Does seem a good idea. I'm not a chemist and the plausibility of combining carbon from carbon-dioxide from the air with hydrogen split from water hadn't occurred to me but the method does seem obvious when pointed out...
Still, the problem for this would be - Where would all the electricity come from? Green energy probably wouldn't be plausible - I wonder what percentage of the earth's surface would need to be covered with solar panels and/or wind farms to make enough electricity to produce this bio fuel?
Roll on nuclear fusion reactors, and while we're at it, roll on Star Trek style matter replicators! Mind you, if the latter existed I'd probably just replicate V8 petrol engine components and build myself a muscle car then run it on LPG
Simon
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