In this work the preliminary results of the research activity regarding the development of a microcogeneration unit prototype based on a proton exchange membrane fuel cell for residential application have been presented. The combined heat and power (CHP) system, which has been designed to optimize the integration of commercial and precommercial components, is equipped with two fuel cell stacks, a natural gas steam reforming unit, a heat recovery unit, electrical devices such as batteries, dc/ac converters, and auxiliary components such as compressors and pumps. In order to evaluate the electrical and thermal energy production and to estimate the system efficiency, an energy analysis has been carried out by using a numerical model. The simulation results pointed out that the microcogeneration system is able to provide 2.2 kW(el) and 2.5 kW(th) with electrical and CHP efficiencies (refer to the low heating value) of 40% and 88%, respectively. Furthermore, the primary energy savings, achievable by using the cogeneration system in comparison with a separate generation of electricity and heat from a centralized power plant and conventional boilers, have been evaluated.