(Spencer Platt/Getty Images)
Claim: Carbon capture and storage technologies will make coal a nearly zero-emissions energy source.
Reality: Coal-fired power plants add more carbon dioxide to the atmosphere than any other energy source in the United States, and they provide more than half of the nation's electricity. President Obama has devoted $4 billion to new clean coal technologies, specifically carbon capture and storage, or CCS, with the hope of making the source nearly emissions free. CCS is a process by which carbon dioxide is separated from the production process and stored beneath Earth's surface. Experts say this technology is years, even decades, away from widespread commercial viability, but one project shows promise.
In September 2009, American Electric Power's Mountaineer coal plant in West Virginia launched the largest CCS demonstration project in the world when it implemented a coal-fired system with underground CO2 storage. The company hopes to move ahead with a commercial-scale demonstration by 2015. But even if the technology proves successful, Gary Spitznogle, AEP's top engineer on the project, sees a potential problem. "Just because we can prove at Mountaineer that you can put CO2 in the ground doesn't mean that it's viable somewhere else," he says.
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