Energy Saving Analysis Of Combined Cooling, Heating And Power System

This paper aims at primary energy saving of CCHP. Based on previous research, it analyzes the primary energy consume of three kinds of systems: CCHP system, Combined Heating and Power system (CHP) with independent electric refrigeration, and independent Heating, Cooling and Power system (IHCP). It builds up the mathematical models for these three kinds of systems. From the view of primary energy consume and primary energy consume ratio, the factors which affect energy saving of CCHP system is studied deeply.Based on theoretical analysis, a formula for calculating parameter μ of CCHP is educed. It is concluded that variable μ is influenced by steam parameters of steam turbine, such as inlet steam pressure and temperature, extraction pressure and temperature, or backing pressure. And it is pointed out that variable μ essentially is the allocation proportion of energy among heating, power and cooling in CCHP system.After making a study of primary energy consumption and equivalent thermodynamic coefficient between absorption refrigeration and electric compression refrigeration systems, it concludes that energy saving performance in refrigeration system of CCHP is related to coefficient of performance of refrigerator and the parameter μ. According to the mathematical models that have been built, the ingredients of CCHP system are chosen, such as boiler, turbine and lithium bromide refrigerator. Then the total primary energy consumption of three kinds of system is compared. The study indicates that CCHP system is energy-saving compared to CHP system. And if the steam turbine is backpressure, the amount of energy saving is larger. The major factors which influence the energy saving of CCHP system are as following: ① capacity and steam parameters of steam turbine; ②coefficient of performance of refrigerator; ③heating load rate; ④average national heat generating electricity efficiency.This paper also analyzes the refrigeration of BCHP system from the view of primary energy. And it points out that the energy saving of BCHP system is high. So it is worth promoting and developing.