[dkjaudyeqooe]

If you talk to Airbus, the current plan is hydrogen, which is emission free, besides water. Since you can extract it from water by electrolysis, there is an essentially endless supply, assuming you have endless clean electricity.

[ogre_codes]

Hydrogen power is fundamentally a power storage technology. It makes sense to use H2 for that. I've seen some technology that transforms CO2 into jet fuel which is another somewhat carbon neutral technology.