"However after the war the technology was "lost", and no one can figure out how they did it."
The technology wasn't lost - it just wasn't economically feasible when oil was at $25 a barrel or less. Germany made it work when oil wasn't available at any price (and with the Russian Army on the march from the east). With oil hovering above $100 a barrel "they" might find that it’s cheaper to use our vast coal reserves and keep the money in the US instead of sending it to the Arabs.
Currently South Africa has a working system and the Chinese have started building their own factories. Link
SECUNDA, South Africa -- Every day, conveyor belts haul about 120,000 metric tons of coal into an industrial complex here two hours east of Johannesburg.
The facility -- resembling a nuclear power plant, with concrete silos looming over nearby potato farms -- superheats the coal to more than 2,000 degrees Fahrenheit. It adds steam and oxygen, cranks up the pressure, and pushes the coal through a series of chemical reactions. Then it spits out something extraordinary: 160,000 barrels of oil a day. For decades, scientists have known how to convert coal into a liquid that can be refined into gasoline or diesel fuel. But everyone thought the process was too expensive to be practical. ===== = One problem is that coal-to-oil projects are extremely expensive. A single plant capable of producing about 80,000 barrels of oil equivalent a day -- less than 0.5 percent of America's daily oil diet -- would cost an estimated $6 billion or more to build. Energy analysts reckon that some coal-to-liquids projects can offer an acceptable return on investment when oil is priced as low as $30 or $35 a barrel, though such ventures might require government tax incentives to reduce operating costs. It seems likely that oil prices will stay above that level for a while, but the longer-term outlook is anyone's guess. An earlier flurry of interest in coal-to-oil facilities in the U.S. during the Carter administration in the late 1970s died after oil prices collapsed.
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