Comprehensive performance assessment of a novel biomass-based CCHP system integrated with SOFC and HT-PEMFC

The combination of biomass gasification and fuel cell is a promising way to enhance the system energy efficiency and decrease the fossil fuel consumption. In this study, a new biomass-based combined cooling, heating and power (CCHP) system considering high temperature proton exchange membrane fuel cell (HT-PEMFC) and solid oxide fuel cell (SOFC) is proposed. Syngas from biomass gasifier is utilized by SOFC and HT-PEMFC for power generation, waste heat derived from SOFC and HT-PEMFC are recovered by ORC and absorption chiller for electricity and cooling production, respectively. Energetic, exergetic, economic and environmental investigations are performed to illustrate system comprehensive performances. The results demonstrated that power generation ratio of SOFC to HT-PEMFC is 2.32, exergy and energy efficiency of CCHP system are 25.06% and 49.48%, respectively. Levelized cost of production and CO2 emission rate of multi-products are 0.069$/(kW·h) and 0.673kg/(kW·h), respectively. Moreover, steam to biomass ratio and equivalent ratio show different effects on system performances due to the distinction of syngas composition. Operating temperature of SOFC has a great influence on system exergy and energy efficiency, with increasing by 11.18% and 16.97% respectively. In general, this novel system provides a new pathway for integrating biomass with different fuel cell technologies.