The decarbonized doublespeak may not be new but it was jarring coming from the mouth of our new PM, who has an undeniable grasp of the impacts of hydrocarbons but nevertheless talked about “decarbonized barrels” at the press conference following the first ministers’ meeting. And it was particularly painful considering the venue — a province under a state of emergency where more than 15,000 people have fled wildfires.
If there were such a thing as decarbonized oil, it would be hydrogen. Hydrogen is literally what you get if you (magically) remove the carbon from oil. If they mean something else by it, they’re lying.
It is possible to make clean (decarbonized) e fuels. It starts with green H2, and air captured CO2. It is an expensive process even with cheap electricity. Powering oil wells or tar sands with solar doesn’t count.
So… grow plants and then burn plants.
Biofuels/ethanol/SAF are much the same; often derived from corn.
In many cases, the oil/gas/electricity used for harvesting, processing, cracking etc. is actually comparable to or exceeds the carbon released by simply drilling for and burning the oil in the first place.
Solar power per acre will drive a Model Y 200 times further than ethanol will drive at 30mpg. And you can grow crops underneath/around solar. Corn ethanol, and other biofuels, are greenwashing that with fertilizers can emit as much as gasoline.
E-fuels are different. Take that 200 higher energy/range, and making H2 through electrolysis, makes a fuel that can get 100 times the range of ethanol. Can further chemically process that H2 to make gasoline or kerosene, and it is still green if the CO2 input is sourced from the air. H2 is best because it’s the cheapest green fuel, but also because a fuel cell is 2x+ more efficient than an engine. Aviation especially has the most to gain, as H2 is highest energy density by weight fuel, and a typical plane costs 100x more in fuel over its lifetime than its purchase price.
The issue with aviation hydrogen is… well, lots.
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Fuel cells are heavy and direct combustion is inefficient and tougher than burning kerosene.
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Aircraft typically use the wing structural members as the fuel tank walls. Both cryogenic and pressurised options make that a non-starter.
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Lower density means much bigger tanks.
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Self-vapourising fuel is a major crash issue.
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Round trip efficiency for H2 is still terrible.
Plants may not be particularly efficient per km^2 but arable land isn’t actually that hugely scarce.
Reducing aviation is really the only thing that’s actually going to work.
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Same vibes as when they were going on about “clean” coal.