What the heck is "clean coal"?
What the heck is "clean coal"?
Illuminating answers to environmental questions.
Oct. 7 2008 6:44 AM

What the Heck Is "Clean Coal"?

It depends whom you ask.

In last Thursday's vice-presidential debate, Joe Biden and Sarah Palin seemed to be falling over themselves to demonstrate their support of "clean coal." What is clean coal, anyway, and should I be in favor of it?

Coal plant.
Coal plant

If nothing else, your confusion suggests that whoever came up with the term "clean coal" deserves a raise. After all, the phrase has become so successful that politicians can get in trouble for seeming to oppose it— just ask Sen. Biden —despite the fact that nobody agrees on what it actually means.


It's not hard to see the problems with regular old coal. The mining process destroys the land—not to mention what it does to the miners themselves. In the United States, coal accounts for more than half of nitrogen oxide emissions and about one-quarter of sulfur dioxide pollution, and it's a major source of the particulate matter that makes smoggy air so hard on your lungs. And even among fellow fossil fuels like petroleum, coal is in a class of its own when it comes to emitting greenhouse gases.

Now that we've gotten that out of the way, what's clean coal? That depends a little on whom you ask. The industry-sponsored American Coalition for Clean Coal Electricity defines it as "any technology to reduce pollutants associated with the burning of coal that was not in widespread use" prior to regulations from 1990. By that definition, the group can call any newer coal-based power plant clean. Indeed, as the ACCCE never hesitates to point out, the nation's coal power plants are 70 percent "cleaner" than they were when it comes to regulated pollutants like sulfur dioxide, carbon monoxide, and nitrogen oxide.

The Lantern supposes America's electricity producers deserve credit for those advances—although it's worth noting that many of them came in response to new laws like the Clean Air Act. But that doesn't change the fact that—kilowatt for kilowatt—coal remains just about the most carbon-intensive energy source out there. From the perspective of global warming, at least, the kind of "clean coal" we have now still isn't very clean.

Outside the industry, "clean coal" usually refers to something different: namely, the idea that the carbon dioxide produced from burning coal in power plants might be captured and stored, preventing it from contributing to climate change. There are reasons to be skeptical about this idea. While carbon-capture technology has been demonstrated on a small scale, a larger project in Illinois hit a major snag when increases in its projected cost put its funding into doubt. Indeed, building the infrastructure necessary to transport and store all that carbon presents its own huge challenge. Even supporters within the utilities industry admit that a target of 2020 for large-scale tests of the technology is "very aggressive."

So should you support politicians who support clean coal? It's certainly better than dirty coal—and the United States isn't likely to be rid of either one for the foreseeable future. If nothing else, the greatest benefit might come from exporting carbon-capture technology to other countries that are even more coal reliant than we are. Federally supported research for cleaner energy is a worthy cause, and while it is hard to know the most cost-effective way to spend those dollars, carbon-capture technology seems like a plausible option.

Still, there's no doubt at all that coal—as it's presently burned in power plants, or will be in the near future—is not a clean source of energy. (Even low-emissions coal power would require maintaining those environmentally destructive mining operations.) And that means that the folks who have made "clean coal" into a buzzword are almost certainly using the language of environmentalism to obscure less-noble motives.

Quite simply, a greener use of coal will happen only with a much tougher effort to cut emissions. Even if we had the technology and infrastructure to capture and store carbon dioxide, that process would likely be too expensive for the coal industry to implement at current prices. According to a widely respected MIT study, coal power plants will use that technology only if they are going to suffer financially by emitting so much carbon dioxide.

To their credit, both John McCain and Barack Obama have implied that building new coal plants with existing technology isn't acceptable. (Obama's climate-change proposals are stricter on emissions—and, as a result, more likely to ensure those plants don't get built.) But neither candidate appears too eager to advertise that point in the coal-rich swing states where the election may be decided. At that point, clean coal starts sounding a little more like dirty politics instead.

Is there an environmental quandary that's been keeping you up at night? Send it to ask.the.lantern@gmail.com, and check this space every Tuesday.

Jacob Leibenluft is a writer from Washington, D.C.

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