Carbon Capture & Storage
Despite significant efforts, carbon-capture and storage (CCS) has yet to be demonstrated on a large scale as many technical, financial and legal questions remain unanswered. Though innovative carbon-capture research is still under way worldwide, no leading new technology has emerged. We believe the industry needs to focus on technologies with the greatest promise so that available dollars can fund significant advances in fewer technologies, rather than small advances in a large number of technologies.
AEP and CCS Technology Development
AEP has participated in three projects to help advance carbon-capture and storage technology, all of which were conducted at its Mountaineer Plant in New Haven, West Virginia. The projects include:
- Geologic characterization studies, 2002 – 2004
- Technology validation, 2007 – 2011
- Commercial scale front-end engineering and design (FEED), 2010-2012
Between September 2009 and May 2011, AEP operated the first fully-integrated CCS project at an existing coal-fueled power plant. AEP built and operated a 20-megawatt CCS facility that successfully captured and stored carbon dioxide from the company’s Mountaineer Plant. The first of its kind in the world, AEP’s technology validation project:
- Operated more than 6,500 hours
- Captured more than 50,000 metric tons of CO2
- Stored more than 37,000 metric tons of CO2
In May 2011, AEP achieved the objectives that we expected to achieve from the validation scale CCS installation and discontinued operation of the facility. AEP continues to participate in other projects and initiatives.
About the Technologies
CO2 capture – The Mountaineer Plant CCS validation used Alstom’s patented chilled ammonia process for post-combustion CO2 capture. The process used ammonium carbonate to absorb CO2 and create ammonium bicarbonate. This resulting ammonium bicarbonate was converted back to ammonium carbonate in a regenerator and reused to repeat the process. The flue gas, cleaned of CO2, flowed back to the stack and the captured CO2 was compressed and sent for storage.
CO2 storage – Once captured, the CO2 was compressed into a liquid-like state and injected into porous rock layers approximately 1.5 miles beneath the surface. Monitoring wells helped verify and evaluate the conditions in the storage layers as CO2 was injected. Dense cap rock kept the CO2 from moving back to the surface.