Both companies have been using the Chevrolet Equinox-based HydroGen4 SUV in Berlin as part of an ongoing trial. Enertrag’s hydrogen station in the city’s Prenzlau district can now supply green hydrogen gas to Total’s refilling stations, for use in the government-supported Clean Energy Partnership.

Opel said the project marked the next step in the development of a refuelling infrastructure for hydrogen fuel cell vehicles. Although hydrogen itself is abundant, the process of mass-producing it is energy-intensive, which undoes some of the carbon reduction from a fuel cell vehicle.

Hydrogen fuel cell vehicles are driven by an electric motor and make their own electricity using a chemical reaction, which means they produce no CO2 emissions at point of use, with only water vapour coming out of the tailpipe.

Honda has also invested in renewable energy to power its hydrogen refuelling stations. The carmaker opened a solar-powered station in Japan last month.