During a stop on the campaign trail in 2008, Sen. Barack Obama told an audience in Lebanon, Virginia, “You can’t tell me we can’t figure out how to burn coal that we mine right here in the United States of America, and make it work.” Within months, an industry lobby group turned that speech into a rousing television ad for clean coal: “We can. We will. Join us.” The federal government accepted the invitation—in May, Energy Secretary Steven Chu allocated $2.4 billion in stimulus funds to “help position the United States to lead the world” in reducing coal’s greenhouse gas footprint.
From that resounding endorsement, it would seem that “clean coal,” an umbrella term for methods used to reduce coal pollution, is an easy fix for the world’s climate change woes. Proponents are particularly enthusiastic about a technology called carbon capture and sequestration (CCS), which would collect and store underground the carbon dioxide produced by the nation’s most abundant fossil energy source. Scientists envision capturing CO2 emissions and then trucking or piping the gas to a storage site with suitable geology. Once compressed, the gas would be injected thousands of feet underground, usually into a layer of porous rock. Over hundreds to thousands of years the CO2 would then turn into limestone or other minerals. Various studies suggest that there is space for between 2 and 10 trillion tons of carbon dioxide in geologic formations worldwide. California alone could store 1,800 to 6,600 years’ worth of emissions from its current power plants.