Turning sunlight into fuel: SWISS is first airline to use fuel manufactured using solar energy in flight operations
July 28, 2025
Swiss International Air Lines (SWISS) has taken delivery of “solar fuel” manufactured by Synhelion at Hamburg Airport.
The introduction of clean-tech company, Synhelion’s “solar fuel” in SWISS’s operations marks a “genuine milestone,” according to SWISS CEO, Jens Fehlinger.
“We are not just talking about the future; we are helping to shape it and proud to lead the way.”
Synhelion’s synthetic crude oil was delivered from its DAWN production facility to a refinery in Northern Germany, where the oil which had been manufactured using solar energy, was processed into certified jet fuel. The fuel was then fed into SWISS’s flight operations infrastructure via the fuel supply system at Hamburg Airport.
Small volume marking a significant milestone
This initial delivery of a 190-litre barrel of synthetic crude oil represents around 7% of the fuel needed for a Hamburg to Zurich flight.
Fehlinger noted that the initial supply wasn’t huge in terms of volume. However, it confirms that Synhelion’s technology works and that the fuel can be seamlessly integrated into existing refinery processes.
According to Synhelion, its solar fuel can reduce CO2 emissions by up to 99% compared to fossil fuels. The company also states that solar fuels are the most economical way of producing sustainable synthetic fuels. The goal is to reach production costs below €1 per litre.
Reinforcing that “this is the first time that solar fuel has been used in civil aviation”, Fehlinger added: “We are truly proud to be playing such a pioneering role, in partnership with Synhelion, in driving and developing this vital new technology for a more sustainable aviation sector.”
Strategic partners in turning sunlight into fuel
The two companies have been strategic partners since 2020. “It started with a vision to turn sunlight into fuel,” said Synhelion co-founder and CEO, Philipp Furler.
“In 2022, we demonstrated at a test facility that renewable synthetic fuels could be produced from solar energy, water and CO2.”
In 2024 DAWN was launched as the first solar fuel plant. “Since then, solar fuels – including jet fuel, diesel and gasoline, have been produced on an industrial scale and now we have delivered our solar fuel to SWISS,” Furler continued.
Scaling up solar fuel production
Plans are now afoot to scale up production of the solar fuel. The facilities and production capacities needed to ensure the fuel can be produced in line with demand are now being developed to permit a commercial market entry for the fuel from 2027. Synhelion and SWISS are now working together to drive forward the sustainability certification of the production process and the fuel in accordance with EU Renewable Energy Directive.
The directive stipulates that sustainable synthetic fuels much achieve a reduction in greenhouse gas emissions of at least 70% compared to conventional fossil fuels.
Furler underlined that while the delivery of the first barrel to SWISS may be a symbolic action, “it’s also a concrete one.” This milestone, he said, “brings us one step closer to globally scaling up our solar fuel technology. And we’re very grateful to have such invaluable support from our partners at SWISS and the Lufthansa Group as we continue on this journey.
“Together we are making solar fuels fly.”
