Graduate Faculty of Environment, University of Tehran, Tehran, Iran
In this paper, detailed exergy and energy analysis of selected thermal power systems driven by parabolic trough solar collectors is presented. solar energy is used to feed a two stage steam Rankine cycle to supply domestic hot water. To determine the irreversibilities in each component and assess the system performance, a parametric study is performed to investigate the effects of varying design parameters and operating conditions such as the effects of the ambient temperature, solar radiation, and high pressure turbine pressure ratio and solar cycle mass flow rate, on the system energy and exergy efficiencies. An optimization with an evolutionary algorithm is applied to determine the best exergetic performance. This study reveals that the main source of exergy destruction is the solar collector where contributes more than 45% of total exergy destruction. In addition, heater, condenser and heat exchanger contribute to 16%, 15% and 14%, respectively. Finally, this study reveals that optimization using genetic algorithm improves the exergy efficiencies up to 58.03%.