Economic and environmental assessment of phosphoric acid fuel cell-based combined heat and power system for an apartment complex

Economic and environmental potential of medium-scale combined heat and power (CHP) systems in the residential sector was assessed by introducing a 400 kW_el-scale phosphoric acid fuel cell (PAFC)-based CHP system into an apartment building in New York City. Simulation-based analyses were carried out under two different CHP operation strategies; electrical-load-following (ELF) and thermal-load-following (TLF). Technical and economic analyses indicated that ELF would be the appropriate operation mode for this CHP application. Economic analysis indicated that the CHP/ELF system operation could economically benefit users within 10 years under the present grid prices in New York City. However, because the CO₂ emission factor of the NY grid is very low (300 g/kWh), the CHP/ELF system operation would increase CO₂ emission. Achieving carbon neutrality in this application thus requires improvement in the utilization ratio of recovered heat.