The same amount of energy from a combustion power plant is produced daily by combining 20 million pounds of coal with 200 million pounds of air, not incidentally yielding an equal weight in ashes and gases.

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Because both of these approaches need totally new plant, they have received less attention than post-combustion capture technologies such as amines, which can be fitted onto the end of existing power stations.

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There is technology in the works today that can economically clean coal before combustion and reduce emissions to levels rivaling the emissions of a natural gas fired plant.

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