Excerpt:
But there aren't really any other options for processes like this. Making synthetic liquid hydrocarbon fuels always consumes a lot more energy than you could get by burning the fuel, so it's mostly witless to make them using fossil power. (The US military is interested in making jet fuel using coal, but this is merely because America has a lot of coal mines and potentially not enough oil wells. The Germans who developed such processes originally did so for similar reasons.)
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