| The investigations on heat engine driven heat pump utilizing natural gas are now come in for people's attention with the vast popularization use of natural gas in our country and the power crisis caused by large use of electric air conditioning. Employing gas engine to drive heat pump is better choice compared to Stirling engine, turbine and gas turbine under today's condition. After introduce the operating principle and system characteristic of GEHP (gas engine-driven heat pump), the author discuss the application feasibility in China. The author deems that the using of the GEHP in northeast area of China should using gas boiler for assistant heating up, moreover, the operating mode should in alternation manner. In Yellow River valley the GEHP should be designed in heating mode, but in Yangtze River valley we should take air conditioning mode. The using of GEHP in South China region can reduce the power intensity in summer.For thoroughly know the energy saving effect of GEHP, The thermodynamics analysis is processed with the first law of thermodynamics, exergy theory, energy grade theory and thermoeconomic method. The results show, when heating, the primary energy ratio of GEHP is 1.76 and exergy efficiency is 29.12%. Which are higher than electric driven heat pump, gas boiler, coal boiler and electric boiler. The energy grade theory analysis results also show that the energy utilization of GEHP is comparatively reasonable. Exergy cost of GEHP is 11.2 yuan/GJ by thermoeconomic method, which is much lower than the heating price nowadays. All the results indicate that GEHP has upper thermodynamics perfect than other heating equipment, and is of high efficient energy saving technology. Among these method, energy grade theory considering the using of anergy. Because the improvement of coefficient of performance of the GEHP mainly due to the use of waste heat from surroundings, we suggest that we should use energy grade theory to evaluate the performance of heat pump.The author build and improve GEHP's experiment set to validate the feasibility of this technology. Noise of the GEHP debase obviously after upswing. The results show that GEHP is of high efficiency energy saving technology. The primary energy ratio is between 1.13-1.79 under experimental condition. When the gas engine speed down, the efficiency of gas engine go up, but the COP and the PER drop. The descendant value is small and keeps stable in large area. All this indicate that GEHP has good part load characteristic and fit for variable speed adjustment.Industrial ecology investigates the energy flow, substance flow and value flow among each subsystem using whole system viewpoint. Cogeneration system mainly investigates the relationship and the conversion of multi-kind energy flow among each components of a system. What their aim are to get the best purpose. So there are much analogy exists between them. The ecology investigate viewpoint, life cycle assessment and energy redundancy degree will develop the theory of cogeneration, while the exergy analysis, energy grade theory and thermo-economic method also enrich the evaluation method of industrial ecology.A gas engine driven heat pump cogeneration system for combined heat, cold and power production is put forward and represented in this paper. Load matching between gas engine and compressor, gas engine and generator is processed. The rule formula X1 and X2 are defined. X1 indicates the load matching of gas engine and compressor, X2 indicates the load matching of gas engine and generator. And the flow matching between refrigeration of the compressor and fuel of the gas engine is also processed. To evaluate the thermodynamics perfect of this system, the concept of standard gas consumption is defined. Analysis of the system indicates that the primary energy ratio of this system is 1.85, which is double than that of the conventional separated production system, and the cogeneration system saves about 57% standard gas consumption in comparison of the conventional separated production system.
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