Yes it is certainly viable. Far too many people think efficiency is going to be the deciding factor, but in reality we already have tons of energy that goes to

Yes it is certainly viable. Far too many people think efficiency is going to be the deciding factor, but in reality we already have tons of energy that goes to waste, and it is only going to get larger with intermittent renewables. Over provisioning of renewables seems to be the current best option to deal with baseload demands from intermittent renewables, which will mean that the cost of surplus non-peak energy is going to trend toward $0/kWh. In the end, who cares if it takes 150kWh to make 50kWh of fuel if that 50kWh of fuel only costs $1? I'm 100% sure most trucking companies won't give a shit. This all would mean that efficiency doesn't really matter anymore, but rather the practical characteristics of the fuel. Liquid fuels, and many easily compressed fuels, are amazingly practical. Natural gas is already a viable fuel for many trucking applications, and synthesized methane is incredibly easy. But synthetic diesel and butane are also within the realm of possibilities.