Synhelion and Zurich Airport have achieved a milestone in sustainable transport with the first-ever passenger bus at the airport fuelled by solar diesel. The vehicle is now operating in regular service using fuel produced at Synhelion’s DAWN demonstration plant in Jülich, Germany.

The solar diesel is fully compatible with existing engines and infrastructure, enabling immediate deployment without modification. The bus has been fuelled with a 190-litre barrel of the renewable blend, sufficient for around twelve days of operation.

Synhelion’s process uses solar heat to convert CO₂, water and biogas into syngas, which is refined into kerosene, diesel and gasoline. These fuels are nearly CO₂-neutral, releasing only as much carbon as is used during production.

Zurich Airport, which has supported Synhelion’s technology since 2020, plans to integrate solar fuels alongside electrification to decarbonise its fleet, particularly for vehicles unsuitable for battery operation.