Photovoltaic system derived data for determining the solar resource and for modeling the performance of other photovoltaic systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marion, Bill; Smith, Benjamin

Using performance data from some of the millions of installed photovoltaic (PV) modules with micro-inverters may afford the opportunity to provide ground-based solar resource data critical for developing PV projects. Here, a method was developed to back-solve for the direct normal irradiance (DNI) and the diffuse horizontal irradiance (DHI) from the measured ac power of south-facing PV module/micro-inverter systems. The method was validated using one year of irradiance and PV performance measurements for five PV systems, each with a different tilt/azimuth orientation, and located in Golden, Colorado. Compared to using a measured global horizontal irradiance for PV performance model input,more » using the back-solved values of DNI and DHI only increased the range of mean bias deviations from measured values by 0.6% for the modeled annual averages of the global tilt irradiance and ac power for the five PV systems. Correcting for angle-of-incidence effects is an important feature of the method to prevent underestimating the solar resource and for modeling the performance of PV systems with more dissimilar PV module orientations. The results for the method were also shown more favorable than the results when using an existing power projection method for estimating the ac power.« less

A novel anti-theft security system for photovoltaic modules

NASA Astrophysics Data System (ADS)

Khan, Wasif Ali; Lim, Boon-Han; Lai, An-Chow; Chong, Kok-Keong

2017-04-01

Solar farms are considered as easy target for thieves because of insufficient protection measures. Existing anti-theft approaches are based on system level and are not very preventive and efficient because these can be bypassed with some technical knowledge. Additionally, it is difficult for security guards to tackle them as robbers come in a form of a gang equipped with heavy weapons. In this paper, a low power auto shut-off and non-destructive system is proposed for photovoltaic (PV) modules to achieve better level of security at module level. In proposed method, the power generation function of the PV module will be shut-off internally and cannot be re-activated by unauthorized personnel, in the case of theft. Hence, the PV module will not be functional even sold to new customers. The system comprises of a microcontroller, a low power position sensor, a controllable semiconductor switch and a wireless reactive-able system. The anti-theft system is developed to be laminated inside PV module and will be interconnected with solar cells so it becomes difficult for thieves to temper. The position of PV module is retrieved by position sensor and stored in a microcontroller as an initial reference value. Microcontroller uses this stored reference value to control power supply of PV module via power switch. The stored reference value can be altered using wireless circuitry by following authentication protocol. It makes the system non-destructive as anti-theft function can be reset again by authorized personnel, if it is recovered after theft or moved for maintenance purposes. The research component includes the design of a position sensing circuit, an auto shut-off circuit, a reactive-able wireless security protection algorithm and finally the integration of the multiple circuits.

PV_LIB Toolbox v. 1.3

DOE Office of Scientific and Technical Information (OSTI.GOV)

2015-12-09

PV_LIB comprises a library of Matlab? code for modeling photovoltaic (PV) systems. Included are functions to compute solar position and to estimate irradiance in the PV system's plane of array, cell temperature, PV module electrical output, and conversion from DC to AC power. Also included are functions that aid in determining parameters for module performance models from module characterization testing. PV_LIB is open source code primarily intended for research and academic purposes. All algorithms are documented in openly available literature with the appropriate references included in comments within the code.

Design and simulation of maximum power point tracking (MPPT) system on solar module system using constant voltage (CV) method

NASA Astrophysics Data System (ADS)

Bhatara, Sevty Satria; Iskandar, Reza Fauzi; Kirom, M. Ramdlan

2016-02-01

Solar energy is one of renewable energy resource where needs a photovoltaic module to convert it into electrical energy. One of the problems on solar energy conversion is the process of battery charging. To improve efficiency of energy conversion, PV system needs another control method on battery charging called maximum power point tracking (MPPT). This paper report the study on charging optimation using constant voltage (CV) method. This method has a function of determining output voltage of the PV system on maximal condition, so PV system will always produce a maximal energy. A model represented a PV system with and without MPPT was developed using Simulink. PV system simulation showed a different outcome energy when different solar radiation and numbers of solar module were applied in the model. On the simulation of solar radiation 1000 W/m2, PV system with MPPT produces 252.66 Watt energy and PV system without MPPT produces 252.66 Watt energy. The larger the solar radiation, the greater the energy of PV modules was produced.

77 FR 73018 - Crystalline Silicon Photovoltaic Cells, Whether or Not Assembled Into Modules, From the People's...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-07

...., Ltd. (Chengdu) PV Module Co., Ltd. Canadian Solar International Canadian Solar 24.48 Limited..... Chint Solar (Zhejiang) 24.48 Co., Ltd. Suzhou Shenglong PV-Tech Co., Ltd Suzhou Shenglong PV-TECH 24.48.... Jetion Solar (China) Co., Ltd.... Jetion Solar (China) 24.48 Co., Ltd. Jiangsu Green Power PV Co., Ltd...

PV industry growth and module reliability in Thailand

NASA Astrophysics Data System (ADS)

Chenvidhya, Dhirayut; Seapan, Manit; Sangpongsanont, Yaowanee; Chenvidhya, Tanokkorn; Limsakul, Chamnan; Songprakorp, Roongrojana

2015-09-01

The PV applications in Thailand are now installed more than 1.2 GWp cumulatively. It is due to the National Renewable Energy Program and its targets. In the latest Alternative Energy Development Plan (AEDP), the PV electricity production target has increased from 2 GWp to 3 GWp. With this rapid growth, customers and manufacturers seek for module standard testing. So far over one thousands of PV modules per annum have been tested since 2012. The normal tests include type approval test according to TIS standard, acceptance test and testing for local standard development. For type test, the most module failure was found during damp heat test. For annual evaluation test, the power degradation and delamination of power was found between 0 to 6 percent from its nameplate after deployment of 0 to 5 years in the field. For thin-film module, the degradation and delamination was found in range of 0 to 13 percent (about 5 percent on average) from its nameplate for the modules in operation with less than 5 years. However, for the PV modules at the reference site on campus operated for 12 years, the power degradation was ranging from 10 to 15 percent. Therefore, a long term performance assessment needs to be considered to ensure the system reliability.

Modular Cascaded H-Bridge Multilevel PV Inverter with Distributed MPPT for Grid-Connected Applications

DOE PAGES

Xiao, Bailu; Hang, Lijun; Mei, Jun; ...

2014-09-04

This paper presents a modular cascaded H-bridge multilevel photovoltaic (PV) inverter for single- or three-phase grid-connected applications. The modular cascaded multilevel topology helps to improve the efficiency and flexibility of PV systems. To realize better utilization of PV modules and maximize the solar energy extraction, a distributed maximum power point tracking (MPPT) control scheme is applied to both single-phase and three-phase multilevel inverters, which allows the independent control of each dc-link voltage. For three-phase grid-connected applications, PV mismatches may introduce unbalanced supplied power, leading to unbalanced grid current. To solve this issue, a control scheme with modulation compensation is alsomore » proposed. An experimental three-phase 7-level cascaded H-bridge inverter has been built utilizing 9 H-bridge modules (3 modules per phase). Each H-bridge module is connected to a 185 W solar panel. Simulation and experimental results are presented to verify the feasibility of the proposed approach.« less

Maximum Power Point tracking charge controllers for telecom applications -- Analysis and economics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wills, R.H.

Simple charge controllers connect photovoltaic modules directly to the battery bank resulting in a significant power loss if the battery bank voltage differs greatly from the PV Maximum Power Point (MPP) voltage. Recent modeling work at AES has shown that dc-dc converter type MPP tracking charge controllers can deliver more than 30% more energy from PV modules to the battery when the PV modules are cool and the battery state of charge is low--this is typically both the worst case condition (i.e., winter) and also the design condition that determines the PV array size. Economic modeling, based on typical telecommore » system installed costs shows benefits of more than $3/Wp for MPPT over conventional charge controllers in this application--a value that greatly exceeds the additional cost of the dc-dc converter.« less

Long-term performance analysis of CIGS thin-film PV modules

NASA Astrophysics Data System (ADS)

Dhere, Neelkanth G.; Kaul, Ashwani; Pethe, Shirish A.

2011-09-01

Current accelerated qualification tests of photovoltaic (PV) modules mostly assist in avoiding infant mortality but can neither duplicate changes occurring in the field nor can predict useful lifetime. Therefore, outdoor monitoring of fielddeployed thin-film PV modules was undertaken at FSEC with goals of assessing their performance in hot and humid climate under high system voltage operation and to correlate the PV performance with the meteorological parameters. Significant and comparable degradation rate of -5.13% and -4.5% per year was found by PV USA type regression analysis for the positive and negative strings respectively of 40W glass-to-glass CIGS thin-film PV modules in the hot and humid climate of Florida. With the current-voltage measurements it was found that the performance degradation within the PV array was mainly due to a few (8-12%) modules having a substantially high degradation. The remaining modules within the array continued to show reasonable performance (>96% of the rated power after ~ 4years).

LCP- LIFETIME COST AND PERFORMANCE MODEL FOR DISTRIBUTED PHOTOVOLTAIC SYSTEMS

NASA Technical Reports Server (NTRS)

Borden, C. S.

1994-01-01

The Lifetime Cost and Performance (LCP) Model was developed to assist in the assessment of Photovoltaic (PV) system design options. LCP is a simulation of the performance, cost, and revenue streams associated with distributed PV power systems. LCP provides the user with substantial flexibility in specifying the technical and economic environment of the PV application. User-specified input parameters are available to describe PV system characteristics, site climatic conditions, utility purchase and sellback rate structures, discount and escalation rates, construction timing, and lifetime of the system. Such details as PV array orientation and tilt angle, PV module and balance-of-system performance attributes, and the mode of utility interconnection are user-specified. LCP assumes that the distributed PV system is utility grid interactive without dedicated electrical storage. In combination with a suitable economic model, LCP can provide an estimate of the expected net present worth of a PV system to the owner, as compared to electricity purchased from a utility grid. Similarly, LCP might be used to perform sensitivity analyses to identify those PV system parameters having significant impact on net worth. The user describes the PV system configuration to LCP via the basic electrical components. The module is the smallest entity in the PV system which is modeled. A PV module is defined in the simulation by its short circuit current, which varies over the system lifetime due to degradation and failure. Modules are wired in series to form a branch circuit. Bypass diodes are allowed between modules in the branch circuits. Branch circuits are then connected in parallel to form a bus. A collection of buses is connected in parallel to form an increment to capacity of the system. By choosing the appropriate series-parallel wiring design, the user can specify the current, voltage, and reliability characteristics of the system. LCP simulation of system performance is site-specific and follows a three-step procedure. First the hourly power produced by the PV system is computed using a selected year's insolation and temperature profile. For this step it is assumed that there are no module failures or degradation. Next, the monthly simulation is performed involving a month to month progression through the lifetime of the system. In this step, the effects of degradation, failure, dirt accumulation and operations/maintenance efforts on PV system performance over time are used to compute the monthly power capability fraction. The resulting monthly power capability fractions are applied to the hourly power matrix from the first step, giving the anticipated hourly energy output over the lifetime of the system. PV system energy output is compared with the PV system owner's electricity demand for each hour. The amount of energy to be purchased from or sold to the utility grid is then determined. Monthly expenditures on the PV system and the purchase of electricity from the utility grid are also calculated. LCP generates output reports pertaining to the performance of the PV system, and system costs and revenues. The LCP model, written in SIMSCRIPT 2.5 for batch execution on an IBM 370 series computer, was developed in 1981.

Space Station Freedom electric power system availability study

NASA Technical Reports Server (NTRS)

Turnquist, Scott R.

1990-01-01

The results are detailed of follow-on availability analyses performed on the Space Station Freedom electric power system (EPS). The scope includes analyses of several EPS design variations, these are: the 4-photovoltaic (PV) module baseline EPS design, a 6-PV module EPS design, and a 3-solar dynamic module EPS design which included a 10 kW PV module. The analyses performed included: determining the discrete power levels that the EPS will operate at upon various component failures and the availability of each of these operating states; ranking EPS components by the relative contribution each component type gives to the power availability of the EPS; determining the availability impacts of including structural and long-life EPS components in the availability models used in the analyses; determining optimum sparing strategies, for storing space EPS components on-orbit, to maintain high average-power-capability with low lift-mass requirements; and analyses to determine the sensitivity of EPS-availability to uncertainties in the component reliability and maintainability data used.

High efficiency H6 single-phase transformerless grid-tied PV inverter with proposed modulation for reactive power generation

NASA Astrophysics Data System (ADS)

Almasoudi, Fahad M.; Alatawi, Khaled S.; Matin, Mohammad

2017-08-01

Implementation of transformerless inverters in PV grid-tied system offer great benefits such as high efficiency, light weight, low cost, etc. Most of the proposed transformerless inverters in literature are verified for only real power application. Currently, international standards such as VDE-AR-N 4105 has demanded that PV grid-tied inverters should have the ability of controlling a specific amount of reactive power. Generation of reactive power cannot be accomplished in single phase transformerless inverter topologies because the existing modulation techniques are not adopted for a freewheeling path in the negative power region. This paper enhances a previous high efficiency proposed H6 trnasformerless inverter with SiC MOSFETs and demonstrates new operating modes for the generation of reactive power. A proposed pulse width modulation (PWM) technique is applied to achieve bidirectional current flow through freewheeling state. A comparison of the proposed H6 transformerless inverter using SiC MOSFETs and Si MOSFTEs is presented in terms of power losses and efficiency. The results show that reactive power control is attained without adding any additional active devices or modification to the inverter structure. Also, the proposed modulation maintains a constant common mode voltage (CM) during every operating mode and has low leakage current. The performance of the proposed system verifies its effectiveness in the next generation PV system.

Design of A Grid Integrated PV System with MPPT Control and Voltage Oriented Controller using MATLAB/PLECES

NASA Astrophysics Data System (ADS)

Soreng, Bineeta; Behera, Pradyumna; Pradhan, Raseswari

2017-08-01

This paper presents model of a grid-integrated photovoltaic array with Maximum Power Point Tracker (MPPT) and voltage oriented controller. The MPPT of the PV array is usually an essential part of PV system as MPPT helps the operating point of the solar array to align its maximum power point. In this model, the MPPT along with a DC-DC converter lets a PV generator to produce continuous power, despite of the measurement conditions. The neutral-point-clamped converter (NPC) with a boost converter raises the voltage from the panels to the DC-link. An LCL-filter smoothens the current ripple caused by the PWM modulation of the grid-side inverter. In addition to the MPPT, the system has two more two controllers, such as voltage controller and a current controller. The voltage control has a PI controller to regulate the PV voltage to optimal level by controlling the amount of current injected into the boost stage. Here, the grid-side converter transfers the power from the DC-link into the grid and maintains the DC-link voltage. Three-phase PV inverters are used for off-grid or designed to create utility frequency AC. The PV system can be connected in series or parallel to get the desired output power. To justify the working of this model, the grid-integrated PV system has been designed in MATLAB/PLECS. The simulation shows the P-V curve of implemented PV Array consisting 4 X 20 modules, reactive, real power, grid voltage and current.

Solar photovoltaic charging of lithium-ion batteries

NASA Astrophysics Data System (ADS)

Gibson, Thomas L.; Kelly, Nelson A.

Solar photovoltaic (PV) charging of batteries was tested by using high efficiency crystalline and amorphous silicon PV modules to recharge lithium-ion battery modules. This testing was performed as a proof of concept for solar PV charging of batteries for electrically powered vehicles. The iron phosphate type lithium-ion batteries were safely charged to their maximum capacity and the thermal hazards associated with overcharging were avoided by the self-regulating design of the solar charging system. The solar energy to battery charge conversion efficiency reached 14.5%, including a PV system efficiency of nearly 15%, and a battery charging efficiency of approximately 100%. This high system efficiency was achieved by directly charging the battery from the PV system with no intervening electronics, and matching the PV maximum power point voltage to the battery charging voltage at the desired maximum state of charge for the battery. It is envisioned that individual homeowners could charge electric and extended-range electric vehicles from residential, roof-mounted solar arrays, and thus power their daily commuting with clean, renewable solar energy.

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

NASA Astrophysics Data System (ADS)

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.

Military Energy Alternatives Conference

DTIC Science & Technology

2012-03-08

Power Generation and Alternative Energy Branch US Army RDECOM CERDEC CP&ID Power Division Aberdeen Proving Ground, MD...Co-generation Applications •Tactical Mobile Power •Vehicle-mounted Auxiliary Power and Environmental Control •Energy Security for Base...Mobile Power (PM MEP / PM CP) Vehicle Power (PM Tactical Vehicle / PM HTV) Portable Solar Photovoltaic (PV) Modules and Mobile Hybrid PV Power Sources

The AC photovoltaic module is here!

NASA Astrophysics Data System (ADS)

Strong, Steven J.; Wohlgemuth, John H.; Wills, Robert H.

1997-02-01

This paper describes the design, development, and performance results of a large-area photovoltaic module whose electrical output is ac power suitable for direct connection to the utility grid. The large-area ac PV module features a dedicated, integrally mounted, high-efficiency dc-to-ac power inverter with a nominal output of 250 watts (STC) at 120 Vac, 60 H, that is fully compatible with utility power. The module's output is connected directly to the building's conventional ac distribution system without need for any dc wiring, string combiners, dc ground-fault protection or additional power-conditioning equipment. With its advantages, the ac photovoltaic module promises to become a universal building block for use in all utility-interactive PV systems. This paper discusses AC Module design aspects and utility interface issues (including islanding).

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

USDA-ARS?s Scientific Manuscript database

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 ...

Solar-powered unmanned aerial vehicles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reinhardt, K.C.; Lamp, T.R.; Geis, J.W.

1996-12-31

An analysis was performed to determine the impact of various power system components and mission requirements on the size of solar-powered high altitude long endurance (HALE)-type aircraft. The HALE unmanned aerial vehicle (UAV) has good potential for use in many military and civil applications. The primary power system components considered in this study were photovoltaic (PV) modules for power generation and regenerative fuel cells for energy storage. The impact of relevant component performance on UAV size and capability were considered; including PV module efficiency and mass, power electronics efficiency, and fuel cell specific energy. Mission parameters such as time ofmore » year, flight altitude, flight latitude, and payload mass and power were also varied to determine impact on UAV size. The aircraft analysis method used determines the required aircraft wing aspect ratio, wing area, and total mass based on maximum endurance or minimum required power calculations. The results indicate that the capacity of the energy storage system employed, fuel cells in this analysis, greatly impacts aircraft size, whereas the impact of PV module efficiency and mass is much less important. It was concluded that an energy storage specific energy (total system) of 250--500 Whr/kg is required to enable most useful missions, and that PV cells with efficiencies greater than {approximately} 12% are suitable for use.« less

Optimal design and operation of a photovoltaic-electrolyser system using particle swarm optimisation

NASA Astrophysics Data System (ADS)

Sayedin, Farid; Maroufmashat, Azadeh; Roshandel, Ramin; Khavas, Sourena Sattari

2016-07-01

In this study, hydrogen generation is maximised by optimising the size and the operating conditions of an electrolyser (EL) directly connected to a photovoltaic (PV) module at different irradiance. Due to the variations of maximum power points of the PV module during a year and the complexity of the system, a nonlinear approach is considered. A mathematical model has been developed to determine the performance of the PV/EL system. The optimisation methodology presented here is based on the particle swarm optimisation algorithm. By this method, for the given number of PV modules, the optimal sizeand operating condition of a PV/EL system areachieved. The approach can be applied for different sizes of PV systems, various ambient temperatures and different locations with various climaticconditions. The results show that for the given location and the PV system, the energy transfer efficiency of PV/EL system can reach up to 97.83%.

Practical design considerations for photovoltaic power station

NASA Astrophysics Data System (ADS)

Swanson, T. D.

Aspects of photovoltaic (PV) technology are discussed along with generic PV design considerations, taking into account the resource sunlight, PV modules and their reliability, questions of PV system design, the support structure subsystem, and a power conditioning unit subsystem. A description is presented of two recent projects which demonstrate the translation of an idea into actual working PV systems. A privately financed project in Denton, Maryland, went on line in early December, 1982, and began providing power to the local utility grid. It represents the first intermediate size, grid-connected, privately financed power station in the U.S. Based on firm quotes, the actual cost of this system is about $13/W peak. The other project, called the PV Breeder, is an energy independent facility which utilizes solar power to make new solar cells. It is also the first large industrial structure completely powered by the sun.

Power Management System Design for Solar-Powered UAS

DTIC Science & Technology

2015-12-01

PV cells would have their own MPPT modules, which would enable two major advantages. The first can be considered more important to land-based solar ...The efficiency of the PV array is represented by ηpv. R represents the solar irradiance, and θ represents the angle between the array and the sun...SYSTEM DESIGN FOR SOLAR -POWERED UAS by Robert T. Fauci III December 2015 Thesis Advisor: Alejandro Hernandez Co-Advisor: Kevin Jones

Study of 1 MW PV array at the Kennedy Space Center

NASA Astrophysics Data System (ADS)

Dhere, Neelkanth G.; Schneller, Eric; Martin, Wayne R.; Dhere, Ramesh G.

2016-09-01

FP and L has deployed a 1 MW c-Si in a fenced compound at the Kennedy Space Center. Two 500 kW inverters located in an elevated and air-conditioned enclosure convert direct current (DC) to alternating current (AC). The generated power, DC and AC voltages and currents are measured and recorded. Charts of variation of PV parameters are generated for analyses. The generated power is also tabulated and reported on periodic basis. Infrared and visual images of the array, sections of the array, and of individual modules from the front and back are recorded periodically. Any interruption of power generation are recorded. The dust and corrosion on screws and frame were observed in a few modules. The temperature of active area of module is higher than that of metallic support and frame probably because of conduction of the heat by the heavy metallic structure. The 1-MW PV array is operating normally without signs of excessive degradation except for collection of dust towards the bottom of a few modules. Since these modules were not washed periodically and any cleaning was by rain. Thus the collection of dust towards the bottom of modules can be understood and does not pose a serious problem. Corrosion on screws and frame were observed in a few modules. This study if continued over a long time, will serve to follow the behavior of this reasonable size PV Plant.

Energy production estimation for Kosh-Agach grid-tie photovoltaic power plant for different photovoltaic module types

NASA Astrophysics Data System (ADS)

Gabderakhmanova, T. S.; Kiseleva, S. V.; Frid, S. E.; Tarasenko, A. B.

2016-11-01

This paper is devoted to calculation of yearly energy production, demanded area and capital costs for first Russian 5 MW grid-tie photovoltaic (PV) plant in Altay Republic that is named Kosh-Agach. Simple linear calculation model, involving average solar radiation and temperature data, grid-tie inverter power-efficiency dependence and PV modules parameters is proposed. Monthly and yearly energy production, equipment costs and demanded area for PV plant are estimated for mono-, polycrystalline and amorphous modules. Calculation includes three types of initial radiation and temperature data—average day for every month from NASA SSE, average radiation and temperature for each day of the year from NASA POWER and typical meteorology year generated from average data for every month. The peculiarities for each type of initial data and their influence on results are discussed.

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

NASA Astrophysics Data System (ADS)

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 loss of 61% (from 100 kW to 39 kW) over 26+ years. Encapsulation browning and non-cell interconnect ribbon breakages were determined to be the primary causes for the power loss.

Review of the environmental effects of the Space Station Freedom photovoltaic power module

NASA Technical Reports Server (NTRS)

Nahra, Henry K.

1989-01-01

An overview is provided of the environment in the low Earth orbit (LEO), the interaction of this environment with the Photovoltaic (PV) Power system of the Space Station Freedom is reviewed, and the environmental programs are described that are designed to investigate the interactions of the LEO environment with the photovoltaic power system. Such programs will support and impact the design of the subsystems of the PV module in order to survive the design lifetime in the LEO natural and induced environment.

Effect of Thermoelectric Cooling (TEC) module and the water flow heatsink on Photovoltaic (PV) panel performance

NASA Astrophysics Data System (ADS)

Amelia, A. R.; Jusoh, MA; Shamira Idris, Ida

2017-11-01

Photovoltaic (PV) panel suffers in low conversion efficiency of the output performance affected by the elevated operating temperature of the PV panel. It is important to keep the PV panel to operate at low temperature. To address this issue, this paper proposes the cooling system using thermoelectric cooling (TEC) and water block heatsink for enhancing the PV panel output performance. These both types cooling system were designed located on the back side of the PV panel to cool down the operating temperature of the PV panel. To evaluate the function for the existing cooling systems, the experiment was subsequently performed for PV panel without and with different design of the cooling system in outdoor weather conditions. By comparing the experimental results, it is concluded that by the hybrid cooling system which combining TEC module and the water block heatsink could improve the output performance of the PV panel. By the reduction temperature of the PV panel by 16.04 %, the average output power of the PV panel has been boosted up from 8.59 W to 9.03 W. In short, the output power of the PV panel was enhanced by the reduction of the operating temperature of the PV panel.

ANN based Real-Time Estimation of Power Generation of Different PV Module Types

NASA Astrophysics Data System (ADS)

Syafaruddin; Karatepe, Engin; Hiyama, Takashi

Distributed generation is expected to become more important in the future generation system. Utilities need to find solutions that help manage resources more efficiently. Effective smart grid solutions have been experienced by using real-time data to help refine and pinpoint inefficiencies for maintaining secure and reliable operating conditions. This paper proposes the application of Artificial Neural Network (ANN) for the real-time estimation of the maximum power generation of PV modules of different technologies. An intelligent technique is necessary required in this case due to the relationship between the maximum power of PV modules and the open circuit voltage and temperature is nonlinear and can't be easily expressed by an analytical expression for each technology. The proposed ANN method is using input signals of open circuit voltage and cell temperature instead of irradiance and ambient temperature to determine the estimated maximum power generation of PV modules. It is important for the utility to have the capability to perform this estimation for optimal operating points and diagnostic purposes that may be an early indicator of a need for maintenance and optimal energy management. The proposed method is accurately verified through a developed real-time simulator on the daily basis of irradiance and cell temperature changes.

A hybrid life-cycle inventory for multi-crystalline silicon PV module manufacturing in China

NASA Astrophysics Data System (ADS)

Yao, Yuan; Chang, Yuan; Masanet, Eric

2014-11-01

China is the world’s largest manufacturer of multi-crystalline silicon photovoltaic (mc-Si PV) modules, which is a key enabling technology in the global transition to renewable electric power systems. This study presents a hybrid life-cycle inventory (LCI) of Chinese mc-Si PV modules, which fills a critical knowledge gap on the environmental implications of mc-Si PV module manufacturing in China. The hybrid LCI approach combines process-based LCI data for module and poly-silicon manufacturing plants with a 2007 China IO-LCI model for production of raw material and fuel inputs to estimate ‘cradle to gate’ primary energy use, water consumption, and major air pollutant emissions (carbon dioxide, methane, sulfur dioxide, nitrous oxide, and nitrogen oxides). Results suggest that mc-Si PV modules from China may come with higher environmental burdens that one might estimate if one were using LCI results for mc-Si PV modules manufactured elsewhere. These higher burdens can be reasonably explained by the efficiency differences in China’s poly-silicon manufacturing processes, the country’s dependence on highly polluting coal-fired electricity, and the expanded system boundaries associated with the hybrid LCI modeling framework. The results should be useful for establishing more conservative ranges on the potential ‘cradle to gate’ impacts of mc-Si PV module manufacturing for more robust LCAs of PV deployment scenarios.

Modeling the irradiance and temperature rependence of photovoltaic modules in PVsyst

DOE PAGES

Sauer, Kenneth J.; Roessler, Thomas; Hansen, Clifford W.

2014-11-10

In order to reliably simulate the energy yield of photovoltaic (PV) systems, it is necessary to have an accurate model of how the PV modules perform with respect to irradiance and cell temperature. Building on previous work that addresses the irradiance dependence, two approaches to fit the temperature dependence of module power in PVsyst have been developed and are applied here to recent multi-irradiance and -temperature data for a standard Yingli Solar PV module type. The results demonstrate that it is possible to match the measured irradiance and temperature dependence of PV modules in PVsyst. As a result, improvements inmore » energy yield prediction using the optimized models relative to the PVsyst standard model are considered significant for decisions about project financing.« less

Highly Automated Module Production Incorporating Advanced Light Management

DOE Office of Scientific and Technical Information (OSTI.GOV)

Perelli-Minetti, Michael; Roof, Kyle

2015-08-11

The objective was to enable a high volume, cost effective solution for increasing the amount of light captured by PV modules through utilization of an advanced Light Re-directing Film and to follow a phased approach to develop and implement this new technology in order to achieve an expected power gain of up to 12 watts per module. Full size PV modules were manufactured using a new Light Redirecting Film (LRF) material applied to two different areas of PV modules in order to increase the amount of light captured by the modules. One configuration involved applying thin strips of LRF filmmore » over the tabbing ribbon on the cells in order to redirect the light that is normally absorbed by the tabbing ribbon to the active areas of the cells. A second configuration involved applying thin strips of LRF film over the white spaces between cells within a module in order to capture some of the light that is normally reflected from the white areas back through the front glass of the modules. Significant power increases of 1.4% (3.9 watts) and 1.0% (3.2 watts), respectively, compared to standard PV modules were measured under standard test conditions. The performance of PV modules with LRF applied to the tabbing ribbon was modeled. The results showed that the power increase provided by LRF depended greatly on the angle of incident light with the optimum performance only occurring when the light was within a narrow range of being perpendicular to the solar module. The modeling showed that most of the performance gain would be lost when the angle of incident light was greater than 28 degrees off axis. This effect made the orientation of modules with LRF applied to tabbing ribbons very important as modules mounted in “portrait” mode were predicted to provide little to no power gain from LRF under real world conditions. Based on these results, modules with LRF on tabbing ribbons would have to be mounted in “landscape” mode to realize a performance advantage. In addition, modeling showed that under diffuse lighting conditions such as when the sky is overcast, there would be no significant performance advantage for modules with LRF. Modules were sent to an outside contractor to measure the power performance under different angles of incident light in order to validate the modeling results. The measured data agreed very well with the modeling predictions and showed that the power gain for modules with LRF applied to tabbing ribbons was completely lost at an angle of 25 degrees off of perpendicular. At even larger angles, the power was lower than standard modules. From 35 degrees to 55 degrees off axis, the power loss was about 1.4% or equal to the power gain at the optimum condition of perfectly on-axis light.« less

Performance analysis of ‘Perturb and Observe’ and ‘Incremental Conductance’ MPPT algorithms for PV system

NASA Astrophysics Data System (ADS)

Lodhi, Ehtisham; Lodhi, Zeeshan; Noman Shafqat, Rana; Chen, Fieda

2017-07-01

Photovoltaic (PV) system usually employed The Maximum power point tracking (MPPT) techniques for increasing its efficiency. The performance of the PV system perhaps boosts by controlling at its apex point of power, in this way maximal power can be given to load. The proficiency of a PV system usually depends upon irradiance, temperature and array architecture. PV array shows a non-linear style for V-I curve and maximal power point on V-P curve also varies with changing environmental conditions. MPPT methods grantees that a PV module is regulated at reference voltage and to produce entire usage of the maximal output power. This paper gives analysis between two widely employed Perturb and Observe (P&O) and Incremental Conductance (INC) MPPT techniques. Their performance is evaluated and compared through theoretical analysis and digital simulation on the basis of response time and efficiency under varying irradiance and temperature condition using Matlab/Simulink.

A grid-connected single-phase photovoltaic micro inverter

NASA Astrophysics Data System (ADS)

Wen, X. Y.; Lin, P. J.; Chen, Z. C.; Wu, L. J.; Cheng, S. Y.

2017-11-01

In this paper, the topology of a single-phase grid-connected photovoltaic (PV) micro-inverter is proposed. The PV micro-inverter consists of DC-DC stage with high voltage gain boost and DC-AC conversion stage. In the first stage, we apply the active clamp circuit and two voltage multipliers to achieve soft switching technology and high voltage gain. In addition, the flower pollination algorithm (FPA) is employed for the maximum power point tracking (MPPT) in the PV module in this stage. The second stage cascades a H-bridge inverter and LCL filter. To feed high quality sinusoidal power into the grid, the software phase lock, outer voltage loop and inner current loop control method are adopted as the control strategy. The performance of the proposed topology is tested by Matlab/Simulink. A PV module with maximum power 300W and maximum power point voltage 40V is applied as the input source. The simulation results indicate that the proposed topology and the control strategy are feasible.

Terrestrial photovoltaic collector technology trends

NASA Technical Reports Server (NTRS)

Shimada, K.; Costogue, E.

1984-01-01

Following the path of space PV collector development in its early stages, terrestrial PV technologies based upon single-crystal silicon have matured rapidly. Currently, terrestrial PV cells with efficiencies approaching space cell efficiencies are being fabricated into modules at a fraction of the space PV module cost. New materials, including CuInSe2 and amorphous silicon, are being developed for lowering the cost, and multijunction materials for achieving higher efficiency. Large grid-interactive, tracking flat-plate power systems and concentrator PV systems totaling about 10 MW, are already in operation. Collector technology development both flat-plate and concentrator, will continue under an extensive government and private industry partnership.

Chris Deline | NREL

Science.gov Websites

., Meydbray, J., Donovan, M., and Forrest, J. 2014. Photovoltaic Shading Testbed for Module-Level Power Renewable Energy Laboratory (NREL) in Golden, Colorado, in the photovoltaic (PV) performance and reliability performance and stabilization, mismatch and partial shading in PV systems, and distributed power electronics

MPPT Algorithm Development for Laser Powered Surveillance Camera Power Supply Unit

NASA Astrophysics Data System (ADS)

Zhang, Yungui; Dushantha Chaminda, P. R.; Zhao, Kun; Cheng, Lin; Jiang, Yi; Peng, Kai

2018-03-01

Photovoltaics (PV) cells, modules which are semiconducting materials, convert light energy into electricity. Operation of a PV cell requires 3 basic features. When the light is absorbed it generate pairs of electron holes or excitons. An external circuit carrier opposite types of electrons irrespective of the source (sunlight or LASER light). The PV arrays have photovoltaic effect and the PV cells are defined as a device which has electrical characteristics: such as current, voltage and resistance. It varies when exposed to light, that the power output is depend on direct Laser-light. In this paper Laser-light to electricity by direct conversion with the use of PV cells and its concept of Band gap Energy, Series Resistance, Conversion Efficiency and Maximum Power Point Tracking (MPPT) methods [1].

Scheme for predictive fault diagnosis in photo-voltaic modules using thermal imaging

NASA Astrophysics Data System (ADS)

Jaffery, Zainul Abdin; Dubey, Ashwani Kumar; Irshad; Haque, Ahteshamul

2017-06-01

Degradation of PV modules can cause excessive overheating which results in a reduced power output and eventually failure of solar panel. To maintain the long term reliability of solar modules and maximize the power output, faults in modules need to be diagnosed at an early stage. This paper provides a comprehensive algorithm for fault diagnosis in solar modules using infrared thermography. Infrared Thermography (IRT) is a reliable, non-destructive, fast and cost effective technique which is widely used to identify where and how faults occurred in an electrical installation. Infrared images were used for condition monitoring of solar modules and fuzzy logic have been used to incorporate intelligent classification of faults. An automatic approach has been suggested for fault detection, classification and analysis. IR images were acquired using an IR camera. To have an estimation of thermal condition of PV module, the faulty panel images were compared to a healthy PV module thermal image. A fuzzy rule-base was used to classify faults automatically. Maintenance actions have been advised based on type of faults.

Parameters Identification for Photovoltaic Module Based on an Improved Artificial Fish Swarm Algorithm

PubMed Central

Wang, Hong-Hua

2014-01-01

A precise mathematical model plays a pivotal role in the simulation, evaluation, and optimization of photovoltaic (PV) power systems. Different from the traditional linear model, the model of PV module has the features of nonlinearity and multiparameters. Since conventional methods are incapable of identifying the parameters of PV module, an excellent optimization algorithm is required. Artificial fish swarm algorithm (AFSA), originally inspired by the simulation of collective behavior of real fish swarms, is proposed to fast and accurately extract the parameters of PV module. In addition to the regular operation, a mutation operator (MO) is designed to enhance the searching performance of the algorithm. The feasibility of the proposed method is demonstrated by various parameters of PV module under different environmental conditions, and the testing results are compared with other studied methods in terms of final solutions and computational time. The simulation results show that the proposed method is capable of obtaining higher parameters identification precision. PMID:25243233

Data acquisition and PV module power production in upgraded TEP/AzRISE solar test yard

NASA Astrophysics Data System (ADS)

Bennett, Whit E.; Fishgold, Asher D.; Lai, Teh; Potter, Barrett G.; Simmons-Potter, Kelly

2017-08-01

The Tucson Electric Power (TEP)/University of Arizona AzRISE (Arizona Research Institute for Solar Energy) solar test yard is continuing efforts to improve standardization and data acquisition reliability throughout the facility. Data reliability is ensured through temperature-insensitive data acquisition devices with battery backups in the upgraded test yard. Software improvements allow for real-time analysis of collected data, while uploading to a web server. Sample data illustrates high fidelity monitoring of the burn-in period of a polycrystalline silicon photovoltaic module test string with no data failures over 365 days of data collection. In addition to improved DAQ systems, precision temperature monitoring has been implemented so that PV module backside temperatures are routinely obtained. Weather station data acquired at the test yard provides local ambient temperature, humidity, wind speed, and irradiance measurements that have been utilized to enable characterization of PV module performance over an extended test period

Microinverter Thermal Performance in the Real-World: Measurements and Modeling

PubMed Central

Hossain, Mohammad Akram; Xu, Yifan; Peshek, Timothy J.; Ji, Liang; Abramson, Alexis R.; French, Roger H.

2015-01-01

Real-world performance, durability and reliability of microinverters are critical concerns for microinverter-equipped photovoltaic systems. We conducted a data-driven study of the thermal performance of 24 new microinverters (Enphase M215) connected to 8 different brands of PV modules on dual-axis trackers at the Solar Durability and Lifetime Extension (SDLE) SunFarm at Case Western Reserve University, based on minute by minute power and thermal data from the microinverters and PV modules along with insolation and environmental data from July through October 2013. The analysis shows the strengths of the associations of microinverter temperature with ambient temperature, PV module temperature, irradiance and AC power of the PV systems. The importance of the covariates are rank ordered. A multiple regression model was developed and tested based on stable solar noon-time data, which gives both an overall function that predicts the temperature of microinverters under typical local conditions, and coefficients adjustments reecting refined prediction of the microinverter temperature connected to the 8 brands of PV modules in the study. The model allows for prediction of internal temperature for the Enphase M215 given similar climatic condition and can be expanded to predict microinverter temperature in fixed-rack and roof-top PV systems. This study is foundational in that similar models built on later stage data in the life of a device could reveal potential influencing factors in performance degradation. PMID:26147339

Multiple-Color-Generating Cu(In,Ga)(S,Se)2 Thin-Film Solar Cells via Dichroic Film Incorporation for Power-Generating Window Applications.

PubMed

Yoo, Gang Yeol; Jeong, Jae-Seung; Lee, Soyoung; Lee, Youngki; Yoon, Hee Chang; Chu, Van Ben; Park, Gi Soon; Hwang, Yun Jeong; Kim, Woong; Min, Byoung Koun; Do, Young Rag

2017-05-03

There are four prerequisites when applying all types of thin-film solar cells to power-generating window photovoltaics (PVs): high power-generation efficiency, longevity and high durability, semitransparency or partial-light transmittance, and colorful and aesthetic value. Solid-type thin-film Cu(In,Ga)S 2 (CIGS) or Cu(In,Ga)(S,Se) 2 (CIGSSe) PVs nearly meet the first two criteria, making them promising candidates for power-generating window applications if they can transmit light to some degree and generate color with good aesthetic value. In this study, the mechanical scribing process removes 10% of the window CIGSSe thin-film solar cell with vacant line patterns to provide a partial-light-transmitting CIGSSe PV module to meet the third requirement. The last concept of creating distinct colors could be met by the addition of reflectance colors of one-dimensional (1D) photonic crystal (PC) dichroic film on the black part of a partial-light-transmitting CIGSSe PV module. Beautiful violets and blues were created on the cover glass of a black CIGSSe PV module via the addition of 1D PC blue-mirror-yellow-pass dichroic film to improve the aesthetic value of the outside appearance. As a general result from the low external quantum efficiency (EQE) and absorption of CIGSSe PVs below a wavelength of 400 nm, the harvesting efficiency and short-circuit photocurrent of CIGSSe PVs were reduced by only ∼10% without reducing the open-circuit voltage (V OC ) because of the reduced overlap between the absorption spectrum of CIGSSe PV and the reflectance spectrum of the 1D PC blue-mirror-yellow-pass dichroic film. The combined technology of partial-vacancy-scribed CIGSSe PV modules and blue 1D PC dichroic film can provide a simple strategy to be applied to violet/blue power-generating window applications, as such a strategy can improve the transparency and aesthetic value without significantly sacrificing the harvesting efficiency of the CIGSSe PV modules.

Suitability of representative electrochemical energy storage technologies for ramp-rate control of photovoltaic power

NASA Astrophysics Data System (ADS)

Jiang, Yu; Fletcher, John; Burr, Patrick; Hall, Charles; Zheng, Bowen; Wang, Da-Wei; Ouyang, Zi; Lennon, Alison

2018-04-01

Photovoltaic (PV) systems can exhibit rapid variances in their power output due to irradiance changes which can destabilise an electricity grid. This paper presents a quantitative comparison of the suitability of different electrochemical energy storage system (ESS) technologies to provide ramp-rate control of power in PV systems. Our investigations show that, for PV systems ranging from residential rooftop systems to megawatt power systems, lithium-ion batteries with high energy densities (up to 600 Wh L-1) require the smallest power-normalised volumes to achieve the ramp rate limit of 10% min-1 with 100% compliance. As the system size increases, the ESS power-normalised volume requirements are significantly reduced due to aggregated power smoothing, with high power lithium-ion batteries becoming increasingly more favourable with increased PV system size. The possibility of module-level ramp-rate control is also introduced, and results show that achievement of a ramp rate of 10% min-1 with 100% compliance with typical junction box sizes will require ESS energy and power densities of 400 Wh L-1 and 2300 W L-1, respectively. While module-level ramp-rate control can reduce the impact of solar intermittence, the requirement is challenging, especially given the need for low cost and long cycle life.

Insolation-oriented model of photovoltaic module using Matlab/Simulink

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tsai, Huan-Liang

2010-07-15

This paper presents a novel model of photovoltaic (PV) module which is implemented and analyzed using Matlab/Simulink software package. Taking the effect of sunlight irradiance on the cell temperature, the proposed model takes ambient temperature as reference input and uses the solar insolation as a unique varying parameter. The cell temperature is then explicitly affected by the sunlight intensity. The output current and power characteristics are simulated and analyzed using the proposed PV model. The model verification has been confirmed through an experimental measurement. The impact of solar irradiation on cell temperature makes the output characteristic more practical. In addition,more » the insolation-oriented PV model enables the dynamics of PV power system to be analyzed and optimized more easily by applying the environmental parameters of ambient temperature and solar irradiance. (author)« less

NREL Research Team Wins R&D 100 Award | News | NREL

Science.gov Websites

performance PV modules for large-scale solar power plants, commercial and residential buildings, and off-grid Laboratory (NREL) and First Solar have been selected to receive a 2003 R&D 100 award from R&D Magazine for developing a new process for depositing semiconductor layers onto photovoltaic (PV) modules

Effects of dust accumulation and module cleaning on performance ratio of solar rooftop system and solar power plants

NASA Astrophysics Data System (ADS)

Sakarapunthip, Nattakarn; Chenvidhya, Dhirayut; Chuangchote, Surawut; Kirtikara, Krissanapong; Chenvidhya, Tanokkorn; Onreabroy, Wandee

2017-08-01

Thailand is an agricultural country, with rice, sugar, and cassava as the major export products. Production of rice, sugar cane, and cassava entails agricultural activities that give rise to significant airborne dusts. In this work, five photovoltaic (PV) units (one solar rooftop and four power plants) are selected for the study. From the study of dust accumulation on glass surface located near rice farms, it was found that opaque areas due to the deposition of dust are 11-14% after 1-2-week exposure. As a consequence, PV system performance is affected. Performance ratio was calculated to determine these effects. Overall results reveal that during the dry and hot seasons, dust deposition significantly affects the performance ratio. The performance ratio reduces by 1.6-3% for 1-month dust accumulation and reduces by 6-8% for 2-month dust accumulation. After cleaning the dust accumulated, the performance ratio greatly increases, resulting in the increase in the energy output by 10%. This increase provides economic and cost benefits of PV cleaning. The performance ratio is not significantly changed during the rainy season, which PV modules are relatively clean as the dust is washed away by rain. It was also found that most of the solar power plants in Thailand still rely on manual cleaning of PV modules with washing water followed by wiping. However, only one power plant, employs a machine for cleaning, resulting in lower cleaning costs.

Switching coordination of distributed dc-dc converters for highly efficient photovoltaic power plants

DOEpatents

Agamy, Mohammed; Elasser, Ahmed; Sabate, Juan Antonio; Galbraith, Anthony William; Harfman Todorovic, Maja

2014-09-09

A distributed photovoltaic (PV) power plant includes a plurality of distributed dc-dc converters. The dc-dc converters are configured to switch in coordination with one another such that at least one dc-dc converter transfers power to a common dc-bus based upon the total system power available from one or more corresponding strings of PV modules. Due to the coordinated switching of the dc-dc converters, each dc-dc converter transferring power to the common dc-bus continues to operate within its optimal efficiency range as well as to optimize the maximum power point tracking in order to increase the energy yield of the PV power plant.

Energy performance of semi-transparent PV modules for applications in buildings

NASA Astrophysics Data System (ADS)

Fung, Yu Yan

Owing to the increasing awareness on energy conservation and environmental protection, building-integrated photovoltaic (BIPV) has been developed rapidly in the past decade. A number of research studies have been conducted on the energy performance of BIPV systems. However, most of the previous studies focused on the systems that incorporated with opaque type PV modules, little attention has been devoted to semi-transparent type PV modules, which have been commonly integrated in modern architectures. This thesis aims at evaluating the energy performance of the semi-transparent BIPV modules, including heat gains to the indoor environment, power generation from the PV modules and daylight utilization. Solar radiation intensity on PV module's surfaces is an essential parameter for assessing energy performance of the PV modules. Different slope solar radiation models are analyzed and compared. The model that best suits Hong Kong situations is selected for the further development of the energy performance of the BIPV modules. The optimum orientation and tilted angle are determined in the analysis. In addition to the solar radiation models, a detailed investigation on the heat gain through the semi-transparent BIPV modules is carried out in this study. A one-dimensional transient heat transfer model, the SPVHG model, for evaluating the thermal performance of the semi-transparent BIPV modules is developed. The SPVHG model considers in detail the energy that is transmitted, absorbed and reflected in each element of the BIPV modules such as solar cells and glass layers. A computer program of the model is written accordingly. By applying the SPVHG model, the heat gain through the semi-transparent BIPV module of any thickness can be determined for any solar irradiance level. The annual performance can also be assessed by inputting annual weather data to the model. In order to verify the SPVHG model, laboratory tests have been carried out on semi-transparent BIPV modules. A well-insulated calorimeter box and an adjustable steady-state type solar simulator which can provide up to 1600 W/m2 have been used in the tests. Energy that transmitted through the semi-transparent BIPV modules and entered the calorimeter box was evaluated. It was found that the experimental results and the simulated results support each other. The SPVHG model is validated and can be used for further studies. Other than heat transfer, power production and the daylight utilization are also the vital parts in the energy performance assessment of the semi-transparent BIPV module for applications in building facades. Power generation models of both opaque and semi-transparent BIPV modules are investigated in this study. In order to test the validity of the power generation model, measurements on a BIPV system of an existing building are carried out. The measurement results reveal a good validity of the power generation model. Only a minor modification to the model is required. The daylight utilization is evaluated by using an indoor illuminance model. The model estimates the mean internal illuminance on the working plane of a room when there is both sunlight and skylight. Consequently, the power saving due to the daylight utilization can be determined. By using the SPVHG model together with the power generation model and the indoor illuminance model, the energy performance, in terms of electricity benefit, of building facades that incorporated with semi-transparent BIPV modules is evaluated. Different scenarios are studied by changing various parameters such as the window to wall ratios, thickness and efficiency of the solar cells. The results show that the solar cells within the semi-transparent BIPV modules significantly reduce the solar heat gain and thus reduce the power consumption of air-conditioning systems. Taking into account the impacts of PV electricity generation and daylight utilization, the optimum solar cell area ratio in the PV modules varies from 0.7 to 0.9 for different window-to-wall ratios of the building facade. The largest net electricity benefit of the BIPV facade under the simulation conditions is around 120 kWh/m 2. The SPVHG model developed in this study is a precise model for calculating the amount of heat gains through the semi-transparent BIPV modules. By considering also the power generation and daylight utilization, the electricity benefit of different BIPV facade configurations can be simulated. This information should help engineers predict the cooling load due to the BIPV facade and thus review their designs for energy efficiency optimization. On the whole, the results of this study provide valuable reference to local engineers, designers and professionals for efficient BIPV facade applications.

Method of monolithic module assembly

DOEpatents

Gee, James M.; Garrett, Stephen E.; Morgan, William P.; Worobey, Walter

1999-01-01

Methods for "monolithic module assembly" which translate many of the advantages of monolithic module construction of thin-film PV modules to wafered c-Si PV modules. Methods employ using back-contact solar cells positioned atop electrically conductive circuit elements affixed to a planar support so that a circuit capable of generating electric power is created. The modules are encapsulated using encapsulant materials such as EVA which are commonly used in photovoltaic module manufacture. The methods of the invention allow multiple cells to be electrically connected in a single encapsulation step rather than by sequential soldering which characterizes the currently used commercial practices.

Effects of different excitation waveforms on detection and characterisation of delamination in PV modules by active infrared thermography

NASA Astrophysics Data System (ADS)

Sinha, Archana; Gupta, Rajesh

2017-10-01

Delamination significantly affects the performance and reliability of photovoltaic (PV) modules. Recently, an active infrared thermography approach using step heating has been exploited for the detection and characterisation of delamination in PV modules. However, step heating takes longer observation time and causes overheating problems. This paper presents the effects of different thermal excitation waveforms namely rectangular, half-sine and short pulse, on the detection and characterisation of delamination in PV module by experiments and simulations. For simulation, a 3-dimensional electro-thermal model of heat conduction, based on resistance-capacitance network approach, has been exploited to study the variation in maximum thermal contrast and peak contrast time with the delamination thickness and heating parameters. Results show that the rectangular waveform provides better detection of delamination due to higher absolute contrast, while the half-sine waveform allows better characterisation of delamination in the PV modules with low-cost and low-power heat source. The high-energy short pulse enabled quick visualisation of delamination, but has limited practical implementation. The advantages and limitations of each waveform have been highlighted to assess the specific requirement for appropriate choice in the non-destructive thermographic inspection of delamination in PV modules at the manufacturing units or outdoor fields.

Flat-plate solar array project of the US Department of Energy's National Photovoltaics Program: Ten years of progress

NASA Technical Reports Server (NTRS)

Christensen, Elmer

1985-01-01

The Flat-Plate Solar Array (FSA) Project, a Government-sponsored photovoltaics project, was initiated in January 1975 (previously named the Low-Cost Silicon Solar Array Project) to stimulate the development of PV systems for widespread use. Its goal then was to develop PV modules with 10% efficiency, a 20-year lifetime, and a selling price of $0.50 per peak watt of generating capacity (1975 dollars). It was recognized that cost reduction of PV solar-cell and module manufacturing was the key achievement needed if PV power systems were to be economically competitive for large-scale terrestrial use.

Solar photovoltaic systems in the development of Papua New Guinea

NASA Astrophysics Data System (ADS)

Kinnell, G. H.

Geographic and demographic features of Papua New Guinea are summarized, together with current applications of photovoltaic (PV) systems. The PV systems displace the increasing costs of generating power from diesel and kerosene powered units. PV systems power air navigation aids for the extensive air transport used in the absence of a road system. Remote television and visual aid education is possible with PV modules. A total of 50 kW of PV power is presently implemented, with the bulk dedicated to microwave repeater stations, navigation aids, and radio and lighting supplies. A village pumping installation is in operation, as are office lighting and ventilation, house lighting, and construction camp lighting. Another 350 kW is planned for the next 10 yr to run medical supply refrigeration, and further growth is seen for coupling with government-developed village lighting kits that feature industrial reflectors.

Bifacial PV cell with reflector for stand-alone mast for sensor powering purposes

NASA Astrophysics Data System (ADS)

Jakobsen, Michael L.; Thorsteinsson, Sune; Poulsen, Peter B.; Riedel, N.; Rødder, Peter M.; Rødder, Kristin

2017-09-01

Reflectors to bifacial PV-cells are simulated and prototyped in this work. The aim is to optimize the reflector to specific latitudes, and particularly northern latitudes. Specifically, by using minimum semiconductor area the reflector must be able to deliver the electrical power required at the condition of minimum solar travel above the horizon, worst weather condition etc. We will test a bifacial PV-module with a retroreflector, and compare the output with simulations combined with local solar data.

Experiences of a grid connected solar array energy production

NASA Astrophysics Data System (ADS)

Hagymássy, Zoltán; Vántus, András

2015-04-01

Solar energy possibilities of Hungary are higher than in Central Europe generally. The Institute for Land Utilisation, Technology and Regional Development of the University of Debrecen installed a photovoltaic (PV) system. The PV system is structured into 3 subsystems (fields). The first subsystem has 24 pieces of Kyocera KC 120 W type modules, the second subsystem has 72 pieces of Siemens ST 40W, and the remaining has 72 pieces of Dunasolar DS 40W In order to be operable independently of each other three inverter modules (SB 2500) had been installed. The recorder can be connected directly to a desktop PC. Operating and meteorological dates are recorded by MS Excel every 15 minutes. The power plant is connected to a weather station, which contents a PT 100 type temperature and humidity combined measuring instrument, a CM 11 pyranometer, and a wind speed measuring instrument. The produced DC, and AC power, together with the produced energy are as well, and the efficiency can be determined for each used PV technology. The measured operating and meteorological dates are collected by Sunny Boy Control, produced by the SMA. The energy productions of the subsystems are measured continually and the subsystems are measured separately. As an expected, the produced energy of polycrystalline -Si PV module and monocrystalline -Si PV was higher than amorphous-Si PV module. It is well known that energy analysis is more suitable for energy balance when we design a system. The air temperature and the temperature of the panels and the global irradiation conditions were measured. In summertime the panel temperature reaches 60-80 degrees in a sunny day. The panel temperatures are in a spring sunny day approximately 30-40 degrees. It can be concluded that the global irradiation is a major impact feature to influence the amount of energy produced. The efficiency depends on several parameters (spectral distribution of the incoming light, temperature values, etc.). The energy efficiency of a PV system in general can be defined as the ratio of the output energy of the system to the input energy received on the photovoltaic surface. As an expected, the energy efficiencies of polycrystalline -Si PV module and monocrystalline -Si PV was higher than amorphous-Si PV module. Based on our study, in general it can be concluded that the energy efficiency is lower than theoretical.

Comparison of efficiency degradation in polycrystalline-Si and CdTe thin-film PV modules via accelerated lifecycle testing

NASA Astrophysics Data System (ADS)

Lai, T.; Potter, B. G.; Simmons-Potter, K.

2017-08-01

Thin-film solar cells normally have the shortest energy payback time due to their simpler mass-production process compared to polycrystalline-Si photovoltaic (PV) modules, despite the fact that crystalline-Si-based technology typically has a longer total lifetime and a higher initial power conversion efficiency. For both types of modules, significant aging occurs during the first two years of usage with slower long-term aging over the module lifetime. The PV lifetime and the return-on-investment for local PV system installations rely on long-term device performance. Understanding the efficiency degradation behavior under a given set of environmental conditions is, therefore, a primary goal for experimental research and economic analysis. In the present work, in-situ measurements of key electrical characteristics (J, V, Pmax, etc.) in polycrystalline-Si and CdTe thin-film PV modules have been analyzed. The modules were subjected to identical environmental conditions, representative of southern Arizona, in a full-scale, industrial-standard, environmental degradation chamber, equipped with a single-sun irradiance source, temperature, and humidity controls, and operating an accelerated lifecycle test (ALT) sequence. Initial results highlight differences in module performance with environmental conditions, including temperature de-rating effects, for the two technologies. Notably, the thin-film CdTe PV module was shown to be approximately 15% less sensitive to ambient temperature variation. After exposure to a seven-month equivalent compressed night-day weather cycling regimen the efficiency degradation rates of both PV technology types were obtained and will be discussed.

Protoflight photovoltaic power module system-level tests in the space power facility

NASA Technical Reports Server (NTRS)

Rivera, Juan C.; Kirch, Luke A.

1989-01-01

Work Package Four, which includes the NASA-Lewis and Rocketdyne, has selected an approach for the Space Station Freedom Photovoltaic (PV) Power Module flight certification that combines system level qualification and acceptance testing in the thermal vacuum environment: The protoflight vehicle approach. This approach maximizes ground test verification to assure system level performance and to minimize risk of on-orbit failures. The preliminary plans for system level thermal vacuum environmental testing of the protoflight PV Power Module in the NASA-Lewis Space Power Facility (SPF), are addressed. Details of the facility modifications to refurbish SPF, after 13 years of downtime, are briefly discussed. The results of an evaluation of the effectiveness of system level environmental testing in screening out incipient part and workmanship defects and unique failure modes are discussed. Preliminary test objectives, test hardware configurations, test support equipment, and operations are presented.

DSP-Based Hands-On Laboratory Experiments for Photovoltaic Power Systems

ERIC Educational Resources Information Center

Muoka, Polycarp I.; Haque, Md. Enamul; Gargoom, Ameen; Negnetvitsky, Michael

2015-01-01

This paper presents a new photovoltaic (PV) power systems laboratory module that was developed to experimentally reinforce students' understanding of design principles, operation, and control of photovoltaic power conversion systems. The laboratory module is project-based and is designed to support a renewable energy course. By using MATLAB…

Electronic Equipment Proposal to Improve the Photovoltaic Systems Efficiency

NASA Astrophysics Data System (ADS)

Flores-Mena, J. E.; Juárez Morán, L. A.; Díaz Reyes, J.

2011-05-01

This paper reports a new technique proposal to improve the photovoltaic systems. It was made to design and implement an electronic system that will detect, capture, and transfer the maximum power of the photovoltaic (PV) panel to optimize the supplied power of a solar panel. The electronic system works on base technical proposal of electrical sweeping of electric characteristics using capacitive impedance. The maximum power is transformed and the solar panel energy is sent to an automotive battery. This electronic system reduces the energy lost originated when the solar radiation level decreases or the PV panel temperature is increased. This electronic system tracks, captures, and stores the PV module's maximum power into a capacitor. After, a higher voltage level step-up circuit was designed to increase the voltage of the PV module's maximum power and then its current can be sent to a battery. The experimental results show that the developed electronic system has 95% efficiency. The measurement was made to 50 W, the electronic system works rightly with solar radiation rate from 100 to 1,000 W m - 2 and the PV panel temperature rate changed from 1 to 75°C. The main advantage of this electronic system compared with conventional methods is the elimination of microprocessors, computers, and sophisticated numerical approximations, and it does not need any small electrical signals to track the maximum power. The proposed method is simple, fast, and it is also cheaper.

Multifunctional microstructured polymer films for boosting solar power generation of silicon-based photovoltaic modules.

PubMed

Leem, Jung Woo; Choi, Minkyu; Yu, Jae Su

2015-02-04

We propose two-dimensional periodic conical micrograting structured (MGS) polymer films as a multifunctional layer (i.e., light harvesting and self-cleaning) at the surface of outer polyethylene terephthalate (PET) cover-substrates for boosting the solar power generation in silicon (Si)-based photovoltaic (PV) modules. The surface of ultraviolet-curable NOA63 MGS polymer films fabricated by the soft imprint lithography exhibits a hydrophobic property with water contact angle of ∼121° at no inclination and dynamic advancing/receding water contact angles of ∼132°/111° at the inclination angle of 40°, respectively, which can remove dust particles or contaminants on the surface of PV modules in real outdoor environments (i.e., self-cleaning). The NOA63 MGS film coated on the bare PET leads to the reduction of reflection as well as the enhancement of both the total and diffuse transmissions at wavelengths of 300-1100 nm, indicating lower solar weighted reflectance (RSW) of ∼8.2%, higher solar weighted transmittance (TSW) of ∼93.1%, and considerably improved average haze ratio (HAvg) of ∼88.3% as compared to the bare PET (i.e., RSW ≈ 13.5%, TSW ≈ 86.9%, and HAvg ≈ 9.1%), respectively. Additionally, it shows a relatively good durability at temperatures of ≤160 °C. The resulting Si PV module with the NOA63 MGS/PET has an enhanced power conversion efficiency (PCE) of 13.26% (cf., PCE = 12.55% for the reference PV module with the bare PET) due to the mainly improved short circuit current from 49.35 to 52.01 mA, exhibiting the PCE increment percentage of ∼5.7%. For light incident angle-dependent PV module current-voltage characteristics, superior solar energy conversion properties are also obtained in a broad angle range of 10-80°.

A Fundamental Study on Spectrum Center Estimation of Solar Spectral Irradiation by the Statistical Pattern Recognition

NASA Astrophysics Data System (ADS)

Iijima, Aya; Suzuki, Kazumi; Wakao, Shinji; Kawasaki, Norihiro; Usami, Akira

With a background of environmental problems and energy issues, it is expected that PV systems will be introduced rapidly and connected with power grids on a large scale in the future. For this reason, the concern to which PV power generation will affect supply and demand adjustment in electric power in the future arises and the technique of correctly grasping the PV power generation becomes increasingly important. The PV power generation depends on solar irradiance, temperature of a module and solar spectral irradiance. Solar spectral irradiance is distribution of the strength of the light for every wavelength. As the spectrum sensitivity of solar cell depends on kind of solar cell, it becomes important for exact grasp of PV power generation. Especially the preparation of solar spectral irradiance is, however, not easy because the observational instrument of solar spectral irradiance is expensive. With this background, in this paper, we propose a new method based on statistical pattern recognition for estimating the spectrum center which is representative index of solar spectral irradiance. Some numerical examples obtained by the proposed method are also presented.

A definition study of the on-orbit assembly operations for the outboard photovoltaic power modules for Space Station Freedom. M.S. Thesis - Toledo Univ.

NASA Technical Reports Server (NTRS)

Sours, Thomas J.

1989-01-01

A concept is described for the assembly of the outboard PV modules for Space Station Freedom. Analysis of the on-orbit assembly operations was performed using CADAM design graphics software. A scenario for assembly using the various assembly equipment, as currently defined, is described in words, tables and illustrations. This work is part of ongoing studies in the area of space station assembly. The outboard PV module and the assembly equipment programs are all in definition and preliminary design phases. An input is provided to the design process of assembly equipment programs. It is established that the outboard PV module assembly operations can be performed using the assembly equipment currently planned in the Space Station Freedom Program.

Interactive smart battery storage for a PV and wind hybrid energy management control based on conservative power theory

NASA Astrophysics Data System (ADS)

Godoy Simões, Marcelo; Davi Curi Busarello, Tiago; Saad Bubshait, Abdullah; Harirchi, Farnaz; Antenor Pomilio, José; Blaabjerg, Frede

2016-04-01

This paper presents interactive smart battery-based storage (BBS) for wind generator (WG) and photovoltaic (PV) systems. The BBS is composed of an asymmetric cascaded H-bridge multilevel inverter (ACMI) with staircase modulation. The structure is parallel to the WG and PV systems, allowing the ACMI to have a reduction in power losses compared to the usual solution for storage connected at the DC-link of the converter for WG or PV systems. Moreover, the BBS is embedded with a decision algorithm running real-time energy costs, plus a battery state-of-charge manager and power quality capabilities, making the described system in this paper very interactive, smart and multifunctional. The paper describes how BBS interacts with the WG and PV and how its performance is improved. Experimental results are presented showing the efficacy of this BBS for renewable energy applications.

2015 Inverter Workshop | Photovoltaic Research | NREL

Science.gov Websites

Utility PV Inverters-Ron Vidano, Advanced Energy Module Level Power Electronics-Jack Flicker (Chair ), Sandia National Laboratories Standardization and Reliability Testing of Module-Level Power Electronics Failure Modes in Inverters-Diganta Das, CALCE Corrosion of Electronics-Rob Sorensen, Sandia National

Estimation of PV energy production based on satellite data

NASA Astrophysics Data System (ADS)

Mazurek, G.

2015-09-01

Photovoltaic (PV) technology is an attractive source of power for systems without connection to power grid. Because of seasonal variations of solar radiation, design of such a power system requires careful analysis in order to provide required reliability. In this paper we present results of three-year measurements of experimental PV system located in Poland and based on polycrystalline silicon module. Irradiation values calculated from results of ground measurements have been compared with data from solar radiation databases employ calculations from of satellite observations. Good convergence level of both data sources has been shown, especially during summer. When satellite data from the same time period is available, yearly and monthly production of PV energy can be calculated with 2% and 5% accuracy, respectively. However, monthly production during winter seems to be overestimated, especially in January. Results of this work may be helpful in forecasting performance of similar PV systems in Central Europe and allow to make more precise forecasts of PV system performance than based only on tables with long time averaged values.

Supported PV module assembly

DOEpatents

Mascolo, Gianluigi; Taggart, David F.; Botkin, Jonathan D.; Edgett, Christopher S.

2013-10-15

A supported PV assembly may include a PV module comprising a PV panel and PV module supports including module supports having a support surface supporting the module, a module registration member engaging the PV module to properly position the PV module on the module support, and a mounting element. In some embodiments the PV module registration members engage only the external surfaces of the PV modules at the corners. In some embodiments the assembly includes a wind deflector with ballast secured to a least one of the PV module supports and the wind deflector. An array of the assemblies can be secured to one another at their corners to prevent horizontal separation of the adjacent corners while permitting the PV modules to flex relative to one another so to permit the array of PV modules to follow a contour of the support surface.

Investigating the Effect of Titanium Dioxide (TiO2) Pollution on the Performance of the Mono-crystalline Solar Module

NASA Astrophysics Data System (ADS)

Ahmed Darwish, Zeki; Sopian, K.; Kazem, Hussein A.; Alghoul, M. A.; Alawadhi, Hussain

2017-11-01

This paper presents a study of titanium oxide TiO2 as one of the components of dust pollution affecting the PV performance. This pollutant can be found in various quantities in different locations around the world. The production of energy by different types of photovoltaic systems is very sensitive and depends on various environmental factors. Dust is one of the main contributing factors, yet the type of the dust is often neglected when studying the behaviour of the solar panel. In this experimental work we have studied the performance of the monocrystalline solar module as affected by the density of TiO2. The reduction of the PV module power caused by titanium dioxide under various mass densities was investigated. The results showed that the TiO2 has a significant effect on the PV output power. The dust density varied between 0-125 g.m-2. The corresponding reduction of the PV output power increased from 0 to 86.7%. This is based on various influencing parameters such as: short circuit current (Isc), maximum current (Im), open circuit voltage (Voc), maximum voltage (Vm), maximum power (Pm) and efficiency (E). Two functions are proposed as a mathematical model in order to explain this behaviour, namely the exponential and Fourier functions. The coefficients of all general models are valid for this type of dust with a density value ranging from 0-125 g.m-2.

PVMirrors: Hybrid PV/CSP collectors that enable lower LCOEs

NASA Astrophysics Data System (ADS)

Fisher, Kate; Yu, Zhengshan Jason; Striling, Rob; Holman, Zachary

2017-06-01

The primary challenge with concentrating solar power (CSP) is that the conversion efficiency is low—and the cost high—compared to that of photovoltaics (PV), and the primary challenge with PV is that the energy generated cannot be stored cost effectively. We introduce a technology that hybridizes CSP and PV, resulting in power plants with high energy conversion efficiency and affordable storage. This is accomplished by replacing silvered troughs (or heliostat facets) with "PVMirrors" that and direct photons of each wavelength to the converter (PV or thermal) that may best use them. A PVMirror looks like a curved PV module that includes a spectrum-splitting dichroic mirror film; this film, which is the heart of the technology, transmits near-infrared light to the underlying silicon PV cells while reflecting both longer and shorter wavelengths to a thermal absorber tube. This paper investigates the optical performance of dichroic mirror film, the specularity of PVMirrors, and the anticipated levelized cost of energy (LCOE) from a PVMirror power plant. PVMirrors are found to decrease LCOE by more than 15% relative to CSP while retaining full dispatchability.

Intermediate Photovoltaic System Application Experiment. Oklahoma Center for Science and Arts. Phase II. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

This report presents the key results of the Phase II efforts for the Intermediate PV System Applications Experiment at the Oklahoma Center for Science and Arts (OCSA). This phase of the project involved fabrication, installation and integration of a nominal 140 kW flat panel PV system made up of large, square polycrystalline-silicon solar cell modules, each nominally 61 cm x 122 cm in size. The output of the PV modules, supplied by Solarex Corporation, was augmented, 1.35 to 1 at peak, by a row of glass reflectors, appropriately tilted northward. The PV system interfaces with the Oklahoma Gas and Electricmore » Utility at the OCSA main switchgear. Any excess power generated by the system is fed into the utility under a one to one buyback arrangement. Except for a shortfall in the system output, presently suspected to be due to the poor performance of the modules, no serious problems were encountered. Certain value engineering changes implemented during construction and early operational failure events associated with the power conditioning system are also described. The system is currently undergoing extended testing and evaluation.« less

Impact of distributed power electronics on the lifetime and reliability of PV systems: Impact of distributed power electronics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Olalla, Carlos; Maksimovic, Dragan; Deline, Chris

Here, this paper quantifies the impact of distributed power electronics in photovoltaic (PV) systems in terms of end-of-life energy-capture performance and reliability. The analysis is based on simulations of PV installations over system lifetime at various degradation rates. It is shown how module-level or submodule-level power converters can mitigate variations in cell degradation over time, effectively increasing the system lifespan by 5-10 years compared with the nominal 25-year lifetime. An important aspect typically overlooked when characterizing such improvements is the reliability of distributed power electronics, as power converter failures may not only diminish energy yield improvements but also adversely affectmore » the overall system operation. Failure models are developed, and power electronics reliability is taken into account in this work, in order to provide a more comprehensive view of the opportunities and limitations offered by distributed power electronics in PV systems. Lastly, it is shown how a differential power-processing approach achieves the best mismatch mitigation performance and the least susceptibility to converter faults.« less

Impact of distributed power electronics on the lifetime and reliability of PV systems: Impact of distributed power electronics

DOE PAGES

Olalla, Carlos; Maksimovic, Dragan; Deline, Chris; ...

2017-04-26

Here, this paper quantifies the impact of distributed power electronics in photovoltaic (PV) systems in terms of end-of-life energy-capture performance and reliability. The analysis is based on simulations of PV installations over system lifetime at various degradation rates. It is shown how module-level or submodule-level power converters can mitigate variations in cell degradation over time, effectively increasing the system lifespan by 5-10 years compared with the nominal 25-year lifetime. An important aspect typically overlooked when characterizing such improvements is the reliability of distributed power electronics, as power converter failures may not only diminish energy yield improvements but also adversely affectmore » the overall system operation. Failure models are developed, and power electronics reliability is taken into account in this work, in order to provide a more comprehensive view of the opportunities and limitations offered by distributed power electronics in PV systems. Lastly, it is shown how a differential power-processing approach achieves the best mismatch mitigation performance and the least susceptibility to converter faults.« less

Development and design of photovoltaic power prediction system

NASA Astrophysics Data System (ADS)

Wang, Zhijia; Zhou, Hai; Cheng, Xu

2018-02-01

In order to reduce the impact of power grid safety caused by volatility and randomness of the energy produced in photovoltaic power plants, this paper puts forward a construction scheme on photovoltaic power generation prediction system, introducing the technical requirements, system configuration and function of each module, and discussing the main technical features of the platform software development. The scheme has been applied in many PV power plants in the northwest of China. It shows that the system can produce reasonable prediction results, providing a right guidance for dispatching and efficient running for PV power plant.

Optimal Configuration of PV System with Different Solar Cell Arrays

NASA Astrophysics Data System (ADS)

Machida, Sadayuki; Tani, Tatsuo

Photovoltaic (PV) power generation is spreading steadily, and the dispersed PV array system is increasing from the architectural restrictions. In the case of dispersed array system, if the arrays are installed in a different azimuth or if the module that constitutes array is different, mismatching loss will be generated when a single inverter is used to convert the output of arrays, because of the difference of optimal operating voltage. The loss is related to the array configuration. However the relation between array configuration and power generation output is not clear. In order to avoid generation of mismatching loss, introducing a distributed inverter system such as string inverter system or AC modules system is considered. However it is not clear which is more advantageous between a distributed system and a concentrated system. In this paper, we verified the output characteristics of two different solar cell arrays with various strings, azimuths and tilt angles, and clarified the relation between array configuration and power generation output by the computer simulations. We also compared the distributed inverter system with the concentrated inverter system, and clarified the optimal configuration of PV system with different solar cell arrays.

Photovoltaic System Modeling. Uncertainty and Sensitivity Analyses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hansen, Clifford W.; Martin, Curtis E.

2015-08-01

We report an uncertainty and sensitivity analysis for modeling AC energy from ph otovoltaic systems . Output from a PV system is predicted by a sequence of models. We quantify u ncertainty i n the output of each model using empirical distribution s of each model's residuals. We propagate uncertainty through the sequence of models by sampli ng these distributions to obtain a n empirical distribution of a PV system's output. We consider models that: (1) translate measured global horizontal, direct and global diffuse irradiance to plane - of - array irradiance; (2) estimate effective irradiance; (3) predict cell temperature;more » (4) estimate DC voltage, current and power ; (5) reduce DC power for losses due to inefficient maximum power point tracking or mismatch among modules; and (6) convert DC to AC power . O ur analysis consider s a notional PV system com prising an array of FirstSolar FS - 387 modules and a 250 kW AC inverter ; we use measured irradiance and weather at Albuquerque, NM. We found the uncertainty in PV syste m output to be relatively small, on the order of 1% for daily energy. We found that unce rtainty in the models for POA irradiance and effective irradiance to be the dominant contributors to uncertainty in predicted daily energy. Our analysis indicates that efforts to reduce the uncertainty in PV system output predictions may yield the greatest improvements by focusing on the POA and effective irradiance models.« less

Development of a Solar Cell Back Sheet with Excellent UV Durability and Thermal Conductivity.

PubMed

Kang, Seong-Hwan; Choi, Jaeho; Lee, Sung-Ho; Song, Young-Hoon; Park, Jong-Se; Jung, In-Sung; Jung, Jin-Su; Kim, Chong-Yeal; Yang, O-Bong

2018-09-01

The back sheet is one of the most important materials in photovoltaic (PV) modules. It plays an important role in protecting the solar cell from the environment by preventing moisture penetration. In the back sheet, the outermost layer is composed of a polyester (PET) film to protect the PV module from moisture, and the opposite layer is composed of a TiO2 + PE material. Nowadays, PV modules are installed in the desert. Therefore, methods to improve the power generation efficiency of PV modules need to be investigated as the efficiency is affected by temperature resulting from the heat radiation effect. Using a back sheet with a high thermal conductivity, the module output efficiency can be increased as heat is efficiently dissipated. In this study, a thermally conductive film was fabricated by mixing a reference film (TiO2 + PE) and a non-metallic material, MgO, with high thermal conductivity. UV irradiation tests of the film were conducted. The thermally conductive film (TiO2 + PE + MgO) showed higher conductivity than a reference film. No visible cracks and low yellowing degree were found in thermally conductive film, confirming its excellent UV durability characteristics. The sample film was bonded to a PET layer, and a back sheet was fabricated. The yellowing of the back sheet was also analyzed after UV irradiation. In addition, mini modules with four solar cell were fabricated using the developed back sheet, and a comparative outdoor test was conducted. The results showed that power generation improved by 1.38%.

The influence of utility-interactive PV system characteristics to ac power networks

NASA Astrophysics Data System (ADS)

Takeda, Y.; Takigawa, K.; Kaminosono, H.

Two basic experimental photovoltaic (PV) systems have been built for the study of variation of power quality, aspects of safety, and technical problems. One system uses a line-commutated inverter, while the other system uses a self-commutated inverter. A description is presented of the operating and generating characteristics of the two systems. The systems were connected to an ac simulated network which simulates an actual power distribution system. Attention is given to power generation characteristics, the control characteristics, the harmonics characteristics, aspects of coordination with the power network, and questions regarding the reliability of photovoltaic modules.

Quantitative Analysis Method of Output Loss due to Restriction for Grid-connected PV Systems

NASA Astrophysics Data System (ADS)

Ueda, Yuzuru; Oozeki, Takashi; Kurokawa, Kosuke; Itou, Takamitsu; Kitamura, Kiyoyuki; Miyamoto, Yusuke; Yokota, Masaharu; Sugihara, Hiroyuki

Voltage of power distribution line will be increased due to reverse power flow from grid-connected PV systems. In the case of high density grid connection, amount of voltage increasing will be higher than the stand-alone grid connection system. To prevent the over voltage of power distribution line, PV system's output will be restricted if the voltage of power distribution line is close to the upper limit of the control range. Because of this interaction, amount of output loss will be larger in high density case. This research developed a quantitative analysis method for PV systems output and losses to clarify the behavior of grid connected PV systems. All the measured data are classified into the loss factors using 1 minute average of 1 second data instead of typical 1 hour average. Operation point on the I-V curve is estimated to quantify the loss due to the output restriction using module temperature, array output voltage, array output current and solar irradiance. As a result, loss due to output restriction is successfully quantified and behavior of output restriction is clarified.

All About PID - Testing and Avoidance in the Field

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hacke, Peter; Johnston, Steve

2016-09-01

Potential-induced degradation can cause significant power loss in modules if the appropriate precautions are not taken. In the first part of a new series in PV Tech Power on module failure, Peter Hacke and Steve Johnston assess the current state-of-the-art in detecting, avoiding and mitigating the worst effects of PID.

Behavioral data of thin-film single junction amorphous silicon (a-Si) photovoltaic modules under outdoor long term exposure

PubMed Central

Kichou, Sofiane; Silvestre, Santiago; Nofuentes, Gustavo; Torres-Ramírez, Miguel; Chouder, Aissa; Guasch, Daniel

2016-01-01

Four years׳ behavioral data of thin-film single junction amorphous silicon (a-Si) photovoltaic (PV) modules installed in a relatively dry and sunny inland site with a Continental-Mediterranean climate (in the city of Jaén, Spain) are presented in this article. The shared data contributes to clarify how the Light Induced Degradation (LID) impacts the output power generated by the PV array, especially in the first days of exposure under outdoor conditions. Furthermore, a valuable methodology is provided in this data article permitting the assessment of the degradation rate and the stabilization period of the PV modules. Further discussions and interpretations concerning the data shared in this article can be found in the research paper “Characterization of degradation and evaluation of model parameters of amorphous silicon photovoltaic modules under outdoor long term exposure” (Kichou et al., 2016) [1]. PMID:26977439

Photovoltaic roofing tile systems

NASA Astrophysics Data System (ADS)

Melchior, B.

The integration of photovoltaic (PV) systems in architecture is discussed. A PV-solar roofing tile system with polymer concrete base; PV-roofing tile with elastomer frame profiles and aluminum profile frames; contact technique; and solar cell modules measuring technique are described. Field tests at several places were conducted on the solar generator, electric current behavior, battery station, electric installation, power conditioner, solar measuring system with magnetic bubble memory technique, data transmission via telephone modems, and data processing system. The very favorable response to the PV-compact system proves the commercial possibilities of photovoltaic integration in architecture.

Some tests of flat plate photovoltaic module cell temperatures in simulated field conditions

NASA Technical Reports Server (NTRS)

Griffith, J. S.; Rathod, M. S.; Paslaski, J.

1981-01-01

The nominal operating cell temperature (NOCT) of solar photovoltaic (PV) modules is an important characteristic. Typically, the power output of a PV module decreases 0.5% per deg C rise in cell temperature. Several tests were run with artificial sun and wind to study the parametric dependencies of cell temperature on wind speed and direction and ambient temperature. It was found that the cell temperature is extremely sensitive to wind speed, moderately so to wind direction and rather insensitive to ambient temperature. Several suggestions are made to obtain data more typical of field conditions.

Analysis of twelve-month degradation in three polycrystalline photovoltaic modules

NASA Astrophysics Data System (ADS)

Lai, T.; Potter, B. G.; Simmons-Potter, K.

2016-09-01

Polycrystalline silicon photovoltaic (PV) modules have the advantage of lower manufacturing cost as compared to their monocrystalline counterparts, but generally exhibit both lower initial module efficiencies and more significant early-stage efficiency degradation than do similar monocrystalline PV modules. For both technologies, noticeable deterioration in power conversion efficiency typically occurs over the first two years of usage. Estimating PV lifetime by examining the performance degradation behavior under given environmental conditions is, therefore, one of continual goals for experimental research and economic analysis. In the present work, accelerated lifecycle testing (ALT) on three polycrystalline PV technologies was performed in a full-scale, industrial-standard environmental chamber equipped with single-sun irradiance capability, providing an illumination uniformity of 98% over a 2 x 1.6m area. In order to investigate environmental aging effects, timedependent PV performance (I-V characteristic) was evaluated over a recurring, compressed day-night cycle, which simulated local daily solar insolation for the southwestern United States, followed by dark (night) periods. During a total test time of just under 4 months that corresponded to a year equivalent exposure on a fielded module, the temperature and humidity varied in ranges from 3°C to 40°C and 5% to 85% based on annual weather profiles for Tucson, AZ. Removing the temperature de-rating effect that was clearly seen in the data enabled the computation of normalized efficiency degradation with time and environmental exposure. Results confirm the impact of environmental conditions on the module long-term performance. Overall, more than 2% efficiency degradation in the first year of usage was observed for all thee polycrystalline Si solar modules. The average 5-year degradation of each PV technology was estimated based on their determined degradation rates.

PV module mounting method and mounting assembly

DOEpatents

Lenox, Carl J.S.; Johnson, Kurt M.

2013-04-23

A method for mounting PV modules to a deck includes selecting PV module layout pattern so that adjacent PV module edges are spaced apart. PV mounting and support assemblies are secured to the deck according to the layout pattern using fasteners extending into the deck. The PV modules are placed on the PV mounting and support assemblies. Retaining elements are located over and secured against the upper peripheral edge surfaces of the PV modules so to secure them to the deck with the peripheral edges of the PV modules spaced apart from the deck. In some examples a PV module mounting assembly, for use on a shingled deck, comprises flashing, a base mountable on the flashing, a deck-penetrating fastener engageable with the base and securable to the deck so to secure the flashing and the base to the shingled deck, and PV module mounting hardware securable to the base.

Failure and Degradation Modes of PV modules in a Hot Dry Climate: Results after 4 and 12 years of field exposure

NASA Astrophysics Data System (ADS)

Mallineni, Jaya krishna

This study evaluates two photovoltaic (PV) power plants based on electrical performance measurements, diode checks, visual inspections and infrared scanning. The purpose of this study is to measure degradation rates of performance parameters (Pmax, Isc, Voc, Vmax, Imax and FF) and to identify the failure modes in a "hot-dry desert" climatic condition along with quantitative determination of safety failure rates and reliability failure rates. The data obtained from this study can be used by module manufacturers in determining the warranty limits of their modules and also by banks, investors, project developers and users in determining appropriate financing or decommissioning models. In addition, the data obtained in this study will be helpful in selecting appropriate accelerated stress tests which would replicate the field failures for the new modules and would predict the lifetime for new PV modules. The study was conducted at two, single axis tracking monocrystalline silicon (c-Si) power plants, Site 3 and Site 4c of Salt River Project (SRP). The Site 3 power plant is located in Glendale, Arizona and the Site 4c power plant is located in Mesa, Arizona both considered a "hot-dry" field condition. The Site 3 power plant has 2,352 modules (named as Model-G) which was rated at 250 kW DC output. The mean and median degradation of these 12 years old modules are 0.95%/year and 0.96%/year, respectively. The major cause of degradation found in Site 3 is due to high series resistance (potentially due to solder-bond thermo-mechanical fatigue) and the failure mode is ribbon-ribbon solder bond failure/breakage. The Site 4c power plant has 1,280 modules (named as Model-H) which provide 243 kW DC output. The mean and median degradation of these 4 years old modules are 0.96%/year and 1%/year, respectively. At Site 4c, practically, none of the module failures are observed. The average soiling loss is 6.9% in Site 3 and 5.5% in Site 4c. The difference in soiling level is attributed to the rural and urban surroundings of these two power plants.

Apparatus and method for mounting photovoltaic power generating systems on buildings

DOEpatents

Russell, Miles Clayton [Lincoln, MA

2008-10-14

Rectangular PV modules (6) are mounted on a building roof (4) by mounting stands that are distributed in rows and columns. Each stand comprises a base plate (10) that rests on the building roof (4) and first and second brackets (12, 14) of different height attached to opposite ends of the base plate (10). Each bracket (12, 14) has dual members for supporting two different PV modules (6), and each PV module (6) has a mounting pin (84) adjacent to each of its four corners. Each module (6) is supported by attachment of two of its mounting pins (84) to different first brackets (12), whereby the modules (6) and their supporting stands are able to resist uplift forces resulting from high velocity winds without the base plates (10) being physically attached to the supporting roof structure (4). Preferably the second brackets (14) have a telescoping construction that permits their effective height to vary from less than to substantially the same as that of the first brackets (12).

Ballasted photovoltaic module and module arrays

DOEpatents

Botkin, Jonathan [El Cerrito, CA; Graves, Simon [Berkeley, CA; Danning, Matt [Oakland, CA

2011-11-29

A photovoltaic (PV) module assembly including a PV module and a ballast tray. The PV module includes a PV device and a frame. A PV laminate is assembled to the frame, and the frame includes an arm. The ballast tray is adapted for containing ballast and is removably associated with the PV module in a ballasting state where the tray is vertically under the PV laminate and vertically over the arm to impede overt displacement of the PV module. The PV module assembly can be installed to a flat commercial rooftop, with the PV module and the ballast tray both resting upon the rooftop. In some embodiments, the ballasting state includes corresponding surfaces of the arm and the tray being spaced from one another under normal (low or no wind) conditions, such that the frame is not continuously subjected to a weight of the tray.

Impact of heavy soiling on the power output of PV modules

NASA Astrophysics Data System (ADS)

Schill, Christian; Brachmann, Stefan; Heck, Markus; Weiss, Karl-Anders; Koehl, Michael

2011-09-01

Fraunhofer ISE is running a PV-module outdoor testing set-up on the Gran Canaria island, one of the Canary Island located west of Morroco in the Atlantic Ocean. The performance of the modules is assessed by IV-curve monitoring every 10 minutes. The electronic set-up of the monitoring system - consisting of individual electronic loads for each module which go into an MPP-tracking mode between the IV-measurements - will be described in detail. Soiling of the exposed modules happened because of building constructions nearby. We decided not to clean the modules, but the radiation sensors and recorded the decrease of the power output and the efficiency over time. The efficiency dropped to 20 % within 5 months before a heavy rain and subsequently the service personnel on site cleaned the modules. A smaller rain-fall in between washed the dust partly away and accumulated it at the lower part of the module, what could be concluded from the shape of the IV-curves, which were similar to partial shading by hot-spot-tests and by partial snow cover.

Holographic lens spectrum splitting photovoltaic system for increased diffuse collection and annual energy yield

NASA Astrophysics Data System (ADS)

Vorndran, Shelby D.; Wu, Yuechen; Ayala, Silvana; Kostuk, Raymond K.

2015-09-01

Concentrating and spectrum splitting photovoltaic (PV) modules have a limited acceptance angle and thus suffer from optical loss under off-axis illumination. This loss manifests itself as a substantial reduction in energy yield in locations where a significant portion of insulation is diffuse. In this work, a spectrum splitting PV system is designed to efficiently collect and convert light in a range of illumination conditions. The system uses a holographic lens to concentrate shortwavelength light onto a smaller, more expensive indium gallium phosphide (InGaP) PV cell. The high efficiency PV cell near the axis is surrounded with silicon (Si), a less expensive material that collects a broader portion of the solar spectrum. Under direct illumination, the device achieves increased conversion efficiency from spectrum splitting. Under diffuse illumination, the device collects light with efficiency comparable to a flat-panel Si module. Design of the holographic lens is discussed. Optical efficiency and power output of the module under a range of illumination conditions from direct to diffuse are simulated with non-sequential raytracing software. Using direct and diffuse Typical Metrological Year (TMY3) irradiance measurements, annual energy yield of the module is calculated for several installation sites. Energy yield of the spectrum splitting module is compared to that of a full flat-panel Si reference module.

PV system field experience and reliability

NASA Astrophysics Data System (ADS)

Durand, Steven; Rosenthal, Andrew; Thomas, Mike

1997-02-01

Hybrid power systems consisting of battery inverters coupled with diesel, propane, or gasoline engine-driven electrical generators, and photovoltaic arrays are being used in many remote locations. The potential cost advantages of hybrid systems over simple engine-driven generator systems are causing hybrid systems to be considered for numerous applications including single-family residential, communications, and village power. This paper discusses the various design constraints of such systems and presents one technique for reducing hybrid system losses. The Southwest Technology Development Institute under contract to the National Renewable Energy Laboratory and Sandia National Laboratories has been installing data acquisition systems (DAS) on a number of small and large hybrid PV systems. These systems range from small residential systems (1 kW PV - 7 kW generator), to medium sized systems (10 kW PV - 20 kW generator), to larger systems (100 kW PV - 200 kW generator). Even larger systems are being installed with hundreds of kilowatts of PV modules, multiple wind machines, and larger diesel generators.

Detection and location of fouling on photovoltaic panels using a drone-mounted infrared thermography system

NASA Astrophysics Data System (ADS)

Zhang, Peng; Zhang, Lifu; Wu, Taixia; Zhang, Hongming; Sun, Xuejian

2017-01-01

Due to weathering and external forces, solar panels are subject to fouling and defects after a certain amount of time in service. These fouling and defects have direct adverse consequences such as low-power efficiency. Because solar power plants usually have large-scale photovoltaic (PV) panels, fast detection and location of fouling and defects across large PV areas are imperative. A drone-mounted infrared thermography system was designed and developed, and its ability to detect rapid fouling on large-scale PV panel systems was investigated. The infrared images were preprocessed using the K neighbor mean filter, and the single PV module on each image was recognized and extracted. Combining the local and global detection method, suspicious sites were located precisely. The results showed the flexible drone-mounted infrared thermography system to have a strong ability to detect the presence and determine the position of PV fouling. Drone-mounted infrared thermography also has good technical feasibility and practical value in the detection of PV fouling detection.

Power conversion and control methods for renewable energy sources

NASA Astrophysics Data System (ADS)

Yu, Dachuan

2005-07-01

In recent years, there has been an increase in the use of renewable energy due to the growing concern over the pollution caused by fossil-fuel-based energy. Renewable energy sources, such as photovoltaic (PV) and fuel cell, can be used to enhance the safety, reliability, sustainability, and transmission efficiency of a power system. This dissertation focuses on the power conversion and control for two major renewable-energy sources: PV and fuel cell. Firstly, a current-based, maximum power-point tracking (MPPT) algorithm is proposed for PV energy. An economical converter system using the above scheme for converting the output from PV panels into 60 Hz AC voltage is developed and built. Secondly, a novel circuit model for the Proton Exchange Membrane (PEM) fuel-cell stack that is useful in the design and analysis of fuel-cell-based power systems is proposed. This Pspice-based model uses elements available in the Pspice library with some modifications to represent both the static and dynamic responses of a PEM fuel-cell module. The accuracy of the model is verified by comparing the simulation and experimental results. Thirdly, a DSP-controlled three-phase induction-motor drive using constant voltage over frequency is built and can be used in a fuel-cell automobile. A hydrogen sensor is used in the drive to both sound an alarm and shut down the inverter trigger pulses through the DSP. Finally, a hybrid power system consisting of PV panels and fuel cell is proposed and built. In the proposed system, PV panels can supply most of the power when the sunlight is available, and the excess power required by the load is supplied by a fuel cell. Load sharing between a fuel cell (FC) and the PV panel is investigated by both simulation and experiments.

A control strategy for PV stand-alone applications

NASA Astrophysics Data System (ADS)

Slouma, S.; Baccar, H.

2015-04-01

This paper proposes a stand-alone photovoltaic (PV) system study in domestic applications. Because of the decrease in power of photovoltaic module as a consequence of changes in solar radiation and temperature which affect the photovoltaic module performance, the design and control of DC-DC buck converter was proposed for providing power to the load from a photovoltaic source.In fact, the control of this converter is carried out with integrated MPPT (Maximum Power Point Tracking) algorithm which ensures a maximum energy generated by the PV arrays. Moreover, the output stage is composed by a battery energy storage system, dc-ac inverter, LCL filter which enables higher efficiency, low distortion ac waveforms and low leakage currents. The control strategy adopted is cascade control composed by two regulation loops.Simulations performed with PSIM software were able to validate the control system.The realization and testing of the photovoltaic system were achieved in the Photovoltaic laboratory of the Centre for Research and Energy Technologies at the Technopark Borj Cedria. Experimental results verify the effeciency of the proposed system.

Practical Efficiency of Photovoltaic Panel Used for Solar Vehicles

NASA Astrophysics Data System (ADS)

Koyuncu, T.

2017-08-01

In this experimental investigation, practical efficiency of semi-flexible monocrystalline silicon solar panel used for a solar powered car called “Firat Force” and a solar powered minibus called “Commagene” was determined. Firat Force has 6 solar PV modules, a maintenance free long life gel battery pack, a regenerative brushless DC electric motor and Commagene has 12 solar PV modules, a maintenance free long life gel battery pack, a regenerative brushless DC electric motor. In addition, both solar vehicles have MPPT (Maximum power point tracker), ECU (Electronic control unit), differential, instrument panel, steering system, brake system, brake and gas pedals, mechanical equipments, chassis and frame. These two solar vehicles were used for people transportation in Adiyaman city, Turkey, during one year (June 2010-May 2011) of test. As a result, the practical efficiency of semi-flexible monocrystalline silicon solar panel used for Firat Force and Commagene was determined as 13 % in despite of efficiency value of 18% (at 1000 W/m2 and 25 °C ) given by the producer company. Besides, the total efficiency (from PV panels to vehicle wheel) of the system was also defined as 9%.

Applying photovoltaics to disaster relief

DOE Office of Scientific and Technical Information (OSTI.GOV)

Young, W. Jr.

1996-11-01

Hurricanes, floods, tornados, earthquakes and other disasters can happen at any time, often with little or no advance warning. They can be as destructive as Hurricane Andrew leaving several hundred-thousand people homeless or as minor as an afternoon thunderstorm knocking down local power lines to your home. Major disasters leave many people without adequate medical services, potable water, electrical service and communications. In response to a natural disaster, photovoltaic (solar electric) modules offer a source of quiet, safe, pollution-free electrical power. Photovoltaic (PV) power systems are capable of providing the electrical needs for vaccine refrigerators, microscopes, medical equipment, lighting, radios,more » fans, communications, traffic devices and other general electrical needs. Stand alone PV systems do not require refueling and operate for long period of time from the endless energy supplied by the sun, making them beneficial during recovery efforts. This report discusses the need for electrical power during a disaster, and the capability of PV to fill that need. Applications of PV power used during previous disaster relief efforts are also presented.« less

On the Path to SunShot. The Role of Advancements in Solar Photovoltaic Efficiency, Reliability, and Costs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Woodhouse, Michael; Jones-Albertus, Rebecca; Feldman, David

2016-05-01

This report examines the remaining challenges to achieving the competitive photovoltaic (PV) costs and large-scale deployment envisioned under the U.S. Department of Energy's SunShot Initiative. Solar-energy cost reductions can be realized through lower PV module and balance-of-system (BOS) costs as well as improved system efficiency and reliability. Numerous combinations of PV improvements could help achieve the levelized cost of electricity (LCOE) goals because of the tradeoffs among key metrics like module price, efficiency, and degradation rate as well as system price and lifetime. Using LCOE modeling based on bottom-up cost analysis, two specific pathways are mapped to exemplify the manymore » possible approaches to module cost reductions of 29%-38% between 2015 and 2020. BOS hardware and soft cost reductions, ranging from 54%-77% of total cost reductions, are also modeled. The residential sector's high supply-chain costs, labor requirements, and customer-acquisition costs give it the greatest BOS cost-reduction opportunities, followed by the commercial sector, although opportunities are available to the utility-scale sector as well. Finally, a future scenario is considered in which very high PV penetration requires additional costs to facilitate grid integration and increased power-system flexibility--which might necessitate even lower solar LCOEs. The analysis of a pathway to 3-5 cents/kWh PV systems underscores the importance of combining robust improvements in PV module and BOS costs as well as PV system efficiency and reliability if such aggressive long-term targets are to be achieved.« less

Simulated potential for enhanced performance of mechanically stacked hybrid III–V/Si tandem photovoltaic modules using DC–DC converters

DOE PAGES

MacAlpine, Sara; Bobela, David C.; Kurtz, Sarah; ...

2017-10-01

This work examines a tandem module design with GaInP2 mechanically stacked on top of crystalline Si, using a detailed photovoltaic (PV) system model to simulate four-terminal (4T) unconstrained and two-terminal voltage-matched (2T VM) parallel architectures. Module-level power electronics is proposed for the 2T VM module design to enhance its performance over the breadth of temperatures experienced by a typical PV installation. Annual, hourly simulations of various scenarios indicate that this design can reduce annual energy losses to ~0.5% relative to the 4T module configuration. Consideration is given to both performance and practical design for building or ground mount installations, emphasizingmore » compatibility with existing standard Si modules.« less

Simulated potential for enhanced performance of mechanically stacked hybrid III–V/Si tandem photovoltaic modules using DC–DC converters

DOE Office of Scientific and Technical Information (OSTI.GOV)

MacAlpine, Sara; Bobela, David C.; Kurtz, Sarah

This work examines a tandem module design with GaInP2 mechanically stacked on top of crystalline Si, using a detailed photovoltaic (PV) system model to simulate four-terminal (4T) unconstrained and two-terminal voltage-matched (2T VM) parallel architectures. Module-level power electronics is proposed for the 2T VM module design to enhance its performance over the breadth of temperatures experienced by a typical PV installation. Annual, hourly simulations of various scenarios indicate that this design can reduce annual energy losses to ~0.5% relative to the 4T module configuration. Consideration is given to both performance and practical design for building or ground mount installations, emphasizingmore » compatibility with existing standard Si modules.« less

Simulated potential for enhanced performance of mechanically stacked hybrid III-V/Si tandem photovoltaic modules using DC-DC converters

NASA Astrophysics Data System (ADS)

MacAlpine, Sara; Bobela, David C.; Kurtz, Sarah; Lumb, Matthew P.; Schmieder, Kenneth J.; Moore, James E.; Walters, Robert J.; Alberi, Kirstin

2017-10-01

This work examines a tandem module design with GaInP2 mechanically stacked on top of crystalline Si, using a detailed photovoltaic (PV) system model to simulate four-terminal (4T) unconstrained and two-terminal voltage-matched (2T VM) parallel architectures. Module-level power electronics is proposed for the 2T VM module design to enhance its performance over the breadth of temperatures experienced by a typical PV installation. Annual, hourly simulations of various scenarios indicate that this design can reduce annual energy losses to ˜0.5% relative to the 4T module configuration. Consideration is given to both performance and practical design for building or ground mount installations, emphasizing compatibility with existing standard Si modules.

Solar concentrator modules with silicone-onglass Fresnel lens panels and multijunction cells.

PubMed

Rumyantsev, Valery D

2010-04-26

High-efficiency multijunction (MJ) solar cells, being very expensive to manufacture, should only be used in combination with solar concentrators in terrestrial applications. An essential cost reduction of electric power produced by photovoltaic (PV) installations with MJ cells, may be expected by the creation of highly-effective, but inexpensive, elements for optical concentration and sun tracking. This article is an overview of the corresponding approach under development at the Ioffe Physical Technical Institute. The approach to R&D of the solar PV modules is based on the concepts of sunlight concentration by small-aperture area Fresnel lenses and "all-glass" module design. The small-aperture area lenses are arranged as a panel with silicone-on-glass structure where the glass plate serves as the front surface of a module. In turn, high-efficiency InGaP/(In)GaAs/Ge cells are arranged on a rear module panel mounted on a glass plate which functions as a heat sink and integrated protective cover for the cells. The developed PV modules and sun trackers are characterized by simple design, and are regarded as the prototypes for further commercialization.

Evaluation of the PV energy production after 12-years of operating

NASA Astrophysics Data System (ADS)

Bouchakour, Salim; Arab, Amar Hadj; Abdeladim, Kamel; Boulahchiche, Saliha; Amrouche, Said Ould; Razagui, Abdelhak

2018-05-01

This paper presents a simple way to approximately evaluate the photovoltaic (PV) array performance degradation, the studied PV arrays are connected to the local electric grid at the Centre de Developpement des Energies Renouvelables (CDER) in Algiers, Algeria, since June 2004. The used PV module model takes in consideration the module temperature and the effective solar radiance, the electrical characteristics provided by the manufacturer data sheet and the evaluation of the performance coefficient. For the dynamic behavior we use the Linear Reoriented Coordinates Method (LRCM) to estimate the maximum power point (MPP). The performance coefficient is evaluated on the one hand under STC conditions to estimate the dc energy according to the manufacturer data. On the other hand, under real conditions using both the monitored data and the LM optimization algorithm, allowing a good degree of accuracy of estimated dc energy. The application of the developed modeling procedure to the analysis of the monitored data is expected to improve understanding and assessment of the PV performance degradation of the PV arrays after 12 years of operation.

Performance of a Low-Cost, Low-Concentration Photovoltaic Module

NASA Astrophysics Data System (ADS)

Shell, Kara A.; Brown, Scott A.; Schuetz, Mark A.; Davis, Bob J.; French, Roger H.

2011-12-01

In order to significantly reduce the cost of solar power, Replex Plastics has developed a low-cost, low-concentration PV module incorporating acrylic mirror reflectors. The reflectors are compound parabolic concentrators designed for use with low-accuracy single axis trackers. The prototypes use crystalline silicon photovoltaic cells and achieved 7.1x concentration over a receiver without reflectors. The 1×1.6 m module used 1/10th the silicon of a standard module and produced a max power of 140 W.

Why silicon is and will remain the dominant photovoltaic material

NASA Astrophysics Data System (ADS)

Singh, Rajendra

2009-07-01

Rising demands of energy in emerging economies, coupled with the green house gas emissions related problems around the globe have provided a unique opportunity of exploiting the advantages offered by photovoltaic (PV) systems for green energy electricity generation. Similar to cell phones, power generated by PV systems can reach over two billion people worldwide who have no access to clean energy. Only silicon based PV devices meet the low-cost manufacturing criterion of clean energy conversion (abundance of raw material and no environmental health and safety issues). The use of larger size glass substrates and manufacturing techniques similar to the ones used by the liquid crystal display industry and the large scale manufacturing of amorphous silicon thin films based modules (~ GW per year manufacturing at a single location) can lead to installed PV system cost of $3/Wp. This will open a huge market for grid connected PV systems and related markets. With further research and development, this approach can provide $2/Wp installed PV system costs in the next few years. At this cost level, PV electricity generation is competitive with any other technology, and PV power generation can be a dominant electricity generation technology in the 21st century.

Optimization and development of solar power system under diffused sunlight condition in rural areas with supercapacitor integration

NASA Astrophysics Data System (ADS)

Castelino, Roystan V.; Jana, Suman; Kumhar, Rajesh; Singh, Niraj K.

2018-04-01

The simulation and hardware based experiment in this presented paper shows a possibility of increasing the reliability of solar power under diffused condition by using super capacitor module. This experimental setup can be used in those areas where the sun light is intermittent and under the diffused radiation condition. Due to diffused radiation, solar PV cells operate very poorly, but by using this setup the power efficiency can be increased greatly. Sometimes dependent numerical models are used to measure the voltage and current response of the hardware setup in MATLAB Simulink based environment. To convert the scattered solar radiation to electricity using the conventional solar PV module, batteries have to be linked with the rapid charging or discharging device like super capacitor module. The conventional method consists of a charging circuit, which dumps the power if the voltage is below certain voltage level, but this circuit utilizes the entire power even if the voltage is low under diffused sun light conditions. There is no power dumped in this circuit. The efficiency and viability of this labscale experimental setup can be examined with further experiment and industrial model.

Photovoltaic power - An important new energy option

NASA Technical Reports Server (NTRS)

Ferber, R. R.

1983-01-01

A review of photovoltaic (PV) power technology is presented with an emphasis of PV as an economical and technically feasible alternative source of energy. The successful completion of the development and transfer of emerging low-cost technologies into a fully commercialized status are identified as the means to the realization of this option's full potential. The DOE National Photovoltaics Program, a significant sponsor of PV R&D, expects both flat-plate and concentrator collectors to meet established cost targets. Citing the DOE large flat-plate grid-connected system project of the Sacramento Municipal Utility District, current technology modules priced at near $5/Wp (1983 dollars) are steadily reducing costs. A recent DOE study suggests that PV-generated electricity produced at a 30-year levelized cost of 15 cents per kWh would represent a viable energy supply alternative for the nation.

Photovoltaic power - An important new energy option

NASA Astrophysics Data System (ADS)

Ferber, R. R.

1983-12-01

A review of photovoltaic (PV) power technology is presented with an emphasis of PV as an economical and technically feasible alternative source of energy. The successful completion of the development and transfer of emerging low-cost technologies into a fully commercialized status are identified as the means to the realization of this option's full potential. The DOE National Photovoltaics Program, a significant sponsor of PV R&D, expects both flat-plate and concentrator collectors to meet established cost targets. Citing the DOE large flat-plate grid-connected system project of the Sacramento Municipal Utility District, current technology modules priced at near $5/Wp (1983 dollars) are steadily reducing costs. A recent DOE study suggests that PV-generated electricity produced at a 30-year levelized cost of 15 cents per kWh would represent a viable energy supply alternative for the nation.

Power Budget Analysis for High Altitude Airships

NASA Technical Reports Server (NTRS)

Choi, Sang H.; Elliott, James R.; King, Glen C.

2006-01-01

The High Altitude Airship (HAA) has various potential applications and mission scenarios that require onboard energy harvesting and power distribution systems. The energy source considered for the HAA s power budget is solar photon energy that allows the use of either photovoltaic (PV) cells or advanced thermoelectric (ATE) converters. Both PV cells and an ATE system utilizing high performance thermoelectric materials were briefly compared to identify the advantages of ATE for HAA applications in this study. The ATE can generate a higher quantity of harvested energy than PV cells by utilizing the cascaded efficiency of a three-staged ATE in a tandem mode configuration. Assuming that each stage of ATE material has the figure of merit of 5, the cascaded efficiency of a three-staged ATE system approaches the overall conversion efficiency greater than 60%. Based on this estimated efficiency, the configuration of a HAA and the power utility modules are defined.

Power Generation Potential and Cost of a Roof Top Solar PV System in Kathmandu, Nepal

NASA Astrophysics Data System (ADS)

Sanjel, N.; Zhand, A.

2017-12-01

The paper presents a comparative study of the 3 most used solar PV module technologies in Nepal, which are Si-mono-crystalline, Si-poly-crystalline and Si-amorphous. The aim of the paper is to present and discuss the recorded Global Solar Radiation, received in the Kathmandu valley by three different, Si-mono-crystalline, Si-poly-crystalline and Si-amorphous calibrated solar cell pyranometers and to propose the best-suited solar PV module technology for roof top solar PV systems inside the Kathmandu valley. Data recorded over the course of seven months, thus covering most of the seasonal meteorological conditions determining Kathmandu valley's global solar radiation reception are presented. The results indicate that the Si-amorphous pyranometer captured 1.56% more global solar radiation than the Si-mono-crystalline and 18.4% more than Si-poly-crystalline pyranometer over the course of seven months. Among the three pyranometer technologies the maximum and minimum cell temperature was measured by the Si-mono-crystalline pyranometer. Following the technical data and discussion, an economical analysis, using the versatile software tool PVSYST V5.01is used to calculate the life cycle costs of a 1kW roof top solar PV RAPS system, with battery storage, and a 1kW roof top solar PV grid connected system with no energy storage facility, through simulations, using average recorded global solar radiation data for the KTM valley and investigated market values for each solar PV module and peripheral equipment costs.

The DoE method as an efficient tool for modeling the behavior of monocrystalline Si-PV module

NASA Astrophysics Data System (ADS)

Kessaissia, Fatma Zohra; Zegaoui, Abdallah; Boutoubat, Mohamed; Allouache, Hadj; Aillerie, Michel; Charles, Jean-Pierre

2018-05-01

The objective of this paper is to apply the Design of Experiments (DoE) method to study and to obtain a predictive model of any marketed monocrystalline photovoltaic (mc-PV) module. This technique allows us to have a mathematical model that represents the predicted responses depending upon input factors and experimental data. Therefore, the DoE model for characterization and modeling of mc-PV module behavior can be obtained by just performing a set of experimental trials. The DoE model of the mc-PV panel evaluates the predictive maximum power, as a function of irradiation and temperature in a bounded domain of study for inputs. For the mc-PV panel, the predictive model for both one level and two levels were developed taking into account both influences of the main effect and the interactive effects on the considered factors. The DoE method is then implemented by developing a code under Matlab software. The code allows us to simulate, characterize, and validate the predictive model of the mc-PV panel. The calculated results were compared to the experimental data, errors were estimated, and an accurate validation of the predictive models was evaluated by the surface response. Finally, we conclude that the predictive models reproduce the experimental trials and are defined within a good accuracy.

Solar dynamic power for Space Station Freedom

NASA Technical Reports Server (NTRS)

Labus, Thomas L.; Secunde, Richard R.; Lovely, Ronald G.

1989-01-01

The Space Station Freedom Program is presently planned to consist of two phases. At the completion of Phase 1, Freedom's manned base will consist of a transverse boom with attached manned modules and 75 kW of available electric power supplied by photovoltaic (PV) power sources. In Phase 2, electric power available to the manned base will be increased to 125 kW by the addition of two solar dynamic (SD) power modules, one at each end of the transverse boom. Power for manned base growth beyond Phase 2 will be supplied by additional SD modules. Studies show that SD power for the growth eras will result in life cycle cost savings of $3 to $4 billion when compared to PV-supplied power. In the SD power modules for Space Station Freedom, an offset parabolic concentrator collects and focuses solar energy into a heat receiver. To allow full power operation over the entire orbit, the receiver includes integral thermal energy storage by means of the heat of fusion of a salt mixture. Thermal energy is removed from the receiver and converted to electrical energy by a power conversion unit (PCU) which includes a closed brayton cycle (CBC) heat engine and an alternator. The receiver/PCU/radiator combination will be completely assembled and charged with gas and cooling fluid on earth before launch to orbit. The concentrator subassemblies will be pre-aligned and stowed in the orbiter bay before launch. On orbit, the receiver/PCU/radiator assembly will be installed as a unit. The pre-aligned concentrator panels will then be latched together and the total concentrator attached to the receiver/PCU/radiator by the astronauts. After final electric connections are made and checkout is complete, the SD power module will be ready for operation.

Solar dynamic power for space station freedom

NASA Technical Reports Server (NTRS)

Labus, Thomas L.; Secunde, Richard R.; Lovely, Ronald G.

1989-01-01

The Space Station Freedom Program is presently planned to consist of two phases. At the completion of Phase 1, Freedom's manned base will consist of a transverse boom with attached manned modules and 75 kW of available electric power supplied by photovoltaic (PV) power sources. In Phase 2, electric power available to the manned base will be increased to 125 kW by the addition of two solar dynamic (SD) power modules, one at each end of the transverse boom. Power for manned base growth beyond Phase 2 will be supplied by additional SD modules. Studies show that SD power for the growth eras will result in life cycle cost savings of $3 to $4 billion when compared to PV-supplied power. In the SD power modules for Space Station Freedom, an offset parabolic concentrator collects and focuses solar energy into a heat receiver. To allow full power operation over the entire orbit, the receiver includes integral thermal energy storage by means of the heat of fusion of a salt mixture. Thermal energy is removed from the receiver and converted to electrical energy by a power conversion unit (PCU) which includes a closed brayton cycle (CBC) heat engine and an alternator. The receiver/PCU/radiator combination will be completely assembled and charged with gas and cooling fluid on Earth before launch to orbit. The concentrator subassemblies will be pre-aligned and stowed in the orbiter bay before launch. On orbit, the receiver/PCU/radiator assembly will be installed as a unit. The pre-aligned concentrator panels will then be latched together and the total concentrator attached to the receiver/PCU/radiator by the astronauts. After final electric connections are made and checkout is complete, the SD power module will be ready for operation.

PV Module Reliability Workshop | Photovoltaic Research | NREL

Science.gov Websites

-year old PV system in Quebec, Canada-Alex Bradley, Tanya Dhir, Yves Poissant Solar panel design factors PV Module Reliability Workshop PV Module Reliability Workshop Tuesday, February 24, 2015 Chair : Michael Kempe The 2015 PV Module Reliability Workshop (PVMRW) continued in the tradition of this annual

Outdoor Performance Analysis of a Photovoltaic Thermal (PVT) Collector with Jet Impingement and Compound Parabolic Concentrator (CPC)

PubMed Central

Jaaz, Ahed Hameed; Hasan, Husam Abdulrasool; Sopian, Kamaruzzaman; Kadhum, Abdul Amir H.; Gaaz, Tayser Sumer

2017-01-01

This paper discusses the effect of jet impingement of water on a photovoltaic thermal (PVT) collector and compound parabolic concentrators (CPC) on electrical efficiency, thermal efficiency and power production of a PVT system. A prototype of a PVT solar water collector installed with a jet impingement and CPC has been designed, fabricated and experimentally investigated. The efficiency of the system can be improved by using jet impingement of water to decrease the temperature of the solar cells. The electrical efficiency and power output are directly correlated with the mass flow rate. The results show that electrical efficiency was improved by 7% when using CPC and jet impingement cooling in a PVT solar collector at 1:00 p.m. (solar irradiance of 1050 W/m2 and an ambient temperature of 33.5 °C). It can also be seen that the power output improved by 36% when using jet impingement cooling with CPC, and 20% without CPC in the photovoltaic (PV) module at 1:30 p.m. The short-circuit current ISC of the PV module experienced an improvement of ~28% when using jet impingement cooling with CPC, and 11.7% without CPC. The output of the PV module was enhanced by 31% when using jet impingement cooling with CPC, and 16% without CPC. PMID:28763048

Outdoor Performance Analysis of a Photovoltaic Thermal (PVT) Collector with Jet Impingement and Compound Parabolic Concentrator (CPC).

PubMed

Jaaz, Ahed Hameed; Hasan, Husam Abdulrasool; Sopian, Kamaruzzaman; Kadhum, Abdul Amir H; Gaaz, Tayser Sumer; Al-Amiery, Ahmed A

2017-08-01

This paper discusses the effect of jet impingement of water on a photovoltaic thermal (PVT) collector and compound parabolic concentrators (CPC) on electrical efficiency, thermal efficiency and power production of a PVT system. A prototype of a PVT solar water collector installed with a jet impingement and CPC has been designed, fabricated and experimentally investigated. The efficiency of the system can be improved by using jet impingement of water to decrease the temperature of the solar cells. The electrical efficiency and power output are directly correlated with the mass flow rate. The results show that electrical efficiency was improved by 7% when using CPC and jet impingement cooling in a PVT solar collector at 1:00 p.m. (solar irradiance of 1050 W/m² and an ambient temperature of 33.5 °C). It can also be seen that the power output improved by 36% when using jet impingement cooling with CPC, and 20% without CPC in the photovoltaic (PV) module at 1:30 p.m. The short-circuit current I SC of the PV module experienced an improvement of ~28% when using jet impingement cooling with CPC, and 11.7% without CPC. The output of the PV module was enhanced by 31% when using jet impingement cooling with CPC, and 16% without CPC.

Apparatuses to support photovoltaic modules

DOEpatents

Ciasulli, John; Jones, Jason

2017-08-22

Methods and apparatuses to support photovoltaic ("PV") modules are described. A saddle bracket has a mounting surface to support one or more PV modules over a tube, a gusset coupled to the mounting surface, and a mounting feature coupled to the gusset to couple to the tube. A grounding washer has a first portion to couple to a support; and a second portion coupled to the first portion to provide a ground path to a PV module. A PV system has a saddle bracket; a PV module over the saddle bracket; and a grounding washer coupled to the saddle bracket and the PV module. Saddle brackets can be coupled to a torque tube at predetermined locations. PV modules can be coupled to the saddle brackets.

Optimal charge control strategies for stationary photovoltaic battery systems

NASA Astrophysics Data System (ADS)

Li, Jiahao; Danzer, Michael A.

2014-07-01

Battery systems coupled to photovoltaic (PV) modules for example fulfill one major function: they locally decouple PV generation and consumption of electrical power leading to two major effects. First, they reduce the grid load, especially at peak times and therewith reduce the necessity of a network expansion. And second, they increase the self-consumption in households and therewith help to reduce energy expenses. For the management of PV batteries charge control strategies need to be developed to reach the goals of both the distribution system operators and the local power producer. In this work optimal control strategies regarding various optimization goals are developed on the basis of the predicted household loads and PV generation profiles using the method of dynamic programming. The resulting charge curves are compared and essential differences discussed. Finally, a multi-objective optimization shows that charge control strategies can be derived that take all optimization goals into account.

Energy harvesting using TEG and PV cell for low power application

NASA Astrophysics Data System (ADS)

Tawil, Siti Nooraya Mohd; Zainal, Mohd Zulkarnain

2018-02-01

A thermoelectric generator (TEG) module and photovoltaic cell (PV) were utilized to harvest energy from temperature gradients of heat sources from ambient heat and light of sun. The output of TEG and PV were connected to a power management circuit consist of step-up dc-dc converter in order to increase the output voltage to supply a low power application such as wireless communication module and the photovoltaic cell for charging an energy storage element in order to switch on a fan for cooling system of the thermoelectric generator. A switch is used as a selector to choose the input of source either from photovoltaic cell or thermoelectric generator to switch on DC-DC step-up converter. In order to turn on the DC-DC step-up converter, the input must be greater than 3V. The energy harvesting was designed so that it can be used continuously and portable anywhere. Multiple sources used in this energy harvesting system is to ensure the system can work in whatever condition either in good weather or not good condition of weather. This energy harvesting system has the potential to be used in military operation and environment that require sustainability of energy resources.

Pressure-equalizing PV assembly and method

DOEpatents

Dinwoodie, Thomas L.

2004-10-26

Each PV assembly of an array of PV assemblies comprises a base, a PV module and a support assembly securing the PV module to a position overlying the upper surface of the base. Vents are formed through the base. A pressure equalization path extends from the outer surface of the PV module, past the PV module, to and through at least one of the vents, and to the lower surface of the base to help reduce wind uplift forces on the PV assembly. The PV assemblies may be interengaged, such as by interengaging the bases of adjacent PV assemblies. The base may include a main portion and a cover and the bases of adjacent PV assemblies may be interengaged by securing the covers of adjacent bases together.

Solar concentrator modules with silicone-on-glass Fresnel lens panels and multijunction cells.

PubMed

Rumyantsev, Valery D

2010-04-26

High-efficiency multijunction (MJ) solar cells, being very expensive to manufacture, should only be used in combination with solar concentrators in terrestrial applications. An essential cost reduction of electric power produced by photovoltaic (PV) installations with MJ cells, may be expected by the creation of highly-effective, but inexpensive, elements for optical concentration and sun tracking. This article is an overview of the corresponding approach under development at the Ioffe Physical Technical Institute. The approach to R&D of the solar PV modules is based on the concepts of sunlight concentration by small-aperture area Fresnel lenses and "all-glass" module design. The small-aperture area lenses are arranged as a panel with silicone-on-glass structure where the glass plate serves as the front surface of a module. In turn, high-efficiency InGaP/(In)GaAs/Ge cells are arranged on a rear module panel mounted on a glass plate which functions as a heat sink and integrated protective cover for the cells. The developed PV modules and sun trackers are characterized by simple design, and are regarded as the prototypes for further commercialization.

Solar Photovoltaic DC Systems: Basics and Safety: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

McNutt, Peter F; Sekulic, William R; Dreifuerst, Gary

Solar Photovoltaic (PV) systems are common and growing with 42.4 GW installed capacity in U.S. (almost 15 GW added in 2016). This paper will help electrical workers, and emergency responders understand the basic operating principles and hazards of PV DC arrays. We briefly discuss the following aspects of solar photovoltaic (PV) DC systems: the effects of solar radiation and temperature on output power; PV module testing standards; common system configurations; a simple PV array sizing example; NEC guidelines and other safety features; DC array commissioning, periodic maintenance and testing; arc-flash hazard potential; how electrical workers and emergency responders can andmore » do work safely around PV arrays; do moonlight and artificial lighting pose a real danger; typical safe operating procedures; and other potential DC-system hazards to be aware of. We also present some statistics on PV DC array electrical incidents and injuries. Safe PV array operation is possible with a good understanding of PV DC arrays basics and having good safe operating procedures in place.« less

Module Embedded Micro-inverter Smart Grid Ready Residential Solar Electric System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Agamy, Mohammed

The “Module Embedded Micro-inverter Smart Grid Ready Residential Solar Electric System” program is focused on developing innovative concepts for residential photovoltaic (PV) systems with the following objectives: to create an Innovative micro-inverter topology that reduces the cost from the best in class micro-inverter and provides high efficiency (>96% CEC - California Energy Commission), and 25+ year warranty, as well as reactive power support; integrate micro-inverter and PV module to reduce system price by at least $0.25/W through a) accentuating dual use of the module metal frame as a large area heat spreader reducing operating temperature, and b) eliminating redundant wiringmore » and connectors; and create micro-inverter controller handles smart grid and safety functions to simplify implementation and reduce cost.« less

The effect of material matching on the stress-induced power degradation for light-redirecting-ribbon-based silicon photovoltaic modules

NASA Astrophysics Data System (ADS)

Gou, X. F.; Zhuang, H.; Zhu, J.; Li, X. Y.

2018-01-01

Light redirecting ribbons (LRR) have recently been adopted in crystalline silicon modules in PV industry. The introduction of this LRR may bring additional stress at the boundary of the busbar/wafer contact, which may probably lead to higher power loss after aging. The thermal cycle and electroluminescence (EL) test are employed in this work to investigate this stress-induced power degradation for LRR-based crystalline silicon modules. The obtained results demonstrate that with increase in the thickness of the EVA encapsulant or the decrease in the thickness of the LRR, the power degradation induced by stress can be effectively diminished.

A state-of-the-art compact SiC photovoltaic inverter with maximum power point tracking function

NASA Astrophysics Data System (ADS)

Ando, Yuji; Oku, Takeo; Yasuda, Masashi; Ushijima, Kazufumi; Matsuo, Hiroshi; Murozono, Mikio

2018-01-01

We have developed a 150-W SiC-based photovoltaic (PV)-inverter with the maximum power point tracking (MPPT) function. The newly developed inverter achieved a state-of-the-art combination of the weight (0.79 kg) and the volume (790 mm3) as a 150-250 W class PV-inverter. As compared to the original version that we have previously reported, the weight and volume were decreased by 37% and 38%, respectively. This compactness originated from the optimized circuit structure and the increased density of a wiring circuit. Conversion efficiencies of the MPPT charge controller and the direct current (DC)-alternating current (AC) converter reached 96.4% and 87.6%, respectively. These efficiency values are comparable to those for the original version. We have developed a PV power generation system consisting of this inverter, a spherical Si solar cell module, and a 15-V Li-ion laminated battery. The total weight of the system was below 6 kg. The developed system exhibited stable output power characteristics, even when the weather conditions were fluctuated. These compactness, high efficiencies, and excellent stability clearly indicated the feasibility of SiC power devices even for sub-kW class PV power generation systems.

Numerical investigation of the thermal and electrical performances for combined solar photovoltaic/thermal (PV/T) modules based on internally extruded fin flow channel

NASA Astrophysics Data System (ADS)

Deng, Y. C.; Li, Q. P.; Wang, G. J.

2017-11-01

A solar photovoltaic/thermal (PV/T) module based on internally extruded fin flow channel was investigated numerically in this paper. First of all, the structures of the thin plate heat exchanger and the PV/T module were presented. Then, a numerical model of the PV/T module considering solar irradiation, fluid flow and heat transfer was developed to analyze the performance of the module. Finally, the steady electrical and thermal efficiencies of the PV/T module at different inlet water temperatures and mass flow rates were achieved. These numerical results supply theory basis for practical application of the PV/T module.

Pressure equalizing photovoltaic assembly and method

DOEpatents

Dinwoodie, Thomas L [Piedmont, CA

2003-05-27

Each PV assembly of an array of PV assemblies comprises a base, a PV module and a support assembly securing the PV module to a position overlying the upper surface of the base. Vents are formed through the base. A pressure equalization path extends from the outer surface of the PV module, past the peripheral edge of the PV module, to and through at least one of the vents, and to the lower surface of the base to help reduce wind uplift forces on the PV assembly. The PV assemblies may be interengaged, such as by interengaging the bases of adjacent PV assemblies. The base may include a main portion and a cover and the bases of adjacent PV assemblies may be interengaged by securing the covers of adjacent bases together.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moslehi, Salim; Reddy, T. Agami; Katipamula, Srinivas

This research was undertaken to evaluate different inverse models for predicting power output of solar photovoltaic (PV) systems under different practical scenarios. In particular, we have investigated whether PV power output prediction accuracy can be improved if module/cell temperature was measured in addition to climatic variables, and also the extent to which prediction accuracy degrades if solar irradiation is not measured on the plane of array but only on a horizontal surface. We have also investigated the significance of different independent or regressor variables, such as wind velocity and incident angle modifier in predicting PV power output and cell temperature.more » The inverse regression model forms have been evaluated both in terms of their goodness-of-fit, and their accuracy and robustness in terms of their predictive performance. Given the accuracy of the measurements, expected CV-RMSE of hourly power output prediction over the year varies between 3.2% and 8.6% when only climatic data are used. Depending on what type of measured climatic and PV performance data is available, different scenarios have been identified and the corresponding appropriate modeling pathways have been proposed. The corresponding models are to be implemented on a controller platform for optimum operational planning of microgrids and integrated energy systems.« less

The application of the Luus-Jaakola direct search method to the optimization of a hybrid renewable energy system

NASA Astrophysics Data System (ADS)

Jatzeck, Bernhard Michael

2000-10-01

The application of the Luus-Jaakola direct search method to the optimization of stand-alone hybrid energy systems consisting of wind turbine generators (WTG's), photovoltaic (PV) modules, batteries, and an auxiliary generator was examined. The loads for these systems were for agricultural applications, with the optimization conducted on the basis of minimum capital, operating, and maintenance costs. Five systems were considered: two near Edmonton, Alberta, and one each near Lethbridge, Alberta, Victoria, British Columbia, and Delta, British Columbia. The optimization algorithm used hourly data for the load demand, WTG output power/area, and PV module output power. These hourly data were in two sets: seasonal (summer and winter values separated) and total (summer and winter values combined). The costs for the WTG's, PV modules, batteries, and auxiliary generator fuel were full market values. To examine the effects of price discounts or tax incentives, these values were lowered to 25% of the full costs for the energy sources and two-thirds of the full cost for agricultural fuel. Annual costs for a renewable energy system depended upon the load, location, component costs, and which data set (seasonal or total) was used. For one Edmonton load, the cost for a renewable energy system consisting of 27.01 m2 of WTG area, 14 PV modules, and 18 batteries (full price, total data set) was 6873/year. For Lethbridge, a system with 22.85 m2 of WTG area, 47 PV modules, and 5 batteries (reduced prices, seasonal data set) cost 2913/year. The performance of renewable energy systems based on the obtained results was tested in a simulation using load and weather data for selected days. Test results for one Edmonton load showed that the simulations for most of the systems examined ran for at least 17 hours per day before failing due to either an excessive load on the auxiliary generator or a battery constraint being violated. Additional testing indicated that increasing the generator capacity and reducing the maximum allowed battery charge current during the time of the day at which these failures occurred allowed the simulation to successfully operate.

Indoor Soiling Method and Outdoor Statistical Risk Analysis of Photovoltaic Power Plants

NASA Astrophysics Data System (ADS)

Rajasekar, Vidyashree

This is a two-part thesis. Part 1 presents an approach for working towards the development of a standardized artificial soiling method for laminated photovoltaic (PV) cells or mini-modules. Construction of an artificial chamber to maintain controlled environmental conditions and components/chemicals used in artificial soil formulation is briefly explained. Both poly-Si mini-modules and a single cell mono-Si coupons were soiled and characterization tests such as I-V, reflectance and quantum efficiency (QE) were carried out on both soiled, and cleaned coupons. From the results obtained, poly-Si mini-modules proved to be a good measure of soil uniformity, as any non-uniformity present would not result in a smooth curve during I-V measurements. The challenges faced while executing reflectance and QE characterization tests on poly-Si due to smaller size cells was eliminated on the mono-Si coupons with large cells to obtain highly repeatable measurements. This study indicates that the reflectance measurements between 600-700 nm wavelengths can be used as a direct measure of soil density on the modules. Part 2 determines the most dominant failure modes of field aged PV modules using experimental data obtained in the field and statistical analysis, FMECA (Failure Mode, Effect, and Criticality Analysis). The failure and degradation modes of about 744 poly-Si glass/polymer frameless modules fielded for 18 years under the cold-dry climate of New York was evaluated. Defect chart, degradation rates (both string and module levels) and safety map were generated using the field measured data. A statistical reliability tool, FMECA that uses Risk Priority Number (RPN) is used to determine the dominant failure or degradation modes in the strings and modules by means of ranking and prioritizing the modes. This study on PV power plants considers all the failure and degradation modes from both safety and performance perspectives. The indoor and outdoor soiling studies were jointly performed by two Masters Students, Sravanthi Boppana and Vidyashree Rajasekar. This thesis presents the indoor soiling study, whereas the other thesis presents the outdoor soiling study. Similarly, the statistical risk analyses of two power plants (model J and model JVA) were jointly performed by these two Masters students. Both power plants are located at the same cold-dry climate, but one power plant carries framed modules and the other carries frameless modules. This thesis presents the results obtained on the frameless modules.

Concentrator photovoltaic module architectures with capabilities for capture and conversion of full global solar radiation

PubMed Central

Lee, Kyu-Tae; Yao, Yuan; He, Junwen; Fisher, Brent; Sheng, Xing; Lumb, Matthew; Xu, Lu; Anderson, Mikayla A.; Scheiman, David; Han, Seungyong; Kang, Yongseon; Gumus, Abdurrahman; Bahabry, Rabab R.; Lee, Jung Woo; Paik, Ungyu; Bronstein, Noah D.; Alivisatos, A. Paul; Meitl, Matthew; Burroughs, Scott; Hussain, Muhammad Mustafa; Lee, Jeong Chul; Nuzzo, Ralph G.; Rogers, John A.

2016-01-01

Emerging classes of concentrator photovoltaic (CPV) modules reach efficiencies that are far greater than those of even the highest performance flat-plate PV technologies, with architectures that have the potential to provide the lowest cost of energy in locations with high direct normal irradiance (DNI). A disadvantage is their inability to effectively use diffuse sunlight, thereby constraining widespread geographic deployment and limiting performance even under the most favorable DNI conditions. This study introduces a module design that integrates capabilities in flat-plate PV directly with the most sophisticated CPV technologies, for capture of both direct and diffuse sunlight, thereby achieving efficiency in PV conversion of the global solar radiation. Specific examples of this scheme exploit commodity silicon (Si) cells integrated with two different CPV module designs, where they capture light that is not efficiently directed by the concentrator optics onto large-scale arrays of miniature multijunction (MJ) solar cells that use advanced III–V semiconductor technologies. In this CPV+ scheme (“+” denotes the addition of diffuse collector), the Si and MJ cells operate independently on indirect and direct solar radiation, respectively. On-sun experimental studies of CPV+ modules at latitudes of 35.9886° N (Durham, NC), 40.1125° N (Bondville, IL), and 38.9072° N (Washington, DC) show improvements in absolute module efficiencies of between 1.02% and 8.45% over values obtained using otherwise similar CPV modules, depending on weather conditions. These concepts have the potential to expand the geographic reach and improve the cost-effectiveness of the highest efficiency forms of PV power generation. PMID:27930331

Concentrator photovoltaic module architectures with capabilities for capture and conversion of full global solar radiation

NASA Astrophysics Data System (ADS)

Lee, Kyu-Tae; Yao, Yuan; He, Junwen; Fisher, Brent; Sheng, Xing; Lumb, Matthew; Xu, Lu; Anderson, Mikayla A.; Scheiman, David; Han, Seungyong; Kang, Yongseon; Gumus, Abdurrahman; Bahabry, Rabab R.; Lee, Jung Woo; Paik, Ungyu; Bronstein, Noah D.; Alivisatos, A. Paul; Meitl, Matthew; Burroughs, Scott; Mustafa Hussain, Muhammad; Lee, Jeong Chul; Nuzzo, Ralph G.; Rogers, John A.

2016-12-01

Emerging classes of concentrator photovoltaic (CPV) modules reach efficiencies that are far greater than those of even the highest performance flat-plate PV technologies, with architectures that have the potential to provide the lowest cost of energy in locations with high direct normal irradiance (DNI). A disadvantage is their inability to effectively use diffuse sunlight, thereby constraining widespread geographic deployment and limiting performance even under the most favorable DNI conditions. This study introduces a module design that integrates capabilities in flat-plate PV directly with the most sophisticated CPV technologies, for capture of both direct and diffuse sunlight, thereby achieving efficiency in PV conversion of the global solar radiation. Specific examples of this scheme exploit commodity silicon (Si) cells integrated with two different CPV module designs, where they capture light that is not efficiently directed by the concentrator optics onto large-scale arrays of miniature multijunction (MJ) solar cells that use advanced III-V semiconductor technologies. In this CPV+ scheme (“+” denotes the addition of diffuse collector), the Si and MJ cells operate independently on indirect and direct solar radiation, respectively. On-sun experimental studies of CPV+ modules at latitudes of 35.9886° N (Durham, NC), 40.1125° N (Bondville, IL), and 38.9072° N (Washington, DC) show improvements in absolute module efficiencies of between 1.02% and 8.45% over values obtained using otherwise similar CPV modules, depending on weather conditions. These concepts have the potential to expand the geographic reach and improve the cost-effectiveness of the highest efficiency forms of PV power generation.

Concentrator photovoltaic module architectures with capabilities for capture and conversion of full global solar radiation.

PubMed

Lee, Kyu-Tae; Yao, Yuan; He, Junwen; Fisher, Brent; Sheng, Xing; Lumb, Matthew; Xu, Lu; Anderson, Mikayla A; Scheiman, David; Han, Seungyong; Kang, Yongseon; Gumus, Abdurrahman; Bahabry, Rabab R; Lee, Jung Woo; Paik, Ungyu; Bronstein, Noah D; Alivisatos, A Paul; Meitl, Matthew; Burroughs, Scott; Hussain, Muhammad Mustafa; Lee, Jeong Chul; Nuzzo, Ralph G; Rogers, John A

2016-12-20

Emerging classes of concentrator photovoltaic (CPV) modules reach efficiencies that are far greater than those of even the highest performance flat-plate PV technologies, with architectures that have the potential to provide the lowest cost of energy in locations with high direct normal irradiance (DNI). A disadvantage is their inability to effectively use diffuse sunlight, thereby constraining widespread geographic deployment and limiting performance even under the most favorable DNI conditions. This study introduces a module design that integrates capabilities in flat-plate PV directly with the most sophisticated CPV technologies, for capture of both direct and diffuse sunlight, thereby achieving efficiency in PV conversion of the global solar radiation. Specific examples of this scheme exploit commodity silicon (Si) cells integrated with two different CPV module designs, where they capture light that is not efficiently directed by the concentrator optics onto large-scale arrays of miniature multijunction (MJ) solar cells that use advanced III-V semiconductor technologies. In this CPV + scheme ("+" denotes the addition of diffuse collector), the Si and MJ cells operate independently on indirect and direct solar radiation, respectively. On-sun experimental studies of CPV + modules at latitudes of 35.9886° N (Durham, NC), 40.1125° N (Bondville, IL), and 38.9072° N (Washington, DC) show improvements in absolute module efficiencies of between 1.02% and 8.45% over values obtained using otherwise similar CPV modules, depending on weather conditions. These concepts have the potential to expand the geographic reach and improve the cost-effectiveness of the highest efficiency forms of PV power generation.

A Practical Irradiance Model for Bifacial PV Modules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marion, Bill; MacAlpine, Sara; Deline, Chris

2017-06-21

A model, suitable for a row or multiple rows of photovoltaic (PV) modules, is presented for estimating the backside irradiance for bifacial PV modules. The model, which includes the effects of shading by the PV rows, is based on the use of configuration factors to determine the fraction of a source of irradiance that is received by the backside of the PV module. Backside irradiances are modeled along the sloped height of the PV module, but assumed not to vary along the length of the PV row. The backside irradiances are corrected for angle-of-incidence losses and may be added tomore » the front side irradiance to determine the total irradiance resource for the PV cell. Model results are compared with the measured backside irradiances for NREL and Sandia PV systems, and with results when using ray tracing software.« less

A Practical Irradiance Model for Bifacial PV Modules: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marion, Bill; MacAlpine, Sara; Deline, Chris

2017-06-15

A model, suitable for a row or multiple rows of photovoltaic (PV) modules, is presented for estimating the backside irradiance for bifacial PV modules. The model, which includes the effects of shading by the PV rows, is based on the use of configuration factors (CFs) to determine the fraction of a source of irradiance that is received by the backside of the PV module. Backside irradiances are modeled along the sloped height of the PV module, but assumed not to vary along the length of the PV row. The backside irradiances are corrected for angle-of-incidence losses and may be addedmore » to the front side irradiance to determine the total irradiance resource for the PV cell. Model results are compared with the measured backside irradiances for NREL and Sandia PV systems, and with results when using the RADIANCE ray tracing program.« less

Electrochemical wastewater treatment directly powered by photovoltaic panels: electrooxidation of a dye-containing wastewater.

PubMed

Valero, David; Ortiz, Juan M; Expósito, Eduardo; Montiel, Vicente; Aldaz, Antonio

2010-07-01

Electrochemical technologies have proved to be useful for the treatment of wastewater, but to enhance their green characteristics it seems interesting to use a green electric energy such as that provided by photovoltaic (PV) cells, which are actually under active research to decrease the economic cost of solar kW. The aim of this work is to demonstrate the feasibility and utility of using an electrooxidation system directly powered by a photovoltaic array for the treatment of a wastewater. The experimental system used was an industrial electrochemical filter press reactor and a 40-module PV array. The influence on the degradation of a dye-containing solution (Remazol RB 133) of different experimental parameters such as the PV array and electrochemical reactor configurations has been studied. It has been demonstrated that the electrical configuration of the PV array has a strong influence on the optimal use of the electric energy generated. The optimum PV array configuration changes with the intensity of the solar irradiation, the conductivity of the solution, and the concentration of pollutant in the wastewater. A useful and effective methodology to adjust the EO-PV system operation conditions to the wastewater treatment is proposed.

Simulation and optimum design of hybrid solar-wind and solar-wind-diesel power generation systems

NASA Astrophysics Data System (ADS)

Zhou, Wei

Solar and wind energy systems are considered as promising power generating sources due to its availability and topological advantages in local power generations. However, a drawback, common to solar and wind options, is their unpredictable nature and dependence on weather changes, both of these energy systems would have to be oversized to make them completely reliable. Fortunately, the problems caused by variable nature of these resources can be partially overcome by integrating these two resources in a proper combination to form a hybrid system. However, with the increased complexity in comparison with single energy systems, optimum design of hybrid system becomes more complicated. In order to efficiently and economically utilize the renewable energy resources, one optimal sizing method is necessary. This thesis developed an optimal sizing method to find the global optimum configuration of stand-alone hybrid (both solar-wind and solar-wind-diesel) power generation systems. By using Genetic Algorithm (GA), the optimal sizing method was developed to calculate the system optimum configuration which offers to guarantee the lowest investment with full use of the PV array, wind turbine and battery bank. For the hybrid solar-wind system, the optimal sizing method is developed based on the Loss of Power Supply Probability (LPSP) and the Annualized Cost of System (ACS) concepts. The optimization procedure aims to find the configuration that yields the best compromise between the two considered objectives: LPSP and ACS. The decision variables, which need to be optimized in the optimization process, are the PV module capacity, wind turbine capacity, battery capacity, PV module slope angle and wind turbine installation height. For the hybrid solar-wind-diesel system, minimization of the system cost is achieved not only by selecting an appropriate system configuration, but also by finding a suitable control strategy (starting and stopping point) of the diesel generator. The optimal sizing method was developed to find the system optimum configuration and settings that can achieve the custom-required Renewable Energy Fraction (fRE) of the system with minimum Annualized Cost of System (ACS). Du to the need for optimum design of the hybrid systems, an analysis of local weather conditions (solar radiation and wind speed) was carried out for the potential installation site, and mathematical simulation of the hybrid systems' components was also carried out including PV array, wind turbine and battery bank. By statistically analyzing the long-term hourly solar and wind speed data, Hong Kong area is found to have favorite solar and wind power resources compared with other areas, which validates the practical applications in Hong Kong and Guangdong area. Simulation of PV array performance includes three main parts: modeling of the maximum power output of the PV array, calculation of the total solar radiation on any tilted surface with any orientations, and PV module temperature predictions. Five parameters are introduced to account for the complex dependence of PV array performance upon solar radiation intensities and PV module temperatures. The developed simulation model was validated by using the field-measured data from one existing building-integrated photovoltaic system (BIPV) in Hong Kong, and good simulation performance of the model was achieved. Lead-acid batteries used in hybrid systems operate under very specific conditions, which often cause difficulties to predict when energy will be extracted from or supplied to the battery. In this thesis, the lead-acid battery performance is simulated by three different characteristics: battery state of charge (SOC), battery floating charge voltage and the expected battery lifetime. Good agreements were found between the predicted values and the field-measured data of a hybrid solar-wind project. At last, one 19.8kW hybrid solar-wind power generation project, designed by the optimal sizing method and set up to supply power for a telecommunication relay station on a remote island of Guangdong province, was studied. Simulation and experimental results about the operating performances and characteristics of the hybrid solar-wind project have demonstrated the feasibility and accuracy of the recommended optimal sizing method developed in this thesis.

Battery Reinitialization of the Photovoltaic Module of the International Space Station

NASA Technical Reports Server (NTRS)

Hajela, Gyan; Cohen, Fred; Dalton, Penni

2002-01-01

The photovoltaic (PV) module on the International Space Station (ISS) has been operating since November 2000 and supporting electric power demands of the ISS and its crew of three. The PV module contains photovoltaic arrays that convert solar energy to electrical power and an integrated equipment assembly (IEA) that houses electrical hardware and batteries for electric power regulation and storage. Each PV module contains two independent power channels for fault tolerance. Each power channel contains three batteries in parallel to meet its performance requirements and for fault tolerance. Each battery consists of 76 Ni-Hydrogen (Ni-H2) cells in series. These 76 cells are contained in two orbital replaceable units (ORU) that are connected in series. On-orbit data are monitored and trended to ensure that all hardware is operating normally. Review of on-orbit data showed that while five batteries are operating very well, one is showing signs of mismatched ORUs. The cell pressure in the two ORUs differs by an amount that exceeds the recommended range. The reason for this abnormal behavior may be that the two ORUs have different use history. An assessment was performed and it was determined that capacity of this battery would be limited by the lower pressure ORU. Steps are being taken to reduce this pressure differential before battery capacity drops to the point of affecting its ability to meet performance requirements. As a first step, a battery reinitialization procedure was developed to reduce this pressure differential. The procedure was successfully carried out on-orbit and the pressure differential was reduced to the recommended range. This paper describes the battery performance and the consequences of mismatched ORUs that make a battery. The paper also describes the reinitialization procedure, how it was performed on orbit, and battery performance after the reinitialization. On-orbit data monitoring and trending is an ongoing activity and it will continue as ISS assembly progresses.

Dynamic of small photovoltaic systems

NASA Astrophysics Data System (ADS)

Mehrmann, A.; Kleinkauf, W.; Pigorsch, W.; Steeb, H.

The results of 1.5 yr of field-testing of two photovoltaic (PV) power plants, one equipped with an electrolyzer and H2 storage, are reported. Both systems were interconnected with the grid and featured the PV module, a power conditioning unit, ac and dc load connections, and control units. The rated power of both units was 100 Wp. The system with electrolysis was governed by control laws which maximized the electrolyzer current. The tests underscored the preference for a power conditioning unit, rather than direct output to load connections. A 1 kWp system was developed in a follow-up program and will be tested in concert with electrolysis and interconnection with several grid customers. The program is geared to eventual development of larger units for utility-size applications.

Development of Manufacturing Technology to Accelerate Cost Reduction of Low Concentration and

DOE Office of Scientific and Technical Information (OSTI.GOV)

Detrick, Adam

The purpose of this project was to accelerate deployment of cost-effective US-based manufacturing of Solaria’s unique c-Si module technology. This effort successfully resulted in the development of US-based manufacturing technology to support two highly-differentiated, market leading product platforms. The project was initially predicated on developing Solaria’s low-concentration PV (LCPV) module technology which at the time of the award was uniquely positioned to exceed the SunShot price goal of $0.50/Wp for standard c-Si modules. The Solaria LCPV module is a 2.5x concentrator that leverages proven, high-reliability PV module materials and low silicon cell usage into a technology package that already hadmore » the lowest direct material cost and leading Levelized Cost of Electricity (LCOE). With over 25 MW commercially deployed globally, the Solaria module was well positioned to continue to lead in PV module cost reduction. Throughout the term of the contract, market conditions changed dramatically and so to did Solaria’s product offerings to support this. However, the manufacturing technology developed for the LCPV module was successfully leveraged and optimized to support two new and different product platforms. BIPV “PowerVision” and High-efficiency “PowerXT” modules. The primary barrier to enabling high-volume PV module manufacturing in the US is the high manual labor component in certain unique aspects of our manufacturing process. The funding was used to develop unique manufacturing automation which makes the manual labor components of these key processes more efficient and increase throughput. At the core of Solaria’s product offerings are its unique and proprietary techniques for dicing and re-arranging solar cells into modules with highly-differentiated characteristics that address key gaps in the c-Si market. It is these techniques that were successfully evolved and deployed into US-based manufacturing site with SunShot funding. Today, Solaria is currently positioned to become the market leader with these two technologies over the coming 24 months largely due to the successful innovations of the underlying manufacturing technology. This success will leverage US-based manufacturing technology and the associated US-jobs to support. Solaria views the project as highly successful and a great example of SunShot funding enabling the creating of US jobs and the deployment of ubiquitous solar energy products.« less

Dynamic analysis of combined photovoltaic source and synchronous generator connected to power grid

NASA Astrophysics Data System (ADS)

Mahabal, Divya

In the world of expanding economy and technology, the energy demand is likely to increase even with the global efforts of saving and increasing energy efficiency. Higher oil prices, effects of greenhouse gases, and concerns over other environmental impacts gave way to Distributed Generation (DG). With adequate awareness and support, DG's can meet these rising energy demands at lower prices compared to conventional methods. Extensive research is taking place in different areas like fuel cells, photovoltaic cells, wind turbines, and gas turbines. DG's when connected to a grid increase the overall efficiency of the power grid. It is believed that three-fifth of the world's electricity would account for renewable energy by middle of 21st century. This thesis presents the dynamic analysis of a grid connected photovoltaic (PV) system and synchronous generator. A grid is considered as an infinite bus. The photovol-taic system and synchronous generator act as small scale distributed energy resources. The output of the photovoltaic system depends on the light intensity, temperature, and irradiance levels of sun. The maximum power point tracking and DC/AC converter are also modeled for the photovoltaic system. The PV system is connected to the grid through DC/AC system. Different combinations of PV and synchronous generator are modeled with the grid to study the dynamics of the proposed system. The dynamics of the test system is analyzed by subjecting the system to several disturbances under various conditions. All modules are individually modeled and con-nected using MATLAB/Simulink software package. Results from the study show that, as the penetration of renewable energy sources like PV increases into the power system, the dynamics of the system becomes faster. When considering cases such as load switching, PV cannot deliver more power as the performance of PV depends on environmental conditions. Synchronous generator in power system can produce the required amount of power. As the main aim of this research is to use renewable sources like PV in the system, it is advantageous to use a combination of both PV and synchronous generator in the system.

Evaluation of Data-Driven Models for Predicting Solar Photovoltaics Power Output

DOE PAGES

Moslehi, Salim; Reddy, T. Agami; Katipamula, Srinivas

2017-09-10

This research was undertaken to evaluate different inverse models for predicting power output of solar photovoltaic (PV) systems under different practical scenarios. In particular, we have investigated whether PV power output prediction accuracy can be improved if module/cell temperature was measured in addition to climatic variables, and also the extent to which prediction accuracy degrades if solar irradiation is not measured on the plane of array but only on a horizontal surface. We have also investigated the significance of different independent or regressor variables, such as wind velocity and incident angle modifier in predicting PV power output and cell temperature.more » The inverse regression model forms have been evaluated both in terms of their goodness-of-fit, and their accuracy and robustness in terms of their predictive performance. Given the accuracy of the measurements, expected CV-RMSE of hourly power output prediction over the year varies between 3.2% and 8.6% when only climatic data are used. Depending on what type of measured climatic and PV performance data is available, different scenarios have been identified and the corresponding appropriate modeling pathways have been proposed. The corresponding models are to be implemented on a controller platform for optimum operational planning of microgrids and integrated energy systems.« less

Wavelength-Selective Photovoltaics for Power-generating Greenhouses

NASA Astrophysics Data System (ADS)

Carter, Sue; Loik, Michael; Shugar, David; Corrado, Carley; Wade, Catherine; Alers, Glenn

2014-03-01

While photovoltaic (PV) technologies are being developed that have the potential for meeting the cost target of 0.50/W per module, the cost of installation combined with the competition over land resources could curtail the wide scale deployment needed to generate the Terrawatts per year required to meet the world's electricity demands. To be cost effective, such large scale power generation will almost certainly require PV solar farms to be installed in agricultural and desert areas, thereby competing with food production, crops for biofuels, or the biodiversity of desert ecosystems. This requirement has put the PV community at odds with both the environmental and agricultural groups they would hope to support through the reduction of greenhouse gas emissions. A possible solution to this challenge is the use of wavelength-selective solar collectors, based on luminescent solar concentrators, that transmit wavelengths needed for plant growth while absorbing the remaining portions of the solar spectrum and converting it to power. Costs are reduced through simultaneous use of land for both food and power production, by replacing the PV cells by inexpensive long-lived luminescent materials as the solar absorber, and by integrating the panels directly into existing greenhouse or cold frames. Results on power generation and crop yields for year-long trials done at academic and commercial greenhouse growers in California will be presented.

A Modular Multilevel Converter with Power Mismatch Control for Grid-Connected Photovoltaic Systems

DOE PAGES

Duman, Turgay; Marti, Shilpa; Moonem, M. A.; ...

2017-05-17

A modular multilevel power converter configuration for grid connected photovoltaic (PV) systems is proposed. The converter configuration replaces the conventional bulky line frequency transformer with several high frequency transformers, potentially reducing the balance of systems cost of PV systems. The front-end converter for each port is a neutral-point diode clamped (NPC) multi-level dc-dc dual-active bridge (ML-DAB) which allows maximum power point tracking (MPPT). The integrated high frequency transformer provides the galvanic isolation between the PV and grid side and also steps up the low dc voltage from PV source. Following the ML-DAB stage, in each port, is a NPC inverter.more » N number of NPC inverters’ outputs are cascaded to attain the per-phase line-to-neutral voltage to connect directly to the distribution grid (i.e., 13.8 kV). The cascaded NPC (CNPC) inverters have the inherent advantage of using lower rated devices, smaller filters and low total harmonic distortion required for PV grid interconnection. The proposed converter system is modular, scalable, and serviceable with zero downtime with lower foot print and lower overall cost. A novel voltage balance control at each module based on power mismatch among N-ports, have been presented and verified in simulation. Analysis and simulation results are presented for the N-port converter. The converter performance has also been verified on a hardware prototype.« less

A Modular Multilevel Converter with Power Mismatch Control for Grid-Connected Photovoltaic Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Duman, Turgay; Marti, Shilpa; Moonem, M. A.

A modular multilevel power converter configuration for grid connected photovoltaic (PV) systems is proposed. The converter configuration replaces the conventional bulky line frequency transformer with several high frequency transformers, potentially reducing the balance of systems cost of PV systems. The front-end converter for each port is a neutral-point diode clamped (NPC) multi-level dc-dc dual-active bridge (ML-DAB) which allows maximum power point tracking (MPPT). The integrated high frequency transformer provides the galvanic isolation between the PV and grid side and also steps up the low dc voltage from PV source. Following the ML-DAB stage, in each port, is a NPC inverter.more » N number of NPC inverters’ outputs are cascaded to attain the per-phase line-to-neutral voltage to connect directly to the distribution grid (i.e., 13.8 kV). The cascaded NPC (CNPC) inverters have the inherent advantage of using lower rated devices, smaller filters and low total harmonic distortion required for PV grid interconnection. The proposed converter system is modular, scalable, and serviceable with zero downtime with lower foot print and lower overall cost. A novel voltage balance control at each module based on power mismatch among N-ports, have been presented and verified in simulation. Analysis and simulation results are presented for the N-port converter. The converter performance has also been verified on a hardware prototype.« less

Numerical modeling of uncertainty and variability in the technology, manufacturing, and economics of crystalline silicon photovoltaics

NASA Astrophysics Data System (ADS)

Ristow, Alan H.

2008-10-01

Electricity generated from photovoltaics (PV) promises to satisfy the world's ever-growing thirst for energy without significant pollution and greenhouse gas emissions. At present, however, PV is several times too expensive to compete economically with conventional sources of electricity delivered via the power grid. To ensure long-term success, must achieve cost parity with electricity generated by conventional sources of electricity. This requires detailed understanding of the relationship between technology and economics as it pertains to PV devices and systems. The research tasks of this thesis focus on developing and using four types of models in concert to develop a complete picture of how solar cell technology and design choices affect the quantity and cost of energy produced by PV systems. It is shown in this thesis that high-efficiency solar cells can leverage balance-of-systems (BOS) costs to gain an economic advantage over solar cells with low efficiencies. This advantage is quantified and dubbed the "efficiency premium." Solar cell device models are linked to models of manufacturing cost and PV system performance to estimate both PV system cost and performance. These, in turn, are linked to a model of levelized electricity cost to estimate the per-kilowatt-hour cost of electricity produced by the PV system. A numerical PV module manufacturing cost model is developed to facilitate this analysis. The models and methods developed in this thesis are used to propose a roadmap to high-efficiency multicrystalline-silicon PV modules that achieve cost parity with electricity from the grid. The impact of PV system failures on the cost of electricity is also investigated; from this, a methodology is proposed for improving the reliability of PV inverters.

Integrating DC/DC Conversion with Possible Reconfiguration within Submodule Solar Photovoltaic Systems

NASA Astrophysics Data System (ADS)

Huang, Peter Jen-Hung

This research first proposes a method to merge photovoltaic (PV) cells or PV panels within the internal components DC-DC converters. The purpose of this merged structure is to reconfigure the PV modules between series and parallel connections using high switching frequencies (hundreds of kHz). This leads to multi-levels of voltages and currents that become applied to the output filter of the converter. Further, this research introduces a concept of a switching cell that utilizes the reconfiguration of series and parallel connections in DC-DC converters. The switching occurs at high switching frequency and the switches can be integrated to be within the solar panels or in between the solar cells. The concept is generalized and applied to basic buck and boost topologies. As examples of the new types of converters: reconfigurable PV-buck and PV-boost converter topologies are presented. It is also possible to create other reconfigurable power converters: non-isolated and isolated topologies. Analysis, simulation and experimental verification for the reconfigurable PV-buck and PV-boost converters are presented extensively to illustrate proof of concept. Benefits and drawbacks of the new approach are discussed. The second part of this research proposes to utilize the internal solar cell capacitance and internal solar module wire parasitic inductances to replace the input capacitor and filter inductor in boost derived DC-DC converters for energy harvesting applications. High switching frequency (MHz) hard switched and resonant boost converters are proposed. Their analysis, simulation and experimental prototypes are presented. A specific proof-of-concept application is especially tested for foldable PV panels, which are known for their high internal wire inductance. The experimental converters successfully boost solar module voltage without adding any external input capacitance or filter inductor. Benefits and drawbacks of new proposed PV submodule integrated boost converters are discussed.

Wind effect on PV module temperature: Analysis of different techniques for an accurate estimation.

NASA Astrophysics Data System (ADS)

Schwingshackl, Clemens; Petitta, Marcello; Ernst Wagner, Jochen; Belluardo, Giorgio; Moser, David; Castelli, Mariapina; Zebisch, Marc; Tetzlaff, Anke

2013-04-01

In this abstract a study on the influence of wind to model the PV module temperature is presented. This study is carried out in the framework of the PV-Alps INTERREG project in which the potential of different photovoltaic technologies is analysed for alpine regions. The PV module temperature depends on different parameters, such as ambient temperature, irradiance, wind speed and PV technology [1]. In most models, a very simple approach is used, where the PV module temperature is calculated from NOCT (nominal operating cell temperature), ambient temperature and irradiance alone [2]. In this study the influence of wind speed on the PV module temperature was investigated. First, different approaches suggested by various authors were tested [1], [2], [3], [4], [5]. For our analysis, temperature, irradiance and wind data from a PV test facility at the airport Bolzano (South Tyrol, Italy) from the EURAC Institute of Renewable Energies were used. The PV module temperature was calculated with different models and compared to the measured PV module temperature at the single panels. The best results were achieved with the approach suggested by Skoplaki et al. [1]. Preliminary results indicate that for all PV technologies which were tested (monocrystalline, amorphous, microcrystalline and polycrystalline silicon and cadmium telluride), modelled and measured PV module temperatures show a higher agreement (RMSE about 3-4 K) compared to standard approaches in which wind is not considered. For further investigation the in-situ measured wind velocities were replaced with wind data from numerical weather forecast models (ECMWF, reanalysis fields). Our results show that the PV module temperature calculated with wind data from ECMWF is still in very good agreement with the measured one (R² > 0.9 for all technologies). Compared to the previous analysis, we find comparable mean values and an increasing standard deviation. These results open a promising approach for PV module temperature estimation using meteorological parameters. References: [1] Skoplaki, E. et al., 2008: A simple correlation for the operating temperature of photovoltaic modules of arbitrary mounting, Solar Energy Materials & Solar Cells 92, 1393-1402 [2] Skoplaki, E. et al., 2008: Operating temperature of photovoltaic modules: A survey of pertinent correlations, Renewable Energy 34, 23-29 [3] Koehl, M. et al., 2011: Modeling of the nominal operating cell temperature based on outdoor weathering, Solar Energy Materials & Solar Cells 95, 1638-1646 [4] Mattei, M. et al., 2005: Calculation of the polycrystalline PV module temperature using a simple method of energy balance, Renewable Energy 31, 553-567 [5] Kurtz, S. et al.: Evaluation of high-temperature exposure of rack-mounted photovoltaic modules

Potential-induced degradation in photovoltaic modules: a critical review

DOE PAGES

Luo, Wei; Khoo, Yong Sheng; Hacke, Peter; ...

2016-11-21

Potential-induced degradation (PID) has received considerable attention in recent years due to its detrimental impact on photovoltaic (PV) module performance under field conditions. Both crystalline silicon (c-Si) and thin-film PV modules are susceptible to PID. While extensive studies have already been conducted in this area, the understanding of the PID phenomena is still incomplete and it remains a major problem in the PV industry. Herein, a critical review of the available literature is given to serve as a one-stop source for understanding the current status of PID research. This article also aims to provide an overview of future research pathsmore » to address PID-related issues. This paper consists of three parts. In the first part, the modelling of leakage current paths in the module package is discussed. The PID mechanisms in both c-Si and thin-film PV modules are also comprehensively reviewed. The second part summarizes various test methods to evaluate PV modules for PID. The last part focuses on studies related to PID in the omnipresent p-type c-Si PV modules. The dependence of temperature, humidity and voltage on the progression of PID is examined. Preventive measures against PID at the cell, module and system levels are illustrated. Moreover, PID recovery in standard p-type c-Si PV modules is also studied. Most of the findings from p-type c-Si PV modules are also applicable to other PV module technologies.« less

Investigation of test methods, material properties, and processes for solar cell encapsulants

NASA Technical Reports Server (NTRS)

1984-01-01

Photovoltaic (PV) modules consist of a string of electrically interconnected silicon solar cells capable of producing practical quantities of electrical power when exposed to sunlight. To insure high reliability and long term performance, the functional components of the solar cell module must be adequately protected from the environment by some encapsulation technique. The encapsulation system must provide mechanical support for the cells and corrosion protection for the electrical components. The goal of the program is to identify and develop encapsulation systems consistent with the PV module operating requirements of 30 year life and a target cost of $0.70 per peak watt ($70 per square meter) (1980 dollars). Assuming a module efficiency of ten percent, which is equivalent to a power output of 100 watts per square meter in midday sunlight, the capital cost of the modules may be calculated to be $70.00 per square meter. Out of this cost goal, only 20 percent is available for encapsulation due to the high cost of the cells, interconnects, and other related components. The encapsulation cost allocation may then be stated as $14.00 per square meter, included all coatings, pottant and mechanical supports for the cells.

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

NASA Astrophysics Data System (ADS)

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.

Photovoltaic Subcontract Program

DOE Office of Scientific and Technical Information (OSTI.GOV)

Surek, Thomas; Catalano, Anthony

1993-03-01

This report summarizes the fiscal year (FY) 1992 progress of the subcontracted photovoltaic (PV) research and development (R D) performed under the Photovoltaic Advanced Research and Development Project at the National Renewable Energy Laboratory (NREL)-formerly the Solar Energy Research Institute (SERI). The mission of the national PV program is to develop PV technology for large-scale generation of economically competitive electric power in the United States. The technical sections of the report cover the main areas of the subcontract program: the Crystalline Materials and Advanced Concepts project, the Polycrystalline Thin Films project, Amorphous Silicon Research project, the Photovoltaic Manufacturing Technology (PVMaT)more » project, PV Module and System Performance and Engineering project, and the PV Analysis and Applications Development project. Technical summaries of each of the subcontracted programs provide a discussion of approaches, major accomplishments in FY 1992, and future research directions.« less

Dynamic Performance Comparison for MPPT-PV Systems using Hybrid Pspice/Matlab Simulation

NASA Astrophysics Data System (ADS)

Aouchiche, N.; Becherif, M.; HadjArab, A.; Aitcheikh, M. S.; Ramadan, H. S.; Cheknane, A.

2016-10-01

The power generated by solar photovoltaic (PV) module depends on the surrounding irradiance and temperature. This paper presents a hybrid Matlab™/Pspice™ simulation model of PV system, combined with Cadence software SLPS. The hybridization is performed in order to gain the advantages of both simulation tools such as accuracy and efficiency in both Pspice electronic circuit and Matlab™ mathematical modelling respectively. For this purpose, the PV panel and the boost converter are developed using Pspice™ and hybridized with the mathematical Matlab™ model of maximum power point method controller (MPPT) through SLPS. The main objective is verify the significance of using the proposed hybrid simulation techniques in comparing the different MPPT algorithms such as the perturbation and observation (P&O), incremental of conductance (Inc-Cond) and counter reaction voltage using pilot cell (Pilot-Cell). Various simulations are performed under different atmospheric conditions in order to evaluate the dynamic behaviour for the system under study in terms of stability, efficiency and rapidity.

Experimental grid connected PV system power analysis

NASA Astrophysics Data System (ADS)

Semaoui, Smail; Abdeladim, Kamel; Arab, Amar Hadj; Boulahchich, Saliha; Amrouche, Said Ould; Yassaa, Noureddine

2018-05-01

Almost 80 % of Algerian territory is appropriate for the exploitation of solar energy. The Algerian energetic strategy provides a substantial injection of PV electricity to the national grid. Currently, about 344 MWp of PV arrays which corresponds approximately to 2,34 km2 of module surfaces, are connected on electricity grid over the national territory. The Algerian Northern regions are characterized by strong pollution and high humidity. These phenomena affect the energetic productivity of PV generator. The objective of our study is to analyze experimental grid connected PV system power in coastal locations. Hence, experiments have been conducted on three identical PV systems to determine the electrical performances. Transformer-less inverters are the most attractive for the ground-based photovoltaic (PV) system due to their efficiencies, reduced cost and weight. Besides, the absence of the galvanic isolation generates problems of capacitive leakage current on the AC side and the degradation of the insulation resistance on the DC side of the inverter. In this work, experimental study of the behavior of single-phase inverters without transformers is presented. The main objective of this work is to study the degradation of the insulation resistance at the input of the inverter, and the capacitive leakage current at the output of the inverter. This study was achieved at the CDER on a rainy day of 15/03/2017, on the first PV plant connected to the low voltage network in Algeria. This investigation can help forecasting the PV array energetic production by taking into account natural conditions.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deline, Chris; Meydbray, Jenya; Donovan, Matt

The 2012 NREL report 'Photovoltaic Shading Testbed for Module-Level Power Electronics' provides a standard methodology for estimating the performance benefit of distributed power electronics under partial shading conditions. Since the release of the report, experiments have been conducted for a number of products and for different system configurations. Drawing from these experiences, updates to the test and analysis methods are recommended. Proposed changes in data processing have the benefit of reducing the sensitivity to measurement errors and weather variability, as well as bringing the updated performance score in line with measured and simulated values of the shade recovery benefit ofmore » distributed PV power electronics. Also, due to the emergence of new technologies including sub-module embedded power electronics, the shading method has been extended to include power electronics that operate at a finer granularity than the module level. An update to the method is proposed to account for these emerging technologies that respond to shading differently than module-level devices. The partial shading test remains a repeatable test procedure that attempts to simulate shading situations as would be experienced by typical residential or commercial rooftop photovoltaic (PV) systems. Performance data for multiple products tested using this method are discussed, based on equipment from Enphase, Solar Edge, Maxim Integrated and SMA. In general, the annual recovery of shading losses from the module-level electronics evaluated is 25-35%, with the major difference between different trials being related to the number of parallel strings in the test installation rather than differences between the equipment tested. Appendix D data has been added in this update.« less

Tracking the global maximum power point of PV arrays under partial shading conditions

NASA Astrophysics Data System (ADS)

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 Module Reliability Workshop 2011: February 16-17, 2011

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, S.

2013-11-01

NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

Photovoltaic Module Reliability Workshop 2014: February 25-26, 2014

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, S.

2014-02-01

NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

Photovoltaic Module Reliability Workshop 2013: February 26-27, 2013

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, S.

2013-10-01

NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

Photovoltaic Module Reliability Workshop 2010: February 18-19, 2010

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, J.

2013-11-01

NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

2016 NREL Photovoltaic Module Reliability Workshop

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, Sarah

NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology - both critical goals for moving PV technologies deeper into the electricity marketplace.

2015 NREL Photovoltaic Module Reliability Workshops

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, Sarah

NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

Multi-position photovoltaic assembly

DOEpatents

Dinwoodie, Thomas L.

2003-03-18

The invention is directed to a PV assembly, for use on a support surface, comprising a base, a PV module, a multi-position module support assembly, securing the module to the base at shipping and inclined-use angles, a deflector, a multi-position deflector support securing the deflector to the base at deflector shipping and deflector inclined-use angles, the module and deflector having opposed edges defining a gap therebetween. The invention permits transport of the PV assemblies in a relatively compact form, thus lowering shipping costs, while facilitating installation of the PV assemblies with the PV module at the proper inclination.

Photovoltaic Module Reliability Workshop 2012: February 28 - March 1, 2012

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, S.

2013-11-01

NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

Feasibility Study of Economics and Performance of Solar Photovoltaics at Massachusetts Military Reservation. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stafford, B.; Robichaud, R.; Mosey, G.

2011-07-01

This report presents the results of an assessment of the technical and economic feasibility of deploying photovoltaics (PV) systems on a superfund site located within the Massachusetts Military Reservation (MMR). The site was assessed for possible PV installations. The cost, performance, and site impacts of different PV options were estimated. The economics of the potential systems were analyzed using an electric rate of $0.17/kWh and incentives offered in the State of Massachusetts, such as the solar renewable energy credits. According to calculations, MMR can place 8 MW of ballast-weighted, ground-mounted PV systems on the crowns of the three landfill capsmore » and the borrow pit with the PV modules tilted at 30 degrees.« less

Revolution…Now The Future Arrives for Five Clean Energy Technologies – 2015 Update

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

In 2013, the U.S. Department of Energy (DOE) released the Revolution Now report, highlighting four transformational technologies: land-based wind power, silicon photovoltaic (PV) solar modules, light-emitting diodes (LEDs), and electric vehicles (EVs). That study and its 2014 update showed how dramatic reductions in cost are driving a surge in consumer, industrial, and commercial adoption for these clean energy technologies—as well as yearly progress. In addition to presenting the continued progress made over the last year in these areas, this year’s update goes further. Two separate sections now cover large, central, utility-scale PV plants and smaller, rooftop, distributed PV systems tomore » highlight how both have achieved significant deployment nationwide, and have done so through different innovations, such as easier access to capital for utility-scale PV and reductions of non-hardware costs and third-party ownership for distributed PV. Along with these core technologies« less

Field Performance of Photovoltaic Systems in the Tucson Desert

NASA Astrophysics Data System (ADS)

Orsburn, Sean; Brooks, Adria; Cormode, Daniel; Greenberg, James; Hardesty, Garrett; Lonij, Vincent; Salhab, Anas; St. Germaine, Tyler; Torres, Gabe; Cronin, Alexander

2011-10-01

At the Tucson Electric Power (TEP) solar test yard, over 20 different grid-connected photovoltaic (PV) systems are being tested. The goal at the TEP solar test yard is to measure and model real-world performance of PV systems and to benchmark new technologies such as holographic concentrators. By studying voltage and current produced by the PV systems as a function of incident irradiance, and module temperature, we can compare our measurements of field-performance (in a harsh desert environment) to manufacturer specifications (determined under laboratory conditions). In order to measure high-voltage and high-current signals, we designed and built reliable, accurate sensors that can handle extreme desert temperatures. We will present several benchmarks of sensors in a controlled environment, including shunt resistors and Hall-effect current sensors, to determine temperature drift and accuracy. Finally we will present preliminary field measurements of PV performance for several different PV technologies.

Photovoltaic Subcontract Program. Annual report, FY 1992

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1993-03-01

This report summarizes the fiscal year (FY) 1992 progress of the subcontracted photovoltaic (PV) research and development (R&D) performed under the Photovoltaic Advanced Research and Development Project at the National Renewable Energy Laboratory (NREL)-formerly the Solar Energy Research Institute (SERI). The mission of the national PV program is to develop PV technology for large-scale generation of economically competitive electric power in the United States. The technical sections of the report cover the main areas of the subcontract program: the Crystalline Materials and Advanced Concepts project, the Polycrystalline Thin Films project, Amorphous Silicon Research project, the Photovoltaic Manufacturing Technology (PVMaT) project,more » PV Module and System Performance and Engineering project, and the PV Analysis and Applications Development project. Technical summaries of each of the subcontracted programs provide a discussion of approaches, major accomplishments in FY 1992, and future research directions.« less

Automatic Fault Recognition of Photovoltaic Modules Based on Statistical Analysis of Uav Thermography

NASA Astrophysics Data System (ADS)

Kim, D.; Youn, J.; Kim, C.

2017-08-01

As a malfunctioning PV (Photovoltaic) cell has a higher temperature than adjacent normal cells, we can detect it easily with a thermal infrared sensor. However, it will be a time-consuming way to inspect large-scale PV power plants by a hand-held thermal infrared sensor. This paper presents an algorithm for automatically detecting defective PV panels using images captured with a thermal imaging camera from an UAV (unmanned aerial vehicle). The proposed algorithm uses statistical analysis of thermal intensity (surface temperature) characteristics of each PV module to verify the mean intensity and standard deviation of each panel as parameters for fault diagnosis. One of the characteristics of thermal infrared imaging is that the larger the distance between sensor and target, the lower the measured temperature of the object. Consequently, a global detection rule using the mean intensity of all panels in the fault detection algorithm is not applicable. Therefore, a local detection rule based on the mean intensity and standard deviation range was developed to detect defective PV modules from individual array automatically. The performance of the proposed algorithm was tested on three sample images; this verified a detection accuracy of defective panels of 97 % or higher. In addition, as the proposed algorithm can adjust the range of threshold values for judging malfunction at the array level, the local detection rule is considered better suited for highly sensitive fault detection compared to a global detection rule.

Graphene-enhanced thermal interface materials for heat removal from photovoltaic solar cells

NASA Astrophysics Data System (ADS)

Saadah, M.; Gamalath, D.; Hernandez, E.; Balandin, A. A.

2016-09-01

The increase in the temperature of photovoltaic (PV) solar cells affects negatively their power conversion efficiency and decreases their lifetime. The negative effects are particularly pronounced in concentrator solar cells. Therefore, it is crucial to limit the PV cell temperature by effectively removing the excess heat. Conventional thermal phase change materials (PCMs) and thermal interface materials (TIMs) do not possess the thermal conductivity values sufficient for thermal management of the next generation of PV cells. In this paper, we report the results of investigation of the increased efficiency of PV cells with the use of graphene-enhanced TIMs. Graphene reveals the highest values of the intrinsic thermal conductivity. It was also shown that the thermal conductivity of composites can be increased via utilization of graphene fillers. We prepared TIMs with up to 6% of graphene designed specifically for PV cell application. The solar cells were tested using the solar simulation module. It was found that the drop in the output voltage of the solar panel under two-sun concentrated illumination can be reduced from 19% to 6% when grapheneenhanced TIMs are used. The proposed method can recover up to 75% of the power loss in solar cells.

Experts Outline Pathway for Generating Up to Ten Terawatts of Power from

Science.gov Websites

of PV while also improving the performance of solar modules A drop in the cost of and time required Terawatts of Power from Sunlight by 2030 April 18, 2017 The annual potential of solar energy far exceeds the solar power in the new Science paper, Terawatt-Scale Photovoltaics: Trajectories and Challenges. Fifty

Timothy Silverman | NREL

Science.gov Websites

physical phenomena, PV package reliability, and outdoor PV performance. At NREL, he performs research in advanced concept PV modules. Dr. Silverman studies the performance and reliability of PV modules, including previously studied the degradation of solder joints in high-concentration PV and the outdoor performance of

Enhanced Contacts for Inverted Metamorphic Multi-Junction Solar Cells Using Carbon Nanotube Metal Matrix Composites

DTIC Science & Technology

2018-01-18

to a variety solar energy markets. For instance, micro-cracks have been shown to cause decreased power output in single- and multi-crystalline Si PV ...fingers in silicon wafer solar cells and PV modules," Solar Energy Materials and Solar Cells, vol. 108, pp. 78-81, 1// 2013. [4] T. H. Reijenga and H...AFRL-RV-PS- AFRL-RV-PS- TR-2017-0125 TR-2017-0125 ENHANCED CONTACTS FOR INVERTED METAMORPHIC MULTI-JUNCTION SOLAR CELLS USING CARBON NANOTUBE METAL

Peter Hacke | NREL

Science.gov Websites

photovoltaic (PV) modules, inspections for root cause of module failures in the field, and accelerated lifetime delamination. His research interests are in modeling of degradation processes of PV modules, module integrated analysis of PV degradation data. He also explores accelerated multi-stress and combined stress testing to

Fault detection and diagnosis of photovoltaic systems

NASA Astrophysics Data System (ADS)

Wu, Xing

The rapid growth of the solar industry over the past several years has expanded the significance of photovoltaic (PV) systems. One of the primary aims of research in building-integrated PV systems is to improve the performance of the system's efficiency, availability, and reliability. Although much work has been done on technological design to increase a photovoltaic module's efficiency, there is little research so far on fault diagnosis for PV systems. Faults in a PV system, if not detected, may not only reduce power generation, but also threaten the availability and reliability, effectively the "security" of the whole system. In this paper, first a circuit-based simulation baseline model of a PV system with maximum power point tracking (MPPT) is developed using MATLAB software. MATLAB is one of the most popular tools for integrating computation, visualization and programming in an easy-to-use modeling environment. Second, data collection of a PV system at variable surface temperatures and insolation levels under normal operation is acquired. The developed simulation model of PV system is then calibrated and improved by comparing modeled I-V and P-V characteristics with measured I--V and P--V characteristics to make sure the simulated curves are close to those measured values from the experiments. Finally, based on the circuit-based simulation model, a PV model of various types of faults will be developed by changing conditions or inputs in the MATLAB model, and the I--V and P--V characteristic curves, and the time-dependent voltage and current characteristics of the fault modalities will be characterized for each type of fault. These will be developed as benchmark I-V or P-V, or prototype transient curves. If a fault occurs in a PV system, polling and comparing actual measured I--V and P--V characteristic curves with both normal operational curves and these baseline fault curves will aid in fault diagnosis.

Examination of an optical transmittance test for photovoltaic encapsulation materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, David C.; Bengoechea, Jaione; Bokria, Jayesh G.

2013-09-24

The optical transmittance of encapsulation materials is a key characteristic for their use in photovoltaic (PV) modules. Changes in transmittance with time in the field affect module performance, which may impact product warranties. Transmittance is important in product development, module manufacturing, and field power production (both immediate and long-term). Therefore, an international standard (IEC 62788-1-4) has recently been proposed by the Encapsulation Task-Group within the Working Group 2 (WG2) of the International Electrotechnical Commission (IEC) Technical Committee 82 (TC82) for the quantification of the optical performance of PV encapsulation materials. Existing standards, such as ASTM E903, are general and moremore » appropriately applied to concentrated solar power than to PV. Starting from the optical transmittance measurement, the solar-weighted transmittance of photon irradiance, yellowness index (which may be used in aging studies to assess durability), and ultraviolet (UV) cut-off wavelength may all be determined using the proposed standard. The details of the proposed test are described. The results of a round-robin experiment (for five materials) conducted at seven laboratories to validate the test procedure using representative materials are also presented. For example, the Encapsulation Group actively explored the measurement requirements (wavelength range and resolution), the requirements for the spectrophotometer (including the integrating sphere and instrument accessories, such as a depolarizer), specimen requirements (choice of glass-superstrate and -substrate), and data analysis (relative to the light that may be used in the PV application). The round-robin experiment identified both intra- and inter-laboratory instrument precision and bias for five encapsulation materials (encompassing a range of transmittance and haze-formation characteristics).« less

Examination of an Optical Transmittance Test for Photovoltaic Encapsulation Materials (Presentation)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, D.; Bengoechea, J.; Bokria, J.

2013-09-01

The optical transmittance of encapsulation materials is a key characteristic for their use in photovoltaic (PV) modules. Changes in transmittance with time in the field affect module performance, which may impact product warranties. Transmittance is important in product development, module manufacturing, and field power production (both immediate and long-term). Therefore, an international standard (IEC 62788-1-4) has recently been proposed by the Encapsulation Task-Group within the Working Group 2 (WG2) of the International Electrotechnical Commission (IEC) Technical Committee 82 (TC82) for the quantification of the optical performance of PV encapsulation materials. Existing standards, such as ASTM E903, are general and moremore » appropriately applied to concentrated solar power than to PV. Starting from the optical transmittance measurement, the solar-weighted transmittance of photon irradiance, yellowness index (which may be used in aging studies to assess durability), and ultraviolet (UV) cut-off wavelength may all be determined using the proposed standard. The details of the proposed test are described. The results of a round-robin experiment (for five materials) conducted at seven laboratories to validate the test procedure using representative materials are also presented. For example, the Encapsulation Group actively explored the measurement requirements (wavelength range and resolution), the requirements for the spectrophotometer (including the integrating sphere and instrument accessories, such as a depolarizer), specimen requirements (choice of glass-superstrate and -substrate), and data analysis (relative to the light that may be used in the PV application). The round-robin experiment identified both intra- and inter-laboratory instrument precision and bias for five encapsulation materials (encompassing a range of transmittance and haze-formation characteristics).« less

Maximum power point tracking for photovoltaic applications by using two-level DC/DC boost converter

NASA Astrophysics Data System (ADS)

Moamaei, Parvin

Recently, photovoltaic (PV) generation is becoming increasingly popular in industrial applications. As a renewable and alternative source of energy they feature superior characteristics such as being clean and silent along with less maintenance problems compared to other sources of the energy. In PV generation, employing a Maximum Power Point Tracking (MPPT) method is essential to obtain the maximum available solar energy. Among several proposed MPPT techniques, the Perturbation and Observation (P&O;) and Model Predictive Control (MPC) methods are adopted in this work. The components of the MPPT control system which are P&O; and MPC algorithms, PV module and high gain DC-DC boost converter are simulated in MATLAB Simulink. They are evaluated theoretically under rapidly and slowly changing of solar irradiation and temperature and their performance is shown by the simulation results, finally a comprehensive comparison is presented.

High Step-Up DC—DC Converter for AC Photovoltaic Module with MPPT Control

NASA Astrophysics Data System (ADS)

Sundar, Govindasamy; Karthick, Narashiman; Rama Reddy, Sasi

2014-08-01

This paper presents the high gain step-up BOOST converter which is essential to step up the low output voltage from PV panel to the high voltage according to the requirement of the application. In this paper a high gain BOOST converter with coupled inductor technique is proposed with the MPPT control. Without extreme duty ratios and the numerous turns-ratios of a coupled inductor this converter achieves a high step-up voltage-conversion ratio and the leakage energy of the coupled inductor is efficiently recycled to the load. MPPT control used to extract the maximum power from PV panel by controlling the Duty ratio of the converter. The PV panel, BOOST converter and the MPPT are modeled using Sim Power System blocks in MATLAB/SIMULINK environment. The prototype model of the proposed converter has been implemented with the maximum measured efficiency is up to 95.4% and full-load efficiency is 93.1%.

Georgetown University Photovoltaic Higher Education National Exemplar Facility (PHENEF)

NASA Technical Reports Server (NTRS)

Marshall, N.

1984-01-01

Several photographs of this facility using photovoltaic (PV) cells are shown. An outline is given of the systems requirements, system design and wiring topology, a simplified block design, module electrical characteristics, PV module and PV module matching.

77 FR 63791 - Crystalline Silicon Photovoltaic Cells, Whether or Not Assembled into Modules, from the People's...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-17

...., Jiangsu Sunlink PV Technology Co., Ltd., and JA Solar Technology Yangzhou Co., Ltd. On June 25, 2012, Wuxi... (Chengdu) PV Tianwei New Energy 25.96 Module Co., Ltd. (Chengdu) PV Module Co., Ltd. Canadian Solar.... Chint Solar (Zhejiang) Co., Ltd Chint Solar (Zhejiang) 25.96 Co., Ltd. Suzhou Shenglong PV-Tech Co...

McClellan PV system installation provides key lessons

NASA Astrophysics Data System (ADS)

Kauffman, W. R.

Design features and lessons learned in the installation of a 40 kWp solar cell array to supply power to a market on an airbase are outlined. The fixed-position modules interface with an inverter, ac and dc switchgear, controls, instrumentation, and an energy management system. The power control unit has a peak power tracking feature to maximize output from the 1142 cell modules. The inverter has functioned at over 98 percent efficiency near the 25 kW design range of the array. Moisture sealing to prevent ground faults was found necessary during the installation of the underground cabling.

Photovoltaic module with removable wind deflector

DOEpatents

Botkin, Jonathan [El Cerrito, CA; Graves, Simon [Berkeley, CA; Danning, Matt [Oakland, CA; Culligan, Matthew [Berkeley, CA

2012-08-07

A photovoltaic (PV) module assembly including a PV module, a deflector, and a clip. The PV module includes a PV device and a frame. A PV laminate is assembled to the frame, and the frame includes a support arm forming a seat. The deflector defines a front face and a rear face, with the clip extending from either the trailing frame member or the rear face of the deflector. In a mounted state, the deflector is nested within the seat and is releasably mounted to the trailing frame member via the clip. In some embodiments, the support arm forms a second seat, with the PV module assembly providing a second mounted state in which the deflector is in a differing orientation/slope, nested within the second seat and releasably mounted to the trailing frame member via the clip.

Photovoltaic module with removable wind deflector

DOEpatents

Botkin, Jonathan; Graves, Simon; Danning, Matt; Culligan, Matthew

2014-02-18

A photovoltaic (PV) module assembly including a PV module, a deflector, and a clip. The PV module includes a PV device and a frame. A PV laminate is assembled to the frame, and the frame includes a support arm forming a seat. The deflector defines a front face and a rear face, with the clip extending from either the trailing frame member or the rear face of the deflector. In a mounted state, the deflector is nested within the seat and is releasably mounted to the trailing frame member via the clip. In some embodiments, the support arm forms a second seat, with the PV module assembly providing a second mounted state in which the deflector is in a differing orientation/slope, nested within the second seat and releasably mounted to the trailing frame member via the clip.

Photovoltaic module with removable wind deflector

DOEpatents

Botkin, Jonathan; Graves, Simon; Danning, Matt; Culligan, Matthew

2013-05-28

A photovoltaic (PV) module assembly including a PV module, a deflector, and a clip. The PV module includes a PV device and a frame. A PV laminate is assembled to the frame, and the frame includes a support arm forming a seat. The deflector defines a front face and a rear face, with the clip extending from either the trailing frame member or the rear face of the deflector. In a mounted state, the deflector is nested within the seat and is releasably mounted to the trailing frame member via the clip. In some embodiments, the support arm forms a second seat, with the PV module assembly providing a second mounted state in which the deflector is in a differing orientation/slope, nested within the second seat and releasably mounted to the trailing frame member via the clip.

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

NASA Astrophysics Data System (ADS)

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.

Passive thermal regulation of flat PV modules by coupling the mechanisms of evaporative and fin cooling

NASA Astrophysics Data System (ADS)

Chandrasekar, M.; Senthilkumar, T.

2016-07-01

A passive thermal regulation technique with fins in conjunction with cotton wicks is developed in the present work for controlling the temperature of PV module during its operation. Experiments were conducted with the developed technique in the location of Tiruchirappalli (78.6°E and 10.8°N), Tamil Nadu, India with flat 25 Wp PV module and its viability was confirmed. The PV module temperature got reduced by 12 % while the electrical yield is increased by 14 % with the help of the developed cooling system. Basic energy balance equation applicable for PV module was used to evaluate the module temperatures and a fair agreement was obtained between the theoretical and experimental values for the cases of with cooling and without cooling.

Model Development of Degradation of PV Modules Backsheet with Locating Place of Module

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kempe, Michael D; Wang, Yu; Fairbrother, Andrew

Performance of a photovoltaic (PV) module is related to the micro-environment around the module. The position of photovoltaic modules in an array row have a large effect on the yellowing and gloss of PV module backsheet exposed in Dfa climatic zone (Gaithersburg, MD) with a polyethylene naphthalate (PEN) outer layer. Stress/Response models of yellowing and gloss-losing as function of location parameters of module, including the shed, row, measurement position in a same module and the distance of module location to the row center, are under development. The module installation height had the greatest influence on degradation of PEN PV backsheetmore » in the Dfa climatic zone. The module backsheets at the end of an array have higher degradation rate (edge effect). The edge effect decreases with increasing of module installation heights.« less

Electrical power system WP-04

NASA Astrophysics Data System (ADS)

Nored, Donald L.

Viewgraphs on Space Station Freedom Electrical Power System (EPS) WP-40 are presented. Topics covered include: key EPS technical requirements; photovoltaic power module systems; solar array assembly; blanket containment box and box positioning subassemblies; solar cell; bypass diode assembly; Kapton with atomic oxygen resistant coating; sequential shunt unit; gimbal assembly; energy storage subsystem; thermal control subsystem; direct current switching unit; integrated equipment assembly; PV cargo element; PMAD system; and PMC and AC architecture.

Electrical power system WP-04

NASA Technical Reports Server (NTRS)

Nored, Donald L.

1990-01-01

Viewgraphs on Space Station Freedom Electrical Power System (EPS) WP-40 are presented. Topics covered include: key EPS technical requirements; photovoltaic power module systems; solar array assembly; blanket containment box and box positioning subassemblies; solar cell; bypass diode assembly; Kapton with atomic oxygen resistant coating; sequential shunt unit; gimbal assembly; energy storage subsystem; thermal control subsystem; direct current switching unit; integrated equipment assembly; PV cargo element; PMAD system; and PMC and AC architecture.

On the relationship factor between the PV module temperature and the solar radiation on it for various BIPV configurations

NASA Astrophysics Data System (ADS)

Kaplanis, S.; Kaplani, E.

2014-10-01

Temperatures of c-Si, pc-Si and a-Si PV modules making part of a roof in a building or hanging outside windows with various inclinations were measured with respect to the Intensity of the solar radiation on them under various environmental conditions. A relationship coefficient f was provided whose values are compared to those from a PV array operating in a free standing mode on a terrace. A theoretical model to predict f was elaborated. According to the analysis, the coefficient f takes higher values for PV modules embedded on a roof compared to the free standing PV array. The wind effect is much stronger for the free standing PV than for any BIPV configuration, either the PV is part of the roof, or placed upon the roof, or is placed outside a window like a shadow hanger. The f coefficient depends on various parameters such as angle of inclination, wind speed and direction, as well as solar radiation. For very low wind speeds the effect of the angle of inclination, β, of the PV module with respect to the horizontal on PV temperature is clear. As the wind speed increases, the heat transfer from the PV module shifts from natural flow to forced flow and this effect vanishes. The coefficient f values range from almost 0.01 m2°C/W for free standing PV arrays at strong wind speeds, vW>7m/s, up to around 0.05 m2°C/W for the case of flexible PV modules which make part of the roof in a BIPV system.

Numerical method for angle-of-incidence correction factors for diffuse radiation incident photovoltaic modules

DOE PAGES

Marion, Bill

2017-03-27

Here, a numerical method is provided for solving the integral equation for the angle-of-incidence (AOI) correction factor for diffuse radiation incident photovoltaic (PV) modules. The types of diffuse radiation considered include sky, circumsolar, horizon, and ground-reflected. The method permits PV module AOI characteristics to be addressed when calculating AOI losses associated with diffuse radiation. Pseudo code is provided to aid users in the implementation, and results are shown for PV modules with tilt angles from 0° to 90°. Diffuse AOI losses are greatest for small PV module tilt angles. Including AOI losses associated with the diffuse irradiance will improve predictionsmore » of PV system performance.« less

Photovoltaic balance-of-system designs and costs at PVUSA

NASA Astrophysics Data System (ADS)

Reyes, A. B.; Jennings, C.

1995-05-01

This report is one in a series of 1994-1995 PVUSA reports that document PVUSA lessons learned at demonstration sites in California and Texas. During the last 7 years (1988 to 1994), 16 PV systems ranging from 20 kW to 500 kW have been installed. Six 20-kW emerging module technology (EMT) arrays and three turnkey (i.e., vendor designed and integrated) utility-scale systems were procured and installed at PVUSA's main test site in Davis, California. PVUSA host utilities have installed a total of seven EMT arrays and utility-scale systems in their service areas. Additional systems at Davis and host utility sites are planned. One of PVUSA's key objectives is to evaluate the performance, reliability, and cost of PV balance-of-system (BOS). In the procurement stage PVUSA encouraged innovative design to improve upon present practice by reducing maintenance, improving reliability, or lowering manufacturing or construction costs. The project team worked closely with suppliers during the design stage not only to ensure designs met functional and safety specifications, but to provide suggestions for improvement. This report, intended for the photovoltaic (PV) industry and for utility project managers and engineers considering PV plant construction and ownership, documents PVUSA utility-scale system design and cost lessons learned. Complementary PVUSA topical reports document: construction and safety experience; five-year assessment of EMTs; validation of the Kerman 500-kW grid-support PV plant benefits; PVUSA instrumentation and data analysis techniques; procurement, acceptance, and rating practices for PV power plants; experience with power conditioning units and power quality.

The possibility of developing hybrid PV/T solar system

NASA Astrophysics Data System (ADS)

Dobrnjac, M.; Zivkovic, P.; Babic, V.

2017-05-01

An alternative and cost-effective solution to developing integrated PV system is to use hybrid photovoltaic/thermal (PV/T) solar system. The temperature of PV modules increases due to the absorbed solar radiation that is not converted into electricity, causing a decrease in their efficiency. In hybrid PV/T solar systems the reduction of PV module temperature can be combined with a useful fluid heating. In this paper we present the possibility of developing a new hybrid PV/T solar system. Hybrid PV/T system can provide electrical and thermal energy, thus achieving a higher energy conversion rate of the absorbed solar radiation. We developed PV/T prototype consisted of commercial PV module and thermal panel with our original solution of aluminium absorber with special geometric shapes. The main advantages of our combined PV/T system are: removing of heat from the PV panel; extending the lifetime of photovoltaic cells; excess of the removing heat from PV part is used to heat the fluid in the thermal part of the panel; the possibility of using on the roof and facade constructions because less weight.

Hybrid photovoltaic and thermoelectric module for high concentration solar system

NASA Astrophysics Data System (ADS)

Tamaki, Ryo; Toyoda, Takeshi; Tamura, Yoichi; Matoba, Akinari; Minamikawa, Toshiharu; Tokuda, Masayuki; Masui, Megumi; Okada, Yoshitaka

2017-09-01

A photovoltaic (PV) and thermoelectric (TE) hybrid module was developed for application to high concentration solar systems. The waste heat from the solar cells under concentrated light illumination was utilized to generate additional electricity by assembling TE devices below the multi-junction solar cells (MJSCs). Considering the high operating temperature of the PV and TE hybrid module compared with conventional concentrator PV modules, the TE device could compensate a part of the MJSC efficiency degradation at high temperature. The performance investigation clarified the feasibility of the hybrid PV and TE module under highly concentrated sunlight illumination.

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

NASA Astrophysics Data System (ADS)

Hanak, J. J.; Kaschmitter, J. L.

1991-05-01

An ultralight, flexible photovoltaic (PV) array of amorphous silicon (a-Si) has been identified as a potential low-cost power source for small satellites. We have conducted a survey 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 BOL performance at 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 EOL power output after 10 years in a nominal low-earth orbit would be 80 percent of BOL, the degradation being due to largely light-induced effects (minus 10 to minus 15 percent) and in part (minus 5 percent) 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 US 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. One new US developer has emerged as a future potential supplier of a-Si PV devices on thin, polyimide substrates.

Design and development of high performance solar photovoltaic inverter with advanced modulation techniques to improve power quality

NASA Astrophysics Data System (ADS)

Alexander Stonier, Albert

2017-02-01

In addition to the focus towards growing demand on electrical energy due to the increase in population, industries, consumer loads, etc., the need for improving the quality of electrical power also needs to be considered. The design and development of solar photovoltaic (PV) inverter with reduced harmonic distortions is proposed. Unlike the conventional solar PV inverters, the proposed inverter provides the advantages of reduced harmonic distortions thereby intend towards the improvement in power quality. This inverter comprises of multiple stages which provides the required 230VRMS, 50 Hz in spite of variations in solar PV due to temperature and irradiance. The reduction of harmonics is governed by applying proper switching sequences required for the inverter switches. The detailed analysis is carried out by employing different switching techniques and observing its performance. With a separate mathematical model for a solar PV, simulations are performed in MATLAB software. To show the advantage of the system proposed, a 3 kWp photovoltaic plant coupled with multilevel inverter is demonstrated in hardware. The novelty resides in the design of a single chip controller which can provide the switching sequence based on the requirement and application. As per the results obtained, the solar-fed multistage inverter improves the quality of power which makes this inverter suitable for both stand-alone and grid-connected systems.

NREL Adds Solar Array Field to Help Inform Consumers | NREL

Science.gov Websites

PV modules at NREL's new solar array field. Workers install PV modules just north of the NREL parking be Added Each Year Once completed, the new solar array field will house four rows of PV modules. The the lifetime of a PV system, and that increases the per-kilowatt-hour cost of generating solar

Stabilized PV system

DOEpatents

Dinwoodie, Thomas L.

2002-12-17

A stabilized PV system comprises an array of photovoltaic (PV) assemblies mounted to a support surface. Each PV assembly comprises a PV module and a support assembly securing the PV module to a position overlying the support surface. The array of modules is circumscribed by a continuous, belt-like perimeter assembly. Cross strapping, extending above, below or through the array, or some combination of above, below and through the array, secures a first position along the perimeter assembly to at least a second position along the perimeter assembly thereby stabilizing the array against wind uplift forces. The first and second positions may be on opposite sides on the array.

Energy storage and thermal control system design status. [for space station power supplies

NASA Technical Reports Server (NTRS)

Simons, Stephen N.; Willhoite, Bryan C.; Van Ommering, Gert

1989-01-01

The Space Station Freedom electric power system (EPS) will initially rely on photovoltaics for power generation and Ni/H2 batteries for electrical energy storage. The current design for the development status of two major subsystems in the PV Power Module is discussed. The energy storage subsystem comprised of high capacity Ni/H2 batteries and the single-phase thermal control system that rejects the excess heat generated by the batteries and other components associated with power generation andstorage is described.

Analyzing the Energy Performance, Wind Loading, and Costs of Photovoltaic Slat Modules on Commercial Rooftops

DOE Office of Scientific and Technical Information (OSTI.GOV)

Van Geet, Otto D.; Fu, Ran; Horowitz, Kelsey A.

NREL studied a new type of photovoltaic (PV) module configuration wherein multiple narrow, tilted slats are mounted in a single frame. Each slat of the PV slat module contains a single row of cells and is made using ordinary crystalline silicon PV module materials and processes, including a glass front sheet and weatherproof polymer encapsulation. Compared to a conventional ballasted system, a system using slat modules offer higher energy production and lower weight at lower LCOE. The key benefits of slat modules are reduced wind loading, improved capacity factor and reduced installation cost. First, the individual slats allow air tomore » flow through, which reduce wind loading. Using PV performance modeling software, we compared the performance of an optimized installation of slats modules to a typical installation of conventional modules in a ballasted rack mounting system. Based on the results of the performance modeling two different row tilt and spacing were tested in a wind tunnel. Scaled models of the PV Slat modules were wind tunnel tested to quantify the wind loading of a slat module system on a commercial rooftop, comparing the results to conventional ballasted rack mounted PV modules. Some commercial roofs do not have sufficient reserve dead load capacity to accommodate a ballasted system. A reduced ballast system design could make PV system installation on these roofs feasible for the first time without accepting the disadvantages of penetrating mounts. Finally, technoeconomic analysis was conducted to enable an economic comparison between a conventional commercial rooftop system and a reduced-ballast slat module installation.« less

Modeling of a VMJ PV array under Gaussian high intensity laser power beam condition

NASA Astrophysics Data System (ADS)

Eom, Jeongsook; Kim, Gunzung; Park, Yongwan

2018-02-01

The high intensity laser power beaming (HILPB) system is one of the most promising systems in the long-rang wireless power transfer field. The vertical multi-junction photovoltaic (VMJ PV) array converts the HILPB into electricity to power the load or charges a battery. The output power of a VMJ PV array depends mainly on irradiance values of each VMJ PV cells. For simulating an entire VMJ PV array, the irradiance profile of the Gaussian HILPB and the irradiance level of the VMJ PV cell are mathematically modeled first. The VMJ PV array is modeled as a network with dimension m*n, where m represents the number of VMJ PV cells in a column, and n represents the number of VMJ PV cells in a row. In order to validate the results obtained in modeling and simulation, a laboratory setup was developed using 55 VMJ PV array. By using the output power model of VMJ PV array, we can establish an optimal power transmission path by the receiver based on the received signal strength. When the laser beam from multiple transmitters aimed at a VMJ PV array at the same time, the received power is the sum of all energy at a VMJ PV array. The transmitter sends its power characteristics as optically coded laser pulses and powers as HILPB. Using the attenuated power model and output power model of VMJ PV array, the receiver can estimate the maximum receivable powers from the transmitters and select optimal transmitters.

Design and long-term monitoring of DSC/CIGS tandem solar module

NASA Astrophysics Data System (ADS)

Vildanova, M. F.; Nikolskaia, A. B.; Kozlov, S. S.; Shevaleevskiy, O. I.

2015-11-01

This paper describes the design and development of tandem dye-sensitized/Cu(In, Ga)Se (DSC/CIGS) PV modules. The tandem PV module comprised of the top DSC module and a bottom commercial 0,8 m2 CIGS module. The top DSC module was made of 10 DSC mini-modules with the field size of 20 × 20 cm2 each. Tandem DSC/CIGS PV modules were used for providing the long-term monitoring of energy yield and electrical parameters in comparison with standalone CIGS modules under outdoor conditions. The outdoor test facility, containing solar modules of both types and a measurement unit, was located on the roof of the Institute of Biochemical Physics in Moscow. The data obtained during monitoring within the 2014 year period has shown the advantages of the designed tandem DSC/CIGS PV-modules over the conventional CIGS modules, especially for cloudy weather and low-intensity irradiation conditions.

User's Manual for Data for Validating Models for PV Module Performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marion, W.; Anderberg, A.; Deline, C.

2014-04-01

This user's manual describes performance data measured for flat-plate photovoltaic (PV) modules installed in Cocoa, Florida, Eugene, Oregon, and Golden, Colorado. The data include PV module current-voltage curves and associated meteorological data for approximately one-year periods. These publicly available data are intended to facilitate the validation of existing models for predicting the performance of PV modules, and for the development of new and improved models. For comparing different modeling approaches, using these public data will provide transparency and more meaningful comparisons of the relative benefits.

2008 Solar Technologies Market Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Price, S.; Margolis, R.; Barbose, G.

2010-01-01

The focus of this report is the U.S. solar electricity market, including photovoltaic (PV) and concentrating solar power (CSP) technologies. The report is organized into five chapters. Chapter 1 provides an overview of global and U.S. installation trends. Chapter 2 presents production and shipment data, material and supply chain issues, and solar industry employment trends. Chapter 3 presents cost, price, and performance trends. Chapter 4 discusses policy and market drivers such as recently passed federal legislation, state and local policies, and developments in project financing. Chapter 5 provides data on private investment trends and near-term market forecasts. Highlights of thismore » report include: (1) The global PV industry has seen impressive growth rates in cell/module production during the past decade, with a 10-year compound annual growth rate (CAGR) of 46% and a 5-year CAGR of 56% through 2008. (2) Thin-film PV technologies have grown faster than crystalline silicon over the past 5 years, with a 10-year CAGR of 47% and a 5-year CAGR of 87% for thin-film shipments through 2008. (3) Global installed PV capacity increased by 6.0 GW in 2008, a 152% increase over 2.4 GW installed in 2007. (4) The United States installed 0.34 GW of PV capacity in 2008, a 63% increase over 0.21 GW in 2007. (5) Global average PV module prices dropped 23% from $4.75/W in 1998 to $3.65/W in 2008. (6) Federal legislation, including the Emergency Economic Stabilization Act of 2008 (EESA, October 2008) and the American Recovery and Reinvestment Act (ARRA, February 2009), is providing unprecedented levels of support for the U.S. solar industry. (7) In 2008, global private-sector investment in solar energy technology topped $16 billion, including almost $4 billion invested in the United States. (8) Solar PV market forecasts made in early 2009 anticipate global PV production and demand to increase fourfold between 2008 and 2012, reaching roughly 20 GW of production and demand by 2012. (9) Globally, about 13 GW of CSP was announced or proposed through 2015, based on forecasts made in mid-2009. Regional market shares for the 13 GW are about 51% in the United States, 33% in Spain, 8% in the Middle East and North Africa, and 8% in Australasia, Europe, and South Africa. Of the 6.5-GW project pipeline in the United States, 4.3 GW have power purchase agreements (PPAs). The PPAs comprise 41% parabolic trough, 40% power tower, and 19% dish-engine systems.« less

Outdoor Performance of a Thin-Film Gallium-Arsenide Photovoltaic Module

DOE Office of Scientific and Technical Information (OSTI.GOV)

Silverman, T. J.; Deceglie, M. G.; Marion, B.

2013-06-01

We deployed a 855 cm2 thin-film, single-junction gallium arsenide (GaAs) photovoltaic (PV) module outdoors. Due to its fundamentally different cell technology compared to silicon (Si), the module responds differently to outdoor conditions. On average during the test, the GaAs module produced more power when its temperature was higher. We show that its maximum-power temperature coefficient, while actually negative, is several times smaller in magnitude than that of a Si module used for comparison. The positive correlation of power with temperature in GaAs is due to temperature-correlated changes in the incident spectrum. We show that a simple correction based on precipitablemore » water vapor (PWV) brings the photocurrent temperature coefficient into agreement with that measured by other methods and predicted by theory. The low operating temperature and small temperature coefficient of GaAs give it an energy production advantage in warm weather.« less

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

NASA Technical Reports Server (NTRS)

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.

Bracket for photovoltaic modules

DOEpatents

Ciasulli, John; Jones, Jason

2014-06-24

Brackets for photovoltaic ("PV") modules are described. In one embodiment, a saddle bracket has a mounting surface to support one or more PV modules over a tube, a gusset coupled to the mounting surface, and a mounting feature coupled to the gusset to couple to the tube. The gusset can have a first leg and a second leg extending at an angle relative to the mounting surface. Saddle brackets can be coupled to a torque tube at predetermined locations. PV modules can be coupled to the saddle brackets. The mounting feature can be coupled to the first gusset and configured to stand the one or more PV modules off the tube.

Method of manufacturing a large-area segmented photovoltaic module

DOEpatents

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.

DC-based smart PV-powered home energy management system based on voltage matching and RF module

PubMed Central

Hasan, W. Z. W.

2017-01-01

The main tool for measuring system efficiency in homes and offices is the energy monitoring of the household appliances’ consumption. With the help of GUI through a PC or smart phone, there are various applications that can be developed for energy saving. This work describes the design and prototype implementation of a wireless PV-powered home energy management system under a DC-distribution environment, which allows remote monitoring of appliances’ energy consumptions and power rate quality. The system can be managed by a central computer, which obtains the energy data based on XBee RF modules that access the sensor measurements of system components. The proposed integrated prototype framework is characterized by low power consumption due to the lack of components and consists of three layers: XBee-based circuit for processing and communication architecture, solar charge controller, and solar-battery-load matching layers. Six precise analogue channels for data monitoring are considered to cover the energy measurements. Voltage, current and temperature analogue signals were accessed directly from the remote XBee node to be sent in real time with a sampling frequency of 11–123 Hz to capture the possible surge power. The performance shows that the developed prototype proves the DC voltage matching concept and is able to provide accurate and precise results. PMID:28934271

DC-based smart PV-powered home energy management system based on voltage matching and RF module.

PubMed

Sabry, Ahmad H; Hasan, W Z W; Ab Kadir, Mza; Radzi, M A M; Shafie, S

2017-01-01

The main tool for measuring system efficiency in homes and offices is the energy monitoring of the household appliances' consumption. With the help of GUI through a PC or smart phone, there are various applications that can be developed for energy saving. This work describes the design and prototype implementation of a wireless PV-powered home energy management system under a DC-distribution environment, which allows remote monitoring of appliances' energy consumptions and power rate quality. The system can be managed by a central computer, which obtains the energy data based on XBee RF modules that access the sensor measurements of system components. The proposed integrated prototype framework is characterized by low power consumption due to the lack of components and consists of three layers: XBee-based circuit for processing and communication architecture, solar charge controller, and solar-battery-load matching layers. Six precise analogue channels for data monitoring are considered to cover the energy measurements. Voltage, current and temperature analogue signals were accessed directly from the remote XBee node to be sent in real time with a sampling frequency of 11-123 Hz to capture the possible surge power. The performance shows that the developed prototype proves the DC voltage matching concept and is able to provide accurate and precise results.

Considerations for a Standardized Test for Potential-Induced Degradation of Crystalline Silicon PV Modules (Presentation)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hacke, P.

2012-03-01

Over the past decade, there have been observations of module degradation and power loss because of the stress that system voltage bias exerts. This results in part from qualification tests and standards note adequately evaluating for the durability of modules to the long-term effects of high voltage bias that they experience in fielded arrays. This talk deals with factors for consideration, progress, and information still needed for a standardized test for degradation due to system voltage stress.

Dirk Jordan | NREL

Science.gov Websites

quantify module degradation rates. Statistical analysis of reported degradation rates of PV modules degradation rates," Prog. in PV 24(7), 2016, DOI: 10.1002/pip.2744 Jordan D.C., Silverman T.J PV, 2017, DOI: 10.1002/pip.2866 Jordan D.C., Silverman T.J., Sekulic B., Kurtz S.R., "PV

Photovoltaic performance and reliability workshop

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kroposki, B

1996-10-01

This proceedings is the compilation of papers presented at the ninth PV Performance and Reliability Workshop held at the Sheraton Denver West Hotel on September 4--6, 1996. This years workshop included presentations from 25 speakers and had over 100 attendees. All of the presentations that were given are included in this proceedings. Topics of the papers included: defining service lifetime and developing models for PV module lifetime; examining and determining failure and degradation mechanisms in PV modules; combining IEEE/IEC/UL testing procedures; AC module performance and reliability testing; inverter reliability/qualification testing; standardization of utility interconnect requirements for PV systems; need activitiesmore » to separate variables by testing individual components of PV systems (e.g. cells, modules, batteries, inverters,charge controllers) for individual reliability and then test them in actual system configurations; more results reported from field experience on modules, inverters, batteries, and charge controllers from field deployed PV systems; and system certification and standardized testing for stand-alone and grid-tied systems.« less

Parallel-Connected Photovoltaic Inverters: Zero Frequency Sequence Harmonic Analysis and Solution

NASA Astrophysics Data System (ADS)

Carmeli, Maria Stefania; Mauri, Marco; Frosio, Luisa; Bezzolato, Alberto; Marchegiani, Gabriele

2013-05-01

High-power photovoltaic (PV) plants are usually constituted of the connection of different PV subfields, each of them with its interface transformer. Different solutions have been studied to improve the efficiency of the whole generation system. In particular, transformerless configurations are the more attractive one from efficiency and costs point of view. This paper focuses on transformerless PV configurations characterised by the parallel connection of interface inverters. The problem of zero sequence current due to both the parallel connection and the presence of undesirable parasitic earth capacitances is considered and a solution, which consists of the synchronisation of pulse-width modulation triangular carrier, is proposed and theoretically analysed. The theoretical analysis has been validated through simulation and experimental results.

Photovoltaic array mounting apparatus, systems, and methods

DOEpatents

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.

Energy storage and thermal control system design status

NASA Technical Reports Server (NTRS)

Simons, Stephen N.; Willhoite, Bryan C.; Vanommering, Gert

1989-01-01

The Space Station Freedom electric power system (EPS) will initially rely on photovoltaics for power generation and Ni/H2 batteries for electrical energy storage. The current design for and the development status of two major subsystems in the PV Power Module is discussed. The energy storage subsystem comprised of high capacity Ni/H2 batteries and the single-phase thermal control system that rejects the excess heat generated by the batteries and other components associated with power generation and storage is described.

Measurement system for determination of current-voltage characteristics of PV modules

NASA Astrophysics Data System (ADS)

Idzkowski, Adam; Walendziuk, Wojciech; Borawski, Mateusz; Sawicki, Aleksander

2015-09-01

The realization of a laboratory stand for testing photovoltaic panels is presented here. The project of the laboratory stand was designed in SolidWorks software. The aim of the project was to control the electrical parameters of a PV panel. For this purpose a meter that measures electrical parameters i.e. voltage, current and power, was realized. The meter was created with the use of LabJack DAQ device and LabVIEW software. The presented results of measurements were obtained in different conditions (variable distance from the source of light, variable tilt angle of the panel). Current voltage characteristics of photovoltaic panel were created and all parameters could be detected in different conditions. The standard uncertainties of sample voltage, current, power measurements were calculated. The paper also gives basic information about power characteristics and efficiency of a solar cell.

International PV QA Task Force's Proposed Comparative Rating System for PV Modules: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wohlgemuth, J.; Kurtz, S.

The International PV Quality Assurance Task Force is developing a rating system that provides comparative information about the relative durability of PV modules. Development of accelerated stress tests that can provide such comparative information is seen as a major step toward being able to predict PV module service life. This paper will provide details of the ongoing effort to determine the format of such an overall module rating system. The latest proposal is based on using three distinct climate zones as defined in IEC 60721-2-1 for two different mounting systems. Specific stresses beyond those used in the qualification tests aremore » being developed for each of the selected climate zones.« less

Concentrator photovoltaic module architectures with capabilities for capture and conversion of full global solar radiation

DOE PAGES

Lee, Kyu-Tae; Yao, Yuan; He, Junwen; ...

2016-12-05

Emerging classes ofconcentrator photovoltaic (CPV) modules reach efficiencies that are far greater than those of even the highest performance flat-plate PV technologies, with architectures that have the potential to provide the lowest cost of energy in locations with high direct normal irradiance (DNI). A disadvantage is their inability to effectively use diffuse sunlight, thereby constraining widespread geographic deployment and limiting performance even under the most favorable DNI conditions. This study introduces a module design that integrates capabilities in flat-plate PV directly with the most sophisticated CPV technologies, for capture of both direct and diffuse sunlight, thereby achieving efficiency in PVmore » conversion of the global solar radiation. Specific examples of this scheme exploit commodity silicon (Si) cells integrated with two different CPV module designs, where they capture light that is not efficiently directed by the concentrator optics onto large-scale arrays of miniature multijunction (MJ) solar cells that use advanced III-V semiconductor technologies. In this CPV + scheme ("+" denotes the addition of diffuse collector), the Si and MJ cells operate independently on indirect and direct solar radiation, respectively. On-sun experimental studies of CPV + modules at latitudes of 35.9886° N (Durham, NC), 40.1125° N (Bondville, IL), and 38.9072° N (Washington, DC) show improvements in absolute module efficiencies of between 1.02% and 8.45% over values obtained using otherwise similar CPV modules, depending on weather conditions. These concepts have the potential to expand the geographic reach and improve the cost-effectiveness of the highest efficiency forms of PV power generation.« less

Model Predictive Control techniques with application to photovoltaic, DC Microgrid, and a multi-sourced hybrid energy system

NASA Astrophysics Data System (ADS)

Shadmand, Mohammad Bagher

Renewable energy sources continue to gain popularity. However, two major limitations exist that prevent widespread adoption: availability and variability of the electricity generated and the cost of the equipment. The focus of this dissertation is Model Predictive Control (MPC) for optimal sized photovoltaic (PV), DC Microgrid, and multi-sourced hybrid energy systems. The main considered applications are: maximum power point tracking (MPPT) by MPC, droop predictive control of DC microgrid, MPC of grid-interaction inverter, MPC of a capacitor-less VAR compensator based on matrix converter (MC). This dissertation firstly investigates a multi-objective optimization technique for a hybrid distribution system. The variability of a high-penetration PV scenario is also studied when incorporated into the microgrid concept. Emerging (PV) technologies have enabled the creation of contoured and conformal PV surfaces; the effect of using non-planar PV modules on variability is also analyzed. The proposed predictive control to achieve maximum power point for isolated and grid-tied PV systems speeds up the control loop since it predicts error before the switching signal is applied to the converter. The low conversion efficiency of PV cells means we want to ensure always operating at maximum possible power point to make the system economical. Thus the proposed MPPT technique can capture more energy compared to the conventional MPPT techniques from same amount of installed solar panel. Because of the MPPT requirement, the output voltage of the converter may vary. Therefore a droop control is needed to feed multiple arrays of photovoltaic systems to a DC bus in microgrid community. Development of a droop control technique by means of predictive control is another application of this dissertation. Reactive power, denoted as Volt Ampere Reactive (VAR), has several undesirable consequences on AC power system network such as reduction in power transfer capability and increase in transmission loss if not controlled appropriately. Inductive loads which operate with lagging power factor consume VARs, thus load compensation techniques by capacitor bank employment locally supply VARs needed by the load. Capacitors are highly unreliable components due to their failure modes and aging inherent. Approximately 60% of power electronic devices failure such as voltage-source inverter based static synchronous compensator (STATCOM) is due to the use of aluminum electrolytic DC capacitors. Therefore, a capacitor-less VAR compensation is desired. This dissertation also investigates a STATCOM capacitor-less reactive power compensation that uses only inductors combined with predictive controlled matrix converter.

PVMaT 1998 overview

NASA Astrophysics Data System (ADS)

Mittchell, Richard L.; Symko-Davies, Martha; Thomas, Holly P.; Witt, C. Edwin

1999-03-01

The Photovoltaic Manufacturing Technology (PVMaT) Project is a government/industry research and development (R&D) partnership between the U.S. federal government (through the U.S. Department of Energy [DOE]) and members of the U.S. PV industry. The goals of PVMaT are to assist the U.S. PV industry improve module manufacturing processes and equipment; accelerate manufacturing cost reductions for PV modules, balance-of-systems components, and integrated systems; increase commercial product performance and reliability; and enhance investment opportunities for substantial scale-ups of U.S.-based PV manufacturing plant capacities. The approach for PVMaT has been to cost-share the R&D risk as industry explores new manufacturing options and ideas for improved PV modules and components, advances system and product integration, and develops new system designs. These activities will lead to overall reduced system life-cycle costs for reliable PV end-products. The 1994 PVMaT Product-Driven BOS and Systems activities, as well as Product-Driven Module Manufacturing R&D activities, are just being completed. Fourteen new subcontracts have just been awarded in the areas of PV System and Component Technology and Module Manufacturing Technology. Government funding, subcontractor cost-sharing, and a comparison of the relative efforts by PV technology throughout the PVMaT project are also discussed.

Moving Toward Quantifying Reliability - The Next Step in a Rapidly Maturing PV Industry: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, Sarah; Sample, Tony; Wohlgemuth, John

2015-12-07

Some may say that PV modules are moving toward being a simple commodity, but most major PV customers ask: 'How can I minimize chances of a module recall?' Or, 'How can I quantify the added value of a 'premium' module?' Or, 'How can I assess the value of an old PV system that I'm thinking of purchasing?' These are all questions that PVQAT (the International PV Quality Assurance Task Force) and partner organizations are working to answer. Defining standard methods for ensuring minimal acceptable quality of PV modules, differentiating modules that provide added value in the toughest of environments, andmore » creating a process (e.g. through IECRE [1]) that can follow a PV system from design through installation and operation are tough tasks, but having standard approaches for these will increase confidence, reduce costs, and be a critical foundation of a mature PV industry. This paper summarizes current needs for new tests, some challenges for defining those tests, and some of the key efforts toward development of international standards, emphasizing that meaningful quantification of reliability (as in defining a service life prediction) must be done in the context of a specific product with design parameters defined through a quality management system.« less

Structural and physical properties of the dust particles in Qatar and their influence on the PV panel performance.

PubMed

Aïssa, Brahim; Isaifan, Rima J; Madhavan, Vinod E; Abdallah, Amir A

2016-08-16

Recently, extensive R&D has been conducted, both by industry and academia, to significantly raise the conversion efficiency of commercial photovoltaic (PV) modules. The installation of PV systems aimed at optimizing solar energy yield is primarily dictated by its geographic location and installation design to maximize solar exposure. However, even when these characteristics have been addressed appropriately, there are other factors that adversely affect the performance of PV systems, namely the temperature-induced voltage decrease leading to a PV power loss, and the dust accumulation (soiling). The latter is the lesser acknowledged factor that significantly influences the performance of PV installations especially in the Middle East region. In this paper we report on the investigation of the structural and physical properties of the desert-dust particles in the State of Qatar. The dust particles were collected directly from the PV panels installed in desert environment and characterized by different techniques, including scanning electron, optical and atomic force microscopies, X-ray diffraction, energy-dispersive, UV-Vis, micro-Raman and Fourier transform infrared spectroscopy. The vibrating sample magnetometry analyses were also conducted to study the magnetic properties of the dust particles. The influence of the dust accumulation on the PV panel performance was also presented and discussed.

Structural and physical properties of the dust particles in Qatar and their influence on the PV panel performance

NASA Astrophysics Data System (ADS)

Aïssa, Brahim; Isaifan, Rima J.; Madhavan, Vinod E.; Abdallah, Amir A.

2016-08-01

Recently, extensive R&D has been conducted, both by industry and academia, to significantly raise the conversion efficiency of commercial photovoltaic (PV) modules. The installation of PV systems aimed at optimizing solar energy yield is primarily dictated by its geographic location and installation design to maximize solar exposure. However, even when these characteristics have been addressed appropriately, there are other factors that adversely affect the performance of PV systems, namely the temperature-induced voltage decrease leading to a PV power loss, and the dust accumulation (soiling). The latter is the lesser acknowledged factor that significantly influences the performance of PV installations especially in the Middle East region. In this paper we report on the investigation of the structural and physical properties of the desert-dust particles in the State of Qatar. The dust particles were collected directly from the PV panels installed in desert environment and characterized by different techniques, including scanning electron, optical and atomic force microscopies, X-ray diffraction, energy-dispersive, UV-Vis, micro-Raman and Fourier transform infrared spectroscopy. The vibrating sample magnetometry analyses were also conducted to study the magnetic properties of the dust particles. The influence of the dust accumulation on the PV panel performance was also presented and discussed.

A technological review on electric vehicle DC charging stations using photovoltaic sources

NASA Astrophysics Data System (ADS)

Youssef, Cheddadi; Fatima, Errahimi; najia, Es-sbai; Chakib, Alaoui

2018-05-01

Within the next few years, Electrified vehicles are destined to become the essential component of the transport field. Consequently, the charging infrastructure should be developed in the same time. Among this substructure, Charging stations photovoltaic-assisted are attracting a substantial interest due to increased environmental awareness, cost reduction and rise in efficiency of the PV modules. The intention of this paper is to review the technological status of Photovoltaic–Electric vehicle (PV-EV) charging stations during the last decade. The PV-EV charging station is divided into two categories, which are PV-grid and PV-standalone charging systems. From a practical point view, the distinction between the two architectures is the bidirectional inverter, which is added to link the station to the smart grid. The technological infrastructure includes the common hardware components of every station, namely: PV array, dc-dc converter provided with MPPT control, energy storage unit, bidirectional dc charger and inverter. We investigate, compare and evaluate many valuable researches that contain the design and control of PV-EV charging system. Additionally, this concise overview reports the studies that include charging standards, the power converters topologies that focus on the adoption of Vehicle-to grid technology and the control for both PV–grid and PV standalone DC charging systems.

Standardization of the energy performance of photovoltaic modules in real operating conditions

NASA Astrophysics Data System (ADS)

Viganó, Davide; Kenny, Robert P.; Müllejans, Harald; Alimonti, Gianluca

2014-12-01

The performance of a PV module at STC [1] is a useful indicator for comparing the peak performance of different module types, but on its own is not sufficient to accurately predict how much energy a module will deliver in the field when subjected to a wide range of real operating conditions [2]. An Energy Rating approach has to be preferred for that aim. It is currently under development the standard series IEC 61853 on Energy Rating, for which only part 1 [3] has been issued. It describes methods to characterize the module performance as a function of irradiance and temperature. The reproducibility of the power matrix measurements obtained by the three different methods specified in the standard, namely: under natural sunlight using a tracking system; under natural sunlight without tracker; and a large area pulsed solar simulator of Class AAA were evaluated and discussed [4,5]. The work here presented is focused on the second method listed above, which explores the real working conditions for a PV device and therefore it represents the situation where Energy Rating procedures are expected to give the largest deviations from the STC predictions. The system for continuous monitoring of module performances, already implemented at ESTI, has been recently replaced with a new system having a number of improvements described in the following. The two system results have been compared showing a discrete compatibility. The two power matrices are then merged together using a weighted average and compared to those acquired with the other two remaining "ideal" systems. An interesting tendency seems to come up from this comparison, making the power rating under real operating conditions an essential procedure for energy rating purposes.

How Can We Make PV Modules Safer?: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wohlgemuth, J. H.; Kurtz, S. R.

2012-06-01

Safety is a prime concern for the photovoltaics (PV) industry. As a technology deployed on residential and commercial buildings, it is critical that PV not cause damage to the buildings nor harm the occupants. Many of the PV systems on buildings are of sufficiently high voltage (300 to 600 Volts dc) that they may present potential hazards. These PV systems must be safe in terms of mechanical damage (nothing falls on someone), shock hazard (no risk of electrical shock when touching an exposed circuit element), and fire (the modules neither cause nor promote a fire). The present safety standards (IECmore » 61730 and UL 1703) do a good job of providing for design rules and test requirements for mechanical, shock, and spread of flame dangers. However, neither standard addresses the issue of electrical arcing within a module that can cause a fire. To make PV modules, they must be designed, built, and installed with an emphasis on minimizing the potential for open circuits and ground faults. This paper provides recommendations on redundant connection designs, robust mounting methods, and changes to the safety standards to yield safer PV modules.« less

Photovoltaic module kit including connector assembly for non-penetrating array installation

DOEpatents

Botkin, Jonathan; Graves, Simon; Danning, Matt; Culligan, Matthew

2013-12-31

A PV module kit for non-penetrating rooftop installation, including a plurality of PV modules and a plurality of connectors. Each of the PV modules includes a PV laminate and a frame forming a mounting region assembled thereto. The connectors include a male connector having a male fastener extending from a head, and a female connector having a female fastener assempbled within a head. The heads are entirely formed of plastic. The kit provides a mounted array state including a junction at which the mounting regions of at least two of the PV modules are aligned and interconnected by engagement of the male connector with the female connector. The so-formed junction is substantially electrically insulated. The plurality of connectors can further include a spacer connector including a head forming a bore sized slidably receive the male fastener, with all of the connector heads being identical.

Photovoltaic system with improved AC connections and method of making same

DOEpatents

Cioffi, Philip Michael; Todorovic, Maja Harfman; Herzog, Michael Scott; Korman, Charles Steven; Doherty, Donald M.; Johnson, Neil Anthony

2018-02-13

An alternating current (AC) harness for a photovoltaic (PV) system includes a wire assembly having a first end and a second end, the wire assembly having a plurality of lead wires, and at least one AC connection module positioned at a location along a length of the wire assembly between the first end and the second end. Further, the at least one AC connection module includes a first connection terminal electrically coupled to the plurality of lead wires of the wire assembly and constructed to electrically couple the wire assembly with an output of a first PV module of the PV system. The at least one AC connection module also includes a second connection terminal electrically coupled to the plurality of lead wires of the wire assembly and constructed to electrically couple the wire assembly with an output of a second PV module of the PV system.

Photovoltaic module kit including connector assembly for non-penetrating array installation

DOEpatents

Botkin, Jonathan [El Cerrito, CA; Graves, Simon [Berkeley, CA; Danning, Matt [Oakland, CA; Culligan, Matthew [Berkeley, CA

2011-11-22

A PV module kit for non-penetrating rooftop installation, including a plurality of PV modules and a plurality of connectors. Each of the PV modules includes a PV laminate and a frame forming a mounting region assembled thereto. The connectors include a male connector having a male fastener extending from a head, and a female connector having a female fastener assembled within a head. The heads are entirely formed of plastic. The kit provides a mounted array state including a junction at which the mounting region of at least two of the PV modules are aligned and interconnected by engagement of the male connector with the female connector. The so-formed junction is substantially electrically insulated. The plurality of connectors can further include a spacer connector including a head forming a bore sized to slidably receive the male fastener, with all of the connector heads being identical.

Photovoltaic module kit including connector assembly for non-penetrating array installation

DOEpatents

Botkin, Jonathan; Graves, Simon; Danning, Matt; Culligan, Matthew

2012-10-23

A PV module kit for non-penetrating rooftop installation, including a plurality of PV modules and a plurality of connectors. Each of the PV modules includes a PV laminate and a frame forming a mounting region assembled thereto. The connectors include a male connector having a male fastener extending from a head, and a female connector having a female fastener assembled within a head. The heads are entirely formed of plastic. The kit provides a mounted array state including a junction at which the mounting region of at least two of the PV modules are aligned and interconnected by engagement of the male connector with the female connector. The so-formed junction is substantially electrically insulated. The plurality of connectors can further include a spacer connector including a head forming a bore sized to slidably receive the male fastener, with all of the connector heads being identical.

Durable crystalline Si photovoltaic modules based on silicone-sheet encapsulants

NASA Astrophysics Data System (ADS)

Hara, Kohjiro; Ohwada, Hiroto; Furihata, Tomoyoshi; Masuda, Atsushi

2018-02-01

Crystalline Si photovoltaic (PV) modules were fabricated with sheets of poly(dimethylsiloxane) (silicone) as an encapsulant. The long-term durability of the silicone-encapsulated PV modules was experimentally investigated. The silicone-based modules enhanced the long-term durability against potential-induced degradation (PID) and a damp-heat (DH) condition at 85 °C with 85% relative humidity (RH). In addition, we designed and fabricated substrate-type Si PV modules based on the silicone encapsulant and an Al-alloy plate as the substratum, which demonstrated high impact resistance and high incombustible performance. The high chemical stability, high volume resistivity, rubber-like elasticity, and incombustibility of the silicone encapsulant resulted in the high durability of the modules. Our results indicate that silicone is an attractive encapsulation material, as it improves the long-term durability of crystalline Si PV modules.

Photovoltaic module certification and laboratory accreditation criteria development

NASA Astrophysics Data System (ADS)

Osterwald, Carl R.; Zerlaut, Gene; Hammond, Robert; D'Aiello, Robert

1996-01-01

This paper overviews a model product certification and test laboratory accreditation program for photovoltaic (PV) modules that was recently developed by the National Renewable Energy Laboratory and Arizona State University. The specific objective of this project was to produce a document that details the equipment, facilities, quality assurance procedures, and technical expertise an accredited laboratory needs for performance and qualification testing of PV modules, along with the specific tests needed for a module design to be certified. The document was developed in conjunction with a criteria development committee consisting of representatives from 30 U.S. PV manufacturers, end users, standards and codes organizations, and testing laboratories. The intent is to lay the groundwork for a future U.S. PV certification and accreditation program that will be beneficial to the PV industry as a whole.

State - Level Regulation's Effectiveness in Addressing Global Climate Change and Promoting Solar Energy Deployment

NASA Astrophysics Data System (ADS)

Peterman, Carla Joy

Paper 1, Local Solutions to Global Problems: Climate Change Policies and Regulatory Jurisdiction, considers the efficacy of various types of environmental regulations when they are applied locally to pollutants whose damages extend beyond the jurisdiction of the local regulators. Local regulations of a global pollutant may be ineffective if producers and consumers can avoid them by transacting outside the reach of the local regulator. In many cases, this may involve the physical relocation of the economic activity, a problem often referred to as "leakage." This paper highlights another way in which local policies can be circumvented: through the shuffling of who buys from whom. The paper maintains that the problems of reshuffling are exacerbated when the options for compliance with the regulations are more flexible. Numerical analyses is presented demonstrating that several proposed policies to limit greenhouse gas emissions from the California electricity sector may have very little effect on carbon emissions if they are applied only within that state. Paper 1 concludes that although local subsidies for energy efficiency, renewable electricity, and transportation biofuels constitute attempts to pick technology winners, they may be the only mechanisms that local jurisdictions, acting alone, have at their disposal to address climate change. Paper 2, Pass-Through of Solar PV Incentives to Consumers: The Early Years of California's Solar PV Incentives, examines the pass through of incentives to California solar PV system owners. The full post-subsidy price consumers pay for solar power is a key metric of the success of solar PV incentive programs and of overall PV market performance. This study examines the early years of California's most recent wave of distributed solar PV incentives (2000-2008) to determine the pass-through of incentives. Examination of this period is both intellectually and pragmatically important due to the high level of incentives provided and subsequent high cost to ratepayers; policymakers' expectations that price declines accrue to consumers; and market structure characteristics that might contribute to incomplete pass-through. This analysis shows that incentive passthrough in the California residential solar PV programs was incomplete. Consumer prices declined 54 cents for every additional dollar of incentive received. A large share of the incentive is captured by the solar PV contractor or other actors in the solar PV supply chain. The finding of incomplete pass-through is persistent across specifications. The analysis also identifies a lower degree of incentive pass-through for consumers in the highest income zip codes. Whether expectations of incentives' pass-through align with reality is critically important in the beginning years of emerging clean energy technology programs since this can affect the likelihood of future government investments and public support. Given the often-held policy assumption that consumer prices are declining in response to incentives, it is useful for policymakers to understand the circumstances under which such an assumption may not hold. Paper 3, Testing the Boundaries of the Solar Photovoltaic Learning System, tests how the choice of experience curves' geographic and technology assumptions affect solar PV experience curve results. Historically, solar PV experience curves have assumed one experience curve represents both module and non-module learning and that this learning happens at a global scale. These assumptions may be inaccurate for solar PV since the learning system, and technology and geographic boundaries, are likely different between PV modules and non-module components. Using 2004 to 2008 PV system price data from 13 states, and a longer time series of PV price data for California, some evidence is found that cumulative capacity at the state level is a better predictor of non-module costs than U.S. or global capacity. This paper explores, but is unable to significantly determine, how knowledge spillovers from neighboring states can influence a state's non-module costs. Given data limitations, and limitations to the two-factor experience model methodology itself, it is not possible to conclusively determine the correct geographic boundary for the non-module learning system. Throughout the paper ways in which the experience curve model and data can be augmented to achieve a better estimation are discussed. 2.

Development and Testing of a Prototype Grid-Tied Photovoltaic Power System

NASA Technical Reports Server (NTRS)

Eichenberg, Dennis J.

2009-01-01

The NASA Glenn Research Center (GRC) has developed and tested a prototype 2 kW DC grid-tied photovoltaic (PV) power system at the Center. The PV system has generated in excess of 6700 kWh since operation commenced in July 2006. The PV system is providing power to the GRC grid for use by all. Operation of the prototype PV system has been completely trouble free. A grid-tied PV power system is connected directly to the utility distribution grid. Facility power can be obtained from the utility system as normal. The PV system is synchronized with the utility system to provide power for the facility, and excess power is provided to the utility. The project transfers space technology to terrestrial use via nontraditional partners. GRC personnel glean valuable experience with PV power systems that are directly applicable to various space power systems, and provide valuable space program test data. PV power systems help to reduce harmful emissions and reduce the Nation s dependence on fossil fuels. Power generated by the PV system reduces the GRC utility demand, and the surplus power aids the community. Present global energy concerns reinforce the need for the development of alternative energy systems. Modern PV panels are readily available, reliable, efficient, and economical with a life expectancy of at least 25 years. Modern electronics has been the enabling technology behind grid-tied power systems, making them safe, reliable, efficient, and economical with a life expectancy of at least 25 years. Based upon the success of the prototype PV system, additional PV power system expansion at GRC is under consideration. The prototype grid-tied PV power system was successfully designed and developed which served to validate the basic principles described, and the theoretical work that was performed. The report concludes that grid-tied photovoltaic power systems are reliable, maintenance free, long life power systems, and are of significant value to NASA and the community.

Supply Constraints Analysis | Energy Analysis | NREL

Science.gov Websites

module cost, and future price could be critical to the economic viability of this PV technology. Even constraints on future CdTe PV module deployment and found that: CdTe PV modules can remain cost-competitive and 4070 GW of annual CdTe production by 2030. Cost estimates were based on NREL's manufacturing cost

City and County Solar PV Training Program, Module 3: Detailed Site Evaluation, Project Validation, and Permitting

DOE Office of Scientific and Technical Information (OSTI.GOV)

Day, Megan H; Lisell, Lars J

This is the third of five training modules recorded for the City and County Solar PV Training Program. The program is focused on training local government staff in the PV procurement process. This module focuses on siting and permitting for both rooftop and larger, ground-mounted systems rand includes a link to a video.

High throughput manufacturing of thin-film CdTe photovoltaic modules. Annual subcontract report, 16 November 1993--15 November 1994

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sandwisch, D W

1995-11-01

This report describes work performed by Solar Cells, Inc. (SCI), under a 3-year subcontract to advance SCI`s PV manufacturing technologies, reduce module production costs, increase module performance, and provide the groundwork for SCI to expand its commercial production capacities. SCI will meet these objectives in three phases by designing, debugging, and operating a 20-MW/year, automated, continuous PV manufacturing line that produces 60-cm {times} 120-cm thin-film CdTe PV modules. This report describes tasks completed under Phase 1 of the US Department of Energy`s PV Manufacturing Technology program.

Simulation of Distributed PV Power Output in Oahu Hawaii

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lave, Matthew Samuel

2016-08-01

Distributed solar photovoltaic (PV) power generation in Oahu has grown rapidly since 2008. For applications such as determining the value of energy storage, it is important to have PV power output timeseries. Since these timeseries of not typically measured, here we produce simulated distributed PV power output for Oahu. Simulated power output is based on (a) satellite-derived solar irradiance, (b) PV permit data by neighborhood, and (c) population data by census block. Permit and population data was used to model locations of distributed PV, and irradiance data was then used to simulate power output. PV power output simulations are presentedmore » by sub-neighborhood polygons, neighborhoods, and for the whole island of Oahu. Summary plots of annual PV energy and a sample week timeseries of power output are shown, and a the files containing the entire timeseries are described.« less

The vital role of manufacturing quality in the reliability of PV modules

NASA Astrophysics Data System (ADS)

Rusch, Peter

2014-10-01

The influence of manufacturing quality on the reliability of PV modules coming out of today's factories has been, and is still, under estimated among investors and buyers. The main reason is perception. Contrary to popular belief, PV modules are not a commodity. Module quality does differ among module brands. Certification alone does not guarantee the quality or reliability of a module. Cost reductions in manufacturing have unequivocally affected module quality. And the use of new, cheaper materials has had a measureable impact on module reliability. The need for meaningful manufacturing quality standards has been understood by the leading technical institutions and important industry players. The fact that most leading PV panel manufacturers have been certified according to ISO 9001 has led to some level of improvement and higher effectiveness. The new ISO 9001 PV QMS standards will be a major step in providing a tool to assess PV manufacturers' quality management systems. The current lack of sufficient standards has still got a negative influence on the quality of modules being installed today. Today every manufacturer builds their modules in their own way with little standardization or adherence to quality processes and methods, which are commonplace in other manufacturing industries. Although photovoltaic technology is to a great extent mature, the way modules are being produced has changed significantly over the past few years and it continues to change at a rapid pace. Investors, financiers and lenders stand the most to gain from PV systems over the long-term, but also the most to lose. Investors, developers, EPC, O&M and solar asset management companies must all manage manufacturing quality more proactively or they will face unexpected risks and failures down the road. Manufacturing quality deserves more transparency and attention, as it is a major driver of module performance and reliability. This paper will explain the benefits of good manufacturing quality and the dangers in poor manufacturing quality. The paper also explains why buyers and long-term investors need to pay close attention to the day-to-day manufacturing quality of module manufacturers. We demonstrate how these quality risks can be assessed and mitigated by independent diligence, professional contracting and smart quality assurance processes that can be easily built into any module procurement process. We highlight the steps to ensure that every module used in a PV system is built to quality standards that support the long-term reliability of a PV system.

Lightweight, Flexible Solar Cells on Stainless Steel Foil and Polymer for Space and Stratospheric Applications

NASA Technical Reports Server (NTRS)

Beernink, Kevin; Guha, Subhendu; Yang, Jeff; Banerjee, Arindam; Lord, Ken; DeMaggio, Greg; Liu, Frank; Pietka, Ginger; Johnson, Todd; Reinhout, Melanie;

Comparison between two photovoltaic module models based on transistors

NASA Astrophysics Data System (ADS)

Saint-Eve, Frédéric; Sawicki, Jean-Paul; Petit, Pierre; Maufay, Fabrice; Aillerie, Michel

2018-05-01

The main objective of this paper is to verify the possibility to reduce to a simple electronic circuit with very few components the behavior simulation of an un-shaded photovoltaic (PV) module. Particularly, two models based on well-tried elementary structures, i.e., the Darlington structure in first model and the voltage regulation with programmable Zener diode in the second are analyzed. Specifications extracted from the behavior of a real I-V characteristic of a panel are considered and the principal electrical variables are deduced. The two models are expected to match with open circuit voltage, maximum power point (MPP) and short circuit current, without forgetting realistic current slopes on the both sides of MPP. The robustness is mentioned when irradiance varies and is considered as an additional fundamental property. For both models, two simulations are done to identify influence of some parameters. In the first model, a parameter allowing to adjust current slope on left side of MPP proves to be also important for the calculation of open circuit voltage. Besides this model does not authorize an entirely adjustment of I-V characteristic and MPP moves significantly away from real value when irradiance increases. On the contrary, the second model seems to have only qualities: open circuit voltage is easy to calculate, current slopes are realistic and there is perhaps a good robustness when irradiance variations are simulated by adjusting short circuit current of PV module. We have shown that these two simplified models are expected to make reliable and easier simulations of complex PV architecture integrating many different devices like PV modules or other renewable energy sources and storage capacities coupled in parallel association.

A photovoltaic-driven and energy-autonomous CMOS implantable sensor.

PubMed

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.

Volume holographic lens spectrum-splitting photovoltaic system for high energy yield with direct and diffuse solar illumination

NASA Astrophysics Data System (ADS)

Chrysler, Benjamin D.; Wu, Yuechen; Yu, Zhengshan; Kostuk, Raymond K.

2017-08-01

In this paper a prototype spectrum-splitting photovoltaic system based on volume holographic lenses (VHL) is designed, fabricated and tested. In spectrum-splitting systems, incident sunlight is divided in spectral bands for optimal conversion by a set of single-junction PV cells that are laterally separated. The VHL spectrumsplitting system in this paper has a form factor similar to conventional silicon PV modules but with higher efficiencies (>30%). Unlike many other spectrum-splitting systems that have been proposed in the past, the system in this work converts both direct and diffuse sunlight while using inexpensive 1-axis tracking systems. The VHL system uses holographic lenses that focus light at a transition wavelength to the boundary between two PV cells. Longer wavelength light is dispersed to the narrow bandgap cell and shorter wavelength light to the wide bandgap cell. A prototype system is designed with silicon and GaAs PV cells. The holographic lenses are fabricated in Covestro Bayfol HX photopolymer by `stitching' together lens segments through sequential masked exposures. The PV cells and holographic lenses were characterized and the data was used in a raytrace simulation and predicts an improvement in total power output of 15.2% compared to a non-spectrum-splitting reference. A laboratory measurement yielded an improvement in power output of 8.5%.

Development of an operation strategy for hydrogen production using solar PV energy based on fluid dynamic aspects

NASA Astrophysics Data System (ADS)

Amores, Ernesto; Rodríguez, Jesús; Oviedo, José; de Lucas-Consuegra, Antonio

2017-06-01

Alkaline water electrolysis powered by renewable energy sources is one of the most promising strategies for environmentally friendly hydrogen production. However, wind and solar energy sources are highly dependent on weather conditions. As a result, power fluctuations affect the electrolyzer and cause several negative effects. Considering these limiting effects which reduce the water electrolysis efficiency, a novel operation strategy is proposed in this study. It is based on pumping the electrolyte according to the current density supplied by a solar PV module, in order to achieve the suitable fluid dynamics conditions in an electrolysis cell. To this aim, a mathematical model including the influence of electrode-membrane distance, temperature and electrolyte flow rate has been developed and used as optimization tool. The obtained results confirm the convenience of the selected strategy, especially when the electrolyzer is powered by renewable energies.

An investigation of the maximum penetration level of a photovoltaic (PV) system into a traditional distribution grid

NASA Astrophysics Data System (ADS)

Chalise, Santosh

Although solar photovoltaic (PV) systems have remained the fastest growing renewable power generating technology, variability as well as uncertainty in the output of PV plants is a significant issue. This rapid increase in PV grid-connected generation presents not only progress in clean energy but also challenges in integration with traditional electric power grids which were designed for transmission and distribution of power from central stations. Unlike conventional electric generators, PV panels do not have rotating parts and thus have no inertia. This potentially causes a problem when the solar irradiance incident upon a PV plant changes suddenly, for example, when scattered clouds pass quickly overhead. The output power of the PV plant may fluctuate nearly as rapidly as the incident irradiance. These rapid power output fluctuations may then cause voltage fluctuations, frequency fluctuations, and power quality issues. These power quality issues are more severe with increasing PV plant power output. This limits the maximum power output allowed from interconnected PV plants. Voltage regulation of a distribution system, a focus of this research, is a prime limiting factor in PV penetration levels. The IEEE 13-node test feeder, modeled and tested in the MATLAB/Simulink environment, was used as an example distribution feeder to analyze the maximum acceptable penetration of a PV plant. The effect of the PV plant's location was investigated, along with the addition of a VAR compensating device (a D-STATCOM in this case). The results were used to develop simple guidelines for determining an initial estimate of the maximum PV penetration level on a distribution feeder. For example, when no compensating devices are added to the system, a higher level of PV penetration is generally achieved by installing the PV plant close to the substation. The opposite is true when a VAR compensator is installed with the PV plant. In these cases, PV penetration levels over 50% may be safely achieved.

Photovoltaic module and module arrays

DOEpatents

Botkin, Jonathan; Graves, Simon; Lenox, Carl J. S.; Culligan, Matthew; Danning, Matt

2013-08-27

A photovoltaic (PV) module including a PV device and a frame, The PV device has a PV laminate defining a perimeter and a major plane. The frame is assembled to and encases the laminate perimeter, and includes leading, trailing, and side frame members, and an arm that forms a support face opposite the laminate. The support face is adapted for placement against a horizontal installation surface, to support and orient the laminate in a non-parallel or tilted arrangement. Upon final assembly, the laminate and the frame combine to define a unitary structure. The frame can orient the laminate at an angle in the range of 3.degree.-7.degree. from horizontal, and can be entirely formed of a polymeric material. Optionally, the arm incorporates integral feature(s) that facilitate interconnection with corresponding features of a second, identically formed PV module.

Photovoltaic module and module arrays

DOEpatents

Botkin, Jonathan [El Cerrito, CA; Graves, Simon [Berkeley, CA; Lenox, Carl J. S. [Oakland, CA; Culligan, Matthew [Berkeley, CA; Danning, Matt [Oakland, CA

2012-07-17

A photovoltaic (PV) module including a PV device and a frame. The PV device has a PV laminate defining a perimeter and a major plane. The frame is assembled to and encases the laminate perimeter, and includes leading, trailing, and side frame members, and an arm that forms a support face opposite the laminate. The support face is adapted for placement against a horizontal installation surface, to support and orient the laminate in a non-parallel or tilted arrangement. Upon final assembly, the laminate and the frame combine to define a unitary structure. The frame can orient the laminate at an angle in the range of 3.degree.-7.degree. from horizontal, and can be entirely formed of a polymeric material. Optionally, the arm incorporates integral feature(s) that facilitate interconnection with corresponding features of a second, identically formed PV module.

Top Five Large-Scale Solar Myths | State, Local, and Tribal Governments |

Science.gov Websites

of large-scale photovoltaic (PV) facilities or solar farms tend to include a myriad of misperceptions technologies do use mirrors which can cause glare, most solar farms use PV modules to generate electricity. PV panels in order to convert solar energy into electricity. PV modules are generally less reflective than

Photovoltaic power generation; Proceedings of the EC Contractors' Meeting, Hamburg, West Germany, July 12, 13, 1983

NASA Astrophysics Data System (ADS)

Palz, W.

Several operational examples of photovoltaic (PV) power generation systems in Europe are described. The systems include: a 300 kW power plant in Pellworm, West Germany; the Tremiti desalination plant in Tremiti, Italy; and the Kythnos PV power plant in Kythnos, Greece. Consideration is also given to a PV-powered swimming pool heating system in Chevretogne, Belgium; a rural electrification program using PV power plants in French Guyana; a solar-wind project on Terschelling Island, the Netherlands; and a PV power plant for hydrogen production and water pumping in Hoboken, Belgium. A 30-kW power station in Marchwood, England and the Nice airport survey and control system are also cited as examples of successful PV power generation systems.

NREL Photovoltaic Program FY 1995 annual report

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1996-06-01

This report summarizes the in-house and subcontracted R&D activities from Oct. 1994 through Sept. 1995; their objectives are to conduct basic, applied, and engineering research, manage subcontracted R&D projects, perform research complementary to subcontracted work, develop and maintain state-of-the-art measurement and device capabilities, develop PV manufacturing technology and modules, transfer results to industry, and evolve viable partnerships for PV systems and market development. The research activities are grouped into 5 sections: crystalline Si and advanced devices, thin-film PV, PV manufacturing, PV module and system performance and engineering, and PV applications and market development.

Comparison of four MPPT techniques for PV systems

NASA Astrophysics Data System (ADS)

Atik, L.; Petit, P.; Sawicki, J. P.; Ternifi, Z. T.; Bachir, G.; Aillerie, M.

2016-07-01

The working behavior of a module / PV array is non-linear and highly dependent on working conditions. As a given condition, there is only one point at which the level of available power at its output is maximum. This point varies with time, enlightenment and temperature. To ensure optimum operation, the use of MPPT control allows us to extract the maximum power. This paper presents a comparative study of four widely-adopted MPPT algorithms, such as Perturb and Observe, Incremental Conductance, Measurements of the variation of the open circuit voltage or of the short-circuit current. Their performance is evaluated using, for all these techniques. In particular, this study compares the behaviors of each technique in presence of solar irradiation variations and temperature fluctuations. These MPPT techniques will be compared using the Matlab / Simulink tool.

Design of a Glenn Research Center Solar Field Grid-Tied Photovoltaic Power System

NASA Technical Reports Server (NTRS)

Eichenberg, Dennis J.

2009-01-01

The NASA Glenn Research Center (GRC) designed, developed, and installed, a 37.5 kW DC photovoltaic (PV) Solar Field in the GRC West Area in the 1970s for the purpose of testing PV panels for various space and terrestrial applications. The PV panels are arranged to provide a nominal 120 VDC. The GRC Solar Field has been extremely successful in meeting its mission. The PV panels and the supporting electrical systems are all near their end of life. GRC has designed a 72 kW DC grid-tied PV power system to replace the existing GRC West Area Solar Field. The 72 kW DC grid-tied PV power system will provide DC solar power for GRC PV testing applications, and provide AC facility power for all times that research power is not required. A grid-tied system is connected directly to the utility distribution grid. Facility power can be obtained from the utility system as normal. The PV system is synchronized with the utility system to provide power for the facility, and excess power is provided to the utility for use by all. The project transfers space technology to terrestrial use via nontraditional partners. GRC personnel glean valuable experience with PV power systems that are directly applicable to various space power systems, and provide valuable space program test data. PV power systems help to reduce harmful emissions and reduce the Nation s dependence on fossil fuels. Power generated by the PV system reduces the GRC utility demand, and the surplus power aids the community. Present global energy concerns reinforce the need for the development of alternative energy systems. Modern PV panels are readily available, reliable, efficient, and economical with a life expectancy of at least 25 years. Modern electronics has been the enabling technology behind grid-tied power systems, making them safe, reliable, efficient, and economical with a life expectancy of at least 25 years. The report concludes that the GRC West Area grid-tied PV power system design is viable for a reliable, maintenance free, long life power system that is of significant value to NASA and the community.

An analytical-numerical approach for parameter determination of a five-parameter single-diode model of photovoltaic cells and modules

NASA Astrophysics Data System (ADS)

Hejri, Mohammad; Mokhtari, Hossein; Azizian, Mohammad Reza; Söder, Lennart

2016-04-01

Parameter extraction of the five-parameter single-diode model of solar cells and modules from experimental data is a challenging problem. These parameters are evaluated from a set of nonlinear equations that cannot be solved analytically. On the other hand, a numerical solution of such equations needs a suitable initial guess to converge to a solution. This paper presents a new set of approximate analytical solutions for the parameters of a five-parameter single-diode model of photovoltaic (PV) cells and modules. The proposed solutions provide a good initial point which guarantees numerical analysis convergence. The proposed technique needs only a few data from the PV current-voltage characteristics, i.e. open circuit voltage Voc, short circuit current Isc and maximum power point current and voltage Im; Vm making it a fast and low cost parameter determination technique. The accuracy of the presented theoretical I-V curves is verified by experimental data.

On the Path to SunShot - The Role of Advancements in Solar Photovoltaic Efficiency, Reliability, and Costs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Woodhouse, Michael; Jones-Albertus, Rebecca; Feldman, David

2016-05-01

Although tremendous progress has been made in reducing the cost of PV systems, additional LCOE reductions of 40%–50% between 2015 and 2020 will be required to reach the SunShot Initiative’s targets (see Woodhouse et al. 2016). Understanding the tradeoffs between installed prices and other PV system characteristics—such as module efficiency, module degradation rate, and system lifetime—are vital. For example, with 29%-efficient modules and high reliability (a 50-year lifetime and a 0.2%/year module degradation rate), a residential PV system could achieve the SunShot LCOE goal with modules priced at almost $1.20/W. But change the lifetime to 10 years and the degradationmore » rate to 2%/year, and the system would need those very high-efficiency modules at zero cost to achieve the same LCOE. Although these examples are extreme, they serve to illustrate the wide range of technological combinations that could help drive PV toward the LCOE goals. SunShot’s PV roadmaps illustrate specific potential pathways to the target cost reductions.« less

Specific energy yield comparison between crystalline silicon and amorphous silicon based PV modules

NASA Astrophysics Data System (ADS)

Ferenczi, Toby; Stern, Omar; Hartung, Marianne; Mueggenburg, Eike; Lynass, Mark; Bernal, Eva; Mayer, Oliver; Zettl, Marcus

2009-08-01

As emerging thin-film PV technologies continue to penetrate the market and the number of utility scale installations substantially increase, detailed understanding of the performance of the various PV technologies becomes more important. An accurate database for each technology is essential for precise project planning, energy yield prediction and project financing. However recent publications showed that it is very difficult to get accurate and reliable performance data of theses technologies. This paper evaluates previously reported claims the amorphous silicon based PV modules have a higher annual energy yield compared to crystalline silicon modules relative to their rated performance. In order to acquire a detailed understanding of this effect, outdoor module tests were performed at GE Global Research Center in Munich. In this study we examine closely two of the five reported factors that contribute to enhanced energy yield of amorphous silicon modules. We find evidence to support each of these factors and evaluate their relative significance. We discuss aspects for improvement in how PV modules are sold and identify areas for further study further study.

NREL to Lead New Consortium to Improve Reliability and Performance of Solar

Science.gov Websites

for photovoltaics (PV) and lower the cost of electricity generated by solar power. The Durable Module the cost of electricity from photovoltaics." The Energy Department's Office of Energy Efficiency , DuraMat will address the substantial opportunities that exist for durable, high-performance, low-cost

Study of the electrical and thermal performances of photovoltaic thermal collector-compound parabolic concentrated

NASA Astrophysics Data System (ADS)

Jaaz, Ahed Hameed; Sopian, Kamaruzzaman; Gaaz, Tayser Sumer

2018-06-01

The importance of utilizing the solar energy as a very suitable source among multi-source approaches to replace the conventional energy is on the rise in the last four decades. The invention of the photovoltaic module (PV) could be the corner stone in this process. However, the limited amount of energy obtained from PV was and still the main challenge of full utilization of the solar energy. In this paper, the use of the compound parabolic concentrator (CPC) along with the thermal photovoltaic module (PVT) where the cooling process of the CPC is conducted using a novel technique of water jet impingement has applied experimentally and physically tested. The test includes the effect of water jet impingement on the total power, electrical efficiency, thermal efficiency, and total efficiency on CPC-PVT system. The cooling process at the maximum irradiation by water jet impingement resulted in improving the electrical efficiency by 7%, total output power by 31% and the thermal efficiency by 81%. These results outperform the recent highest results recorded by the most recent work.

Chapter 11.2: Inverters, Power Optimizers, and Microinverters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deline, Christopher A

Inverters span a wide range of sizes, topologies, and connection voltages: from utility-scale megawatt inverters to string inverters. Switch-mode power conversion relies on high frequency chopping of DC signal to periodically charge and discharge energy storage elements, such as inductors and capacitors. Additional circuit components are required to address practical issues in inverters such as voltage ripple and harmonic distortion. Inverters are beginning to incorporate components with a bandgap above should be 3 eV, such as SiC and GaN. Photovoltaic (PV) modules respond dynamically to changing temperature and irradiation conditions. Thus, maximum DC power extraction requires periodic adjustment of themore » PV voltage and current operating point. An inverter's total efficiency is measured by the product of its conversion efficiency and the maximum-power-point tracking (MPPT) efficiency. This chapter lists the primary functions of inverters that include auxiliary capabilities, such as monitoring of DC and AC performance, and other error reporting.« less

A Single-Phase Current Source Solar Inverter with Constant Instantaneous Power, Improved Reliability, and Reduced-Size DC-Link Filter

NASA Astrophysics Data System (ADS)

Bush, Craig R.

This dissertation presents a novel current source converter topology that is primarily intended for single-phase photovoltaic (PV) applications. In comparison with the existing PV inverter technology, the salient features of the proposed topology are: a) the low frequency (double of line frequency) ripple that is common to single-phase inverters is greatly reduced; b) the absence of low frequency ripple enables significantly reduced size pass components to achieve necessary DC-link stiffness and c) improved maximum power point tracking (MPPT) performance is readily achieved due to the tightened current ripple even with reduced-size passive components. The proposed topology does not utilize any electrolytic capacitors. Instead an inductor is used as the DC-link filter and reliable AC film capacitors are utilized for the filter and auxiliary capacitor. The proposed topology has a life expectancy on par with PV panels. The proposed modulation technique can be used for any current source inverter where an unbalanced three-phase operation is desires such as active filters and power controllers. The proposed topology is ready for the next phase of microgrid and power system controllers in that it accepts reactive power commands. This work presents the proposed topology and its working principle supported by with numerical verifications and hardware results. Conclusions and future work are also presented.

A MPPT Algorithm Based PV System Connected to Single Phase Voltage Controlled Grid

NASA Astrophysics Data System (ADS)

Sreekanth, G.; Narender Reddy, N.; Durga Prasad, A.; Nagendrababu, V.

2012-10-01

Future ancillary services provided by photovoltaic (PV) systems could facilitate their penetration in power systems. In addition, low-power PV systems can be designed to improve the power quality. This paper presents a single-phase PV systemthat provides grid voltage support and compensation of harmonic distortion at the point of common coupling thanks to a repetitive controller. The power provided by the PV panels is controlled by a Maximum Power Point Tracking algorithm based on the incremental conductance method specifically modified to control the phase of the PV inverter voltage. Simulation and experimental results validate the presented solution.

Quantifying Reliability - The Next Step for a Rapidly Maturing PV Industry and China's Role

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, Sarah

2015-10-14

PV customers wish to know how long their PV modules will last, but quantitatively predicting service life is difficult because of the large number of ways that a module can fail, the variability of the use environment, the cost of the testing, and the short product development time, especially when compared with the long desired lifetime. China should play a key role in developing international standards because China manufactures most of the world's PV modules. The presentation will describe the steps that need to be taken to create a service life prediction within the context of a defined bill ofmore » materials, process window and use environment. Worldwide standards for cost-effective approaches to service-life predictions will be beneficial to both PV customers and manufacturers since the consequences of premature module failure can be disastrous for both.« less

SMART empirical approaches for predicting field performance of PV modules from results of reliability tests

NASA Astrophysics Data System (ADS)

Hardikar, Kedar Y.; Liu, Bill J. J.; Bheemreddy, Venkata

2016-09-01

Gaining an understanding of degradation mechanisms and their characterization are critical in developing relevant accelerated tests to ensure PV module performance warranty over a typical lifetime of 25 years. As newer technologies are adapted for PV, including new PV cell technologies, new packaging materials, and newer product designs, the availability of field data over extended periods of time for product performance assessment cannot be expected within the typical timeframe for business decisions. In this work, to enable product design decisions and product performance assessment for PV modules utilizing newer technologies, Simulation and Mechanism based Accelerated Reliability Testing (SMART) methodology and empirical approaches to predict field performance from accelerated test results are presented. The method is demonstrated for field life assessment of flexible PV modules based on degradation mechanisms observed in two accelerated tests, namely, Damp Heat and Thermal Cycling. The method is based on design of accelerated testing scheme with the intent to develop relevant acceleration factor models. The acceleration factor model is validated by extensive reliability testing under different conditions going beyond the established certification standards. Once the acceleration factor model is validated for the test matrix a modeling scheme is developed to predict field performance from results of accelerated testing for particular failure modes of interest. Further refinement of the model can continue as more field data becomes available. While the demonstration of the method in this work is for thin film flexible PV modules, the framework and methodology can be adapted to other PV products.

Parvalbumin Cell Ablation of NMDA-R1 Causes Increased Resting Network Excitability with Associated Social and Self-Care Deficits

PubMed Central

Billingslea, Eddie N; Tatard-Leitman, Valerie M; Anguiano, Jaynie; Jutzeler, Catherine R; Suh, Jimmy; Saunders, John A; Morita, Susumu; Featherstone, Robert E; Ortinski, Pavel I; Gandal, Michael J; Lin, Robert; Liang, Yuling; Gur, Raquel E; Carlson, Gregory C; Hahn, Chang-Gyu; Siegel, Steven J

2014-01-01

NMDA-receptor (NMDAR) hypofunction is strongly implicated in the pathophysiology of schizophrenia. Several convergent lines of evidence suggest that net excitation propagated by impaired NMDAR signaling on GABAergic interneurons may be of particular interest in mediating several aspects of schizophrenia. However, it is unclear which behavioral domains are governed by a net increase of excitation and whether modulating downstream GABAergic signaling can reverse neural and thus behavioral deficits. The current study determines the selective contributions of NMDAR dysfunction on PV-containing interneurons to electrophysiological, cognitive, and negative-symptom-related behavioral phenotypes of schizophrenia using mice with a PVcre-NR1flox-driven ablation of NR1 on PV-containing interneurons. In addition, we assessed the efficacy of one agent that directly modulates GABAergic signaling (baclofen) and one agent that indirectly modifies NMDAR-mediated signaling through antagonism of mGluR5 receptors (2-methyl-6-(phenylethynyl) pyridine (MPEP)). The data indicate that loss of NMDAR function on PV interneurons impairs self-care and sociability while increasing N1 latency and baseline gamma power, and reducing induction and maintenance of long-term potentiation. Baclofen normalized baseline gamma power without corresponding effects on behavior. MPEP further increased N1 latency and reduced social behavior in PVcre/NR1+/+ mice. These two indices were negatively correlated before and following MPEP such that as N1 latency increases, sociability decreases. This finding suggests a predictive role for N1 latency with respect to social function. Although previous data suggest that MPEP may be beneficial for core features of autism spectrum disorders, current data suggest that such effects require intact function of NMDAR on PV interneurons. PMID:24525709

Active power control of solar PV generation for large interconnection frequency regulation and oscillation damping

DOE PAGES

Liu, Yong; Zhu, Lin; Zhan, Lingwei; ...

2015-06-23

Because of zero greenhouse gas emission and decreased manufacture cost, solar photovoltaic (PV) generation is expected to account for a significant portion of future power grid generation portfolio. Because it is indirectly connected to the power grid via power electronic devices, solar PV generation system is fully decoupled from the power grid, which will influence the interconnected power grid dynamic characteristics as a result. In this study, the impact of solar PV penetration on large interconnected power system frequency response and inter-area oscillation is evaluated, taking the United States Eastern Interconnection (EI) as an example. Furthermore, based on the constructedmore » solar PV electrical control model with additional active power control loops, the potential contributions of solar PV generation to power system frequency regulation and oscillation damping are examined. The advantages of solar PV frequency support over that of wind generator are also discussed. Finally, simulation results demonstrate that solar PV generations can effectively work as ‘actuators’ in alleviating the negative impacts they bring about.« less

Photovoltaic-Model-Based Solar Irradiance Estimators: Performance Comparison and Application to Maximum Power Forecasting

NASA Astrophysics Data System (ADS)

Scolari, Enrica; Sossan, Fabrizio; Paolone, Mario

2018-01-01

Due to the increasing proportion of distributed photovoltaic (PV) production in the generation mix, the knowledge of the PV generation capacity has become a key factor. In this work, we propose to compute the PV plant maximum power starting from the indirectly-estimated irradiance. Three estimators are compared in terms of i) ability to compute the PV plant maximum power, ii) bandwidth and iii) robustness against measurements noise. The approaches rely on measurements of the DC voltage, current, and cell temperature and on a model of the PV array. We show that the considered methods can accurately reconstruct the PV maximum generation even during curtailment periods, i.e. when the measured PV power is not representative of the maximum potential of the PV array. Performance evaluation is carried out by using a dedicated experimental setup on a 14.3 kWp rooftop PV installation. Results also proved that the analyzed methods can outperform pyranometer-based estimations, with a less complex sensing system. We show how the obtained PV maximum power values can be applied to train time series-based solar maximum power forecasting techniques. This is beneficial when the measured power values, commonly used as training, are not representative of the maximum PV potential.

Single-Phase Single-Stage Grid Tied Solar PV System with Active Power Filtering Using Power Balance Theory

NASA Astrophysics Data System (ADS)

Singh, Yashi; Hussain, Ikhlaq; Singh, Bhim; Mishra, Sukumar

2018-06-01

In this paper, power quality features such as harmonics mitigation, power factor correction with active power filtering are addressed in a single-stage, single-phase solar photovoltaic (PV) grid tied system. The Power Balance Theory (PBT) with perturb and observe based maximum power point tracking algorithm is proposed for the mitigation of power quality problems in a solar PV grid tied system. The solar PV array is interfaced to a single phase AC grid through a Voltage Source Converter (VSC), which provides active power flow from a solar PV array to the grid as well as to the load and it performs harmonics mitigation using PBT based control. The solar PV array power varies with sunlight and due to this, the solar PV grid tied VSC works only 8-10 h per day. At night, when PV power is zero, the VSC works as an active power filter for power quality improvement, and the load active power is delivered by the grid to the load connected at the point of common coupling. This increases the effective utilization of a VSC. The system is modelled and simulated using MATLAB and simulated responses of the system at nonlinear loads and varying environmental conditions are also validated experimentally on a prototype developed in the laboratory.

Single-Phase Single-Stage Grid Tied Solar PV System with Active Power Filtering Using Power Balance Theory

NASA Astrophysics Data System (ADS)

Singh, Yashi; Hussain, Ikhlaq; Singh, Bhim; Mishra, Sukumar

2018-03-01

In this paper, power quality features such as harmonics mitigation, power factor correction with active power filtering are addressed in a single-stage, single-phase solar photovoltaic (PV) grid tied system. The Power Balance Theory (PBT) with perturb and observe based maximum power point tracking algorithm is proposed for the mitigation of power quality problems in a solar PV grid tied system. The solar PV array is interfaced to a single phase AC grid through a Voltage Source Converter (VSC), which provides active power flow from a solar PV array to the grid as well as to the load and it performs harmonics mitigation using PBT based control. The solar PV array power varies with sunlight and due to this, the solar PV grid tied VSC works only 8-10 h per day. At night, when PV power is zero, the VSC works as an active power filter for power quality improvement, and the load active power is delivered by the grid to the load connected at the point of common coupling. This increases the effective utilization of a VSC. The system is modelled and simulated using MATLAB and simulated responses of the system at nonlinear loads and varying environmental conditions are also validated experimentally on a prototype developed in the laboratory.

Spectrum sensitivity, energy yield, and revenue prediction of PV and CPV modules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kinsey, Geoffrey S., E-mail: Geoffrey.kinsey@ee.doe.gov

2015-09-28

Impact on module performance of spectral irradiance variation has been determined for III-V multijunctions compared against the four most common flat-plate module types (cadmium telluride, multicrystalline silicon, copper indium gallium selenide, and monocrystalline silicon. Hour-by-hour representative spectra were generated using atmospheric variables for Albuquerque, New Mexico, USA. Convolution with published values for external quantum efficiency gave the predicted current output. When combined with specifications of commercial PV modules, energy yield and revenue were predicted. This approach provides a means for optimizing PV module design based on various site-specific temporal variables.

Spectrum sensitivity, energy yield, and revenue prediction of PV and CPV modules

NASA Astrophysics Data System (ADS)

Kinsey, Geoffrey S.

2015-09-01

Impact on module performance of spectral irradiance variation has been determined for III-V multijunctions compared against the four most common flat-plate module types (cadmium telluride, multicrystalline silicon, copper indium gallium selenide, and monocrystalline silicon. Hour-by-hour representative spectra were generated using atmospheric variables for Albuquerque, New Mexico, USA. Convolution with published values for external quantum efficiency gave the predicted current output. When combined with specifications of commercial PV modules, energy yield and revenue were predicted. This approach provides a means for optimizing PV module design based on various site-specific temporal variables.

Grid-Tied Photovoltaic Power System

NASA Technical Reports Server (NTRS)

Eichenberg, Dennis J.

2011-01-01

A grid-tied photovoltaic (PV) power system is connected directly to the utility distribution grid. Facility power can be obtained from the utility system as normal. The PV system is synchronized with the utility system to provide power for the facility, and excess power is provided to the utility. Operating costs of a PV power system are low compared to conventional power technologies. This method can displace the highest-cost electricity during times of peak demand in most climatic regions, and thus reduce grid loading. Net metering is often used, in which independent power producers such as PV power systems are connected to the utility grid via the customers main service panels and meters. When the PV power system is generating more power than required at that location, the excess power is provided to the utility grid. The customer pays the net of the power purchased when the on-site power demand is greater than the onsite power production, and the excess power is returned to the utility grid. Power generated by the PV system reduces utility demand, and the surplus power aids the community. Modern PV panels are readily available, reliable, efficient, and economical, with a life expectancy of at least 25 years. Modern electronics have been the enabling technology behind grid-tied power systems, making them safe, reliable, efficient, and economical with a life expectancy equal to the modern PV panels. The grid-tied PV power system was successfully designed and developed, and this served to validate the basic principles developed, and the theoretical work that was performed. Grid-tied PV power systems are reliable, maintenance- free, long-life power systems, and are of significant value to NASA and the community. Of particular value are the analytical tools and capabilities that have been successfully developed. Performance predictions can be made confidently for grid-tied PV systems of various scales. The work was done under the NASA Hybrid Power Management (HPM) Program, which is the integration of diverse power devices in an optimal configuration for space and terrestrial applications.

Seventh workshop on the role of impurities and defects in silicon device processing

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1997-08-01

This workshop is the latest in a series which has looked at technological issues related to the commercial development and success of silicon based photovoltaic (PV) modules. PV modules based on silicon are the most common at present, but face pressure from other technologies in terms of cell performance and cell cost. This workshop addresses a problem which is a factor in the production costs of silicon based PV modules.

Economically Sustainable Scaling of Photovoltaics to Meet Climate Targets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Needleman, David Berney; Poindexter, Jeremy R.; Kurchin, Rachel C.

To meet climate goals, photovoltaics (PV) deployment will have to grow rapidly over the next fifteen years. We identify two barriers to this growth: scale-up of manufacturing capacity and the cost of PV module production. We explore several technoeconomic approaches to overcoming these barriers and identify deep reductions in the capital intensity (capex) of PV module manufacturing and large increases in module efficiency as the most promising routes to rapid deployment. Given the lag inherent in rolling out new technology, we explore an approach where growth is fueled by debt or subsidies in the short-term and technological advances in themore » medium term. Finally, we analyze the current capex structure of crystalline silicon PV module manufacturing to identify potential savings.« less

Analysis of typical world countries' wind power and PV industry policies and their enlightenment to China

NASA Astrophysics Data System (ADS)

Zeng, Ming; Yang, Lijun; Qiu, Hongji; Li, Yuanfei; Peng, Lilin

2017-01-01

The wind power and PV are the key fields of clean energy development in China in recent years. However, there are still many aspects of problems in wind power and PV industries at present, such as the insufficient consumptive ability and the limitation of market competition capability. The effective leading and support of government in the aspect of policies is especially needed in order to solve these problems. Based on the analysis of main policies system of wind power and PV in our country, Spain, the United Kingdom and Germany are chosen as typical countries because of their wind power and PV industries are relatively developed. Their policies of wind power and PV industries are studied respectively from five aspects, namely macroscopic laws, development planning, administrative policies, fiscal and tax policies and price policies. Then the comparison among typical countries and China is made and the exiting problems in China's policies of wind power and PV industries are summed up. Finally, the suggestions to promote China's wind power and PV industries development are presented.

76 FR 9766 - Nationwide Limited Public Interest Waiver Under Section 1605 (Buy American) of the American...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-22

... interest waiver), with respect to the following solar photo-voltaic (PV) equipment: (1) Domestically... utilized in a solar installation involving a U.S. manufactured PV module, or a module manufactured abroad... incidental and/or ancillary solar Photovoltaic (PV) equipment, when this equipment is utilized in solar...

Development and Testing of the Glenn Research Center Visitor's Center Grid-Tied Photovoltaic Power System

NASA Technical Reports Server (NTRS)

Eichenberg, Dennis J.

2009-01-01

The NASA Glenn Research Center (GRC) has developed, installed, and tested a 12 kW DC grid-tied photovoltaic (PV) power system at the GRC Visitor s Center. This system utilizes a unique ballast type roof mount for installing the photovoltaic panels on the roof of the Visitor s Center with no alterations or penetrations to the roof. The PV system has generated in excess of 15000 kWh since operation commenced in August 2008. The PV system is providing power to the GRC grid for use by all. Operation of the GRC Visitor s Center PV system has been completely trouble free. A grid-tied PV power system is connected directly to the utility distribution grid. Facility power can be obtained from the utility system as normal. The PV system is synchronized with the utility system to provide power for the facility, and excess power is provided to the utility. The project transfers space technology to terrestrial use via nontraditional partners. GRC personnel glean valuable experience with PV power systems that are directly applicable to various space power systems, and provides valuable space program test data. PV power systems help to reduce harmful emissions and reduce the Nation s dependence on fossil fuels. Power generated by the PV system reduces the GRC utility demand, and the surplus power aids the community. Present global energy concerns reinforce the need for the development of alternative energy systems. Modern PV panels are readily available, reliable, efficient, and economical with a life expectancy of at least 25 years. Modern electronics has been the enabling technology behind grid-tied power systems, making them safe, reliable, efficient, and economical with a life expectancy of at least 25 years. Based upon the success of the GRC Visitor s Center PV system, additional PV power system expansion at GRC is under consideration. The GRC Visitor s Center grid-tied PV power system was successfully designed and developed which served to validate the basic principles described, and the theoretical work that was performed. The report concludes that grid-tied photovoltaic power systems are reliable, maintenance free, long life power systems, and are of significant value to NASA and the community.

Short-term PV/T module temperature prediction based on PCA-RBF neural network

NASA Astrophysics Data System (ADS)

Li, Jiyong; Zhao, Zhendong; Li, Yisheng; Xiao, Jing; Tang, Yunfeng

2018-02-01

Aiming at the non-linearity and large inertia of temperature control in PV/T system, short-term temperature prediction of PV/T module is proposed, to make the PV/T system controller run forward according to the short-term forecasting situation to optimize control effect. Based on the analysis of the correlation between PV/T module temperature and meteorological factors, and the temperature of adjacent time series, the principal component analysis (PCA) method is used to pre-process the original input sample data. Combined with the RBF neural network theory, the simulation results show that the PCA method makes the prediction accuracy of the network model higher and the generalization performance stronger than that of the RBF neural network without the main component extraction.

Comparison of four MPPT techniques for PV systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Atik, L., E-mail: lotfi.atik@univ-usto.dz; Ternifi, Z. T.; Université de Lorraine, LMOPS, EA 4423, 57070 Metz

2016-07-25

The working behavior of a module / PV array is non-linear and highly dependent on working conditions. As a given condition, there is only one point at which the level of available power at its output is maximum. This point varies with time, enlightenment and temperature. To ensure optimum operation, the use of MPPT control allows us to extract the maximum power. This paper presents a comparative study of four widely-adopted MPPT algorithms, such as Perturb and Observe, Incremental Conductance, Measurements of the variation of the open circuit voltage or of the short-circuit current. Their performance is evaluated using, formore » all these techniques. In particular, this study compares the behaviors of each technique in presence of solar irradiation variations and temperature fluctuations. These MPPT techniques will be compared using the Matlab / Simulink tool.« less

Monitoring of the electrical parameters in off-grid solar power system

NASA Astrophysics Data System (ADS)

Idzkowski, Adam; Leoniuk, Katarzyna; Walendziuk, Wojciech

2016-09-01

The aim of this work was to make a monitoring dedicated to an off-grid installation. A laboratory set, which was built for that purpose, was equipped with a PV panel, a battery, a charge controller and a load. Additionally, to monitor electrical parameters from this installation there were used: LabJack module (data acquisition card), measuring module (self-built) and a computer with a program, which allows to measure and present the off-grid installation parameters. The program was made in G language using LabVIEW software. The designed system enables analyzing the currents and voltages of PV panel, battery and load. It makes also possible to visualize them on charts and to make reports from registered data. The monitoring system was also verified by a laboratory test and in real conditions. The results of this verification are also presented.

NREL/industry interaction: Amorphous silicon alloy research team formation

NASA Astrophysics Data System (ADS)

Luft, Werner

1994-06-01

The low material cost and proven manufacturability of amorphous silicon (a-Si) alloy photovoltaic technology make it ideally suited for large-scale terrestrial applications. The present efficiency of a-Si alloy modules is, however, much lower than the 15% stable efficiency that would lead to significant penetration of the electric utility bulk-power market. The slow progress in achieving high stabilized a-Si alloy module efficiencies may in part be attributed to the fact that only in the last few years did we emphasize stable efficiencies. A mission-focused integrated effort among the a-Si PV industry, universities, and the National Renewable Energy Laboratory (NREL) would help. To foster research integration, NREL has established four research teams with significant industry participation. In the 11 months since the research team formation, a close interaction among the a-Si PV industry, universities, and NREL has been achieved and has resulted in mission-directed research.

NREL/industry interaction: Amorphous silicon alloy research team formation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luft, W.

1994-06-30

The low material cost and proven manufacturability of amorphous silicon (a-Si) alloy photovoltaic technology make it ideally suited for large-scale terrestrial applications. The present efficiency of a-Si alloy modules is, however, much lower than the 15% stable efficiency that would lead to [ital significant] penetration of the electric utility bulk-power market. The slow progress in achieving high stabilized a-Si alloy module efficiencies may in part be attributed to the fact that only in the last few years did we emphasize stable efficiencies. A mission-focused integrated effort among the a-Si PV industry, universities, and the National Renewable Energy Laboratory (NREL) wouldmore » help. To foster research integration, NREL has established four research teams with significant industry participation. In the 11 months since the research team formation, a close interaction among the a-Si PV industry, universities, and NREL has been achieved and has resulted in mission-directed research.« less

Multiobjective Particle Swarm Optimization for the optimal design of photovoltaic grid-connected systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kornelakis, Aris

2010-12-15

Particle Swarm Optimization (PSO) is a highly efficient evolutionary optimization algorithm. In this paper a multiobjective optimization algorithm based on PSO applied to the optimal design of photovoltaic grid-connected systems (PVGCSs) is presented. The proposed methodology intends to suggest the optimal number of system devices and the optimal PV module installation details, such that the economic and environmental benefits achieved during the system's operational lifetime period are both maximized. The objective function describing the economic benefit of the proposed optimization process is the lifetime system's total net profit which is calculated according to the method of the Net Present Valuemore » (NPV). The second objective function, which corresponds to the environmental benefit, equals to the pollutant gas emissions avoided due to the use of the PVGCS. The optimization's decision variables are the optimal number of the PV modules, the PV modules optimal tilt angle, the optimal placement of the PV modules within the available installation area and the optimal distribution of the PV modules among the DC/AC converters. (author)« less

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

NASA Technical Reports Server (NTRS)

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.

Ultralight monolithic photovoltaic modules of amorphous silicon alloys

NASA Astrophysics Data System (ADS)

Hanak, J. J.

A process has been developed for fabrication of roll-up, monolithic, photovoltaic (PV) modules made of amorphous silicon (a-Si) alloys. They consist of tandem-junction solar cells deposited by a continuous, roll-to-roll process onto thin, foil substrates of bare metal, high temperature resin, or metal coated with insulators. They have the following characteristics: size, up to 71 cm x 30.5 cm; total thickness, 8 to 50 microns, power-to-weight and power-to-volume ratios at AM1, 2.4 kW/kg and 6.5 MW/cu m, respectively. Cells of a-Si alloys are up to 100 times as tolerant to irradiation with 1 MeV protons than crystalline cells and the damage is easily annealable. The modules have high power density and stability, they are portable, stowable, deployable, retractable, tolerant to radiation and meteorite or projectile impact, and attractive for terrestrial and aerospace applications.

Experimental Studies on the Flammability and Fire Hazards of Photovoltaic Modules

PubMed Central

Yang, Hong-Yun; Zhou, Xiao-Dong; Yang, Li-Zhong; Zhang, Tao-Lin

2015-01-01

Many of the photovoltaic (PV) systems on buildings are of sufficiently high voltages, with potential to cause or promote fires. However, research about photovoltaic fires is insufficient. This paper focuses on the flammability and fire hazards of photovoltaic modules. Bench-scale experiments based on polycrystalline silicon PV modules have been conducted using a cone calorimeter. Several parameters including ignition time (tig), mass loss, heat release rate (HRR), carbon monoxide (CO) and carbon dioxide (CO2) concentration, were investigated. The fire behaviours, fire hazards and toxicity of gases released by PV modules are assessed based on experimental results. The results show that PV modules under tests are inflammable with the critical heat flux of 26 kW/m2. This work will lead to better understanding on photovoltaic fires and how to help authorities determine the appropriate fire safety provisions for controlling photovoltaic fires. PMID:28793434

Experimental Studies on the Flammability and Fire Hazards of Photovoltaic Modules.

PubMed

Yang, Hong-Yun; Zhou, Xiao-Dong; Yang, Li-Zhong; Zhang, Tao-Lin

2015-07-09

Many of the photovoltaic (PV) systems on buildings are of sufficiently high voltages, with potential to cause or promote fires. However, research about photovoltaic fires is insufficient. This paper focuses on the flammability and fire hazards of photovoltaic modules. Bench-scale experiments based on polycrystalline silicon PV modules have been conducted using a cone calorimeter. Several parameters including ignition time ( t ig ), mass loss, heat release rate (HRR), carbon monoxide (CO) and carbon dioxide (CO₂) concentration, were investigated. The fire behaviours, fire hazards and toxicity of gases released by PV modules are assessed based on experimental results. The results show that PV modules under tests are inflammable with the critical heat flux of 26 kW/m². This work will lead to better understanding on photovoltaic fires and how to help authorities determine the appropriate fire safety provisions for controlling photovoltaic fires.

City and County Solar PV Training Program, Module 2: Screening and Identifying PV Projects

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elgqvist, Emma M

When screening and identifying PV projects, cities and counties should understand the different factors that impact the technical and economic potential of a PV project, the steps of the PV screening process, and how to use REopt Lite to screen a site for PV and storage project potential.

Development of an Advanced Grid-Connected PV-ECS System Considering Solar Energy Estimation

NASA Astrophysics Data System (ADS)

Rahman, Md. Habibur; Yamashiro, Susumu; Nakamura, Koichi

In this paper, the development and the performance of a viable distributed grid-connected power generation system of Photovoltaic-Energy Capacitor System (PV-ECS) considering solar energy estimation have been described. Instead of conventional battery Electric Double Layer Capacitors (EDLC) are used as storage device and Photovoltaic (PV) panel to generate power from solar energy. The system can generate power by PV, store energy when the demand of load is low and finally supply the stored energy to load during the period of peak demand. To realize the load leveling function properly the system will also buy power from grid line when load demand is high. Since, the power taken from grid line depends on the PV output power, a procedure has been suggested to estimate the PV output power by calculating solar radiation. In order to set the optimum value of the buy power, a simulation program has also been developed. Performance of the system has been studied for different load patterns in different weather conditions by using the estimated PV output power with the help of the simulation program.

Reliability and performance experience with flat-plate photovoltaic modules

NASA Technical Reports Server (NTRS)

Ross, R. G., Jr.

1982-01-01

Statistical models developed to define the most likely sources of photovoltaic (PV) array failures and the optimum method of allowing for the defects in order to achieve a 20 yr lifetime with acceptable performance degradation are summarized. Significant parameters were the cost of energy, annual power output, initial cost, replacement cost, rate of module replacement, the discount rate, and the plant lifetime. Acceptable degradation allocations were calculated to be 0.0001 cell failures/yr, 0.005 module failures/yr, 0.05 power loss/yr, a 0.01 rate of power loss/yr, and a 25 yr module wear-out length. Circuit redundancy techniques were determined to offset cell failures using fault tolerant designs such as series/parallel and bypass diode arrangements. Screening processes have been devised to eliminate cells that will crack in operation, and multiple electrical contacts at each cell compensate for the cells which escape the screening test and then crack when installed. The 20 yr array lifetime is expected to be achieved in the near-term.

Analysis of urban land use in the megacity of Dhaka, Bangladesh: Roof-top detection in the context of assessing solar photovoltaic potential

NASA Astrophysics Data System (ADS)

Jaegermeyr, J.; Kabir, H.; Endlicher, W.

2009-12-01

The megacity of Dhaka, Bangladesh is considered to be one of the world’s fastest growing urban centers. With nearly 14 million people Dhaka currently faces tremendous power crisis. The available power supply of Dhaka Megacity is currently 1000-1200 MW against the maximum demand of nearly 2000 MW. The objective of this study is to classify land cover of Dhaka to locate roof-top areas which are adequate for solar photovoltaic applications. Usually this task is performed with additional building-heights data. With lack of that, we present an object-based classification approach which is based on high resolution Quickbird data only. Extensive formal buildings in Dhaka mostly have flat roof-tops made from concrete which are well suited for PV applications. The classification is focused to detect these ‘Bright Roof-Tops’ to assess a lower limit for potential PV areas. With that conservative approach bright roof-top areas of 10.554 km2 out of the city’s 134.282 km2 could be found. The overall classification accuracy is 0.918, the producer’s accuracy of ‘Bright Roof-Tops’ is 0.833. Preliminary result of the PhD work of Humayun Kabir indicates that the application of only 75 Wp stand-alone solar modules on these available bright roof-tops can generate nearly 1,000 MW of electricity. The application of solar modules with high capacity (i.e., >200 Wp) preferably through grid-connected PV systems can substantially meet-up the city’s power demand, although several techno-economic and socio-political factors are certainly involved.

Evaluation of Mismatch Losses due to Shunts in industrial Silicon Photovoltaic Modules

NASA Astrophysics Data System (ADS)

Somasundaran, P.; Shilpi, M.; Gupta, R.

2017-05-01

In order to achieve higher efficiencies in photovoltaic module technology, it is important to characterize the shunts and other defects which degrade the performance of cells and modules as well as decrease their efficiency. These shunts also affect the reliability of cells and modules. It is important to understand how much fill factor and power loss is caused by the presence of shunts in the module. Shunts not only reduce the module power output, but also affect the I-V characteristics of the cell and hence the characteristics of the shunted cells are different from those of the shunt-free cells connected in the module leading to the mismatch effect. This is an interesting effect which has been systematically investigated in the present work. Moreover, the flow of increased shunt current will give rise to increased temperature in the region of shunt, which will affect the cell and hence module performance. In the present study, the distributed diode model has been extended to the module level and applied to evaluate the electrical mismatch losses and thermal mismatch losses due to shunts in industrial Silicon PV modules.

An analysis of the dust deposition on solar photovoltaic modules.

PubMed

Styszko, Katarzyna; Jaszczur, Marek; Teneta, Janusz; Hassan, Qusay; Burzyńska, Paulina; Marcinek, Ewelina; Łopian, Natalia; Samek, Lucyna

2018-03-29

Solid particles impair the performance of the photovoltaic (PV) modules. This results in power losses which lower the efficiency of the system as well as the increases of temperature which additionally decreases the performance and lifetime. The deposited dust chemical composition, concentration and formation of a dust layer on the PV surface differ significantly in reference to time and location. In this study, an evaluation of dust deposition on the PV front cover glass during the non-heating season in one of the most polluted European cities, Kraków, was performed. The time-dependent particle deposition and its correlation to the air pollution with particulate matter were analysed. Dust deposited on several identical PV modules during variable exposure periods (from 1 day up to 1 week) and the samples of total suspended particles (TSP) on quartz fibre filters using a low volume sampler were collected during the non-heating season in the period of 5 weeks. The concentration of TSP in the study period ranged between 12.5 and 60.05 μg m -3 while the concentration of PM10 observed in the Voivodeship Inspectorate of Environmental Protection traffic station, located 1.2 km from the TSP sampler, ranged from 14 to 47 μg m -3 . It was revealed that dust deposition density on a PV surface ranged from 7.5 to 42.1 mg m -2 for exposure periods of 1 day while the measured weekly dust deposition densities ranged from 25.8 to 277.0 mg m -2 . The precipitation volume and its intensity as well as humidity significantly influence the deposited dust. The rate of dust accumulation reaches approximately 40 mg m -2 day -1 in the no-precipitation period and it was at least two times higher than fluxes calculated on the basis of PM10 and TSP concentrations which suggest that additional forces such as electrostatic forces significantly influence dust deposition.

Fuzzy-PI-based centralised control of semi-isolated FP-SEPIC/ZETA BDC in a PV/battery hybrid system

NASA Astrophysics Data System (ADS)

Mahendran, Venmathi; Ramabadran, Ramaprabha

2016-11-01

Multiport converters with centralised controller have been most commonly used in stand-alone photovoltaic (PV)/battery hybrid system to supply the load smoothly without any disturbances. This study presents the performance analysis of four-port SEPIC/ZETA bidirectional converter (FP-SEPIC/ZETA BDC) using various types of centralised control schemes like Fuzzy tuned proportional integral controller (Fuzzy-PI), fuzzy logic controller (FLC) and conventional proportional integral (PI) controller. The proposed FP-SEPIC/ZETA BDC with various control strategy is derived for simultaneous power management of a PV source using distributed maximum power point tracking (DMPPT) algorithm, a rechargeable battery, and a load by means of centralised controller. The steady state and the dynamic response of the FP-SEPIC/ZETA BDC are analysed using three different types of controllers under line and load regulation. The Fuzzy-PI-based control scheme improves the dynamic response of the system when compared with the FLC and the conventional PI controller. The power balance between the ports is achieved by pseudorandom carrier modulation scheme. The response of the FP-SEPIC/ZETA BDC is also validated experimentally using hardware prototype model of 500 W system. The effectiveness of the control strategy is validated using simulation and experimental results.

A peaking-regulation-balance-based method for wind & PV power integrated accommodation

NASA Astrophysics Data System (ADS)

Zhang, Jinfang; Li, Nan; Liu, Jun

2018-02-01

Rapid development of China’s new energy in current and future should be focused on cooperation of wind and PV power. Based on the analysis of system peaking balance, combined with the statistical features of wind and PV power output characteristics, a method of comprehensive integrated accommodation analysis of wind and PV power is put forward. By the electric power balance during night peaking load period in typical day, wind power installed capacity is determined firstly; then PV power installed capacity could be figured out by midday peak load hours, which effectively solves the problem of uncertainty when traditional method hard determines the combination of the wind and solar power simultaneously. The simulation results have validated the effectiveness of the proposed method.

The application of encapsulation material stability data to photovoltaic module life assessment

NASA Technical Reports Server (NTRS)

Coulbert, C. D.

1983-01-01

For any piece of hardware that degrades when subject to environmental and application stresses, the route or sequence that describes the degradation process may be summarized in terms of six key words: LOADS, RESPONSE, CHANGE, DAMAGE, FAILURE, and PENALTY. Applied to photovoltaic modules, these six factors form the core outline of an expanded failure analysis matrix for unifying and integrating relevant material degradation data and analyses. An important feature of this approach is the deliberate differentiation between factors such as CHANGE, DAMAGE, and FAILURE. The application of this outline to materials degradation research facilitates the distinction between quantifying material property changes and quantifying module damage or power loss with their economic consequences. The approach recommended for relating material stability data to photovoltaic module life is to use the degree of DAMAGE to (1) optical coupling, (2) encapsulant package integrity, (3) PV circuit integrity or (4) electrical isolation as the quantitative criterion for assessing module potential service life rather than simply using module power loss.

Status of DOE and AID stand-alone photovoltaic system field tests

NASA Astrophysics Data System (ADS)

Bifano, W. J.; Delombard, R.; Ratajczak, A. F.; Scudder, L. R.

The NASA Lewis Research Center (LeRC) is managing stand-alone photovoltaic (PV) system projects sponsored by the U.S. Department of Energy (DOE) and the U.S. Agency for International Development (AID). The DOE project includes village PV power demonstration projects in Gabon (four sites) and the Marshall Islands, and PV-powered vaccine refrigerator systems in six countries. The AID project includes a large village power system, a farmhouse system and two water pumping-irrigation systems in Tunisia, a water pumping/grain grinding system in Upper Volta, five medical clinic systems in four countries, PV-powered vaccine refrigerator systems in 18 countries and a PV-powered remote earth station in Indonesia. This paper reviews these PV projects and summarizes significant findings to date.

Status of DOE and AID stand-alone photovoltaic system field tests

NASA Technical Reports Server (NTRS)

Bifano, W. J.; Delombard, R.; Ratajczak, A. F.; Scudder, L. R.

1984-01-01

The NASA Lewis Research Center (LeRC) is managing stand-alone photovoltaic (PV) system projects sponsored by the U.S. Department of Energy (DOE) and the U.S. Agency for International Development (AID). The DOE project includes village PV power demonstration projects in Gabon (four sites) and the Marshall Islands, and PV-powered vaccine refrigerator systems in six countries. The AID project includes a large village power system, a farmhouse system and two water pumping-irrigation systems in Tunisia, a water pumping/grain grinding system in Upper Volta, five medical clinic systems in four countries, PV-powered vaccine refrigerator systems in 18 countries and a PV-powered remote earth station in Indonesia. This paper reviews these PV projects and summarizes significant findings to date.

Will we exceed 50% efficiency in photovoltaics?

NASA Astrophysics Data System (ADS)

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 be sparsely packed leading to a ground efficiency, in the range of 10%, that in some cases will be below that of fixed modules of much lower cell efficiency. All this taken into account, High Concentration PV (HCPV) has the opportunity to become the cheapest of the PV technologies and beat the prevalent electricity generation technologies. Of course the way will be paved with challenges, and success is not guaranteed.

Performances and failure of field-aged PV modules operating in Saharan region of Algeria

NASA Astrophysics Data System (ADS)

Sadok, M.; Benyoucef, B.; Othmani, M.; Mehdaoui, A.

2016-07-01

This article deals with behaviour of PV modules, of different technologies and manufacturers, exposed for long periods in Saharan region of Algeria. These modules are exposed in Adrar in the south-western part of Algeria. The study uses experimental I-V curves of PV modules for determining their performances. The datasheet information of modules will be useful in determination of degradation rates of the modules. Three types of modules have been tested: Photowatt (PWX 500), UDTS-50 and Isofoton (I-75 and I-100 serials). Results showed that Isofoton I-100 modules present the highest degradation rate while the lowest degradation rate was reached with I-75 serial. However, these rates tallies with other studies. The visual inspection of the modules has revealed various kinds of failures and defects responsible of performances drop (EVA browning, delamination, burn marks,…).

Design and operation of grid-interactive thin-film silicon PV systems

NASA Astrophysics Data System (ADS)

Marion, Bill; Atmaram, Gobind; Lashway, Clin; Strachan, John W.

Results are described from the operation of 11 thin-film amorphous silicon photovoltaic systems at three test facilities: the Florida Solar Energy Center, the New Mexico Solar Energy Institute, and Sandia National Laboratories. Commercially available modules from four US manufacturers are used in these systems, with array sizes from 133 to 750 W peak. Measured array efficiencies are from 3.1 to 4.8 percent. Except for one manufacturer, array peak power is in agreement with the calculated design ratings. For certain grid-connected systems, nonoptimal operation exists because the array peak power voltage is below the lower voltage limit of the power conditioning system. Reliability problems are found in two manufacturers' modules when shorts to ground and terminal corrosion occur. Array leakage current data are presented.

DOE and AID stand-alone photovoltaic activities

NASA Technical Reports Server (NTRS)

Bifano, W. J.; Ratajczak, A. F.

1983-01-01

The NASA Lewis Research Center (LeRC) is managing stand-alone photovoltaic (PV) system activities sponsored by the U.S. Department of Energy (DOE) and the U.S. Agency for International Development (AID). The DOE project includes village PV power demonstration projects in Gabon (four sites) and the Marshall Islands, PV-powered medical refrigerators in six countries, PV system microprocessor control development activities and PV-hybrid system assessments. The AID project includes a large village system in Tunisia, a water pumping/grain grinding project in Upper Volta, five medical clinics in four countries, PV-powered remote earth station application. These PV activities and summarizes significant findings to data are reviewed.

Fundamental Studies of Adhesion of Dust to PV Module Surfaces: Chemical and Physical Relationships at the Microscale

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kazmerski, Lawrence L.; Diniz, Antonia Sonia A. C.; Maia, Cristiana Brasil

Photovoltaic (PV) module soiling is a growing area of concern for performance and reliability. This paper provides evaluations of the fundamental interactions of dust/soiling particles with several PV module surfaces. The purpose is to investigate the basic mechanisms involving the chemistry, morphology, and resulting particle adhesion to the first photon-incident surface. The evaluation and mapping of the chemistry and composition of single dust particles collected from operating PV module surfaces are presented. The first correlated direct measurements of the adhesive force of individual grains from field-operating collectors on identical PV module glass are reported, including correlations with specific compositions. Specialmore » microscale atomic force microscopy techniques are adapted to determine the force between the particle and the module glass surface. Results are presented for samples under dry and moisture-exposed conditions, confirming the effects of cementation for surfaces having soluble mineral and/or organic concentrations. Additionally, the effects of hydrocarbon fuels on the enhanced bonding of soiling particles to surfaces are determined for samples from urban and highly trafficked regions. Comparisons between glass and dust-mitigating superhydrophobic and superhydrophilic coatings are presented. Potential limitations of this proximal probe technique are discussed in terms of results and initial proof-of-concept experiments.« less

Final Technical Report for Automated Manufacturing of Innovative CPV/PV Modules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Okawa, David

Cogenra’s Dense Cell Interconnect system was designed to use traditional front-contact cells and string them together into high efficiency and high reliability “supercells”. This novel stringer allows one to take advantage of the ~100 GW/year of existing cell production capacity and create a solar product for the customer that will produce more power and last longer than traditional PV products. The goal for this program was for Cogenra Solar to design and develop a first-of-kind automated solar manufacturing line that produces strings of overlapping cells or “supercells” based on Cogenra’s Dense Cell Interconnect (DCI) technology for their Low Concentration Photovoltaicmore » (LCPV) systems. This will enable the commercialization of DCI technology to improve the efficiency, reliability and economics for their Low Concentration Photovoltaic systems. In this program, Cogenra Solar very successfully designed, developed, built, installed, and started up the ground-breaking manufacturing tools required to assemble supercells. Cogenra then successfully demonstrated operation of the integrated line at high yield and throughput far exceeding expectations. The development of a supercell production line represents a critical step toward a high volume and low cost Low Concentration Photovoltaic Module with Dense Cell Interconnect technology and has enabled the evaluation of the technology for reliability and yield. Unfortunately, performance and cost headwinds on Low Concentration Photovoltaics systems including lack of diffuse capture (10-15% hit) and more expensive tracker requirements resulted in a move away from LCPV technology. Fortunately, the versatility of Dense Cell Interconnect technology allows for application to flat plate module technology as well and Cogenra has worked with the DOE to utilize the learning from this grant to commercialize DCI technology for the solar market through the on-going grant: Catalyzing PV Manufacturing in the US With Cogenra Solar’s Next-Generation Dense Cell Interconnect PV Module Manufacturing Technology. This program is now very successfully building off of this work and commercializing the technology to enable increased solar adoption.« less

Research on Fault Characteristics and Line Protections Within a Large-scale Photovoltaic Power Plant

NASA Astrophysics Data System (ADS)

Zhang, Chi; Zeng, Jie; Zhao, Wei; Zhong, Guobin; Xu, Qi; Luo, Pandian; Gu, Chenjie; Liu, Bohan

2017-05-01

Centralized photovoltaic (PV) systems have different fault characteristics from distributed PV systems due to the different system structures and controls. This makes the fault analysis and protection methods used in distribution networks with distributed PV not suitable for a centralized PV power plant. Therefore, a consolidated expression for the fault current within a PV power plant under different controls was calculated considering the fault response of the PV array. Then, supported by the fault current analysis and the on-site testing data, the overcurrent relay (OCR) performance was evaluated in the collection system of an 850 MW PV power plant. It reveals that the OCRs at downstream side on overhead lines may malfunction. In this case, a new relay scheme was proposed using directional distance elements. In the PSCAD/EMTDC, a detailed PV system model was built and verified using the on-site testing data. Simulation results indicate that the proposed relay scheme could effectively solve the problems under variant fault scenarios and PV plant output levels.

Photovoltaic (PV) Systems Comparison at Fort Hood

DTIC Science & Technology

2010-06-01

Monocrystalline PV panels • Energy Photovoltaics, EPV-42 Solar Modules: Thin film PV panels • OutBack Flexware PV Advanced Photovoltaic Combiner...energy for an administrative building – Compare the performance between two different PV technologies: thin film and crystalline PV panels • Demo Team...Center for Energy and Environment PV Technology • Monocrystalline silicon1 • Thin film2 1 “About Solar,” DBK Corporation, http://www.dbksolar.com

Present Status and Future Prospects of Silicon Thin-Film Solar Cells

NASA Astrophysics Data System (ADS)

Konagai, Makoto

2011-03-01

In this report, an overview of the recent status of photovoltaic (PV) power generation is first presented from the viewpoint of reducing CO2 emission. Next, the Japanese roadmap for the research and development (R&D) of PV power generation and the progress in the development of various solar cells are explained. In addition, the present status and future prospects of amorphous silicon (a-Si) thin-film solar cells, which are expected to enter the stage of full-scale practical application in the near future, are described. For a-Si single-junction solar cells, the conversion efficiency of their large-area modules has now reached 6-8%, and their practical application to megawatt solar systems has started. Meanwhile, the focus of R&D has been shifting to a-Si and microcrystalline silicon (µc-Si) tandem solar cells. Thus far, a-Si/µc-Si tandem solar cell modules with conversion efficiency exceeding 13% have been reported. In addition, triple-junction solar cells, whose target year for practical application is 2025 or later, are introduced, as well as innovative thin-film full-spectrum solar cells, whose target year of realization is 2050.

Apparatus for mounting photovoltaic power generating systems on buildings

DOEpatents

Russell, Miles C [Lincoln, MA

2009-08-18

Rectangular photovoltaic (PV) modules are mounted on a building roof by mounting stands that are distributed in rows and columns. Each stand comprises a base plate and first and second different height brackets attached to opposite ends of the base plate. Each first and second bracket comprises two module-support members. One end of each module is pivotally attached to and supported by a first module-support member of a first bracket and a second module-support member of another first bracket. At its other end each module rests on but is connected by flexible tethers to module-support members of two different second brackets. The tethers are sized to allow the modules to pivot up away from the module-support members on which they rest to a substantially horizontal position in response to wind uplift forces.

Analysis of mismatch and shading effects in a photovoltaic array using different technologies

NASA Astrophysics Data System (ADS)

Guerrero, J.; Muñoz, Y.; Ibáñez, F.; Ospino, A.

2014-06-01

In this paper, we analyze the performance of a photovoltaic array implemented in the Universidad Politécnica de Valencia which consists of modules of different technologies and power, connected in series, in order to quantify the energy losses due to mismatch and the effect of the shadows. To do this, the performance of the modules was measured in operation under ambient conditions with field measurement equipment (AMPROBE Solar Analyzer, Solar - 4000), which allows the extrapolation of measures to standard conditions STC. For the data validation, measures under controlled conditions were taken to some modules in the flash test laboratory of the Institute of Energy Technology ITE of Valencia in Spain. Subsequently the array curves measured were validated with a photovoltaic array model developed in MATLAB-Simulink for the same conditions and technologies. The results of this particular array are lost up to 20% of the energy supplied due to the modules mismatch. The study shows the curves and the energy loss due to shadows modules. This result opens scenarios for conceivable modifications to the PV field configurations today, chosen during the design stage and unchangeable during the operating stage; and gives greater importance to the energy loss by mismatch in the PV array.

Module 1: Text Versions | State, Local, and Tribal Governments | NREL

Science.gov Websites

bonus module is on using solar PV for resilience. And, as Jenny and Harrison both mentioned, if you do working definition. To simply resilience and to incorporate solutions like on-site solar PV, NREL has into solar PV projects. Energy resilience can only be achieved by understanding energy needs and

Design and economics of a photovoltaic concentrator array for off-grid applications

NASA Astrophysics Data System (ADS)

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

1982-09-01

The array design and expected operation of a photovoltaic concentrator are discussed. A second generation stand alone 680 W/sub p/ photovoltaic (PV) concentrating array for low power, nongrid connected applications was designed. The array consists of six passive cooled point focus Fresnel lens concentrating modules on a two axis polar mount tracking structure. The new array design incorporates several major improvements to the first generation design. These include 50% more array area and a control system which allows unattended, fully automatic operation. The life cycle energy costs are calculated and compared to the equivalent energy costs of a 3 kW diesel electric generator set and an equivalent flat panel PV system.

Solar Energy for Rural Egypt

NASA Astrophysics Data System (ADS)

Abdelsalam, Tarek I.; Darwish, Ziad; Hatem, Tarek M.

Egypt is currently experiencing the symptoms of an energy crisis, such as electricity outage and high deficit, due to increasing rates of fossil fuels consumption. Conversely, Egypt has a high solar availability of more than 18.5 MJ daily. Additionally, Egypt has large uninhabited deserts on both sides of the Nile valley and Sinai Peninsula, which both represent more than 96.5 % of the nation's total land area. Therefore, solar energy is one of the promising solutions for the energy shortage in Egypt. Furthermore, these vast lands are advantageous for commissioning large-scaled solar power projects, not only in terms of space availability, but also of availability of high quality silicon (sand) required for manufacturing silicon wafers used in photovoltaic (PV) modules. Also, rural Egypt is considered market a gap for investors, due to low local competition, and numerous remote areas that are not connected to the national electricity grid. Nevertheless, there are some obstacles that hinder the progress of solar energy in Egypt; for instance, the lack of local manufacturing capabilities, security, and turbulent market in addition to other challenges. This paper exhibits an experience of the authors designing and installing decentralized PV solar systems, with a total rated power of about 11 kW, installed at two rural villages in at the suburbs of Fayoum city, in addition to a conceptual design of a utility scale, 2 MW, PV power plant to be installed in Kuraymat. The outcomes of this experience asserted that solar PV systems can be a more technically and economically feasible solution for the energy problem in rural villages.

Using PVFORM, a systems performance model, to determine optimum mounting configurations for flat-plate photovoltaic modules

NASA Astrophysics Data System (ADS)

Menicucci, D. F.

The performance of a photovoltaic (PV) system is affected by the particular mounting configuration selected. But the optimal configuration for various potential designs is unknown because too few PV systems have been fielded. Sandia National Laboratories (SNLA) is currently conducting a controlled field experiment in which four of the most commonly used module mounting configurations are being compared. The data from the experiment are used to verify the accuracy of PVFORM, a new PV performance model. The model is then used to simulate the performance of PV modules mounted in different configurations in eight sites throughtout the U.S. The module mounting configurations, the experimental methods used, the specialized statistical techniques used in the analysis and the final results of the effort are described. The module mounting configurations are rank ordered at each site according to their energy production performane and each is briefly discussed in terms of its advantages or disadvantages in various applications.

Solar simulators vs outdoor module performance in the Negev Desert

DOE Office of Scientific and Technical Information (OSTI.GOV)

Faiman, D

The power output of photovoltaic cells depends on the intensity of the incoming light, its spectral content and the cell temperature. In order to be able to predict the performance of a pv system, therefore, it is of paramount importance to be able to quantify cell performance in a reproducible manner. The standard laboratory technique for this purpose is to employ a solar simulator and a calibrated reference cell. Such a setup enables module performance to be assessed under constant, standard, illumination and temperature conditions. However, this technique has three inherent weaknesses.

A circuit-based photovoltaic module simulator with shadow and fault settings

NASA Astrophysics Data System (ADS)

Chao, Kuei-Hsiang; Chao, Yuan-Wei; Chen, Jyun-Ping

2016-03-01

The main purpose of this study was to develop a photovoltaic (PV) module simulator. The proposed simulator, using electrical parameters from solar cells, could simulate output characteristics not only during normal operational conditions, but also during conditions of partial shadow and fault conditions. Such a simulator should possess the advantages of low cost, small size and being easily realizable. Experiments have shown that results from a proposed PV simulator of this kind are very close to that from simulation software during partial shadow conditions, and with negligible differences during fault occurrence. Meanwhile, the PV module simulator, as developed, could be used on various types of series-parallel connections to form PV arrays, to conduct experiments on partial shadow and fault events occurring in some of the modules. Such experiments are designed to explore the impact of shadow and fault conditions on the output characteristics of the system as a whole.

Sensitivities of projected 1980 photovoltaic system costs to major system cost drivers

NASA Technical Reports Server (NTRS)

Zimmerman, L. W.; Smith, J. L.

1984-01-01

The sensitivity of projected 1990 photovoltaic (PV) system costs to major system cost drivers was examined. It includes: (1) module costs and module efficiencies; (2) area related balance of system (BOS) costs; (3) inverter costs and efficiencies; and (4) module marketing and distribution markups and system integration fees. Recent PV system cost experiences and the high costs of electricity from the systems are reviewed. The 1990 system costs are projected for five classes of PV systems, including four ground mounted 5-MWp systems and one residential 5-kWp system. System cost projections are derived by first projecting costs and efficiencies for all subsystems and components. Sensitivity analyses reveal that reductions in module cost and engineering and system integration fees seem to have the greatest potential for contributing to system cost reduction. Although module cost is clearly the prime candidate for fruitful PV research and development activities, engineering and system integration fees seem to be more amenable to reduction through appropriate choice of system size and market strategy. Increases in inverter and module efficiency yield significant benefits, especially for systems with high area related costs.

NREL Photovoltaic Program. FY 1994 annual report, October 1, 1993--September 30, 1994

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1995-06-01

This report summarizes the in-house and subcontracted research and development activities under the National renewable Energy Laboratory (NREL) Photovoltaics (PV) program for fiscal year 1994. Research is organized under the following areas; PV program management; crystalline silicon and advanced devices; thin-film PV technologies; PV manufacturing; PV module and system performance and engineering; and PV applications and markets.

Singing modulates parvalbumin interneurons throughout songbird forebrain vocal control circuitry

PubMed Central

Zengin-Toktas, Yildiz

2017-01-01

Across species, the performance of vocal signals can be modulated by the social environment. Zebra finches, for example, adjust their song performance when singing to females (‘female-directed’ or FD song) compared to when singing in isolation (‘undirected’ or UD song). These changes are salient, as females prefer the FD song over the UD song. Despite the importance of these performance changes, the neural mechanisms underlying this social modulation remain poorly understood. Previous work in finches has established that expression of the immediate early gene EGR1 is increased during singing and modulated by social context within the vocal control circuitry. Here, we examined whether particular neural subpopulations within those vocal control regions exhibit similar modulations of EGR1 expression. We compared EGR1 expression in neurons expressing parvalbumin (PV), a calcium buffer that modulates network plasticity and homeostasis, among males that performed FD song, males that produced UD song, or males that did not sing. We found that, overall, singing but not social context significantly affected EGR1 expression in PV neurons throughout the vocal control nuclei. We observed differences in EGR1 expression between two classes of PV interneurons in the basal ganglia nucleus Area X. Additionally, we found that singing altered the amount of PV expression in neurons in HVC and Area X and that distinct PV interneuron types in Area X exhibited different patterns of modulation by singing. These data indicate that throughout the vocal control circuitry the singing-related regulation of EGR1 expression in PV neurons may be less influenced by social context than in other neuron types and raise the possibility of cell-type specific differences in plasticity and calcium buffering. PMID:28235074

NREL to Host Ninth Annual PV Reliability Workshop | News | NREL

Science.gov Websites

share research leading to more durable and reliable PV modules, thus reducing the cost of solar to Host Ninth Annual PV Reliability Workshop NREL to Host Ninth Annual PV Reliability Workshop their results during a poster session at the 2017 PV Reliability Workshop. 4 people consult two

Emerging photovoltaic technologies: Environmental and health issues update

NASA Astrophysics Data System (ADS)

Fthenakis, Vasilis M.; Moskowitz, Paul D.

1997-02-01

New photovoltaic (PV) technologies promise low-cost, reliable PV modules and have the potential for significant PV penetration into the energy market. These prospects for commercialization have attracted renewed interest in the advantageous environmental impact of using PV and also in the potential environmental, health and safety (EHS) burdens in PV manufacturing and decommissioning. In this paper, we highlight recent studies on EHS issues: a) An integrated energy-environmental-economic analysis which shows that large-scale use of PV can significantly contribute to alleviating the greenhouse effect; in the United States alone, it could displace 450 million tons of carbon emissions by the year 2030, b) Recycling of the spent modules and scarp is economically feasible; current research centers on improving the efficiency and economics of recycling CdTe and CIS modules, c) Toxicological studies conducted by the National Institute of Environmental Health Sciences (NIEHS) compared the acute toxicity of CdTe, CIS, and CGS; CdTe was the most toxic, and CGS the least toxic of the three. Additional studies are now comparing the systemic toxicity of these compounds with the toxicity of their precursors.

Enhanced power quality based single phase photovoltaic distributed generation system

NASA Astrophysics Data System (ADS)

Panda, Aurobinda; Pathak, M. K.; Srivastava, S. P.

2016-08-01

This article presents a novel control strategy for a 1-ϕ 2-level grid-tie photovoltaic (PV) inverter to enhance the power quality (PQ) of a PV distributed generation (PVDG) system. The objective is to obtain the maximum benefits from the grid-tie PV inverter by introducing current harmonics as well as reactive power compensation schemes in its control strategy, thereby controlling the PV inverter to achieve multiple functions in the PVDG system such as: (1) active power flow control between the PV inverter and the grid, (2) reactive power compensation, and (3) grid current harmonics compensation. A PQ enhancement controller (PQEC) has been designed to achieve the aforementioned objectives. The issue of underutilisation of the PV inverter in nighttime has also been addressed in this article and for the optimal use of the system; the PV inverter is used as a shunt active power filter in nighttime. A prototype model of the proposed system is developed in the laboratory, to validate the effectiveness of the control scheme, and is tested with the help of the dSPACE DS1104 platform.

An Operating Method Using Prediction of Photovoltaic Power for a Photovoltaic-Diesel Hybrid Power Generation System

NASA Astrophysics Data System (ADS)

Yamamoto, Shigehiro; Sumi, Kazuyoshi; Nishikawa, Eiichi; Hashimoto, Takeshi

This paper describes a novel operating method using prediction of photovoltaic (PV) power for a photovoltaic-diesel hybrid power generation system. The system is composed of a PV array, a storage battery, a bi-directional inverter and a diesel engine generator (DG). The proposed method enables the system to save fuel consumption by using PV energy effectively, reducing charge and discharge energy of the storage battery, and avoiding low-load operation of the DG. The PV power is simply predicted from a theoretical equation of solar radiation and the observed PV energy for a constant time before the prediction. The amount of fuel consumption of the proposed method is compared with that of other methods by a simulation based on measurement data of the PV power at an actual PV generation system for one year. The simulation results indicate that the amount of fuel consumption of the proposed method is smaller than that of any other methods, and is close to that of the ideal operation of the DG.

Feasibility Study on High Concentrating Photovoltaic Power Towers

NASA Astrophysics Data System (ADS)

Frohberger, Dirk; Jaus, Joachim; Wiesenfarth, Maike; Schramek, Philipp; Bett, Andreas W.

2010-10-01

This paper presents an analysis on the concept of high concentrating PV power towers. A feasibility study is conducted in order to evaluate the future potential of this technology. Objective of the analysis is to provide an improved basis for establishing research and development priorities for the PV power tower concept. Performance assessments and cost calculations for a 1 MW prototype PV tower power are derived. Based on the assumption of a highly homogeneously illuminated receiver, levelized costs of electricity of 0.29 €/kWh have been calculated for a prototype PV tower power.

Photovoltaics: Energy for the New Millenium

NASA Astrophysics Data System (ADS)

Surek, Thomas

2000-04-01

Photovoltaics (PV) is a semiconductor-based technology that directly converts sunlight to electricity. The stimulus for terrestrial PV started more than 25 years ago in response to the oil crises of the 1970s, which resulted in major government programs in the United States, Europe, Japan, and elsewhere. Ongoing concerns with the global environment, as well as the worldwide efforts to seek alternate, indigenous sources of energy, continue to drive the investment in PV research and deployment. Today, the manufacture, sale, and use of PV has become a billion-dollar industry worldwide, with nearly 200 megawatts (MW) of PV modules shipped in 1999. The twenty five years of research and development led to the discovery of new PV materials, devices, and fabrication approaches; continuing improvements in the efficiency and reliability of solar cells and modules; and lower PV module and system costs. This talk reviews the rapid progress that has occurred in PV technology from the laboratory to the marketplace, including reviews of the leading technology options, status and issues, and key industry players. New processes for fabricating PV materials and devices, and innovative PV approaches with low-cost potential are elements of an ongoing research program aimed at future advancements in PV cost and performance While major market opportunities continue to exist in the developing countries, where sizable populations are without any electricity, today's manufacturing expansions are fueled by market initiatives for grid-connected PV in residential and commercial buildings. The combinations of increased production capacities, with the attendant cost reductions as a result of economies of scale, are expected to lead to sustainable markets. A key to achieving the ultimate potential of PV is to continue to increase the sunlight-to-electricity conversion efficiencies and translate the laboratory successes to cost-competitive products. Building a robust technology base is essential to overcoming this high-risk transition. Then PV will make a globally significant contribution to our energy supply and environment.

2017 NREL Photovoltaic Reliability Workshop

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, Sarah

NREL's Photovoltaic (PV) Reliability Workshop (PVRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology -- both critical goals for moving PV technologies deeper into the electricity marketplace.

In-situ comparison of thermal measurement technologies for interpretation of PV module temperature de-rating effects

NASA Astrophysics Data System (ADS)

Elwood, Teri; Bennett, Whit; Lai, Teh; Simmons-Potter, Kelly

2016-09-01

It is well known that the efficiency of a photovoltaic (PV) module is strongly impacted by its temperature such that higher temperatures lead to lower energy conversion efficiencies. An accurate measurement of the temperature de-rating effect, therefore, is vital to the correct interpretation of PV module performance under varied environmental conditions. The current work investigates and compares methods for performing measurements of module temperature both in the lab and in field-test environments. A comparison of several temperature measurement devices was made in order to establish the ideal sensor configuration for quantifying module operating temperature. Sensors were also placed in various locations along a string of up to eight photovoltaic modules to examine the variance in operating temperature with position in the string and within a larger array of strings.

Comparison of modeled and experimental PV array temperature profiles for accurate interpretation of module performance and degradation

NASA Astrophysics Data System (ADS)

Elwood, Teri; Simmons-Potter, Kelly

2017-08-01

Quantification of the effect of temperature on photovoltaic (PV) module efficiency is vital to the correct interpretation of PV module performance under varied environmental conditions. However, previous work has demonstrated that PV module arrays in the field are subject to significant location-based temperature variations associated with, for example, local heating/cooling and array edge effects. Such thermal non-uniformity can potentially lead to under-prediction or over-prediction of PV array performance due to an incorrect interpretation of individual module temperature de-rating. In the current work, a simulated method for modeling the thermal profile of an extended PV array has been investigated through extensive computational modeling utilizing ANSYS, a high-performance computational fluid dynamics (CFD) software tool. Using the local wind speed as an input, simulations were run to determine the velocity at particular points along modular strings corresponding to the locations of temperature sensors along strings in the field. The point velocities were utilized along with laminar flow theories in order to calculate Nusselt's number for each point. These calculations produced a heat flux profile which, when combined with local thermal and solar radiation profiles, were used as inputs in an ANSYS Thermal Transient model that generated a solar string operating temperature profile. A comparison of the data collected during field testing, and the data fabricated by ANSYS simulations, will be discussed in order to authenticate the accuracy of the model.

Market assessment of photovoltaic power systems for agricultural applications in Mexico

NASA Technical Reports Server (NTRS)

Steigelmann, W.; Asmon, I.

1981-01-01

The first year of cost-competitiveness, the market potential, and the environment in which PV systems would be marketed and employed were examined. Market elements specific to Mexico addressed include: (1) useful applications and estimates of the potential market for PV systems; (2) power requirements and load profiles for applications compatible with PV usage; (3) operating and cost characteristics of power systems that compete against PV; (4) national development goals in rural electrification and rural services, technology programs and government policies that influence the demand for PV in Mexico; (5) financing mechanisms and capital available for PV acquisition; (6) channels for distribution, installation and maintenance of PV systems; and (7) appropriate methods for conducting business in Mexico.

Market assessment of photovoltaic power systems for agricultural applications in Mexico

NASA Astrophysics Data System (ADS)

Steigelmann, W.; Asmon, I.

1981-07-01

The first year of cost-competitiveness, the market potential, and the environment in which PV systems would be marketed and employed were examined. Market elements specific to Mexico addressed include: (1) useful applications and estimates of the potential market for PV systems; (2) power requirements and load profiles for applications compatible with PV usage; (3) operating and cost characteristics of power systems that compete against PV; (4) national development goals in rural electrification and rural services, technology programs and government policies that influence the demand for PV in Mexico; (5) financing mechanisms and capital available for PV acquisition; (6) channels for distribution, installation and maintenance of PV systems; and (7) appropriate methods for conducting business in Mexico.

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

NASA Astrophysics Data System (ADS)

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.

Conjunction of Photovoltaic and Thermophotovoltaic Power Production in Spacecraft Power Systems

DTIC Science & Technology

2015-09-01

photovoltaic ( PV ) arrays, which draw electrical energy from the most prominent power source in our solar system, the Sun. These arrays are large, and pose...freemaps/1000px/dni/SolarGIS- Solar -map-DNI-World- map-en.png By contrast, spacecraft PV power production systems are not so limited. With the...operating parameters for a given solar cell, and PMax is generally the described Pout from which the PV cell’s efficiency is calculated. A PV cell’s

Estimating rooftop solar technical potential across the US using a combination of GIS-based methods, lidar data, and statistical modeling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gagnon, Pieter; Margolis, Robert; Melius, Jennifer

We provide a detailed estimate of the technical potential of rooftop solar photovoltaic (PV) electricity generation throughout the contiguous United States. This national estimate is based on an analysis of select US cities that combines light detection and ranging (lidar) data with a validated analytical method for determining rooftop PV suitability employing geographic information systems. We use statistical models to extend this analysis to estimate the quantity and characteristics of roofs in areas not covered by lidar data. Finally, we model PV generation for all rooftops to yield technical potential estimates. At the national level, 8.13 billion m 2 ofmore » suitable roof area could host 1118 GW of PV capacity, generating 1432 TWh of electricity per year. This would equate to 38.6% of the electricity that was sold in the contiguous United States in 2013. This estimate is substantially higher than a previous estimate made by the National Renewable Energy Laboratory. The difference can be attributed to increases in PV module power density, improved estimation of building suitability, higher estimates of total number of buildings, and improvements in PV performance simulation tools that previously tended to underestimate productivity. Also notable, the nationwide percentage of buildings suitable for at least some PV deployment is high—82% for buildings smaller than 5000 ft 2 and over 99% for buildings larger than that. In most states, rooftop PV could enable small, mostly residential buildings to offset the majority of average household electricity consumption. Even in some states with a relatively poor solar resource, such as those in the Northeast, the residential sector has the potential to offset around 100% of its total electricity consumption with rooftop PV.« less

Estimating rooftop solar technical potential across the US using a combination of GIS-based methods, lidar data, and statistical modeling

DOE PAGES

Gagnon, Pieter; Margolis, Robert; Melius, Jennifer; ...

2018-01-05

We provide a detailed estimate of the technical potential of rooftop solar photovoltaic (PV) electricity generation throughout the contiguous United States. This national estimate is based on an analysis of select US cities that combines light detection and ranging (lidar) data with a validated analytical method for determining rooftop PV suitability employing geographic information systems. We use statistical models to extend this analysis to estimate the quantity and characteristics of roofs in areas not covered by lidar data. Finally, we model PV generation for all rooftops to yield technical potential estimates. At the national level, 8.13 billion m 2 ofmore » suitable roof area could host 1118 GW of PV capacity, generating 1432 TWh of electricity per year. This would equate to 38.6% of the electricity that was sold in the contiguous United States in 2013. This estimate is substantially higher than a previous estimate made by the National Renewable Energy Laboratory. The difference can be attributed to increases in PV module power density, improved estimation of building suitability, higher estimates of total number of buildings, and improvements in PV performance simulation tools that previously tended to underestimate productivity. Also notable, the nationwide percentage of buildings suitable for at least some PV deployment is high—82% for buildings smaller than 5000 ft 2 and over 99% for buildings larger than that. In most states, rooftop PV could enable small, mostly residential buildings to offset the majority of average household electricity consumption. Even in some states with a relatively poor solar resource, such as those in the Northeast, the residential sector has the potential to offset around 100% of its total electricity consumption with rooftop PV.« less

Estimating rooftop solar technical potential across the US using a combination of GIS-based methods, lidar data, and statistical modeling

NASA Astrophysics Data System (ADS)

Gagnon, Pieter; Margolis, Robert; Melius, Jennifer; Phillips, Caleb; Elmore, Ryan

2018-02-01

We provide a detailed estimate of the technical potential of rooftop solar photovoltaic (PV) electricity generation throughout the contiguous United States. This national estimate is based on an analysis of select US cities that combines light detection and ranging (lidar) data with a validated analytical method for determining rooftop PV suitability employing geographic information systems. We use statistical models to extend this analysis to estimate the quantity and characteristics of roofs in areas not covered by lidar data. Finally, we model PV generation for all rooftops to yield technical potential estimates. At the national level, 8.13 billion m2 of suitable roof area could host 1118 GW of PV capacity, generating 1432 TWh of electricity per year. This would equate to 38.6% of the electricity that was sold in the contiguous United States in 2013. This estimate is substantially higher than a previous estimate made by the National Renewable Energy Laboratory. The difference can be attributed to increases in PV module power density, improved estimation of building suitability, higher estimates of total number of buildings, and improvements in PV performance simulation tools that previously tended to underestimate productivity. Also notable, the nationwide percentage of buildings suitable for at least some PV deployment is high—82% for buildings smaller than 5000 ft2 and over 99% for buildings larger than that. In most states, rooftop PV could enable small, mostly residential buildings to offset the majority of average household electricity consumption. Even in some states with a relatively poor solar resource, such as those in the Northeast, the residential sector has the potential to offset around 100% of its total electricity consumption with rooftop PV.

When PV modules are becoming real building elements: White solar module, a revolution for BIPV (Presentation Recording)

NASA Astrophysics Data System (ADS)

Perret-Aebi, Laure-Emmanuelle; Escarré, Jordi; Li, Heng-Yu; Sansonnens, Laurent; Galliano, Federico; Cattaneo, Gianluca; Heinstein, Patrick; Nicolay, Sylvain; Bailat, Julien; Eberhard, Sébastien; Ballif, Christophe

2015-09-01

The use of photovoltaic (PV) is not anymore an option but a real need in the construction of nearly zero energy buildings. To date, the lack of PV products specifically designed for building integration, considering aesthetics and architectural aspects, is one important limiting factor allowing a massive deployment of PV in the built environment. Architects are continuously asking for new solutions to customize the colour of PV elements to better integrate them into the building skin. Among these colours, white is especially attractive as it is widely used in architecture for its elegance, versatility and fresh look. Until now, white solar modules were not considered to be an option and even never been though to be a technological possibility. Nonetheless, CSEM recently developed a new technology to make white solar modules a reality. Furthermore, the new Swiss company called Solaxess is now working on the industrialisation of this very innovative technology and the first products are expecting to be on the market at the end of 2015. The technology is based on the combination of two different elements: a solar cell able to convert solar infrared light into electricity and a selective filter which reflects and diffuse the whole visible spectrum. Any PV technology based on crystalline silicon can be used as they have a good response in the infrared. Approximately 55% of the current generated under standard test conditions comes from the infrared leading to conversion efficiencies above 11%. We will demonstrate, that thanks to this very innovative technology PV modules can become attractive and real active building elements and therefore meets the requirements of any future energy management through advanced building skins.

Photovoltaic Reliability Group activities in USA and Brazil (Presentation Recording)

NASA Astrophysics Data System (ADS)

Dhere, Neelkanth G.; Cruz, Leila R. O.

2015-09-01

Recently prices of photovoltaic (PV) systems have been reduced considerably and may continue to be reduced making them attractive. If these systems provide electricity over the stipulated warranty period, it would be possible attain socket parity within the next few years. Current photovoltaic module qualifications tests help in minimizing infant mortality but do not guarantee useful lifetime over the warranty period. The PV Module Quality Assurance Task Force (PVQAT) is trying to formulate accelerated tests that will be useful towards achieving the ultimate goal of assuring useful lifetime over the warranty period as well as to assure manufacturing quality. Unfortunately, assuring the manufacturing quality may require 24/7 presence. Alternatively, collecting data on the performance of fielded systems would assist in assuring manufacturing quality. Here PV systems installed by home-owners and small businesses can constitute as an important untapped source of data. The volunteer group, PV - Reliable, Safe and Sustainable Quality! (PVRessQ!) is providing valuable service to small PV system owners. Photovoltaic Reliability Group (PVRG) is initiating activities in USA and Brazil to assist home owners and small businesses in monitoring photovoltaic (PV) module performance and enforcing warranty. It will work in collaboration with small PV system owners, consumer protection agencies. Brazil is endowed with excellent solar irradiance making it attractive for installation of PV systems. Participating owners of small PV systems would instruct inverter manufacturers to copy the daily e-mails to PVRG and as necessary, will authorize the PVRG to carry out review of PV systems. The presentation will consist of overall activities of PVRG in USA and Brazil.

Improvements in world-wide intercomparison of PV module calibration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Salis, E.; Pavanello, D.; Field, M.

The calibration of the electrical performance of seven photovoltaic (PV) modules was compared between four reference laboratories on three continents. The devices included two samples in standard and two in high-efficiency crystalline silicon technology, two CI(G)S and one CdTe module. The reference value for each PV module parameter was calculated from the average of the results of all four laboratories, weighted by the respective measurement uncertainties. All single results were then analysed with respect to this reference value using the E n number approach. For the four modules in crystalline silicon technology, the results agreed in general within +/-0.5%, withmore » all values within +/-1% and all E n numbers well within [-1, 1], indicating further scope for reducing quoted measurement uncertainty. Regarding the three thin-film modules, deviations were on average roughly twice as large, i.e. in general from +/-1% to +/-2%. A number of inconsistent results were observable, although within the 5% that can be statistically expected on the basis of the E n number approach. Most inconsistencies can be traced to the preconditioning procedure of one participant, although contribution of other factors cannot be ruled out. After removing these obvious inconsistent results, only two real outliers remained, representing less than 2% of the total number of measurands. The results presented show improved agreement for the calibration of PV modules with respect to previous international exercises. For thin-film PV modules, the preconditioning of the devices prior to calibration measurements is the most critical factor for obtaining consistent results, while the measurement processes seem consistent and repeatable.« less

Improvements in world-wide intercomparison of PV module calibration

DOE PAGES

Salis, E.; Pavanello, D.; Field, M.; ...

2017-09-14

The calibration of the electrical performance of seven photovoltaic (PV) modules was compared between four reference laboratories on three continents. The devices included two samples in standard and two in high-efficiency crystalline silicon technology, two CI(G)S and one CdTe module. The reference value for each PV module parameter was calculated from the average of the results of all four laboratories, weighted by the respective measurement uncertainties. All single results were then analysed with respect to this reference value using the E n number approach. For the four modules in crystalline silicon technology, the results agreed in general within +/-0.5%, withmore » all values within +/-1% and all E n numbers well within [-1, 1], indicating further scope for reducing quoted measurement uncertainty. Regarding the three thin-film modules, deviations were on average roughly twice as large, i.e. in general from +/-1% to +/-2%. A number of inconsistent results were observable, although within the 5% that can be statistically expected on the basis of the E n number approach. Most inconsistencies can be traced to the preconditioning procedure of one participant, although contribution of other factors cannot be ruled out. After removing these obvious inconsistent results, only two real outliers remained, representing less than 2% of the total number of measurands. The results presented show improved agreement for the calibration of PV modules with respect to previous international exercises. For thin-film PV modules, the preconditioning of the devices prior to calibration measurements is the most critical factor for obtaining consistent results, while the measurement processes seem consistent and repeatable.« less

Concentrated solar power plants impact on PV penetration level and grid flexibility under Egyptian climate

NASA Astrophysics Data System (ADS)

Moukhtar, Ibrahim; Elbaset, Adel A.; El Dein, Adel Z.; Qudaih, Yaser; Mitani, Yasunori

2018-05-01

Photovoltaic (PV) system integration in the electric grid has been increasing over the past decades. However, the impact of PV penetration on the electric grid, especially during the periods of higher and lower generation for the solar system at the middle of the day and during cloudy weather or at night respectively, limit the high penetration of solar PV system. In this research, a Concentrated Solar Power (CSP) with Thermal Energy Storage (TES) has been aggregated with PV system in order to accommodate the required electrical power during the higher and lower solar energy at all timescales. This paper analyzes the impacts of CSP on the grid-connected PV considering high penetration of PV system, particularly when no energy storages in the form of batteries are used. Two cases have been studied, the first when only PV system is integrated into the electric grid and the second when two types of solar energy (PV and CSP) are integrated. The System Advisor Model (SAM) software is used to simulate the output power of renewable energy. Simulation results show that the performance of CSP has a great impact on the penetration level of PV system and on the flexibility of the electric grid. The overall grid flexibility increases due to the ability of CSP to store and dispatch the generated power. In addition, CSP/TES itself has inherent flexibility. Therefore, CSP reduces the minimum generation constraint of the conventional generators that allows more penetration of the PV system.

Thin-film photovoltaic power generation offers decreasing greenhouse gas emissions and increasing environmental co-benefits in the long term.

PubMed

Bergesen, Joseph D; Heath, Garvin A; Gibon, Thomas; Suh, Sangwon

2014-08-19

Thin-film photovoltaic (PV) technologies have improved significantly recently, and similar improvements are projected into the future, warranting reevaluation of the environmental implications of PV to update and inform policy decisions. By conducting a hybrid life cycle assessment using the most recent manufacturing data and technology roadmaps, we compare present and projected environmental, human health, and natural resource implications of electricity generated from two common thin-film PV technologies-copper indium gallium selenide (CIGS) and cadmium telluride (CdTe)-in the United States (U.S.) to those of the current U.S. electricity mix. We evaluate how the impacts of thin films can be reduced by likely cost-reducing technological changes: (1) module efficiency increases, (2) module dematerialization, (3) changes in upstream energy and materials production, and (4) end-of-life recycling of balance of system (BOS). Results show comparable environmental and resource impacts for CdTe and CIGS. Compared to the U.S. electricity mix in 2010, both perform at least 90% better in 7 of 12 and at least 50% better in 3 of 12 impact categories, with comparable land use, and increased metal depletion unless BOS recycling is ensured. Technological changes, particularly efficiency increases, contribute to 35-80% reductions in all impacts by 2030.

Random Forest-Based Approach for Maximum Power Point Tracking of Photovoltaic Systems Operating under Actual Environmental Conditions.

PubMed

Shareef, Hussain; Mutlag, Ammar Hussein; Mohamed, Azah

2017-01-01

Many maximum power point tracking (MPPT) algorithms have been developed in recent years to maximize the produced PV energy. These algorithms are not sufficiently robust because of fast-changing environmental conditions, efficiency, accuracy at steady-state value, and dynamics of the tracking algorithm. Thus, this paper proposes a new random forest (RF) model to improve MPPT performance. The RF model has the ability to capture the nonlinear association of patterns between predictors, such as irradiance and temperature, to determine accurate maximum power point. A RF-based tracker is designed for 25 SolarTIFSTF-120P6 PV modules, with the capacity of 3 kW peak using two high-speed sensors. For this purpose, a complete PV system is modeled using 300,000 data samples and simulated using the MATLAB/SIMULINK package. The proposed RF-based MPPT is then tested under actual environmental conditions for 24 days to validate the accuracy and dynamic response. The response of the RF-based MPPT model is also compared with that of the artificial neural network and adaptive neurofuzzy inference system algorithms for further validation. The results show that the proposed MPPT technique gives significant improvement compared with that of other techniques. In addition, the RF model passes the Bland-Altman test, with more than 95 percent acceptability.

Random Forest-Based Approach for Maximum Power Point Tracking of Photovoltaic Systems Operating under Actual Environmental Conditions

PubMed Central

Shareef, Hussain; Mohamed, Azah

2017-01-01

Many maximum power point tracking (MPPT) algorithms have been developed in recent years to maximize the produced PV energy. These algorithms are not sufficiently robust because of fast-changing environmental conditions, efficiency, accuracy at steady-state value, and dynamics of the tracking algorithm. Thus, this paper proposes a new random forest (RF) model to improve MPPT performance. The RF model has the ability to capture the nonlinear association of patterns between predictors, such as irradiance and temperature, to determine accurate maximum power point. A RF-based tracker is designed for 25 SolarTIFSTF-120P6 PV modules, with the capacity of 3 kW peak using two high-speed sensors. For this purpose, a complete PV system is modeled using 300,000 data samples and simulated using the MATLAB/SIMULINK package. The proposed RF-based MPPT is then tested under actual environmental conditions for 24 days to validate the accuracy and dynamic response. The response of the RF-based MPPT model is also compared with that of the artificial neural network and adaptive neurofuzzy inference system algorithms for further validation. The results show that the proposed MPPT technique gives significant improvement compared with that of other techniques. In addition, the RF model passes the Bland–Altman test, with more than 95 percent acceptability. PMID:28702051

Utilizing Maximum Power Point Trackers in Parallel to Maximize the Power Output of a Solar (Photovoltaic) Array

DTIC Science & Technology

2012-12-01

photovoltaic (PV) system to use a maximum power point tracker ( MPPT ) to increase... photovoltaic (PV) system to use a maximum power point tracker ( MPPT ) to increase the power output of the solar array. Currently, most military... MPPT ) is an optimizing circuit that is used in conjunction with photovoltaic (PV) arrays to achieve the maximum delivery of power from the array

Demonstration of Essential Reliability Services by a 300-MW Solar Photovoltaic Power Plant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Loutan, Clyde; Klauer, Peter; Chowdhury, Sirajul

The California Independent System Operator (CAISO), First Solar, and the National Renewable Energy Laboratory (NREL) conducted a demonstration project on a large utility-scale photovoltaic (PV) power plant in California to test its ability to provide essential ancillary services to the electric grid. With increasing shares of solar- and wind-generated energy on the electric grid, traditional generation resources equipped with automatic governor control (AGC) and automatic voltage regulation controls -- specifically, fossil thermal -- are being displaced. The deployment of utility-scale, grid-friendly PV power plants that incorporate advanced capabilities to support grid stability and reliability is essential for the large-scale integrationmore » of PV generation into the electric power grid, among other technical requirements. A typical PV power plant consists of multiple power electronic inverters and can contribute to grid stability and reliability through sophisticated 'grid-friendly' controls. In this way, PV power plants can be used to mitigate the impact of variability on the grid, a role typically reserved for conventional generators. In August 2016, testing was completed on First Solar's 300-MW PV power plant, and a large amount of test data was produced and analyzed that demonstrates the ability of PV power plants to use grid-friendly controls to provide essential reliability services. These data showed how the development of advanced power controls can enable PV to become a provider of a wide range of grid services, including spinning reserves, load following, voltage support, ramping, frequency response, variability smoothing, and frequency regulation to power quality. Specifically, the tests conducted included various forms of active power control such as AGC and frequency regulation; droop response; and reactive power, voltage, and power factor controls. This project demonstrated that advanced power electronics and solar generation can be controlled to contribute to system-wide reliability. It was shown that the First Solar plant can provide essential reliability services related to different forms of active and reactive power controls, including plant participation in AGC, primary frequency control, ramp rate control, and voltage regulation. For AGC participation in particular, by comparing the PV plant testing results to the typical performance of individual conventional technologies, we showed that regulation accuracy by the PV plant is 24-30 points better than fast gas turbine technologies. The plant's ability to provide volt-ampere reactive control during periods of extremely low power generation was demonstrated as well. The project team developed a pioneering demonstration concept and test plan to show how various types of active and reactive power controls can leverage PV generation's value from being a simple variable energy resource to a resource that provides a wide range of ancillary services. With this project's approach to a holistic demonstration on an actual, large, utility-scale, operational PV power plant and dissemination of the obtained results, the team sought to close some gaps in perspectives that exist among various stakeholders in California and nationwide by providing real test data.« less

Plug and Play PV Systems for American Homes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hoepfner, Christian

2016-12-22

The core objectives of the Plug & Play PV Systems Project were to develop a PV system that can be installed on a residential rooftop for less than $1.50/W in 2020, and in less than 10 hours (from point of purchase to commissioning). The Fraunhofer CSE team’s approach to this challenge involved a holistic approach to system design – hardware and software – that make Plug & Play PV systems: • Quick, easy, and safe to install • Easy to demonstrate as code compliant • Permitted, inspected, and interconnected via an electronic process Throughout the three years of work duringmore » this Department of Energy SunShot funded project, the team engaged in a substantive way with inspectional services departments and utilities, manufacturers, installers, and distributors. We received iterative feedback on the system design and on ideas for how such systems can be commercialized. This ultimately led us to conceiving of Plug & Play PV Systems as a framework, with a variety of components compatible with the Plug & Play PV approach, including string or microinverters, conventional modules or emerging lightweight modules. The framework enables a broad group of manufacturers to participate in taking Plug & Play PV Systems to market, and increases the market size for such systems. Key aspects of the development effort centered on the system hardware and associated engineering work, the development of a Plug & Play PV Server to enable the electronic permitting, inspection and interconnection process, understanding the details of code compliance and, on occasion, supporting applications for modifications to the code to allow lightweight modules, for example. We have published a number of papers on our testing and assessment of novel technologies (e.g., adhered lightweight modules) and on the electronic architecture.« less

Energy 101: Solar PV

ScienceCinema

None

2018-01-08

Solar photovoltaic (PV) systems can generate clean, cost-effective power anywhere the sun shines. This video shows how a PV panel converts the energy of the sun into renewable electricity to power homes and businesses.

Description and status of NASA-LeRC/DOE photovoltaic applications systems

NASA Technical Reports Server (NTRS)

Ratajczak, A. F.

1978-01-01

Designed, fabricated and installed were 16 geographically dispersed photovoltaic systems. These systems are powering a refrigerator, highway warning sign, forest lookout towers, remote weather stations, a water chiller at a visitor center, and insect survey traps. Each of these systems is described in terms of load requirements, solar array and battery size, and instrumentation and controls. Operational experience is described and present status is given for each system. The P/V power systems have proven to be highly reliable with almost no problems with modules and very few problems overall.

The Capital Intensity of Photovoltaics Manufacturing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Basore, Paul

2015-10-19

Factory capital expenditure (capex) for photovoltaic (PV) module manufacturing strongly influences the per-unit cost of a c-Si module. This provides a significant opportunity to address the U.S. DOE SunShot module price target through capex innovation. Innovation options to reduce the capex of PV manufacturing include incremental and disruptive process innovation with c-Si, platform innovations, and financial approaches. and financial approaches.

Recent advances in the PV-CSP hybrid solar power technology

NASA Astrophysics Data System (ADS)

Ju, Xing; Xu, Chao; Han, Xue; Zhang, Hui; Wei, Gaosheng; Chen, Lin

2017-06-01

Photovoltaic - Concentrated Solar Power (PV-CSP) hybrid technology is considered to be an important future research trend in solar energy engineering. The development of the PV-CSP hybrid technology accelerates in recent years with the rapid maturation of photovoltaics (PV) and concentrated solar power (CSP). This paper presents the recent advances on PV-CSP technology, including different technologies based on new dispatch strategies, Organic Rankine Cycles, spectral beam filters and so on. The research status and the hybrid system performance of the recent researches are summarized, aimed to provide an extended recognition on the PV-CSP hybrid technology. The advantages and limitations of the hybrid system are concluded according to the researches reviewed.

A study on economic power dispatch grid connected PV power plant in educational institutes

NASA Astrophysics Data System (ADS)

Singh, Kuldip; Kumar, M. Narendra; Mishra, Satyasis

2018-04-01

India has main concerns on environment and escalation of fuel prices with respect to diminution of fossil fuel reserves and the major focus on renewable Energy sources for power generation to fulfill the present and future energy demand. Installation of PV power plants in the Educational Institutions has grown up drastically throughout India. More PV power plant are integrated with load and grid through net metering. Therefore, this paper is an analysis of the 75kWp PV plant at chosen buses, considering the need of minimum demand from the grid. The case study is carried out for different generation level throughout the day and year w.r.t load and climate changes, load sharing on grid. The economic dispatch model developed for PV plant integrated with Grid.

Distinct Thalamic Reticular Cell Types Differentially Modulate Normal and Pathological Cortical Rhythms.

PubMed

Clemente-Perez, Alexandra; Makinson, Stefanie Ritter; Higashikubo, Bryan; Brovarney, Scott; Cho, Frances S; Urry, Alexander; Holden, Stephanie S; Wimer, Matthew; Dávid, Csaba; Fenno, Lief E; Acsády, László; Deisseroth, Karl; Paz, Jeanne T

2017-06-06

Integrative brain functions depend on widely distributed, rhythmically coordinated computations. Through its long-ranging connections with cortex and most senses, the thalamus orchestrates the flow of cognitive and sensory information. Essential in this process, the nucleus reticularis thalami (nRT) gates different information streams through its extensive inhibition onto other thalamic nuclei, however, we lack an understanding of how different inhibitory neuron subpopulations in nRT function as gatekeepers. We dissociated the connectivity, physiology, and circuit functions of neurons within rodent nRT, based on parvalbumin (PV) and somatostatin (SOM) expression, and validated the existence of such populations in human nRT. We found that PV, but not SOM, cells are rhythmogenic, and that PV and SOM neurons are connected to and modulate distinct thalamocortical circuits. Notably, PV, but not SOM, neurons modulate somatosensory behavior and disrupt seizures. These results provide a conceptual framework for how nRT may gate incoming information to modulate brain-wide rhythms. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Chapter 10.3: Reliability and Durability of PV Modules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, Sarah

2017-01-07

Each year the world invests tens of billions of dollars or euros in PV systems with the expectation that these systems will last approximately 25 years. Although the disciplines of reliability, quality, and service life prediction have been well established for numerous products, a full understanding of these is currently challenging for PV modules because the desired service lifetimes are decades, preventing direct verification of lifetime predictions. A number of excellent reviews can be found in the literature summarizing the types of failures that are commonly observed for PV modules. This chapter discusses key failure/degradation mechanisms selected to highlight howmore » the kinetics of failure rates can and cannot be confidently predicted. For EVA-encapsulated modules, corrosion is observed to follow delamination, which then allows water droplets to directly contact the metallization. Extended test protocols such as Qualification Plus were created to address the known problems while standards groups update standard tests through the consensus process.« less

Photovoltaic Hosting Capacity of Feeders with Reactive Power Control and Tap Changers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ceylan, Oğuzhan; Paudyal, Sumit; Bhattarai, Bishnu P.

This paper proposes an algorithm to determine photovoltaic (PV) hosting capacity of power distribution networks as a function of number of PV injection nodes, reactive power support from the PVs, and the sub-station load tap changers (LTCs). In the proposed method, several minute by minute simulations are run based on randomly chosen PV injection nodes, daily PV output profiles, and daily load profiles from a pool of high-resolution realistic data set. The simulation setup is built using OpenDSS and MATLAB. The performance of the proposed method is investigated in the IEEE 123-node distribution feeder for multiple scenarios. The case studiesmore » are performed particularly for one, two, five and ten PV injection nodes, and looking at the maximum voltage deviations. Case studies show that the PV hosting capacity of the 123-node feeder greatly differs with the number of PV injection nodes. We have also observed that the PV hosting capacity increases with reactive power support and higher tap position of sub-station LTC.« less

U.S. Residential Photovoltaic (PV) System Prices, Q4 2013 Benchmarks: Cash Purchase, Fair Market Value, and Prepaid Lease Transaction Prices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davidson, C.; James, T. L.; Margolis, R.

The price of photovoltaic (PV) systems in the United States (i.e., the cost to the system owner) has dropped precipitously in recent years, led by substantial reductions in global PV module prices. This report provides a Q4 2013 update for residential PV systems, based on an objective methodology that closely approximates the book value of a PV system. Several cases are benchmarked to represent common variation in business models, labor rates, and module choice. We estimate a weighted-average cash purchase price of $3.29/W for modeled standard-efficiency, polycrystalline-silicon residential PV systems installed in the United States. This is a 46% declinemore » from the 2013-dollar-adjusted price reported in the Q4 2010 benchmark report. In addition, this report frames the cash purchase price in the context of key price metrics relevant to the continually evolving landscape of third-party-owned PV systems by benchmarking the minimum sustainable lease price and the fair market value of residential PV systems.« less

Experimental measurements of a prototype high-concentration Fresnel lens and sun-tracking method for photovoltaic panel's efficiency enhancement

NASA Astrophysics Data System (ADS)

Rajaee, Meraj; Ghorashi, Seyed Mohamad Bagher

2015-08-01

Concentrator photovoltaic modules are a promising technology for highly efficient solar energy conversion. This system presents several advantages due to additional degrees of freedom that has been provided by the spectral separation such as cost and mass reduction, increase in the incident solar flux on PV cells and performances. This paper has proposed a unique photovoltaic solar cell system that consists of semi-Fresnel lens convergent structure and a novel two axis sun tracking module to enhance the efficiency of solar cell by using less cell area and energy losses. The grooves of this lens are calculated according to the refraction and convergent angles of the light easy for perpendicular incidence angle. The update time interval during tracking causes misalignment of the lens' optical axis versus the sunrays. Then an inventive sun-tracking method is introduced to adjust the module so that the incident rays are always perpendicular to the module's surface. As a result, all rays will be refracted with the predetermined angles. This way the focus area is reduced and smaller cells can be used. We also mentioned different module connections in order to provide compensation method during losses, for networks and power systems. Experimental results show that using semi-Fresnel lens, along with the sun-tracking method increases the efficiency of PV panel.

Stochastic Short-term High-resolution Prediction of Solar Irradiance and Photovoltaic Power Output

DOE Office of Scientific and Technical Information (OSTI.GOV)

Melin, Alexander M.; Olama, Mohammed M.; Dong, Jin

The increased penetration of solar photovoltaic (PV) energy sources into electric grids has increased the need for accurate modeling and prediction of solar irradiance and power production. Existing modeling and prediction techniques focus on long-term low-resolution prediction over minutes to years. This paper examines the stochastic modeling and short-term high-resolution prediction of solar irradiance and PV power output. We propose a stochastic state-space model to characterize the behaviors of solar irradiance and PV power output. This prediction model is suitable for the development of optimal power controllers for PV sources. A filter-based expectation-maximization and Kalman filtering mechanism is employed tomore » estimate the parameters and states in the state-space model. The mechanism results in a finite dimensional filter which only uses the first and second order statistics. The structure of the scheme contributes to a direct prediction of the solar irradiance and PV power output without any linearization process or simplifying assumptions of the signal’s model. This enables the system to accurately predict small as well as large fluctuations of the solar signals. The mechanism is recursive allowing the solar irradiance and PV power to be predicted online from measurements. The mechanism is tested using solar irradiance and PV power measurement data collected locally in our lab.« less

Flexible packaging for PV modules

NASA Astrophysics Data System (ADS)

Dhere, Neelkanth G.

2008-08-01

Economic, flexible packages that provide needed level of protection to organic and some other PV cells over >25-years have not yet been developed. However, flexible packaging is essential in niche large-scale applications. Typical configuration used in flexible photovoltaic (PV) module packaging is transparent frontsheet/encapsulant/PV cells/flexible substrate. Besides flexibility of various components, the solder bonds should also be flexible and resistant to fatigue due to cyclic loading. Flexible front sheets should provide optical transparency, mechanical protection, scratch resistance, dielectric isolation, water resistance, UV stability and adhesion to encapsulant. Examples are Tefzel, Tedlar and Silicone. Dirt can get embedded in soft layers such as silicone and obscure light. Water vapor transmittance rate (WVTR) of polymer films used in the food packaging industry as moisture barriers are ~0.05 g/(m2.day) under ambient conditions. In comparison, light emitting diodes employ packaging components that have WVTR of ~10-6 g/(m2.day). WVTR of polymer sheets can be improved by coating them with dense inorganic/organic multilayers. Ethylene vinyl acetate, an amorphous copolymer used predominantly by the PV industry has very high O2 and H2O diffusivity. Quaternary carbon chains (such as acetate) in a polymer lead to cleavage and loss of adhesional strength at relatively low exposures. Reactivity of PV module components increases in presence of O2 and H2O. Adhesional strength degrades due to the breakdown of structure of polymer by reactive, free radicals formed by high-energy radiation. Free radical formation in polymers is reduced when the aromatic rings are attached at regular intervals. This paper will review flexible packaging for PV modules.

A review of manufacturing metrology for improved reliability of silicon photovoltaic modules

NASA Astrophysics Data System (ADS)

Davis, Kristopher O.; Walters, Joseph; Schneller, Eric; Seigneur, Hubert; Brooker, R. Paul; Scardera, Giuseppe; Rodgers, Marianne P.; Mohajeri, Nahid; Shiradkar, Narendra; Dhere, Neelkanth G.; Wohlgemuth, John; Rudack, Andrew C.; Schoenfeld, Winston V.

2014-10-01

In this work, the use of manufacturing metrology across the supply chain to improve crystalline silicon (c-Si) photovoltaic (PV) module reliability and durability is addressed. Additionally, an overview and summary of a recent extensive literature survey of relevant measurement techniques aimed at reducing or eliminating the probability of field failures is presented. An assessment of potential gaps is also given, wherein the PV community could benefit from new research and demonstration efforts. This review is divided into three primary areas representing different parts of the c-Si PV supply chain: (1) feedstock production, crystallization and wafering; (2) cell manufacturing; and (3) module manufacturing.

OUT Success Stories: Solar Roofing Shingles

DOE R&D Accomplishments Database

Johnson, N.

2000-08-01

Thin-film photovoltaic (PV) cells are now doubling as rooftop shingles. PV shingles offer many advantages. The energy generated from a building's PV rooftop shingles can provide power both to the building and the utility's power grid.

PV water pumping: NEOS Corporation recent PV water pumping activities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lane, C.

1995-11-01

NEOS Corporation has been very active in PV-powered water pumping, particularly with respect to electric utilities. Most of the recent activity has been through the Photovoltaic Services Network (PSN). The PSN is an independent, not-for-profit organization comprised of all types of electric utilities: rural electric coops, public power districts, investor-owned utilities, and power marketing agencies. The PSN`s mission is to work pro-actively to promote utility involvement in PV through education and training. PV information is distributed by the PSN in three primary forms: (1) consultation with PSN technical service representatives: (2) literature generated by the PSN; and (3) literature publishedmore » by other organizations. The PSN can also provide assistance to members in developing PV customer service programs. The PSN`s product support activities include consolidation of information on existing packaged PV systems and facilitation of the development of new PV product packages that meet utility-defined specifications for cost performance, and reliability. The PSN`s initial product support efforts will be focused on commercially available packaged PV systems for a variety of off-grid applications. In parallel with this effort, if no products exist that meet the PSN`s functional specifications, the PSN will initiate the second phase of product development support process by encouraging the development of new packaged systems. Through these services and product support activities, the PSN anticipates engaging all segments for the PV industry, thus providing benefits to PV systems suppliers as well as local PV service contractors.This paper describes field testing of pv power systems for water pumping.« less

Low concentration solar louvres for building integration

NASA Astrophysics Data System (ADS)

Vincenzi, D.; Aldegheri, F.; Baricordi, S.; Bernardoni, P.; Calabrese, G.; Guidi, V.; Pozzetti, L.

2013-09-01

The building integration of CPV modules offers several advantages over the integration of flat panel systems, but the decreasing price trend of standard modules observed in the last years has hampered the market expansion of CPV systems, which still don't rely on a low-cost mass production supply chain. To overcome this contingent issue and to foster the diffusion of innovative PV systems we developed a low concentration BIPV module with added functionalities, such as sunlight shading and building illumination. The electrical performances, retrieved under outdoor conditions, and the lighting performances of the Solar F-Light are shown. The latter indicate that it is suitable for ambient lighting, with a very limited power draw.

A new technique based on Artificial Bee Colony Algorithm for optimal sizing of stand-alone photovoltaic system.

PubMed

Mohamed, Ahmed F; Elarini, Mahdi M; Othman, Ahmed M

2014-05-01

One of the most recent optimization techniques applied to the optimal design of photovoltaic system to supply an isolated load demand is the Artificial Bee Colony Algorithm (ABC). The proposed methodology is applied to optimize the cost of the PV system including photovoltaic, a battery bank, a battery charger controller, and inverter. Two objective functions are proposed: the first one is the PV module output power which is to be maximized and the second one is the life cycle cost (LCC) which is to be minimized. The analysis is performed based on measured solar radiation and ambient temperature measured at Helwan city, Egypt. A comparison between ABC algorithm and Genetic Algorithm (GA) optimal results is done. Another location is selected which is Zagazig city to check the validity of ABC algorithm in any location. The ABC is more optimal than GA. The results encouraged the use of the PV systems to electrify the rural sites of Egypt.

A new technique based on Artificial Bee Colony Algorithm for optimal sizing of stand-alone photovoltaic system

PubMed Central

Mohamed, Ahmed F.; Elarini, Mahdi M.; Othman, Ahmed M.

2013-01-01

One of the most recent optimization techniques applied to the optimal design of photovoltaic system to supply an isolated load demand is the Artificial Bee Colony Algorithm (ABC). The proposed methodology is applied to optimize the cost of the PV system including photovoltaic, a battery bank, a battery charger controller, and inverter. Two objective functions are proposed: the first one is the PV module output power which is to be maximized and the second one is the life cycle cost (LCC) which is to be minimized. The analysis is performed based on measured solar radiation and ambient temperature measured at Helwan city, Egypt. A comparison between ABC algorithm and Genetic Algorithm (GA) optimal results is done. Another location is selected which is Zagazig city to check the validity of ABC algorithm in any location. The ABC is more optimal than GA. The results encouraged the use of the PV systems to electrify the rural sites of Egypt. PMID:25685507

A Study Examining Photovoltaic (PV) Solar Power as an Alternative for the Rebuilding of the Iraqi Electrical Power Generation Infrastructure

DTIC Science & Technology

2005-06-01

Logistics, BA-5590, BB- 390, BB-2590, PVPC, Iraq, Power Grid, Infrastructure, Cost Estimate, Photovoltaic Power Conversion (PVPC), MPPT 16. PRICE...the cost and feasibility of using photovoltaic (PV) solar power to assist in the rebuilding of the Iraqi electrical infrastructure. This project...cost and feasibility of using photovoltaic (PV) solar power to assist in the rebuilding of the Iraqi infrastructure. The project examines available

Diastolic chamber properties of the left ventricle assessed by global fitting of pressure-volume data: improving the gold standard of diastolic function.

PubMed

Bermejo, Javier; Yotti, Raquel; Pérez del Villar, Candelas; del Álamo, Juan C; Rodríguez-Pérez, Daniel; Martínez-Legazpi, Pablo; Benito, Yolanda; Antoranz, J Carlos; Desco, M Mar; González-Mansilla, Ana; Barrio, Alicia; Elízaga, Jaime; Fernández-Avilés, Francisco

2013-08-15

In cardiovascular research, relaxation and stiffness are calculated from pressure-volume (PV) curves by separately fitting the data during the isovolumic and end-diastolic phases (end-diastolic PV relationship), respectively. This method is limited because it assumes uncoupled active and passive properties during these phases, it penalizes statistical power, and it cannot account for elastic restoring forces. We aimed to improve this analysis by implementing a method based on global optimization of all PV diastolic data. In 1,000 Monte Carlo experiments, the optimization algorithm recovered entered parameters of diastolic properties below and above the equilibrium volume (intraclass correlation coefficients = 0.99). Inotropic modulation experiments in 26 pigs modified passive pressure generated by restoring forces due to changes in the operative and/or equilibrium volumes. Volume overload and coronary microembolization caused incomplete relaxation at end diastole (active pressure > 0.5 mmHg), rendering the end-diastolic PV relationship method ill-posed. In 28 patients undergoing PV cardiac catheterization, the new algorithm reduced the confidence intervals of stiffness parameters by one-fifth. The Jacobian matrix allowed visualizing the contribution of each property to instantaneous diastolic pressure on a per-patient basis. The algorithm allowed estimating stiffness from single-beat PV data (derivative of left ventricular pressure with respect to volume at end-diastolic volume intraclass correlation coefficient = 0.65, error = 0.07 ± 0.24 mmHg/ml). Thus, in clinical and preclinical research, global optimization algorithms provide the most complete, accurate, and reproducible assessment of global left ventricular diastolic chamber properties from PV data. Using global optimization, we were able to fully uncouple relaxation and passive PV curves for the first time in the intact heart.

Microsystem enabled photovoltaic modules and systems

DOEpatents

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.

Advanced Grid-Friendly Controls Demonstration for Utility-Scale

Science.gov Websites

PV power plant in CAISO's footprint. NREL, CAISO, and First Solar conducted demonstration tests that vendors, integrators, and utilities to develop and evaluate photovoltaic (PV) power plants with advanced grid-friendly capabilities. Graph of power over time that shows a PV plant varying output to follow an

An overview of photovoltaic applications in space

NASA Technical Reports Server (NTRS)

Wasel, Robert A.

1987-01-01

An overview is given of the uses of photovoltaic (PV) power in space. The contribution of PV systems on unmanned, low Earth orbit and inner planetary missions is noted. The development of PV technology along the two paths of high efficiency and high power is discussed. The importance of increasing the service life of PV systems is covered.

Southeast Regional Experiment Station

NASA Astrophysics Data System (ADS)

1994-08-01

This is the final report of the Southeast Regional Experiment Station project. The Florida Solar Energy Center (FSEC), a research institute of the University of Central Florida (UCF), has operated the Southeast Regional Experiment Station (SE RES) for the US Department of Energy (DOE) since September 1982. Sandia National Laboratories, Albuquerque (SNLA) provides technical program direction for both the SE RES and the Southwest Regional Experiment Station (SW RES) located at the Southwest Technology Development Institute at Las Cruces, New Mexico. This cooperative effort serves a critical role in the national photovoltaic program by conducting system evaluations, design assistance and technology transfer to enhance the cost-effective utilization and development of photovoltaic technology. Initially, the research focus of the SE RES program centered on utility-connected PV systems and associated issues. In 1987, the SE RES began evaluating amorphous silicon (a-Si) thin-film PV modules for application in utility-interactive systems. Stand-alone PV systems began receiving increased emphasis at the SE RES in 1986. Research projects were initiated that involved evaluation of vaccine refrigeration, water pumping and other stand-alone power systems. The results of this work have led to design optimization techniques and procedures for the sizing and modeling of PV water pumping systems. Later recent research at the SE RES included test and evaluation of batteries and charge controllers for stand-alone PV system applications. The SE RES project provided the foundation on which FSEC achieved national recognition for its expertise in PV systems research and related technology transfer programs. These synergistic products of the SE RES illustrate the high visibility and contributions the FSEC PV program offers to the DOE.

Emissions from photovoltaic life cycles.

PubMed

Fthenakis, Vasilis M; Kim, Hyung Chul; Alsema, Erik

2008-03-15

Photovoltaic (PV) technologies have shown remarkable progress recently in terms of annual production capacity and life cycle environmental performances, which necessitate timely updates of environmental indicators. Based on PV production data of 2004-2006, this study presents the life-cycle greenhouse gas emissions, criteria pollutant emissions, and heavy metal emissions from four types of major commercial PV systems: multicrystalline silicon, monocrystalline silicon, ribbon silicon, and thin-film cadmium telluride. Life-cycle emissions were determined by employing average electricity mixtures in Europe and the United States during the materials and module production for each PV system. Among the current vintage of PV technologies, thin-film cadmium telluride (CdTe) PV emits the least amount of harmful air emissions as it requires the least amount of energy during the module production. However, the differences in the emissions between different PV technologies are very small in comparison to the emissions from conventional energy technologies that PV could displace. As a part of prospective analysis, the effect of PV breeder was investigated. Overall, all PV technologies generate far less life-cycle air emissions per GWh than conventional fossil-fuel-based electricity generation technologies. At least 89% of air emissions associated with electricity generation could be prevented if electricity from photovoltaics displaces electricity from the grid.

Reliability and Engineering | Photovoltaic Research | NREL

Science.gov Websites

-Time PV and Solar Resource Testing We study long-term performance, reliability, and failures of PV (NCPV) at NREL, we focus on photovoltaic (PV) reliability research and development (R&D) to improve PV technologies. We test modules and systems for long-term performance and stress them in the field

Comparative Analysis of Reduced-Rule Compressed Fuzzy Logic Control and Incremental Conductance MPPT Methods

NASA Astrophysics Data System (ADS)

Kandemir, Ekrem; Borekci, Selim; Cetin, Numan S.

2018-04-01

Photovoltaic (PV) power generation has been widely used in recent years, with techniques for increasing the power efficiency representing one of the most important issues. The available maximum power of a PV panel is dependent on environmental conditions such as solar irradiance and temperature. To extract the maximum available power from a PV panel, various maximum-power-point tracking (MPPT) methods are used. In this work, two different MPPT methods were implemented for a 150-W PV panel. The first method, known as incremental conductance (Inc. Cond.) MPPT, determines the maximum power by measuring the derivative of the PV voltage and current. The other method is based on reduced-rule compressed fuzzy logic control (RR-FLC), using which it is relatively easier to determine the maximum power because a single input variable is used to reduce computing loads. In this study, a 150-W PV panel system model was realized using these MPPT methods in MATLAB and the results compared. According to the simulation results, the proposed RR-FLC-based MPPT could increase the response rate and tracking accuracy by 4.66% under standard test conditions.

Demonstration of Active Power Controls by Utility-Scale PV Power Plant in an Island Grid: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gevorgian, Vahan; O'Neill, Barbara

The National Renewable Energy Laboratory (NREL), AES, and the Puerto Rico Electric Power Authority conducted a demonstration project on a utility-scale photovoltaic (PV) plant to test the viability of providing important ancillary services from this facility. As solar generation increases globally, there is a need for innovation and increased operational flexibility. A typical PV power plant consists of multiple power electronic inverters and can contribute to grid stability and reliability through sophisticated 'grid-friendly' controls. In this way, it may mitigate the impact of its variability on the grid and contribute to important system requirements more like traditional generators. In 2015,more » testing was completed on a 20-MW AES plant in Puerto Rico, and a large amount of test data was produced and analyzed that demonstrates the ability of PV power plants to provide various types of new grid-friendly controls. This data showed how active power controls can leverage PV's value from being simply an intermittent energy resource to providing additional ancillary services for an isolated island grid. Specifically, the tests conducted included PV plant participation in automatic generation control, provision of droop response, and fast frequency response.« less

Earth abundant thin film technology for next generation photovoltaic modules

NASA Astrophysics Data System (ADS)

Alapatt, Githin Francis

With a cumulative generation capacity of over 100 GW, Photovoltaics (PV) technology is uniquely poised to become increasingly popular in the coming decades. Although, several breakthroughs have propelled PV technology, it accounts for only less than 1% of the energy produced worldwide. This aspect of the PV technology is primarily due to the somewhat high cost per watt, which is dependent on the efficiency of the PV cells as well as the cost of manufacturing and installing them. Currently, the efficiency of the PV conversion process is limited to about 25% for commercial terrestrial cells; improving this efficiency can increase the penetration of PV worldwide rapidly. A critical review of all possibilities pursued in the public domain reveals serious shortcomings and manufacturing issues. To make PV generated power a reality in every home, a Multi-Junction Multi-Terminal (MJMT) PV architecture can be employed combining silicon and another earth abundant material. However, forming electronic grade thin films of earth abundant materials is a non-trivial challenge; without solving this, it is impossible to increase the overall PV efficiency. Deposition of Copper (I) Oxide, an earth abundant semiconducting material, was conducted using an optimized Photo assisted Chemical Vapor Deposition process. X-Ray Diffraction, Ellipsometry, Transmission Electron Microscopy, and Profilometry revealed that the films composed of Cu2O of about 90 nm thickness and the grain size was as large as 600 nm. This result shows an improvement in material properties over previously grown thin films of Cu2O. Measurement of I-V characteristics of a diode structure composed of the Cu2O indicates an increase in On/Off ratio to 17,000 from the previous best value of 800. These results suggest that the electronic quality of the thin films deposited using our optimized process to be better than the results reported elsewhere. Using this optimized thin film forming technique, it is now possible to create a complete MJMT structure to improve the terrestrial commercial PV efficiency.

Recovering valuable metals from recycled photovoltaic modules.

PubMed

Yi, Youn Kyu; Kim, Hyun Soo; Tran, Tam; Hong, Sung Kil; Kim, Myong Jun

2014-07-01

Recovering valuable metals such as Si, Ag, Cu, and Al has become a pressing issue as end-of-life photovoltaic modules need to be recycled in the near future to meet legislative requirements in most countries. Of major interest is the recovery and recycling of high-purity silicon (> 99.9%) for the production of wafers and semiconductors. The value of Si in crystalline-type photovoltaic modules is estimated to be -$95/kW at the 2012 metal price. At the current installed capacity of 30 GW/yr, the metal value in the PV modules represents valuable resources that should be recovered in the future. The recycling of end-of-life photovoltaic modules would supply > 88,000 and 207,000 tpa Si by 2040 and 2050, respectively. This represents more than 50% of the required Si for module fabrication. Experimental testwork on crystalline Si modules could recover a > 99.98%-grade Si product by HNO3/NaOH leaching to remove Al, Ag, and Ti and other metal ions from the doped Si. A further pyrometallurgical smelting at 1520 degrees C using CaO-CaF2-SiO2 slag mixture to scavenge the residual metals after acid leaching could finally produce > 99.998%-grade Si. A process based on HNO3/NaOH leaching and subsequent smelting is proposed for recycling Si from rejected or recycled photovoltaic modules. Implications: The photovoltaic industry is considering options of recycling PV modules to recover metals such as Si, Ag, Cu, Al, and others used in the manufacturing of the PV cells. This is to retain its "green" image and to comply with current legislations in several countries. An evaluation of potential resources made available from PV wastes and the technologies used for processing these materials is therefore of significant importance to the industry. Of interest are the costs of processing and the potential revenues gained from recycling, which should determine the viability of economic recycling of PV modules in the future.

Evaluating the performance of a 50 kilowatt grid-connected photovoltaic system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chowdhury, B.H.; Muknahallipatn, S.; Cupal, J.J.

A 50-kilowatt solar photovoltaic (PV) system was built at the University of Wyoming (UW) in 1996. The system comprises of three sub-systems. The first sub-system, a 10 kW roof-integrated system is located on the roof of the Engineering Building. The second sub-system is a 5 kW rack-mounted, ballasted PV system located on another part of the roof. The third sub-system is a 35 kW shade structure and is located adjacent to the university's football stadium. The three sub-systems differ in their design strategy since each is being used for research and education at the university. Each sub-system, being located atmore » some distance away from one another, supplies a different part of the campus grid. Efforts are continuing for setting up a central monitoring system, which will receive data remotely from all locations. A part of this monitoring system is complete. The system as configured provides a great deal of flexibility, which is in turn demanded by the variety of signal types measured at each installation. Each installation requires measurement of multiple dc and ac voltages and currents and one slowly varying voltage (proportional to solar insolation). The simultaneous sampling, fast sample rate, and lowpass signal conditioning allow for accurate measurement of power factor and total harmonic distortion of the inverter outputs. Panel and inverter efficiencies can be determined via simultaneous DC and AC measurements. These performance monitors provide the essential data for characterization of the PV effect at the grid input, and enable the use of intelligent power factor correction and harmonic filtering. Monitoring of the system shows that the total harmonic distortion present in the ac power output is at or below the acceptable limit as recommended by IEEE 519-1992. The harmonic distortion worsens when the ac power reaches more than 3.8 kW. A number of reliability problems with PV modules and inverters have delayed full functionality of the system.« less

A fault diagnosis system for PV power station based on global partitioned gradually approximation method

NASA Astrophysics Data System (ADS)

Wang, S.; Zhang, X. N.; Gao, D. D.; Liu, H. X.; Ye, J.; Li, L. R.

2016-08-01

As the solar photovoltaic (PV) power is applied extensively, more attentions are paid to the maintenance and fault diagnosis of PV power plants. Based on analysis of the structure of PV power station, the global partitioned gradually approximation method is proposed as a fault diagnosis algorithm to determine and locate the fault of PV panels. The PV array is divided into 16x16 blocks and numbered. On the basis of modularly processing of the PV array, the current values of each block are analyzed. The mean current value of each block is used for calculating the fault weigh factor. The fault threshold is defined to determine the fault, and the shade is considered to reduce the probability of misjudgments. A fault diagnosis system is designed and implemented with LabVIEW. And it has some functions including the data realtime display, online check, statistics, real-time prediction and fault diagnosis. Through the data from PV plants, the algorithm is verified. The results show that the fault diagnosis results are accurate, and the system works well. The validity and the possibility of the system are verified by the results as well. The developed system will be benefit for the maintenance and management of large scale PV array.

Droop Control of Solar PV, Grid and Critical Load using Suppressing DC Current Injection Technique without Battery Storage

NASA Astrophysics Data System (ADS)

Dama Mr., Jayachandra; (Mrs. , Lini Mathew, Dr.; Srikanth Mr., G.

2017-08-01

This paper presents design of a sustainable solar Photo voltaic system for an Indian cities based residential/community house, integrated with grid, supporting it as supplementary sources, to meet energy demand of domestic loads. The role of renewable energy sources in Distributed Generation (DG) is increasingly being recognized as a supplement and an alternative to large conventional central power supply. Though centralized economic system that solely depends on cities is hampered due to energy deficiency, the use of solar energy in cities is never been tried widely due to technical inconvenience and high installation cost. To mitigate these problems, this paper proposes an optimized design of grid-tied PV system without storage which is suitable for Indian origin as it requires less installallation cost and supplies residential loads when the grid power is unavailable. The energy requirement is mainly fulfilled from PV energy module for critical load of a city located residential house and supplemented by grid/DG for base and peak load. The system has been developed for maximum daily household demand of 50kWp and can be scaled to any higher value as per requirement of individual/community building ranging from 50kWp to 60kWp as per the requirement. A simplified control system model has been developed to optimize and control flow of power from these sources. The simulation work, using MATLAB Simulink software for proposed energy management, has resulted in an optimal yield leading efficient power flow control of proposed system.

Lossless hybridization between photovoltaic and thermoelectric devices.

PubMed

Park, Kwang-Tae; Shin, Sun-Mi; Tazebay, Abdullah S; Um, Han-Don; Jung, Jin-Young; Jee, Sang-Won; Oh, Min-Wook; Park, Su-Dong; Yoo, Bongyoung; Yu, Choongho; Lee, Jung-Ho

2013-01-01

The optimal hybridization of photovoltaic (PV) and thermoelectric (TE) devices has long been considered ideal for the efficient harnessing solar energy. Our hybrid approach uses full spectrum solar energy via lossless coupling between PV and TE devices while collecting waste energy from thermalization and transmission losses from PV devices. Achieving lossless coupling makes the power output from the hybrid device equal to the sum of the maximum power outputs produced separately from individual PV and TE devices. TE devices need to have low internal resistances enough to convey photo-generated currents without sacrificing the PV fill factor. Concomitantly, a large number of p-n legs are preferred to drive a high Seebeck voltage in TE. Our simple method of attaching a TE device to a PV device has greatly improved the conversion efficiency and power output of the PV device (~30% at a 15°C temperature gradient across a TE device).

Lossless hybridization between photovoltaic and thermoelectric devices

PubMed Central

Park, Kwang-Tae; Shin, Sun-Mi; Tazebay, Abdullah S.; Um, Han-Don; Jung, Jin-Young; Jee, Sang-Won; Oh, Min-Wook; Park, Su-Dong; Yoo, Bongyoung; Yu, Choongho; Lee, Jung-Ho

2013-01-01

The optimal hybridization of photovoltaic (PV) and thermoelectric (TE) devices has long been considered ideal for the efficient harnessing solar energy. Our hybrid approach uses full spectrum solar energy via lossless coupling between PV and TE devices while collecting waste energy from thermalization and transmission losses from PV devices. Achieving lossless coupling makes the power output from the hybrid device equal to the sum of the maximum power outputs produced separately from individual PV and TE devices. TE devices need to have low internal resistances enough to convey photo-generated currents without sacrificing the PV fill factor. Concomitantly, a large number of p-n legs are preferred to drive a high Seebeck voltage in TE. Our simple method of attaching a TE device to a PV device has greatly improved the conversion efficiency and power output of the PV device (~30% at a 15°C temperature gradient across a TE device). PMID:23820973

77 FR 4368 - Advanced Energy Industries, Inc., Including On-Site Leased Workers From Mid Oregon Personnel...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-27

... Unemployment Insurance (UI) Wages Are Reported Through PV Powered, Currently Known as AE Solar Energy, Inc... Energy Industries purchased PV Powered, currently known as AE Solar Energy, Inc. in May 2010. Some... separate unemployment insurance (UI) tax account under the name PV Powered, currently known as AE Solar...

Climate, air quality and human health benefits of various solar photovoltaic deployment scenarios in China in 2030

NASA Astrophysics Data System (ADS)

Yang, Junnan; Li, Xiaoyuan; Peng, Wei; Wagner, Fabian; Mauzerall, Denise L.

2018-06-01

Solar photovoltaic (PV) electricity generation can greatly reduce both air pollutant and greenhouse gas emissions compared to fossil fuel electricity generation. The Chinese government plans to greatly scale up solar PV installation between now and 2030. However, different PV development pathways will influence the range of air quality and climate benefits. Benefits depend on how much electricity generated from PV is integrated into power grids and the type of power plant displaced. Using a coal-intensive power sector projection as the base case, we estimate the climate, air quality, and related human health benefits of various 2030 PV deployment scenarios. We use the 2030 government goal of 400 GW installed capacity but vary the location of PV installation and the extent of inter-provincial PV electricity transmission. We find that deploying distributed PV in the east with inter-provincial transmission maximizes potential CO2 reductions and air quality-related health benefits (4.2% and 1.2% decrease in national total CO2 emissions and air pollution-related premature deaths compared to the base case, respectively). Deployment in the east with inter-provincial transmission results in the largest benefits because it maximizes displacement of the dirtiest coal-fired power plants and minimizes PV curtailment, which is more likely to occur without inter-provincial transmission. We further find that the maximum co-benefits achieved with deploying PV in the east and enabling inter-provincial transmission are robust under various maximum PV penetration levels in both provincial and regional grids. We find large potential benefits of policies that encourage distributed PV deployment and facilitate inter-provincial PV electricity transmission in China.

Reliability and energy efficiency of zero energy homes (Conference Presentation)

NASA Astrophysics Data System (ADS)

Dhere, Neelkanth G.

2016-09-01

Photovoltaic (PV) modules and systems are being installed increasingly on residential homes to increase the proportion of renewable energy in the energy mix. The ultimate goal is to attain sustainability without subsidy. The prices of PV modules and systems have declined substantially during the recent years. They will be reduced further to reach grid parity. Additionally the total consumed energy must be reduced by making the homes more energy efficient. FSEC/UCF Researchers have carried out research on development of PV cells and systems and on reducing the energy consumption in homes and by small businesses. Additionally, they have provided guidance on PV module and system installation and to make the homes energy efficient. The produced energy is fed into the utility grid and the consumed energy is obtained from the utility grid, thus the grid is assisting in the storage. Currently the State of Florida permits net metering leading to equal charge for the produced and consumed electricity. This paper describes the installation of 5.29 KW crystalline silicon PV system on a south-facing tilt at approximately latitude tilt on a single-story, three-bedroom house. It also describes the computer program on Building Energy Efficiency and the processes that were employed for reducing the energy consumption of the house by improving the insulation, air circulation and windows, etc. Finally it describes actual consumption and production of electricity and the installation of additional crystalline silicon PV modules and balance of system to make it a zero energy home.

Wafer integrated micro-scale concentrating photovoltaics

NASA Astrophysics Data System (ADS)

Gu, Tian; Li, Duanhui; Li, Lan; Jared, Bradley; Keeler, Gordon; Miller, Bill; Sweatt, William; Paap, Scott; Saavedra, Michael; Das, Ujjwal; Hegedus, Steve; Tauke-Pedretti, Anna; Hu, Juejun

2017-09-01

Recent development of a novel micro-scale PV/CPV technology is presented. The Wafer Integrated Micro-scale PV approach (WPV) seamlessly integrates multijunction micro-cells with a multi-functional silicon platform that provides optical micro-concentration, hybrid photovoltaic, and mechanical micro-assembly. The wafer-embedded micro-concentrating elements is shown to considerably improve the concentration-acceptance-angle product, potentially leading to dramatically reduced module materials and fabrication costs, sufficient angular tolerance for low-cost trackers, and an ultra-compact optical architecture, which makes the WPV module compatible with commercial flat panel infrastructures. The PV/CPV hybrid architecture further allows the collection of both direct and diffuse sunlight, thus extending the geographic and market domains for cost-effective PV system deployment. The WPV approach can potentially benefits from both the high performance of multijunction cells and the low cost of flat plate Si PV systems.

Realworld maximum power point tracking simulation of PV system based on Fuzzy Logic control

NASA Astrophysics Data System (ADS)

Othman, Ahmed M.; El-arini, Mahdi M. M.; Ghitas, Ahmed; Fathy, Ahmed

2012-12-01

In the recent years, the solar energy becomes one of the most important alternative sources of electric energy, so it is important to improve the efficiency and reliability of the photovoltaic (PV) systems. Maximum power point tracking (MPPT) plays an important role in photovoltaic power systems because it maximize the power output from a PV system for a given set of conditions, and therefore maximize their array efficiency. This paper presents a maximum power point tracker (MPPT) using Fuzzy Logic theory for a PV system. The work is focused on the well known Perturb and Observe (P&O) algorithm and is compared to a designed fuzzy logic controller (FLC). The simulation work dealing with MPPT controller; a DC/DC Ćuk converter feeding a load is achieved. The results showed that the proposed Fuzzy Logic MPPT in the PV system is valid.

Results of the harmonics measurement program at the John F. Long photovoltaic house

NASA Astrophysics Data System (ADS)

Campen, G. L.

1982-03-01

Photovoltaic (PV) systems used in single-family dwellings require an inverter to act as an interface between the direct-current (dc) power output of the PV unit and the alternating-current (ac) power needed by house loads. A type of inverter known as line commutated injects harmonic currents on the ac side and requires large amounts of reactive power. Large numbers of such PV installations could lead to unacceptable levels of harmonic voltages on the utility system, and the need to increase the utility's deliver of reactive power could result in significant cost increases. The harmonics and power-factor effects are examined for a single PV installation using a line-commutated inverter. The magnitude and phase of various currents and voltages from the fundamental to the 13th harmonic were recorded both with and without the operation of the PV system.

Research on comprehensive decision-making of PV power station connecting system

NASA Astrophysics Data System (ADS)

Zhou, Erxiong; Xin, Chaoshan; Ma, Botao; Cheng, Kai

2018-04-01

In allusion to the incomplete indexes system and not making decision on the subjectivity and objectivity of PV power station connecting system, based on the combination of improved Analytic Hierarchy Process (AHP), Criteria Importance Through Intercriteria Correlation (CRITIC) as well as grey correlation degree analysis (GCDA) is comprehensively proposed to select the appropriate system connecting scheme of PV power station. Firstly, indexes of PV power station connecting system are divided the recursion order hierarchy and calculated subjective weight by the improved AHP. Then, CRITIC is adopted to determine the objective weight of each index through the comparison intensity and conflict between indexes. The last the improved GCDA is applied to screen the optimal scheme, so as to, from the subjective and objective angle, select the connecting system. Comprehensive decision of Xinjiang PV power station is conducted and reasonable analysis results are attained. The research results might provide scientific basis for investment decision.

Zinc Bromide Flow Battery Installation for Islanding and Backup Power

DTIC Science & Technology

2016-09-18

ability to control the generation has become more difficult with the increase of renewable energy systems such as solar photovoltaics ( PV ) and wind... PV and Inverter Room Building 6311 Rooftop Solar PV 30kW 232kW STC PV Array B5-PS2T33 Pad Switchboard ZnBr Energy Storage System (ESS) PowerBoxEnergy...Agreement • 1.5 MW of Photovoltaic • PV Parking lot lights • 24 Solar Thermal systems including the Combat Training Tank (Pool) Energy/Water Efficiency

Implications for current regulatory waste toxicity characterisation methods from analysing metal and metalloid leaching from photovoltaic modules

NASA Astrophysics Data System (ADS)

Collins, Mary Kayla; Anctil, Annick

2017-07-01

The appropriateness of regulatory methods to characterise the toxicity of photovoltaic (PV) modules was investigated to quantify potential environmental impacts for modules disposed of in landfills. Because solar energy is perceived as a green technology, it is important to ensure that end-of-life issues will not be detrimental to solar energy's success. United States Environmental Protection Agency Method 1311, California waste extraction test, and modified versions of both were performed on a multi-crystalline silicon module and cells and a copper indium gallium diselenide (CIGS) module. Variations in metal leachate concentrations were found with changes in testing parameters. Lead concentrations from the multi-crystalline module ranged from 16.2 to 50.2 mg/L. Cadmium concentrations from the CIGS module ranged from 0.1 to 3.52 mg/L. This raises doubt that regulatory methods can adequately characterise PV modules. The results are useful for developing end-of-life procedures, which is a positive step towards avoiding an e-waste problem and continuing trends of increasing installation and cost reduction in the PV market.

Design and Analysis of Photovoltaic (PV) Power Plant at Different Locations in Malaysia

NASA Astrophysics Data System (ADS)

Islam, M. A.; Hasanuzzaman, M.; Rahim, N. A.

2018-05-01

Power generation from sun oriented vitality through a photovoltaic (PV) system is ended up prevalent over the world due to clean innovation. Geographical location of Malaysia is very favorable for PV power generation system. The Malaysian government has also taken different steps to increase the use of solar energy especially by emphasizing on building integrated PV (BIPV) system. Comparative study on the feasibility of BIPV installation at the different location of Malaysia is rarely found. On the other hand, solar cell temperature has a negative impact on the electricity generation. So in this study cost effectiveness and initial investment cost of building integrated grid connected solar PV power plant in different regions of Malaysia have been carried. The effect of PV solar cell temperature on the payback period (PBP) is also investigated. Highest PBP is 12.38 years at Selangor and lowest PBP is 9.70 years at Sabah (Kota Kinabalu). Solar cell temperature significantly increases the PBP of PV plant and highest 14.64% and lowest 13.20% raise of PBP are encountered at Penang and Sarawak respectively.

Assessment of the biophysical impacts of utility-scale photovoltaics through observations and modelling

NASA Astrophysics Data System (ADS)

Broadbent, A. M.; Georgescu, M.; Krayenhoff, E. S.; Sailor, D.

2017-12-01

Utility-scale solar power plants are a rapidly growing component of the solar energy sector. Utility-scale photovoltaic (PV) solar power generation in the United States has increased by 867% since 2012 (EIA, 2016). This expansion is likely to continue as the cost PV technologies decrease. While most agree that solar power can decrease greenhouse gas emissions, the biophysical effects of PV systems on surface energy balance (SEB), and implications for surface climate, are not well understood. To our knowledge, there has never been a detailed observational study of SEB at a utility-scale solar array. This study presents data from an eddy covariance observational tower, temporarily placed above a utility-scale PV array in Southern Arizona. Comparison of PV SEB with a reference (unmodified) site, shows that solar panels can alter the SEB and near surface climate. SEB observations are used to develop and validate a new and more complete SEB PV model. In addition, the PV model is compared to simpler PV modelling methods. The simpler PV models produce differing results to our newly developed model and cannot capture the more complex processes that influence PV SEB. Finally, hypothetical scenarios of PV expansion across the continental United States (CONUS) were developed using various spatial mapping criteria. CONUS simulations of PV expansion reveal regional variability in biophysical effects of PV expansion. The study presents the first rigorous and validated simulations of the biophysical effects of utility-scale PV arrays.

Recycling WEEE: Polymer characterization and pyrolysis study for waste of crystalline silicon photovoltaic modules.

PubMed

Dias, Pablo; Javimczik, Selene; Benevit, Mariana; Veit, Hugo

2017-02-01

Photovoltaic (PV) modules contain both valuable and hazardous materials, which makes its recycling meaningful economically and environmentally. In general, the recycling of PV modules starts with the removal of the polymeric ethylene-vinyl acetate (EVA) resin using pyrolysis, which assists in the recovery of materials such as silicon, copper and silver. The pyrolysis implementation, however, needs improvement given its importance. In this study, the polymers in the PV modules were characterized by Fourier transform infrared spectroscopy (FTIR) and the removal of the EVA resin using pyrolysis has been studied and optimized. The results revealed that 30min pyrolysis at 500°C removes >99% of the polymers present in photovoltaic modules. Moreover, the behavior of different particle size milled modules during the pyrolysis process was evaluated. It is shown that polymeric materials tend to remain at a larger particle size and thus, this fraction has the greatest mass loss during pyrolysis. A thermo gravimetric analysis (TGA) performed in all polymeric matter revealed the optimum pyrolysis temperature is around 500°C. Temperatures above 500°C continue to degrade matter, but mass loss rate is 6.25 times smaller. This study demonstrates the use of pyrolysis can remove >99% of the polymeric matter from PV modules, which assists the recycling of this hazardous waste and avoids its disposal. Copyright © 2016 Elsevier Ltd. All rights reserved.

Modeling and Simulation of a DG-Integrated Intelligent Microgrid

DTIC Science & Technology

2010-02-01

17. The I-V curve from the manufacturer for BP-4175 175W PV module...........................32   Fig. 18. Wind turbine model...33   Fig. 19. Electrical outputs of wind turbine... PMSG : Permanent Magnet Synchronous Generator PLL : Phase Lock Loop PV : Photovoltaic PWM : Pulse Width Modulation TOU : Time of Use VTES

Spectral splitting for thermal management in photovoltaic cells

NASA Astrophysics Data System (ADS)

Apostoleris, Harry; Chiou, Yu-Cheng; Chiesa, Matteo; Almansouri, Ibraheem

2017-09-01

Spectral splitting is widely employed as a way to divide light between different solar cells or processes to optimize energy conversion. Well-understood but less explored is the use of spectrum splitting or filtering to combat solar cell heating. This has impacts both on cell performance and on the surrounding environment. In this manuscript we explore the design of spectral filtering systems that can improve the thermal and power-conversion performance of commercial PV modules.

Study on Battery Capacity for Grid-connection Power Planning with Forecasts in Clustered Photovoltaic Systems

NASA Astrophysics Data System (ADS)

Shimada, Takae; Kawasaki, Norihiro; Ueda, Yuzuru; Sugihara, Hiroyuki; Kurokawa, Kosuke

This paper aims to clarify the battery capacity required by a residential area with densely grid-connected photovoltaic (PV) systems. This paper proposes a planning method of tomorrow's grid-connection power from/to the external electric power system by using demand power forecasting and insolation forecasting for PV power predictions, and defines a operation method of the electricity storage device to control the grid-connection power as planned. A residential area consisting of 389 houses consuming 2390 MWh/year of electricity with 2390kW PV systems is simulated based on measured data and actual forecasts. The simulation results show that 8.3MWh of battery capacity is required in the conditions of half-hour planning and 1% or less of planning error ratio and PV output limiting loss ratio. The results also show that existing technologies of forecasting reduce required battery capacity to 49%, and increase the allowable installing PV amount to 210%.

To Own or Lease Solar: Understanding Commercial Retailers' Decisions to Use Alternative Financing Models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Feldman, David; Margolis, Robert

This report examines the tradeoffs among financing methods for businesses installing onsite photovoltaics (PV). We present case studies of PV financing strategies used by two large commercial retailers that have deployed substantial U.S. PV capacity: IKEA, which owns its PV, and Staples, which purchases power generated from onsite PV systems through power purchase agreements (PPAs). We also analyze the financial considerations that influence any company's choice of PV financing strategy. Our goal in this report is to clarify the financial and institutional costs and benefits of financing strategies and to inform other companies that are considering launching or expanding similarmore » PV programs.« less

Advanced Grid-Friendly Controls Demonstration Project for Utility-Scale PV Power Plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gevorgian, Vahan; O'Neill, Barbara

A typical photovoltaic (PV) power plant consists of multiple power electronic inverters and can contribute to grid stability and reliability through sophisticated 'grid-friendly' controls. The availability and dissemination of actual test data showing the viability of advanced utility-scale PV controls among all industry stakeholders can leverage PV's value from being simply an energy resource to providing additional ancillary services that range from variability smoothing and frequency regulation to power quality. Strategically partnering with a selected utility and/or PV power plant operator is a key condition for a successful demonstration project. The U.S. Department of Energy's (DOE's) Solar Energy Technologies Officemore » selected the National Renewable Energy Laboratory (NREL) to be a principal investigator in a two-year project with goals to (1) identify a potential partner(s), (2) develop a detailed scope of work and test plan for a field project to demonstrate the gird-friendly capabilities of utility-scale PV power plants, (3) facilitate conducting actual demonstration tests, and (4) disseminate test results among industry stakeholders via a joint NREL/DOE publication and participation in relevant technical conferences. The project implementation took place in FY 2014 and FY 2015. In FY14, NREL established collaborations with AES and First Solar Electric, LLC, to conduct demonstration testing on their utility-scale PV power plants in Puerto Rico and Texas, respectively, and developed test plans for each partner. Both Puerto Rico Electric Power Authority and the Electric Reliability Council of Texas expressed interest in this project because of the importance of such advanced controls for the reliable operation of their power systems under high penetration levels of variable renewable generation. During FY15, testing was completed on both plants, and a large amount of test data was produced and analyzed that demonstrates the ability of PV power plants to provide various types of new grid-friendly controls.« less

Impact of Balance Of System (BOS) costs on photovoltaic power systems

NASA Technical Reports Server (NTRS)

Hein, G. F.; Cusick, J. P.; Poley, W. A.

1978-01-01

The Department of Energy has developed a program to effect a large reduction in the price of photovoltaic modules, with significant progress already achieved toward the 1986 goal of 50 cents/watt (1975 dollars). Remaining elements of a P/V power system (structure, battery storage, regulation, control, and wiring) are also significant cost items. The costs of these remaining elements are commonly referred to as Balance-of-System (BOS) costs. The BOS costs are less well defined and documented than module costs. The Lewis Research Center (LeRC) in 1976/77 and with two village power experiments that will be installed in 1978. The costs were divided into five categories and analyzed. A regression analysis was performed to determine correlations of BOS Costs per peak watt, with power size for these photovoltaic systems. The statistical relationship may be used for flat-plate, DC systems ranging from 100 to 4,000 peak watts. A survey of suppliers was conducted for comparison with the predicted BOS cost relationship.

New prospects for PV powered water desalination plants: case studies in Saudi Arabia: New prospects for PV powered water desalination plants

DOE PAGES

Fthenakis, Vasilis; Atia, Adam A.; Morin, Olivier; ...

2015-01-28

Increased water demand and increased drought episodes in the Middle East and other regions necessitate an expansion in desalination projects and create a great market opportunity for photovoltaics (PV). PV-powered desalination has previously been regarded as not being a cost-competitive solution when compared with conventionally powered desalination; however, the decline in PV costs over the last few years has changed this outlook. Here, this article presents up-to-date performance and cost analysis of reverse osmosis (RO) desalination powered with PV connected to the Saudi Arabian grid. Reference cases include relatively small (i.e., producing 6550 m 3 water per day) and largemore » (i.e., 190 000 m 3/day) desalination plants using seawater at a salinity of 40 000 ppm. We used data from a King Abdullah University for Science and Technology presentation and Hybrid Optimization Model for Electric Renewables 2.81 Energy Modeling Software (HOMER Energy LLC) in tandem with Desalination Economic Evaluation Program 4.0 (International Atomic Energy Agency) desalination software to analyze the techno-economic feasibility of these plants. The first phase of our work entailed a comparison between dual-axis high concentration PV (CPV) equipped with triple junction III/V solar cells and CdTe PV-powered RO systems. The estimated levelized cost of electricity from CPV is 0.16/kWh dollars, whereas that from CdTe PV is $0.10/kWh dollars and 0.09/kWh dollars for fixed-tilt and one-axis tracking systems, respectively. These costs are higher than the price of diesel-based grid electricity in the region because diesel fuel is heavily subsidized in Saudi Arabia.« less

Environmental aging in polycrystalline-Si photovoltaic modules: comparison of chamber-based accelerated degradation studies with field-test data

NASA Astrophysics Data System (ADS)

Lai, T.; Biggie, R.; Brooks, A.; Potter, B. G.; Simmons-Potter, K.

2015-09-01

Lifecycle degradation testing of photovoltaic (PV) modules in accelerated-degradation chambers can enable the prediction both of PV performance lifetimes and of return-on-investment for installations of PV systems. With degradation results strongly dependent on chamber test parameters, the validity of such studies relative to fielded, installed PV systems must be determined. In the present work, accelerated aging of a 250 W polycrystalline silicon module is compared to real-time performance degradation in a similar polycrystalline-silicon, fielded, PV technology that has been operating since October 2013. Investigation of environmental aging effects are performed in a full-scale, industrial-standard environmental chamber equipped with single-sun irradiance capability providing illumination uniformity of 98% over a 2 x 1.6 m area. Time-dependent, photovoltaic performance (J-V) is evaluated over a recurring, compressed night-day cycle providing representative local daily solar insolation for the southwestern United States, followed by dark (night) cycling. This cycle is synchronized with thermal and humidity environmental variations that are designed to mimic, as closely as possible, test-yard conditions specific to a 12 month weather profile for a fielded system in Tucson, AZ. Results confirm the impact of environmental conditions on the module long-term performance. While the effects of temperature de-rating can be clearly seen in the data, removal of these effects enables the clear interpretation of module efficiency degradation with time and environmental exposure. With the temperature-dependent effect removed, the normalized efficiency is computed and compared to performance results from another panel of similar technology that has previously experienced identical climate changes in the test yard. Analysis of relative PV module efficiency degradation for the chamber-tested system shows good comparison to the field-tested system with ~2.5% degradation following an equivalent year of testing.

Output Control Technologies for a Large-scale PV System Considering Impacts on a Power Grid

NASA Astrophysics Data System (ADS)

Kuwayama, Akira

The mega-solar demonstration project named “Verification of Grid Stabilization with Large-scale PV Power Generation systems” had been completed in March 2011 at Wakkanai, the northernmost city of Japan. The major objectives of this project were to evaluate adverse impacts of large-scale PV power generation systems connected to the power grid and develop output control technologies with integrated battery storage system. This paper describes the outline and results of this project. These results show the effectiveness of battery storage system and also proposed output control methods for a large-scale PV system to ensure stable operation of power grids. NEDO, New Energy and Industrial Technology Development Organization of Japan conducted this project and HEPCO, Hokkaido Electric Power Co., Inc managed the overall project.

A Novel Technique for Maximum Power Point Tracking of a Photovoltaic Based on Sensing of Array Current Using Adaptive Neuro-Fuzzy Inference System (ANFIS)

NASA Astrophysics Data System (ADS)

El-Zoghby, Helmy M.; Bendary, Ahmed F.

2016-10-01

Maximum Power Point Tracking (MPPT) is now widely used method in increasing the photovoltaic (PV) efficiency. The conventional MPPT methods have many problems concerning the accuracy, flexibility and efficiency. The MPP depends on the PV temperature and solar irradiation that randomly varied. In this paper an artificial intelligence based controller is presented through implementing of an Adaptive Neuro-Fuzzy Inference System (ANFIS) to obtain maximum power from PV. The ANFIS inputs are the temperature and cell current, and the output is optimal voltage at maximum power. During operation the trained ANFIS senses the PV current using suitable sensor and also senses the temperature to determine the optimal operating voltage that corresponds to the current at MPP. This voltage is used to control the boost converter duty cycle. The MATLAB simulation results shows the effectiveness of the ANFIS with sensing the PV current in obtaining the MPPT from the PV.

Developing High PV Penetration Cases for Frequency Response Study of U.S. Western Interconnection: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tan, Jin; Zhang, Yingchen; Veda, Santosh

Recent large penetrations of solar photovoltaic (PV) generation and the inertial characteristics of inverter-based generation technologies have caught the attention of those in the electric power industry in the United States. This paper presents a systematic approach to developing test cases of high penetrations of PV for the Western Interconnection. First, to examine the accuracy of the base case model, the Western Electricity Coordinating Council (WECC) model is validated by using measurement data from synchronized phasor measurement units. Based on the 2022 Light Spring case, we developed four high PV penetration cases for the WECC system that are of interestmore » to the industry: 5% PV+15 % wind, 25% PV+15% wind, 45% PV+15% wind, 65% PV+15% wind). Additionally, a method to project PV is proposed that is based on collected, realistic PV distribution information, including the current and future PV power plant locations and penetrations in the WECC system. Both the utility-scale PV plant and residential rooftop PV are included in this study.« less

Developing High PV Penetration Cases for Frequency Response Study of U.S. Western Interconnection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tan, Jin; Zhang, Yingchen; Veda, Santosh

Recent large penetrations of solar photovoltaic (PV) generation and the inertial characteristics of inverter-based generation technologies have caught the attention of those in the electric power industry in the United States. This paper presents a systematic approach to developing test cases of high penetrations of PV for the Western Interconnection. First, to examine the accuracy of the base case model, the Western Electricity Coordinating Council (WECC) model is validated by using measurement data from synchronized phasor measurement units. Based on the 2022 Light Spring case, we developed four high PV penetration cases for the WECC system that are of interestmore » to the industry: 5% PV+15 % wind, 25% PV+15% wind, 45% PV+15% wind, 65% PV+15% wind). Additionally, a method to project PV is proposed that is based on collected, realistic PV distribution information, including the current and future PV power plant locations and penetrations in the WECC system. Both the utility-scale PV plant and residential rooftop PV are included in this study.« less

Developing High PV Penetration Cases for Frequency Response Study of U.S. Western Interconnection: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tan, Jin; Zhang, Yingchen; Veda, Santosh

2017-04-11

Recent large penetrations of solar photovoltaic (PV) generation and the inertial characteristics of inverter-based generation technologies have caught the attention of those in the electric power industry in the United States. This paper presents a systematic approach to developing test cases of high penetrations of PV for the Western Interconnection. First, to examine the accuracy of the base case model, the Western Electricity Coordinating Council (WECC) model is validated by using measurement data from synchronized phasor measurement units. Based on the 2022 Light Spring case, we developed four high PV penetration cases for the WECC system that are of interestmore » to the industry: 5% PV+15 % wind, 25% PV+15% wind, 45% PV+15% wind, 65% PV+15% wind). Additionally, a method to project PV is proposed that is based on collected, realistic PV distribution information, including the current and future PV power plant locations and penetrations in the WECC system. Both the utility-scale PV plant and residential rooftop PV are included in this study.« less

A Two-Stage Stochastic Mixed-Integer Programming Approach to the Smart House Scheduling Problem

NASA Astrophysics Data System (ADS)

Ozoe, Shunsuke; Tanaka, Yoichi; Fukushima, Masao

A “Smart House” is a highly energy-optimized house equipped with photovoltaic systems (PV systems), electric battery systems, fuel cell cogeneration systems (FC systems), electric vehicles (EVs) and so on. Smart houses are attracting much attention recently thanks to their enhanced ability to save energy by making full use of renewable energy and by achieving power grid stability despite an increased power draw for installed PV systems. Yet running a smart house's power system, with its multiple power sources and power storages, is no simple task. In this paper, we consider the problem of power scheduling for a smart house with a PV system, an FC system and an EV. We formulate the problem as a mixed integer programming problem, and then extend it to a stochastic programming problem involving recourse costs to cope with uncertain electricity demand, heat demand and PV power generation. Using our method, we seek to achieve the optimal power schedule running at the minimum expected operation cost. We present some results of numerical experiments with data on real-life demands and PV power generation to show the effectiveness of our method.

Learning curve approach to projecting cost and performance for photovoltaic technologies

NASA Astrophysics Data System (ADS)

Cody, George D.; Tiedje, Thomas

1997-10-01

The current cost of electricity generated by PV power is still extremely high with respect to power supplied by the utility grid, and there remain questions as to whether PV power can ever be competitive with electricity generated by fossil fuels. An objective approach to this important question was given in a previous paper by the authors which introduced analytical tools to define and project the technical/economic status of PV power from 1988 through the year 2010. In this paper, we apply these same tools to update the conclusions of our earlier study in the context of recent announcements by Amoco/Enron-Solar of projected sales of PV power at rates significantly less than the U.S. utility average.

A learning curve approach to projecting cost and performance for photovoltaic technologies

NASA Astrophysics Data System (ADS)

Cody, George D.; Tiedje, Thomas

1997-04-01

The current cost of electricity generated by PV power is still extremely high with respect to power supplied by the utility grid, and there remain questions as to whether PV power can ever be competitive with electricity generated by fossil fuels. An objective approach to this important question was given in a previous paper by the authors which introduced analytical tools to define and project the technical/economic status of PV power from 1988 through the year 2010. In this paper, we apply these same tools to update the conclusions of our earlier study in the context of recent announcements by Amoco/Enron-Solarex of projected sales of PV power at rates significantly less than the US utility average.

2014 NREL Photovoltaic Reliability Workshops | Photovoltaic Research | NREL

Science.gov Websites

Curves and Visual Inspection of PV Modules Deployed at TEP Solar Test Yard-Peter McNutt, NREL Data Determining PV System's Degradation Rate and the Impact of Data Filters-Wilson Zexu Zhang, REC Solar Pte. Ltd " Test in Qualifying Solar PV Inverters-Dutch Uselton, Lennox IND System Reliability for Utility PV

Chapter 10.2: Encapsulant Materials for PV Modules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kempe, Michael D

2017-01-07

Encapsulant materials used in photovoltaic (PV) modules serve multiple purposes; it provides optical coupling of PV cells and protection against environmental stress. Polymers must perform these functions under prolonged periods of high temperature, humidity, and UV radiation. When PV panels were first developed in the 1960s and the 1970s, the dominant encapsulants were based on polydimethyl siloxane (PDMS). Ethylene-co-vinyl acetate (EVA) is currently the dominant encapsulant chosen for PV applications, not because it has the best combination of properties, but because it is an economical option with an established history of acceptable durability. Getting new products onto the market ismore » challenging because there is no room for dramatic improvements, and one must balance the initial cost and performance with the unknowns of long-term service life. Recently, there has been renewed interest in using alternative encapsulant materials with some significant manufacturers switching from EVA to polyolefin elastomer-based (POE) alternatives.« less

Market assessment of photovoltaic power systems for agricultural applications in Morocco

NASA Technical Reports Server (NTRS)

Steingass, H.; Asmon, I.

1981-01-01

Results of a month-long study in Morocco aimed at assessing the market potential for stand-alone photovoltaic systems in agriculture and rural service applications are presented. The following applications, requiring less than 15 kW of power, are described: irrigation, cattle watering, refrigeration, crop processing, potable water and educational TV. Telecommunications and transportation signalling applications, descriptions of power and energy use profiles, assessments of business environment, government and private sector attitudes towards photovoltaics, and financing were also considered. The Moroccan market presents both advantages and disadvantages for American PV manufacturers. The principle advantages of the Moroccan market are: a limited grid, interest in and present use of PV in communications applications, attractive investment incentives, and a stated policy favoring American investment. Disadvantages include: lack of government incentives for PV use, general unfamiliarity with PV technology, high first cost of PV, a well-established market network for diesel generators, and difficulty with financing. The market for PV in Morocco (1981-1986), will be relatively small, about 340 kwp. The market for PV is likely to be more favorable in telecommunications, transport signalling and some rural services. The primary market appears to be in the public (i.e., government) rather than private sector, due to financial constraints and the high price of PV relative to conventional power sector.

Market assessment of photovoltaic power systems for agricultural applications in Morocco

NASA Astrophysics Data System (ADS)

Steingass, H.; Asmon, I.

1981-09-01

Results of a month-long study in Morocco aimed at assessing the market potential for stand-alone photovoltaic systems in agriculture and rural service applications are presented. The following applications, requiring less than 15 kW of power, are described: irrigation, cattle watering, refrigeration, crop processing, potable water and educational TV. Telecommunications and transportation signalling applications, descriptions of power and energy use profiles, assessments of business environment, government and private sector attitudes towards photovoltaics, and financing were also considered. The Moroccan market presents both advantages and disadvantages for American PV manufacturers. The principle advantages of the Moroccan market are: a limited grid, interest in and present use of PV in communications applications, attractive investment incentives, and a stated policy favoring American investment. Disadvantages include: lack of government incentives for PV use, general unfamiliarity with PV technology, high first cost of PV, a well-established market network for diesel generators, and difficulty with financing. The market for PV in Morocco (1981-1986), will be relatively small, about 340 kwp. The market for PV is likely to be more favorable in telecommunications, transport signalling and some rural services. The primary market appears to be in the public (i.e., government) rather than private sector, due to financial constraints and the high price of PV relative to conventional power sector.

Is $50/MWh solar for real? Falling project prices and rising capacity factors drive utility-scale PV toward economic competitiveness

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bolinger, Mark; Weaver, Samantha; Zuboy, Jarett

Recently announced low-priced power purchase agreements (PPAs) for US utility-scale photovoltaic (PV) projects suggest $50/MWh solar might be viable under certain conditions. To explore this possibility, this paper draws on an increasing wealth of empirical data to analyze trends in three of the most important PPA price drivers: upfront installed project prices, operations, and maintenance (O&M) costs, and capacity factors. Average installed prices among a sample of utility-scale PV projects declined by more than one third (from 5.8/W AC to 3.7/WAC) from the 2007–2009 period through 2013, even as costlier systems with crystalline-silicon modules, sun tracking, and higher inverter loadingmore » ratios (ILRs) have constituted an increasing proportion of total utility-scale PV capacity (all values shown here are in 2013 dollars). Actual and projected O&M costs from a very small sample of projects appear to range from $20–$40/kW AC-year. Furthermore, the average net capacity factor is 30% for projects installed in 2012, up from 24% for projects installed in 2010, owing to better solar resources, higher ILRs, and greater use of tracking among the more recent projects. Based on these trends, a pro-forma financial model suggests that $50/MWh utility-scale PV is achievable using a combination of aggressive-but-achievable technical and financial input parameters (including receipt of the 30% federal investment tax credit). Although the US utility-scale PV market is still young, the rapid progress in the key metrics documented in this paper has made PV a viable competitor against other utility-scale renewable generators, and even conventional peaking generators, in certain regions of the country.« less

Is $50/MWh solar for real? Falling project prices and rising capacity factors drive utility-scale PV toward economic competitiveness

DOE PAGES

Bolinger, Mark; Weaver, Samantha; Zuboy, Jarett

2015-05-22

Recently announced low-priced power purchase agreements (PPAs) for US utility-scale photovoltaic (PV) projects suggest $50/MWh solar might be viable under certain conditions. To explore this possibility, this paper draws on an increasing wealth of empirical data to analyze trends in three of the most important PPA price drivers: upfront installed project prices, operations, and maintenance (O&M) costs, and capacity factors. Average installed prices among a sample of utility-scale PV projects declined by more than one third (from 5.8/W AC to 3.7/WAC) from the 2007–2009 period through 2013, even as costlier systems with crystalline-silicon modules, sun tracking, and higher inverter loadingmore » ratios (ILRs) have constituted an increasing proportion of total utility-scale PV capacity (all values shown here are in 2013 dollars). Actual and projected O&M costs from a very small sample of projects appear to range from $20–$40/kW AC-year. Furthermore, the average net capacity factor is 30% for projects installed in 2012, up from 24% for projects installed in 2010, owing to better solar resources, higher ILRs, and greater use of tracking among the more recent projects. Based on these trends, a pro-forma financial model suggests that $50/MWh utility-scale PV is achievable using a combination of aggressive-but-achievable technical and financial input parameters (including receipt of the 30% federal investment tax credit). Although the US utility-scale PV market is still young, the rapid progress in the key metrics documented in this paper has made PV a viable competitor against other utility-scale renewable generators, and even conventional peaking generators, in certain regions of the country.« less

Performance test of a grid-tied PV system to power a split air conditioner system in Surabaya

NASA Astrophysics Data System (ADS)

Tarigan, E.

2017-11-01

Air conditioner for cooling air is one of the major needs for those who live in hot climate area such as Indonesia. This work presents the performance test of a grid-tied PV system to power air conditioner under a hot tropical climate in Surabaya, Indonesia. A 800 WP grid-tied photovoltaic (PV) system was used, and its performance was tested to power a 0.5 pk of split air conditioner system. It was found that about 3.5 kWh daily energy was consumed by the tested air conditioner system, and about 80% it could be supplied from the PV system. While the other 20% was supplied by the grid during periods of low solar irradiation, 440 Wh of energy was fed into the grid during operation out of office hours. By using the grid-tied PV system, the energy production by PV system did not need to match the consumption of the air conditioner. However, a larger capacity of PV system would mean that a higher percentage of the load would be covered by PV system.

A Smart Power Electronic Multiconverter for the Residential Sector.

PubMed

Guerrero-Martinez, Miguel Angel; Milanes-Montero, Maria Isabel; Barrero-Gonzalez, Fermin; Miñambres-Marcos, Victor Manuel; Romero-Cadaval, Enrique; Gonzalez-Romera, Eva

2017-05-26

The future of the grid includes distributed generation and smart grid technologies. Demand Side Management (DSM) systems will also be essential to achieve a high level of reliability and robustness in power systems. To do that, expanding the Advanced Metering Infrastructure (AMI) and Energy Management Systems (EMS) are necessary. The trend direction is towards the creation of energy resource hubs, such as the smart community concept. This paper presents a smart multiconverter system for residential/housing sector with a Hybrid Energy Storage System (HESS) consisting of supercapacitor and battery, and with local photovoltaic (PV) energy source integration. The device works as a distributed energy unit located in each house of the community, receiving active power set-points provided by a smart community EMS. This central EMS is responsible for managing the active energy flows between the electricity grid, renewable energy sources, storage equipment and loads existing in the community. The proposed multiconverter is responsible for complying with the reference active power set-points with proper power quality; guaranteeing that the local PV modules operate with a Maximum Power Point Tracking (MPPT) algorithm; and extending the lifetime of the battery thanks to a cooperative operation of the HESS. A simulation model has been developed in order to show the detailed operation of the system. Finally, a prototype of the multiconverter platform has been implemented and some experimental tests have been carried out to validate it.

A Smart Power Electronic Multiconverter for the Residential Sector

PubMed Central

Guerrero-Martinez, Miguel Angel; Milanes-Montero, Maria Isabel; Barrero-Gonzalez, Fermin; Miñambres-Marcos, Victor Manuel; Romero-Cadaval, Enrique; Gonzalez-Romera, Eva

2017-01-01

The future of the grid includes distributed generation and smart grid technologies. Demand Side Management (DSM) systems will also be essential to achieve a high level of reliability and robustness in power systems. To do that, expanding the Advanced Metering Infrastructure (AMI) and Energy Management Systems (EMS) are necessary. The trend direction is towards the creation of energy resource hubs, such as the smart community concept. This paper presents a smart multiconverter system for residential/housing sector with a Hybrid Energy Storage System (HESS) consisting of supercapacitor and battery, and with local photovoltaic (PV) energy source integration. The device works as a distributed energy unit located in each house of the community, receiving active power set-points provided by a smart community EMS. This central EMS is responsible for managing the active energy flows between the electricity grid, renewable energy sources, storage equipment and loads existing in the community. The proposed multiconverter is responsible for complying with the reference active power set-points with proper power quality; guaranteeing that the local PV modules operate with a Maximum Power Point Tracking (MPPT) algorithm; and extending the lifetime of the battery thanks to a cooperative operation of the HESS. A simulation model has been developed in order to show the detailed operation of the system. Finally, a prototype of the multiconverter platform has been implemented and some experimental tests have been carried out to validate it. PMID:28587131

75 FR 65306 - Notice of Intent To Prepare an Environmental Impact Statement for a Proposed Federal Loan...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-22

... installation of about nine million photovoltaic (PV) solar modules within approximately 437 arrays and... final project design. The proposed Project would consist of: A solar field of ground-mounted PV modules... Federal Loan Guarantee To Support Construction of the Topaz Solar Farm, San Luis Obispo County, CA AGENCY...

Assessing the Causes of Encapsulant Delamination in PV Modules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wohlgemuth, John H.; Hacke, Peter; Bosco, Nick

Delamination of the encapsulant is one of the most prevalent PV module field failures. This paper will present examples of various types of delaminations that have been observed in the field. It will then discuss the development of accelerated stress tests designed to duplicate those field failures and thus provide tools for avoiding them in the future.

Module Degradation Mechanisms Studied by a Multi-Scale Approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnston, Steve; Al-Jassim, Mowafak; Hacke, Peter

2016-11-21

A key pathway to meeting the Department of Energy SunShot 2020 goals is to reduce financing costs by improving investor confidence through improved photovoltaic (PV) module reliability. A comprehensive approach to further understand and improve PV reliability includes characterization techniques and modeling from module to atomic scale. Imaging techniques, which include photoluminescence, electroluminescence, and lock-in thermography, are used to locate localized defects responsible for module degradation. Small area samples containing such defects are prepared using coring techniques and are then suitable and available for microscopic study and specific defect modeling and analysis.

75 FR 52322 - Nationwide Limited Public Interest Waiver Under Section 1605 (Buy American) of the American...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-25

... ancillary solar Photovoltaic (PV) equipment, when this equipment is utilized in solar installations... following solar PV equipment: (1) Domestically- manufactured modules containing foreign-manufactured cells... effect. Solar cells are the basic building block of PV technologies. The cells are functional...

76 FR 55892 - Nationwide Limited Public Interest Waiver Under Section 1605 (Buy American) of the American...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-09

... following solar photo-voltaic (PV) equipment: (1) Domestically-manufactured modules containing foreign... inconsistent with the public interest for incidental and/or ancillary solar Photovoltaic (PV) equipment, when this equipment is utilized in solar installations containing domestically manufactured PV cells or...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pern, F.J.; Czanderna, A.W.

Yellow-browning of the ethylene-vinyl acetate (EVA) copolymer encapsulant used in PV modules has resulted in significant power losses of over 50% of the initial power output. The weathering-degraded yellow-brown EVA films have lost the ultraviolet (UV) absorber, Cyasorb UV 531[sup (R)], and the degree of cross-linking (gel content) has increased. EVA degradation mechanisms identified thus far are discussed in this work. Upon exposure to UV light at 45[degree]--85 [degree]C, virgin EVA films that are stabilized with Cyasorb UV 531[sup (R)] and two antioxidants show an increase in the gel content, a gradual loss of Cyasorb by photooxidation, and the generationmore » of acetic acid. The deacetylation reaction, which leads to the formation of polyenes, also occurs significantly in the films heated in the dark at 130 [degree]C for five days. Acetic acid thermally catalyzes the EVA film discoloration at 85[degree]--130 [degree]C, which increases from a light yellow to a yellow-brown color as the heating temperature increases. The factors can account for the yellow-browning of the EVA in the accelerated testing of mini-modules, and the discoloration is more profound when exposed to UV light at 85 [degree]C than when heated in the dark at the same temperature. In the presence of the EVA-produced acetic acid, oxygen, and sunlight exposure, the Cu buslines that were coated with a thin layer of Pb-Sn alloy showed significant oxidation and metal interdiffusion, which in turn may contribute to the resistance increase and hence the current loss reported for weathered PV modules.« less

Activities of the task group 8 on thin film PV module reliability (Conference Presentation)

NASA Astrophysics Data System (ADS)

Dhere, Neelkanth G.

2016-09-01

Photovoltaic (PV) modules and systems are being used increasingly to provide renewable energy to schools, residences, small businesses and utilities. At this time, the home owners and small businesses have considerable difficulty in detecting module and/or system degradation and especially enforcing warranty. It needs to be noted that IEC 61215-1 (test req.), -2 (test proc.) and -1-1 (c-Si) are forecasted to be circulated end of Feb 2016 and only editorial changes would be possible. 61215 series does include thin film technologies and would be replacing 61646. Moreover, IEC 61215-1, section 7.2 power output and electric circuitry does contain significant changes to acceptance criteria regarding rated label values, particularly rated power. Even though it is believed that consensus could be achieved within IEC TC82 WG2, some of the smaller players that do not participate actively in IEC TC82 - may not be surprised and must be informed. The other tech specific parts 61215-1-2 (CdTe), -1-3 (a-Si, µc-Si) and -1-4 (CIS, CIGS) are out for comments. The IEC closing date was January 29, 2016. The additions alternative damp heat (DH) test proposed Solar Frontier is being reviewed. In the past, only 600 V systems were permitted in the grid-connected residential and commercial systems in the US. The US commercial systems can now use higher voltage (1,000-1500V) in order to reduce BOS component costs. It is believed that there would not be any problems. The Task Group 8 is collecting data on higher voltage systems.

DISTRIBUTED GRID-CONNECTED PHOTOVOLTAIC POWER SYSTEM EMISSION OFFSET ASSESSMENT: STATISTICAL TEST OF SIMULATED- AND MEASURED-BASED DATA

EPA Science Inventory

This study assessed the pollutant emission offset potential of distributed grid-connected photovoltaic (PV) power systems. Computer-simulated performance results were utilized for 211 PV systems located across the U.S. The PV systems' monthly electrical energy outputs were based ...

Resource recovery from urban stock, the example of cadmium and tellurium from thin film module recycling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Simon, F.-G., E-mail: franz-georg.simon@bam.de; Holm, O.; Berger, W.

2013-04-15

Highlights: ► The semiconductor layer on thin-film photovoltaic modules can be removed from the glass-plate by vacuum blast cleaning. ► The separation of blasting agent and semiconductor can be performed using flotation with a valuable yield of 55%. ► PV modules are a promising source for the recovery of tellurium in the future. - Abstract: Raw material supply is essential for all industrial activities. The use of secondary raw material gains more importance since ore grade in primary production is decreasing. Meanwhile urban stock contains considerable amounts of various elements. Photovoltaic (PV) generating systems are part of the urban stockmore » and recycling technologies for PV thin film modules with CdTe as semiconductor are needed because cadmium could cause hazardous environmental impact and tellurium is a scarce element where future supply might be constrained. The paper describes a sequence of mechanical processing techniques for end-of-life PV thin film modules consisting of sandblasting and flotation. Separation of the semiconductor material from the glass surface was possible, however, enrichment and yield of valuables in the flotation step were non-satisfying. Nevertheless, recovery of valuable metals from urban stock is a viable method for the extension of the availability of limited natural resources.« less

The impact of climate change on photovoltaic power generation in Europe

PubMed Central

Jerez, Sonia; Tobin, Isabelle; Vautard, Robert; Montávez, Juan Pedro; López-Romero, Jose María; Thais, Françoise; Bartok, Blanka; Christensen, Ole Bøssing; Colette, Augustin; Déqué, Michel; Nikulin, Grigory; Kotlarski, Sven; van Meijgaard, Erik; Teichmann, Claas; Wild, Martin

2015-01-01

Ambitious climate change mitigation plans call for a significant increase in the use of renewables, which could, however, make the supply system more vulnerable to climate variability and changes. Here we evaluate climate change impacts on solar photovoltaic (PV) power in Europe using the recent EURO-CORDEX ensemble of high-resolution climate projections together with a PV power production model and assuming a well-developed European PV power fleet. Results indicate that the alteration of solar PV supply by the end of this century compared with the estimations made under current climate conditions should be in the range (−14%;+2%), with the largest decreases in Northern countries. Temporal stability of power generation does not appear as strongly affected in future climate scenarios either, even showing a slight positive trend in Southern countries. Therefore, despite small decreases in production expected in some parts of Europe, climate change is unlikely to threaten the European PV sector. PMID:26658608

Impact of PID on industrial rooftop PV-installations

NASA Astrophysics Data System (ADS)

Buerhop, Claudia; Fecher, Frank W.; Pickel, Tobias; Patel, Tirth; Zetzmann, Cornelia; Camus, Christian; Hauch, Jens; Brabec, Christoph J.

2017-08-01

Potential induced degradation (PID) causes severe damage and financial losses even in modern PV-installations. In Germany, approximately 19% of PV-installations suffer from PID and resulting power loss. This paper focuses on the impact of PID in real installations and how different evaluated time intervals influence the performance ratio (PR) and the determined degradation rate. The analysis focuses exemplarily on a 314 kWp PV-system in the Atlantic coastal climate. IR-imaging is used for identifying PID without operation interruption. Historic electric performance data are available from a monitoring system for several years on system level, string level as well as punctually measured module string IV- curves. The data sets are combined for understanding the PID behavior of this PV plant. The number of PID affected cells within a string varies strongly between 1 to 22% with the string position on the building complex. With increasing number of PID-affected cells the performance ratio decreases down to 60% for daily and monthly periods. Local differences in PID evolution rates are identified. An average PR-reduction of -3.65% per year is found for the PV-plant. On the string level the degradation rate varied up to 8.8% per year depending on the string position and the time period. The analysis reveals that PID generation and evolution in roof-top installations on industrial buildings with locally varying operation conditions can be fairly complex. The results yield that local operating conditions, e.g. ambient weather conditions as well as surrounding conditions on an industrial building, seem to have a dominating impact on the PID evolution rate.

A New MPPT Control for Photovoltaic Panels by Instantaneous Maximum Power Point Tracking

NASA Astrophysics Data System (ADS)

Tokushima, Daiki; Uchida, Masato; Kanbei, Satoshi; Ishikawa, Hiroki; Naitoh, Haruo

This paper presents a new maximum power point tracking control for photovoltaic (PV) panels. The control can be categorized into the Perturb and Observe (P & O) method. It utilizes instantaneous voltage ripples at PV panel output terminals caused by the switching of a chopper connected to the panel in order to identify the direction for the maximum power point (MPP). The tracking for the MPP is achieved by a feedback control of the average terminal voltage of the panel. Appropriate use of the instantaneous and the average values of the PV voltage for the separate purposes enables both the quick transient response and the good convergence with almost no ripples simultaneously. The tracking capability is verified experimentally with a 2.8 W PV panel under a controlled experimental setup. A numerical comparison with a conventional P & O confirms that the proposed control extracts much more power from the PV panel.

Scalable fabrication of perovskite solar cells

DOE PAGES

Li, Zhen; Klein, Talysa R.; Kim, Dong Hoe; ...

2018-03-27

Perovskite materials use earth-abundant elements, have low formation energies for deposition and are compatible with roll-to-roll and other high-volume manufacturing techniques. These features make perovskite solar cells (PSCs) suitable for terawatt-scale energy production with low production costs and low capital expenditure. Demonstrations of performance comparable to that of other thin-film photovoltaics (PVs) and improvements in laboratory-scale cell stability have recently made scale up of this PV technology an intense area of research focus. Here, we review recent progress and challenges in scaling up PSCs and related efforts to enable the terawatt-scale manufacturing and deployment of this PV technology. We discussmore » common device and module architectures, scalable deposition methods and progress in the scalable deposition of perovskite and charge-transport layers. We also provide an overview of device and module stability, module-level characterization techniques and techno-economic analyses of perovskite PV modules.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Zhen; Klein, Talysa R.; Kim, Dong Hoe

Perovskite materials use earth-abundant elements, have low formation energies for deposition and are compatible with roll-to-roll and other high-volume manufacturing techniques. These features make perovskite solar cells (PSCs) suitable for terawatt-scale energy production with low production costs and low capital expenditure. Demonstrations of performance comparable to that of other thin-film photovoltaics (PVs) and improvements in laboratory-scale cell stability have recently made scale up of this PV technology an intense area of research focus. Here, we review recent progress and challenges in scaling up PSCs and related efforts to enable the terawatt-scale manufacturing and deployment of this PV technology. We discussmore » common device and module architectures, scalable deposition methods and progress in the scalable deposition of perovskite and charge-transport layers. We also provide an overview of device and module stability, module-level characterization techniques and techno-economic analyses of perovskite PV modules.« less

Determination of optimum mounting configurations for flat-plate photovoltaic modules based on a structured field experiment and simulated results from PVFORM, a photovoltaic system performance model

NASA Astrophysics Data System (ADS)

Menicucci, D. F.

1986-01-01

The performance of a photovoltaic (PV) system is affected by its mounting configuration. The optimal configuration is unclear because of lack of experience and data. Sandia National Laboratories, Albuquerque (SNLA), has conducted a controlled field experiment to compare four types of the most common module mounting. The data from the experiment were used to verify the accuracy of PVFORM, a new computer program that simulates PV performance. PVFORM was then used to simulate the performance of identical PV modules on different mounting configurations at 10 sites throughout the US. This report describes the module mounting configurations, the experimental methods used, the specialized statistical techniques used in the analysis, and the final results of the effort. The module mounting configurations are rank ordered at each site according to their annual and seasonal energy production performance, and each is briefly discussed in terms of its advantages and disadvantages in various applications.

Effects of synchronous irradiance monitoring and correction of current-voltage curves on the outdoor performance measurements of photovoltaic modules

NASA Astrophysics Data System (ADS)

Hishikawa, Yoshihiro; Doi, Takuya; Higa, Michiya; Ohshima, Hironori; Takenouchi, Takakazu; Yamagoe, Kengo

2017-08-01

Precise outdoor measurement of the current-voltage (I-V) curves of photovoltaic (PV) modules is desired for many applications such as low-cost onsite performance measurement, monitoring, and diagnosis. Conventional outdoor measurement technologies have a problem in that their precision is low when the solar irradiance is unstable, hence, limiting the opportunity of precise measurement only on clear sunny days. The purpose of this study is to investigate an outdoor measurement procedure, that can improve both the measurement opportunity and precision. Fast I-V curve measurements within 0.2 s and synchronous measurement of irradiance using a PV module irradiance sensor very effectively improved the precision. A small standard deviation (σ) of the module’s maximum output power (P max) in the range of 0.7-0.9% is demonstrated, based on the basis of a 6 month experiment, that mainly includes partly sunny days and cloudy days, during which the solar irradiance is unstable. The σ was further improved to 0.3-0.5% by correcting the curves for the small variation of irradiance. This indicates that the procedure of this study enables much more reproducible I-V curve measurements than a conventional usual procedure under various climatic conditions. Factors that affect measurement results are discussed, to further improve the precision.

PLL Based Energy Efficient PV System with Fuzzy Logic Based Power Tracker for Smart Grid Applications.

PubMed

Rohini, G; Jamuna, V

This work aims at improving the dynamic performance of the available photovoltaic (PV) system and maximizing the power obtained from it by the use of cascaded converters with intelligent control techniques. Fuzzy logic based maximum power point technique is embedded on the first conversion stage to obtain the maximum power from the available PV array. The cascading of second converter is needed to maintain the terminal voltage at grid potential. The soft-switching region of three-stage converter is increased with the proposed phase-locked loop based control strategy. The proposed strategy leads to reduction in the ripple content, rating of components, and switching losses. The PV array is mathematically modeled and the system is simulated and the results are analyzed. The performance of the system is compared with the existing maximum power point tracking algorithms. The authors have endeavored to accomplish maximum power and improved reliability for the same insolation of the PV system. Hardware results of the system are also discussed to prove the validity of the simulation results.

PLL Based Energy Efficient PV System with Fuzzy Logic Based Power Tracker for Smart Grid Applications

PubMed Central

Rohini, G.; Jamuna, V.

2016-01-01

This work aims at improving the dynamic performance of the available photovoltaic (PV) system and maximizing the power obtained from it by the use of cascaded converters with intelligent control techniques. Fuzzy logic based maximum power point technique is embedded on the first conversion stage to obtain the maximum power from the available PV array. The cascading of second converter is needed to maintain the terminal voltage at grid potential. The soft-switching region of three-stage converter is increased with the proposed phase-locked loop based control strategy. The proposed strategy leads to reduction in the ripple content, rating of components, and switching losses. The PV array is mathematically modeled and the system is simulated and the results are analyzed. The performance of the system is compared with the existing maximum power point tracking algorithms. The authors have endeavored to accomplish maximum power and improved reliability for the same insolation of the PV system. Hardware results of the system are also discussed to prove the validity of the simulation results. PMID:27294189

Impact of the 4 April 2014 Saharan dust outbreak on the photovoltaic power generation in Germany

NASA Astrophysics Data System (ADS)

Rieger, Daniel; Steiner, Andrea; Bachmann, Vanessa; Gasch, Philipp; Förstner, Jochen; Deetz, Konrad; Vogel, Bernhard; Vogel, Heike

2017-11-01

The importance for reliable forecasts of incoming solar radiation is growing rapidly, especially for those countries with an increasing share in photovoltaic (PV) power production. The reliability of solar radiation forecasts depends mainly on the representation of clouds and aerosol particles absorbing and scattering radiation. Especially under extreme aerosol conditions, numerical weather prediction has a systematic bias in the solar radiation forecast. This is caused by the design of numerical weather prediction models, which typically account for the direct impact of aerosol particles on radiation using climatological mean values and the impact on cloud formation assuming spatially and temporally homogeneous aerosol concentrations. These model deficiencies in turn can lead to significant economic losses under extreme aerosol conditions. For Germany, Saharan dust outbreaks occurring 5 to 15 times per year for several days each are prominent examples for conditions, under which numerical weather prediction struggles to forecast solar radiation adequately. We investigate the impact of mineral dust on the PV-power generation during a Saharan dust outbreak over Germany on 4 April 2014 using ICON-ART, which is the current German numerical weather prediction model extended by modules accounting for trace substances and related feedback processes. We find an overall improvement of the PV-power forecast for 65 % of the pyranometer stations in Germany. Of the nine stations with very high differences between forecast and measurement, eight stations show an improvement. Furthermore, we quantify the direct radiative effects and indirect radiative effects of mineral dust. For our study, direct effects account for 64 %, indirect effects for 20 % and synergistic interaction effects for 16 % of the differences between the forecast including mineral dust radiative effects and the forecast neglecting mineral dust.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barbose, Galen; Wiser, Ryan; Bolinger, Mark

Some stakeholders continue to voice concerns about the performance of customer-sited photovoltaic (PV) systems, particularly because these systems typically receive financial support through ratepayer- or publicly-funded programs. Although much remains to be understood about the extent and specific causes of poor PV system performance, several studies of the larger programs and markets have shed some light on the issue. An evaluation of the California Energy Commission (CEC)'s Emerging Renewables Program, for example, found that 7% of systems, in a sample of 95, had lower-than-expected power output due to shading or soiling (KEMA 2005). About 3% of a larger sample ofmore » 140 systems were not operating at all or were operating well below expected output, due to failed equipment, faulty installation workmanship, and/or a lack of basic maintenance. In a recent evaluation of the other statewide PV incentive program in California, the Self-Generation Incentive Program, 9 of 52 projects sampled were found to have annual capacity factors less than 14.5%, although reasons for these low capacity factors generally were not identified (Itron 2005). Studies of PV systems in Germany and Japan, the two largest PV markets worldwide, have also revealed some performance problems associated with issues such as shading, equipment and installation defects, inverter failure, and deviations from module manufacturers' specifications (Otani et al. 2004, Jahn & Nasse 2004). Although owners of PV systems have an inherent incentive to ensure that their systems perform well, many homeowners and building operators may lack the necessary information and expertise to carry out this task effectively. Given this barrier, and the responsibility of PV incentive programs to ensure that public funds are prudently spent, these programs should (and often do) play a critical role in promoting PV system performance. Performance-based incentives (PBIs), which are based on actual energy production rather than the rated capacity of the modules or system, are often suggested as one possible strategy. Somewhat less recognized are the many other program design options also available, each with its particular advantages and disadvantages. To provide a point of reference for assessing the current state of the art, and to inform program design efforts going forward, we examine the approaches to encouraging PV system performance - including, but not limited to, PBIs - used by 32 prominent PV incentive programs in the U.S. (see Table 1).1 We focus specifically on programs that offer an explicit subsidy payment for customer-sited PV installations. PV support programs that offer other forms of financial support or that function primarily as a mechanism for purchasing renewable energy credits (RECs) through energy production-based payments are outside the scope of our review.2 The information presented herein is derived primarily from publicly available sources, including program websites and guidebooks, programs evaluations, and conference papers, as well as from a limited number of personal communications with program staff. The remainder of this report is organized as follows. The next section presents a simple conceptual framework for understanding the issues that affect PV system performance and provides an overview of the eight general strategies to encourage performance used among the programs reviewed in this report. The subsequent eight sections discuss in greater detail each of these program design strategies and describe how they have been implemented among the programs surveyed. Based on this review, we then offer a series of recommendations for how PV incentive programs can effectively promote PV system performance.« less

Field trial of rural solar photovoltaic system

NASA Astrophysics Data System (ADS)

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.

Radiative Effects of Atmospheric Aerosols and Impacts on Solar Photovoltaic Electricity Generation

NASA Astrophysics Data System (ADS)

Lund, Cory Christopher

Atmospheric aerosols, by scattering and absorbing radiation, perturbs the Earth's energy balance and reduces the amount of insolation reaching the surface. This dissertation first studies the radiative effects of aerosols by analyzing the internal mixing of various aerosol species. It then examines the aerosol impact on solar PV efficiency and the resulting influence on power systems, including both atmospheric aerosols and deposition of particulate matter (PM) on PV surfaces,. Chapter 2 studies the radiative effects of black carbon (BC), sulfate and organic carbon (OC) internal mixing using a simple radiative transfer model. I find that internal mixing may not result in a positive radiative forcing compared to external mixing, but blocks additional shortwave radiation from the surface, enhancing the surface dimming effect. Chapter 3 estimates the impact of atmospheric aerosol attenuation on solar PV resources in China using a PV performance model with satellite-derived long-term surface irradiance data. I find that, in Eastern China, annual average reductions of solar resources due to aerosols are more than 20%, with comparable impacts to clouds in winter. Improving air quality in China would increase efficiency of solar PV generation. As a positive feedback, increased PV efficiency and deployment would further reduce air pollutant emissions too. Chapter 4 further quantifies the total aerosol impact on PV efficiency globally, including both atmospheric aerosols and the deposition of PM on PV surfaces. I find that, if panels are uncleaned and soiling is only removed by precipitation, deposition of PM accounts for more than two-thirds of the total aerosol impact in most regions. Cleaning the panels, even every few months, would largely increase PV efficiency in resource-abundant regions. Chapter 5 takes a further step to evaluate the impact of PV generation reduction due to aerosols on a projected 2030 power system in China with 400GW of PV. I find that aerosols reduce PV generation by 22% and increase baseload power generation, with almost no additional capacity needed. Due to intermittency of solar generation, 160 GW of backup power is needed to maintain grid stability. However, storage provides an opportunity to reduce the backup power capacity by 66%.

City and County Solar PV Training Program, Module 1: Goal Setting and Clarification

DOE Office of Scientific and Technical Information (OSTI.GOV)

McLaren, Joyce A.

This module will help attendees understand nuances between different types of renewable energy goals, the importance of terminology when setting and announcing goals, the value of formally clarifying priorities, and how priorities may impact procurement options. It is the first training in a series intended to help municipal staff procure solar PV for their land and buildings.

Innovation in Photovoltaic Science, Engineering, and Policy: A Potential Trillion-Dollar Global Industry for Sustainable Energy

NASA Astrophysics Data System (ADS)

Zheng, Cheng

The solar photovoltaic (PV) technology was an expensive niche energy source only for satellite applications, hallmarked by the Bell Lab's launch of the Telstar satellite with PV cells in 1962. Over the past decades, the accumulation of vast amount of effort across various disciplines in science, engineering, and policy has enabled the phenomenal growth of the solar PV industry into a global enterprise with about 140 gigawatt (GW) of cumulative installations by the end of 2013. Further cost reduction through innovation holds the promise in deploying terawatt (TW)-scale solar PV systems globally in both developed and developing countries, meeting growing energy demand and mitigating climate change. Chapter 1 presents a big picture view of the unsustainable path, heavily relying on fossil fuels, in the current global energy landscape. The main body of the dissertation examines the solar PV technology from a holistic and interdisciplinary perspective: from the basic research, to innovations in manufacturing and installing PV modules, to the driving energy policies. Chapter 2 offers a fundamental understanding of the PV technology and a review on recent scientific advances in improving PV efficiency (W/m 2). Chapter 3 reviews the state-of-the-art process flow in manufacturing commercial PV modules. In the context of pursuing further reduction in manufacturing cost (/m2), the thin Si film concept and its recent research effort are reviewed. Aiming to explore novel ways to produce high-quality seed crystals for thin Si film deposition, the key findings of the laser crystallization experiment is presented in Chapter 4. The fundamental thermophysics of nucleation and crystal growth is first reviewed, which highlights the importance of temperature evolution and heat transport in modelling the ultrafast laser crystallization process. Laser crystallization of a range of Si nanostructures are then carried out to study the nucleation and crystal growth behavior under some novel conditions, such as suspended narrow Si membranes and Si nanoparticles confined on top of oxide nanostructures. The cost of a PV module (/W) is determined by both its rated efficiency (W/m2) and its manufacturing cost (/m2). However, the same PV module with the same cost can lead to significantly different levelized cost of electricity (LCOE) in /kWh, depending on the location and configuration of the installed PV system. Chapter 5 starts with an overview of the geographic distribution of solar resources and retail electricity rates, which yield a range of grid parity points across the world. Then, energy yield simulations for different PV panel tilt configurations are carried out using the angle-and-wavelength-resolved solar irradiance data, to examine the effect of angular and spectral variations in the solar spectrum on system performance. Energy policies have been the driving forces for the phenomenal progress of the PV technology: the continuing reduction in cost and the rapid growth in deployment. Chapter 6 first reviews major policy instruments for PV, and then discusses about a few important policy lessons from the rapid development of the global PV industry during 2000-2013. Concerned with the mounting fiscal pressure from deployment incentives and focused on further cost reductions, an innovation-focused policy framework is proposed to revive the PV manufacturing sector and to pursue an innovation-driven global PV industry moving forward.

Solar Photovoltaic (PV) Distributed Generation Systems - Control and Protection

NASA Astrophysics Data System (ADS)

Yi, Zhehan

This dissertation proposes a comprehensive control, power management, and fault detection strategy for solar photovoltaic (PV) distribution generations. Battery storages are typically employed in PV systems to mitigate the power fluctuation caused by unstable solar irradiance. With AC and DC loads, a PV-battery system can be treated as a hybrid microgrid which contains both DC and AC power resources and buses. In this thesis, a control power and management system (CAPMS) for PV-battery hybrid microgrid is proposed, which provides 1) the DC and AC bus voltage and AC frequency regulating scheme and controllers designed to track set points; 2) a power flow management strategy in the hybrid microgrid to achieve system generation and demand balance in both grid-connected and islanded modes; 3) smooth transition control during grid reconnection by frequency and phase synchronization control between the main grid and microgrid. Due to the increasing demands for PV power, scales of PV systems are getting larger and fault detection in PV arrays becomes challenging. High-impedance faults, low-mismatch faults, and faults occurred in low irradiance conditions tend to be hidden due to low fault currents, particularly, when a PV maximum power point tracking (MPPT) algorithm is in-service. If remain undetected, these faults can considerably lower the output energy of solar systems, damage the panels, and potentially cause fire hazards. In this dissertation, fault detection challenges in PV arrays are analyzed in depth, considering the crossing relations among the characteristics of PV, interactions with MPPT algorithms, and the nature of solar irradiance. Two fault detection schemes are then designed as attempts to address these technical issues, which detect faults inside PV arrays accurately even under challenging circumstances, e.g., faults in low irradiance conditions or high-impedance faults. Taking advantage of multi-resolution signal decomposition (MSD), a powerful signal processing technique based on discrete wavelet transformation (DWT), the first attempt is devised, which extracts the features of both line-to-line (L-L) and line-to-ground (L-G) faults and employs a fuzzy inference system (FIS) for the decision-making stage of fault detection. This scheme is then improved as the second attempt by further studying the system's behaviors during L-L faults, extracting more efficient fault features, and devising a more advanced decision-making stage: the two-stage support vector machine (SVM). For the first time, the two-stage SVM method is proposed in this dissertation to detect L-L faults in PV system with satisfactory accuracies. Numerous simulation and experimental case studies are carried out to verify the proposed control and protection strategies. Simulation environment is set up using the PSCAD/EMTDC and Matlab/Simulink software packages. Experimental case studies are conducted in a PV-battery hybrid microgrid using the dSPACE real-time controller to demonstrate the ease of hardware implementation and the controller performance. Another small-scale grid-connected PV system is set up to verify both fault detection algorithms which demonstrate promising performances and fault detecting accuracies.

Photovoltaic stand-alone modular systems, phase 2

NASA Technical Reports Server (NTRS)

Naff, G. J.; Marshall, N. A.

1983-01-01

The final hardware and system qualification phase of a two part stand-alone photovoltaic (PV) system development is covered. The final design incorporated modular, power blocks capable of expanding incrementally from 320 watts to twenty kilowatts (PK). The basic power unit (PU) was nominally rated 1.28 kWp. The controls units, power collection buses and main lugs, electrical protection subsystems, power switching, and load management circuits are housed in a common control enclosure. Photo-voltaic modules are electrically connected in a horizontal daisy-chain method via Amp Solarlok plugs mating with compatible connectors installed on the back side of each photovoltaic module. A pair of channel rails accommodate the mounting of the modules into a frameless panel support structure. Foundations are of a unique planter (tub-like) configuration to allow for world-wide deployment without restriction as to types of soil. One battery string capable of supplying approximately 240 ampere hours nominal of carryover power is specified for each basic power unit. Load prioritization and shedding circuits are included to protect critical loads and selectively shed and defer lower priority or noncritical power demands. The baseline system, operating at approximately 2 1/2 PUs (3.2 kW pk.) was installed and deployed. Qualification was successfully complete in March 1983; since that time, the demonstration system has logged approximately 3000 hours of continuous operation under load without major incident.

Photovoltaic stand-alone modular systems, phase 2

NASA Astrophysics Data System (ADS)

Naff, G. J.; Marshall, N. A.

1983-07-01

The final hardware and system qualification phase of a two part stand-alone photovoltaic (PV) system development is covered. The final design incorporated modular, power blocks capable of expanding incrementally from 320 watts to twenty kilowatts (PK). The basic power unit (PU) was nominally rated 1.28 kWp. The controls units, power collection buses and main lugs, electrical protection subsystems, power switching, and load management circuits are housed in a common control enclosure. Photo-voltaic modules are electrically connected in a horizontal daisy-chain method via Amp Solarlok plugs mating with compatible connectors installed on the back side of each photovoltaic module. A pair of channel rails accommodate the mounting of the modules into a frameless panel support structure. Foundations are of a unique planter (tub-like) configuration to allow for world-wide deployment without restriction as to types of soil. One battery string capable of supplying approximately 240 ampere hours nominal of carryover power is specified for each basic power unit. Load prioritization and shedding circuits are included to protect critical loads and selectively shed and defer lower priority or noncritical power demands. The baseline system, operating at approximately 2 1/2 PUs (3.2 kW pk.) was installed and deployed. Qualification was successfully complete in March 1983; since that time, the demonstration system has logged approximately 3000 hours of continuous operation under load without major incident.

Solar Electric System

NASA Technical Reports Server (NTRS)

1987-01-01

Heat Pipe Technology, Inc. undertook the development of a PV system that could bring solar electricity to the individual home at reasonable cost. His system employs high efficiency PV modules plus a set of polished reflectors that concentrate the solar energy and enhance the output of the modules. Dinh incorporated a sun tracking system derived from space tracking technology. It automatically follows the sun throughout the day and turns the modules so that they get maximum exposure to the solar radiation, further enhancing the system efficiency.

Outdoor Test Facility and Related Facilities | Photovoltaic Research | NREL

Science.gov Websites

advanced or emerging photovoltaic (PV) technologies under simulated, accelerated indoor and outdoor, and evaluate prototype, pre-commercial, and commercial PV modules. One of the major roles of researchers at the OTF is to work with industry to develop uniform and consensus standards and codes for testing PV

Sub-synchronous resonance damping using high penetration PV plant

NASA Astrophysics Data System (ADS)

Khayyatzadeh, M.; Kazemzadeh, R.

2017-02-01

The growing need to the clean and renewable energy has led to the fast development of transmission voltage-level photovoltaic (PV) plants all over the world. These large scale PV plants are going to be connected to power systems and one of the important subjects that should be investigated is the impact of these plants on the power system stability. Can large scale PV plants help to damp sub-synchronous resonance (SSR) and how? In this paper, this capability of a large scale PV plant is investigated. The IEEE Second Benchmark Model aggregated with a PV plant is utilized as the case study. A Wide Area Measurement System (WAMS) based conventional damping controller is designed and added to the main control loop of PV plant in order to damp the SSR and also investigation of the destructive effect of time delay in remote feedback signal. A new optimization algorithm called teaching-learning-based-optimization (TLBO) algorithm has been used for managing the optimization problems. Fast Furrier Transformer (FFT) analysis and also transient simulations of detailed nonlinear system are considered to investigate the performance of the controller. Robustness of the proposed system has been analyzed by facing the system with disturbances leading to significant changes in generator and power system operating point, fault duration time and PV plant generated power. All the simulations are carried out in MATLAB/SIMULINK environment.

Photovoltaics program plan, FY 1991 - 1995

NASA Astrophysics Data System (ADS)

1991-10-01

This program plan describes the goals and philosophy of DOE National Photovoltaics Program and its major research and development activities for fiscal years (FY) 1991 through 1995. The plan represents a consensus among researchers and manufacturers, as well as current and potential users of photovoltaics (PV). It defines the activities that we believe are necessary to continue the rapid progress toward acceptance of photovoltaics as a serious candidate for cost-competitive electric power generation by the utility, transportation, buildings, and industrial sectors. A successful National Photovoltaics Program will help achieve many of our national priorities. The mission of the National Photovoltaics Program is to help US industry to develop photovoltaic technology for large-scale generation of economically competitive electric power in the United States, making PV a significant part of our national energy mix. To fully achieve this, we must continue to work toward the long-term goals established in our previous program plan: reducing the price of delivered electricity to 5 to 6 cents per kilowatt-hour (kWh), increasing lifetimes to 30 years, and increasing module efficiencies to 15 percent for flat-plate and 25 percent for concentrator technologies. If progress continues at its current pace, we expect that the PV industry will have installed at least 1000 megawatts (MW) of capacity in the United States and 500 MW internationally by the year 2000.

New Markets for Solar Photovoltaic Power Systems

NASA Astrophysics Data System (ADS)

Thomas, Chacko; Jennings, Philip; Singh, Dilawar

2007-10-01

Over the past five years solar photovoltaic (PV) power supply systems have matured and are now being deployed on a much larger scale. The traditional small-scale remote area power supply systems are still important and village electrification is also a large and growing market but large scale, grid-connected systems and building integrated systems are now being deployed in many countries. This growth has been aided by imaginative government policies in several countries and the overall result is a growth rate of over 40% per annum in the sales of PV systems. Optimistic forecasts are being made about the future of PV power as a major source of sustainable energy. Plans are now being formulated by the IEA for very large-scale PV installations of more than 100 MW peak output. The Australian Government has announced a subsidy for a large solar photovoltaic power station of 154 MW in Victoria, based on the concentrator technology developed in Australia. In Western Australia a proposal has been submitted to the State Government for a 2 MW photovoltaic power system to provide fringe of grid support at Perenjori. This paper outlines the technologies, designs, management and policies that underpin these exciting developments in solar PV power.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wohlgemuth, J.

Description and history of the IEC 61215 qualification test, what it accomplishes, and what it does not accomplish that would be useful to the community. The commercial success of PV is based on long term reliability of the PV modules. Today's modules are typically qualified/certified to: (1) IEC 61215 for Crystalline Silicon Modules; (2) IEC 61646 for Thin Film Modules; and (3) IEC 62108 for CPV Modules. These qualification tests do an excellent job of identifying design, materials and process flaws that could lead to premature field failures. This talk will provide a summary of how IEC 61215 was developed,more » how well it works and what its limitations are.« less

A new maximum power tracking in PV system during partially shaded conditions based on shuffled frog leap algorithm

NASA Astrophysics Data System (ADS)

Sridhar, R.; Jeevananthan, S.; Dash, S. S.; Vishnuram, Pradeep

2017-05-01

Maximum Power Point Trackers (MPPTs) are power electronic conditioners used in photovoltaic (PV) system to ensure that PV structures feed maximum power for the given ambient temperature and sun's irradiation. When the PV panels are shaded by a fraction due to any environment hindrances then, conventional MPPT trackers may fail in tracking the appropriate peak power as there will be multi power peaks. In this work, a shuffled frog leap algorithm (SFLA) is proposed and it successfully identifies the global maximum power point among other local maxima. The SFLA MPPT is compared with a well-entrenched conventional perturb and observe (P&O) MPPT algorithm and a global search particle swarm optimisation (PSO) MPPT. The simulation results reveal that the proposed algorithm is highly advantageous than P&O, as it tracks nearly 30% more power for a given shading pattern. The credible nature of the proposed SFLA is ensured when it outplays PSO MPPT in convergence. The whole system is realised in MATLAB/Simulink environment.

Synchrotron X-Ray Topography for Encapsulation Stress/Strain and Crack Detection in Crystalline Silicon Modules

DOE PAGES

Colli, Alessandra; Attenkofer, Klaus; Raghothamachar, Balaji; ...

2016-07-14

Here in this article, we present the first experiment to prove the capabilities of X-ray topography for the direct imaging and analysis of defects, stress, and strain affecting the cell within the laminated photovoltaic (PV) module. Cracks originating from grain boundaries structures have been detected, developing along the cleavage planes of the crystal. The strain affecting the cell is clearly visualized through the bending of the metallization line images and can be easily mapped. While the recording conditions need to be optimized to maximize image contrast, this experiment demonstrates how synchrotron facilities can enable PV industry and research to characterizemore » full PV modules. Appropriate development of the technique could also lead to future use of laboratory-level X-ray sources.« less

Photovoltaic materials and devices 2016

DOE PAGES

Sopori, Bhushan; Basnyat, Prakash; Mehta, Vishal

2016-01-01

Photovoltaic energy continues to grow with about 59 GW of solar PV installed in 2015. While most of the PV production (about 93%) was Si wafer based, both CdTe and CI(G)S are growing in their shares. There is also continued progress at the laboratory scale in OPV and dye sensitized solar cells. As the market grows, emphasis on reducing the cost of modules and systems continues to grow. This is the fourth special issue of this journal that is dedicated to gathering selected papers on recent advances in materials, devices, and modules/PV systems. This issue contains sixteen papers on variousmore » aspects of photovoltaics. As a result, these fall in four broad categories of novel materials, device design and fabrication, modules, and systems.« less

NREL at 40: It All Started With a Desire to Harness the Sun | News | NREL

Science.gov Websites

(PV) industry. Their job was to ultimately develop new solar technology and to chart a path toward its of reliability for PV modules and systems, helping bolster consumer and investor confidence in solar With a Desire to Harness the Sun July 5, 2017 Photo of PV panels under a bright blue sky. A PV array on

Smoothing PV System’s Output by Tuning MPPT Control

NASA Astrophysics Data System (ADS)

Ina, Nobuhiko; Yanagawa, Shigeyuki; Kato, Takeyoshi; Suzuoki, Yasuo

A PV system’s output is not stable and fluctuates depending on a weather condition. Using a battery is one of the feasible ways to stabilize a PV system’s output, although it requires an additional cost and provides an additional waste of the used battery. In this paper, we propose tuning a characteristic of Maxiumum Power Point Tracking (MPPT) control for smoothing a short term change of PV system’s output during a sharp insolation fluctuation, as an approach without additional equipments. In our proposed method, when an insolation increases rapidly, the operation point of MPPT control changes to the new point where the maximum power is not generated with present insolation, so that the speed of PV system’s output increase is limited to a certain value, i. e. 1%/min. In order to evaluate the effect of our proposed method in terms of reducing the additional operation task of the electric power system, we evaluated the additional LFC capacity for a large-scale installation of PV systems. As a result, it was revealed that the additional LFC capacity is not required even if a PV system is installed by 5% of utility system, when our proposed method is applied to all PV systems.

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

NASA Technical Reports Server (NTRS)

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

2015-01-01

CubeSats, Communication Satellites, and Outer Planet Science Satellites all share one thing in common: Mission success depends on maintaining power in the harsh space environment. For a vast majority of satellites, spacecraft power is sourced by a photovoltaic (PV) array system. Built around PV cells, the array systems also include wiring, substrates, connectors, and protection diodes. Each of these components must function properly throughout the mission in order for power production to remain at nominal levels. Failure of even one component can lead to a crippling loss of power. To help ensure PV array systems do not suffer failures on-orbit due to the space environment, NASA's Marshall Space Flight Center (MSFC) has developed a wide ranging test and evaluation capability. Key elements of this capability include: Testing: a. Ultraviolet (UV) Exposure b. Charged Particle Radiation (Electron and Proton) c. Thermal Cycling d. Plasma and Beam Environments Evaluation: a. Electrostatic Discharge (ESD) Screening b. Optical Inspection and easurement c. PV Power Output including Large Area Pulsed Solar Simulator (LAPSS) measurements This paper will describe the elements of the space environment which particularly impact PV array systems. MSFC test capabilities will be described to show how the relevant space environments can be applied to PV array systems in the laboratory. A discussion of MSFC evaluation capabilities will also be provided. The sample evaluation capabilities offer test engineers a means to quantify the effects of the space environment on their PV array system or component. Finally, examples will be shown of the effects of the space environment on actual PV array materials tested at MSFC.

Photovoltaics Innovation Roadmap Request for Information Summary

DOE Office of Scientific and Technical Information (OSTI.GOV)

None, None

On June 28, 2017, the U.S. Department of Energy’s Solar Energy Technologies Office (SETO) released the Photovoltaics (PV) Innovation Roadmap Request for Information (RFI) for public response and comment. The RFI sought feedback from PV stakeholders, including research and commercial communities, about the most important research and development (R&D) pathways to improve PV cell and module technology to reach the SETO’s SunShot 2030 cost targets of $0.03/W for utility PV installations, $0.04/W for commercial scale installations, and $0.05/W for residential PV installations.

Can solar power deliver?

PubMed

Nelson, Jenny; Emmott, Christopher J M

2013-08-13

Solar power represents a vast resource which could, in principle, meet the world's needs for clean power generation. Recent growth in the use of photovoltaic (PV) technology has demonstrated the potential of solar power to deliver on a large scale. Whilst the dominant PV technology is based on crystalline silicon, a wide variety of alternative PV materials and device concepts have been explored in an attempt to decrease the cost of the photovoltaic electricity. This article explores the potential for such emerging technologies to deliver cost reductions, scalability of manufacture, rapid carbon mitigation and new science in order to accelerate the uptake of solar power technologies.

Power conditioning unit for photovoltaic power systems

NASA Astrophysics Data System (ADS)

Beghin, G.; Nguyen Phuoc, V. T.

Operational features and components of a power conditioning unit for interconnecting solar cell module powers with a utility grid are outlined. The two-stage unit first modifies the voltage to desired levels on an internal dc link, then inverts the current in 2 power transformers connected to a vector summation control to neutralize harmonic distortion up to the 11th harmonic. The system operates in parallel with the grid with extra inductors to absorb line-to-line voltage and phase differences, and permits peak power use from the PV array. Reactive power is gained internally, and a power system controller monitors voltages, frequencies, and currents. A booster preregulator adjusts the input voltage from the array to provide voltage regulation for the inverter, and can commutate 450 amps. A total harmonic distortion of less than 5 percent is claimed, with a rating of 5 kVA, 50/60 Hz, 3-phase, and 4-wire.

Optimization of a stand-alone Solar PV-Wind-DG Hybrid System for Distributed Power Generation at Sagar Island

NASA Astrophysics Data System (ADS)

Roy, P. C.; Majumder, A.; Chakraborty, N.

2010-10-01

An estimation of a stand-alone solar PV and wind hybrid system for distributed power generation has been made based on the resources available at Sagar island, a remote area distant to grid operation. Optimization and sensitivity analysis has been made to evaluate the feasibility and size of the power generation unit. A comparison of the different modes of hybrid system has been studied. It has been estimated that Solar PV-Wind-DG hybrid system provides lesser per unit electricity cost. Capital investment is observed to be lesser when the system run with Wind-DG compared to Solar PV-DG.

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

NASA Astrophysics Data System (ADS)

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.

Capital intensity of photovoltaics manufacturing: Barrier to scale and opportunity for innovation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Powell, Douglas M.; Fu, Ran; Horowitz, Kelsey

In this study, using a bottom-up cost model, we assess the impact of initial factory capital expenditure (capex) on photovoltaic (PV) module minimum sustainable price (MSP) and industry-wide trends. We find capex to have two important impacts on PV manufacturing. First, capex strongly influences the per-unit MSP of a c-Si module: we calculate that the capex-related elements sum to 22% of MSP for an integrated wafer, cell, and module manufacturer. This fraction provides a significant opportunity to reduce MSP toward the U.S. DOE SunShot module price target through capex innovation.

Capital intensity of photovoltaics manufacturing: Barrier to scale and opportunity for innovation

DOE PAGES

Powell, Douglas M.; Fu, Ran; Horowitz, Kelsey; ...

2015-09-07

In this study, using a bottom-up cost model, we assess the impact of initial factory capital expenditure (capex) on photovoltaic (PV) module minimum sustainable price (MSP) and industry-wide trends. We find capex to have two important impacts on PV manufacturing. First, capex strongly influences the per-unit MSP of a c-Si module: we calculate that the capex-related elements sum to 22% of MSP for an integrated wafer, cell, and module manufacturer. This fraction provides a significant opportunity to reduce MSP toward the U.S. DOE SunShot module price target through capex innovation.

The capacity credit of grid-connected photovoltaic systems

NASA Astrophysics Data System (ADS)

Alsema, E. A.; van Wijk, A. J. M.; Turkenburg, W. C.

The capacity credit due photovoltaic (PV) power plants if integrated into the Netherlands grid was investigated, together with an estimate of the total allowable penetration. An hourly simulation was performed based on meteorological data from five stations and considering tilted surfaces, the current grid load pattern, and the load pattern after PV-power augmentation. The reliability of the grid was assessed in terms of a loss of load probability analysis, assuming power drops were limited to 1 GW. A projected tolerance for 2.5 GW of PV power was calculated. Peak demands were determined to be highest in winter, contrary to highest insolation levels; however, daily insolation levels coincided with daily peak demands. Combining the PV input with an equal amount of wind turbine power production was found to augment the capacity credit for both at aggregate outputs of 2-4 GW.

New York Solar Smart DG Hub-Resilient Solar Project: Economic and Resiliency Impact of PV and Storage on New York Critical Infrastructure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, Kate; Burman, Kari; Simpkins, Travis

Resilient PV, which is solar paired with storage ('solar-plus-storage'), provides value both during normal grid operation and power outages as opposed to traditional solar PV, which functions only when the electric grid is operating. During normal grid operations, resilient PV systems help host sites generate revenue and/or reduce electricity bill charges. During grid outages, resilient PV provides critical emergency power that can help people in need and ease demand on emergency fuel supplies. The combination of grid interruptions during recent storms, the proliferation of solar PV, and the growing deployment of battery storage technologies has generated significant interest in usingmore » these assets for both economic and resiliency benefits. This report analyzes the technical and economic viability for resilient PV on three critical infrastructure sites in New York City (NYC): a school that is part of a coastal storm shelter system, a fire station, and a NYCHA senior center that serves as a cooling center during heat emergencies. This analysis differs from previous solar-plus-storage studies by placing a monetary value on resiliency and thus, in essence, modeling a new revenue stream for the avoided cost of a power outage. Analysis results show that resilient PV is economically viable for NYC's critical infrastructure and that it may be similarly beneficial to other commercial buildings across the city. This report will help city building owners, managers, and policymakers better understand the economic and resiliency benefits of resilient PV. As NYC fortifies its building stock against future storms of increasing severity, resilient PV can play an important role in disaster response and recovery while also supporting city greenhouse gas emission reduction targets and relieving stress to the electric grid from growing power demands.« less

Description and status of NASA-LeRC/DOE photovoltaic applications systems experiments

NASA Technical Reports Server (NTRS)

Ratajczak, A. F.

1978-01-01

In its role of supporting the DOE Photovoltaic Program, the NASA-Lewis Research Center has designed, fabricated and installed 16 geographically dispersed photovoltaic systems. These systems are powering a refrigerator, highway warning sign, forest lookout towers, remote weather stations, a water chiller at a visitor center, and insect survey traps. Each of these systems is described in terms of load requirements, solar array and battery size, and instrumentation and controls. Operational experience is described and present status is given for each system. The P/V power systems have proven to be highly reliable with almost no problems with modules and very few problems overall

The Photovoltaic Higher Education National Exemplar Facility (PHENEF)

NASA Astrophysics Data System (ADS)

Podbielski, V.; Shaff, D.

1994-04-01

In August 1980, the US Department of Energy awarded the proposed grant to Georgetown University. The grant covered the following tasks: Task 1, The Department of Energy would participate in the building of an academic facility that would facilitate the integration of flat plate photovoltaic roof modules with an optimally oriented solar architecture. The completion of the facility to be built on the Georgetown University Campus and known as the Georgetown University Intercultural Center was to be a jointly funded endeavor with the Department of Education funding $9.2M through a grant and a loan, Department of Energy funding a maximum of $4M and Georgetown University funding the residual costs. Task 2, Georgetown University would provide the necessary skills, services, materials, equipment and facilities to design, furnish, install and make operational the Georgetown University Intercultural Center Photovoltaic System. The specific objective of this effort would be to build an exemplar flat plate electrical grid connected photovoltaic (PV) system which would demonstrate integration of PV modules into a watertight roofing surface. The system capability, measured at the input to the inverter, would be a 300 kilowatt peak power system as measured at the normal cell operating temperature and an isolation of 100 milliwatts per square centimeter at the collector surface. DOE funding under the grant for the PV system would be limited to a system cost of $20.00 per peak watt up to maximum of six million dollars.

Technology advances needed for photovoltaics to achieve widespread grid price parity: Widespread grid price parity for photovoltaics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones-Albertus, Rebecca; Feldman, David; Fu, Ran

2016-04-20

To quantify the potential value of technological advances to the photovoltaics (PV) sector, this paper examines the impact of changes to key PV module and system parameters on the levelized cost of energy (LCOE). The parameters selected include module manufacturing cost, efficiency, degradation rate, and service lifetime. NREL's System Advisor Model (SAM) is used to calculate the lifecycle cost per kilowatt-hour (kWh) for residential, commercial, and utility scale PV systems within the contiguous United States, with a focus on utility scale. Different technological pathways are illustrated that may achieve the Department of Energy's SunShot goal of PV electricity that ismore » at grid price parity with conventional electricity sources. In addition, the impacts on the 2015 baseline LCOE due to changes to each parameter are shown. These results may be used to identify research directions with the greatest potential to impact the cost of PV electricity.« less

Abnormal excessive per vagina (PV) bleeding on Esmya–selective progesterone receptor modulator (SPRM) in a symptomatic patient with uterine fibroid

PubMed Central

Matytsina-Quinlan, Lyubov; Matytsina, Laura

2015-01-01

A woman in her late 40s presented with excessive per vagina (PV) bleeding and uterine fibroid. She reported excessive PV bleeding after starting Esmya; she was brought in by ambulance to the emergency department with profuse bleeding. Abnormal uterine bleeding (AUB) developed after selective progesterone receptor modulator (SPRM) administration in this symptomatic patient with uterine fibroid. The drug was withheld and surgical treatment considered. Progressive deterioration of PV bleeding after receiving SPRM led to an urgent laparoscopic total hysterectomy, which had to be postponed due to severe anaemia. Surgery took place regardless because the excessive bleeding continued. Histology revealed a 6 cm submucosal uterine fibroid (SMUF) and adenomyosis. Physicians prescribing SPRMs to stop PV bleeding should be aware of potential AUB, which could lead to urgent hysterectomy. The mechanism of action of SPRMs is not clearly understood. Awareness of the side effects of Esmya, such as AUB, must be kept in mind when administering SPRMs. PMID:25976198

Abnormal excessive per vagina (PV) bleeding on Esmya-selective progesterone receptor modulator (SPRM) in a symptomatic patient with uterine fibroid.

PubMed

Matytsina-Quinlan, Lyubov; Matytsina, Laura

2015-05-14

A woman in her late 40s presented with excessive per vagina (PV) bleeding and uterine fibroid. She reported excessive PV bleeding after starting Esmya; she was brought in by ambulance to the emergency department with profuse bleeding. Abnormal uterine bleeding (AUB) developed after selective progesterone receptor modulator (SPRM) administration in this symptomatic patient with uterine fibroid. The drug was withheld and surgical treatment considered. Progressive deterioration of PV bleeding after receiving SPRM led to an urgent laparoscopic total hysterectomy, which had to be postponed due to severe anaemia. Surgery took place regardless because the excessive bleeding continued. Histology revealed a 6 cm submucosal uterine fibroid (SMUF) and adenomyosis. Physicians prescribing SPRMs to stop PV bleeding should be aware of potential AUB, which could lead to urgent hysterectomy. The mechanism of action of SPRMs is not clearly understood. Awareness of the side effects of Esmya, such as AUB, must be kept in mind when administering SPRMs. 2015 BMJ Publishing Group Ltd.

On the Path to SunShot - Emerging Opportunities and Challenges in U.S. Solar Manufacturing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chung, Donald; Horowitz, Kelsey; Kurup, Parthiv

Innovation-driven cost and performance improvements, along with strong projected solar demand in the United States and across the Americas, could increase the attractiveness of U.S.-based solar manufacturing (see Chung et al. 2016). Although improvements to standard PV modules have produced deep cost reductions over the past 5 years, the returns on such incremental improvements appear to be diminishing, and more dramatic innovations in module design and manufacturing are required to continue along the path of rapid progress. At the same time, major opportunities exist for innovation to unlock the potential of CSP technologies. This need for innovation could benefit U.S.more » PV and CSP manufacturers. The United States has been rated one of the world’s most competitive and innovative countries as well as one of the best locations for PV manufacturing. It is a global leader in PV and CSP R&D and patent production, and U.S. PV manufacturers are already pursuing highly differentiated innovations.« less

Crystal growth and materials research in photovoltaics: progress and challenges

NASA Astrophysics Data System (ADS)

Surek, Thomas

2005-02-01

Photovoltaics (PV) is solar electric power—a semiconductor-based technology that converts sunlight to electricity. Three decades of research has led to the discovery of new materials and devices and new processing techniques for low-cost manufacturing. This has resulted in improved sunlight-to-electricity conversion efficiencies, improved outdoor reliability, and lower module and system costs. The manufacture and sale of PV has grown into a $5 billion industry worldwide, with more than 740 megawatts of PV modules shipped in 2003. This paper reviews the significant progress that has occurred in PV materials and devices research over the past 30 years, focusing on the advances in crystal growth and materials research, and examines the challenges to reaching the ultimate potential of current-generation (crystalline silicon), next-generation (thin films and concentrators), and future-generation PV technologies. The latter includes innovative materials and device concepts that hold the promise of significantly higher conversion efficiencies and/or much lower costs.

Evaluating the effect placement capacitor and distributed photovoltaic generation for power system losses minimization in radial distribution system

NASA Astrophysics Data System (ADS)

Rahman, Yuli Asmi; Manjang, Salama; Yusran, Ilham, Amil Ahmad

2018-03-01

Power loss minimization have many advantagess to the distribution system radial among others reduction of power flow in feeder lines, freeing stress on feeder loading, deterrence of power procurement from the grid and also the cost of loss compensating instruments. This paper, presents capacitor and photovoltaic (PV) placement as alternative means to decrease power system losses. The paper aims to evaluate the best alternative for decreasing power system losses and improving voltage profile in the radial distribution system. To achieve the objectives of paper, they are used three cases tested by Electric Transient and Analysis Program (ETAP) simulation. Firstly, it performs simulation of placement capacitor. Secondly, simulated placement of PV. Lastly, it runs simulation of placement capacitor and PV simultaneously. The simulations were validated using the IEEE 34-bus test system. As a result, they proved that the installation of capacitor and PV integration simultaneously leading to voltage profile correction and power losses minimization significantly.

Inaugural History of the National Center for Photovoltaics | Photovoltaic

Science.gov Websites

technology and disseminating information about photovoltaics (PV) in the United States. When created, the NCPV's long-term goals were for PV modules and systems to reach still higher efficiencies with improved , industry, and other federal programs into a united effort and accelerating the advance of PV as an industry

KSC-00dig067

NASA Image and Video Library

2000-10-31

After repair of a cracked cleat on the crawler-transporter, Space Shuttle Endeavour finally rests on Launch Pad 39B. To the left is the Rotating Service Structure. Endeavour is scheduled to be launched Nov. 30 at 10:01 p.m. EST on mission STS-97, the sixth construction flight to the International Space Station. Its payload includes the P6 Integrated Truss Structure and a photovoltaic (PV) module, with giant solar arrays that will provide power to the Station. The mission includes two spacewalks to complete the solar array connections

KSC-00padig104

NASA Image and Video Library

2000-11-28

STS-97 Mission Specialist Carlos Noriega gets help with his boots from suit technician Shelly Grick-Agrella during pre-pack and fit check. Mission STS-97 is the sixth construction flight to the International Space Station. Its payload includes the P6 Integrated Truss Structure and a photovoltaic (PV) module, with giant solar arrays that will provide power to the Station. The mission includes two spacewalks to complete the solar array connections. STS-97 is scheduled to launch Nov. 30 at about 10:06 p.m. EST

KSC-00padig108

NASA Image and Video Library

2000-11-28

During pre-pack and fit check in the Operations and Checkout Building, STS-97 Commander Brent Jett gets help with his gloves from suit technician Bill Todd. Mission STS-97 is the sixth construction flight to the International Space Station. Its payload includes the P6 Integrated Truss Structure and a photovoltaic (PV) module, with giant solar arrays that will provide power to the Station. The mission includes two spacewalks to complete the solar array connections. STS-97 is scheduled to launch Nov. 30 at about 10:06 p.m. EST

KSC-00padig103

NASA Image and Video Library

2000-11-28

STS-97 Mission Specialist Joseph Tanner gets help with his boots from suit technician Erin Canlon during check pre-pack and fit check. Mission STS-97 is the sixth construction flight to the International Space Station. Its payload includes the P6 Integrated Truss Structure and a photovoltaic (PV) module, with giant solar arrays that will provide power to the Station. The mission includes two spacewalks to complete the solar array connections. STS-97 is scheduled to launch Nov. 30 at about 10:06 p.m. EST

KSC-00padig106

NASA Image and Video Library

2000-11-28

STS-97 Pilot Michael Bloomfield gets help with his boots from suit technician Steve Clendenin during pre-pack and fit check. Mission STS-97 is the sixth construction flight to the International Space Station. Its payload includes the P6 Integrated Truss Structure and a photovoltaic (PV) module, with giant solar arrays that will provide power to the Station. The mission includes two spacewalks to complete the solar array connections. STS-97 is scheduled to launch Nov. 30 at about 10:06 p.m. EST

Availability model of stand-alone photovoltaic system

NASA Astrophysics Data System (ADS)

Mazurek, G.

2017-08-01

In this paper we present a simple, empirical model of stand-alone photovoltaic power system availability. The model is a final result of five-year long studies and ground measurements of solar irradiation carried out in Central Europe. The obtained results facilitate sizing of PV modules that have to be installed with taking into account system's availability level in each month of a year. The model can be extended to different geographical locations, with help of local meteorological data or solar irradiation datasets derived from satellite measurements.

Experimental investigation of solar powered diaphragm and helical pumps

USDA-ARS?s Scientific Manuscript database

For several years, many types of solar powered water pumping systems were evaluated, and in this paper, diaphragm and helical solar photovoltaic (PV) powered water pumping systems are discussed. Data were collected on diaphragm and helical pumps which were powered by different solar PV arrays at mul...

Gelsolin: a novel thyroid hormone receptor-beta interacting protein that modulates tumor progression in a mouse model of follicular thyroid cancer.

PubMed

Kim, Caroline S; Furuya, Fumihiko; Ying, Hao; Kato, Yasuhito; Hanover, John A; Cheng, Sheue-yann

2007-03-01

Follicular thyroid cancer (FTC) is known to metastasize to distant sites via hematogenous spread; however, the underlying pathways that contribute to metastasis remain unknown. Recent creation of a knockin mutant mouse that expresses a mutant thyroid hormone receptor-beta (TRbeta(PV/PV) mouse) that spontaneously develops thyroid cancer with metastasis similar to humans has provided new opportunities to study contributors to FTC metastasis. This study evaluates the role of gelsolin, an actin-regulatory protein, in modulating the metastatic potential of FTC. Gelsolin was previously found by cDNA microarray analysis to be down-regulated in TRbeta(PV/PV) mice as compared with wild-type mice. This study found an age-dependent reduction of gelsolin protein abundance in TRbeta(PV/PV) mice as tumorigenesis progressed. Knockdown of gelsolin by small interfering RNA resulted in increased tumor cell motility and increased gelsolin expression by histone deacetylase inhibitor (trichostatin A) led to decreased cell motility. Additional biochemical analyses demonstrated that gelsolin physically interacted with TRbeta1 or PV in vivo and in vitro. The interaction regions were mapped to the C terminus of gelsolin and the DNA binding domain of TR. The physical interaction of gelsolin with PV reduced its binding to actin, leading to disarrayed cytoskeletal architectures. These results suggest that PV-induced alteration of the actin/gelsolin cytoskeleton contributes to increased cell motility. Thus, the present study uncovered a novel PV-mediated oncogenic pathway that could contribute to the local tumor progression and metastatic potential of thyroid carcinogenesis.

Building Integrated Photovoltaic Module-Based on Aluminum Substrate With Forced Water Cooling.

PubMed

Pang, Wei; Zhang, Yongzhe; Cui, Yanan; Yu, Hongwen; Liu, Yu; Yan, Hui

2018-04-01

The increase of operating temperature on a photovoltaic (PV) cell degrades its electrical efficiency. This paper is organized to describe our latest design of an aluminum substrate-based photovoltaic/thermal (PV/T) system. The electrical efficiency of the proposed PV/T can be increased by ∼ 20% in comparison with a conventional glass substrate-based PV. The work will benefit hybrid utilization of solar energy in development of building integrated photovoltaic systems.

Commercialization of PV-powered pumping systems for use in utility PV service programs. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1997-03-01

The project described in this report was a commercialization effort focused on cost-effective remote water pumping systems for use in utility-based photovoltaic (PV) service programs. The project combined a commercialization strategy tailored specifically for electric utilities with the development of a PV-powered pumping system that operates conventional ac pumps rather than relying on the more expensive and less reliable PV pumps on the market. By combining these two attributes, a project goal was established of creating sustained utility purchases of 250 PV-powered water pumping systems per year. The results of each of these tasks are presented in two parts containedmore » in this Final Summary Report. The first part summarizes the results of the Photovoltaic Services Network (PSN) as a new business venture, while the second part summarizes the results of the Golden Photon system installations. Specifically, results and photographs from each of the system installations are presented in this latter part.« less

Design of energy storage system to improve inertial response for large scale PV generation

DOE PAGES

Wang, Xiaoyu; Yue, Meng

2016-07-01

With high-penetration levels of renewable generating sources being integrated into the existing electric power grid, conventional generators are being replaced and grid inertial response is deteriorating. This technical challenge is more severe with photovoltaic (PV) generation than with wind generation because PV generation systems cannot provide inertial response unless special countermeasures are adopted. To enhance the inertial response, this paper proposes to use battery energy storage systems (BESS) as the remediation approach to accommodate the degrading inertial response when high penetrations of PV generation are integrated into the existing power grid. A sample power system was adopted and simulated usingmore » PSS/E software. Here, impacts of different penetration levels of PV generation on the system inertial response were investigated and then BESS was incorporated to improve the frequency dynamics.« less