Design and behaviour estimate of a novel concentrated solar-driven power and desalination system using S–CO2 Brayton cycle and MSF technology

Abstract

Solar-based power and desalination system using super-critical carbon dioxide (S–CO2) Brayton cycle can be considered as one of the most promising development directions of future energy. This study presents the design and behaviour estimate of a novel concentrated solar-driven power and desalination (CSPD) system using S–CO2 Brayton cycle and multi-stage flash (MSF) desalination technology. Operation simulations and exergic analysis of the CSPD system are conducted by utilizing the Ebsilon software. Operation behaviour estimate results of the CSPD system show that the efficiency of S–CO2 Brayton cycle is 36.6%. The electric power and freshwater daily output of the CSPD system are 50.1 MW and 4050.8 t. The CSPD system can perform the solar-driven electricity production and solar-driven desalination simultaneously according to the pre-set operation strategy. The exergic analysis results indicate that the solar tower receiver and heat exchanger of desalination system have the two maximum energy destructions as well as the two lowest exergy efficiencies. The economic analysis results reveal that the CSPD system has an equivalent LCOE (levelized cost of electricity) of 0.059 $∙kWh−1 and an LCOW (levelized cost of water) of 1.15 $∙t−1, which means the CSPD system is economically feasible.