An organic Rankine cycle system for solar thermal power applications

This paper presents an organic Rankine cycle (ORC) system for combined heat and power utilizing solar thermal energy and natural gas as well. The ORC investigated in this work consists of a heat source, an evaporator, a scroll expander, a condenser, a fluid pump, a recuperator and a control unit. The ORC produces shaft power that runs a generator. The experimental ORC unit has an electric power capacity of 1000 We. Its advantages include short start-up time, clean and automatic operation, low maintenance and very low noise level. It is well suited for small-scale solar thermal power applications or hybrid solar and natural gas energy systems. A mathematical model was established to assess the thermodynamic performance of the ORC system under various conditions. Power output and thermal efficiency were calculated using the established model.