摘要

The popular operation mode of following thermal load often causes power surplus and efficiency decrease in CCHP (combined cooling, heating and power) systems at part load. CAES (compressed air energy storage) is thus one of the appropriate technologies to improve CCHP part-load efficiency through peak load shifting. However, the output power of CAES is possibly not high due to low temperature of the compressed air entering air turbine. In view of these problems, this paper proposed a gas turbine based CCHP combined with solar thermal energy and compressed air energy storage (S-CAES). The off-design models of gas turbine based CCHP and S-CAES were built. The merits and flaws of two different control strategies of S-CAES were analyzed. The characteristics of the proposed system indicate that the energy efficiency and exergy efficiency are both higher than those of the CCHP system without S-CAES. The performances of S-CAES are mainly influenced by the designed parameters, load distribution of demand side and the capacity of gas turbine. A case study of the proposed CCHP with S-CAES system in an 180000m(2) hotel building located in South China shows that the optimal power capacity of S-CAES comes to 435 kW; and energy efficiency increment gains 1.015% in comparison with a corresponding optimized CCHP system without S-CAES.