Thermodynamic assessment of a new PTC operated polygeneration system for fresh water, cooling, electricity and hydrogen production for a residential community

Abstract

The current study aims to design a new parabolic trough collector (PTC) operated polygeneration system to produce freshwater, hydrogen, cooling, and electricity in a residential society. Dowtherm A (a heat transfer fluid) is used to transfer the heat from PTC to the Organic Rankine Cycle, which is used to produce electrical power. The produced electrical power is utilized in three different ways, namely, to run the home appliances, to produce hydrogen (via water electrolysis), and to produce cooling (through a vapor compression cycle). The cooling produced by the vapor compression system is utilized to preserve the food, milk, and to operate the freezing desalination process. Effects of several factors, such as direct normal irradiance, evaporator temperature, and seawater inlet temperature, have been analyzed on the overall system behavior. Thermodynamic study results show that for a PTC area of 2000 m2, an electrical output obtained is 72 kW, the cooling rate is 112 kW, and the mass flow rate of fresh water produced is 18.4 l/day and 10.8 kg/day of hydrogen for mean solar irradiation of 700 W/m2. The energy efficiency of the system is found to be 17.5%, and the exergy efficiency of the system is around 10.9%.