Mountain State Science: Clean Coal Technology

American electric powers, Mountaineer plant in New Haven West Virginia, produces 1,300 megawatts of power every day inside the plant. Coal is pulverized and burned, generating electricity and sending pollutants up into the atmosphere. But with the help of new technology, the plant is experimenting with ways to clean its emissions. In 2009 it unveiled its carbon capture and sequestration or CCS system. Gary Spitz Naugle is a ep's director of new technology development. It'S about two-thirds or 66 % of ATP's fleetest is coal based and when we're looking at the potential for climate legislation, that would require carbon reductions and we're so invested into coal that it's very important that we find a technology that makes coal viable in a carbon-constrained World so so we looked at a lot of technologies and decided that we wanted to to help the development community come up with something that would work at these kind of power plants. The system AEP is testing, uses chillz ammonia to remove carbon dioxide from flue gas. First, the flue gas is piped into the CCS system and chilled so it comes closer to the optimal temperature for the chemical reaction. Then the gas enters a tower and mixes with ammonium carbonate. The ammonium carbonate absorbs the carbon dioxide out of the flue gas and forms ammonium bicarbonate. So at this point the carbon dioxide has been removed from the flue gas, but the technology still has to remove it from the new compound it is formed. This is the regenerator. This is where we take that ammonium bicarbonate solution. We heat it up and we that process of heating it it causes the chemical reaction that happened in the absorber to go in the opposite direction. So tech tricks club website turn it mo diem, bicarbonate back into ammonium carbonate by heating. It up and out of the top of this column then comes a pure stream of co2, and then out of the bottom of this column is the original reagent that we use to absorb co2 is reform, and it goes back to that column to run the reaction. Again, once they've isolated, the carbon dioxide, it's pumped to another area of the plant, here's how they sequester it underground. In an animation provided by a EP, the co2 is compressed into a liquid like state and injected. Under pressure into carefully chosen geologic formations there. It is permanently stored in rock formations, thousands of feet below water tables and drinking water supplies. The targeted storage formations consist of permeable or porous rock, where the injected co2 spreads through the pores in the rock. Much like water fills a sponge. The co2 is effectively trapped from moving upward by layers of very thick and impermeable cap, rock that lies above the porous formations much in the same way, oil and gas deposits have been trapped for millions of years. The CCS system at Mountaineer still isn't anywhere near full-scale right now. It removes about 1.5 percent of the carbon dioxide from the plants and missions, but spits Naugle says the company plans to build a commercial scale system in the future that will remove more of the carbon dioxide. There are different methods of capturing carbon other than the chilled ammonia process. The Mountaineer plant is using, but the process is still so energy intensive. Some argue it negates the environmental benefits of capturing the carbon in the first place. Rory McIlroy is the energy program manager at downstream strategies, an environmental, consulting firm. When you add CCS onto a conventional coal plant with children, moaning a technology, then you're basically losing twenty to thirty percent of your plane's capacity, meaning that you have to use twenty to thirty percent. More electricity just to capture the co2 from the stack and using more electricity to capture carbon dioxide means that the other environmental impacts of coal increase exponentially, which means you're mining, 30 or coal. Processing, 30 % more coal. And you still have the emissions of sulfur dioxide and nitrogen oxides, even if you're catching the co2 using Appalachian example when they mine the coal. You have all the all the related environmental problems to water, to the health of the workers and to the land. If you put CCS on every plant, you're now increasing those impacts per kilowatt hour by 30 %, which is why some scientists are looking to solutions other than CCS. Richard Turton is a professor of chemical engineering at West Virginia University. His work centers on modeling, a different type of power plant, an integrated gasification, combined cycle or IGCC. Basically, IGCC technology turns coal into a gas. The gas is then burned cleaner than regular pulverized coal, plus the excess heat generated, can be cooled to steam and used to generate more electricity. So the combination of running it through a gas turbine and then recovering the heat in a steam turbine is called a combined cycle and it's a relatively efficient way of making electricity relative to just burning coal. If you like, IGCC is a little bit cleaner than regular pulverized coal plants because it's more efficient, so there are fewer emissions per megawatt of energy produced, but it still emits carbon dioxide into the atmosphere. Carbon capture can be used on IGCC plants too, but the problem with IGCC is that it requires a huge capital investment. Curtin says it makes more sense in the long run than a regular coal plant, but that doesn't always matter to investors. It'S like me telling you you know you asked me what recommendation you should buy a car and I say well, the best car in the long run that you can buy is the Mercedes Benz. It'S in a costume. For example, it's gon na cost you eighty five thousand dollars, but in the long run that will be the best for you and you say that's great, but I don't have eighty five thousand dollars. So I'm gon na buy a four word or a toy. You know low a lower end car, so those arguments are fine, but when it comes down to the person who's going to provide the capital investment, that's a much more difficult sale. Even though, in the long run it may make sense. You'Ve still got to come up with that initial amount of money, Rory Mac, immoral, says from an environmental perspective. Igcc is a better technology than carbon capture and sequestration, but he says because current CCS technology is both expensive and energy intensive. It could have the added detriment of contributing to the further decline of Appalachian coal. Appalachian coal is already more expensive than coal from Wyoming's Powder River Basin. Putting CCS on power plants in this region would make our coal less competitive with Powder River Basin coal, because if you are already paying hundreds of millions to billions of dollars to install the technology, that's gon na allow you to keep burning coal. You can't also then burn the highest price coal, because you're gon na that utility would compete itself out of the market, especially with the rise of natural gas. Right now advocates of CCS and IGCC say these technologies aren't the final solution but they're a way to begin. Transitioning away from coal in six hundred years, we're not gon na be using coal. Obviously we're gon na be we're going to either be using nuclear fusion or we're gon na come up with a bio-based technology that will be renewable. The world saw all these problems out. That I'm convinced the medium to the next 30 years, there's no technology that I see coming along, that is going to supplant coal in terms of power generation in this country. Meanwhile, spits Naugle with a EP says using CCS will allow the company to continue operating its existing coal-fired power plant like Mountaineer for the next few decades or until a better energy alternative comes along for West Virginia Public Broadcasting, I'm Erica Peterson in Charleston. You