Blue green algae refined to produce biodiesel has a price tag of around 44 cents a litre. And one can remove any and all water content through, again simple, fractional distillation. To get 200% proof.

A process that boils off the hydrocarbons and leaves the water behind. Some oil wells also have a waterflow content with the oil, which must also be removed.

Well aware of what can happen in flight, if there's water in the fuel. That said, I look forward to electric planes that could fly nonstop Sydney to London.

Driven by solid state star drive motors, where all the energy is applied solely to thrust rather than spinning things, flywheels, props etc. That wastes as much as 85% of the available energy.

New catalyst technology may make water the fuel. Need to harness some of the exhaust heat created, to keep it liquid at altitude.

I prefer to debate folk who see solutions not solvable (know all the reasons it can't be done) problems.

Hydrogen may be another possible alternative if they can get the price down. Methane which is mostly hydrogen is easy to make and cheap. Can be made into liquid methanol via a catalyst.

All the above will have the oil barons spinning for all they're worth to prevent them coming on the market, as viable alternatives.

Have a nice day.
Alan B.

The delusion of green growth and high population could be the biggest mistake humans will ever make.
Taswegian,
Only the educated i.e. Uni-indoctrinated ones. Normal people are fully aware of what's going on but don't get to make decisions on the policies that favour parasitism !