Gallery: IS IT GREEN? Clean Coal


Throughout this past election season we heard both major-party candidates give a lot of love to “clean coal.” The phrase sounds great to Americans concerned about our dependence on foreign oil, and the U.S. has enough coal to generate our electricity for hundreds of years – if it’s “clean”, why not? But what do “clean coal” technologies really entail, and can an ancient energy source responsible for 40% of U.S. CO2 emissions really clean up its act?

Anyone concerned about the effects of human activity on the environment should be immediately skeptical of the phrase “clean coal.” The first clue should have been the usage of the term by the American Coalition for Clean Coal Electricity, an advocacy group for coal mining and utility companies. The exact meaning of “clean” in “clean coal technology” is slippery, but ACCCE’s web site defines it this way:

Clean coal technology: Any technology to reduce pollutants associated with the burning of coal that was not in widespread use prior to the Clean Air Act Amendments of 1990.

So “clean” really means “cleaner.” It refers to any techniques that improve on practices that were less regulated before 1990.

The Clean Air Act of 1990

Coal-fired plants are currently responsible for about 40% of the U.S.’s CO2 output, and they produce sulfur dioxide and nitrogen oxide, mercury, carbon dioxide, and fine particulates commonly called “soot.”

Sulfur dioxide and NOx are the causes of acid rain. The 1990 amendments required plants to reduce sulfur dioxide emissions by 50% of the levels emitted in 1980, and gave them 10 years to do so. The amendments also established a commission that created regulations in 1994 to reduce NOx emissions by 55 to 65% of 1990 levels.

Mercury is a toxin that bioaccumulates as it moves up the food chain. Humans can be affected by eating contaminated fish and shellfish. Mercury affects fetal development. The 1990 amendments called for more research, and emissions regulations were not finalized until December of 2004.

Particle pollution, or soot, can cause respiratory and heart problems when inhaled by humans. The 1990 amendments called for a 95% reduction in particulate pollution by coal-fired plants.

The 1990 amendments ignored the issue of carbon dioxide. As a result of a ruling by the Bush Administration, carbon dioxide is not currently classified as a dangerous pollutant and can’t be regulated by the Clean Air Act.

Can Coal Clean up Its Act?

Based on this summary of the 1990 amendments, we get some idea of the state of coal cleanliness in 1990. The amendments were very concerned about soot, which is visibly dirty and obviously harmful, but they were not interested in carbon dioxide emissions. The amendments were moderately concerned about acid rain, and slow-moving with regard to mercury. So it follows that coal-fired plants have since implemented technology that regulated pollutants with rigor corresponding to the level of national concern reflected in the amendments.

The ACCCE praises any technology that reduces pollutants that was not in widespread use before 1990 as “clean” – low standard. However It is possible to reduce most of the dangerous emissions from coal-fired plants to near-zero levels.

The smoke can be pumped through a “baghouse,” which captures the particulates in mesh bags. The smoke can be run through a spray of water which combines with the sulfur to form sulfuric acid, which then falls into the “scrubber” without entering the atmosphere. Activated charcoal particles can be ground up and sprayed into the baghouse, where the mercury will get caught on the particles and be trapped in the mesh.

The hardest part is reducing CO2 emissions. There is research into methods for isolating the CO2 and sequestering it. A popular idea is carbon capture, which involves injecting the CO2 under rock formations that would keep it trapped indefinitely in the earth. MIT estimates this technology won’t be possible on a commercial scale until 2030. It would also be costly and the consequences of sequestering the gas underground alarms some environmentalists.

Another idea is integrated gasification, which involves pulverizing the coal and heating it until it becomes a gas. But gasification plants have issues with reliability and require more maintenance. Environmentalists say it results in contaminated wastewater and that it’s too expensive to be practical.

Is it clean?

With vigilance and commitment, yes.

But is it green?

No. The goal of successfully reducing carbon dioxide emissions is undermined by the absence of full support and high costs. The highest cost is time. Rather than waiting for the technology to become available and then waiting longer for it to be phased in, we should pursue alternative sources of energy that are less hostile to the environment. Implementing wind and solar power on a wide basis is preferable to jumping through hoops to accommodate the nasty byproducts of an antiquated electricity source just because it’s cheap.

+ American Coalition for Clean Coal Electricity

+ U.S. Clean Air Act


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  3. trued June 9, 2009 at 7:49 pm

    I am eager to know who the experts on coal are who you interviewed – the pro and anti. As soon as I identified the GE logo at the bottom of the page, I was unable to take any of the article’s contents seriously. GE has launched a huge pro clean coal ad campaign that wreaks of green scamming.

  4. PeterSon_12k December 24, 2008 at 1:40 am

    There is no such thing as clean coal today, and other solutions like efficiency and renewables need to be implemented to slow global warming. We scrutinize the presidential candidates during the debate process, and we should make sure to scrutinize the ulterior motives behind the so-called “clean coal” ads as well.

    In the ads, happy families and intelligent scientists inform us that clean coal technology is out there, and we needn’t worry about losing the wonderful energy source that is coal just because it has a bad track record of being a health risk and contributing to global warming.

    Follow the

  5. frflyer November 15, 2008 at 2:26 pm

    A few more thoughts. Further proof that we are being misled and disninformed. I would bet that 90% of Americans have not even heard of solar thermal power, other than in the form of passive solar, water heating etc. How are we supposed to make good judgements when the most promising source of power we have isn’t even something most people are aware of?
    Using 1% of our southwest desert areas for solar thermal power plants would power the whole country. Again, that’s less land than now used for coal mining. And the environmental impact on the land is far far less.

    1% of the Sahara desert would power the whole world.
    3% of Morocco would power all of Europe.
    Solar thermal is already competitive at peak demand rates in sunny areas like California. Solar thermal plants can store heat to produce power at night and when clouds pass over. Storing energy as heat is at least 20 times more efficient than storing electricity. The heat can be stored in molten salt, water or oils. Solar thermal technology is so low tech that we could have done it 100 years ago. It doesn’t require any exotic materials, or anything more high tech than a steam electric generator.

    Be sure to read the article at salon dot com mentioned in my previoius post.

  6. Jules November 10, 2008 at 8:49 pm
  7. Adrianne Jeffries November 10, 2008 at 6:33 pm

    1. This article was not a comprehensive overview of coal. I wanted to make the point that while technology exists to make coal “clean,” i.e., control pollutants, it’s not “green” because of the issue of carbon dioxide emissions. I did leave out both the environmental effects of strip mining coal and I did not discuss different grades of coal.

    2. The technology used in IGCC plants is newer. We’ve been burning coal for hundreds of years, so that technology is more reliable at the moment. That’s not to say that the operating reliability for IGCC plants won’t improve and eventually equal that of current coal-burning plants. Utility companies that would be the ones to venture into building IGCC plants are hesitant because their research shows that the plants have reliability issues — for example, the Canadian utility company EPCOR says this on their web site: “Demonstration plants built in other countries have experienced high capital and operating costs (at least 1/3 higher) and issues with operating reliability. ”

    If anyone knows of any studies that contradict the idea that IGCC plants have a lower operating reliability than coal-fired plants, I would be interested to see them.

    3. Instead of attempting to confirm or deny whether it contaminates wastewater, I prefaced it with “environmentalists say.”

  8. Jackseppelin November 10, 2008 at 5:35 pm

    No, clean coal is not an environmentally progressive idea. It is not even really clean. It is not energy efficient. It is not green technology.

    But we have lots of coal in the world. We have lots of coal in the United States. We have a few places in the US that could greatly benefit from a clean coal initiative. It is a socially progressive plan to develop this technology for possible export (including American technology sales to developing nations) and creation of jobs.

    Of course, once we have our liquid coal, it burns well enough. We do it because coal in plentiful enough. Is is something greenies should be getting behind? Yes, once they realize that some concessions can be made for the good of their fellow man. The earth will heal. And it certainly will be here longer than we will.

    That said, stay the hell out of ANWR. Alaska is one of the remaining environmental treasures of the earth. Do not drill there. There are many other places that we can drill. Do no drill off American coasts, though good luck trying. heh heh. I don\’t understand any progress has been made using wave turbine technology but the news Navy contract might make some difference. Just watch the plankton, algae, and plastic soup levels in the oceans. All of this temperature weirding has much to do with the oceans.

    Solar and Hydro are the way to go.

  9. Jules November 10, 2008 at 2:50 pm

    You make no distinction between the types of coal being used.
    I don’t think you ‘ve ever been to a coal-fired power plantt and seen firsthand the technologies already in place as well as new technologies that are being developed. Nothing like going and talking to the people actually using coal to really learn what’s going on.

    “But gasification plants have issues with reliability and require more maintenance.
    What independent engineering firm corraborates this assertion? Or is this just your opinion, and if so, based on what?

    Environmentalists say it results in contaminated wastewater and that it’s too expensive to be practical.”
    Again, what unbiased engineering or scientific study group support this claim?

    These are but several examples of your bias and misinformation that permeates your article.

  10. Adrianne Jeffries November 10, 2008 at 7:57 am

    @Jules: Please point out any misinformation you see in the post. I wrote this article after a week of research and two expert interviews, one pro-coal and one anti-coal. My editors and I are not looking to publish errors of fact. Comments are a great way to fact-check posts, especially since Inhabitat readers tend to be informed citizens, and we welcome scrutiny.

  11. Jules November 9, 2008 at 9:33 pm

    What a mishmash of misinformation and bias. Coal is our future for powering electrical generation for a long time to come. The old photos, as well as the stance of the author that, no matter what I’m shown in the way of evidence, I’m still against it. Typical knne-jerk liberalism. I live in Wyoming ,and am aware of the efforts being made to constantly improve the process of burning coal with less emissions and more efficiency. This is really funny that GM sponsored the link to this story. The mind boggles at the amount of coal burnt on their behalf to produce the electricity they’ve needed to produce their ‘wares’ for even the last fifty years, What bunk-

  12. Ty November 9, 2008 at 4:37 pm

    Would clean coal be an oxy moron?

  13. Jamino November 9, 2008 at 3:41 pm

    While it is true that there is no such thing as clean coal, cleaner coal is very important. If the US had agreed to the Kyoto protocol earlier then much headway would already have been made into converting existing power stations. All of which can be retrofitted with the scrubber technology.

    Strangely enough it isn’t branded “clean coal” in the UK but i think that’s just the way the US works. The simple fact is that the shear amount of time invested in developing the new technologies to make renewables viable means that there has to be some power source in the developmental phase. Clean coal is not the solution, it’s a stop gap measure until there comes a time when we have a viable renewable option, or hopefully at some time in the future fusion, but that’s a hell of a way off. In my opinion nuclear power is the true way forward for now, but that carries it’s own problems.

    The idea is that renewables are slowly able to take over our energy production needs, but the point is it’s a slow process. A new off shore wind far was just opened in the UK, making the UK the largest producer of off-shore wind power in the world. The problem is it only produces enough power for 300,000 homes. A drop in the ocean, but I guess a step in the right direction.

  14. antiapathy November 8, 2008 at 9:12 pm

    No, coal is not clean. The author presents a great case that burning coal cannot be accomplished cleanly. What\’s left unmentioned is that getting the coal out of the ground is even worse. Trees and soil are stripped off of mountain tops, then coal is processed with horrible chemicals like arsenic. Plus there is a major underground mining disaster every year or so that ends up killing dozens of exploited workers. Those not killed in a mine collapse will try to dodge cancer after working with carcinogenic materials for a lifetime.

    People who think there are not enough resources to get America off of fossil fuels are victims of a massive disinformation campaign by the coal, oil, and gas industries. If we put our resources into researching alternative energy sources we could accomplish it. We can drill miles underground for oil, why can\’t we drill more geothermal power plants? We have offshore oil platforms, why not offshore wind farms? And as always, why is conservation not on the forefront?

  15. kellermfk November 8, 2008 at 1:12 pm

    It is simply not possible to replace all coal energy with wind and solar energy – do the math.
    A middle-of-the-road approach that relies on a wise blend of conservation, renewable, natural gas, nuclear and “cleaner” coal is more realistic and significantly more cost effective.

  16. Avarana November 7, 2008 at 5:06 pm

    the front page says “there is actually no coal in E-Coal”. So, it’s not coal.

  17. jeanX November 7, 2008 at 4:54 pm

    You leave out all the people have died while mining coal.
    It’s a dirty job, but it should not require a single life.
    Let’s be attentive to them and find some other job.

  18. TRM13 November 7, 2008 at 3:49 pm

    Yes clean coal does exist. E-Coal from satisfies the most stringent deffenition of the work clean and can be used in existing plants without modification.

  19. pritchet1 November 7, 2008 at 10:04 am

    I added this link to our “Clean Coal” page at PESWiki – Skeptical/Downside section –

    (Nicely done, by the way Adrianne!)

  20. yellow eyes November 7, 2008 at 10:01 am

    “Clean Coal” is an oxymoron. Coal companies are the modern snake oil salesmen.

  21. Goodmachine November 7, 2008 at 5:14 am

    “clean coal” that’s a funny term like “civil war”

  22. Steve N. Lee November 7, 2008 at 2:48 am

    I completely agree with your conclusion, Adrianne – we should strive to create new technologies and embrace those green sources we already have.

    There is no such thing as ‘clean coal’, only coal that takes vast amounts of resources to make it less polluting. For example, how much water will be needed for all the cleansing processes mentioned above? Water is one of our most valuable resources (if not THE most valuable – without it we’ll die!) and yet we take it for granted and waste almost as much as we use.

    Some nations languish in poverty, primarily because they don’t have water to grow crops to sustain themsevles and energise their economy, and yet we in the privileged West treat water with utter disdain, not realising that it too is a finite resource and that if we don’t safeguard it for the future, our economies could grind to a halt and our bellies become distended for want of food.

    But there is hope on the horizon. I wrote an article recently which listed the top environmental achievements of 2008 and was amazed while researching it to discover just how much we are embracing alternative energy. Wind farms, solar energy, solar thermal, geo-thermal, wave power… projects are springing up all over the world. It’s these initiatives we need to embrace and expand upon as it’s only these that are truly going to make a difference and safeguard our future. Anything else is simply foolishness and naivety.

    Steve N. Lee
    author of eco-blog
    and suspense thriller ‘What if…?’

  23. Scott November 6, 2008 at 8:35 pm

    Thanks for all of that information and I couldn’t agree more with the conclusion!

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