Today solar-enabled aviation fuels provide the best opportunity for carbon natural flight – in the form of synthetic fuels. Modern planes use kerosene as fuel, which releases CO₂ into the atmosphere. A solution to the fossil CO₂ emitted is hydrogen fuel, which does not produce emissions. Hydrogen is a sustainable fuel and is now gaining attention as a possible aviation fuel alternative. Although hydrogen is promising, it won’t be able to deliver net-zero carbon emissions on its own. Synthetic paraffinic kerosene (SPK) is a bio-derived fuel that provides the means to deliver renewable hydrogen as aviation fuel due to its higher energy density and chemical composition.

While liquid hydrogen provides the opportunity for zero emission flight, challenges with cryogenic storage on the plane and fuel infrastructure mean that this option is decades away.

Hydrogen planes would require developments in propulsion, on-board storage, airport logistics, as well as redesign of the entire plane which would replace wing storage of fuel with cryogenic tanks. Planes would need to be refueled where new ways of transporting hydrogen to airports is required.  Hydrogen has the highest energy density of any fuel with more than double the energy density of conventional jet fuel. An airplane could achieve long range flight on pure hydrogen if it could be stored. SPK has a 1% higher energy density than conventional jet because of its chemical composition with more hydrogen per carbon atom. SPK provides a practical means to deliver renewable hydrogen as an airplane fuel. It has an improved energy density over conventional jet fuel and is available from low GHG emitting sources.

The carbon in biomass is saturated with hydrogen to make a pure straight chain hydrocarbon to achieve a higher energy density than conventional jet fuel.

Click here to read the full article on why “Hydrogen Won’t Fly Today”.

Prepared by Stefan Unnasch and Kathleen Dailey, Life Cycle Associates, LLC