ATTACHED FWIW IS A DISCUSSION BY "ENERGY INSIDER" OF AEP'S CARBON CAPTURE PROJECT IN MASON COUNTY
MAY 15, 2009
Wide-scale deployment is at least five years away. But the architects behind the first-ever power plant to attempt to capture and store carbon dioxide (CO2) emissions will fire up a pilot project in September in a test that could last up to three years.
If the 20-megawatt trial at the Mountaineer Plant in New Haven, W.V., is deemed successful, then American Electric Power (AEP) will implement the same technology in 2011 at another facility in Oklahoma in a 200-megawatt project. After that and around 2015, AEP says that the operations that will use chilled ammonia to scrub the CO2 emissions can be ready for prime time. Those releases would then be compressed and stored permanently underground or be used to help retrieve oil deposits.
Clearly, it's now possible to dramatically cut such pollutants as nitrogen oxide and sulfur dioxide. But it's also becoming increasingly real to trap CO2 in trees or bury it underground. By most accounts, energy usage will rise in the coming decades and coal will remain the primary fuel source to generate electricity. Carbon capture and storage therefore holds the key to future power plant production using fossil fuels.
"We have seen over time that lab initiatives work well in a controlled environment," says Bill Sigmon, vice president of engineering for AEP. "But as you upgrade to commercial scale, it may not work as advertised. We need to go in steps to give surety. If we can get to the 200-megawatt range, then it will give us the surety we need to say that we can count on it."
Power companies contribute 33.3 percent of all CO2 emissions in the United States, according to the Congressional Research Service. Older coal-fired facilities could be retrofitted so as to trap the CO2 before it leaves the smokestack. But such remedies are expensive and less efficient than building modern coal gasification facilities that have the potential to concentrate the CO2, making it easier to capture.
In Wisconsin, WE Energies is piloting a 1.7-megawatt project that is only trying to capture the CO2 using chilled ammonia, which is said by AEP to be more effective than existing options. Others that include "amine" require 30 to 40 percent of a unit's output be diverted for carbon capture. But "ammonia" necessitates just 15 percent.
Powerful Initiative
AEP's endeavor is patterned after that of WE. However, it is different in that it will be the only power plant in operation to both capture and store the CO2. The utility will follow a dual course of retrofitting older plants while also building modern facilities that have the potential to capture carbon emissions. The Mountaineer plant will capture and bury 8,500 feet underground about 200,000 tons of CO2 a year -- a small portion of the roughly 8.7 million tons a year that the plant now emits.
"Our partnership with AEP will result in the world's first clean coal power plant and will be applicable not only for new plants but also for existing power plants," says Philippe Joubert, president of Alstom Power Systems in France, which has developed the chilled ammonia processes now being used by both WE and AEP. Alstom says that its process has demonstrated the potential to detain more than 90 percent of CO2.
It's all part of a clean coal initiative set up under the Bush administration. The program, begun in 2005 and which allocates $2 billion to the cause, provides the means to demonstrate those projects that can capture and bury CO2. The government will provide up to half the money to help commercialize viable technologies. AEP is part of the program but was unable to say just how much of the roughly $100 million price tag associated with the Mountaineer plant that the U.S. government would pay or how much could be passed through to the customers who would benefit from it all.
The key question is not whether the carbon can actually be captured. It can. Rather, it is whether the CO2 can be safely stored underground and whether a given geological disposition will work or have enough capacity for such burial. In AEP's case, it says that the Mountaineer site has been chosen because it is laden with cap rock that will ensure the CO2 stays safely buried 8,500 feet under.
"The technology, along with renewable energy and energy efficiency, has great promise for climate change," says Neeraj Gupta, project manager for the Mountaineer project with Columbus-based Battelle that is working on the sequestration part. "We are trying to figure out if CO2 can be injected in the deep layers and if so, where and at what cost."
AEP's Mountaineer project may be a turning point. The best scenario for it would be if the technology works as advertised and it could be scaled up from 20 megawatts to the next level of 200 megawatts. The worst situation would be that the saline aquifer won't hold the injected CO2 while the chilled ammonia would not perform up to snuff, requiring too much of the unit's energy to trap the carbon.
"We should probably wait and see how the AEP pilot project goes," says Frank O'Donnell, president of Clean Air Watch. "I think if Congress set a carbon cap that declines over time, it will really jump start a lot of projects like this."
AEP's venture could sputter. But it could also succeed and become a harbinger of things to come with respect to carbon capture and sequestration. Today's technologies, however, may not be prevalent down the road. Lots of ideas are being tested that have yet to gain visibility. It's a slow process but one that the coal generators must pursue if they are to remain relevant.
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