مشخصات پژوهش

tThermo-economic analysis is applied to four combined liquefied natural gas (LNG) cold energy and (1)simple, (2) with internal heat exchanger, (3) regenerative and (4) dual-fluid ORCs. These power plantsuse geothermal fluid energy as low-grade heat source and cold energy of LNG as thermal sink. Also, aftervaporization in the organic fluid condenser, natural gas expands in a turbine to generate power. The effectsof operating parameters on energy and exergy efficiencies as well as total annual cost rate are studied forthe proposed systems. The operating parameters considered include inlet pressure of the organic fluidand natural gas turbines, condensing temperature of organic fluid, minimum temperature differencein evaporator, inlet temperature and mass flow rate of geothermal fluid. Moreover, optimal values ofoperating parameters of the system are evaluated to maximize the energy and exergy efficiencies andminimize the total product unit cost. The results show that the highest energy and exergy efficiencies areobtained for regenerative system and for the system with internal heat exchanger, respectively, whilethe simple system has the lowest total product cost. Furthermore, the maximum net power output isobtained using dual-fluid system at the same operating condition. Also, the higher and lower total costrate in optimum performance condition belong to dual-fluid and regenerative systems, respectively