Life cycle assessment of renewable hydrogen for fuel cell passenger vehicles in California

Abstract

Renewable hydrogen (H2) fuel cell vehicles provide a promising pathway for decarbonizing transportation, but achieving high renewable content in H2 production presents a challenge when commercializing the technology. This problem is examined with case studies of potential renewable H2 projects in California that utilize policy instruments (solar net-metering) and technology (solar-wind hybrid) to maximize renewable content in electrolytic H2 production (100% and 75%, respectively). Based on life cycle assessment of the fuel and vehicle cycles, the life cycle carbon footprint of renewable fuel cell vehicles in these cases (105–149 g CO2-eq/vehicle km) is comparable to that of battery electric vehicles charged with California grid electricity (132 g CO2-eq/vehicle km), and about half that of compact internal combustion vehicles. The choice and integration of renewable electricity is the most important consideration for the life cycle carbon footprint of renewable H2 production, which ranges from 1.5 to 6 kg CO2-eq/kg H2. Linking renewable electricity production with transport, renewable H2 fuel cell vehicles can contribute toward California’s decarbonization goals.