Tim Pinkston has built a massive chemistry set in the middle of a longleaf pine forest in eastern Mississippi. “I’m so happy to see it come to fruition,” says Pinkston, a rangy engineer with owlish eyes, during a tour of the Kemper County Energy Facility on a warm summer morning.

Standing on a large expanse of flat land that has been clear-cut and paved with concrete, he is pointing to a vast complex of twisting, turning pipes, hundreds of miles in all, that surges skyward. At the center of this cross between a chemical factory and a power plant are two towering silos more than 300 feet tall. The twin gasifiers, each weighing 2,550 tons, can create the heat and pressure of a volcano. That is what is required to take lignite, a wet, brown coal mined from almost underneath Pinkston’s feet, and turn it into gaseous fuel that is ready to burn to generate electricity.

What makes this chemistry set extraordinary is not the fuel it will soon produce but how it will handle the chief by-product: carbon dioxide, the greenhouse gas behind global warming. Rather than send the CO2 up a smokestack and into the atmosphere, as conventional coal-fired power plants do, Pinkston and his colleagues at Kemper will capture it. ...