| CCHP based on micro turbines and small gas turbines is the main configuration form of distributed energy supply system. However, due to the poor part-load performance and the inflexibility when meeting user's energy demands which change dramatically, the efficiency and economic advantage of CCHP cannot be embodied often. Groundwater heat pump has the characteristics of high COP and good part-load performance, but it is restricted by factors such as water resources as well. In order to overcome the limitations of both technologies, the hybrid system which is the innovative integration of micro/small-tubine CCHP and groundwater heat pump has been proposed, and the analysis and research on it are carried out. The main contents of this thesis include:Firstly, the thermal, economic and emission models of main devices of CCHP system have been established. And the performance indexes of economic, energy saving, environmental protection and peak shaving in system comprehensive evaluation are given.Secondly, based on the optimal configuration method of full working conditions which considers the operational characteristics of equipments and can solve the difficulties in discrete optimization of equipment capacities and numbers at the design stage, a robust optimal configuration method of CCHP system is proposed to consider the uncertainty in energy demands.Thirdly, in regard to different types and sizes of two kinds of typical buildings in Beijing, the performance of economic, energy saving, environmental protection, peak shaving, electricity and natural gas price sensitivity of the usual seven CCHP schemes and five individual schemes are compared. Fourthly, in regard to the hybrid system, in addition to traditional following the electric load and the thermal load operational strategies, energy-saving-oriented is also introduced by selecting the energy saving rate of natural gas as objective function, and the influence of three strategies on system configuration, energy conservation and economy are discussed.Finally, the influence of uncertain energy demands on configuration and economical efficiency of hybrid system is also studied.The results show that the combination of micro/small-turbine CCHP and groudwater heat pump into a hybrid system can not only significantly improve the economical, energetic and environmental benefits of CCHP system and its flexibility coping with the typical user's energy demands which change dramatically and have high heat-to-power ratios, but also reduce more than half of the underground water extraction compared to the groundwater heat pump scheme. Among various energy supply schemes, hybrid system also has comprehensive advantages in many aspects, such as economic, energy saving, environmental protection, peak shaving, etc. Compared to the mode of "natural gas combined-cycle power plant plus gas boiler plus electric refrigerator", all the usual seven CCHP schemes and five individual schemes are not energy-efficient on natural gas utilization under traditional following the electric load and the thermal load operational strategies, but the hybrid system comprised of micro-tubine CCHP and groundwater heat pump can achieve energy saving under energy-saving-oriented. In addition, economic risks of the optimal configuration of hybrid system during the period of actual operation can be reduced after considering the uncertainty in energy demands.The hybrid system studied in this thesis can provide a new option to the development of energy utilization technology which complement between fossil energy and renewable energy.
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