storage
People seem to be forgetting the advantage of storing a high energy fuel that is liquid at room temperature. Hydrogen and electricity are difficult to store, and next to impossible to use in some applications like aviation. If you could produce a liquid fuel directly from water, carbon dioxide, and some form of renewable energy, you could also save a lot of the transportation and refining costs, with the added side benefit of CO2 capture. Instead of pumping a gazillion dollars and military into countries that hate us so that we can secure an oil supply, if we produce our own they can go back to wandering in the desert on their camels and leave us alone. Regarding farms, they are very inefficient, requiring vast quantities of energy input, usually in the form of petroleum, to plant, fertilize, harvest, transport and process and store, and the energy product in the form of biomass is difficult to use as an energy source. Only a small portion would be in the form of convenient oil or alcohols, and then there is the moral and practical hurdles on whether food should be used as fuel.
