Coal is the black sheep of the energy family. Uniquely abundant among the fossil fuels, it is also among the worst emitters of greenhouse gases. Mindful of coal’s bad reputation, President Bush promised the world three and half years ago that the United States would develop a superclean coal plant in an initiative known as FutureGen. The plant would have zero emissions; even the carbon dioxide it released would be pumped underground.
Today there is a patch of land in Great Bend, OH, where an advanced coal plant may one day be built. The plant could eventually include equipment for siphoning off carbon dioxide. But it’s not FutureGen, which today remains a collection of research projects. No FutureGen plant has been constructed, and no site for one has been chosen. The proposed plant at Great Bend could more appropriately be called “PresentGen.” The technology involved doesn’t demand a White House neologism suggesting that clean coal is something for which we must wait.
Great Bend is owned by American Electric Power (AEP), the largest coal-burning company in the United States. The company proposes to build what’s called an integrated gasification combined-cycle (IGCC) plant. IGCC is frequently referred to as a “new technology,” but it’s really a combination of two well-established technologies – both of which are also intended for FutureGen. The first is gasification, in which coal is partly combusted under carefully controlled temperatures and pressures and turned into a concentrated “syngas” of mainly carbon monoxide and hydrogen. (From syngas, impurities such as sulfur dioxide can readily be removed.) The second is the “combined cycle” – the electricity generation technology already ubiquitous in natural-gas power plants, where turbines are driven both by a stream of gas and by steam produced from waste heat. Most importantly, carbon dioxide can be captured from a gas stream far more easily than from the smokestacks of a conventional coal plant.
IGCC plants are vastly more advanced than today’s pulverized-coal plants – which are planned in ever larger numbers around the world – but they’re hardly futuristic. “We’ve done a pretty thorough due diligence on the technology, and we didn’t casually come to the conclusion that IGCC was ready,” says Robert Powers, AEP’s executive vice president for generation. “Gasifiers have been used since the turn of the last century, in a crude sense, and used in the petrochemical industry and refining industry for years. And certainly, on the generating end of the plant, combined-cycle combustion turbines – we own combined-cycle combustion plants now. Each of those pieces is a mature and developed technology.”
Indeed, coal gasification, developed about a century ago, has long been the technology of last resort for countries unable to gain access to oil. The Nazis used it to fuel the Luftwaffe; South Africa adopted it during apartheid. In North Dakota, a coal gasification plant went online in the early 1980s after the Arab oil embargo, later began capturing and selling its carbon dioxide for use in oil recovery, and is still humming today.