How the boundaries of the supply chain affect climate profile: The case of renewable electricity and green hydrogen for Italy and the UK

Green hydrogen obtained from renewable electricity can play an essential role in the decarbonization of different sectors. The reliability of the data used to model the entire supply chain is a crucial parameter in Life Cycle Assessment. In this study, the authors show how photovoltaic and wind electricity supply chains influence the carbon footprint of green H 2 . While most published studies rely on default datasets from commercial libraries, the current work exploits the actual supply chain of the PV panels and builds an updated average European wind turbine supply chain. The updated values for PV-based H 2 , experiencing a 40–60% reduction, are 2.7 and 1.8 kg CO 2 eq./kg H 2 for the UK and Italy. The carbon footprint of UK offshore wind-based H 2 can be reduced up to 24% and get close to 0.6 kg CO 2 eq./kg H 2 . The findings emphasize the sensitivity of the final climate profile generated by the processes upstream of the electrolysis system. • The updated supply chains of PV and wind electricity are built. • The updated carbon footprint of PV-based H 2 reduced up to 45–60%. • The updated GWP of PV-based H 2 is 2.7 and 1.8 kg CO 2 eq./kg H 2 in the UK and Italy. • Wind-based H 2 production can result in less than 1 kg CO 2 eq./kg H 2. • A 19 and 24% GWP reduction is achieved for offshore scenarios in Italy and the UK.