How cleanly can they burn coal and how likely is a given coal plant in the US to be using such technology now and in the future?
Someone I know believes that eventually the US will turn more and more to coal as an energy source, tapping into the vast reserves that this country has. He says it won’t be an environmental disaster because we can burn coal very cleanly now. I find his assessment overly optimistic even when putting the effects of mining aside. Am I wrong?
Very cleanly, and for the most part any operating plant is using modern clean technology already.
Una Persson should be by shortly with the facts and figures I don’t have at my disposal substantiating this.
It’s already much the largest contributer to electrical power generation. This site states:
Note that oil is a small part of the total.
He’s dead wrong.
Most of New England is experiencing severe problems with acid rain. The acid is caused by the massive coal plants in the middle of the country. Prevailing winds push the various by products of combustion to the Northeast where they mix with water vapor and fall as acid rain. In the last 20 to 30 years building facades and stone monuments that have been in place for 100 to 200 years have been virtually eaten away by the rain.
I don’t pretend to understand why the Bush regime wants to ignore it but the various state governments in the Northeast have filed suit against the EPA for failing to enforce standards that were adopted 20 to 30 years ago.
There are different kinds of clean, too.
For decades, emissions of sulfur and nitrogen oxides have caused acid rain, and various means have been adopted to remediate these. I think this can be done very well, but whether it is is driven by law.
Now, awareness of greenhouse gasses and global warming have created new issues. This is really pretty awful for coal, because in a sense the whole point of burning coal is to get the energy that comes out when you make CO2, so it seems like any method that gets rid of the CO2 can’t harvest the energy. There are ways of sequestering it, and I guess other approaches. There was a good and detailed article about this within the last year or so in, I think, Scientific American - or it may have been The Economist.
Interestingly, now that we are worried about CO2, I have started seeing coal industry advertisements that look to me like they are trying to mislead the public into confusing acid rain remediation, which is pretty accessible, for CO2 remediation, which is less so.
Older coal technologiues are not very clean at all, although there are certain kinds of technologies that can be retrofit to these plants to clean them up considerably (scrubbers and such). However, what most folks are talking about when they want coal to be part of our energy future ios clean coal technology, which is a way to gasify the coal first and then burn it. Any emissions can be sequestered and stored underground. This is not a pie-in-the-sky technology or method but it is very new and so has not been adopted much yet.
Right - this is what happens when you burn anything. When you burn fossil fuels (coal, oil, natural gas) you release carbon that has been underground for a long time.
This is very, very wrong. A loophole in the Clean Air Act allows the grandfathering of existing coal plants. This frequently means that power companies find it far cheaper to operate the old style, soot spewing plants than to build new ones. Couple the cost of the retrofit with legislative unwillingness to build any new coal plants and instead just make useless, but politically popular noise about “renewable” energy, and you have the continued use of dirty coal. A third factor would be that many utility regulations specify that the energy must be generated the cheapest way possible.
Here’s an article that touches on the subject og the gassification issue: Dirty Secret: Coal Plants Could Be Much Cleaner
>Right - this is what happens when you burn anything. When you burn fossil fuels (coal, oil, natural gas) you release carbon that has been underground for a long time.
Well, it’s more subtle than that. Natural gas has lots of hydrogen, so much of the energy comes from creating H2O. Coal has much less hydrogen, much less of everything besides carbon. If there were some way of burning all of a fuel except whatever will create CO2, gas would still produce lots of energy (though much less than before), but coal would hardly be worth fooling with.
Just wait until I can cite Big Coal… by Jeff Goddell (IIRC). I set it aside a few months ago after getting royally depressed by how horrible the industry is, from mining to transport (the railroad companies are the real baddies in the whole equation) to burning.
Hmm. Thanks for the answers but there seems to be some contradiction among them. Can anyone else weigh in?
The bottom line is this: It’s possible to create a coal-burning plant that is “relatively” clean from pollutants - excluding CO2. Most Coal-fired plants are still heavy polluters though, because of the expense. AFAIK, no one has demonstrated a CO2 sequestering system that is shown to work economically on a production scale.
So, if you consider CO2 to be a pollutant, than coal is one of the worst possible choices for a fuel.
I did a postdoc at the EPA working on some flue gas cleaning technologies and I would second this. You can with existing technology eliminate 99% of the SO2, NOx, and Hg coming out of the stack fairly easily, but it comes at a price. Technologies do exist for capturing CO2 do exist but they are even more pricey (especially since there is so much of it to capture) and sequestration is still a bit of a question mark. Coal gasification would make the capture part easier but that wouldn’t help with all the current combusters.
Depends on what you mean by “clean.” As Baracus points out, there are adequate technologies out there that can remove almost all of the SO2, NOx, and particulate matter from coal combustion exhaust. The folks who posted that coal is not clean are right in that there are many plants that do not have these technologies, and under the existing Clean Air Act, do not have to install them. Recent regulations are beginning to force more and more plants to install these technologies, but it will be a while before they all have to (if ever).
When it comes to CO2, there’s really nothing out there yet that can remove it from coal flue gases. And then there is the “minor” detail of what to do with all that CO2 once it’s been removed. Gasification is seen as one approach to removing all the pollutants, but that’s been “almost ready” for quite a while. So far, though, the economics still favor the traditional pulverized coal boiler/turbine/generator approach.
There are also a wide range of trace elements that are present in coal in relatively high levels - mercury, nickel, selenium to name a few. It’s also got quite a bit of iron in it, which is starting to come under scrutiny as a factor in health effects associated with exposure to particulate matter.
My view is that coal is pretty much the dirtiest fuel around, but there is so much of it that we’ll end up having to use it, with all the emission controls and carbon capture technologies installed. It just won’t be nearly as cheap as it used to be.
Currently, the Department of Energy is working on the FutureGen project to create a coal-based, zero-emission, power plant. The plant will employ coal gasification technology while capturing and sequestering carbon dioxide emissions. Of course, it’s just a demonstration project (and an expensive one) at this point.
Really? And your expertise to make an authoritative statement like that is what, exactly?
Really? Just the coal plants? None of it comes from industrial sources, CARS, and other things? And none comes from those coal plants in New England itself? Hello, Brayton Point? Yoo hoo, Brandon Shores? Are you there, Crane? Portland, don’t be shy! Really, I can list a couple score or so if have to.
Given that my clients are the recipients of enormous fines and are spending tens of millions of dollars to meet SO2 and NOx regulations, I’ll bet they wish that the Bush “regime” was ignoring them. Oddly, somehow, in the real world utility companies are meeting CAA Acid Rain emissions standards.
Sure, Congress grandfathered in hundreds of coal plants and they have a very long schedule to reduce emissions. You might want to ask the “Democratic regime” why they don’t simply close the gap by requiring BACT on all coal plants in the US. It would be very simple to do - just pass a bill. Even if they couldn’t get a veto-proof majority, they could try. But I notice you conveniently ignored that because you wanted to join in the age-old “slip in an anti-Bush rant in GQ” thing.
OK, what’s your expertise in this field?
Do you know why the “loophole” was created? The “loophole” was created for three reasons. First, scrubber technology at the time the CAA amendments were passed SUCKED. Scrubbers had very high unavailability, the technology was still up in the air (and even today has some uncertainty, if you watch the battle between wet, semi-dry, and dry scrubbing technologies; SCR versus SNCR versus hybrid SCR/SNCR, etc.). Second, do you have any concept of how much engineering and materials are required to make a large scrubber, and how much it would cost? There simply was not and still is not the manufacturing and engineering capability to add scrubbers to ALL coal plants in the US in any short timeframe. Even right now my friends at B&W tell me they’re walking away from HUNDREDS of millions of dollars in environmental projects because they don’t have the staff to work on them. As is my company -we walked from more that a quarter billion in work over the last 18 months, because there either were no staff, no parts in the near future, or no ability to get contractors. And we’re only in a minor crunch time now - you can get it done, if you have the money and patience, but it’s not easy. Finally, with respect to fuel switching, when the CAA amendments were passed there was neither the low-sulfur coal mining capacity nor the transportation infrastructure available to supply ALL coal plants with low-sulfur coal. Guess what - there still isn’t, even though Wyoming and Montana have seen low-sulfur coal mining expansions of enormous scales.
Could things have been pushed anyhow? Could implementation have been faster? Sure it could have, but the scales involved are huge. Putting a full SCR+FGD on 800+ coal plants is something that would have been an economy-changing impact along the lines of a war. One of my clients is looking at putting on 3 FGD plants and 3 SCR systems for a total of just under $1B when all’s said and done. That’s the cost for just 3 of them (including needed retrofits of plant equipment, all those things that non-Engineers never consider, such as new fans, new ductwork, ammonia storage, limestone receipt, gypsum production plants, etc.
You are correct to a large extent, but in some cases logistics of low-sulfur coal delivery are the fault of homeowners, land owners, and towns who line up to file nuisance lawsuits and do everything that they can to block new rail lines to get cleaner coal through the US. And the Mississippi River is a huge choke-point, too.
None of which challenges or disputes what A Monkey With a Gun says. Somehow I am guessing if that these systems resulted in a massive savings of money instead of environmental savings that companies would find a way to get them up and running.
In terms of applied technology, that is, what EPC folks are saying: our experience is with new coal plants, we guarantee about 95%-98% SO2 removal (depending upon the technology used), 95% NOx removal, and 90% mercury (some claim 95% or more; I say show me the money) removal. With a fabric filter baghouse, or better yet an ESP + polishing baghouse when used with ACI, we can guarantee greater than 99.95% flyash particulate removal.
CO2 removal sadly is a joke on anything but a pilot scale right now. What’s the largest continuous CO2 removal plant right now, about 5MW? Or is the 30MW one online? I’m sure the folks at places like Jeffrey, Monroe, Drax, and Taichung will be pleased to know that about 1/80 to 1/150 of their CO2 can be captured. So yes, to answer the OP, unless you count CO2 as a “pollutant” you can get a coal plant to be pretty damn clean. FTR, I’ve posted about this over the past 7 years, and may have much more detailed past threads on this subject.