[jandrese]

I think hydrogen for aviation is probably a dead end. I suspect the long term solution for aviation, at least long haul, is biofuels. Battery tech is edging into the realm where it could be used for short haul flights, but we have quite a ways to go before you'll be able to fly across the Pacific, or even Atlantic, on a single charge with reasonable passenger comfort.

[_hypx]

Biofuels are fundamentally not green. You might as well suggest we use fossil fuels forever.

[jandrese]

Biofuels today have issues, but there's no fundamental problem preventing them from being green. It's just a side effect of shoehorning them into our existing agriculture systems.

In the future when we have more solar power than we know what to do with during the day it may become economical to run the Sabatier reaction with hydrolyzed seawater and atmospheric CO2 to make methane, which can be burned in a lightly modified aircraft turbine.

[_hypx]

That isn't biofuel. That's synthetic fuel.

[traverseda]

What do you mean? The fuel itself should be carbon neutral, even if it requires extra energy to create. I don't see any reason you couldn't make carbon neutral bio fuel, although I'd net on syngas instead.

[_hypx]

Growing food and converting it to fuel is not carbon neutral. Farming is very resource intensive at the scales needed. In fact, it is literally the same idea as carbon capture, but via biology instead of synthetic. As a result, it is entirely a bad idea.