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Polymers with pendant transition metal complexes for photovoltaic applications and nanofabricationsCheng, Kai-wing., 鄭啟穎. January 2008 (has links)
published_or_final_version / abstract / Chemistry / Doctoral / Doctor of Philosophy
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A case analysis of energy savings performance contract projects and photovoltaic energy at Fort Bliss, El Paso, TexasBarich, William J., Dessing, Brent L., Harley, Antonio B. 06 1900 (has links)
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.
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Workplace Electric Vehicle Solar Smart Charging based on Solar Irradiance ForecastingAlmquist, Isabelle, Lindblom, Ellen, Birging, Alfred January 2017 (has links)
The purpose of this bachelor thesis is to investigate different outcomes of the usage of photovoltaic (PV) power for electric vehicle (EV) charging adjacent to workplaces. In the investigated case, EV charging stations are assumed to be connected to photovoltaic systems as well as the electricity grid. The model used to simulate different scenarios is based on a goal of achieving constant power exchange with the grid by adjusting EV charging to a solar irradiance forecast. The model is implemented in MATLAB. This enables multiple simulations for varying input parameters. Data on solar irradiance are used to simulate the expected PV power generation. Data on driving distances are used to simulate hourly electricity demands of the EVs at the charging stations. A sensitivity analysis, based on PV irradiance that deviates from the forecast, is carried out. The results show what power the grid needs to have installed capacity for if no PV power system is installed. Furthermore, appropriate PV power installation sizes are suggested. The suggestions depend on whether the aim is to achieve 100 percent self-consumption of PV generated power or full PV power coverage of charging demands. For different scenarios, PV power installations appropriate for reducing peak powers on the grid are suggested. The sensitivity analysis highlights deviations caused by interference in solar irradiance.
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Sol-gel processed zinc oxide for third generation photovoltaicsZou, Elva Xin January 2012 (has links)
This thesis presents an experimental study of the incorporation and optimization of sol-gel processed aluminum doped zinc oxide (AZO) thin films in solar cell devices. I first optimized the optoelectronic properties of AZO thin films by manipulating the dopant incorporation, choice of precursor chemicals and post deposition anneal treatments. Results showed that improved performance could be attributed to several factors, including improved charge carrier concentration, mobility and conductivity. AZO thin films with transmittance of over 90% and resistivity values of the order of 10-2 Ω•cm have been achieved. I also demonstrated the successful application of these AZO thin films in organic photovoltaics (OPV), to serve as an alternative to ITO electrodes. I demonstrated greater than 2-fold improvement in device efficiency through the modification of the front contact/polymer interface using zinc oxide buffer layers. This improved the charge selectivity of the electrodes and energy level alignment at the interface while reducing the recombination of separated charges and the device's series resistance. Finally, I showed that the efficiency of inverted ZnO/PbS quantum dots solar cells can be enhanced by optimizing the p-type PbS thickness, UV treating the n-type ZnO layer and exposing the devices in the dark to nitrogen. Both ZnO and AZO systems were studied, and efficiency enhancement were demonstrated for a range of Al content from 0 to O.4at.%.
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Optimising the output power available from a photovoltaic panel through empirical testingOsamede, Asowata 09 1900 (has links)
M. Tech. (Department of Electronic Engineering, Faculty of Engineering and Technology) -- Vaal University of Technology / Einstein said, ‘‘the release of energy has not created a new problem, but has
made more urgent the necessity of solving an existing one’’. This dissertation
presents a method of optimising the available output power from a photovoltaic (PV)
panel through empirical testing as this will enable a higher yield of solar energy
thereby reducing dependence on traditional energy sources such as fossil fuels. The
proposed study intends using existing equations of latitude, mathematical models and
simulation packages in combination with the experimental data to analyse the
optimum tilt and orientation angles for PV panels. This will assist in identifying
ways to improve the installation of PV panels for optimum output power in the Vaal
Triangle.
Photovoltaic panels are semiconductor devices that convert incident direct beam
radiation to electrical energy and the panel is composed of several unitary cells
connected in series and/or in parallel. The optimisation process involves the
empirical testing of the entire system with the use of existing equations of latitude as
suggested by literature for PV installation in the southern hemisphere, power
conditioning devices (such as an DC-DC converter, solar charger with MPPT) in
order to validate results as well as the correlation of empirical results with a
simulation package.
The first objective was to have an overview of the types of PV panels that exist; this
was done in order to be able to make a right choice of PV panel to be used in this
research. A concise literature review was carried to enable this research to have a
background of existing information in the areas of optimisation of power from PV
panels. The next objective was to carry out a pilot study, this was done to form the
foundation for the main study. A data-logging interface circuit (DLIC) was
incorporated in the system for some reasons presented in subsequent chapters of this
dissertation. At the end of this study data were taken over a two year period, the data
were analysed and conclusions were drawn and some recommendation in optimising
available output power from a PV panel are suggested. / Vaal University of Technology, Telkom South Africa Ltd, TFMC Pty LTD, M-TEC and THRIP
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Projekt výstavby fotovoltaickej elektrárne / Project of the construction photovoltaic power plantMačugová, Radana January 2010 (has links)
The objective of this thesis is to analyze and evaluate the profitability of photovoltaic power plant construction project. The introductory part deals with general characteristics of solar energy and its utilization, with the Slovakian and the European legislation in connection with use of renewable energy resources. The practical part deals with solar energy from the perspective of private firm. One particular company is considering about the implementation of photovoltaic power plant. This section begins with the presentation of the private company and evaluation of its preconditions for this planned construction. The thesis also describes planned implementation of the project, namely its preparation, possibilities of obtaining funds, necessary communication with the public agencies, selection of technology and the construction itself. At the end is project evaluated from the point of profitability by selected indicators.
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Investigating the feasibility & impact of a solar array for Wits West Campus by using historical solar and power dataSingh, Ajeshni January 2016 (has links)
Master of Science in Engineering (Electrical)
University of the Witwatersrand
July, 2016 / This dissertation uses historical electrical consumption/load and actual solar radiation data to design a
solar array for the University of the Witwatersrand’s West Campus. The array must meet the campus’s
minimum demand as selling excess generated power back to the utility is not possible at this stage. The
financial and spatial impact of adjusting the size of the array, design losses and cloud cover are also
investigated. In addition to this, the influence on the payback period of financial variables such as taxes,
electricity and start-up costs are also explored.
The solar array system design process starts by determining the amount of power that the array must
produce or supplement. Thereafter, load estimates and electrical consumption figures that are provided
by utility bills or measured with load monitoring equipment are analysed. Furthermore, system losses
are factored in which ultimately increases the size of the array. Once all the input variables are analysed,
the amount of available solar radiation in the area where the array will be installed is required to
determine the amount of energy that the array can produce. Several free databases with this information
are available but it is found that this data over predicts the availability of solar radiation.
The University has been monitoring the electrical consumption of West Campus since 2012 and solar
radiation data is also available for this site. Comparing the satellite derived and measured datasets found
that the ground monitored data is 25 % more accurate and therefore better suited for designing a solar
array. Individually adjusting the design and financial variables changes the payback period between 3
– 17 %. Combining all the variables can reduce the payback of option 1 from 9.6 years to 6.1 years.
Clear legislation needs to be developed for the uptake of renewable energy resources and supported by
better rebates for renewable users and harsher taxes for non-renewable users. Should legislation change
and if additional capital is available, a larger array will benefit the University more and should be
installed as the difference between payback periods is not significant. This is mainly due to decreased
costs associated with a higher yield. The financial benefits of a larger array will also be more lucrative
if better rebates are enforced. / MT2017
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Analysis of the dynamic power requirements for controllable energy storage on photovoltaic microgridHoronga, Nyasha January 2016 (has links)
A dissertation submitted to the Facaulty of Engineering and the Built Environment,
University of the Witwatersrand in ful lment of the requirements of the degree of
Master of science in Engineering
September 2016 / Standalone microgrid studies are being done because an expansion of the existing
utility grids to supply power to remote communities is not feasible. Standalone
microgrids can be considered as one of the solutions for remote communities because
power can be generated close to these communities and it minimizes cost related to
power transmission. Renewable energy sources with large
uctuations are frequently
the source of power for these standalone microgrids. The
uctuating nature of these
renewable sources can often lead to frequent blackouts. This research is aimed at
minimizing power
uctuations using controllable energy storage systems. This MSc
focuses on the analysis of the ramp rate and delay time requirements for controllable
energy storage system used in standalone PV microgrids. Measured insolation data
and recorded load demand data for typical domestic appliances are used in this
study to analyze ramp rates present. The ramp rates are then used to determine
the range of energy storage ramp rate and delay time required to maintain the
microgrid voltage within the standardized range of 1pu 5%. From the recorded data
it has been observed that PV power can be sampled from at least 1-second intervals
without losing important information. The 1 second averaged ramp rates obtained
from the insolation data measurements have been found to have the highest value
of 0.12pu/sec. However, this ramp rate increases to 0.3pu/sec when the allowable
microgrid voltage band is narrow (1pu 5%). These insolation ramp rates are very
low compared to the ramp rates of typical loads that can be connected to a microgrid.
This means that, if the energy storage system is speci ed to meet the load ramp rate
requirements, it will be able to respond to the
uctuating PV power. The results
obtained from the simulations con rm that energy storage system ramp rate plays an
important role in the stability of a standalone microgrid. The minimum allowable
energy storage ramp rate was found to be 8.15pu/sec for load transients with a
ramp time of 20ms. This value is 28 times the energy storage ramp rate required to
cancel out insolation
uctuations. This further con rms that energy storage system
ramp rates must be speci ed using the load demand data. The maximum allowable
delay time was also found to be 0.53s to maintain the microgrid voltage within the
standardized range of 1pu 5%. This delay time is applicable when canceling out
only the insolation
uctuations. To cancel out load transient power
uctuations,
there should be no delay time. / MT2017
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Developing a photovoltaic MPPT systemUnknown Date (has links)
Many issues related to the design and implementation of a maximum power point tracking (MPPT) converter as part of a photovoltaic (PV) system are addressed. To begin with, variations of the single diode model for a PV module are compared, to determine whether the simplest variation may be used for MPPT PV system modeling and analysis purposes. As part ot this determination, four different DC/DC converters are used in conjunction with these different PV models. This is to verify consistent behavior across the different PV models, as well as across the different converter topologies. Consistent results across the different PV models, will allow a simpler model to be used for simulation ana analysis. Consistent results with the different converters will verify that MPPT algorithms are converter independent. Next, MPPT algorithms are discussed. In particular,the differences between the perturb and observe, and the incremental conductance algorithms are explained and illustrated. A new MPPT algorithm is then proposed based on the deficiencies of the other algorithms. The proposed algorithm's parameters are optimized, and the results for different PV modules obtained. Realistic system losses are then considered, and their effect on the PV system is analyzed ; especially in regards to the MPPT algorithm. Finally, a PV system is implemented and the theoretical results, as well as the behavior of the newly proposed MPPT algorithm, are verified. / by Thomas Bennett. / Thesis (Ph.D.)--Florida Atlantic University, 2012. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
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Método de caracterização da irradiação para geração fotovoltaica: uma análise sistêmica da modelagem da energia primária. / Irradiation characterization method for photovoltaic power generation: a systemic analysis of the modeling of primary energy.Relva, Stefania Gomes 16 December 2016 (has links)
O objetivo desse estudo é analisar e sistematizar os elementos necessários à modelagem da energia primária solar para geração fotovoltaica em escala. Metodologicamente, investigam-se os assuntos inerentes à solarimetria e a caracterização da radiação solar, desde a formação das equações que definem a incidência da radiação no topo da atmosfera, o desenvolvimento tecnológico de radiômetros, até as normas e critérios de classificação desses equipamentos. Também são elementos metodológicos a caracterização do irradiância solar, incluindo algoritmos de tratamento de dados de irradiância, os processos de estimativa de irradiação para a agricultura e análises probabilísticas de índices de transmitância atmosférica. Busca-se a aplicação das etapas de caracterização e a análise do recurso, definidas neste estudo, por meio da utilização dos dados fornecidos por duas estações solarimétricas: ESUPP e ESPEL. Como resultados são definidos a média diária parcial anual de disponibilidade do recurso para uma região no interior do estado de São Paulo (localização da ESUPP) em 5,29 kWh/m² e a média diária anual de disponibilidade do recurso para a região metropolitana da cidade de São Paulo (localização da ESPEL) em 4,41 kWh/m², além disso verifica-se que a relação entre as componentes global horizontal, difusa horizontal e direta vertical varia para os dados das duas estações solarimétricas, de modo que, parte significativa dos dados da ESPEL apresenta medições de irradiância global horizontal (IGH) entre 12% e 13% superiores à respectiva componente difusa horizontal (IDH) somada a parcela vertical da respectiva componente direta normal (IDNcos?z), enquanto que, essa mesma relação para os dados da ESUPP atendem à relação IGH=IDH+IDNcos?z dentro do intervalo aceitável de mais ou menos 10%. Verifica-se também caráter trimodal das curvas de densidade de probabilidade do índice de transmitância da irradiância global para os dados da ESPEL, enquanto os dados da ESUPP refletem em curva de caráter bimodal. Assim é possível constatar a necessidade de definição de um modelo universal de previsibilidade do recurso e verifica-se que os insumos mais relevantes para o modelo podem variar de região para região dada a caracterização geográfica e de microclima. Conclui-se, portanto, a indiscutível necessidade de dados radiométricos confiáveis medidos em solo para avanços científicos, tecnológicos e comerciais do aproveitamento do recurso solar como fonte energética diante do atual contexto da busca por fontes alternativas de energia limpa e evidencia-se o grande caminho a ser percorrido para a consolidação de uma rede confiável, monitorada e amplificada de medições solarimétricas no Brasil e no mundo. / The purpose of this study is to analyze and to systematize the elements required for modeling primary solar energy for photovoltaic generation in large scale. Solarimetric subjects and subjects related to solar irradiance flux characterization, from the formation of the equations that define the incidence of radiation at the top of the atmosphere, the technologic development of radiometers and the rules and criteria for the classification of these measurement instruments, are methodologically investigated. The characterization of the irradiance flux, including irradiance data treatment algorithms, the irradiance estimate processes for agriculture, and the probability analyses of atmosphere transmittance indexes are also methodological elements. The steps of characterization and resource analysis defined in this study are applied, using data provided for two solarimetric stations: ESUPP and ESPEL. Results showed that the partial annual daily average for resource availability in the countryside of São Paulo State (ESUPP location), is 5.9 kWh/m², and the annual daily average for resource availability in the metropolitan area of São Paulo City (ESPEL location) is 4.41 kWh/m². Moreover, it was observed that the relation between the global horizontal, diffuse horizontal and direct vertical components varies between both solarimetric stations, such that a significant part of the ESPEL data shows global horizontal irradiance (GHI) between 12% and 13% above the respective diffuse horizontal irradiance (DHI) plus the vertical portion of the respective direct normal component (DNIcos?z), while the same relation for the ESUPP data attend the GHI=DHI+DNIcos?z relation within the acceptable range of 10%, give or take. ESPEL data presented trimodal characteristics for the probability density curves of the transmittance index for global irradiation, while ESUPP data reflect on the same curve, with bimodal characteristics. Therefore, it is possible to verify the need of the determination of a universal predictability model of the resource and it is possible to affirm that the more relevant inputs to the model can vary from region to region, depending on the geographic character and microclimate. In conclusion, there is an unquestionable need for reliable radiometric data, measured in ground, for scientific, technologic and commercial advances to improve the use of solar resource as energy source, considering the current scenario, which demands alternative sources for clean energy. It is also evident that there is still a long path to be tracked in order to consolidate a reliable, monitored and amplified network for solarimetric measurements in Brazil and in the world.
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