Abstract: Aiming at the serious pollution caused by burning of the fossil fuel, to increase the proportion of clean energy in primary energy consumption in China, a new Organic Rankine Cycle system utilizing the solar energy and the cold energy of liquefied natural gas (LNG) was constructed to solve the problem of serious environmental pollution caused by fossil fuel combustion. The results showed that: the optimal net output power and thermal efficiency were obtained when the two cycle take the best evaporation pressure 2.8 MPa and the best evaporation temperature 371 K, the values are 81.46 kW and 20.88% respectively; when the evaporation pressure of two cycle is 3.0 MPa and the evaporation temperature is 371 K, the exergetic efficiency reaches the peak value 53.43%; the maximum exergy loss of the system is in the heat exchanger components, the exergy efficiency of solar collector is lower. According to 90% power generation efficiency and 1 yuan/(kW·h) electricity price, the system can bring economic benefits of more than RMB 530 000 per year. Compared with the same coal⁃fired power generation, it has the effect of SO2 emissions by 13 939 kg/a and CO2 emissions by 462 000 kg/a, which can achieve the effect of energy saving and emission reduction.

Key words: Solar energy, Liquefied natural gas, Organic Rankine Cycle, Exergy, Thermodynamics

摘要： 针对化石燃料燃烧时对环境造成严重污染的问题，为增加清洁能源在我国一次能源消费中所占的比例，构建了太阳能和LNG冷能联合使用的有机朗肯循环系统，通过热力学性能和㶲损分析了建立的循环系统。结果表明，当循环Ⅰ、Ⅱ的蒸发压力为2.8 MPa、蒸发温度为371 K时，系统存在最大净输出的功和热效率，其值分别为81.46 kW、20.88%；当循环Ⅰ、Ⅱ蒸发压力分别为3.0 MPa，蒸发温度为371 K时，最大㶲效率为53.43%；换热部件的㶲损最大，集热器的㶲效率较低；按90%发电效率、1元/（kW·h）电价计算，系统年均可带来超过53万元的经济效益，与相同燃煤发电量相比，可减少SO2排放量13 939 kg/a和CO2排放量462 000 kg/a，具有节能减排的效果。

关键词: 太阳能, LNG, 有机朗肯循环, ?, 热力学