Dwindling Coal Reserves and the Siren Song of 'Clean Coal'. By David Roberts, HuffPost, July 28, 2009. "There isn't nearly as much coal left as most people think. 'Clean coal' will run down limited reserves even faster. If humanity doesn't begin massive, sustained investment in renewable power sources immediately, civilization could be at risk before the end of the century. And that's without considering the impacts of climate change. Such is the stark conclusion of Richard Heinberg's Blackout Coal, Climate and the Last Energy Crisis, which despite its dry tone and technical complexity is one of the scariest... books I've ever read... If Heinberg is right, policymakers are operating under two fateful, and possibly fatal, illusions...
"First, they think the U.S. has a '250-year supply' of coal, and that China, Russia, Australia, and India have similarly inexhaustible supplies. They're almost certainly wrong.The bulk of Heinberg's book is a methodical walk through several recent studies on coal reserves. (One of the most shocking facts about coal reserves is how little we know about them -- they were scarcely studied in any systematic way before 2005.) If you have time for just one, check out Coal: Resources and Future Production [PDF, 47 pp], by Germany's Energy Watch Group. It's a page-turner!... The easiest reserves are found first. Over time, as more accessible seams are mined out, what remains is increasingly difficult to obtain and expensive to transport. In every coal field, every country, every region, the energy-return-on-investment (EROI) rises, peaks, and declines. Post-peak, it takes more and more energy to reach the coal and get it where it needs to go. The crucial issue is not how much coal is left in the ground but where we are on the curve, and more to the point, when we cross into negative EROI, the crucial line after which it takes more work to get coal out of the ground than coal returns in energy...
"The second fateful illusion: that carbon capture and sequestration can enable the continued expansion of coal use. Industry insiders admit that CCS technology will not be developed, and costs reduced enough to prompt widespread adoption, until 2035 at best. By then... when supplies are declining, while commodity and transportation costs are rising, we'll need much more coal to get the same amount of electricity from a more expensive generation technology.Surely you see the wisdom of the strategy... At minimum, a sustainable future requires the best possible understanding of available coal reserves and their likely cost. If 'clean coal' turns out to be a phantom, chasing it will not only waste time, it may foreclose the only decent options we have left."
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