Energy, exergy, and economic analysis of an integrated solar combined cycle power plant

Abstract

Integrated Solar Combined Cycle (ISCC) power plants based on Parabolic Trough Concentrators (PTCs) are the most efficient way for solar into electrical energy conversion. However, due to operation in several climate conditions, they need more efforts in their adaptation. This paper presents a techno-economic assessment of an ISCC - PTC system operating at Hassi R'mel site (Algerian Sahara) for which a new thermal storage system is incorporated. The obtained results reveal noticeable enhancements in the solar energy conversion and the overall power plant performance, hence offering better stability to the grid. As shown, the net solar thermal energy conversion ratio may reach up to 14%. Energy and exergy efficiencies are respectively equal to 56.06% and 53.29%, and about 46% of exergy received by the system is destructed. Moreover, the obtained Levelized Cost of Energy (LCOE) is around 9.75 ¢/kWh which is very promising, but still higher compared with a simple Combined Cycle (CC). At this geographical site, the modified ISCC - PTC power plant will allow saving about 30 million $ in natural gas consumption and 13 million $ in emission taxes.