Next gen biofuels are ~1-2% efficient rather than <0.1%. At that point land isn't as much of a constraint. My money is on a biofuel/synfuel hybrid in the short

Next gen biofuels are ~1-2% efficient rather than <0.1%. At that point land isn't as much of a constraint. My money is on a biofuel/synfuel hybrid in the short term. Pyrolised/digested bagasse or some form of grass with electrolysed hydrogen used to modify hydrocarbons and increase energy yield.