ETH-Zurich spin-off Synhelion has raised CHF 22 million (US$23.6 million) in another financing round. The funds were primarily provided by existing investors and selected new strategic investors, including Swiss International Air Lines (SWISS). The proceeds of the investment round will accelerate the company’s growth and support the scaling and commercialization of Synhelion’s solar fuels technology.

Synhelion has developed a solar thermal process for the production of syngas, which is then used in standard industrial processes to synthesize liquid fuels, such as kerosene, gasoline, or diesel, that are compatible with conventional jet engines and internal combustion engines.

Synhelion is developing two pathways to solar fuels:

• Redox splitting. The thermochemical splitting of CO₂ and water in a two-step redox reaction yields carbon-neutral fuels. The thermochemical reaction to turn CO² and water into syngas takes place at 1,500 °C. This ultra-clean solar fuel closes the carbon cycle. It uses the same amount of CO₂ for fuel production as is released during fuel combustion.

• Solar Upgrading. Industrial reforming technology is paired with key innovations of Synhelion to enable the energy-efficient production of solar fuels. Solar heat is used to convert a mixture of methane, CO₂, and water into syngas, which is then processed into any type of fuel. The solar receiver delivers the required process heat of 800 to 1,200 °C to trigger this chemical reaction.

Sustainable fuels are becoming increasingly significant as the mobility sector strives to decarbonize, not least to meet climate targets of net zero carbon emissions by 2050.

By successfully producing syngas on an industrial scale using solar heat, Synhelion reached its last decisive technical milestone for the industrial production of sustainable solar fuels in August 2022. Shortly after, Synhelion started construction of DAWN—the world’s first industrial plant to produce sustainable fuels using solar heat. (Earlier post.)

This additional investment will enable the company to build DAWN and take the next steps in scaling its fuel production, including the technical design and construction planning of its first commercial plant in Spain.

SWISS and the Lufthansa Group are trusted strategic partners of Synhelion. SWISS’ investment in Synhelion now extends this strategic collaboration, underpinning its commitment to focusing on carbon-neutral flying and to bringing sustainable solar aviation fuel to market. Acting as a key launch partner of Synhelion, SWISS will be the first airline to use solar kerosene. Subsequently, Synhelion’s fuel will be made available across the industry.