The Research On Schemes Of Capacity’ Selection Of Building Cooling Heating And Power System

Combined cooling heating and power (CCHP) system can be applied for theenergy cascade utilization, with the advantages of high energy utilization ratio and lesspollutant discharge. Meanwhile, it plays an important role on the adjustment of nationalenergy structure and remission power shortage in summer. In this paper, for three samebuildings in different cities, under two kinds of design ideas of fixing power based onheat and fixing heat based on power, three capacity-increase projects are put forwardand analyzed through simulation respectively.Micro-gas turbine is applied as power generation assembly of CCHP system,exhaust gas type lithium bromide absorption water chiller(heater) is applied forwaste-heat utilization. The cooling, heating and power loads of the buildings aresimulated, and the all-condition performance models are built through curve fitting.Then the models of the systems are built and are applied to simulated different projects.Firstly, this paper studies at different influence of the design idea fixing powerbased on heat and fixing heat based on power to the economy and energy saving ofBCHP. It shows that the design idea fixing power based on heat is moreenergy-efficient, and the design idea fixing heat based on power is more economical.Secondly, on the basis of primary projects’ running, this paper puts forward thefollowing several methods to improve the operation of BCHP. Direct-fired type lithiumbromide absorption water chiller (heater), gas-fired boiler combining with centrifugalchiller, exhaust gas and supplementary-fired type lithium bromide absorption waterchiller (heater) are applied as peak shavers respectively in those projects.The projects are rated from two aspects of energy saving performance andeconomic efficiency, and the optimal design schemes are put forward for different cities.According to the simulation results, the design idea fixing power based on heat andthe direct-fired unit and supplementary-fired unit as peak shavers are fitter if the coolingload is equal to and greater than heating load. The design idea fixing heat based onpower and gas-fired boiler combining with centrifugal chiller, are fitter if the heatingload is greater than cooling load.