Environmental impact assessment on polymer electrolyte fuel cell co-generation system, lithium-ion battery, and photovoltaic hybrid system combination and operation, considering performance degradation

In recent years, fuel cell co-generation systems (FC-CGS) have attracted attention for contributing to the environment and are becoming increasingly popular. Considering the current situation, technical specifications for general FC-CGS environmental impact assessments have been published by the International Electrotechnical Commission (IEC) Technical Committee 105 Working Group 14 (TC105WG14). Additionally, several combinations of renewable energy systems, energy storage, and energy-saving technologies have been proposed to obtain more environmental benefits. In this study, several scenarios for combining a polymer electrolyte fuel cell co-generation system (PEFC-CGS) with a battery and PV were created, system operation was discussed, and an environmental impact assessment was conducted. The evaluation was based on IEC standards, considering performance degradation during the usage phase. As a result, it was found that a system in which PEFC-CGS operated in load-following mode, combined with battery and PV, could reduce global warming potential (GWP) by about 36%. There was almost no difference in the PEFC-CGS degradation rate owing to the difference in the operating methods. However, the battery degradation rate showed approximately a 45% difference depending on the scenario. In addition, an environmental gain of ${\eta }_{eco-gain}$ was proposed that expresses the reduction rate from the BAU scenario. Finally, a sensitivity analysis was conducted by changing the weather conditions. The results showed that even when solar radiation was varied, eco-gain was much better than when PV was not installed.