A review on global warming potential, challenges and opportunities of renewable hydrogen production technologies

This review compares global warming potential of renewable hydrogen production technologies including wind-and solar PV-powered water electrolysis, biomass gasification and biogas reforming based on 64 hydrogen production cases compiled from the literature. Unlike many previous studies, this review discusses the cases from various countries, while selecting the production technologies that have potential of commercialisation. Among the four reviewed technologies, wind electrolysis performed the best in global warming impacts (1.29 kg CO2 eq/ kg H2), whereas biogas reforming technology performed the worst (3.61 kg CO2 eq/kg H2). Key factors that contributed to most of the impacts were found to be materials used for construction of wind-and solar-electricity generation system for both wind-and solar PV-powered electrolysis, and energy consumption during gasification processes for biomass gasification, while methane leakage during biogas production had the highest contribution to the impacts of biogas reforming cases. On average, the renewable hydrogen cases demonstrated 68-92% lower global warming potential when compared to conventional coal gasification and natural gas steam methane reforming systems. Increasing demand for renewable hydrogen and possibility of hydrogen being integrated into existing natural gas networks highlight the important role of renewable hydrogen production in the future.

Automated summary

This study compares the global warming potential of different renewable hydrogen production technologies based on 64 cases compiled from the literature. Wind electrolysis performed the best while biogas reforming performed the worst in terms of global warming impacts. Factors such as materials used for construction and energy consumption during gasification processes were found to contribute to the impacts. Renewable hydrogen cases showed significantly lower global warming potential compared to conventional coal gasification and natural gas steam methane reforming systems. The increasing demand for renewable hydrogen and its integration into natural gas networks highlight the importance of renewable hydrogen production in the future.