Generating some sort of fuel is probably the best idea indeed. Hydrogen is often suggested because it's easiest to create out of water, but it's also hard to store. Ethanol is definitely easier to store, but requiring a lot of biomass is definitely a bit of an obstacle.
Genuine question - how many engines can run on straight ethanol? Are there any negative consequences for running straight ethanol in an engine expecting gasoline?
> Some sort of cheap long term storage would really help a lot.
Run a still to make ethanol from waste biomass. Store it (don't drink it!!) and use it to fuel a generator in the winter.
I'm only half joking.