Thermodynamic analysis of a domestic hot water and electricity cogeneration system using an internal combustion engine and an organic Rankine cycle

Abstract

This work presents a thermodynamic analysis of a cogenera-tion system with the capacity to generate electricity and DHW (domestic hot water). The system is integrated by a Diesel engine, an ORC coupled to the exhaust gas recovery and an DHW system coupled to the radiator heat recovery. To eval-uate the thermodynamic viability of the system, the mass and energy models are established based on the first law of ther-modynamics. The results indicate an increase in the total elec-trical efficiency of the system of 2.75% from the use of waste heat contained in the engine exhaust gases to activate the ORC and a total power of 1,079.58 kW. The electrical energy gener-ated can meet the demand of 2,879 homes, while the thermal energy can supply hot water to 1,846 homes.