One year ago the French company Alstom began a year-long US test of capturing CO2 from the water+carbon-dioxide mix created using their chilled-ammonia technology, in the smokestack of the Pleasant Prairie Power Plant in Wisconsin.
[social_buttons] This week the year’s results were announced. The years average CO2 capture rate was 90%, according to a joint announcement from the EPRI, We Energies and Alstom to the Society of Environmental Journalists.
The 12-month test was just completed after running 24 hours a day on a small sectioned-off portion of the smokestack; working on just 5% of the plants total emissions.
But the test is scalable, and the Electric Power Research Institute, the R&D arm of the utility industry, is optimistic that chilled-ammonia technology will work on a larger scale. It is one of several carbon-capture technologies under consideration as we move to a carbon constrained world.
Next, Alstom will work with AEP in Columbus, Ohio to test a scaled-up version of the technology at the Mountaineer power plant in West Virginia. That test takes the next step as well; not just capturing the carbon dioxide but burying it 8,000 feet beneath the plant site.
Alstom’s chilled ammonia process results in a lower energy cost for capturing CO2 than other techniques under consideration so far. Initial studies currently estimate the average energy penalty at around 20-25% of net boiler output. Alstrom is also working on a technique for capturing carbon dioxide emissions from a gas plant.
The economics is an issue. Even a 20% energy penalty in an industry that is already only 35% efficient in producing kilowatt-hours from coal is costly. Much work is needed, and open minds on all sides of this debate.
Coal power plants comprise about half of the 7,500 carbon dioxide sources that would fall under the Clean Energy Jobs & American Power Act jurisdiction. Cement makers and oil and gas pipelines comprise most of the remainder.