A power and cooling cogeneration system using mid/low-temperature heat source

•This paper proposed an ammonia–water based power/cooling cogeneration system using waste heat.•Waste heat is utilized in a cascade way in power and cooling generation subsystems.•The condensation heat of turbine exhaust vapor is recovered by the refrigeration subsystem.•The interactions between the power and cooling generation subsystems are investigated.•Experimental results on the cooling generation subsystem are presented.

An ammonia–water based system for power and cooling cogeneration using mid/low-temperature heat source is proposed and investigated in this study. The proposed system consists of a Rankine cycle and an absorption refrigeration cycle. The high-temperature portion of waste heat is used for power generation, whereas the low-temperature part is used for refrigeration. In addition, the exhaust heat of the power subsystem is recovered by the refrigeration subsystem. Simulation results show that the equivalent heat-to-power and exergy efficiencies of the proposed cogeneration system can reach 18.6% and 42.0%, respectively. Compared with separate power and refrigeration systems, the proposed system consumes 17.1% less heat with the same output. The effect of turbine exhaust vapor temperature on system performance is investigated. An experimental rig of an absorption refrigeration system with a cooling capacity of 15 kW was built and tested. The proposed system was found to be capable of utilizing mid/low-temperature heat source more efficiently.