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Dye Sensitized Tandem Photovoltaic Cells

Description: This work provided a new way to look at photoelectrochemical cells and their performance. Although thought of as low efficiency, a the internal efficiency of a 9% global efficiency dye sensitized solar cell is approximately equal to an 18% efficient silicon cell when each is compared to their useful spectral range. Other work undertaken with this contract also reported the first growth oriented titania and perovskite columns on a transparent conducting oxide. Other work has shown than significant performance enhancement in the performance of dye sensitized solar cells can be obtained through the use of coupling inverse opal photonic crystals to the nanocrystalline dye sensitized solar cell. Lastly, a quick efficient method was developed to bond titanium foils to transparent conducting oxide substrates for anodization.
Date: December 21, 2009
Creator: Barber, Greg D.
Partner: UNT Libraries Government Documents Department

Wind/PV Generation for Frequency Regulation and Oscillation Damping in the Eastern Interconnection

Description: This report presents the control of renewable energy sources, including the variable-speed wind generators and solar photovoltaic (PV) generators, for frequency regulation and inter-area oscillation damping in the U.S. Eastern Interconnection (EI). In this report, based on the user-defined wind/PV generator electrical control model and the 16,000-bus Eastern Interconnection dynamic model, the additional controllers for frequency regulation and inter-area oscillation damping are developed and incorporated and the potential contributions of renewable energy sources to the EI system frequency regulation and inter-area oscillation damping are evaluated.
Date: December 1, 2013
Creator: Liu, Yong; Gracia, Jose R; Hadley, Stanton W & Liu, Yilu
Partner: UNT Libraries Government Documents Department

Benefits from the US photovoltaic manufacturing technology project

Description: This paper examines the goals of the Photovoltaic Manufacturing Technology (PVMaT) project and its achievements in recapturing the investment by the photovoltaic (PV) industry and the public in this research. The PVMaT project was initiated in 1990 with the goal of enhancing the world-wide competitiveness of the U.S. PV industry. Based on our analysis, PVMaT has contributed to PV module manufacturing process improvements, increased product value, and reductions in the price of today`s PV products. An evaluation of success in this project was conducted using data collected from 10 of the PVMaT industrial participants in late fiscal year (FY) 1995. These data indicate a reduction of 56% in the weighted average module manufacturing costs from 1992 to 1996. During this same period, U.S. module manufacturing capacity has increased by more than a factor of 6. Finally, the analysis indicates that both the public and the manufacturers will recapture the funds expended in R&D manufacturing improvements well before the year 2000.
Date: May 1996
Creator: Mitchell, Richard L.; Witt, C. Edwin; Thomas, Holly P.; Herwig, Lloyd O.; Ruby, Douglas S. & Aldrich, Clay C.
Partner: UNT Libraries Government Documents Department

Defining Requirements for Improved Photovoltaic System Reliability

Description: Reliable systems are an essential ingredient of any technology progressing toward commercial maturity and large-scale deployment. This paper defines reliability as meeting system fictional requirements, and then develops a framework to understand and quantify photovoltaic system reliability based on initial and ongoing costs and system value. The core elements necessary to achieve reliable PV systems are reviewed. These include appropriate system design, satisfactory component reliability, and proper installation and servicing. Reliability status, key issues, and present needs in system reliability are summarized for four application sectors.
Date: December 21, 1998
Creator: Maish, A.B.
Partner: UNT Libraries Government Documents Department

Photovoltaic module performance and durability following long-term field exposure

Description: Our investigations of both new and field-aged photovoltaic modules have indicated that, in general, today's commercially available modules area highly reliable product. However, by using new test procedures, subtle failure mechanisms have also been identified that must be addressed in order to achieve 30-year module lifetimes. This paper summarizes diagnostic test procedures, results, and implications of in-depth investigations of the performance and durability characteristics of commercial modules after long-term field exposure. A collaborative effort with U.S. module manufacturers aimed at achieving 30-year module lifetimes is also described.
Date: September 8, 1998
Creator: Ellibee, D.E.; Hansen, B.R.; King, D.L.; Kratochvil, J.A. & Quintana, M.A.
Partner: UNT Libraries Government Documents Department

Tracking the Sun: The Installed Cost of Photovoltaics in the U.S. from 1998-2007

Description: As installations of grid-connected solar photovoltaic (PV) systems have grown, so too has the desire to track the installed cost of these systems over time, by system characteristics, by system location, and by component. This report helps to fill this need by summarizing trends in the installed cost of grid-connected PV systems in the United States from 1998 through 2007. The report is based on an analysis of installed cost data from nearly 37,000 residential and non-residential PV systems, totaling 363 MW of capacity, and representing 76percent of all grid-connected PV capacity installed in the U.S. through 2007.
Date: February 11, 2009
Creator: Wiser, Ryan; Barbose, Galen & Peterman, Carla
Partner: UNT Libraries Government Documents Department

Photovoltaic performance and reliability workshop

Description: 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 activities 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.
Date: October 1, 1996
Creator: Kroposki, B.
Partner: UNT Libraries Government Documents Department

Design, fabrication, and certification of advanced modular PV power systems. Annual technical progress report, 8 September 1995--7 September 1996

Description: This report summarizes the activities performed during the first year of a nominal 2-year effort by Solar Electric Specialties Company (SES) under the Photovoltaic Manufacturing Technology (PVMaT) project of the National Photovoltaic Program. The goal of the SES contract is to reduce the installed system life-cycle costs by developing certified and standardized prototype products for two SES product lines--MAPPS{trademark} and Photogenset{trademark}. The MAPPS (modular autonomous PV power supply) systems are used for DC applications up to about a thousand watt-hours. The Photogensets are hybrid PV/generator systems for AC applications. SES expects these products to provide the basis for future commercial product lines of standardized certified, packaged systems.
Date: March 1, 1997
Creator: Lambarski, T. & Minyard, G.
Partner: UNT Libraries Government Documents Department

Photovoltaic energy program overview: Fiscal year 1994

Description: This is the 1994 overview for the Photovoltaic Energy Program. The topics of this overview include cooperative research projects to improve PV systems and develop pre-commercial prototypes of new PV products, expanding understanding of the fundamental mechanisms governing the formation and performance of PV materials, and helping US industry enhance its leadership position in the PV market.
Date: March 1, 1995
Partner: UNT Libraries Government Documents Department

Analysis of the Mount Laguna Photovoltaic Cell Failure

Description: From summary: The purpose of this analysis is to provide photovoltaic (P/V) system design and field engineers with an understanding of the primary factors which can cause individual P/V cells in a module or an array to be forced into reverse bias and eventual failure and to provide guidelines for the adequate protection of the cells.
Date: January 1981
Creator: Anderson, E.
Partner: UNT Libraries Government Documents Department

Photovoltaic array performance model.

Description: This document summarizes the equations and applications associated with the photovoltaic array performance model developed at Sandia National Laboratories over the last twelve years. Electrical, thermal, and optical characteristics for photovoltaic modules are included in the model, and the model is designed to use hourly solar resource and meteorological data. The versatility and accuracy of the model has been validated for flat-plate modules (all technologies) and for concentrator modules, as well as for large arrays of modules. Applications include system design and sizing, 'translation' of field performance measurements to standard reporting conditions, system performance optimization, and real-time comparison of measured versus expected system performance.
Date: August 1, 2004
Creator: Kratochvil, Jay A.; Boyson, William Earl & King, David L.
Partner: UNT Libraries Government Documents Department

Incorporation of NREL Solar Advisor Model Photovoltaic Capabilities with GridLAB-D

Description: This report provides a summary of the work updating the photovoltaic model inside GridLAB-D. The National Renewable Energy Laboratory Solar Advisor Model (SAM) was utilized as a basis for algorithms and validation of the new implementation. Subsequent testing revealed that the two implementations are nearly identical in both solar impacts and power output levels. This synergized model aides the system-level impact studies of GridLAB-D, but also allows more specific details of a particular site to be explored via the SAM software.
Date: October 19, 2012
Creator: Tuffner, Francis K.; Hammerstrom, Janelle L. & Singh, Ruchi
Partner: UNT Libraries Government Documents Department

Procedures for Determining the Performance of Stand-Alone Photovoltaic Systems

Description: This document provides the procedures for determining the performance of stand-alone PV systems. The procedures in this document provide a common approach for evaluating whether a given PV system is suitable to perform the function for which it was designed and manufactured to accomplish, and whether it will provide adequate power to run the load. These procedures cover small stand-alone PV systems. They cover complete outdoor system testing. Test results are valid only for the system that is tested.
Date: September 21, 1999
Creator: McNutt, P.; Kroposki, B.; Hansen, R.; DeBlasio, R. (National Renewable Energy Laboratory); Thomas, M. (Sandia National Laboratories); Durand, S. (Florida Solar Energy Center) et al.
Partner: UNT Libraries Government Documents Department

Soft Sun Cells

Description: Representing the Argonne-Northwestern Solar Energy Research (ANSER) Center, this document is one of the entries in the Ten Hundred and One Word Challenge. As part of the challenge, the 46 Energy Frontier Research Centers were invited to represent their science in images, cartoons, photos, words and original paintings, but any descriptions or words could only use the 1000 most commonly used words in the English language, with the addition of one word important to each of the EFRCs and the mission of DOE: energy. The mission of ANSER is to revolutionize our understanding of molecules, materials and methods necessary to create dramatically more efficient technologies for solar fuels and electricity production.
Date: July 18, 2013
Creator: Shastry, Tejas
Partner: UNT Libraries Government Documents Department

Analysis of Photovoltaic System Energy Performance Evaluation Method

Description: Documentation of the energy yield of a large photovoltaic (PV) system over a substantial period can be useful to measure a performance guarantee, as an assessment of the health of the system, for verification of a performance model to then be applied to a new system, or for a variety of other purposes. Although the measurement of this performance metric might appear to be straight forward, there are a number of subtleties associated with variations in weather and imperfect data collection that complicate the determination and data analysis. A performance assessment is most valuable when it is completed with a very low uncertainty and when the subtleties are systematically addressed, yet currently no standard exists to guide this process. This report summarizes a draft methodology for an Energy Performance Evaluation Method, the philosophy behind the draft method, and the lessons that were learned by implementing the method.
Date: November 1, 2013
Creator: Kurtz, S.; Newmiller, J.; Kimber, A.; Flottemesch, R.; Riley, E.; Dierauf, T. et al.
Partner: UNT Libraries Government Documents Department

High Efficiency Nanostructured III-V Photovoltaics for Solar Concentrator Application

Description: The High Efficiency Nanostructured III-V Photovoltaics for Solar Concentrators project seeks to provide new photovoltaic cells for Concentrator Photovoltaics (CPV) Systems with higher cell efficiency, more favorable temperature coefficients and less sensitivity to changes in spectral distribution. The main objective of this project is to provide high efficiency III-V solar cells that will reduce the overall cost per Watt for power generation using CPV systems.This work is focused both on a potential near term application, namely the use of indium arsenide (InAs) QDs to spectrally "tune" the middle (GaAs) cell of a SOA triple junction device to a more favorable effective bandgap, as well as the long term goal of demonstrating intermediate band solar cell effects. The QDs are confined within a high electric field i-region of a standard GaAs solar cell. The extended absorption spectrum (and thus enhanced short circuit current) of the QD solar cell results from the increase in the sub GaAs bandgap spectral response that is achievable as quantum dot layers are introduced into the i-region. We have grown InAs quantum dots by OMVPE technique and optimized the QD growth conditions. Arrays of up to 40 layers of strain balanced quantum dots have been experimentally demonstrated with good material quality, low residual stain and high PL intensity. Quantum dot enhanced solar cells were grown and tested under simulated one sun AM1.5 conditions. Concentrator solar cells have been grown and fabricated with 5-40 layers of QDs. Testing of these devices show the QD cells have improved efficiency compared to baseline devices without QDs. Device modeling and measurement of thermal properties were performed using Crosslight APSYS. Improvements in a triple junction solar cell with the insertion of QDs into the middle current limiting junction was shown to be as high as 29% under one sun illumination for a ...
Date: September 12, 2012
Creator: Hubbard, Seth
Partner: UNT Libraries Government Documents Department

NV Energy Large-Scale Photovoltaic Integration Study: Intra-Hour Dispatch and AGC Simulation

Description: The uncertainty and variability with photovoltaic (PV) generation make it very challenging to balance power system generation and load, especially under high penetration cases. Higher reserve requirements and more cycling of conventional generators are generally anticipated for large-scale PV integration. However, whether the existing generation fleet is flexible enough to handle the variations and how well the system can maintain its control performance are difficult to predict. The goal of this project is to develop a software program that can perform intra-hour dispatch and automatic generation control (AGC) simulation, by which the balancing operations of a system can be simulated to answer the questions posed above. The simulator, named Electric System Intra-Hour Operation Simulator (ESIOS), uses the NV Energy southern system as a study case, and models the system’s generator configurations, AGC functions, and operator actions to balance system generation and load. Actual dispatch of AGC generators and control performance under various PV penetration levels can be predicted by running ESIOS. With data about the load, generation, and generator characteristics, ESIOS can perform similar simulations and assess variable generation integration impacts for other systems as well. This report describes the design of the simulator and presents the study results showing the PV impacts on NV Energy real-time operations.
Date: January 2, 2013
Creator: Lu, Shuai; Etingov, Pavel V.; Meng, Da; Guo, Xinxin; Jin, Chunlian & Samaan, Nader A.
Partner: UNT Libraries Government Documents Department

Advanced Photovoltaic Inverter Functionality using 500 kW Power Hardware-in-Loop Complete System Laboratory Testing: Preprint

Description: With the increasing penetration of distribution connected photovoltaic (PV) systems, more and more PV developers and utilities are interested in easing future PV interconnection concerns by mitigating some of the impacts of PV integration using advanced PV inverter controls and functions. This paper describes the testing of a 500 kW PV inverter using Power Hardware-in-Loop (PHIL) testing techniques. The test setup is described and the results from testing the inverter in advanced functionality modes, not commonly used in currently interconnected PV systems, are presented. PV inverter operation under PHIL evaluation that emulated both the DC PV array connection and the AC distribution level grid connection are shown for constant power factor (PF) and constant reactive power (VAr) control modes. The evaluation of these modes was completed under varying degrees of modeled PV variability.
Date: January 1, 2013
Creator: Mather, B. A.; Kromer, M. A. & Casey, L.
Partner: UNT Libraries Government Documents Department

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

Description: Cost of installation and ownership of a 9.66-kilowatt (kW) residential photovoltaic system is described, and the performance of this system over the past 3 years is shown. The system is located in Colorado at 40 degrees latitude and consists of arrays on two structures. Two arrays are installed on a detached garage, and these are each composed of 18 Kyocera 130-W modules strung in series facing south at an angle of 40 degrees above horizontal. Each 18-panel array feeds into a Xantrex/Schneider Electric 2.8-kW inverter. The other two arrays are installed on the house and face south at an angle of 30 degrees. One of these arrays has twelve 205-W Kyocera panels in series, and the other is made up of twelve 210-Kyocera panels. Each of these arrays feeds into Xantrex/Schneider Electric 3.3-kW inverters. Although there are various shading issues from trees and utility poles and lines, the overall output resembles that which is expected from PVWatts, a solar estimate program. The array cost, which was offset by rebates from the utility company and federal tax credits, was $1.17 per watt. Considering measured system performance, the estimated payback time of the system is 9 years.
Date: June 1, 2012
Creator: Johnston, S.
Partner: UNT Libraries Government Documents Department