Multi-objective optimization and 4E analyses of the solar energy assisted direct-heated sCO2 power cycle for low-temperature applications

The aim of this study is to investigate the performance of the intercooling and reheating supercritical CO2 Brayton cycle (SCBC) for low-temperature solar applications. Thermodynamic, exergo-economic, and exergo-environmental analyses of SCBC are examined. Furthermore, parametric research is performed to assess the effects of operating parameters on plant performance. Finally, multi-objective optimization (MOO) of the solar energy-based integrated plant is conducted for optimum operating conditions, taking into account the main parameters affecting the system performance. Considering the analyses, the generated power is calculated as 0.380 kW, while the system's energetic and exergetic efficiencies are found as 3.91% and 4.20%, respectively. According to the exergo-economic analysis results, exergo-economic analysis, the total cycle's cost rate is 0.889 $/h, the total cost rate of exergy destruction is 0.274 $/h, the total exergo-economic factor value is 69.14%, and the total purchase cost of the plant is 31,422$. Moreover, the total collector number is 23, the compressor inlet pressure is 8067.57 kPa, and the system's entire purchase cost is 41,031 $, according to the MOO results. The exergy efficiency of the system improved by 20.53%, as an outcome of the optimization analysis.