Clean coal
| Clean coal | |
|---|---|
| MISLEADING | |
| "Modern "clean coal" technology allows coal to be burned for electricity with little pollution and, through carbon capture, without significant climate impact." | |
| Domain | Science & Environment |
| Tactic | Propaganda Technique False Context |
| Era | Current |
| First seen | 2000s |
| Origin | Coal industry marketing, especially a multimillion-dollar advertising campaign by the American Coalition for Clean Coal Electricity beginning in 2008 |
| Last reviewed | 2026-10-27 |
| Further reading: books on Science & Environment | |
The phrase "clean coal" has been used by the coal industry and its political supporters to describe coal as a modern, environmentally responsible energy source. It refers to two different things: technologies that reduce conventional air pollutants from coal plants, and carbon capture and storage (CCS), which aims to prevent carbon dioxide from reaching the atmosphere. Pollution controls have greatly reduced some emissions, but coal remains the most carbon-intensive major source of electricity. Large-scale carbon capture at coal plants has proved expensive, technically difficult and rare; several flagship projects have failed, been scaled back or underperformed. As a description of the coal power that actually exists, "clean coal" is misleading.
The claim
"Clean coal" campaigns present coal as cheap, reliable, domestic and increasingly clean, implying that new technology has solved coal's environmental problems. In 2008 the American Coalition for Clean Coal Electricity, an industry group, spent tens of millions of dollars on advertising, including during presidential debates. Politicians of both major US parties have used the phrase.
Origin
Coal plants have long been major sources of sulfur dioxide, which causes acid rain, nitrogen oxides, particulate matter, mercury and carbon dioxide. Regulations such as the US Clean Air Act amendments of 1990 led plants to install scrubbers and other controls that cut sulfur dioxide and particulates substantially. As concern about climate change grew in the 2000s, the industry adopted "clean coal" to cover both these improvements and the promise of carbon capture.
What the evidence shows
- Carbon intensity. Burning coal emits roughly twice as much carbon dioxide per unit of electricity as burning natural gas, and far more than nuclear, wind, solar or hydropower over their life cycles. Pollution controls for sulfur, nitrogen and particulates do not reduce carbon dioxide emissions.
- Carbon capture at scale is rare. Very few coal plants in the world capture carbon. The Kemper County project in Mississippi, intended to gasify coal and capture carbon, saw costs rise from about $2.4 billion to more than $7 billion; in 2017 its owner abandoned the coal gasification portion, and the plant runs on natural gas. The Petra Nova project in Texas captured carbon from part of one unit's emissions and used it to pump more oil from an oil field; it was shut down in 2020 when oil prices fell, before being restarted under new ownership. The Boundary Dam project in Saskatchewan has repeatedly captured less carbon dioxide than its design target.
- Partial capture. Even successful projects typically capture carbon from only a portion of a plant's output, and capturing carbon consumes a significant share of the plant's energy.
- Other impacts. Coal mining causes landscape destruction, water pollution and miners' health problems, and coal ash, the residue left after burning, has caused major spills, such as the 2008 disaster at Kingston, Tennessee.
Carbon capture technology may play a role in reducing emissions, especially from industrial processes such as cement production. But it has not made coal power clean.
Why it persists
"Clean coal" is a powerful slogan because it addresses public concern about pollution and climate without requiring change. It appeals to coal-producing regions where jobs depend on the industry, and it lets politicians support coal while appearing environmentally responsible. The phrase blends real achievements, such as reductions in some pollutants, with unrealized promises.
Lessons for readers
- Ask which pollutants a "clean" technology actually reduces.
- Distinguish between technologies that exist at scale and those that are promised or experimental.
- Look at actual project outcomes, including costs and performance, not just announcements.
- Be cautious of slogans that combine two different claims under one label.
- Compare emissions across energy sources on a life-cycle basis.
See also
- Climate science is too uncertain to act on
- Exxon did not know fossil fuels would cause global warming
- Acid rain was an exaggerated threat
- Merchants of Doubt (Oreskes and Conway)
Sources
- US Energy Information Administration, carbon dioxide emissions coefficients by fuel.
- Ian Urbina, "Piles of Dirty Secrets Behind a Model 'Clean Coal' Project," The New York Times, July 5, 2016.
- Intergovernmental Panel on Climate Change, Climate Change 2022: Mitigation of Climate Change (2022), chapter on energy systems.
- Institute for Energy Economics and Financial Analysis, analyses of the Boundary Dam and Petra Nova carbon capture projects.