Editor's note: The original online version of this story was previously posted.

Over the next five years at least half a million tons of carbon dioxide will be injected into rock deep underneath the Mountaineer power plant near New Haven, W.Va. Although that is less than 0.00001 percent of global emissions of the greenhouse gas and less than 2 percent of the plant’s own CO₂ output, the sequestration, which began in September, marks the first commercial demonstration of the only available technological fix for the carbon problem of coal-fired power plants, one that many coal facilities around the world hope to emulate.

Coal accounts for roughly 50 percent of the electricity generated in the U.S. and as much as 75 percent of the electricity generated by American Electric Power, says Nick Akins, executive vice president of generation at the utility, which owns Mountaineer. The plant can pump out 1,300 megawatts of electricity, making it one of the single largest coal-fired power plants in the U.S. and a leading source of CO₂ emissions. (The top emitters of global-warming pollution—China and the U.S.—burn nearly four billion tons of the dirty black rock a year.)

As a result, everyone from coal companies to environmental groups have identified carbon capture and storage, or CCS, as critical in enabling significant and rapid cuts in greenhouse gases. But there have been only a handful of demonstrations of the technology to capture the gas and, outside of using CO₂ to pump more oil out of the ground, even fewer attempts to store it.

To capture CO₂ from its smokestacks, Mountaineer will employ so-called chilled ammonia technology, which relies on ammonium carbonate chemistry to pull CO₂ out of the exhaust gases. (The other two basic capture technologies either burn coal in pure oxygen to produce a CO₂-rich emissions stream or siphon off the CO₂ made during the gasification of coal.)

Mountaineer takes the captured CO₂ and compresses it to at least 2,000 pounds per square inch, liquefying it and pumping it about 8,000 feet down into the ground. At that depth, the liquid CO₂ flows through the porous rock formations, adhering to the tiny spaces, slowly spreading out over time and, ultimately, chemically reacting with rock or brine. “We’re not going into a salt cavern; we’re not going into an underground river. We’re going into microscopic holes,” explains geologist Susan Hovorka of the University of Texas at Austin, referring to CCS in general. “Add it up, and it’s a large volume.” In fact, the Department of Energy estimates that the U.S. has the geologic room for 3.9 trillion tons of CO₂ underground, more than enough for the 3.2 billion tons that is emitted every year by large industrial sources.

The two geologic formations below Mountaineer are the Rose Run Sandstone and Copper Ridge Dolomite, which run underneath layers of relatively impermeable rock that will keep the CO₂ trapped. “Part of our project is to kind of take those through their paces and get an idea of their acceptance of CO₂,” says Gary Spitznogle, a CCS engineering manager at American Electric Power. After all, a similar effort in Ohio revealed that formations there stored less CO₂ than expected. The company will monitor the CO₂ via three specially drilled wells, in addition to the two wells for pumping the CO₂ down in the first place.

The process of capturing and storing carbon dioxide may be simple chemistry and geology, but it has significant industrial costs. American Electric Power alone will pay $73 million for just the capture technology at Mountaineer and has asked for $334 million in federal stimulus—half the total cost, the company says—to scale up the project to nab roughly 20 percent of the plant’s emissions in future years.

2 Comments

1. 1. dwbd 08:24 PM 11/1/09

   The Canadian Gov't are planning to spend $2 billion on a dubious scheme to capture & sequester 5 million tonnes of CO2, at a cost of $400 per tonne. That way the Oil Gang gets to abuse public land to sell Oil at a profit, gets to sell the NG to process the Oil at a good profit, and gets the taxpayer to pay for a $2 billion public relations exercise – to pretend they’re seriously going to cut CO2 emissions!
   
   One example of a nuclear alternative, the Hyperion Nuclear Reactor. With 70 MW thermal output, well suited for providing process heat in the Tar Sands. Cost C$32 million. See:
   
   http://nextbigfuture.com/2009/10/hyperion-power-generation-uranium.html
   
   With a zero CO2 output, it will produce 6.2 TWh of heat within 10 years, before needing refueling. Displacing NG, that will amount to 1.2 million MTs of CO2 avoided. Displacing Coal Thermal energy, that will amount to 1.8 million MTs of CO2 avoided.
   
   Cost of NG CO2 avoided = C$32 million / 1.2 million MTs = $27 per MT.
   Cost of Coal CO2 avoided = $17 per MT.
   
   Compare with the Alberta Gov’t CCS special of $400 per MT.
   
   That’s just using one fuel cycle. What about including two or three fuel cycles? Probably drops below $10 per MT.
   
   But there’s more to consider. We are also avoiding the cost of the Natural Gas or Coal fuel over the 10 year Hyperion fuel cycle.
   
   Taking NG @ a forecast price of $7 per GJ, and using a 5%, 10 year bond to finance the NG purchases, that yields a Present Value of $121 million, fuel cost.
   
   Taking Coal @ a delivered price of $50 per ton, that would be $43 million fuel cost.
   
   Conclusion. Each Hyperion Nuclear reactor used instead of CCS, would save $480 million in CCS costs, and $121-$32 million = $89 million in NG fuel costs, or $12 million in Coal fuel costs. IN OTHER WORDS ZERO CARBON IS NOT ONLY A FREE BONUS, BUT A MONEYSAVER!! AND THAT’S JUST FOR ONE FUEL CYCLE!!
   

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2. 2. dwbd 08:34 PM 11/1/09

   Another point about CCS. The Fossil Fuel companies are getting total indemnity protection from the Government for any releases of their supposedly contained CO2, that could suffocate every living thing for miles around. So much for Price-Anderson protection for Nuclear. This rarely mentioned fact makes Price-Anderson look like a hand slap.

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