Performance investigation of a solar-assisted hybrid combined cooling, heating and power system based on energy, exergy, exergo-economic and exergo-environmental analyses

摘要

This paper proposes a solar-assisted hybrid combined cooling, heating and power (CCHP) system that consists of an internal combustion engine, solar heat collectors, an absorption heat pump, a heat exchanger, and a thermal storage tank. On the basis of thermodynamic modelling and validation, the hybrid system was investigated from its energy, exergy, exergo-economic and exergo-environmental performances. The heat storage ratio and supplemental heat ratio were defined to consider the dynamic off-design operations and evaluate the contributions of thermal storage and supplement under the static design conditions, whose impacts on system efficiency and unit cost of products were discussed. For a specific case study, the energy and exergy analyses with the Sankey diagrams indicated that the hybrid system achieves annual energy efficiency of 76.3% and exergy efficiency of 22.4%. The unit costs of products were determined using exergo-economic analysis based on energy level, and the costs of products including and excluding carbon dioxide emission cost were compared. Compared to the conventional CCHP system without solar energy, the hybrid system saves 11.3% of natural gas to reduce carbon dioxide emission and shortens the capital payback period by 1 year.