Theoretical Study of a Building Cooling Heating Power (BCHP) System Driven by Solar Energy Based on Organic Working Fluid

Recently, BCHP systems as a kind of distributed energy resource present a great potential in improving energy efficiency and meeting multiple energy demands. Compared with traditional CCHP systems driven by fossil fuel, on-site renewable energy systems have more advantages in reducing carbon emissions. This paper proposes a new Building Cooling Heating Power system driven by solar energy with flat-plate solar collectors and R245fa as the working fluid. A thermal storage system is integrated into the system to store the collected solar energy and to supply heat when solar radiation is insufficient. By establishing the mathematical models of the proposed system we are able to conduct the numerical simulation of the system working in three typical operation modes around a whole year, namely the Combined Heating Power (CHP) mode in winter, the Combined Cooling Power (CCP) mode in summer, and the power production mode in spring or autumn. Results indicate that the system is able to operate continuously over a day, offering uninterrupted heating, cooling and power to building applications.