In late 2009, AEP confirmed its role as an industry leader in advancing carbon dioxide (CO₂) capture and storage (CCS) technologies when, along with its partners, it began operating the first fully-integrated CCS project at an existing coal-burning power plant. The project was one of several AEP initiatives to address the issue of climate change by reducing greenhouse gases and thus reaffirm coal’s ongoing role in fueling a reliable and affordable supply of electric power.

To date, AEP has participated in three projects to advance CCS technologies. All were conducted at the Mountaineer Plant, New Haven, West Virginia. The projects include:

• Geologic characterization studies, 2002 – 2004,
• Product Validation Facility, 2007 - present and
• Commercial scale project, 2009 – present.

Due to the current uncertain status of U.S. climate policy and the continued weak economy, AEP has made the business decision to place the project on hold until such time that economic and policy conditions create a viable path forward.

AEP has advised the U.S. Department of Energy (DOE) that it is terminating its contract with DOE and will put the project on hold upon completion of the project’s initial phase of front-end engineering and design. DOE had been funding 50 percent of project costs up to $334 million.

Between September 2009 and May 2011, the Project Validation Facility (PVF) validated the capture and storage technologies and confirmed that technologies can be successfully retrofitted on an existing coal-fired plant.

During its operating cycle, the PVF:

• Operated more than 6,500 hours
• Captured more than 50,000 metric tons of CO₂
• Stored more than 37,000 metric tons of CO₂.

By May 2011, the PVF successfully completed its objectives and discontinued operation according to plan. Lessons learned will be applied to future efforts.   

CO₂ capture – The Mountaineer Plant CCS projects employed Alstom’s patented chilled ammonia process for post-combustion CO₂ capture. The process uses ammonium carbonate to absorb CO₂ and create ammonium bicarbonate. This resulting ammonium bicarbonate is converted back to ammonium carbonate in a regenerator and is reused to repeat the process. The flue gas, cleaned of CO₂, flows back to the stack and the captured CO₂ is sent for storage.

CO2 storage – Once captured, the CO₂ is compressed into a liquid-like state and is injected into rock layers approximately 1.5 miles beneath the surface. Monitoring wells help verify and evaluate the conditions in the storage layers as CO₂ is injected. Cap rock keeps the CO₂ from moving upward.