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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Energy rating of photovoltaic modules

Anderson, David James January 2002 (has links)
No description available.
2

Performance measures for residential PV structural response to wind effects

Goodman, Joseph Neal 27 May 2016 (has links)
This thesis applies structural reliability measures for the performance based design of residential PV system structures. These measures are intended to support designers in delivering systems with quantified and consistent reliability. Existing codified practices prescribe global factors (allowable stress design) and partial factors (load and resistance factor design) intended to provide an acceptable level of reliability as defined by historical practice. When applied to residential PV systems this prescriptive approach has two flaws, (1) calibration efforts needed to ensure consistency across structural system types have not kept up with the commercially available system types and (2) the actual expected reliability is not quantified and available to support decisions. The proposed reliability measures include probability of failure conditioned to wind speed in a fragility curve and the reliability index β, both of which are commonly used in performance based design. The approach is demonstrated through the application of the reliability measures to code compliant designs. Diverse system types are utilized to demonstrate how the existing code prescribed approach may lead to non-uniform structural performance. For each of the system types on which the reliability measures are demonstrated, a code compliant design is developed for three roof slopes, wind tunnel testing is conducted to provide an experimental measure of wind pressure coefficients, system specific fragility curves are generated to quantify the probability of failure conditioned to a set of wind speeds, and then, a site specific wind model is applied to produce a probability of failure and reliability index β. Through the performance based approach proposed in this thesis, two key outputs show non-uniform and unanticipated structural performance of PV systems designed according to the prescriptive code method. The two key outputs which illustrate this finding are fragility curves which illustrate the probability of failure over a range of wind speeds and reliability index, β values which couple the structural and wind distributions for a single measure of reliability.
3

Module-level autonomous settingless protection and monitoring for standalone and grid-connected photovoltaic array systems using quadratic integration modeling

Umana, Aniemi 07 January 2016 (has links)
This research applies a recently developed dynamic state-estimation based protection scheme, the settingless protection, to the photovoltaic (PV) industry for the first time. At this time, the proposed protection algorithm has been implemented on traditional protection zones for individual power system devices, but this research extends this protection to a microgrid, specifically, a system of PV network composed of several PV modules. Several illustrative examples on various anomalies such as high impedance faults and shorted-out PV modules have been provided to demonstrate the effectiveness of this protection scheme. The detection of these anomalies has been demonstrated in the presence of changing atmospheric conditions, and with the operation of maximum power point tracking (MPPT) equipped dc-dc converters. This protection scheme requires an accurate model of the PV module, therefore, a two-diode PV model has been developed using quadratic integration modeling. In this PV model development, a scaling factor is applied to the Taylor series expansion of the exponential terms of the model of the PV module. Then the higher order terms of the Taylor series expansion are reduced to at most second order terms using the quadratization technique. Furthermore, a novel approach for extracting the PV parameters, namely, the ideality constants, leakage currents, PV module internal current, shunt and series resistances, has been presented. A comparison was performed between numerically generated data using the determined PV module parameters and data measurements from a physical PV module. It was shown that the maximum error from this comparison was below 0.12A, and less than 0.05A around the maximum power point region of the PV modules used for this research. The residual data from the PV array protection scheme has been used to develop a method for identifying the location of faulted PV modules. Also, condition-based monitoring of the PV array system has also been presented with examples. From the PV array system monitoring, the shading and underperformance of a PV module have been identified. From the contributions of this research, an accurate module of the PV array has been developed in a form that can be integrated with other power system devices. This accurate module can be used for state estimation of the PV array, load flow analysis, short circuit analysis, and other power system analytical studies. Also, by determining the location of the faulted PV module, the time to identify this faulted PV module in a large PV installation is drastically reduced. Lastly, by identifying shading conditions and underperforming PV modules, the PV system operator can quickly bring the underperforming module or modules to optimal performance, thereby, maximizing the power yield of the PV array, and maximizing the revenue of the PV system owner.
4

Vidareutveckling av PV/T-receiver för koncentrerat solljus

Fjällström, Viktor January 2010 (has links)
The rising demand for electricity and heat raises a big challange for the society and engineers. Many products have been introduced to the market to supply more energy to the energy systems. Absolicon AB is a Swedish company that develops and markets a combined heat and power generating product. The product, Absolicon X10, uses a parabolic trough to concentrate the radiation of the sun onto a receiver. The receiveris equipped with mono crystalline solar cells and is cooled by a circulating liquid media. The electricity is supplied to the local grid and the heat is supplied to a local heating system. In this master thesis, the author has developed a number of tests for the Absolicon X10 with the superior goal to enhance the quality and electrical performance. The main areas of interest were: The ribbon connecting the solar cells The correlation between indoor and outdoor performance How the position of the receiver in the trough affects the electrical output A test method for evaluation of ribbons was developed and was applied to a new type of ribbon. The method showed that this new type of ribbon was not good enough for implementation in the production chain. Two types of indoor testing methods were developed, with the aim of determine the electrical performance of receivers. Both methods were unable to do so, but one of them might be good enough with some improvements. A position of the receiver which gives higher electrical output and higher tolerance for the tilt angle of the through was found.
5

Using GIS and Remote Sensing Techniques for Solar Panel Installation Site Selection

Li, Dongrong 26 September 2013 (has links)
Solar energy replacing conventional non-renewable energy has been widely implemented around the world. Currently, one of the most challenging problems is how to improve the efficiency of producing solar energy. Before installing solar panels, assessing where solar panels should be placed can significantly benefit panel performance. This study aims to conduct a site selection analysis for solar panel installation using Geographical Information Systems (GIS). The University of Waterloo main campus and the City of Waterloo were selected as study areas for micro-scale and macro-scale, respectively. The focus of the micro-scale analysis is on building rooftop installations, while the macro-scale analysis considers ground-mounted installation at the city-level. Knowledge about solar gains incident on different land cover types (e.g., urban and farmland) is useful for assessing potential solar energy installation sites in a local area. In this study, Light Detection and Ranging (LIDAR) data were applied to automatically derive accumulated solar radiation energy under clear-sky and overcast conditions at the micro-scale level from which ideal sites for solar panel placement on building rooftops were determined. Macro-scale solar radiation maps were based on Digital Elevation Model (DEM) data using ArcGIS software. Optimal ground-mounted solar panel installation sites were determined using a multi-criteria analysis approach that considered various environmental and socioeconomic factors. A questionnaire survey was distributed to select solar power companies in Southern Ontario to assess current solar panel installation practices, which were then used to better inform and modify the GIS multi-criteria approach. Finally, a feasibility assessment was performed with ground truth information to verify selected sites.
6

Expansion Planning of Distribution Systems Considering Distributed Generation and Reliability Cost

Chiu, Shian-Chun 06 July 2009 (has links)
This thesis investigates the capacity expansion of distribution substation of each service area considering PV system penetration to achieve the cost effectiveness of substation investment to comply with the service reliability. With the land use planning of Kaohsiung City Government, the load density of each small area for the target year is derived according to the final floor area and development strength of the land base. The load forecasting of each small area is then solved by considering the load growth of each customer class and a Markov model is applied for the forecasting of solar energy, which is then included in the expansion planning of substations. The forecasting of annual peak loadings for each area over the future 20 years is performed by the time series method based on the historical load data and load type of customers served. The forced outage rate ¡]FOR¡^ of main transformers in the substations is used to solve the loss of load expectation¡]LOLE¡^ according to the peak loading of each service area. By this way, the capacity expansion planning of main transformers to meet the service reliability can therefore be derived. To further enhance the distribution system planning, the capacity transfer capability of main transformers and the tie line flow capacity between different areas are considered too. It is found that the expansion planning of main transformers by the proposed methodology can provide better cost effectiveness of transformer investment to satisfy the service reliability as well as the system peak loading.
7

Peer effects and ownership costs in the diffusion of residential solar photovoltaic in California

Hoontrakul, Pimjai 19 July 2012 (has links)
This research analyses the California Solar Initiative (CSI) Program data to identify and describe peer effects and price elasticity to adoption affecting the patterns of residential PV adoption. Descriptive statistics and adoption trends are analyzed to explore the impacts of peer effects and third-party owned system on the diffusion of residential solar PV in California. As the residential solar PV technology is still in an early stage of market formation, understanding the patterns of adoption in relatively more mature market can have broad implications for wider diffusion of the technology at the national level. In the first part of the thesis, I build an econometric model to estimate the influence of system cost and peer effects on the rate of diffusion at the zip code-level. The results reveal significant and positive installed base effects in the rate of future adoption. These results provide support to the hypothesis that peer effects help accelerate the adoption of new technologies. The cost-to-customer reduction is negative and significant at the state level. The impact of installed base in inducing new adoption is larger in zip codes with higher overall adoptions. The second part of the thesis presents trends in installation and choice of system capacity of major adoption clusters in California and analyzes the spread of third-party owned systems. Evidence from major adoption clusters in California has shown that growth in leasing adoption exhibits exponential characteristics while growth of customer owned system shows strongly linear feature. This suggests that third-party owned systems play a role in expanding the solar PV market to a significantly large population, especially given that this business would significantly reduces information cost associated with PV adoption. These results offer direct policy and marketing insights that would be useful in speeding up the diffusion of residential PV. / text
8

Using GIS and Remote Sensing Techniques for Solar Panel Installation Site Selection

Li, Dongrong 26 September 2013 (has links)
Solar energy replacing conventional non-renewable energy has been widely implemented around the world. Currently, one of the most challenging problems is how to improve the efficiency of producing solar energy. Before installing solar panels, assessing where solar panels should be placed can significantly benefit panel performance. This study aims to conduct a site selection analysis for solar panel installation using Geographical Information Systems (GIS). The University of Waterloo main campus and the City of Waterloo were selected as study areas for micro-scale and macro-scale, respectively. The focus of the micro-scale analysis is on building rooftop installations, while the macro-scale analysis considers ground-mounted installation at the city-level. Knowledge about solar gains incident on different land cover types (e.g., urban and farmland) is useful for assessing potential solar energy installation sites in a local area. In this study, Light Detection and Ranging (LIDAR) data were applied to automatically derive accumulated solar radiation energy under clear-sky and overcast conditions at the micro-scale level from which ideal sites for solar panel placement on building rooftops were determined. Macro-scale solar radiation maps were based on Digital Elevation Model (DEM) data using ArcGIS software. Optimal ground-mounted solar panel installation sites were determined using a multi-criteria analysis approach that considered various environmental and socioeconomic factors. A questionnaire survey was distributed to select solar power companies in Southern Ontario to assess current solar panel installation practices, which were then used to better inform and modify the GIS multi-criteria approach. Finally, a feasibility assessment was performed with ground truth information to verify selected sites.
9

Stand-alone hybrid energy systems

Sharma, Hiteshi 10 April 2018 (has links)
Portugal is highly dependent on imported fuels when it comes to the energy sector. The government continuously aims at creating a sustainable and competitive renewable energy system. The need for balancing the supply and load demand in the electrical sector is a priority. To promote economic development in Portugal, the government always intend to initiate new projects like the construction of the solar plant. The United Kingdom (UK) solar company WELink Energy will develop a 220MW solar plant in south Portugal and have signed an Engineering, Procurement and Construction (EPC) agreement with China Triumph International Engineering Cooperation (CTIEC). There are 4 ongoing solar projects in Algarve that will produce enough electricity to ful ll the load demand. The problem that the government is facing is the expansion of hybrid power system using other renewable resources in order to overcome climatic changes. In order to design a hybrid system, it is very important for the government to consider the minimum net present cost con guration for ful lling the load demand. The standalone hybrid system consists of a photovoltaic array (PV), a wind turbine (WT), a diesel generator (DG) and a battery. Di erent scenarios have been considered using HOMER software to obtain the lowest net present cost of the hybrid system. The results will establish the con guration to eradicate the problems the villagers are undergoing due to unavailability of electricity. This will lead to enhanced job opportunities and better living conditions in Algarve. / Graduate
10

Photovoltaics Systems Sizing

Taymur, Eyup January 2009 (has links)
No description available.

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