Design And Analysis On Liquefied Natural Gas-Combined Cooling Heating And Power (LNG-CCHP) System

Along with the rapid development of marine economy in China, the development of uninhabited islands as an important part for the development of marine industry gets more and more attention, and the energy supply system of an island is the key to its successful development and operation. The development of solar power station has been greatly limited because of its low energy density, large covering area and difficulty in power quality control, so do wind power and tidal power. Thus, LNG-CCHP (Liquefied Natural Gas-Combined Cooling Heating and Power) system is the ideal choice.This paper discussed the current domestic and foreign research of LNG cold energy utilization system and gas CCHP system, put forward a new set of LNG cold energy power generation technology, analyzed natural gas power generation scheme of the island, coMPared different schemes of refrigeration and thermal storage, provided heat supply plan and living hot water production plan of an island, and finallyexplained the integration principle of power cycle with LNG cryogenic energy system and CCHP system. On this basis, This paper proposed some key basic data of the island and designd a set of island LNG-CCHP system, determined the size of the system and the main working parameters of the unit, analysed its operating flexibility, calculated the energy consumptionand various economic benefit of this system including environmental benefits, economic benefits, social benefits and security benefits.According to the results, the scale is as follows:2X60MW gas turbine installed capacity,50t/h steam load,20600RT district cooling load,27.71million kWh of central heating, central heating water scale of40000people,total equipment investment of LNG-CCHP system with vaporization capacity of15.6t/h is about0.836billion yuan. Generation benefit is0.105billion/year, payback period of the investment is about7.6years. The system energy utilization rate reached71.6%. In conlusion, besides stable energy supply, this system has a higher efficiency, better operating flexibility, greater economic, social benefits coMPared to the conventional ways, and has certain guiding significance for island CCHP system design.