Thermodynamic analysis of a combined cooling, heating, and power system integrated with full-spectrum hybrid solar energy device

Abstract

This paper proposes a combined cooling, heating, and power system integrated with full-spectrum hybrid solar energy device containing molecular solar thermal system and solar water heating system to improve solar energy utilization efficiency. This system comprehensively integrates solar energy, fuel chemical energy and waste heat energy based on methanol decomposition to optimize energy utilization method. The thermodynamic models of components are established and the system evaluation indicators are presented. Based on a rated power of 834 kW, the thermodynamic performances under the design conditions were simulated and analyzed using Engineering Equation Solver, and the Sankey diagrams of energy and exergy flows were obtained in the respective cooling and heating modes. The results indicated that the solar energy share reaches 45.07%, and the energy and exergy efficiencies in cooling mode are 70.65% and 26.59%, respectively. They are increased by 1.52% and 1.92% in heating mode, respectively. The influences of various solar irradiation and power load ratio on system performances are discussed. The results indicate that the power load ratio and direct normal irradiance have positive impacts on energy and exergy efficiencies whereas they have negative impacts on solar energy share. Compared to the conventional methanol direct-fired system, the primary energy saving ratio and carbon dioxide emission reduction ratio of the proposed system reaches 16.20% and 16.14%, respectively.