Development of 10kW Proton Exchange Membrane Fuel Cell Combined Heat and Power System for Domestic Building Services

Cogeneration equipment based on hydrogen proton exchange membrane fuel cell has become one of the most economical and flexible low-carbon distributed power supply equipment, which has been widely concerned in scientific research and commercial promotion. The optimized integration of the system is the key step to realize commercialization. This paper focuses on the analysis of the technical status of the key components of combined heat and power (CHP) system and put forward the theoretical design method and operation strategy of each subsystem for a 10kW CHP system based on PEMFC. Firstly, for the air supply subsystem, it was found that when the back pressure valve was placed behind of the membrane humidifier, the air humidity of stack inlet increased gradually with the increase of current density, which presented a contrary trend from that at the front. The pressure difference inside the membrane humidifier was obviously reduced. Secondly, in addition to recovering the waste heat from coolant, an operation strategy that preheating the coolant by stored hot water was proposed, which helped to save the system cost due to coolant heater and improve the overall efficiency. The construction of the 10kW CHP system in this paper provides a guidance for the design and integration of CHP system based on PEM fuel cells.