Design and comparative analysis of photovoltaic and parabolic trough based CSP plants

Abstract

Solar energy can be exploited by two main methods to produce electrical energy, by means of photovoltaic (PV) panels to directly convert the sunlight into electrical energy and by using thermodynamic cycle with the help of concentrated solar power (CSP) approach to convert the heat of the sun into electricity. The objective of this research is to design and evaluate the performance of these two main methods of electrical energy generation at three different sites in Saudi Arabia. The parabolic trough CSP plant uses synthetic oil as heat transfer fluid and molten salt for the thermal energy storage system. Both CSP and PV plants have been designed for the same nameplate capacity of 100 MW. The technical comparison is performed based on solar to electrical efficiency, electrical output, capacity utilization factor, and land use factor while economic comparison includes net present value (NPV), net capital cost (NCC), levelized cost of energy (LCOE), and payback period. CSP plants have better electrical output and capacity utilization factor compared to PV plants while PV plants exhibit far better economic performance. Tabuk site is proven to be the best location for both CSP and PV plants. The best case CSP plant has 33.3% more electrical energy generation compared to the best-case PV plant. The capacity utilization factor of the CSP plant is 45.4% vs. 30.2% for PV plant. The CSP plant has 4.5 times higher NCC compared to PV plant. The LCOE of CSP plant is 2.73 times higher than that of PV plant. Overall CSP technology has better technical performance while PV technology is economically more feasible than the CSP technology at the proposed locations. This comparison between the two technologies could provide very useful guidelines for policy maker to choose the appropriate technology for a project.