Energy input is the other. It takes at minimum the combustion energy to reconfigure the molecules but most of the processes happen at high temperature and pressures which takes energy to do.
I understand input is an issue, but why aren't renewables cheap enough to solve the energy input part of the problem? Don't solar panels cost next to nothing nowadays?
How much must renewables decrease in cost in order for such fuels to be economically competitive?
FooBarWidget|3 years ago
How much must renewables decrease in cost in order for such fuels to be economically competitive?