Energy-Exergy Analyzing of a Solar-Driven CCHP System Based on the First and Second Laws of Thermodynamics

In this study, a solar-driven combined cooling-heating and power system is proposed to achieve higher energy efficiency. Influences of compression ratio and direct normal irradiance are reported to evaluate the impact of design parameters. A compressed air energy system technology is utilized in the solar-driven Brayton cycle to run it in the peak consumption time, and a Rankine cycle is employed as an axillary cycle for more power generation. Results prove that the proposed system provides 11.75 MW pure power besides 3.2 MW heating and 6.8 MW cooling loads and it is able to run 5 hr in compressor deactivated mode passing peak consumption hours. Overall energy efficiency of the proposed system is estimated by more than 55% considering solar inlet beams energy, and 89% ignoring solar tower energy loss. The most exergy destructor component of the proposed system is solar heat absorber by 72% of general system destructed exergy.