A process called "carbon sequestration" may one day allow the United States and other countries to burn abundant coal reserves without emitting greenhouse gases. But the technology is far from complete, and some skeptics question its ability to effectively capture carbon dioxide. Learn more about the carbon capture process from leading researchers in the field.

"e²: the economies of being environmentally conscious" is an ongoing PBS documentary series about solutions to the world's most pervasive environmental challenges. The 2007 season opens with "e² energy", examining policy, consumption and viable alternatives to fossil fuel culture. Check your local PBS listings for television broadcast dates in your area.

The "e²" series and its video podcasts are produced by kontentreal, and distributed within the United States by PBS. More information is available at pbs.org/e2/ and e2-series.com/