Economic Analysis Of Combined Cooling Heating And Power System Under Multivariate Factors

With the great reform of electricity market around the world, increasingly stringent pollution emission standard has been set by many countries, and with the price increase of end-consumer energy, distributed CCHP (Combined cooling, heating and power) system has been getting more and more attention. CCHP system can improve energy utilization ratio, reduce pollutant emissions, save energy, and simultaneously can be combined with solar, wind and other renewable and clean energy. It can effectively alleviate the obvious contradictions between economic development and energy and environment, which has a broad market prospect. Especially, with the breakthroughs of technological development and utilization of Chinese shale gas and gas price decline, gas-CCHP system will be better than separate generation system in economy, which will lead to a large-scale application situation of CCHP system.Economic benefits is the best concern for users and investors of CCHP system. This paper focuses on research about economic analysis of CCHP system under multivariate factors, and main contents are as follows:(1) The paper introduces the classification and principle of CCHP system, and introduces principle, features, mathematical model and application of main equipment which includes the mover, absorption refrigerator, boiler, electric compressor and direct-fired absorption chiller. Meanwhile three typical CCHP systems are given, which have been widely used.(2) The economic evaluation index of CCHP system has been proposed, and the optimizing method is proposed with an optimization target which is seeking the minimum of total cost in operation time. The optimizing method, based on equipment operation constraints, load balancing constraints and the security and stability constraints, is described in detail.(3) Load fluctuations, changes in power and gas price, subsidy policy, new energy, control strategies, grid interconnection and energy storage are analyzed, and the effects of change in various factors of the economic indicators are studied. By modeling the case of a Beijing hotel, the change regulation of economic indicators under multivariate factors is analyzed. With rising electricity prices, lower gas prices, increased subsidies or reasonable electricity price, the incremental payback period may be shortened, while adding new energy sources or energy storage, load demand and structure of the system and new equipment costs must be considered. Finally, based on the aforementioned optimization model and algorithms, a CCHP system economic analysis software has been developed, which can analyze the influence of CCHP system under different factors.