Design and Performance Analysis of a Tower Solar Energy S-CO2 Brayton Cycle Tri-Generation System

Against the backdrop of global energy transition and increasingly severe environmental conditions, developing clean and efficient energy systems has become crucial. This study aims to investigate a solar tower receiver tri-generation (STRT) system combining supercritical CO2 (S-CO2) Brayton cycle and organic Rankine cycle (ORC), with the objective of achieving the production of electricity, hydrogen, and oxygen. The modeling of the STRT system is completed by using Ebsilon, and the performance of the STRT system is analyzed. The results show that the output power and efficiency of the S-CO2 Brayton cycle are 62.29 MW and 48.3%, respectively. The net power and efficiency of ORC are 8.02 MW and 16.35%. The hydrogen and oxygen production rates of the STRT system are 183.8 kg·h−1 and 1470.4 kg·h−1, respectively. The STRT system shows stable and effective operation performance throughout the year. Through the exergy analysis, the exergy losses and exergy efficiencies of different components of the STRT system are obtained. The solar tower has the largest exergy loss (218.85 MW) and the lowest exergy efficiency (63%). The levelized electricity cost and the levelized hydrogen cost of the STRT system are 0.0788 USD·kWh−1 and 2.97 USD·kg−1 with a recovery period of 8.05 years, which reveal the economic competitiveness of the STRT system.