Operation Strategy Analysis For Hybrid Heating System

Building efficiency is a social topic issue, rational utilize of the renewable energy isone way to reduce the energy consumption of buildings. Using heat pump to recoverwaste heat is of great significance in energy saving and environmental protection, heatpump heating system is now considered a viable alternative to conventional heatingsystem. For the outlet water temperature of the heat pump is lower than therequirement of radiators, heat pump must be coupled with conventional heatingequipment.In the hybrid heating system, heat pumps are adopted to afford the basic heatingload of the system, conventional heating equipments are deployed for peak loadcompensation and regulating the supply water temperature. In order to improve theenergy efficiency of the system, the cascade mode is suggested between heat pumpsand conventional heating equipments. The energy efficiency of the hybrid heatingsystem is affected by the supply water temperature, and the supply water temperatureis the function of the outdoor temperature. Therefore, the energy efficiency of thehybrid heating system can be improved by regulating supply water parameters and theoptimal operation strategy.In order to provide reference for scientific operation of the hybrid heating system, itis necessary to research into the operation strategy of the hybrid heating system.Firstly, the forecast modal of the heating parameters in different outdoor temperatureswas established. Secondly, the performance model of the system and the evaluationmethodology of the hybrid heating system were established. Finally, the operationstrategy of a hybrid heating system was analyzed.Firstly, a test was conducted on a radiator heating system, the relationship betweenheating parameters and outdoor temperature were analyzed. The results indicated thatthere is a linear relationship between the average temperature of the radiator andoutdoor temperature, which provide the theoretical basis to forecast the heatingparameters in different outdoor temperatures.Secondly, on the basis of the hybrid heating system studied in this paper, theperformance models of the system components, including heat pump, gas boiler andwater pump were established respectively. Then, the performance model of the system was established on the basis of the performance models of the system components,and the evaluation methodology was studied on the basis of the contrast betweenhybrid heating system and conventional coal-fired boiler heating system.Finally, the operation strategy analysis for a hybrid heating system in Xi’an wasperformed. First of all, the heating load of the buildings was simulated by Trnsys, andthe relationship between heating load and outdoor temperature was obtained. Then,the computation modal of each equipment was established, and the optimal controlfunction of the system was determined. At last, the operation strategy of the hybridheating system in different outdoor temperatures were obtained, and the advantagesand disadvantages of the hybrid heating system was evaluated in economicalefficiency, energy saving and carbon emission reduction.