An innovative conversion of a district heating water-tube boiler for cogeneration of electricity and heat

The primary goal of combined heat and power (CHP) generation is to increase the overall efficiency of the process, which is primarily achieved by reducing energy losses associated with a single generation. The research aims to verify the possibility of adapting the district heating hot water cycle into the CHP plant through thermodynamic and techno-economic analyses. A complete layout of the innovative conversion as well as technical limits and possibilities are discussed. The manuscript presents a method of obtaining cogeneration conditions, therefore simultaneous production of heat and electricity in a cycle where the heat source is a water boiler. The solution from the thermodynamic and financial point of view has been proven on the example of the WR25 stoker boiler, for which the system produces 0.5 MWe with a simultaneous increase in the efficiency of the unit and no additional restrictions on its operation. At the same time, methods for further increasing the electric power without additional modernizations in the system were presented.