The dividend yield of Arch Coal Inc stocks is 3.42%.

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Shell's gasification technique consists of partially combusting pulverized coal to yield carbon monoxide and hydrogen gas, which combine to form synthetic natural gas.

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There is the further issue of the quality of coal, since the majority of the world reserve is of lower thermal quality than the top-grade anthracitic coal, and will yield less energy per tonne either burned directly or in the form of syngas in ICGC plants.

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For their calculations, the two assumed that where there was a gap between demand and conventional supply it would be filled with synthetic fuels, first with tar-sands oil and later with oil from coal and shale. (According to high-end estimates, coal and oil shale could together yield some ten trillion barrels of unconventional crude.) They then calculated what the impact would be on global carbon-dioxide levels.

NEWYORKER: Unconventional Crude