AEP, Alstrom first to store CO2 emissions

The Mountaineer carbon capture and storage (CCS) demonstration project diverts a portion of the plant's exhaust through a device from Alstrom that chills the gas and combines it with an ammonium carbonate solution.

The carbon dioxide is absorbed by the ammonium carbonate solution, creating ammonium bicarbonate, which is then pressurized and heated separately to generate a pure stream of carbon dioxide. That CO2 is then compressed and stored for later injection into geologic formations located 1.5 miles below ground, explains EERE.

Although the project will reveal the feasibility of CCS technology, EERE points out that the treated gas represents only 20 megawatts of output from the 1,300 MW coal plant. AEP has applied for stimulus funding to expand the Alstrom device to handle 235 MW of exhaust from the plant, but even that will represent only 18 percent of the power plant's output, which indicates how far the technology has to go. The larger facility will require the deep geologic injection of about 1.5 million metric tons of CO2 per year.

CCS technology may also be applied to industrial facilities, like refineries and cement plants, notes EERE. To help move the technology ahead, the U.S. Department of Energy (DOE) awarded $21.6 million in funds from the American Recovery and Reinvestment Act in early October to 12 CCS projects.

The projects will demonstrate a variety of carbon capture technologies in applications relevant to power plants, refineries, paper plants, cement plants, and other industrial sources. Many of the projects involve injecting the CO2 into geologic formations. Together, the projects represent a variety of geologic formations in diverse parts of the U.S. DOE plans to invest a total of $1.4 billion in Recovery Act funds to spur progress on CCS technology.