Energetic Performance Assessment of Different CHP-CHCP Configurations of a 15 kW Micro-CHP Plant through 1D Thermo-Fluid Dynamic Simulation

The exploitation of renewable energy sources and the widespread adoption of primary energy saving techniques have been recognized as key solutions to face climate changes. These solutions are pushing the transition from a centralized power generation system to a distributed polygeneration system which is suitable to meet simultaneous heating, cooling and electricity demand. However, small scale polygeneration plants do not ensure effective primary energy and cost savings without a proper sizing and operation of the plant. Furthermore, a customized configuration of the waste heat recovery system adopted for cogeneration purposes can be equally important. Therefore, starting from the experimental data concerning a 15 kW micro-CHP plant previously designed and prototyped, the paper addresses the energetic characterization of different CHP-CHCP configurations of the same plant through 1D thermo-fluid dynamic simulation. In particular, as the achievable primary energy saving depends on the thermal power recovered and actually exploited, and so on the temperature level which characterizes the user's thermal demand, three different configurations of the waste heat recovery system were analyzed and the plant energetic performance estimated. Each configuration, delivering thermal power at different temperature level, could be useful to meet thermal and cooling demand from different user. This paper also provides useful results for the design of CHP systems which are capable to ensure a reasonable matching between the temperature level required by the user and that provided by the plant. In this way, primary energy savings are more easily achievable even when a micro-CHP application is considered.