No description available.

MBA Professional Report / The purpose of this MBA Project is to review existing policy of the Federal Energy Management Program under the purview of National Renewal Energy Laboratory (NREL) for Energy Savings Performance Contracts (ESPCs). This project will assess the ability for the Department of Defense to incorporate emerging technologies in alternative energy to supplement or replace existing power sources for DoD installations within the current Energy Savings Performance Contract policy. To do this the project will review previous and existing Energy Savings Performance Contracts. Further, this project will conduct a cost-benefit analysis of conventional power versus emerging photovoltaic energy for the Army’s Fort Bliss in El Paso, TX. The project will also analyze energy demands based on a new force alignment at Fort Bliss in accordance with the recent Base Realignment and Closure (BRAC) findings. The project will review current Energy Performance Contract Policy and recommend changes to allow for the use of emerging alternative energy technologies.

Thesis Submitted in Partial Fulfilment of the Requirements for the Degree of Master of Technology: Electrical Engineering (Energy) in the Department of Electrical, Electronic and Computer Engineering at the Cape Peninsula University of Technology, South Africa. / In photovoltaic power systems, the DC/AC conversion efficiency depends on weather conditions causing PV inverters to operate under fluctuating input power from PV modules. The peak efficiency stated by the inverter manufacturers are often used by project designers to estimate how much power PV plants can produce. However, the varying nature of the DC input power to the inverters, occasioned by varying irradiation and temperature, leads to deviations of the actual efficiency from the peak efficiency. Literature surveys prove that inverter efficiencies must be evaluated against local irradiation profiles to get more precise annual energy yield estimations, since meteorological conditions and solar irradiation profiles vary from one site to another around the planet.

This thesis analyzes the general performance and design requirements of photovoltaic(PV) systems, and specifically how they relate to the design of a system intended to supply power to a rotating satellite. The PV array geometry was discussed, different DC-DC converter topologies were analyzed, and optimum array geometry and converter topologies were determined. The potential reference quantities for use in control of the system are examined. Due to its comparably greater linearity with respect to changes in apparent load and its relative insensitivity to insolation changes, voltage was determined to be the best reference quantity for use in stable tracking of the maximum power operating point of photovoltaic modules. The preceding work is used to design and model a photovoltaic system for a rotating satellite ensuring the supply of the maximum available power as well as stable operation. Simulations of the system are performed at rotational velocities up to 300 rev/min and its behavior is analyzed to demonstrate the validity of the preceding work. It was concluded that: ● parallel connected photovoltaic panels provide greater efficiency than series connected panels. ● Buck, Boost, and Cuk Converter architectures are best suited to PV applications ● PV Voltage is the best reference quantity for use in stable control of PV systems.

No description available.

Orientador: Luís Carlos Origa de Oliveira / Resumo: Na busca de soluções inovadoras para atender o aumento da demanda de consumo de energia elétrica, as fontes de energia de natureza fotovoltaica tem sido um dos principais pilares deste seguimento. São fontes intrinsicamente renováveis e o impacto sobre o meio ambiente resultante dos processos de produção de energia elétrica é praticamente desprezível, contribuindo de forma inequívoca para a sustentabilidade do planeta. Neste cenário, a expansão das aplicações de geradores fotovoltaicos é notável em praticamente todas as regiões industrializadas no mundo e, em alguns casos, já representa uma parcela significativa dos insumos energéticos de países desenvolvidos e em desenvolvimento. Apesar dos benefícios proporcionados pelo crescente uso desta tecnologia, em geral, as redes elétricas de distribuição de energia em operação, não foram planejadas para incorporar esta geração distribuída, em larga escala. Estudos recentes revelam que 10% de penetração de sistemas fotovoltaicos em relação a demanda da rede já pode causar impactos relevantes sobre o comportamento do sistema elétrico, sobretudo no tocante à regulação de tensão. Neste contexto, este trabalho tem por meta investigar as condições operacionais de redes de distribuição de energia, sob a influência de sistema fotovoltaico com relação aos impactos produzidos no perfil de tensão dos alimentadores. Assim, na perspectiva dos diferentes procedimentos convencionais utilizados para adequação dos níveis de tensão, discute-se a apli... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In the search for innovative solutions to meet the increasing demand for electricity consumption, photovoltaic energy sources have been one of the main pillars of this follow-up. They are intrinsically renewable sources and the impact on the environment resulting from the processes of electric power production is practically negligible, contributing unequivocally to the sustainability of the planet. In this scenario, the expansion of photovoltaic applications is notable in practically every industrialized region in the world, and in some cases already represents a significant share of the energy inputs of developed and developing countries. Despite the benefits provided by the growing use of this technology, in general, power distribution networks in operation were not planned to incorporate this distributed generation on a large scale. Recent studies show that 10% penetration of photovoltaic systems in relation to the demand of the grid can already have a significant impact on the behavior of the electrical system, especially in relation to voltage regulation. In this context, this work aims to investigate the operational conditions of power distribution networks under the influence of photovoltaic system in relation to the impacts produced on the voltage profile of the feeders. Thus, in the perspective of the different conventional procedures used to adjust the voltage levels, the applicability of some possible solutions is discussed, based on the R / X ratio behavior in th... (Complete abstract click electronic access below) / Mestre

The development of organic photovoltaics (OPVs) has attracted a lot of attention due to their potential to create a low cost flexible solar cell platform. In general, an OPV is comprised of a number of layers of thin films that include the electrodes, active layers and barrier films. Thus, with all of the interfaces within OPV devices, the potential for failure exists in numerous locations if adhesion at the interface between layers is inherently low or if a loss of adhesion due to device aging is encountered. To date, few studies have focused on the basic properties of adhesion in organic photovoltaics and its implications on device reliability. In this dissertation, we investigated the adhesion between interfaces for a model multilayer barrier film (SiNx/PMMA) used to encapsulate OPVs. The barrier films were manufactured using plasma enhanced chemical vapor deposition (PECVD) and the interfacial fracture toughness (Gc, J/m2) between the SiNx and PMMA were quantified. The fundamentals of the adhesion at these interfaces and methods to increase the adhesion were investigated. In addition, we investigated the adhesive/cohesive behavior of inverted OPVs with different electrode materials and interface treatments. Inverted OPVs were fabricated incorporating different interface modification techniques to understand their impact on adhesion determined through the interfacial fracture toughness (Gc, J/m2). Overall, the goal of this study is to quantify the adhesion at typical interfaces used in inverted OPVs and barrier films, to understand methods that influence the adhesion, and to determine methods to improve the adhesion for the long term mechanical reliability of OPV devices.

Tools and algorithms are proposed that are useful for planning, designing, and operating a distribution network with a significant penetration of distributed generation (DG). In Task 1, a PV system simulation program is developed, which incorporates the most rigorous models for the calculation of insolation, module temperature, and DC and AC power output of a PV system. The effect of random inverter failures is incorporated in the model of a PV system, and a novel performance-derating coefficient is introduced. Furthermore, a novel inverter control algorithm is presented for systems with multiple inverters. The algorithm is designed to increase overall DC/AC conversion efficiency by selectively shutting down some of the inverters during periods of low insolation, thus forcing the remaining inverters to operate at higher efficiency. In Task 2, a procedure is developed to incorporate the uncertainties imposed by stochastic, renewable DG into the conventional tools for analysis of distribution systems. A clustering algorithm is proposed to reduce large input data sets that result from the interaction of stochastic processes that drive DG output with field measurements of feeder load profiles. In addition, a procedure is proposed to determine the boundary points of the original data set, which yield feeder extreme operating conditions. Finally, a Monte Carlo analysis using a reduced data set is presented, to determine the effects of deploying a large number of renewable DG systems on a distribution feeder. In Task 3, the reliability model of an asymmetric, three--phase, non-radial distribution feeder equipped with capacity-constrained DGs is developed and used to quantify the potential reliability improvements due to the intentional islanded operation of parts of the feeder. A procedure for finding optimal positions for DG and protection devices is presented using a custom-tailored adaptive genetic algorithm.

The thesis discusses the restrictions of photovoltaic industrial market and technical characteristics, and the reactions of Japanese government and photovoltaic industry. Furthermore, this thesis studies what are the Japanese government industrial policies and Japanese photovoltaic enterprises¡¦ global strategies for the correction of photovoltaic market failure status. First of all, the thesis discusses the limitations of photovoltaic industrial market and technical characteristics. After realizing the market and technical characteristics of photovoltaic industry, the dissertation discovers the corrections that Japanese government and Japanese enterprises made to response the market and technical characteristics of photovoltaic industry. To realize the corrections that Japanese government and Japanese enterprises made, the thesis discusses the Japanese government photovoltaic industrial policies from 1970s and the worldwide strategies of Japanese photovoltaic enterprises. Under the market failure status of photovoltaic industry, how do the policies of public sectors and the strategies of private sectors interact in addition.

Though relatively young, the field of organic electronics is a rapidly growing market and considerable research is being done in creating a whole range of devices from organic molecules from organic field effect transistors to LEDs to photovoltaic devices. The field of organic photovoltaic in particular has become important in recent years with the push for newer, renewable sources of energy to end the dependence on fossil fuels. While the efficiencies of organic photovoltaic devices continue to rise, one barrier to their commercial adoption has been the limited lifetimes of these devices. While certain degradation methods of organic photovoltaics, such as photo-oxidation, have been extensively studied and solutions to these problems, such as encapsulation, are being researched, certain other degradation mechanisms are less understood and studied. The focus of this thesis is on one such degradation mechanism, UV degradation, specific to the ITO-pentacene interface in pentacene/C60 organic photovoltaic devices. Attempts were made to increase the lifetime of the devices by using phosphonic acids or oxygen plasma to modify the surface of the ITO. While conducting these experiments, the lack of a system to test the lifetime of multiple devices for long periods of time became apparent. As such as system was a requirement for future research into the lifetimes of organic photovoltaic devices a system was designed and built. The system would operate the photovoltaic device in a way comparable to its end-use and would allow over 100 devices to be tested simultaneously for durations exceeding 10,000 hours if necessary. This system would allow for statistically significant lifetime testing to be carried out in the future.