Design and performance analysis of a resorption cogeneration system

As a type of traditional cycle for electricity generation, the main limitation of the Rankine cycle is the endothermic process for the evaporation (e) of water (w), which does not always fit very well with the trend of the heat source. The Kalina cycle can make up the efficiency loss by using a working fluid of water-ammonia, which has a variable heating process by adjusting the concentration of ammonia in the water absorbent. Based on the Kalina cycle, a combined power and refrigeration generating cycle has been proposed by Goswami, which generally has reasonable exergy efficiency but suffers from the low energy efficiency for the refrigeration process. In this study, a new type of the resorption cogeneration system is designed, which features a comparable electrical generating performance and much higher refrigerating performance than the Goswami cycle. The performances are analysed, and the exergy of the system is calculated. When the system works without heat recovery, η El and COP ref range between 0.072–0.126 and 0.33–0.53, respectively; when the heat recovery cycle is included, in which the thermal capacity of the metal and the adsorbent of the adsorber are both considered, the η El and COP ref range between 0.095–0.158 and 0.416–0.691, respectively. The highest value exergy efficiency of the system is ∼0.82, which is an improvement by 50% when compared with that of the Goswami cycle. Copyright , Oxford University Press.