Burning hydrocarbons peeks out at something like 40% efficiency. Yet we are only now getting to the point where EVs have the same range as ICE vehicles, even though the battery->motor conversion is something like 90% efficient.
Why is that? Because the amount of energy that can be stored in batteries is MUCH lower than the amount of energy released from burning fuel.
Transport needs to carry all of it's energy with it (or, have something like a 3rd rail to provide energy).
That's the argument for biofuels in the future. Not that you can't replace 99% of transport with electricity, but rather some forms of transport require a lot of energy.
We are JUST getting to the point where batteries have enough density to power a prop plane for ~ 1hour worth of flight.
We are no where near the energy density where a cargo ship could sail from china to the US or for international flights.
One alternative to biofuels is hydrogen from something like electrolysis.
One thing I think we'll both agree on. Ethanol for cars/trucks is a terrible idea. EVs are the future there.
https://www.power-eng.com/2020/07/08/power-to-gas-examining-...
https://en.wikipedia.org/wiki/Fischer%E2%80%93Tropsch_proces...
The advantage of synthetic fuels over biofuels is that you can get a lot more fuel out of 100 hectares of solar panels than 100 hectares of crops, because plants are very inefficient at capturing solar energy as useful chemical energy. The advantage of biofuels over synthetic fuels would be lower capital costs. Biofuels have an advantage while non-fossil fuel demand is low, but they can't scale as well.
Since artificially capturing CO2 from the air is expensive and inefficient so far, an attractive hybrid path combines biomass and electrolytic hydrogen to make methane or heavier hydrocarbons. The main role of the plants is to concentrate carbon from the air. A kilogram of dry cellulose has an enthalpy of combustion of 17.5 MJ [1]. It contains enough carbon to make 0.76 kg (47.6 moles) of methane, once fully hydrogenated. That methane has an enthalpy of combustion of 41.9 MJ [2]. The biomass would supply all of the carbon and a minority of the chemical energy while electrolysis would supply the majority of the hydrogen and the final energy content of the methane.
For land travel all electric vehicles make a TON of sense. However, for airline and oceanic travel, the energy density of a battery simply isn't high enough.
Biofuels may be the only carbon neutral way to accommodate such forms of transport.