suggested for use of the design stage of these products to minimize or eliminate perceived hazards. Questions are posed to stimulate consideration of this area.

Stochastic control of smart home energy management with plug-in electric vehicle battery energy storage and photovoltaic array

Science.gov (United States)

Wu, Xiaohua; Hu, Xiaosong; Moura, Scott; Yin, Xiaofeng; Pickert, Volker

2016-11-01

Energy management strategies are instrumental in the performance and economy of smart homes integrating renewable energy and energy storage. This article focuses on stochastic energy management of a smart home with PEV (plug-in electric vehicle) energy storage and photovoltaic (PV) array. It is motivated by the challenges associated with sustainable energy supplies and the local energy storage opportunity provided by vehicle electrification. This paper seeks to minimize a consumer's energy charges under a time-of-use tariff, while satisfying home power demand and PEV charging requirements, and accommodating the variability of solar power. First, the random-variable models are developed, including Markov Chain model of PEV mobility, as well as predictive models of home power demand and PV power supply. Second, a stochastic optimal control problem is mathematically formulated for managing the power flow among energy sources in the smart home. Finally, based on time-varying electricity price, we systematically examine the performance of the proposed control strategy. As a result, the electric cost is 493.6% less for a Tesla Model S with optimal stochastic dynamic programming (SDP) control relative to the no optimal control case, and it is by 175.89% for a Nissan Leaf.

DOE LeRC photovoltaic systems test facility

Science.gov (United States)

Cull, R. C.; Forestieri, A. F.

1978-01-01

The facility was designed and built and is being operated as a national facility to serve the needs of the entire DOE National Photovoltaic Program. The object of the facility is to provide a place where photovoltaic systems may be assembled and electrically configured, without specific physical configuration, for operation and testing to evaluate their performance and characteristics. The facility as a breadboard system allows investigation of operational characteristics and checkout of components, subsystems and systems before they are mounted in field experiments or demonstrations. The facility as currently configured consist of 10 kW of solar arrays built from modules, two inverter test stations, a battery storage system, interface with local load and the utility grid, and instrumentation and control necessary to make a flexible operating facility. Expansion to 30 kW is planned for 1978. Test results and operating experience are summaried to show the variety of work that can be done with this facility.

An active cooling system for photovoltaic modules

International Nuclear Information System (INIS)

Teo, H.G.; Lee, P.S.; Hawlader, M.N.A.

2012-01-01

The electrical efficiency of photovoltaic (PV) cell is adversely affected by the significant increase of cell operating temperature during absorption of solar radiation. A hybrid photovoltaic/thermal (PV/T) solar system was designed, fabricated and experimentally investigated in this work. To actively cool the PV cells, a parallel array of ducts with inlet/outlet manifold designed for uniform airflow distribution was attached to the back of the PV panel. Experiments were performed with and without active cooling. A linear trend between the efficiency and temperature was found. Without active cooling, the temperature of the module was high and solar cells can only achieve an efficiency of 8–9%. However, when the module was operated under active cooling condition, the temperature dropped significantly leading to an increase in efficiency of solar cells to between 12% and 14%. A heat transfer simulation model was developed to compare to the actual temperature profile of PV module and good agreement between the simulation and experimental results is obtained.

Thin Film Photovoltaic Partnership Project | Photovoltaic Research | NREL

Science.gov (United States)

Thin Film Photovoltaic Partnership Project Thin Film Photovoltaic Partnership Project NREL's Thin Film Photovoltaic (PV) Partnership Project led R&D on emerging thin-film solar technologies in the United States from 1994 to 2009. The project made many advances in thin-film PV technologies that allowed

The photovoltaic industry is expanding under the sun; La filiere photovoltaique se dilate au soleil

Energy Technology Data Exchange (ETDEWEB)

Remoue, A

2010-03-15

From silicon to the manufacturing of solar cell arrays, professionals of the photovoltaic industry try to master the entire production line. A recent guidebook, published by the French syndicate of renewable energies lists 150 manufacturing and subcontracting companies in France. In 2009, the solar cell arrays installed in France represented 250 MWc of power, to be compared to 105 MWc in 2008. The production capacity should reach 331 MWc in 2010. (J.S.)

Energy Storage Publications | Transportation Research | NREL

Science.gov (United States)

, California. 23 pp.; NREL Report No. PR-5400-60290. Optimal Sizing of Energy Storage and Photovoltaic Power (11) 2017 pp. 1095-1118. Life Prediction Model for Grid-Connected Li-ion Battery Energy Storage System Prediction Model for Grid-Connected Li-ion Battery Energy Storage System - Preprint Paper Source: Smith

Design of a holographic micro-scale spectrum-splitting photovoltaic system

Science.gov (United States)

Wu, Yuechen; Vorndran, Shelby; Ayala Pelaez, Silvana; Russo, Juan M.; Kostuk, Raymond K.

2015-09-01

Micro-scale PV technology combines the high conversion efficiency of concentrated photovoltaics (CPV) with the low costs and the simple form of flat panel PV. Some of the benefits of micro-scale PV include: reduced semiconductor material usage; improved heat rejection capacity; and more versatile PV cell interconnect configurations. Spectrumsplitting is also a beneficial technique to increase the efficiency and reduce the cost of photovoltaic systems. It spatially separates the incident solar spectrum into spectral components and directs them to PV cells with matching bandgaps. This approach avoids the current and lattice matching problems that exist in tandem multi-junction systems. In this paper, we applied the ideas of spectrum-splitting in a micro-scale PV system, and demonstrated a holographic micro-scale spectrum-splitting photovoltaic system. This system consists of a volume transmission hologram in combination with a micro-lens array. An analysis methodology was developed to design the system and determine the performance of the resulting system. The spatial characteristics of the dispersed spectrum, the overall system conversion efficiency, and the improvement over best bandgap will be discussed.

Determination of hot-spot susceptibility of multistring photovoltaic modules in a central-station application

Science.gov (United States)

Gonzalez, C. C.; Weaver, R. W.; Ross, R. G., Jr.; Spencer, R.; Arnett, J. C.

1984-01-01

Part of the effort of the Jet Propulsion Laboratory (JPL) Flat-Plate Solar Array Project (FSA) includes a program to improve module and array reliability. A collaborative activity with industry dealing with the problem of hot-spot heating due to the shadowing of photovoltaic cells in modules and arrays containing several paralleled cell strings is described. The use of multiparallel strings in large central-station arrays introduces the likelihood of unequal current sharing and increased heating levels. Test results that relate power dissipated, current imbalance, cross-strapping frequency, and shadow configuration to hot-spot heating levels are presented. Recommendations for circuit design configurations appropriate to central-station applications that reduce the risk of hot-spot problems are offered. Guidelines are provided for developing hot-spot tests for arrays when current imbalance is a threat.

Analysis of batteries for use in photovoltaic systems. Final report

Energy Technology Data Exchange (ETDEWEB)

Podder, A; Kapner, M

1981-02-01

An evaluation of 11 types of secondary batteries for energy storage in photovoltaic electric power systems is given. The evaluation was based on six specific application scenarios which were selected to represent the diverse requirements of various photovoltaic systems. Electrical load characteristics and solar insulation data were first obtained for each application scenario. A computer-based simulation program, SOLSIM, was then developed to determine optimal sizes for battery, solar array, and power conditioning systems. Projected service lives and battery costs were used to estimate life-cycle costs for each candidate battery type. The evaluation considered battery life-cycle cost, safety and health effects associated with battery operation, and reliability/maintainability. The 11 battery types were: lead-acid, nickel-zinc, nickel-iron, nickel-hydrogen, lithium-iron sulfide, calcium-iron sulfide, sodium-sulfur, zinc-chlorine, zinc-bromine, Redox, and zinc-ferricyanide. The six application scenarios were: (1) a single-family house in Denver, Colorado (photovoltaic system connected to the utility line); (2) a remote village in equatorial Africa (stand-alone power system); (3) a dairy farm in Howard County, Maryland (onsite generator for backup power); (4) a 50,000 square foot office building in Washington, DC (onsite generator backup); (5) a community in central Arizona with a population of 10,000 (battery to be used for dedicated energy storage for a utility grid-connected photovoltaic power plant); and (6) a military field telephone office with a constant 300 W load (trailer-mounted auxiliary generator backup). Recommendations for a research and development program on battery energy storage for photovoltaic applications are given, and a discussion of electrical interfacing problems for utility line-connected photovoltaic power systems is included. (WHK)

Mission-Enabling Photovoltaic Flexible Blanket Solar Array with SNC/SJ Surface Mount Technology, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Deployable Space Systems, Inc. (DSS) in collaboration with Sierra Nevada Corporation (SNC) has developed a modular multi-junction photovoltaic flexible blanket...

Metastable Electrical Characteristics of Polycrystalline Thin-Film Photovoltaic Modules upon Exposure and Stabilization: Preprint

Energy Technology Data Exchange (ETDEWEB)

Deline, C. A.; del Cueto, J. A.; Albin, D. S.; Rummel, S. R.

2011-09-01

The significant features of a series of stabilization experiments conducted at the National Renewable Energy Laboratory (NREL) between May 2009 and the present are reported. These experiments evaluated a procedure to stabilize the measured performance of thin-film polycrystalline cadmium telluride (CdTe) and copper indium gallium diselenide (CIGS) thin-film photovoltaic (PV) modules. The current-voltage (I-V) characteristics of CdTe and CIGS thin-film PV devices and modules exhibit transitory changes in electrical performance after thermal exposure in the dark and/or bias and light exposures. We present the results of our case studies of module performance versus exposure: light-soaked at 65 degrees C; exposed in the dark under forward bias at 65 degrees C; and, finally, longer-term outdoor exposure. We find that stabilization can be achieved to varying degrees using either light-soaking or dark bias methods and that the existing IEC 61646 light-soaking interval may be appropriate for CdTe and CIGS modules with one caveat: it is likely that at least three exposure intervals are required for stabilization.

Electrocoagulation of a synthetic textile effluent powered by photovoltaic energy without batteries: Direct connection behaviour

Energy Technology Data Exchange (ETDEWEB)

Valero, David; Ortiz, Juan M.; Exposito, Eduardo; Montiel, Vicente; Aldaz, Antonio [Grupo de Electroquimica Aplicada y Electrocatalisis, Departamento de Quimica Fisica, Instituto Universitario de Electroquimica, Universidad de Alicante, Ap 99, Alicante 03080 (Spain)

2008-03-15

The feasibility of the use of an electrocoagulation system (EC) directly powered by a photovoltaic (PV) array has been demonstrated. The model pollutant used was a reactive textile dye Remazol Red RB 133. It has been proved that PV array configuration is a factor of great influence on the use of the generated power. The optimum PV array configuration must be reshaped depending on the instantaneous solar irradiation. A useful and effective methodology to adjust the EC-PV system operation conditions depending on solar irradiation has been proposed. The current flow ratio, J{sub v}, is established as the control parameter. (author)

A New Technique for Tracking the Global Maximum Power Point of PV Arrays Operating Under Partial-Shading Conditions

DEFF Research Database (Denmark)

Koutroulis, Eftichios; Blaabjerg, Frede

2012-01-01

The power-voltage characteristic of photovoltaic (PV) arrays operating under partial-shading conditions exhibits multiple local maximum power points (MPPs). In this paper, a new method to track the global MPP is presented, which is based on controlling a dc/dc converter connected at the PV array...

Modeling and Design of MPPT Controller Using Stepped P&O Algorithm in Solar Photovoltaic System

OpenAIRE

R. Prakash; B. Meenakshipriya; R. Kumaravelan

2014-01-01

This paper presents modeling and simulation of Grid Connected Photovoltaic (PV) system by using improved mathematical model. The model is used to study different parameter variations and effects on the PV array including operating temperature and solar irradiation level. In this paper stepped P&O algorithm is proposed for MPPT control. This algorithm will identify the suitable duty ratio in which the DC-DC converter should be operated to maximize the power output. Photo voltaic array with pro...

Numerical simulation of crosstalk in reduced pitch HgCdTe photon-trapping structure pixel arrays.

Science.gov (United States)

Schuster, Jonathan; Bellotti, Enrico

2013-06-17

We have investigated crosstalk in HgCdTe photovoltaic pixel arrays employing a photon trapping (PT) structure realized with a periodic array of pillars intended to provide broadband operation. We have found that, compared to non-PT pixel arrays with similar geometry, the array employing the PT structure has a slightly higher optical crosstalk. However, when the total crosstalk is evaluated, the presence of the PT region drastically reduces the total crosstalk; making the use of the PT structure not only useful to obtain broadband operation, but also desirable for reducing crosstalk in small pitch detector arrays.

Intermediate photovoltaic system application experiment operational performance report. Volume 6 for Beverly High School, Beverly, MA

Energy Technology Data Exchange (ETDEWEB)

1982-03-01

Performance data are given for the month of February, 1982 for a photovoltaic power supply at a Massachusetts high school. Data given include: monthly and daily electrical energy yield; monthly and daily insolation; monthly and daily array efficiency; energy production as a function of power level, voltage, cell temperature, and hour of day; insolation as a function of hour of the day; input, output and efficiency for each of two power conditioning units and for the total power conditioning system; energy supplied to the load by the photovoltaic system and by the grid; photovoltaic system efficiency; dollar value of the energy supplied by the photovoltaic system; capacity factor; daily photovoltaic energy to load; daily system availability and hours of daylight; heating and cooling degree days; hourly cell temperature, ambient temperature, wind speed, and insolation; average monthly wind speed; wind direction distribution; and daily data acquisition mode and recording interval plot. Also included are four site event report summaries, one involving hardware/maintenance for a power conditioning inverter, and the other three involving operations. (LEW)

Proceedings of the 12th Space Photovoltaic Research and Technology Conference (SPRAT 12)

Science.gov (United States)

1993-01-01

The Twelfth Space Photovoltaic Research and Technology conference was held at the NASA Lewis Research Center from 20 to 22 Oct. 1992. The papers and workshops presented in this volume report substantial progress in a variety of areas in space photovoltaics. Topics covered include: high efficiency GaAs and InP solar cells, GaAs/Ge cells as commercial items, flexible amorphous and thin film solar cells (in the early stages of pilot production), high efficiency multiple bandgap cells, laser power converters, solar cell and array technology, heteroepitaxial cells, betavoltaic energy conversion, and space radiation effects in InP cells. Space flight data on a variety of cells were also presented.

Photovoltaic module and laminate

Science.gov (United States)

Bunea, Gabriela E.; Kim, Sung Dug; Kavulak, David F.J.

2018-04-10

A photovoltaic module is disclosed. The photovoltaic module has a first side directed toward the sun during normal operation and a second, lower side. The photovoltaic module comprises a perimeter frame and a photovoltaic laminate at least partially enclosed by and supported by the perimeter frame. The photovoltaic laminate comprises a transparent cover layer positioned toward the first side of the photovoltaic module, an upper encapsulant layer beneath and adhering to the cover layer, a plurality of photovoltaic solar cells beneath the upper encapsulant layer, the photovoltaic solar cells electrically interconnected, a lower encapsulant layer beneath the plurality of photovoltaic solar cells, the upper and lower encapsulant layers enclosing the plurality of photovoltaic solar cells, and a homogenous rear environmental protection layer, the rear environmental protection layer adhering to the lower encapsulant layer, the rear environmental protection layer exposed to the ambient environment on the second side of the photovoltaic module.

Note on: Considering the Case for Biodiversity Cycles: Reexamining the Evidence for Periodicity in the Fossil Record, by Lieberman and Melott, arXiv preprint 0704.2896

OpenAIRE

Omerbashich, M.

2007-01-01

Lieberman and Melott built their recent arXiv preprint 0704.2896 on my published paper and (a preprint of) a subsequent comment by Liebermans associate Cornette. But had this group waited for the Cornette comment to actually appear in print together with the expected Reply, they would have learned that his comment exposes Cornettes confusion that likely was due to journal misprint of my figure. Thus 0704.2896 is baseless. Despite receiving the extended Reply with Errata, these authors still f...

Analytical Modelling and Simulation of Photovoltaic Panels and Arrays

Directory of Open Access Journals (Sweden)

H. Bourdoucen

2007-12-01

Full Text Available In this paper, an analytical model for PV panels and arrays based on extracted physical parameters of solar cells is developed. The proposed model has the advantage of simplifying mathematical modelling for different configurations of cells and panels without losing efficiency of PV system operation. The effects of external parameters, mainly temperature and solar irradiance have been considered in the modelling. Due to their critical effects on the operation of the panel, effects of series and shunt resistances were also studied. The developed analytical model has been easily implemented, simulated and validated using both Spice and Matlab packages for different series and parallel configurations of cells and panels. The results obtained with these two programs are in total agreement, which make the proposed model very useful for researchers and designers for quick and accurate sizing of PV panels and arrays.

Competition - In front of China, the photovoltaic sector organizes itself

International Nuclear Information System (INIS)

Chandes, C.

2012-01-01

Urged by the French President, EDF has taken Photowatt over. Photowatt used to be a leader in the fabrication of photovoltaic arrays. In other countries like Germany or the United States, measures are also implemented to face the competition with China in this sector. In Germany, banks are investing to save companies like Q-Cell. In the United States, manufacturers are asking their government to build up trade barriers

An analytical method to determine the optimal size of a photovoltaic plant

Energy Technology Data Exchange (ETDEWEB)

Barra, L; Catalanotti, S; Fontana, F; Lavorante, F

1984-01-01

In this paper, a simplified method for the optimal sizing of a photovoltaic system is presented. The results have been obtained for Italian meteorological data, but the methodology can be applied to any geographical area. The system studied is composed of a photovoltaic array, power tracker, battery storage, inverter and load. Computer simulation was used to obtain the performance of this system for many values of field area, battery storage value, solar flux and load by keeping constant the efficiencies. A simple fit was used to achieve a formula relating the system variables to the performance. Finally, the formulae for the optimal values of the field area and the battery storage value are shown.

Intermediate photovoltaic system application experiment operational performance. Volume 5, for Beverly High School, Beverly, MA. Executive summary

Energy Technology Data Exchange (ETDEWEB)

None,

1982-03-01

Performance data are given for a grid-connected, 100 kW, flat panel photovoltaic power system at a Massachusetts high school for the month of February 1982. Data include daily and monthly electrical energy produced, daily and monthly plane-of-array incident solar energy, array efficiency, power conditioner efficiency, system efficiency, capacity factor, and monthly average insolation. Also included is the data acquisition mode and recording interval plot. (LEW)

Retrieval of Mir Solar Array

Science.gov (United States)

Rutledge, Sharon K.; deGroh, Kim K.

1999-01-01

A Russian solar array panel removed in November 1997 from the non-articulating photovoltaic array on the Mir core module was returned to Earth on STS-89 in January 1998. The panel had been exposed to low Earth orbit (LEO) for 10 years prior to retrieval. The retrieval provided a unique opportunity to study the effects of the LEO environment on a functional solar array. To take advantage of this opportunity, a team composed of members from RSC-Energia (Russia), the Boeing Company, and the following NASA Centers--Johnson Space Center, Kennedy Space Center, Langley Research Center, Marshall Space Flight Center, and Lewis Research Center--was put together to analyze the array. After post-retrieval inspections at the Spacehab Facility at Kennedy in Florida, the array was shipped to Lewis in Cleveland for electrical performance tests, closeup photodocumentation, and removal of selected solar cells and blanket material. With approval from RSC-Energia, five cell pairs and their accompanying blanket and mesh material, and samples of painted handrail materials were selected for removal on the basis of their ability to provide degradation information. Sites were selected that provided different sizes and shapes of micrometeoroid impacts and different levels of surface contamination. These materials were then distributed among the team for round robin testing.

Physics of Quantum Structures in Photovoltaic Devices

Science.gov (United States)

Raffaelle, Ryne P.; Andersen, John D.

2005-01-01

There has been considerable activity recently regarding the possibilities of using various nanostructures and nanomaterials to improve photovoltaic conversion of solar energy. Recent theoretical results indicate that dramatic improvements in device efficiency may be attainable through the use of three-dimensional arrays of zero-dimensional conductors (i.e., quantum dots) in an ordinary p-i-n solar cell structure. Quantum dots and other nanostructured materials may also prove to have some benefits in terms of temperature coefficients and radiation degradation associated with space solar cells. Two-dimensional semiconductor superlattices have already demonstrated some advantages in this regard. It has also recently been demonstrated that semiconducting quantum dots can also be used to improve conversion efficiencies in polymeric thin film solar cells. Improvement in thin film cells utilizing conjugated polymers has also be achieved through the use of one-dimensional quantum structures such as carbon nanotubes. It is believed that carbon nanotubes may contribute to both the disassociation as well as the carrier transport in the conjugated polymers used in certain thin film photovoltaic cells. In this paper we will review the underlying physics governing some of the new photovoltaic nanostructures being pursued, as well as the the current methods being employed to produce III-V, II-VI, and even chalcopyrite-based nanomaterials and nanostructures for solar cells.

A Study of Stress Distribution in Layered and Gradient Tribological Coatings (Preprint)

Science.gov (United States)

2006-11-01

FG) Ti/TiC coating design. On the top of the 440C stainless steel substrate, α-Ti is added as a bond layer with 50nm thickness to improve the... stainless steel substrate and the rigid spherical indenter was performed. Figure 5 (a) shows the normalized Hertzian point contact pressure distribution...AFRL-ML-WP-TP-2007-402 A STUDY OF STRESS DISTRIBUTION IN LAYERED AND GRADIENT TRIBOLOGICAL COATINGS (PREPRINT) Young Sup Kang, Shashi K

Optimal sizing method for stand-alone photovoltaic power systems

Energy Technology Data Exchange (ETDEWEB)

Groumpos, P P; Papageorgiou, G

1987-01-01

The total life-cycle cost of stand-alone photovoltaic (SAPV) power systems is mathematically formulated. A new optimal sizing algorithm for the solar array and battery capacity is developed. The optimum value of a balancing parameter, M, for the optimal sizing of SAPV system components is derived. The proposed optimal sizing algorithm is used in an illustrative example, where a more economical life-cycle cost has bene obtained. The question of cost versus reliability is briefly discussed.

Photovoltaic subsystem optimization and design tradeoff study. Final report

Energy Technology Data Exchange (ETDEWEB)

Stolte, W.J.

1982-03-01

Tradeoffs and subsystem choices are examined in photovoltaic array subfield design, power-conditioning sizing and selection, roof- and ground-mounted structure installation, energy loss, operating voltage, power conditioning cost, and subfield size. Line- and self-commutated power conditioning options are analyzed to determine the most cost-effective technology in the megawatt power range. Methods for reducing field installation of flat panels and roof mounting of intermediate load centers are discussed, including the cost of retrofit installations.

Photovoltaic module and interlocked stack of photovoltaic modules

Science.gov (United States)

Wares, Brian S.

2012-09-04

One embodiment relates to an arrangement of photovoltaic modules configured for transportation. The arrangement includes a plurality of photovoltaic modules, each photovoltaic module including a frame having at least a top member and a bottom member. A plurality of alignment features are included on the top member of each frame, and a plurality of alignment features are included on the bottom member of each frame. Adjacent photovoltaic modules are interlocked by the alignment features on the top member of a lower module fitting together with the alignment features on the bottom member of an upper module. Other embodiments, features and aspects are also disclosed.

Intermediate photovoltaic system application experiment operational performance report: Volume 5, for Beverly High School, Beverly, Mass.

Science.gov (United States)

1982-02-01

Performance data for the month of January, 1982 for a grid connected photovoltaic power supply in Massachusetts are presented. Data include: monthly and daily electrical energy produced; monthly and daily solar energy incident on the array; monthly and daily array efficiency; plots of energy produced as a function of power level, voltage, cell temperature and time of day; power conditioner input, output and efficiency for each of two individual units and for the total power conditioning system; photovoltaic system efficiency; capacity factor; PV system to load and grid to load energies and corresponding dollar values; daily energy supplies to the load by the PV system; daily PV system availability; monthly and hourly insolation; monthly and hourly temperature average; monthly and hourly wind speed; wind direction distribution; average heating and cooling degree days; number of freeze/thaw cycles; and the data acquisition mode and recording interval plot.

FY 2000 report on the results of the development of technology for commercialization of the photovoltaic power system - R and D of evaluation technology of the photovoltaic power system. R and D of the system evaluation technology; 2000 nendo New sunshine keikaku seika hokokusho. Taiyoko hatsuden system jitsuyoka gijutsu kaihatsu - Taiyoko hatsuden system hyoka gijutsu no kenkyu kaihatsu - System hyoka gijutsu no kenkyu kaihatsu

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

Based on the evaluation method for the performance prediction system of the standard photovoltaic power system, the R and D were conducted of the system generation output prediction technology which is general-purpose, simplified and applicable to various kinds of photovoltaic power system for residential use, and the FY 2000 results were summed up. In this fiscal year, the photovoltaic power system for residential use was increasingly installed at 15 places, and 100 sites in total were made database and analyzed. As to the development of simulation technology, technology of calculation was established such as the simulation of multi-plane array composition and correction of multi-plane array incidence. Further, technical information on system trouble and knowledge/information/proposal for reducing power generation loss were arranged by design parameter. Using the data on solar radiation/power loss at sites of residential use photovoltaic power systems installed in the Kanto area, value analysis of the capacity of wide area facilities of the photovoltaic power system was made by the statistical method. This study was compiled into the revised edition of design manual. (NEDO)

Photovoltaic demonstration projects

Energy Technology Data Exchange (ETDEWEB)

Gillett, W B; Hacker, R J; Kaut, W [eds.

1991-01-01

This book, the proceedings of the fourth PV-Contractors' Meeting organized by the Commission of the European Communities, Directorate-General for Energy, held at Brussels on 21 and 22 November 1989, provides an overview of the photovoltaic demonstration projects which have been supported in the framework of the Energy Demonstration Program since 1983. It includes reports by each of the contractors who submitted proposals in 1983, 1984, 1985 and 1986, describing progress with their projects. Summaries of the discussions held at the meeting, which included contractors whose projects were submitted in 1987, are also presented. The different technologies which are being demonstrated concern the modules, the cabling of the array, structure design, storage strategy and power conditioning. The various applications include desalination, communications, dairy farms, water pumping, and warning systems. Papers have been processed separately for inclusion on the data base.

Preprints na comunicação científica da Física de Altas Energias: análise das submissões no repositório arXiv (2010-2015

Directory of Open Access Journals (Sweden)

Gonzalo Rubén Alvarez

Full Text Available RESUMO A circulação de preprints na Física de Altas Energias (FAE remonta a mais de meio século, tendo como objetivos principais acelerar o processo de comunicação científica entre os pares e estimular o acesso livre à literatura especializada da área. O artigo analisa o conjunto de preprints submetidos às diferentes categorias FAE do repositório temático especializado arXiv no período 2010-2015 que foram posteriormente publicados em revistas peer review. Os indicadores bibliométricos demonstram a potencialidade dos preprints como canal precursor de difusão de resultados científicos visto que 70% das submissões foram em seguida absorvidas pelas principais revistas da FAE. Conclui que o êxito alcançado pelas iniciativas Open Access arXiv e INSPIRE-HEP favoreceu o intercâmbio de informações e conhecimentos entre os pesquisadores. O modelo proposto pela FAE pode incentivar cientistas de áreas com características similares a instalarem repositórios e bancos de dados de preprints para suas disciplinas com o intuito de fortalecer a comunicação das descobertas científicas.

Environmental testing of terrestrial flat plate photovoltaic modules

Science.gov (United States)

Hoffman, A.; Griffith, J.

1979-01-01

The Low-Cost Solar Array (LSA) Project at the Jet Propulsion Laboratory has as one objective: the development and implementation of environmental tests for flat plate photovoltaic modules as part of the Department of Energy's terrestrial photovoltaic program. Modules procured under this program have been subjected to a variety of laboratory tests intended to simulate service environments, and the results of these tests have been compared to available data from actual field service. This comparison indicates that certain tests (notably temperature cycling, humidity cycling, and cyclic pressure loading) are effective indicators of some forms of field failures. Other tests have yielded results useful in formulating module design guidelines. Not all effects noted in field service have been successfully reproduced in the laboratory, however, and work is continuing in order to improve the value of the test program as a tool for evaluating module design and workmanship. This paper contains a review of these ongoing efforts and an assessment of significant test results to date.

A photovoltaic module

DEFF Research Database (Denmark)

2013-01-01

The present invention relates to a photovoltaic module comprising a carrier substrate, said carrier substrate carrying a purely printed structure comprising printed positive and negative module terminals, a plurality of printed photovoltaic cell units each comprising one or more printed...... photovoltaic cells, wherein the plurality of printed photovoltaic cell units are electrically connected in series between the positive and the negative module terminals such that any two neighbouring photovoltaic cell units are electrically connected by a printed interconnecting electrical conductor....... The carrier substrate comprises a foil and the total thickness of the photovoltaic module is below 500 [mu]m. Moreover, the nominal voltage level between the positive and the negative terminals is at least 5 kV DC....

Photovoltaic device

Energy Technology Data Exchange (ETDEWEB)

Reese, Jason A; Keenihan, James R; Gaston, Ryan S; Kauffmann, Keith L; Langmaid, Joseph A; Lopez, Leonardo; Maak, Kevin D; Mills, Michael E; Ramesh, Narayan; Teli, Samar R

2017-03-21

The present invention is premised upon an improved photovoltaic device ("PV device"), more particularly to an improved photovoltaic device with a multilayered photovoltaic cell assembly and a body portion joined at an interface region and including an intermediate layer, at least one interconnecting structural member, relieving feature, unique component geometry, or any combination thereof.

Photovoltaic device

Science.gov (United States)

Reese, Jason A.; Keenihan, James R.; Gaston, Ryan S.; Kauffmann, Keith L.; Langmaid, Joseph A.; Lopez, Leonardo C.; Maak, Kevin D.; Mills, Michael E.; Ramesh, Narayan; Teli, Samar R.

2015-06-02

The present invention is premised upon an improved photovoltaic device ("PV device"), more particularly to an improved photovoltaic device with a multilayered photovoltaic cell assembly and a body portion joined at an interface region and including an intermediate layer, at least one interconnecting structural member, relieving feature, unique component geometry, or any combination thereof.

The market of solar and photovoltaic energies. Grid parity, new support mechanisms, and innovations in financing modes: perspectives by 2018 and overview of actors

International Nuclear Information System (INIS)

2015-01-01

This study first proposes an analysis and a discussion of perspectives for the sector of solar and photovoltaic energies. It identifies the main determining factors of the sector activity, proposes an overview of the sector activity between 2006 and 2015 (evolution of determining factors, installed power, production of photovoltaic electricity, installations on private dwellings, electricity price, foreign trade of photovoltaic arrays, turnover for the solar thermal and photovoltaic sector), discusses perspectives by 2018 in terms of installed power, of turnover, and of opportunities and threats. The second part proposes a description of the sector context: analysis of structural brakes and drivers, overview of the world market, installed power and photovoltaic electricity production in Europe, and overview of the French context of photovoltaic solar energy (energy policy, commitment of public authorities, electricity purchase tariff, and competitiveness of photovoltaic electricity). The third part evokes highlights of the sector and discusses the offer evolution: emergence of new financing modes, technological innovations, diversification of activity, international activity of French actors, and takeovers and optimisation of organisations. The fourth part reports an analysis of the competition context: competition pressure on array manufacturers, pressure on solar plant operators, and analysis of substitutes to solar energy. The fifth part proposes an overview of the economic structure and existing competing forces of the sector in France, and provides sheets of data for the main French actors. The last part proposes economic and financial indicators to assess and compare the performance of 200 enterprises belonging to this sector

Grid-connected photovoltaic systems. Projecting, construction, sales - hints for expert technicians. 3. new rev. ed.; Netzgekoppelte Photovoltaikanlangen. Planung, Errichtung und Verkauf fuer den Handwerksprofi

Energy Technology Data Exchange (ETDEWEB)

Sandner, Thomas

2013-02-01

Photovoltaic conversion is one of the most efficient and also one of the fastest-growing sustainable technologies. The book starts by presenting the fundamentals of photovoltaic conversion and solar radiation and then proceeds to describe the components of grid-connected PV systems. Other issues of this book consider: On-site visit and selection of a suitable generator array; The Renewable Energy Law and the development of photovoltaic conversion in Germany; Business topics such as costs and prices, marketing, quality assurance; Internal use of solar power.

Design of a photovoltaic-hydrogen-fuel cell energy system

Energy Technology Data Exchange (ETDEWEB)

Lehman, P A; Chamberlin, C E [Humboldt State Univ., Arcata, CA (US). Dept. of Environmental Resources Engineering

1991-01-01

The design of a stand-alone renewable energy system using hydrogen (H{sub 2}) as the energy storage medium and a fuel cell as the regeneration technology is reported. The system being installed at the Humboldt State University Telonicher Marine Laboratory consists of a 9.2 kW photovoltaic (PV) array coupled to a high pressure, bipolar alkaline electrolyser. The array powers the Laboratory's air compressor system whenever possible; excess power is shunted to the electrolyser for hydrogen and oxygen (O{sub 2}) production. When the array cannot provide sufficient power, stored hydrogen and oxygen are furnished to a proton exchange membrane fuel cell which, smoothly and without interruption, supplies the load. In reporting the design, details of component selection, sizing, and integration, control system logic and implementation, and safety considerations are discussed. Plans for a monitoring network to chronicle system performance are presented, questions that will be addressed through the monitoring program are included, and the present status of the project is reported. (Author).

Design of photovoltaic array electrical system based on solar power generation%基于太阳能发电的光伏阵列电气系统设计

Institute of Scientific and Technical Information of China (English)

窦伟山; 王薇

2017-01-01

清洁能源的使用是未来社会发展的趋势.以光伏发电为研究模型,对实现太阳能的高效利用展开研究,提出了一种高效的光伏阵列,使太阳能发电系统的能源利用率得到了显著的提升.通过对太阳能发电的电气系统进行一次设计,提出了35 kV侧无功补偿装置,使得系统更加合理、有效.%The use of clean energy is the future trend of social development.Using the solar photovoltaic power generation as the research model,the efficient utilization of solar energy was researched.A kind of high efficient photovoltaic array was put forward,significantly improving the energy efficiency of solar power generation system.Through the design of solar power generation electrical system,the 35 kV side reactive power compensation device was put forward,making the system more reasonable and effective.

Environmental assessment and environmental impact of photovoltaic installations. Synthesis of the OFATE conference of 12 April 2016

International Nuclear Information System (INIS)

Eckardt, Nils; Schaefer, Oliver; Argenlieu, Philippe d'; Chaufaux, Emilie; Uhlig, Matthias; Durand, Yvonnick; Burgun, Francoise; Cacqueray, Philippe de; Harle d'Ophove, Armand; Guerrier, Pierre; Massiac, Jean-Christophe de; Fischer, Thomas

2016-09-01

This publication proposes a synthesis of contributions and the contributions of a conference organised by the French-German Office for Energy Transition (OFATE). The synthesis proposes an overview of the status and potential of photovoltaic energy in Europe, a discussion of eligible areas and support to photovoltaic in compliance with the protection of the environment in France and in Germany, and a discussion of innovating approaches aimed at reducing the ecological print of solar power production (technological advances in solar cell production, conciliation of solar electric power production with agriculture, livestock and protection of species, legal and environmental aspects of the processing of photovoltaic components). The conference was organised in sessions: support to photovoltaic from the ecological point of view (the untapped potential of solar in France and Germany, integration of the environmental assessment in photovoltaic bidding and rules for surface use for photovoltaic in the town planning code, debate on available surfaces, and on the compliance between photovoltaic development, the environment and agriculture), innovating approaches to reduce the ecological print in solar electricity production (the EuroPlas project for a new process of ecological production of solar cells, the European Ecolabel project for photovoltaic modules, farm and solar parks by Neoen, synergies between orientable solar arrays and plant cultivation, the PIESO project for a better ecological integration of ground-based power plants), and the recycling of photovoltaic components (debate on legal aspects and environmental aspects regarding their processing, keynote on the transposition of a European directive)

Photovoltaic-Pyroelectric Coupled Effect Induced Electricity for Self-Powered Photodetector System.

Science.gov (United States)

Ma, Nan; Zhang, Kewei; Yang, Ya

2017-12-01

Ferroelectric materials have demonstrated novel photovoltaic effect to scavenge solar energy. However, most of the ferroelectric materials with wide bandgaps (2.7-4 eV) suffer from low power conversion efficiency of less than 0.5% due to absorbing only 8-20% of solar spectrum. Instead of harvesting solar energy, these ferroelectric materials can be well suited for photodetector applications, especially for sensing near-UV irradiations. Here, a ferroelectric BaTiO 3 film-based photodetector is demonstrated that can be operated without using any external power source and a fast sensing of 405 nm light illumination is enabled. As compared with photovoltaic effect, both the responsivity and the specific detectivity of the photodetector can be dramatically enhanced by larger than 260% due to the light-induced photovoltaic-pyroelectric coupled effect. A self-powered photodetector array system can be utilized to achieve spatially resolved light intensity detection by recording the output voltage signals as a mapping figure. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Solar Array Sails: Possible Space Plasma Environmental Effects

Science.gov (United States)

Mackey, Willie R.

2005-01-01

An examination of the interactions between proposed "solar sail" propulsion systems with photovoltaic energy generation capabilities and the space plasma environments. Major areas of interactions ere: Acting from high voltage arrays, ram and wake effects, V and B current loops and EMI. Preliminary analysis indicates that arcing will be a major risk factor for voltages greater than 300V. Electron temperature enhancement in the wake will be produce noise that can be transmitted via the wake echo process. In addition, V and B induced potential will generate sheath voltages with potential tether like breakage effects in the thin film sails. Advocacy of further attention to these processes is emphasized so that plasma environmental mitigation will be instituted in photovoltaic sail design.

Photovoltaic power systems energy storage

International Nuclear Information System (INIS)

Buldini, P.L.

1991-01-01

Basically, the solar photovoltaic power system consists of: Array of solar panels; Charge/voltage stabilizer; Blocking diode and Storage device. The storage device is a very important part of the system due to the necessity to harmonize the inevitable time shift between energy supply and demand. As energy storage, different devices can be utilized, such as hydropumping, air or other gas compression, flywheel, superconducting magnet, hydrogen generation and so on, but actually secondary (rechargeable) electrochemical cells appear to be the best storage device, due to the direct use for recharge of the d.c. current provided by the solar panels, without any intermediate step of energy transformation and its consequent loss of efficiency

Organic photovoltaics

DEFF Research Database (Denmark)

Demming, Anna; Krebs, Frederik C; Chen, Hongzheng

2013-01-01

's supply, even at our increasingly ravenous rate of global energy consumption [1]. But it's not what you have got it's what you do with it. Hence the intense focus on photovoltaic research to find more efficient ways to harness energy from the Sun. Recently much of this research has centred on organic...... solar cells since they offer simple, low-cost, light-weight and large-area flexible photovoltaic structures. This issue with guest editors Frederik C Krebs and Hongzheng Chen focuses on some of the developments at the frontier of organic photovoltaic technology. Improving the power conversion efficiency...... of organic photovoltaic systems, while maintaining the inherent material, economic and fabrication benefits, has absorbed a great deal of research attention in recent years. Here significant progress has been made with reports now of organic photovoltaic devices with efficiencies of around 10%. Yet operating...

Photovoltaic barometer

International Nuclear Information System (INIS)

2014-01-01

The global solar photovoltaic market enjoyed a strong revival in 2013. Preliminary estimates put it in excess of 37 GWp, compared to 30 GWp in 2012 and 2011. The solar photovoltaic sector led the annual installed capacity ratings for renewable energies, taking worldwide capacity up to 137 GWp by the end of the year which means a 35% year-on-year increase. At global level the high growth markets - China, Japan and America - contrast sharply with the contracting European Union market. The strong recovery of the global photovoltaic market is due to the drop in module prices which in some zones has dropped below the conventional electricity price. In the E.U, in 2013 the photovoltaic electricity reached 80.2 TWh while the capacity connected during this year was 9922.2 MWp. Concerning the capacity connected in 2013 the 2 main contributors in Europe are Germany (3310.0 MWc) and Italy (1462.0 MWc). These 2 countries represent also 68% of the cumulated and connected capacity in Europe. All along the article various charts and tables give the figures of the photovoltaic capacity per inhabitant for each E.U country in 2013, the electricity production from photovoltaic power for each E.U country, and the main photovoltaic module manufacturers in 2013 worldwide reporting production and turnover

Can Integrated Micro-Optical Concentrator Technology Revolutionize Flat-Plate Photovoltaic Solar Energy Harvesting?

Science.gov (United States)

Haney, Michael W.

2015-12-01

The economies-of-scale and enhanced performance of integrated micro-technologies have repeatedly delivered disruptive market impact. Examples range from microelectronics to displays to lighting. However, integrated micro-scale technologies have yet to be applied in a transformational way to solar photovoltaic panels. The recently announced Micro-scale Optimized Solar-cell Arrays with Integrated Concentration (MOSAIC) program aims to create a new paradigm in solar photovoltaic panel technology based on the incorporation of micro-concentrating photo-voltaic (μ-CPV) cells. As depicted in Figure 1, MOSAIC will integrate arrays of micro-optical concentrating elements and micro-scale PV elements to achieve the same aggregated collection area and high conversion efficiency of a conventional (i.e., macro-scale) CPV approach, but with the low profile and mass, and hopefully cost, of a conventional non-concentrated PV panel. The reduced size and weight, and enhanced wiring complexity, of the MOSAIC approach provide the opportunity to access the high-performance/low-cost region between the conventional CPV and flat-plate (1-sun) PV domains shown in Figure 2. Accessing this portion of the graph in Figure 2 will expand the geographic and market reach of flat-plate PV. This talk reviews the motivation and goals for the MOSAIC program. The diversity of the technical approaches to micro-concentration, embedded solar tracking, and hybrid direct/diffuse solar resource collection found in the MOSAIC portfolio of projects will also be highlighted.

Law guide for photovoltaic installations: Array installation; Connecting the grid; Financing; The new legal regime implemented in 2011; Is green taxing still so green?; Which judge will bring the light?: Reactions of actors

International Nuclear Information System (INIS)

Ferracci, Vanina; Vandervorst, Alain; Tixier, Jean-Luc; Barthelemy, Christophe; Cloche-Dubois, Celine; Tenailleau, Francois; Rubio, Aurore-Emmanuelle; Pechamat, Olivier; Gandet, Stephanie; Deharbe, David; Rousset, Alain; Boedec, Morgan; Joffre, Andre; Blosseville, Thomas; Meunier, Stephane; Maincent, Guillaume

2011-01-01

The authors discuss legal issues and aspects regarding photovoltaic installations in France: the array installation (constraints related to urban planning: rules, authorizations and competencies when setting up on the ground or on buildings, urban taxes, estate issues), the connection to the grid, the financing (electricity prices, partnership contract), the new legal regime implemented in 2011, the question whether green taxing is still sufficiently attractive, the dispute about the mandatory purchase mechanism, and the attitude of the different actors (notably local communities, and industries) in front of the decrease of purchase prices

HgCdTe e-avalanche photodiode detector arrays

Directory of Open Access Journals (Sweden)

Anand Singh

2015-08-01

Full Text Available Initial results on the MWIR e-APD detector arrays with 30 μm pitch fabricated on LPE grown compositionally graded p-HgCdTe epilayers are presented. High dynamic resistance times active area (R0A product 2 × 106 Ω-cm2, low dark current density 4 nA/cm2 and high gain 5500 at -8 V were achieved in the n+-υ-p+ HgCdTe e-APD at 80 K. LPE based HgCdTe e-APD development makes this technology amenable for adoption in the foundries established for the conventional HgCdTe photovoltaic detector arrays without any additional investment.

Photovoltaic device

Science.gov (United States)

Reese, Jason A.; Keenihan, James R.; Gaston, Ryan S.; Kauffmann, Keith L.; Langmaid, Joseph A.; Lopez, Leonardo C.; Maak, Kevin D.; Mills, Michael E.; Ramesh, Narayan; Teli, Samar R.

2015-09-01

The present invention is premised upon an improved photovoltaic device ("PV device"), more particularly to an improved photovoltaic device (10) with a multilayered photovoltaic cell assembly (100) and a body portion (200) joined at an interface region (410) and including an intermediate layer (500), at least one interconnecting structural member (1500), relieving feature (2500), unique component geometry, or any combination thereof.

A review on sizing methodologies of photovoltaic array and storage battery in a standalone photovoltaic system

International Nuclear Information System (INIS)

Khatib, Tamer; Ibrahim, Ibrahim A.; Mohamed, Azah

2016-01-01

Highlights: • We review the current methods for sizing standalone PV systems. • We review the current criteria adapted in sizing standalone PV systems. • We review current method for sizing battery in standalone PV systems. - Abstract: The reliance of future energy demand on standalone PV system is based on its payback period and particular electrical grid parity prices. This highlights the importance for optimum and applicable methods for sizing these systems. Moreover, the designers are being more sensitive toward simple and reliable sizing models for standalone PV system. This paper proposes a review on important knowledge that needs to be taken into account while designing and implementing standalone PV systems. Such a knowledge includes configurations of standalone photovoltaic system, evaluation criteria for unit sizing, sizing methodologies. Moreover, this review provides highlights on challenges and limitations of standalone PV system size optimization techniques.

Degradation of Solar Array Components in a Combined UV/VUV High Temperature Test Environment

Directory of Open Access Journals (Sweden)

Nömayr Christel

2017-01-01

A design verification test under UV/VUV conditions of sun exposed materials and technologies on component level is presented which forms part of the overall verification and qualification of the solar array design of the MTM and MPO. The test concentrates on the self-contamination aspects and the resulting performance losses of the solar array under high intensity and elevated temperature environment representative for the photovoltaic assembly (PVA.

Research and development of evaluation system for photovoltaic power generation system. Research and development on evaluation technology of photovoltaic power generating systems; Taiyoko hatsuden system hyoka gijutsu no kenkyu kaihatsu. System hyoka gijutsu no kenkyu kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Tatsuta, M [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

1994-12-01

This paper reports the study results on R and D of evaluation technology for photovoltaic power generating systems in fiscal 1994. (1) On preparation of test facility and measuring instrument, the pyrheliometer with a photovoltaic device as sensor was developed. (2) On collection and analysis of data, operation data of interconnection system, stand alone system, and water pump system were collected, and energy flow was analyzed. The following were also analyzed: time variation of a-Si solar cell modules, fluctuation correction factor of spectrum response, that of nonlinear response of crystalline solar cells, effect of solar radiation intensity and wind velocity on temperature rise of modules, and correction factor of DC circuit losses. (3) On on-site measurement technology, the array output measuring instrument was developed on the basis of capacitor charge system. (4) On simulation technology, simulation analyses of energy flow, optimum capacity of interconnection systems, correction factor of solar radiation, and capacity of array storage batteries were conducted. 3 figs., 6 tabs.

Research on Experiment of Islanding Protection Device of Grid-connected Photovoltaic System Based on RTDS

Science.gov (United States)

Zhou, Ning; Yang, Jia; Cheng, Zheng; Chen, Bo; Su, Yong Chun; Shu, Zhan; Zou, Jin

2017-06-01

Solar photovoltaic power generation is the power generation using solar cell module converting sunlight into DC electric energy. In the paper an equivalent model of solar photovoltaic power generation system is built in RTDS. The main circuit structure of the two-stage PV grid-connected system consists of the DC-DC, DC-AC circuit. The MPPT (Maximum Power Point Tracking) control of the PV array is controlled by adjusting the duty ratio of the DC-DC circuit. The proposed control strategy of constant voltage/constant reactive power (V/Q) control is successfully implemented grid-connected control of the inverter when grid-connected operation. The closed-loop experiment of islanding protection device of photovoltaic power plant on RTDS, verifies the correctness of the simulation model, and the experimental verification can be applied to this type of device.

The second section of Delphos photovoltaic plant

Energy Technology Data Exchange (ETDEWEB)

Barra, L; Li Causi, S; Calogero, D; Sarno, A

1989-03-01

The 300 kWp photovoltaic (PV) system that will constitute the second section of the Delphos plant is made up by three 100 kWp modular standard units (PLUG), parallel connected to the grid. In this paper, the PV array, the power conditioning unit and the overall architecture of the standard unit are described and the relevant differences with respect to the first Delphos section are discussed. It is explained how the use of modular standardized units allows a substantial reduction of construction, installation and operations costs. Finally, a short evaluation of the expected energy cost is presented.

Modeling, Design and Simulation of Stand-Alone Photovoltaic Power Systems with Battery Storage

Directory of Open Access Journals (Sweden)

Abd Essalam BADOUD

2013-06-01

Full Text Available Stand alone renewable energy based on photovoltaic systems accompanied with battery storage system are beginning to play an important role over the world to supply power to remote areas. The objective of the study reported in this paper is to elaborate and design a bond graphs model for sizing stand-alone domestic solar photovoltaic electricity systems and simulating the performance of the systems in a tropical climate. The systems modelled consist of an array of PV modules, a lead-acid battery, and a number of direct current appliances. This paper proposes the combination of lead acid battery system with a typical stand alone photovoltaic energy system under variable loads. The main activities of this work purpose to establish library graphical models for each individual component of standalone photovoltaic system. Control strategy has been considered to achieve permanent power supply to the load via photovoltaic/battery based on the power available from the sun. The complete model was simulated under two testing including sunny and cloudy conditions. Simulation of the system using Symbols software was performed and the results of simulation show the superior stable control system and high efficiency. These results have been contrasted with real measured data from a measurement campaign plant carried on electrical engineering laboratory of Grenoble using various interconnection schemes are presented.

A novel fabrication of MEH-PPV/Al:ZnO nanorod arrays based ordered bulk heterojunction hybrid solar cells

Energy Technology Data Exchange (ETDEWEB)

Malek, M.F., E-mail: firz_solarzelle@yahoo.com [NANO-ElecTronic Centre (NET), Faculty of Electrical Engineering, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor (Malaysia); Sahdan, M.Z.; Mamat, M.H.; Musa, M.Z. [NANO-ElecTronic Centre (NET), Faculty of Electrical Engineering, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor (Malaysia); Khusaimi, Z.; Husairi, S.S. [NANO-SciTech Centre (NST), Institute of Science (IOS), Universiti Teknologi MARA -UiTM, 40450 Shah Alam, Selangor (Malaysia); Md Sin, N.D. [NANO-ElecTronic Centre (NET), Faculty of Electrical Engineering, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor (Malaysia); Rusop, M. [NANO-ElecTronic Centre (NET), Faculty of Electrical Engineering, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor (Malaysia); NANO-SciTech Centre (NST), Institute of Science (IOS), Universiti Teknologi MARA - UiTM, 40450 Shah Alam, Selangor (Malaysia)

2013-06-15

Vertically aligned Al:ZnO nanorod arrays has been used as window layer in the fabrication of ordered bulk heterojuction hybrid solar cells. The utilization of the nanorod arrays will enhance the electron transport in vertical direction and also for light harvesting applications for high performance devices. The performance of this hybrid polymer/metal oxide photovoltaic devices based on MEH-PPV [poly(2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene)] and oriented Al:ZnO nanorod arrays is studied. The Al:ZnO nanorod arrays with a diameter of about 70–80 nm and thickness of approximately 500 nm were successfully grown on Al:ZnO-coated ITO substrate by sonicated sol–gel immersion technique. The photovoltaic performance of a short-circuit current density of 5.320 mA/cm{sup 2}, an open-circuit voltage of 195 mV and a fill factor of 27.71%, with a power conversion efficiency of about 0.287% under AM 1.5 illumination (100 mW/cm{sup 2}). To the best of our knowledge, preparation of aligned Al:ZnO nanorod arrays for this type of solar cell fabrication has not been reported by any research group.

Size-Prediction Analysis for Stand-Alone Photovoltaic System

International Nuclear Information System (INIS)

Erusiafe, N. E.; Chendo, M. A. C.

2002-01-01

The cost - effectiveness of photovoltaic (PV) generator depends, among others, on its ability to satisfy energy demand and the cost of achieving this. In this work a step - by - step procedure for predicting the size of the main components of a stand - alone PV system (array and storage) is presented. The results yield an expression which can he used lo determine the size of both components at optimum cost and desired reliability. The result from this work compare favourably with some earlier works in that, the system sizes shows some degree of agreement

The virtual library in action: Collaborative international control of high-energy physics pre-print

International Nuclear Information System (INIS)

Kreitz, P.A.; Addis, L.; Galic, H.; Johnson, T.

1996-02-01

This paper will discuss how control of the grey literature in high-energy physics pre-prints developed through a collaborative effort of librarians and physicists. It will highlight the critical steps in the development process and describe one model of a rapidly evolving virtual library for high-energy physics information. In conclusion, this paper will extend this physics model to other areas of grey literature management

Applying a Cerebellar Model Articulation Controller Neural Network to a Photovoltaic Power Generation System Fault Diagnosis

Directory of Open Access Journals (Sweden)

Kuei-Hsiang Chao

2013-01-01

Full Text Available This study employed a cerebellar model articulation controller (CMAC neural network to conduct fault diagnoses on photovoltaic power generation systems. We composed a module array using 9 series and 2 parallel connections of SHARP NT-R5E3E 175 W photovoltaic modules. In addition, we used data that were outputted under various fault conditions as the training samples for the CMAC and used this model to conduct the module array fault diagnosis after completing the training. The results of the training process and simulations indicate that the method proposed in this study requires fewer number of training times compared to other methods. In addition to significantly increasing the accuracy rate of the fault diagnosis, this model features a short training duration because the training process only tunes the weights of the exited memory addresses. Therefore, the fault diagnosis is rapid, and the detection tolerance of the diagnosis system is enhanced.

Intermediate photovoltaic system application experiment operational performance report. Volume 5 for Beverly High School, Beverly, MA

Energy Technology Data Exchange (ETDEWEB)

1982-02-01

Performance data are presented for the month of January, 1982 for a grid-connected photovoltaic power supply at a Massachusetts high school. Data presented include: monthly and daily electrical energy produced; monthly and daily solar energy incident on the array; monthly and daily array efficiency; plots of energy produced as a function of power level, voltage, cell temperature and time of day; power conditioner input, output and efficiency for each of two individual units and for the total power conditioning system; photovoltaic system efficiency; capacity factor; PV system to load and grid to load energies and corresponding dollar values; daily energy supplied to the load by the PV system; daily PV system availability; monthly and hourly insolation; monthly and hourly temperature average; monthly and hourly wind speed; wind direction distribution; average heating and cooling degree days; number of freeze/thaw cycles; and the data acquisition mode and recording interval plot. Also included are summaries of two problems with the operating data acquisition system. (LEW)

Optimal Sizing of Decentralized Photovoltaic Generation and Energy Storage Units for Malaysia Residential Household Using Iterative Method

Directory of Open Access Journals (Sweden)

Rahman Hasimah Abdul

2016-01-01

Full Text Available World’s fuel sources are decreasing, and global warming phenomena cause the necessity of urgent search for alternative energy sources. Photovoltaic generating system has a high potential, since it is clean, environmental friendly and secure energy sources. This paper presents an optimal sizing of decentralized photovoltaic system and electrical energy storage for a residential household using iterative method. The cost of energy, payback period, degree of autonomy and degree of own-consumption are defined as optimization parameters. A case study is conducted by employing Kuala Lumpur meteorological data, typical load profile from rural area in Malaysia, decentralized photovoltaic generation unit and electrical storage and it is analyzed in hourly basis. An iterative method is used with photovoltaic array variable from 0.1kW to 4.0kW and storage system variable from 50Ah to 400Ah was performed to determine the optimal design for the proposed system.

FY 1977 Annual report on Sunshine Project results. Survey and research on systems utilizing solar energy (Photovoltaic power generation systems); 1977 nendo taiyo energy riyo system chosa kenkyu seika hokokusho. Taiyoko hatsuden system

Energy Technology Data Exchange (ETDEWEB)

NONE

1978-03-31

This project is aimed at investigation on irradiation conditions of natural solar radiation to establish the performance evaluation methods; establishment of standard evaluation methods under natural solar radiation; and investigation on practical problems involved in the photovoltaic power generation systems. The research items are (1) photovoltaic power generation systems, and (2) standard evaluation methods for photovoltaic power generation systems installed on the ground. The item (1) includes the effect analysis in which existing Japanese residential buildings are selected to estimate possibility of installation of photovoltaic power generation systems and possible quantity of power generated; conceptual designs in which several systems conceivable at present are proposed and outlined, and a 30kW photovoltaic power generation system is taken up to investigate, e.g., solar cell arrays for the system, orthogonal conversion devices, associated facilities, conceptual designs of storage batteries, problems involved therein, and future research themes; and operation of the cell, which takes up operational examples of solar cell power sources, and operational problems viewed from the power transmission side. The item (2) proposes the standard evaluation methods (primary drafts) for the solar cell arrays and panels as those for photovoltaic power generation systems installed on the ground. (NEDO)

Photovoltaic Cells

OpenAIRE

Karolis Kiela

2012-01-01

The article deals with an overview of photovoltaic cells that are currently manufactured and those being developed, including one or several p-n junction, organic and dye-sensitized cells using quantum dots. The paper describes the advantages and disadvantages of various photovoltaic cells, identifies the main parameters, explains the main reasons for the losses that may occur in photovoltaic cells and looks at the ways to minimize them.Article in Lithuanian

Nanostructured Quantum Dots or Dashes in Photovoltaic Devices and Methods Thereof

Science.gov (United States)

Raffaele, Ryne P. (Inventor); Wilt, David M. (Inventor)

2015-01-01

A photovoltaic device includes one or more structures, an array of at least one of quantum dots and quantum dashes, at least one groove, and at least one conductor. Each of the structures comprises an intrinsic layer on one of an n type layer and a p type layer and the other one of the n type layer and the p type layer on the intrinsic layer. The array of at least one of quantum dots and quantum dashes is located in the intrinsic layer in at least one of the structures. The groove extends into at least one of the structures and the conductor is located along at least a portion of the groove.

Contextual Compression of Large-Scale Wind Turbine Array Simulations: Preprint

Energy Technology Data Exchange (ETDEWEB)

Gruchalla, Kenny M [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Brunhart-Lupo, Nicholas J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Potter, Kristin C [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Clyne, John [National Center for Atmospheric Research

2017-11-03

Data sizes are becoming a critical issue particularly for HPC applications. We have developed a user-driven lossy wavelet-based storage model to facilitate the analysis and visualization of large-scale wind turbine array simulations. The model stores data as heterogeneous blocks of wavelet coefficients, providing high-fidelity access to user-defined data regions believed the most salient, while providing lower-fidelity access to less salient regions on a block-by-block basis. In practice, by retaining the wavelet coefficients as a function of feature saliency, we have seen data reductions in excess of 94 percent, while retaining lossless information in the turbine-wake regions most critical to analysis and providing enough (low-fidelity) contextual information in the upper atmosphere to track incoming coherent turbulent structures. Our contextual wavelet compression approach has allowed us to deliver interactive visual analysis while providing the user control over where data loss, and thus reduction in accuracy, in the analysis occurs. We argue this reduced but contexualized representation is a valid approach and encourages contextual data management.

Photovoltaic barometer

International Nuclear Information System (INIS)

2013-01-01

After the euphoria of 2011, the European Union's photovoltaic market slowed right down in 2012. EurObserv'ER puts newly connected capacity in 2012 at 16.5 GWp compared to 22 GWp in 2011, which is a 25% drop. At global level the market generally held up, with just over 30 GWp installed, bolstered by the build-up of the American and Asian markets. The photovoltaic electricity generated in the EU reached 68.1 TWh in 2012. The article begins with the description of the worldwide situation of photovoltaic electricity, then details the situation for each EU member with the help of tables and charts and ends with the state of photovoltaic industry at the world scale

Three-level grid-connected photovoltaic inverter with maximum power point tracking

International Nuclear Information System (INIS)

Tsang, K.M.; Chan, W.L.

2013-01-01

Highlight: ► This paper reports a novel 3-level grid connected photovoltaic inverter. ► The inverter features maximum power point tracking and grid current shaping. ► The inverter can be acted as an active filter and a renewable power source. - Abstract: This paper presents a systematic way of designing control scheme for a grid-connected photovoltaic (PV) inverter featuring maximum power point tracking (MPPT) and grid current shaping. Unlike conventional design, only four power switches are required to achieve three output levels and it is not necessary to use any phase-locked-loop circuitry. For the proposed scheme, a simple integral controller has been designed for the tracking of the maximum power point of a PV array based on an improved extremum seeking control method. For the grid-connected inverter, a current loop controller and a voltage loop controller have been designed. The current loop controller is designed to shape the inverter output current while the voltage loop controller can maintain the capacitor voltage at a certain level and provide a reference inverter output current for the PV inverter without affecting the maximum power point of the PV array. Experimental results are included to demonstrate the effectiveness of the tracking and control scheme.

Comparative Study of Maximum Power Point Tracking Techniques for Photovoltaic Systems

Directory of Open Access Journals (Sweden)

Fernando Lessa Tofoli

2015-01-01

Full Text Available The generation of electricity from photovoltaic (PV arrays has been increasingly considered as a prominent alternative to fossil fuels. However, the conversion efficiency is typically low and the initial cost is still appreciable. A required feature of a PV system is the ability to track the maximum power point (MPP of the PV array. Besides, MPP tracking (MPPT is desirable in both grid-connected and stand-alone photovoltaic systems because the solar irradiance and temperature change throughout the day, as well as along seasons and geographical conditions, also leading to the modification of the I×V (current versus voltage and P×V (power versus voltage curves of the PV module. MPPT is also justified by the relatively high cost of the energy generated by PV systems if compared with other sources. Since there are various MPPT approaches available in the literature, this work presents a comparative study among four popular techniques, which are the fixed duty cycle method, constant voltage (CV, perturb and observe (P&O, and incremental conductance (IC. It considers different operational climatic conditions (i.e., irradiance and temperature, since the MPP is nonlinear with the environment status. PSIM software is used to validate the assumptions, while relevant results are discussed in detail.

The development and utilization of solar photovoltaic cells: An assessment of the potential for a new energy technology

Science.gov (United States)

Cyr, K. J.

1981-01-01

The Government set the goal of accelerating the adaptation of photovoltaics by reducing system costs to a competitive level and overcoming the technical, institutional, legal, environmental, and social barriers impeding the diffusion of photovoltaic technology. The technology of silicon solar arrays was examined and the status of development efforts are reviewed. The political, legal, economic, social, and environmental issues are discussed, and several methods for selecting development projects are described. A number of market forecasting techniques, including time trend, judgemental, and econometric methods, were reviewed, and the results of these models are presented.

MPPT for Photovoltaic System Using Nonlinear Controller

Directory of Open Access Journals (Sweden)

Ramsha Iftikhar

2018-01-01

Full Text Available Photovoltaic (PV system generates energy that varies with the variation in environmental conditions such as temperature and solar radiation. To cope up with the ever increasing demand of energy, the PV system must operate at maximum power point (MPP, which changes with load as well as weather conditions. This paper proposes a nonlinear backstepping controller to harvest maximum power from a PV array using DC-DC buck converter. A regression plane is formulated after collecting the data of the PV array from its characteristic curves to provide the reference voltage to track MPP. Asymptotic stability of the system is proved using Lyapunov stability criteria. The simulation results validate the rapid tracking and efficient performance of the controller. For further validation of the results, it also provides a comparison of the proposed controller with conventional perturb and observe (P&O and fuzzy logic-based controller (FLBC under abrupt changes in environmental conditions.

Photovoltaic mounting/demounting unit

DEFF Research Database (Denmark)

2014-01-01

The present invention relates to a photovoltaic arrangement comprising a photovoltaic assembly comprising a support structure defining a mounting surface onto which a photovoltaic module is detachably mounted; and a mounting/demounting unit comprising at least one mounting/demounting apparatus...... which when the mounting/demounting unit is moved along the mounting surface, causes the photovoltaic module to be mounted or demounted to the support structure; wherein the photovoltaic module comprises a carrier foil and wherein a total thickness of the photo voltaic module is below 500 muiotaeta....... The present invention further relates to an associated method for mounting/demounting photovoltaic modules....

A Practical Guide To Solar Array Simulation And PCDU Test

Science.gov (United States)

Schmitz, Noah; Carroll, Greg; Clegg, Russell

2011-10-01

Solar arrays consisting of multiple photovoltaic segments provide power to satellites and charge internal batteries for use during eclipse. Solar arrays have unique I-V characteristics and output power which vary with environmental and operational conditions such as temperature, irradiance, spin, and eclipse. Therefore, specialty power solutions are needed to properly test the satellite on the ground, especially the Power Control and Distribution Unit (PCDU) and the Array Power Regulator (APR.) This paper explores some practical and theoretical considerations that should be taken into account when choosing a commercial, off-the-shelf solar array simulator (SAS) for verification of the satellite PCDU. An SAS is a unique power supply with I-V output characteristics that emulate the solar arrays used to power a satellite. It is important to think about the strengths and the limitations of this emulation capability, how closely the SAS approximates a real solar panel, and how best to design a system using SAS as components.

Maximizing omnidirectional light harvesting in metal oxide hyperbranched array architectures

Science.gov (United States)

Wu, Wu-Qiang; Feng, Hao-Lin; Rao, Hua-Shang; Xu, Yang-Fan; Kuang, Dai-Bin; Su, Cheng-Yong

2014-05-01

The scrupulous design of nanoarchitectures and smart hybridization of specific active materials are closely related to the overall photovoltaic performance of an anode electrode. Here we present a solution-based strategy for the fabrication of well-aligned metal oxide-based nanowire-nanosheet-nanorod hyperbranched arrays on transparent conducting oxide substrates. For these hyperbranched arrays, we observe a twofold increment in dye adsorption and enhanced light trapping and scattering capability compared with the pristine titanium dioxide nanowires, and thus a power conversion efficiency of 9.09% is achieved. Our growth approach presents a strategy to broaden the photoresponse and maximize the light-harvesting efficiency of arrays architectures, and may lead to applications for energy conversion and storage, catalysis, water splitting and gas sensing.

Intermediate photovoltaic system application experiment operational performance report. Volume 4, for Beverly High School, Beverly, MA

Energy Technology Data Exchange (ETDEWEB)

1982-01-01

Performance data are presented for the months of November and December, 1981 for a photovoltaic power supply at a Massachusetts school building. The data include: monthly and daily electrical energy produced; monthly and daily solar energy received; monthly and daily array efficiency; energy produced as a function of power level, voltage, cell temperature, and hour of the day; input, output, and efficiency of two power conditioner units and for the total power conditioning system; energy supplied by the photovoltaic system to the load during each day and month; photovoltaic system efficiency; capacity factor; daily system availability; monthly and hourly insolation; heating and cooling degree days; number of freeze/thaw cycles per month; monthly and hourly ambient temperature; monthly and hourly wind speed; wind direction distribution; hourly cell temperature; and data acquisition mode and recording interval plot. (LEW)

A Simple and Reliable Method of Design for Standalone Photovoltaic Systems

Science.gov (United States)

Srinivasarao, Mantri; Sudha, K. Rama; Bhanu, C. V. K.

2017-06-01

Standalone photovoltaic (SAPV) systems are seen as a promoting method of electrifying areas of developing world that lack power grid infrastructure. Proliferations of these systems require a design procedure that is simple, reliable and exhibit good performance over its life time. The proposed methodology uses simple empirical formulae and easily available parameters to design SAPV systems, that is, array size with energy storage. After arriving at the different array size (area), performance curves are obtained for optimal design of SAPV system with high amount of reliability in terms of autonomy at a specified value of loss of load probability (LOLP). Based on the array to load ratio (ALR) and levelized energy cost (LEC) through life cycle cost (LCC) analysis, it is shown that the proposed methodology gives better performance, requires simple data and is more reliable when compared with conventional design using monthly average daily load and insolation.

Feasibility Study of Seawater Electrolysis for Photovoltaic/Fuel Cell Hybrid Power System for the Coastal Areas in Thailand

Science.gov (United States)

Srisiriwat, A.; Pirom, W.

2017-10-01

Solar photovoltaic cell and fuel cell are the practicable options to realize as a possible hybrid power system because the power of the sun cannot be utilized at night or cloudy days but hydrogen has been found as an ideal energy carrier for being transportable, storable, and converting energy though fuel cell. Hydrogen storage is chosen for its ability to obtain a clean energy option. Electrolysis, which is the simplest process to produce hydrogen, can be powered by the dc voltage from the photovoltaic cell instead of using the battery as power supply. This paper concentrates on a feasibility study of seawater electrolysis using photovoltaic power integrated fuel cell system for the coastal cities in Thailand. The proposed system composed of photovoltaic arrays, seawater electrolyzer and fuel cell is presented when the 10-kW of fuel cell electrical power is considered. The feasibility study of hydrogen production and energy analysis of this proposed system is also evaluated.

Double-pass photovoltaic / thermal (PV/T) solar collector with advanced heat transfer features

International Nuclear Information System (INIS)

Mohd Nazari Abu Bakar; Baharudin Yatim; Mohd Yusof Othman; Kamaruzzaman Sopian

2006-01-01

The use of PV/T in combination with concentrating reflectors has a potential to significantly increase power production from a given solar cell area. A prototype double-pass photovoltaic-thermal solar air collector with CPR and fins has been designed and fabricated and its performance over a range of operating conditions was studied. The absorber of the hybrid photovoltaic / thermal (PV/T) collector under investigation consists of an array of solar cells for generating electricity, compound parabolic concentrator (CPR) to increase the radiation intensity falling on the solar cells and fins attached to the back side of the absorber plate to improve heat transfer to the flowing air. The thermal, electrical and combined electrical and thermal efficiencies of the collector are presented and discussed

Applications of photovoltaics

International Nuclear Information System (INIS)

Pearsall, N.

1999-01-01

The author points out that although photovoltaics can be used for generating electricity for the same applications as many other means of generation, they really come into their own where disadvantages associated with an intermittent unpredictable supply are not severe. The paper discusses the advantages and disadvantages to be taken into account when considering a photovoltaic power system. Five main applications, based on the system features, are listed and explained. They are: consumer, professional, rural electrification, building-integrated, centralised grid connected and space power. A brief history of the applications of photovoltaics is presented with statistical data on the growth of installed capacity since 1992. The developing market for photovoltaics is discussed together with how environmental issues have become a driver for development of building-integrated photovoltaics

Simple economic evaluation and applications experiments for photovoltaic systems for remote sites

Energy Technology Data Exchange (ETDEWEB)

Rios, M. Jr.

1980-01-01

A simple evaluation of the cost effectiveness of photovoltaic systems is presented. The evaluation is based on a calculation of breakeven costs of photovoltaics (PV) arrays with the levelized costs of two alternative energy sources (1) extension of the utility grid and (2) diesel generators. A selected number of PV applications experiments that are in progress in remote areas of the US are summarized. These applications experiments range from a 23 watt insect survey trap to a 100 kW PV system for a national park complex. It is concluded that PV systems for remote areas are now cost effective in remote small applications with commercially available technology and will be cost competitive for intermediate scale systems (approx. 10 kW) in the 1980s if the DOE 1986 Commercial Readiness Goals are achieved.

Customized color patterning of photovoltaic cells

Science.gov (United States)

Cruz-Campa, Jose Luis; Nielson, Gregory N.; Okandan, Murat; Lentine, Anthony L.; Resnick, Paul J.; Gupta, Vipin P.

2016-11-15

Photovoltaic cells and photovoltaic modules, as well as methods of making and using such photovoltaic cells and photovoltaic modules, are disclosed. More particularly, embodiments of the photovoltaic cells selectively reflect visible light to provide the photovoltaic cells with a colorized appearance. Photovoltaic modules combining colorized photovoltaic cells may be used to harvest solar energy while providing a customized appearance, e.g., an image or pattern.

Will we exceed 50% efficiency in photovoltaics?

Science.gov (United States)

Luque, Antonio

2011-08-01

Solar energy is the most abundant and reliable source of energy we have to provide for the multi-terawatt challenge we are facing. Although huge, this resource is relatively dispersed. High conversion efficiency is probably necessary for cost effectiveness. Solar cell efficiencies above 40% have been achieved with multijunction (MJ) solar cells. These achievements are here described. Possible paths for improvement are hinted at including third generation photovoltaics concepts. It is concluded that it is very likely that the target of 50% will eventually be achieved. This high efficiency requires operating under concentrated sunlight, partly because concentration helps increase the efficiency but mainly because the cost of the sophisticated cells needed can only be paid by extracting as much electric power form each cell as possible. The optical challenges associated with the concentrator optics and the tools for overcoming them, in particular non-imaging optics, are briefly discussed and the results and trends are described. It is probable that optical efficiency over 90% will be possible in the future. This would lead to a module efficiency of 45%. The manufacturing of a concentrator has to be addressed at three levels of integration: module, array, and photovoltaic (PV) subfield. The PV plant as a whole is very similar than a flat module PV plant with two-axes tracking. At the module level, the development of tools for easy manufacturing and quality control is an important topic. Furthermore, they can accommodate in different position cells with different spectral sensitivities so complementing the effort in manufacturing MJ cells. At the array level, a proper definition of the nameplate watts, since the diffuse light is not used, is under discussion. The cost of installation of arrays in the field can be very much reduced by self aligning tracking control strategies. At the subfield level, aspects such as the self shadowing of arrays causes the CPV subfields to

Photovoltaic systems engineering

CERN Document Server

Messenger, Roger A

2010-01-01

BackgroundPopulation and Energy DemandEnergy UnitsCurrent World Energy Use PatternsExponential GrowthHubbert's Gaussian ModelNet Energy, Btu Economics, and the Test for SustainabilityDirect Conversion of Sunlight to Electricity with PhotovoltaicsThe SunThe Solar SpectrumThe Effect of Atmosphere on SunlightSunlight SpecificsCapturing SunlightIntroduction to PV SystemsThe PV CellThe PV ModuleThe PV ArrayEnergy StoragePV System LoadsPV System AvailabilityAssociated System Electronic ComponentsGeneratorsBalance of System (BOS) ComponentsGrid-Connected Utility-Interactive PV SystemsApplicable Codes and StandardsDesign Considerations for Straight Grid-Connected PV SystemsDesign of a System Based on Desired Annual System PerformanceDesign of a System Based on Available Roof SpaceDesign of a Microinverter-Based SystemDesign of a Nominal 21 kW System that Feeds a Three-Phase Distribution PanelDesign of a Nominal 250 kW SystemSystem Performance MonitoringMechanical ConsiderationsImportant Properties of MaterialsEstabli...

Signal processing for solar array monitoring, fault detection, and optimization

CERN Document Server

Braun, Henry; Spanias, Andreas

2012-01-01

Although the solar energy industry has experienced rapid growth recently, high-level management of photovoltaic (PV) arrays has remained an open problem. As sensing and monitoring technology continues to improve, there is an opportunity to deploy sensors in PV arrays in order to improve their management. In this book, we examine the potential role of sensing and monitoring technology in a PV context, focusing on the areas of fault detection, topology optimization, and performance evaluation/data visualization. First, several types of commonly occurring PV array faults are considered and detection algorithms are described. Next, the potential for dynamic optimization of an array's topology is discussed, with a focus on mitigation of fault conditions and optimization of power output under non-fault conditions. Finally, monitoring system design considerations such as type and accuracy of measurements, sampling rate, and communication protocols are considered. It is our hope that the benefits of monitoring presen...

Rapid thermal cycling of new technology solar array blanket coupons

Science.gov (United States)

Scheiman, David A.; Smith, Bryan K.; Kurland, Richard M.; Mesch, Hans G.

1990-01-01

NASA Lewis Research Center is conducting thermal cycle testing of a new solar array blanket technologies. These technologies include test coupons for Space Station Freedom (SSF) and the advanced photovoltaic solar array (APSA). The objective of this testing is to demonstrate the durability or operational lifetime of the solar array interconnect design and blanket technology within a low earth orbit (LEO) or geosynchronous earth orbit (GEO) thermal cycling environment. Both the SSF and the APSA array survived all rapid thermal cycling with little or no degradation in peak performance. This testing includes an equivalent of 15 years in LEO for SSF test coupons and 30 years of GEO plus ten years of LEO for the APSA test coupon. It is concluded that both the parallel gap welding of the SSF interconnects and the soldering of the APSA interconnects are adequately designed to handle the thermal stresses of space environment temperature extremes.

Examination of a Junction-Box Adhesion Test for Use in Photovoltaic Module Qualification: Preprint

Energy Technology Data Exchange (ETDEWEB)

Miller, D. C.; Wohlgemuth, J. H.

2012-08-01

Engineering robust adhesion of the junction-box (j-box) is a hurdle typically encountered by photovoltaic (PV) module manufacturers during product development. There are historical incidences of adverse effects (e.g., fires) caused when the j-box/adhesive/module system has failed in the field. The addition of a weight to the j-box during the 'damp heat' IEC qualification test is proposed to verify the basic robustness of its adhesion system. The details of the proposed test will be described, in addition to the preliminary results obtained using representative materials and components. The described discovery experiments examine moisture-cured silicone, foam tape, and hot-melt adhesives used in conjunction with PET or glass module 'substrates.' To be able to interpret the results, a set of material-level characterizations was performed, including thermogravimetric analysis, differential scanning calorimetry, and dynamic mechanical analysis. PV j-boxes were adhered to a substrate, loaded with a prescribed weight, and then placed inside an environmental chamber (at 85C, 85% relative humidity). Some systems did not remain attached through the discovery experiments. Observed failure modes include delamination (at the j-box/adhesive or adhesive/substrate interface) and phase change/creep. The results are discussed in the context of the application requirements, in addition to the plan for the formal experiment supporting the proposed modification to the qualification test.

Geometric photovoltaics applied to amorphous silicon thin film solar cells

Science.gov (United States)

Kirkpatrick, Timothy

Geometrically generalized analytical expressions for device transport are derived from first principles for a photovoltaic junction. Subsequently, conventional planar and unconventional coaxial and hemispherical photovoltaic architectures are applied to detail the device physics of the junction based on their respective geometry. For the conventional planar cell, the one-dimensional transport equations governing carrier dynamics are recovered. For the unconventional coaxial and hemispherical junction designs, new multi-dimensional transport equations are revealed. Physical effects such as carrier generation and recombination are compared for each cell architecture, providing insight as to how non-planar junctions may potentially enable greater energy conversion efficiencies. Numerical simulations are performed for arrays of vertically aligned, nanostructured coaxial and hemispherical amorphous silicon solar cells and results are compared to those from simulations performed for the standard planar junction. Results indicate that fundamental physical changes in the spatial dependence of the energy band profile across the intrinsic region of an amorphous silicon p-i-n junction manifest as an increase in recombination current for non-planar photovoltaic architectures. Despite an increase in recombination current, however, the coaxial architecture still appears to be able to surpass the efficiency predicted for the planar geometry, due to the geometry of the junction leading to a decoupling of optics and electronics.

Nanoscale imaging of photocurrent enhancement by resonator array photovoltaic coatings

Science.gov (United States)

Ha, Dongheon; Yoon, Yohan; Zhitenev, Nikolai B.

2018-04-01

Nanoscale surface patterning commonly used to increase absorption of solar cells can adversely impact the open-circuit voltage due to increased surface area and recombination. Here, we demonstrate absorptivity and photocurrent enhancement using silicon dioxide (SiO2) nanosphere arrays on a gallium arsenide (GaAs) solar cell that do not require direct surface patterning. Due to the combined effects of thin-film interference and whispering gallery-like resonances within nanosphere arrays, there is more than 20% enhancement in both absorptivity and photocurrent. To determine the effect of the resonance coupling between nanospheres, we perform a scanning photocurrent microscopy based on a near-field scanning optical microscopy measurement and find a substantial local photocurrent enhancement. The nanosphere-based antireflection coating (ARC), made by the Meyer rod rolling technique, is a scalable and a room-temperature process; and, can replace the conventional thin-film-based ARCs requiring expensive high-temperature vacuum deposition.

Off-grid photovoltaic vehicle charge using second life lithium batteries: An experimental and numerical investigation

International Nuclear Information System (INIS)

Tong, Shi Jie; Same, Adam; Kootstra, Mark A.; Park, Jae Wan

2013-01-01

Highlights: ► We have examined the feasibility of a second life battery pack for an off-grid photovoltaic vehicle charging system. ► The second life battery successfully achieved the desired function using simple control methods. ► The system has been modeled using equivalent circuit techniques. ► The model can simulate the system’s performance under different application scenarios. - Abstract: Partially degraded lithium batteries from automotive applications, also known as second life batteries, are becoming more available for secondary applications due to the increasing market share of plug-in hybrid and electric vehicles. This study examines the feasibility of installing a second life battery pack in an off-grid photovoltaic vehicle charging system. The system was constructed using a photovoltaic array to charge a battery pack via a maximum power point tracking controller and later charge a vehicle via an inverter. The battery pack was configured using 135 second life LiFePO 4 based battery cells, selected based on remaining capacity, connected to form a nine parallel by 15 serial battery pack with accessible storage capacity of 13.9 kW h. Experimental results show that the proposed second life battery system successfully achieves the desired function with a simple system structure and control methods. A numerical simulation was performed by constructing an equivalent system model, where the photovoltaic array and battery pack were modeled using equivalent circuit techniques. The model was parameterized and validated via testing of the system. Coupled with weather data, the model can simulate the system’s performance under different application scenarios. The numerical investigation reveals that the proposed system, using second life batteries, can achieve similar performance to systems using new lithium batteries, but at a reduced cost

Analysis of the photovoltaic solar energy capacity of residential rooftops in Andalusia (Spain)

Energy Technology Data Exchange (ETDEWEB)

Ordonez, J.; Jadraque, E.; Alegre, J.; Martinez, G. [Department of Civil Engineering, University of Granada (Spain)

2010-09-15

Fossil fuel energy resources are becoming increasingly scarce. Given the negative environmental impacts (e.g. greenhouse gas emissions) that accompany their use, it is hardly surprising that the development of renewable energies has become a major priority in the world today. Andalusia, with a mean solar radiation of 4.75 kWh/m{sup 2} per day and a surface area of 87,597 km{sup 2}, is the region in Europe with the highest solar energy potential. This research study determined the solar energy potential in Andalusia for grid-connected photovoltaic systems installed on residential rooftops. A methodology was developed for this purpose, which first involved a description of building characteristics, followed by the calculation of the useful roof surface area where photovoltaic arrays could be installed. In the next phase of the study, the mean solar irradiation characteristics were defined as well as the technical parameters of the photovoltaic systems. All of these factors allowed us to estimate the amount of electricity that could be potentially generated per year by solar panels. (author)

Optimal sizing method for constituent elements of stand-alone photovoltaic power systems

Energy Technology Data Exchange (ETDEWEB)

Otsuka, Hirotada; Oi, Yoichi [Hokuriku Electric Power Co., Inc. Toyama (Japan)

1988-12-25

The purpose of the report was to calculate the optimal volume of constituent elements of stand-alone photovoltaic power systems, based on the distribution of global radiation on an inclined surface (herein-after called flux of solar radiation), which had been previously measured, and the size of load to be supplied. The least power generation cost was calculated, supposing that setting load was 176kWh/month and the loss of load probability (LOLP) was 1%, by using actual amount of solar radiation in May 1985. The cost was divided into two components: one was proportionate to the size of solar cell, and the other was in proportion to the battery volume. And then, the cost of twenty-year operation(TLC) was calculated. The size of array and the battery volume, which minimize the cost, can be determined when TLC is differentiate. Since auxiliary power source is not attached to this system, it is necessary to restrict the load in order to meet the electric power shortage. In case of the cost at construction in 1984, a standard model indicating the least power generation cost is a photovoltaic system with the array size of A=49.0m{sup 2} and the battery volume of Q=568(Ah). 4 refs., 9 figs., 10 tabs.

Maximun power point tracker of photovoltaic s panels for stand alone systems

International Nuclear Information System (INIS)

Stoll, R; Manno, R

2005-01-01

The low energetic efficiency of photovoltaic s panels is known, in addition, due to the use of linear regulators, which dissipate an important bit of the generated energy, the efficiency of the photovoltaic systems is still smaller.Also, the I-V characteristic curve of the photovoltaic modules depends on the solar radiation and the own temperature; consequently, the maximum power point (Wp) changes permanently.In conclusion, to produce electricity with photovoltaic panels is very expensive. However due to preserve the environment this technology is widely used.With the purpose of optimizing the amount of energy produced by the photovoltaic system, two complementary methods are used.One is the Maximum Power Point Tracker (MPPT) system and the other one is the Solar Tracker system.The objective of this project is to reduce that cost increasing the amount of energy produced by the solar panels using a Maximum Power Point Tracker system.This device consists of a DC/DC buck converter of high performance, controlled by a PIC 16F873 micro controller; which carries out the conversions of the analogical signals of the solar array to digital signals (ADC), the PIC output digital signals to the PWM control of the power FET (DAC), and calculates the Duty Cycle (D) for the point of I-V curve where this product becomes maximum.Measurements for different loads and battery charges were made.With the obtained results, the comparisons with a conventional system were made, a greater cession of energy to the load is observed.The main conclusion of this work is: Using a MPPT device to making work the PV module during the greater possible time near the maximum power point, the efficiency of the photovoltaic systems can be increased

Photovoltaic energy barometer

International Nuclear Information System (INIS)

Anon.

2007-01-01

The european photovoltaic market once again reached the heights in 2006, thanks to the dynamism of the German market. White paper objectives have thus been fulfilled four years ahead of schedule. The european photovoltaic sector remains however very heterogeneous with both an ultra-dominant German market (estimated at 1150 MWp in 2006) and other countries of the European Union that vary from a few kWP to a few dozen MWp. This analysis provides statistical data on the market, the capacity installed during 2005 and 2006, the photovoltaic parks and the evolution of the photovoltaic cell production. (A.L.B.)

Solar photovoltaic power forecasting using optimized modified extreme learning machine technique

Directory of Open Access Journals (Sweden)

Manoja Kumar Behera

2018-06-01

Full Text Available Prediction of photovoltaic power is a significant research area using different forecasting techniques mitigating the effects of the uncertainty of the photovoltaic generation. Increasingly high penetration level of photovoltaic (PV generation arises in smart grid and microgrid concept. Solar source is irregular in nature as a result PV power is intermittent and is highly dependent on irradiance, temperature level and other atmospheric parameters. Large scale photovoltaic generation and penetration to the conventional power system introduces the significant challenges to microgrid a smart grid energy management. It is very critical to do exact forecasting of solar power/irradiance in order to secure the economic operation of the microgrid and smart grid. In this paper an extreme learning machine (ELM technique is used for PV power forecasting of a real time model whose location is given in the Table 1. Here the model is associated with the incremental conductance (IC maximum power point tracking (MPPT technique that is based on proportional integral (PI controller which is simulated in MATLAB/SIMULINK software. To train single layer feed-forward network (SLFN, ELM algorithm is implemented whose weights are updated by different particle swarm optimization (PSO techniques and their performance are compared with existing models like back propagation (BP forecasting model. Keywords: PV array, Extreme learning machine, Maximum power point tracking, Particle swarm optimization, Craziness particle swarm optimization, Accelerate particle swarm optimization, Single layer feed-forward network

Impact of Battery’s Model Accuracy on Size Optimization Process of a Standalone Photovoltaic System

Directory of Open Access Journals (Sweden)

Ibrahim Anwar Ibrahim

2016-09-01

Full Text Available This paper presents a comparative study between two proposed size optimization methods based on two battery’s models. Simple and complex battery models are utilized to optimally size a standalone photovoltaic system. Hourly meteorological data are used in this research for a specific site. Results show that by using the complex model of the battery, the cost of the system is reduced by 31%. In addition, by using the complex battery model, the sizes of the PV array and the battery are reduced by 5.6% and 30%, respectively, as compared to the case which is based on the simple battery model. This shows the importance of utilizing accurate battery models in sizing standalone photovoltaic systems.

Facile Hydrothermal Preparation of ZNO/CO3O4 Heterogeneous Nanostructures and its Photovoltaic Effect

Science.gov (United States)

Wei, Fanan; Jiang, Minlin; Liu, Lianqing

2015-07-01

Photovoltaic technology offers great potential in the replacement of fossil fuel resources, but still suffers from high device fabrication cost. Herein, we attempted to provide a solution to these issues with heterogeneous nanostructures. Firstly, Zinc oxide (ZnO)/cobalt oxide (Co3O4) heterojunction nanowires are prepared through facile fabrication methods. By assembling Co(OH)2 nanoplates on ZnO nanowire arrays, the ZnO/Co3O4 heterogeneous nanostructures are uniformly synthesized on ITO coated glass and wafer. Current (I)-voltage (V) measurement through conductive atomic force microscope shows excellent photovoltaic effect. And, the heterojunction nanostructures shows unprecedented high open circuit voltage. Therefore, the potential application of the heterogeneous nanostructures in solar cells is demonstrated.

Thermionic photovoltaic energy converter

Science.gov (United States)

Chubb, D. L. (Inventor)

1985-01-01

A thermionic photovoltaic energy conversion device comprises a thermionic diode mounted within a hollow tubular photovoltaic converter. The thermionic diode maintains a cesium discharge for producing excited atoms that emit line radiation in the wavelength region of 850 nm to 890 nm. The photovoltaic converter is a silicon or gallium arsenide photovoltaic cell having bandgap energies in this same wavelength region for optimum cell efficiency.

Transparent ultraviolet photovoltaic cells.

Science.gov (United States)

Yang, Xun; Shan, Chong-Xin; Lu, Ying-Jie; Xie, Xiu-Hua; Li, Bing-Hui; Wang, Shuang-Peng; Jiang, Ming-Ming; Shen, De-Zhen

2016-02-15

Photovoltaic cells have been fabricated from p-GaN/MgO/n-ZnO structures. The photovoltaic cells are transparent to visible light and can transform ultraviolet irradiation into electrical signals. The efficiency of the photovoltaic cells is 0.025% under simulated AM 1.5 illumination conditions, while it can reach 0.46% under UV illumination. By connecting several such photovoltaic cells in a series, light-emitting devices can be lighting. The photovoltaic cells reported in this Letter may promise the applications in glass of buildings to prevent UV irradiation and produce power for household appliances in the future.

Three-phase Photovoltaic Systems

DEFF Research Database (Denmark)

Kerekes, Tamas; Sera, Dezso; Máthé, Lászlo

2015-01-01

, detailing the different photovoltaic inverter structures and topologies as well as discussing the different control layers within a grid-connected photovoltaic plant. Modulation schemes for various photovoltaic inverter topologies, grid synchronization, current control, active and reactive power control......Photovoltaic technology has experienced unprecedented growth in the last two decades, transforming from mainly off-grid niche generation to a major renewable energy technology, reaching approximately 180 GW of capacity worldwide at the end of 2014. Large photovoltaic power plants interfacing...... the grid through a three-phase power electronic converter are now well on the way to becoming a major player in the power system in many countries. Therefore, this article gives an overview of photovoltaic systems with a focus on three-phase applications, presenting these both from a hardware point of view...

Recent developments in photovoltaic energy by ERDA/NASA-LeRC

Science.gov (United States)

Deyo, J. N.

1977-01-01

Application development activities were designed to stimulate the market for photovoltaics so that as costs are reduced there will be an increasing market demand to encourage the expansion of industrial solar array production capacity. Supporting these application development activities are tasks concerned with: (1) establishing standards and methodology for terrestrial solar cell calibration; (2) conducting standard and diagnostic measurements on solar cells and modules; and (3) conducting real time and accelerated testing of solar cell modules and materials of construction under outdoor sunlight conditions.

Flexo-photovoltaic effect.

Science.gov (United States)

Yang, Ming-Min; Kim, Dong Jik; Alexe, Marin

2018-04-19

It is highly desirable to discover photovoltaic mechanisms that enable a higher efficiency of solar cells. Here, we report that the bulk photovoltaic effect, which is free from the thermodynamic Shockley-Queisser limit but usually manifested only in noncentrosymmetric (piezoelectric or ferroelectric) materials, can be realized in any semiconductor, including silicon, by mediation of flexoelectric effect. We introduce strain gradients using either an atomic force microscope or a micron-scale indentation system, creating giant photovoltaic currents from centrosymmetric single crystals of SrTiO 3 , TiO 2 , and Si. This strain-gradient-induced bulk photovoltaic effect, which we call the flexo-photovoltaic effect, functions in the absence of a p - n junction. This finding may extend present solar cell technologies by boosting the solar energy conversion efficiency from a wide pool of established semiconductors. Copyright © 2018, American Association for the Advancement of Science.

Development of an Electrostatically Clean Solar Array Panel

Science.gov (United States)

Stern, Theodore G.; Krumweide, Duane; Gaddy, Edward; Katz, Ira

2000-01-01

The results of design, analysis, and qualification of an Electrostatically Clean Solar Array (ECSA) panel are described. The objective of the ECSA design is to provide an electrostatic environment that does not interfere with sensitive instruments on scientific spacecraft. The ECSA design uses large, ITO-coated coverglasses that cover multiple solar cells, an aperture grid that covers the intercell areas, stress-relieved interconnects for connecting the aperture grid to the coverglasses, and edge clips to provides an electromagnetically shielded enclosure for the solar array active circuitry. Qualification coupons were fabricated and tested for photovoltaic response, conductivity, and survivability to launch acoustic and thermal cycling environments simulating LEO and GEO missions. The benefits of reducing solar panel interaction with the space environment are also discussed.

Photovoltaic cell

Science.gov (United States)

Gordon, Roy G.; Kurtz, Sarah

1984-11-27

In a photovoltaic cell structure containing a visibly transparent, electrically conductive first layer of metal oxide, and a light-absorbing semiconductive photovoltaic second layer, the improvement comprising a thin layer of transition metal nitride, carbide or boride interposed between said first and second layers.

Design of Photovoltaic Power System for a Precursor Mission for Human Exploration of Mars

Science.gov (United States)

Mcnatt, Jeremiah; Landis, Geoffrey; Fincannon, James

2016-01-01

This project analyzed the viability of a photovoltaic power source for technology demonstration mission to demonstrate Mars in-situ resource utilization (ISRU) to produce propellant for a future human mission, based on technology available within the next ten years. For this assessment, we performed a power-system design study for a scaled ISRU demonstrator lander on the Mars surface based on existing solar array technologies.

Photovoltaic device

DEFF Research Database (Denmark)

2011-01-01

A photovoltaic cell module including a plurality of serially connected photovoltaic cells on a common substrate, each including a first electrode, a printed light-harvesting layer and a printed second electrode, wherein at least one of the electrodes is transparent, and wherein the second electrode...... of a first cell is printed such that it forms an electrical contact with the first electrode of an adjacent second cell without forming an electrical contact with the first electrode of the first cell or the light-harvesting layer of the second cell, and a method of making such photovoltaic cell modules....

Broadband photocurrent enhancement and light-trapping in thin film Si solar cells with periodic Al nanoparticle arrays on the front

DEFF Research Database (Denmark)

Uhrenfeldt, C.; Villesen, T. F.; Tetu, A.

2015-01-01

Plasmonic resonances in metal nanoparticles are considered candidates for improved thin film Si photovoltaics. In periodic arrays the influence of collective modes can enhance the resonant properties of such arrays. We have investigated the use of periodic arrays of Al nanoparticles placed...... on the front of a thin film Si test solar cell. It is demonstrated that the resonances from the Al nanoparticle array cause a broadband photocurrent enhancement ranging from the ultraviolet to the infrared with respect to a reference cell. From the experimental results as well as from numerical simulations...

Advances in thin-film solar cells for lightweight space photovoltaic power

Science.gov (United States)

Landis, Geoffrey A.; Bailey, Sheila G.; Flood, Dennis J.

1989-01-01

The development of photovoltaic arrays beyond the next generation is discussed with attention given to the potentials of thin-film polycrystalline and amorphous cells. Of particular importance is the efficiency (the fraction of incident solar energy converted to electricity) and specific power (power to weight ratio). It is found that the radiation tolerance of thin-film materials is far greater than that of single crystal materials. CuInSe2 shows no degradation when exposed to 1-MeV electrons.

Advancements of the Lightweight Integrated Solar Array and Transceiver (LISA-T) Small Spacecraft System

Science.gov (United States)

Lockett, Tiffany Russell; Martinez, Armando; Boyd, Darren; SanSouice, Michael; Farmer, Brandon; Schneider, Todd; Laue, Greg; Fabisinski, Leo; Johnson, Les; Carr, John A.

2015-01-01

This paper describes recent advancements of the Lightweight Integrated Solar Array and Transceiver (LISA-T) currently being developed at NASA's Marshall Space Flight Center. The LISA-T array comprises a launch stowed, orbit deployed structure on which thin-film photovoltaic (PV) and antenna devices are embedded. The system provides significant electrical power generation at low weights, high stowage efficiency, and without the need for solar tracking. Leveraging high-volume terrestrial-market PVs also gives the potential for lower array costs. LISA-T is addressing the power starvation epidemic currently seen by many small-scale satellites while also enabling the application of deployable antenna arrays. Herein, an overview of the system and its applications are presented alongside sub-system development progress and environmental testing plans.

Characteristics of heat transfer and fluid flow in a channel with single-row plates array oblique to flow direction for photovoltaic/thermal system

International Nuclear Information System (INIS)

Ali, Ahmed Hamza H.; Ahmed, Mahmoud; Youssef, M.S.

2010-01-01

This study has been carried out to investigate the characteristics of convective heat transfer and fluid flow for a single row of oblique plates array to the flow direction inside a channel. The flow inside the channel is laminar and the plates array have spanwise distance between the plates and heated by radiation. This configuration has been designed to be used for Photovoltaic/Thermal system (PV/T) applications. The theoretical results are validated with measured values, and a good agreement prevailed. The results show that an increase in the plate oblique angle (γ) in the range from 0 to 15 degrees, leads to an increase in the Nusselt number (Nu) up to a maximum value and then decreases. The oblique angle at the maximum value of Nu depends on the flow Reynolds Number (Re), and (l w /l pl ), where (l w /l pl ) is defined as the ratio of the plates' spacing at zero oblique angle to the plate length. Furthermore, increasing (l w /l pl ) results in a significant increase in the heat transfer coefficient depending on the values of Re, and plate oblique angle (γ). In addition, increasing (γ) from 0 to 15 degrees results in a decrease in the friction factor up to a certain value, after which the friction value approaches a constant value depending on Re value and (l w /l pl ). It was found that for any value of the plate oblique angle (γ), the friction factor decreases with the increase of the values of (l w /l pl ) and Re, respectively.

Synthesis, structure and photoelectrochemical properties of single crystalline silicon nanowire arrays

International Nuclear Information System (INIS)

Dalchiele, E.A.; Martin, F.; Leinen, D.; Marotti, R.E.; Ramos-Barrado, J.R.

2010-01-01

In the present work, n-type silicon nanowire (n-SiNW) arrays have been synthesized by self-assembly electroless metal deposition (EMD) nanoelectrochemistry. The synthesized n-SiNW arrays have been submitted to scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and optical studies. Initial probes of the solar device conversion properties and the photovoltaic parameters such as short-circuit current, open-circuit potential, and fill factor of the n-SiNW arrays have been explored using a liquid-junction in a photoelectrochemical (PEC) system under white light. Moreover, a direct comparison between the PEC performance of a polished n-Si(100) and the synthesized n-SiNW array photoelectrodes has been done. The PEC performance was significantly enhanced on the n-SiNWs photoelectrodes compared with that on polished n-Si(100).

A modular strategy for isolated photovoltaic systems based on microcontroller

Energy Technology Data Exchange (ETDEWEB)

Pernia, Alberto M.; Arias, Jorge; Prieto, Miguel J.; Martinez, Juan Angel [University of Oviedo, Department of Electrical Engineering, Campus de Viesques s/n, 33204 Gijon, Asturias (Spain)

2009-07-15

Many different types of commercial regulators can be found in the market. These devices can be basically divided into two categories according to their operation mode: those which modulate the input voltage using PWM (pulse-width modulation) in order to generate the output voltage required to charge the batteries; and those which make the PV (photovoltaic) array operate in their MPP (maximum power point), which can be tracked in several different ways. The former are normally used for low-power applications, whereas the latter can provide an increase of power up to 25% as compared to their PWM counterpart. This paper presents a regulator which can operate in the maximum power point of PV arrays by means of a microcontroller. A simple, highly-accurate algorithm suitable to be implemented in a low-cost microcontroller has been developed in order to make PV arrays track and operate in their maximum power point. The control strategy proposed allows parallel connection of different regulators, thus making it possible to keep and integrate previous equipment. (author)

Field trial of rural solar photovoltaic system

Science.gov (United States)

Basu, P.; Mukhopadhyay, K.; Banerjee, T.; Das, S.; Saha, H.

Experience, costs, and performance of photovoltaic (PV) systems set up in a remote Indian village to power an adult literacy center and an irrigation pump are described. The center was furnished with a 14-module, 200 W array to power a television and three fluorescent lamps. The pumping installation has 20 modules for a 300 W output directly coupled to a 300-W dc pump motor. Data were gathered on the open circuit voltage, short circuit current, specific gravity of the battery fluid, degradation of the cells, nominal operating temperature of the cells, load currents, Amp-hours, water flow rate (pump), and the static head and draw down rate (pump). Monitoring of the array performances in the dusty environment showed that once/week cleaning is necessary. Al-substrates cracked at the center installation and sealant evaporation caused condensation which degraded the light transmissivity and thereby the short-circuit current of the modules. The combination of low-efficiency (5 pct) cells and cheap labor demonstrated economic operation without high-efficiency cells.

Spectral analysis to detection of short circuit fault of solar photovoltaic modules in strings

International Nuclear Information System (INIS)

Sevilla-Camacho, P.Y.; Robles-Ocampo, J.B.; Zuñiga-Reyes, Marco A.

2017-01-01

This research work presents a method to detect the number of short circuit faulted solar photovoltaic modules in strings of a photovoltaic system by taking into account speed, safety, and non-use of sensors and specialized and expensive equipment. The method consists on apply the spectral analysis and statistical techniques to the alternating current output voltage of a string and detect the number of failed modules through the changes in the amplitude of the component frequency of 12 kHz. For that, the analyzed string is disconnected of the array; and a small pulsed voltage signal of frequency of 12 kHz introduces him under dark condition and controlled temperature. Previous to the analysis, the signal is analogic filtered in order to reduce the direct current signal component. The spectral analysis technique used is the Fast Fourier Transform. The obtained experimental results were validated through simulation of the alternating current equivalent circuit of a solar cell. In all experimental and simulated test, the method allowed to identify correctly the number of photovoltaic modules with short circuit in the analyzed string. (author)

A software application for energy flow simulation of a grid connected photovoltaic system

International Nuclear Information System (INIS)

Hamad, Ayman A.; Alsaad, Mohammad A.

2010-01-01

A computer software application was developed to simulate hourly energy flow of a grid connected photovoltaic system. This software application enables conducting an operational evaluation of a studied photovoltaic system in terms of energy exchange with the electrical grid. The system model consists of a photovoltaic array, a converter and an optional generic energy storage component that supports scheduled charging/discharging. In addition to system design parameters, the software uses hourly solar data and hourly load data to determine the amount of energy exchanged with electrical grid for each hour of the simulated year. The resulting information is useful in assessing the impact of the system on demand for electrical energy of a building that uses it. The software also aggregates these hourly results in daily, monthly and full year sums. The software finds the financial benefit of the system as the difference in grid electrical energy cost between two simultaneously considered cases. One is with load supplied only by the electrical grid, while the other is with the photovoltaic system present and contributing energy. The software supports the energy pricing scheme used in Jordan for domestic consumers, which is based on slices of monthly consumption. By projecting the yearly financial results on the system lifetime, the application weighs the financial benefit resulting from using the system against its cost, thus facilitating an economical evaluation.

MODEL PREDICTIVE CONTROL FOR PHOTOVOLTAIC STATION MAXIMUM POWER POINT TRACKING SYSTEM

Directory of Open Access Journals (Sweden)

I. Elzein

2015-01-01

Full Text Available The purpose of this paper is to present an alternative maximum power point tracking, MPPT, algorithm for a photovoltaic module, PVM, to produce the maximum power, Pmax, using the optimal duty ratio, D, for different types of converters and load matching.We present a state-based approach to the design of the maximum power point tracker for a stand-alone photovoltaic power generation system. The system under consideration consists of a solar array with nonlinear time-varying characteristics, a step-up converter with appropriate filter.The proposed algorithm has the advantages of maximizing the efficiency of the power utilization, can be integrated to other MPPT algorithms without affecting the PVM performance, is excellent for Real-Time applications and is a robust analytical method, different from the traditional MPPT algorithms which are more based on trial and error, or comparisons between present and past states. The procedure to calculate the optimal duty ratio for a buck, boost and buck-boost converters, to transfer the maximum power from a PVM to a load, is presented in the paper. Additionally, the existence and uniqueness of optimal internal impedance, to transfer the maximum power from a photovoltaic module using load matching, is proved.

Urban photovoltaic electricity policies

Energy Technology Data Exchange (ETDEWEB)

NONE

2009-10-15

This report for the International Energy Agency (IEA) made by Task 10 of the Photovoltaic Power Systems (PVPS) programme takes a look at urban photovoltaic electricity policies. The mission of the Photovoltaic Power Systems Programme is to enhance the international collaboration efforts which accelerate the development and deployment of photovoltaic solar energy as a significant and sustainable renewable energy option. The objective of Task 10 is stated as being to enhance the opportunities for wide-scale, solution-oriented application of photovoltaics in the urban environment. The goal of the study presented was to evaluate a standardised basis for urban policies regarding photovoltaic integration in a set of cities in the countries participating in the IEA's Task 10, Urban Scale PV. The investigation was focused on three topics: the present state of the policies, the prospects for future policies fostering photovoltaic deployment and the prospects for future policies to cope with large-scale photovoltaic integration. The first section analyses the state of the policies; this analysis is then confirmed in section 2, which deals with present obstacles to PV deployment and solutions to overcome them. The third section investigates future prospects for PV deployment with the question of mastering large scale integration. The report concludes that cities could formulate urban solutions by developing integrated, specific provisions for PV deployment in their urban infrastructure planning.

Photovoltaics: The present presages the future

International Nuclear Information System (INIS)

Thornton, J.; Brown, L.

1992-01-01

This article is a technical assessment on photovoltaics and what effect new technology has on the ability of photovoltaics to compete in the utility market. The topics of the article include the solar resource, photovoltaic cells and systems, thick and thin film cells, the spherical cell, photovoltaic modules and systems, photovoltaic economics and utility applications, and technology transfer programs in the area of photovoltaic manufacturing

Hierarchical ultrathin alumina membrane for the fabrication of unique nanodot arrays

International Nuclear Information System (INIS)

Wang, Yuyang; Wang, Yi; Wang, Hailong; Wang, Xinnan; Cong, Ming; Xu, Weiqing; Xu, Shuping

2016-01-01

Ultrathin alumina membranes (UTAMs) as evaporation masks have been a powerful tool for the fabrication of high-density nanodot arrays and have received much attention in magnetic memory devices, photovoltaics, and nanoplasmonics. In this paper, we report the fabrication of a hierarchical ultrathin alumina membrane (HUTAM) with highly ordered submicro/nanoscale channels and its application as an evaporation mask for the realization of unique non-hexagonal nanodot arrays dependent on the geometrical features of the HUTAM. This is the first report of a UTAM with a hierarchical geometry, breaking the stereotype that only limited sets of nanopatterns can be realized using the UTAM method (with typical inter-pore distance of 100 nm). The fabrication of a HUTAM is discussed in detail. An improved, longer wet etching time than previously reported is found to effectively remove the barrier layer and widen the pores of a HUTAM. A growth sustainability issue brought about by pre-patterning is discussed. Spectral comparison was made to distinguish the UTAM nanodots and HUTAM nanodots. Our results can be an inspiration for more sophisticated applications of pre-patterned anodized aluminum oxide in photocatalysis, photovoltaics, and nanoplasmonics. (paper)

Cobalt selenide hollow nanorods array with exceptionally high electrocatalytic activity for high-efficiency quasi-solid-state dye-sensitized solar cells

Science.gov (United States)

Jin, Zhitong; Zhang, Meirong; Wang, Min; Feng, Chuanqi; Wang, Zhong-Sheng

2018-02-01

In quasi-solid-state dye-sensitized solar cells (QSDSSCs), electron transport through a random network of catalyst in the counter electrode (CE) and electrolyte diffusion therein are limited by the grain boundaries of catalyst particles, thus diminishing the electrocatalytic performance of CE and the corresponding photovoltaic performance of QSDSSCs. We demonstrate herein an ordered Co0.85Se hollow nanorods array film as the Pt-free CE of QSDSSCs. The Co0.85Se hollow nanorods array displays excellent electrocatalytic activity for the reduction of I3- in the quasi-solid-state electrolyte with extremely low charge transfer resistance at the CE/electrolyte interface, and the diffusion of redox species within the Co0.85Se hollow nanorods array CE is pretty fast. The QSDSSC device with the Co0.85Se hollow nanorods array CE produces much higher photovoltaic conversion efficiency (8.35%) than that (4.94%) with the Co0.85Se randomly packed nanorods CE, against the control device with the Pt CE (7.75%). Moreover, the QSDSSC device based on the Co0.85Se hollow nanorods array CE presents good long-term stability with only 4% drop of power conversion efficiency after 1086 h one-sun soaking.

Photovoltaic barometer

International Nuclear Information System (INIS)

Anon.

2011-01-01

The photovoltaic sector is continuing on track, just as the extent of solar energy's electricity-generating potential is dawning on the public mind. The annual global installation figure was up more than twofold in 2010 (rising from just short of 7000 MWp in 2009). It leapt to over 16000 MWp, bringing worldwide installed photovoltaic capacity close to 38000 MWp. The photovoltaic power generated in the European Union at the end of 2010 reached 22.5 TWh which means an additional capacity of 13023 MWp during 2010. Concerning the cumulated installed capacity, Germany and Spain rank first and second in the European Union with respectively 17370 MWp and 3808 MWp

Photovoltaic barometer

International Nuclear Information System (INIS)

2006-01-01

This annual evaluation is a synthesis of works published in 2006. Comparisons are presented between the wind power performances and European Commission White Paper and Biomass action plan objectives. The european Union photovoltaic market reached the limits of the sector supply capacity for the first time. Meanwhile the prospects of growth in the photovoltaic market are still just as good as before. Silicon producers have finally responded to the expectations of the photovoltaic industry by announcing new production capacities. These extensions led to massively investing in new production capacities, in phase with ever greater demand. This increase in demand remains, however dependent upon the energy policy. (A.L.B.)

Photovoltaic device and method

Science.gov (United States)

Cleereman, Robert J; Lesniak, Michael J; Keenihan, James R; Langmaid, Joe A; Gaston, Ryan; Eurich, Gerald K; Boven, Michelle L

2015-01-27

The present invention is premised upon an improved photovoltaic device ("PVD") and method of use, more particularly to an improved photovoltaic device with an integral locator and electrical terminal mechanism for transferring current to or from the improved photovoltaic device and the use as a system.

A photovoltaic-driven and energy-autonomous CMOS implantable sensor.

Science.gov (United States)

Ayazian, Sahar; Akhavan, Vahid A; Soenen, Eric; Hassibi, Arjang

2012-08-01

An energy-autonomous, photovoltaic (PV)-driven and MRI-compatible CMOS implantable sensor is presented. On-chip P+/N-well diode arrays are used as CMOS-compatible PV cells to harvest μW's of power from the light that penetrates into the tissue. In this 2.5 mm × 2.5 mm sub-μW integrated system, the in-vivo physiological signals are first measured by using a subthreshold ring oscillator-based sensor, the acquired data is then modulated into a frequency-shift keying (FSK) signal, and finally transmitted neuromorphically to the skin surface by using a pair of polarized electrodes.

Photovoltaic systems in agriculture

International Nuclear Information System (INIS)

Corba, Z.; Katic, V.; Milicevic, D.

2009-01-01

This paper presents the possibility of using one of the renewable energy resources in agriculture. Specifically, the paper shows the possibility of converting solar energy into electricity through photovoltaic panels. The paper includes the analysis of the energy potential of solar radiation in the AP Vojvodina (Serbia). The results of the analysis can be used for the design of photovoltaic energy systems. The amount of solar energy on the territory of the province is compared with the same data from some European countries, in order to obtain a clear picture of the possibilities of utilization of this type of renewable sources. Three examples of possible application of photovoltaic systems are presented. The first relates to the consumer who is away from the electric distribution network - photovoltaic system in island mode. The remaining two examples relate to the application of photovoltaic power sources in manufacturing plants, flowers or vegetables. Applying photovoltaic source of electrical energy to power pumps for irrigation is highlighted

Photovoltaic Product Directory and Buyers Guide

Energy Technology Data Exchange (ETDEWEB)

Watts, R.L.; Smith, S.A.; Dirks, J.A.; Mazzucchi, R.P.; Lee, V.E.

1984-04-01

The directory guide explains photovoltaic systems briefly and shows what products are available off-the-shelf. Information is given to assist in designing a photovoltaic system and on financial incentives. Help is given for determining if photovoltaic products can meet a particular buyer's needs, and information is provided on actual photovoltaic user's experiences. Detailed information is appended on various financial incentives available from state and federal governments, sources of additional information on photovoltaics, sources of various photovoltaic products, and a listing of addresses of photovoltaic products suppliers. (LEW)

Photovoltaic cell and array technology development for future unique NASA missions

Science.gov (United States)

Bailey, S.; Curtis, H.; Piszczor, M.; Surampudi, R.; Hamilton, T.; Rapp, D.; Stella, P.; Mardesich, N.; Mondt, J.; Bunker, R.;

Photovoltaics fundamentals, technology and practice

CERN Document Server

Mertens, Konrad

2013-01-01

Concise introduction to the basic principles of solar energy, photovoltaic systems, photovoltaic cells, photovoltaic measurement techniques, and grid connected systems, overviewing the potential of photovoltaic electricity for students and engineers new to the topic After a brief introduction to the topic of photovoltaics' history and the most important facts, Chapter 1 presents the subject of radiation, covering properties of solar radiation, radiation offer, and world energy consumption. Chapter 2 looks at the fundamentals of semiconductor physics. It discusses the build-up of semiconducto

Photovoltaic solar cell

Science.gov (United States)

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

2013-11-26

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

Modeling Photovoltaic Power

OpenAIRE

Mavromatakis, F.; Franghiadakis, Y.; Vignola, F.

2016-01-01

A robust and reliable model describing the power produced by a photovoltaic system is needed in order to be able to detect module failures, inverter malfunction, shadowing effects and other factors that may result to energy losses. In addition, a reliable model enables an investor to perform accurate estimates of the system energy production, payback times etc. The model utilizes the global irradiance reaching the plane of the photovoltaic modules since in almost all Photovoltaic (PV) facilit...

Fiscal 2000 achievement report. International demonstrative development of photovoltaic power generation system (Demonstrative study on grid-connected photovoltaic power generation system in Thailand); 2000 nendo seika hokokusho. Taiyoko hatsuden system kokusai kyodo jissho kaihatsu - Taiyoko hatsuden keitou renkei system jissho kenkyu (Tai)

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-09-01

A demonstrative study was conducted in Thailand for grasping the effect on small electricity grids when several photovoltaic power generation systems, including AC modules, are connected to the grid. In fiscal 2000, surveys and studies were conducted about the data of the local power system, where to install the demonstrative system, and how to install the same, which were necessary for working out a basic design for Libong Island newly designated as the site for the demonstrative system. It was then concluded that the demonstrative system be a grid-connected 100 kW-level photovoltaic system comprising one main photovoltaic power station (85 kW), photovoltaic power systems for school buildings (3-6 kW, three schools), and AC modules (110 W, 10 locations). The manufacture of solar cell modules, grid-connected power conditioners, and measuring devices were completed. Civil engineering work and construction were under way on the site, including the construction of a management building, installation of concrete bases for solar cell arrays, construction of fences surrounding the site, and so forth. (NEDO)

Photovoltaic solar energy. Proceedings; Photovoltaische Solarenergie. Tagungsband

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-07-01

and limits (Mike Meinhardt); (17) Washing with the sun - Direct consumption of locally generated PV current by means of directed load shift in private households (Georg Bopp); (18) Efficiency by synergy. Export initiative renewable energies (Berthold Breid); (19) Modular PV power supply in the Empire of the Midth (Michael Wollny); (20) Breakthrough to a new era of PV hybrid systems with the help of standardised components communication? (Michael Mueller); (21) New PV stand-alone supply for frequency variable loads (Wolfgang Hernschier); (22) Characterization of solar batteries in long-term investigations according IEC 61427 (Wolfgang Wiesner); (23) Professional PV plant configuration - the status quo of the PV prpgrams (Mike Zehner); (24) Simulating renewable power projects with greenius{sup Free} (Volker Quaschning); (25) Analysis of the effect of shade and equivalent circuit of PV modules with the simulation software ''Solar Pro'' (Yusuke Mataki); (26) From data sheet values to the system gain - on realistic modelling of small PV generators (Hans Georg Beyer); (27) Form follows function - follows form function? - Ineractions between building functions and photovoltaic (Wolfgang Willkomm); (28) Market chances and technology perspectives for the Swiss facade construction by means of building integrated PV systems (Reto Miloni); (29) Passiv solar office building BIOHAUS Paderborn - architectonic overview and a first energy balance (Willi Ernst, Ralf Zirkler); (30) Building integration and education in Austria (Gernot Becker); (31) Photovoltaic and light (Thomas Herzog); (32) 10 years of test experience with the certification of design of photovoltaic modules (Andreas Cox); (32) Large size solar cells and the IEC 61215 - New challenges for the module junction (Eckehard Hofmueller); (33) Limits of power output optimisation of PV arrays by pre-sorting of PV modules (Werner Herrmann); (34) Coloured and patterned CIS modules (Dieter Geyer); (35) Energy

Photovoltaic technology diffusion. Contact and interact

International Nuclear Information System (INIS)

Kruijsen, J.

1999-09-01

How can the diffusion of photovoltaic technologies be advanced? Photovoltaics convert light into electrical energy. They are environmentally friendly, reliable and have minimal maintenance requirements. Up to now, their introduction into the electricity market has been dominated by a technology push perspective. However, this has not yet resulted in a large-scale implementation. This thesis describes a network approach to advance photovoltaic diffusion and presents four guiding principles intended for the parties concerned: those who supply the photovoltaic technologies (e.g., developers of photovoltaic cells); those who integrate photovoltaic technologies into (new) product systems (e.g., engineering firms); the users of photovoltaic systems (e.g., housing corporations); and those who stimulate the use of photovoltaics (e.g., policymakers, subsidisers, branch organisations, financial institutes, and NGOs). refs

Solar energy: photovoltaics

International Nuclear Information System (INIS)

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

1994-01-01

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

Black GE based on crystalline/amorphous core/shell nanoneedle arrays

Science.gov (United States)

Javey, Ali; Chueh, Yu-Lun; Fan, Zhiyong

2014-03-04

Direct growth of black Ge on low-temperature substrates, including plastics and rubber is reported. The material is based on highly dense, crystalline/amorphous core/shell Ge nanoneedle arrays with ultrasharp tips (.about.4 nm) enabled by the Ni catalyzed vapor-solid-solid growth process. Ge nanoneedle arrays exhibit remarkable optical properties. Specifically, minimal optical reflectance (<1%) is observed, even for high angles of incidence (.about.75.degree.) and for relatively short nanoneedle lengths (.about.1 .mu.m). Furthermore, the material exhibits high optical absorption efficiency with an effective band gap of .about.1 eV. The reported black Ge can have important practical implications for efficient photovoltaic and photodetector applications on nonconventional substrates.

Concentrator Photovoltaics

CERN Document Server

Luque, Antonio L

2007-01-01

Photovoltaic solar-energy conversion is one of the most promising technologies for generating renewable energy, and conversion of concentrated sunlight can lead to reduced cost for solar electricity. In fact, photovoltaic conversion of concentrated sunlight insures an efficient and cost-effective sustainable power resource. This book gives an overview of all components, e.g. cells, concentrators, modules and systems, for systems of concentrator photovoltaics. The authors report on significant results related to design, technology, and applications, and also cover the fundamental physics and market considerations. Specific contributions include: theory and practice of sunlight concentrators; an overview of concentrator PV activities; a description of concentrator solar cells; design and technology of modules and systems; manufacturing aspects; and a market study.

A novel application for concentrator photovoltaic in the field of agriculture photovoltaics

Science.gov (United States)

Liu, Luqing; Guan, Chenggang; Zhang, Fangxin; Li, Ming; Lv, Hui; Liu, Yang; Yao, Peijun; Ingenhoff, Jan; Liu, Wen

2017-09-01

Agriculture photovoltaics is a trend setting area which has already led to a new industrial revolution. Shortage of land in some countries and desertification of land where regular solar panels are deployed are some of the major problems in the photovoltaic industry. Concentrator photovoltaics experienced a decline in applicability after the cost erosion of regular solar panels at the end of the last decade. We demonstrate a novel and unique application for concentrator photovoltaics tackling at a same time the issue of conventional photovoltaics preventing the land being used for agricultural purpose where ever solar panels are installed. We leverage the principle of diffractive and interference technology to split the sun light into transmitted wavelengths necessary for plant growth and reflected wavelengths useful for solar energy generation. The technology has been successfully implemented in field trials and sophisticated scientific studies have been undertaken to evaluate the suitability of this technology for competitive solar power generation and simultaneous high-quality plant growth. The average efficiency of the agriculture photovoltaic system has reached more than 8% and the average efficiency of the CPV system is 6.80%.

Photovoltaic Solar Energy

International Nuclear Information System (INIS)

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

1998-01-01

A short historical review of the technological advances; the current state and the perspectives of the materials for photovoltaic applications is made. Thereinafter, the general aspects of the physical principles and fundamental parameters that govern the operation of the solar cells are described. To way of the example, a methodology for the design and facilities size of a photovoltaic system is applied. Finally, the perspectives of photovoltaic solar energy in relationship to the market and political of development are mentioned

Environmental Assessment for the Solar Photovoltaic Array at Eglin Air Force Base, Florida

Science.gov (United States)

2014-01-24

fire hazard to solar panel array. ● Where applicable, reduce erosion using rough grade slopes or terrace slopes. ● Identify areas of existing...method would entail the installation of numerous smaller solar PV systems on the roofs of various buildings on the base. This alternative was...panel array.  Where applicable, reduce erosion using rough grade slopes or terrace slopes.  Identify areas of existing vegetation that the proponent

Photovoltaic roof construction

Energy Technology Data Exchange (ETDEWEB)

Hawley, W.W.

1980-02-26

In a batten-seam roof construction employing at least one photovoltaic cell module, the electrical conduits employed with the at least one photovoltaic cell module are disposed primarily under the battens of the roof.

Organic Semiconductor Photovoltaics

Science.gov (United States)

Sariciftci, Niyazi Serdar

2005-03-01

Recent developments on organic photovoltaic elements are reviewed. Semiconducting conjugated polymers and molecules as well as nanocrystalline inorganic semiconductors are used in composite thin films. The photophysics of such photoactive devices is based on the photoinduced charge transfer from donor type semiconducting molecules onto acceptor type molecules such as Buckminsterfullerene, C60 and/or nanoparticles. Similar to the first steps in natural photosynthesis, this photoinduced electron transfer leads to a number of potentially interesting applications which include sensitization of the photoconductivity and photovoltaic phenomena. Examples of photovoltaic architectures are discussed with their potential in terrestrial solar energy conversion. Several materials are introduced and discussed for their photovoltaic activities. Furthermore, nanomorphology has been investigated with AFM, SEM and TEM. The morphology/property relationship for a given photoactive system is found to be a major effect.

Tracking the global maximum power point of PV arrays under partial shading conditions

Science.gov (United States)

Fennich, Meryem

This thesis presents the theoretical and simulation studies of the global maximum power point tracking (MPPT) for photovoltaic systems under partial shading. The main goal is to track the maximum power point of the photovoltaic module so that the maximum possible power can be extracted from the photovoltaic panels. When several panels are connected in series with some of them shaded partially either due to clouds or shadows from neighboring buildings, several local maxima appear in the power vs. voltage curve. A power increment based MPPT algorithm is effective in identifying the global maximum from the several local maxima. Several existing MPPT algorithms are explored and the state-of-the-art power increment method is simulated and tested for various partial shading conditions. The current-voltage and power-voltage characteristics of the PV model are studied under different partial shading conditions, along with five different cases demonstrating how the MPPT algorithm performs when shading switches from one state to another. Each case is supplemented with simulation results. The method of tracking the Global MPP is based on controlling the DC-DC converter connected to the output of the PV array. A complete system simulation including the PV array, the direct current to direct current (DC-DC) converter and the MPPT is presented and tested using MATLAB software. The simulation results show that the MPPT algorithm works very well with the buck converter, while the boost converter needs further changes and implementation.

Photovoltaic product directory and buyers guide

Energy Technology Data Exchange (ETDEWEB)

Watts, R.L.; Smith, S.A.; Mazzucchi, R.P.

1981-06-01

Basic information on photovoltaic conversion technology is provided for those unfamiliar with the field. Various types of photovoltaic products and systems currently available off-the-shelf are described. These include products without batteries, battery chargers, power packages, home electric systems, and partial systems. Procedures are given for designing a photovoltaic system from scratch. A few custom photovoltaic systems are described, and a list is compiled of photovoltaic firms which can provide custom systems. Guidance is offered for deciding whether or not to use photovoltaic products. A variety of installations are described and their performance is appraised by the owners. Information is given on various financial incentives available from state and federal governments. Sources of additional information on photovoltaics are listed. A matrix is provided indicating the sources of various types of photovoltaic products. The addresses of suppliers are listed. (LEW)

Characteristics of heat transfer and fluid flow in a channel with single-row plates array oblique to flow direction for photovoltaic/thermal system

Energy Technology Data Exchange (ETDEWEB)

Ali, Ahmed Hamza H. [Department of Energy Resources and Environmental Engineering, Egypt-Japan University of Science and Technology (E-JUST), P.O. Box 179, New Borg El-Arab City, Alexandria 21934 (Egypt); Ahmed, Mahmoud; Youssef, M.S. [Department of Mechanical Engineering, Faculty of Engineering, Assiut University, Assiut 71516 (Egypt)

2010-09-15

This study has been carried out to investigate the characteristics of convective heat transfer and fluid flow for a single row of oblique plates array to the flow direction inside a channel. The flow inside the channel is laminar and the plates array have spanwise distance between the plates and heated by radiation. This configuration has been designed to be used for Photovoltaic/Thermal system (PV/T) applications. The theoretical results are validated with measured values, and a good agreement prevailed. The results show that an increase in the plate oblique angle ({gamma}) in the range from 0 to 15 degrees, leads to an increase in the Nusselt number (Nu) up to a maximum value and then decreases. The oblique angle at the maximum value of Nu depends on the flow Reynolds Number (Re), and (l{sub w}/l{sub pl}), where (l{sub w}/l{sub pl}) is defined as the ratio of the plates' spacing at zero oblique angle to the plate length. Furthermore, increasing (l{sub w}/l{sub pl}) results in a significant increase in the heat transfer coefficient depending on the values of Re, and plate oblique angle ({gamma}). In addition, increasing ({gamma}) from 0 to 15 degrees results in a decrease in the friction factor up to a certain value, after which the friction value approaches a constant value depending on Re value and (l{sub w}/l{sub pl}). It was found that for any value of the plate oblique angle ({gamma}), the friction factor decreases with the increase of the values of (l{sub w}/l{sub pl}) and Re, respectively. (author)

Fiscal 1998 New Sunshine Program achievement report. Development for practical application of photovoltaic system - Research and development of photovoltaic system evaluation technology (Research and development of system evaluation technology); 1998 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Taiyoko hatsuden system hyoka gijutsu no kenkyu kaihatsu (system hyoka gijutsu no kenkyu kaihatsu)

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-01

In relation with several types of standard photovoltaic power generation systems expected to be put to practical use, design parameters are quantified, databases are utilized, and simulation technologies are developed, while collecting data from test facilities constructed to simulate them, for the development of evaluation techniques indispensable for the efficient improvement of photovoltaic power generation systems. In fiscal 1998, data were collected from verification test facilities and residential photovoltaic systems sited across Japan. The collected data were subjected to analysis and simulation, by which correction factors were calculated for smudge, spectral response, incident radiation, and temperature. Furthermore, load matching factors and storage battery contribution rates were calculated by simulation for the stand-alone photovoltaic systems sited in five Japanese cities, each comprising an array, storage battery, charge/discharge controller, DC-DC converter, and a load. Reference is also made to a survey of trends of technology development. (NEDO)

Photovoltaic power generation system free of bypass diodes

Science.gov (United States)

Lentine, Anthony L.; Okandan, Murat; Nielson, Gregory N.

2015-07-28

A photovoltaic power generation system that includes a solar panel that is free of bypass diodes is described herein. The solar panel includes a plurality of photovoltaic sub-modules, wherein at least two of photovoltaic sub-modules in the plurality of photovoltaic sub-modules are electrically connected in parallel. A photovoltaic sub-module includes a plurality of groups of electrically connected photovoltaic cells, wherein at least two of the groups are electrically connected in series. A photovoltaic group includes a plurality of strings of photovoltaic cells, wherein a string of photovoltaic cells comprises a plurality of photovoltaic cells electrically connected in series. The strings of photovoltaic cells are electrically connected in parallel, and the photovoltaic cells are microsystem-enabled photovoltaic cells.

Photovoltaics in the Department of Defense

International Nuclear Information System (INIS)

Chapman, R.N.

1997-01-01

This paper documents the history of photovoltaic use within the Department of Defense leading up to the installation of 2.1 MW of photovoltaics underway today. This history describes the evolution of the Department of Defense's Tri-Service Photovoltaic Review Committee and the committee's strategic plan to realize photovoltaic's full potential through outreach, conditioning of the federal procurement system, and specific project development. The Photovoltaic Review Committee estimates photovoltaic's potential at nearly 4,000 MW, of which about 700 MW are considered to be cost-effective at today's prices. The paper describes photovoltaic's potential within the Department of Defense, the status and features of the 2.1-MW worth of photovoltaic systems under installation, and how these systems are selected and implemented. The paper also documents support provided to the Department of Defense by the Department of Energy dating back to the late 70s. copyright 1997 American Institute of Physics

US photovoltaic patents: 1991--1993

Energy Technology Data Exchange (ETDEWEB)

Pohle, L

1995-03-01

This document contains US patents on terrestrial photovoltaic (PV) power applications, including systems, components, and materials as well as manufacturing and support functions. The patent entries in this document were issued from 1991 to 1993. The entries were located by searching USPA, the database of the US Patent Office. The final search retrieved all patents under the class ``Batteries, Thermoelectric and Photoelectric`` and the subclasses ``Photoelectric,`` ``Testing,`` and ``Applications.`` The search also located patents that contained the words ``photovoltaic(s)`` or ``solar cell(s)`` and their derivatives. After the initial list was compiled, most of the patents on the following subjects were excluded: space photovoltaic technology, use of the photovoltaic effect for detectors, and subjects only peripherally concerned with photovoltaic. Some patents on these three subjects were included when ft appeared that those inventions might be of use in terrestrial PV power technologies.

Intermediate Photovoltaic System Application Experiment operational performance: executive summary. Volume for Beverly High School, Beverly, MA

Energy Technology Data Exchange (ETDEWEB)

1981-09-01

For the momth of July 1981, performance data are given for a grid-connected 100 kW photovoltaic flat panel power system at a high school in Massachusetts. The total electrical energy produced solar energy incident on the solar cells, array and system efficiency, capacity factor and insolation are given for the month and the daily energy production and incident solar energy are graphed. (LEW)

Simplified Method for Modeling the Impact of Arbitrary Partial Shading Conditions on PV Array Performance: Preprint

Energy Technology Data Exchange (ETDEWEB)

MacAlpine, Sara; Deline, Chris

2015-09-15

It is often difficult to model the effects of partial shading conditions on PV array performance, as shade losses are nonlinear and depend heavily on a system's particular configuration. This work describes and implements a simple method for modeling shade loss: a database of shade impact results (loss percentages), generated using a validated, detailed simulation tool and encompassing a wide variety of shading scenarios. The database is intended to predict shading losses in crystalline silicon PV arrays and is accessed using basic inputs generally available in any PV simulation tool. Performance predictions using the database are within 1-2% of measured data for several partially shaded PV systems, and within 1% of those predicted by the full, detailed simulation tool on an annual basis. The shade loss database shows potential to considerably improve performance prediction for partially shaded PV systems.

PRODUCTION TECHNICS AT GRAPHIC DESIGN EDUCATION AND THE NECCESSITY OF PREPARATION KNOWLEDGE OF PRE-PRINTING

OpenAIRE

CEYLAN, İbrahim Gökhan

2015-01-01

It is neccessary to teach the knowledge of production technics and pre-printing preparations besides the knowledge of developing creativity and aesthetic concerns in order to educate the designers to fullfill the needs of the sector totally at graphic design education. The printed materials prepared by the graphic designer should be evaluated in proper criterias ıf the materials are to be printed. Graphic designers should have the knowledge of the required knowledge of the area in order to me...

Photovoltaic applications

International Nuclear Information System (INIS)

Sidrach, M.

1992-01-01

The most common terrestrial applications of photovoltaic plants are reviewed. Classification of applications can be done considering end-use sectors and load profiles (consumption demand). For those systems with direct coupling the working point is determined by the intersection of the load line with the I-V curve Design guidelines are provided for photovoltaic systems. This lecture focusses on the distribution system and safeguards

Thin film photovoltaic panel and method

Science.gov (United States)

Ackerman, Bruce; Albright, Scot P.; Jordan, John F.

1991-06-11

A thin film photovoltaic panel includes a backcap for protecting the active components of the photovoltaic cells from adverse environmental elements. A spacing between the backcap and a top electrode layer is preferably filled with a desiccant to further reduce water vapor contamination of the environment surrounding the photovoltaic cells. The contamination of the spacing between the backcap and the cells may be further reduced by passing a selected gas through the spacing subsequent to sealing the backcap to the base of the photovoltaic panels, and once purged this spacing may be filled with an inert gas. The techniques of the present invention are preferably applied to thin film photovoltaic panels each formed from a plurality of photovoltaic cells arranged on a vitreous substrate. The stability of photovoltaic conversion efficiency remains relatively high during the life of the photovoltaic panel, and the cost of manufacturing highly efficient panels with such improved stability is significantly reduced.

Photovoltaic engineering handbook

Energy Technology Data Exchange (ETDEWEB)

Lasnier, F; Ang, T G [Asian Institute of Technolgoy, Bangkok (TH)

1990-01-01

The Photovoltaic Engineering Handbook is a comprehensive 'nuts and bolts' guide to photovoltaic technology and systems engineering aimed at engineers and designers in the field. It is the first book to look closely at the practical problems involved in evaluating and setting up a PV power system. The authors' comprehensive insight into the different procedures and decisions that a designer needs to make. The book is unique in its coverage and the technical information is presented in a concise and simple way to enable engineers from a wide range of backgrounds to initiate, assess, analyse and design a PV system. Energy planners making decisions on the most appropriate system for specific needs will also benefit from reading this book. Topics covered include technological processes, including solar cell technology, the photovoltaic generator, photovoltaic systems engineering; characterization and testing methods, sizing procedure; economic analysis and instrumentation. (author).

Periodic Arrays of Film-Coupled Cubic Nanoantennas as Tunable Plasmonic Metasurfaces

Directory of Open Access Journals (Sweden)

Vassilios Yannopapas

2015-03-01

Full Text Available We show theoretically that a two-dimensional periodic array of metallic nanocubes in close proximity to a metallic film acts as a metasurface with tunable absorbance. The presence of a metallic film underneath the array of plasmonic nanocubes leads to an impedance matched plasmonic metasurface enhancing up to 4 times the absorbance of incident radiation, in the spectral region below 500 nm. The absorbance spectrum is weakly dependent on the angle of incidence and state of polarization of incident light a functionality which can find application in thermo-photovoltaics. Our calculations are based on a hybrid layer-multiple-scattering (hLMS method based on a discrete-dipole approximation (DDA/T-matrix point matching method.

Solar Photovoltaic Cells.

Science.gov (United States)

Mickey, Charles D.

1981-01-01

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

Can photovoltaic replace nuclear?

International Nuclear Information System (INIS)

2017-01-01

As the French law on energy transition for a green growth predicts that one third of nuclear energy production is to be replaced by renewable energies (wind and solar) by 2025, and while the ADEME proposes a 100 per cent renewable scenario for 2050, this paper proposes a brief analysis of the replacement of nuclear energy by solar photovoltaic energy. It presents and discusses some characteristics of photovoltaic production: production level during a typical day for each month (a noticeable lower production in December), evolution of monthly production during a year, evolution of the rate between nuclear and photovoltaic production. A cost assessment is then proposed for energy storage and for energy production, and a minimum cost of replacement of nuclear by photovoltaic is assessed. The seasonal effect is outlined, as well as the latitude effect. Finally, the authors outline the huge cost of such a replacement, and consider that public support to new photovoltaic installations without an at least daily storage mean should be cancelled

Organic photovoltaics. Technology and market

International Nuclear Information System (INIS)

Brabec, Christoph J.

2004-01-01

Organic photovoltaics has come into the international research focus during the past three years. Up to now main efforts have focused on the improvement of the solar conversion efficiency, and in recent efforts 5% white light efficiencies on the device level have been realized. Despite this in comparison to inorganic technologies low efficiency, organic photovoltaics is evaluated as one of the future key technologies opening up completely new applications and markets for photovoltaics. The key property which makes organic photovoltaics so attractive is the potential of reel to reel processing on low cost substrates with standard coating and printing processes. In this contribution we discuss the economical and technical production aspects for organic photovoltaics

Models used to assess the performance of photovoltaic systems.

Energy Technology Data Exchange (ETDEWEB)

Stein, Joshua S.; Klise, Geoffrey T.

2009-12-01

This report documents the various photovoltaic (PV) performance models and software developed and utilized by researchers at Sandia National Laboratories (SNL) in support of the Photovoltaics and Grid Integration Department. In addition to PV performance models, hybrid system and battery storage models are discussed. A hybrid system using other distributed sources and energy storage can help reduce the variability inherent in PV generation, and due to the complexity of combining multiple generation sources and system loads, these models are invaluable for system design and optimization. Energy storage plays an important role in reducing PV intermittency and battery storage models are used to understand the best configurations and technologies to store PV generated electricity. Other researcher's models used by SNL are discussed including some widely known models that incorporate algorithms developed at SNL. There are other models included in the discussion that are not used by or were not adopted from SNL research but may provide some benefit to researchers working on PV array performance, hybrid system models and energy storage. The paper is organized into three sections to describe the different software models as applied to photovoltaic performance, hybrid systems, and battery storage. For each model, there is a description which includes where to find the model, whether it is currently maintained and any references that may be available. Modeling improvements underway at SNL include quantifying the uncertainty of individual system components, the overall uncertainty in modeled vs. measured results and modeling large PV systems. SNL is also conducting research into the overall reliability of PV systems.

Roof Photovoltaic Test Facility

Data.gov (United States)

Federal Laboratory Consortium — In order to accurately predict the annual energy production of photovoltaic systems for any given geographical location, building orientation, and photovoltaic cell...

Test-to-Failure of Crystalline Silicon Modules: Preprint

Energy Technology Data Exchange (ETDEWEB)

Hacke, P.; Terwilliger, K.; Glick, S.; Trudell, D.; Bosco, N.; Johnston, S.; Kurtz, S. R.

2010-10-01

Accelerated lifetime testing of five crystalline silicon module designs was carried out according to the Terrestrial Photovoltaic Module Accelerated Test-to-Failure Protocol. This protocol compares the reliability of various module constructions on a quantitative basis. The modules under test are subdivided into three accelerated lifetime testing paths: 85..deg..C/85% relative humidity with system bias, thermal cycling between ?40..deg..C and 85..deg..C, and a path that alternates between damp heat and thermal cycling. The most severe stressor is damp heat with system bias applied to simulate the voltages that modules experience when connected in an array. Positive 600 V applied to the active layer with respect to the grounded module frame accelerates corrosion of the silver grid fingers and degrades the silicon nitride antireflective coating on the cells. Dark I-V curve fitting indicates increased series resistance and saturation current around the maximum power point; however, an improvement in junction recombination characteristics is obtained. Shunt paths and cell-metallization interface failures are seen developing in the silicon cells as determined by electroluminescence, thermal imaging, and I-V curves in the case of negative 600 V bias applied to the active layer. Ability to withstand electrolytic corrosion, moisture ingress, and ion drift under system voltage bias are differentiated.

Application of photovoltaic generating system to electric power in large ship; Taiyoko hatsuden system no ogata senpaku eno oyo ni kansuru kento

Energy Technology Data Exchange (ETDEWEB)

Katagi, T; Ogawa, S; Nishikawa, E; Hashimoto, T [Kobe University of Mercantile Marine, Kobe (Japan); Ishida, K

1996-10-27

This paper describes the design of electric power system in a ship with photovoltaic power generating system, to examine applicability of the photovoltaic power generating system to the inboard power source. It also discusses effectiveness of the system for sea environment. At first, the actual route of a car carrier, meteorological data, and quantity of power consumption were picked up from the deck logbook and engine logbook. Then, the installation area of photovoltaic arrays, the quantity of photovoltaic power generation derived from the quantity of solar radiation, and the capacities of batteries and inverters were calculated, to design the electric power system in the ship with photovoltaic power generation system. Moreover, the NOx and SOx emissions were compared between the present power system and the usual power system using diesel power generator, to discuss the effectiveness of the present system for sea environment. Consequently, it was found that the emission of NOx was reduced by about 33% and the emission of SOx was reduced by about 28% compared to the usual power system. The effectiveness for sea environment was confirmed. 9 refs., 5 figs., 4 tabs.

Annealing Effect on Photovoltaic Performance of CdSe Quantum-Dots-Sensitized TiO2 Nanorod Solar Cells

Directory of Open Access Journals (Sweden)

Yitan Li

2012-01-01

Full Text Available Large area rutile TiO2 nanorod arrays were grown on F:SnO2 (FTO conductive glass using a hydrothermal method at low temperature. CdSe quantum dots (QDs were deposited onto single-crystalline TiO2 nanorod arrays by a chemical bath deposition (CBD method to make a photoelectrode. The solar cell was assembled using a CdSe-TiO2 nanostructure as the photoanode and polysulfide solution as the electrolyte. The annealing effect on optical and photovoltaic properties of CdSe quantum-dots-sensitized TiO2 nanorod solar cells was studied systematically. A significant change of the morphology and a regular red shift of band gap of CdSe nanoparticles were observed after annealing treatment. At the same time, an improved photovoltaic performance was obtained for quantum-dots-sensitized solar cell using the annealed CdSe-TiO2 nanostructure electrode. The power conversion efficiency improved from 0.59% to 1.45% as a consequence of the annealing effect. This improvement can be explained by considering the changes in the morphology, the crystalline quality, and the optical properties caused by annealing treatment.

US Photovoltaic Patents, 1988--1990

Energy Technology Data Exchange (ETDEWEB)

1991-12-01

This document contains US patents on terrestrial photovoltaic (PV) power applications, including systems, components, and materials, as well as manufacturing and support functions. The patent entries in this document were issued from 1988 through 1990. The entries were located by searching USPA, the data base of the US Patent Office. The final search retrieved all patents under the class ``Batteries, Thermoelectric and Photoelectric`` and the subclasses ``Photoelectric,`` ``Testing,`` and ``Applications.`` The search also located patents that contained the words ``photovoltaic(s)`` or ``solar cell(s)`` and their derivatives. A manual search of the patents in the Solar Energy Research Institute (SERI) patent file augmented the data base search. After the initial list was compiled, most of the patents on the following subjects were excluded: space photovoltaic technology, use of the photovoltaic effect for detectors and subjects only peripherally concerned with photovoltaics. Some patents on these three subjects were included when it appeared that those inventions might be of use in terrestrial PV power technologies.

Photovoltaic Wire, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — This Small Business Innovation Research Phase I project will investigate a new architecture for photovoltaic devices based on nanotechnology: photovoltaic wire. The...