In a fossil-free world, there's hope to continue flying

Via 3E Intelligence , a paper on Alternate Fuels for use in Commercial Aircraft. This paper gives a good overview of the short-term and longer-term solutions to reduce carbon emissions from air transport, and eventually, to keep flying in a world without fossil fuels.

The short-term option is synthetic fuels from carbon feedstocks (mainly coal and natural gas). In combination with sequestration, this process could lead to a reduction in CO2 emissions.

In a medium term, these synthetic fuels could then be blended with biofuels (0-50%).

Longer term solutions could be based on hydrogen produced by solar or nuclear fusion energy. Or we could harvest methane hydrates and use them directly as low carbon fuel, or convert the methane to liquid hydrogen wh ile sequestering the CO2.

There are enormous technical difficulties to overcome and the overall lifecycle impact is still largely unclear, but the paper demonstrates that some flying will still be done in a future fossil-free era.