- Title
- Performance evaluation of an off-grid building integrated photovoltaic system in Alice, Eastern Cape province, South Africa
- Creator
- Buma, Carine Lethem
- Subject
- Building-integrated photovoltaic systems Buildings -- Energy conservation Performance -- Evaluation
- Date Issued
- 2018
- Date
- 2018
- Type
- Thesis
- Type
- Masters
- Type
- MSc
- Identifier
- http://hdl.handle.net/10353/13227
- Identifier
- vital:39623
- Description
- The constant increase in the global demand for energy and the current crisis on global warming and climate change has prompted a dying quest for clean, sustainable and reliable sources of energy. Amongst numerous renewable energy technologies, harnessing energy from the sun is the most viable way of guaranteeing a clean and sustainable supply of energy. Also, photovoltaic energy is one of the ways of using energy from the sun, where sunlight is converted to electricity using photovoltaic panels. Furthermore, the integration of photovoltaic modules into buildings is one of the most elegant innovations of this technology, as it plays the dual role of supplying energy to the building as well as protecting the building from outdoor weather conditions. Moreover, operating off the grid offers the possibility of energy access to locations far off from the grid and individuals willing to gain some degree of energy independence. Evaluating the performance of existing off grid and/or building integrated photovoltaic systems is the key to guaranteeing sustainable development and advancement in the technology. Thus, the aim of this work was to evaluate the performance of an off-grid building integrated photovoltaic system that was installed at the Fort Hare Institute of Technology. This entailed performing an in-depth characterisation of the solar resource at this location, evaluating the performance of the modules under outdoor weather conditions and also evaluating the performance of the balance of system (BOS) components. The system was monitored for a period of nine months (between February and October 2017). A data acquisition system was designed for measuring and recording both electrical system parameters and meteorological parameters affecting the performance of the system. These meteorological parameters include; solar irradiance, ambient temperature, cell temperature, relative humidity, wind speed and direction. A detailed characterisation of the solar resource at this location was carried out. It was observed that the solar declination angle varied from -23.5o on the summer solstice to 23.5o on the winter solstice. Also, the solar altitude angle (at solar noon) which is a complementary angle to the zenith angle varied from 33.7o in June to 80.65o in December. During the summer months, longer day lengths were experienced because the sun traversed the sky over a longer time, rising south of east and setting south of west. Whereas, in the winter months, the path length of the sun was shorter, with the sun rising north of east and setting north of west, hence, shorter day lengths. The solar radiation incident on a 25o north facing solar collector was found to be in three components; beam, diffuse and reflected. The beam component was higher in summer whereas the diffuse component was higher in winter due to an increase in the air mass ratio. However, the total daily average radiation was highest in January (7.12 peak sun hours) and least in June (3.04 peak sun hours). Finally, a comparison between the calculated and measured values of solar radiation showed just a 1.1percent difference over the year with disparities being in the individual months.m The influence of outdoor weather conditions on the performance of the system was also evaluated. Operating temperatures were noticed to have a great impact on the output voltage and power of the PV array. Significant correlations existed between various meteorological parameters. Also, a multiple linear regression model was developed to ascertain the dependence of module temperature on solar irradiance, ambient temperature, relative humidity, wind speed and wind direction. The coefficient of determination for the model was 0.928, showing a strong relationship between cell temperature and the chosen predictors. Also, the six thermocouples installed at various locations of the PV array revealed variations in the operating temperatures of the modules. The modules on the east side of the array recorded relatively lower temperatures because of the ceiling that had been removed beneath one of the modules on this side of the array, which permitted the free flow of air. Furthermore, I-V measurements conducted on various strings of the array revealed so many steps (hotspots), indicative of module (or cell) mismatch on almost all the cell strings.
- Format
- 177 leaves
- Format
- Publisher
- University of Fort Hare
- Publisher
- Faculty of
- Language
- English
- Rights
- University of Fort Hare
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View Details Download | SOURCE1 | Combined Dissertation_27th September.pdf | 11 MB | Adobe Acrobat PDF | View Details Download |