"Clean coal is an umbrella term and public relations term used to promote the use of coal as an energy source by emphasizing methods being developed to reduce its environmental impact. These efforts include chemically washing minerals and impurities from the coal, gasification (see also IGCC), treating the flue gases with steam to remove sulfur dioxide, and carbon capture and storage technologies to capture the carbon dioxide from the flue gas. These methods and the technology used are described as clean coal technology. Major politicians and the coal industry use the term "clean coal" to describe technologies designed to enhance both the efficiency and the environmental acceptability of coal extraction, preparation and use,[1] with no specific quantitative limits on any emissions, particularly carbon dioxide. There are, however, zero coal-burning power plants in the United States that utilize any form of clean coal technology.[2]
It has been estimated that commercial-scale clean coal power stations (coal-burning power stations with carbon capture and sequestration) cannot be commercially viable and widely adopted before 2020 or 2025.[3][dead link] This time frame is of concern to environmentalists because, according to the Stern report, there is an urgent need to mitigate greenhouse gas emissions and climate change.
The concept of clean coal is touted as an environmentally acceptable solution to climate change and global warming by coal industry groups. Greenpeace is a major opponent of the concept because emissions and wastes are not avoided, but are transferred from one waste stream to another."