Thermodynamic and economic analysis of solar-assisted chemical looping electricity storage system

Abstract

Three types of oxygen carriers (Mn-based, Co-based, and Cu-based) are employed in solar-assisted chemical looping electricity storage (SCLES) systems with two different regenerator layouts (Scheme I and Scheme II). Scheme I and Scheme II feature increasing the inlet stream temperature and the outlet stream temperature of the charging compressor, respectively. If system efficiency is treated as the evaluation criterion, Scheme II shows promising thermodynamic potential. By comparing the thermodynamic performances of the three types of oxygen carriers, the SCLES system using the Mn-based oxygen carrier has the highest system efficiency, reaching 50.32 %. It is at least 4.64 % and 15.31 % higher than that of the Co-based oxygen carrier and Cu-based oxygen carrier, respectively. Through economic assessment, the levelized cost of electricity storage (LCOES) of the SCLES using Mn-based oxygen carrier is at least 2.04 % and 24.4 % lower than that of the Co-based oxygen carrier (LCOES = 0.098 $/kWh) and the Cu-based oxygen carrier (LCOES = 0.127 $/kWh), respectively. The operation parameters are as follows: the heating temperature of solar is 1200 °C, the charging temperature is 960 °C, the temperature difference between charge and discharge is 10 °C, and the reaction pressure is 2 bar. It is successfully verified that the Scheme II using the Mn-based oxygen carrier is superior to other designs in terms of economic and thermodynamic performance.