Coal presents another controversial topic for both depletion and emissions analysts. Most members of both groups feel a keen need to articulate some politically palatable transition strategy so as to gain the ears of policy makers. If coal were entirely ruled out of the discussion, such a strategy would become more difficult to cobble together. However, the two groups tend to think of very different future roles for coal.
Some emissions activists and analysts look to “clean coal” as a partial solution to the problem of Climate Change. “Clean coal” practices include gasifying coal underground, in situ, and then separating the resulting greenhouse gases (carbon dioxide and carbon monoxide) and then burying these in ocean sediments or old oilfields or coalmines This theoretically allows society to gain an energy benefit while reducing additions to atmospheric greenhouse gases.
Many depletion analysts are skeptical of such “carbon capture” schemes, believing that, when the world is mired in a supply-driven energy crisis, few nations will be adequately motivated to pay the extra cost (in both financial and energy terms) to separate, handle, and store the carbon from coal; instead they will simply burn whatever is available in order to keep their economies from crashing.
Some depletionists see the world’s enormous coal reserves as a partial supply-side answer to Peak Oil. Using a time-proven process, it is possible to gasify coal and then use the resulting gases to synthesize a high-quality diesel fuel. The South African company Sasol, which has updated the process, is currently under contract to provide several new coal-to-liquids (CTL) plants to China and has announced a plant in Montana. CTL is not attractive to emissions analysts, however. While some carbon could be captured during the gasification stage (at a modest energy cost), burning the final liquid fuel would release as much carbon into the atmosphere as would burning conventional petroleum diesel.
A few depletion analysts tend to take a skeptical view of future coal supplies. According to most widely-quoted estimates, the world has at least two hundred years’ worth of coal—at current rates of usage. However, factoring in dramatic increases in usage (to substitute for declining oil and gas supplies), while also taking account of the Hubbert peak phenomenon and the fact that coal resources are of varying quality and accessibility, leads to the surprising conclusion that a global peak in coal production could come in as few as 30 years (this conclusion can be extrapolated from a recent study for the DOE regarding the US coal supply).1 That raises the question: does it make sense to place great hope in largely untested and expensive carbon sequestration technologies if the new infrastructure needed will be obsolete in just a couple of decades? Imagine the world investing trillions of dollars and working mightily for the next twenty years to build hundreds of “clean” coal (and/or CTL) plants, with the world’s electrical grids and transportation systems now becoming overwhelmingly dependent on these technologies, only to see global coal supplies rapidly dwindle. Would the world then have the capital to engage in another strenuous and costly energy transition? And what would be the next energy source?"
Another look at coal comes from Phillip Deutsh, in an essay in Foreign Policy (November/December 2005). Deutsh makes the following points about coal:
"More than half of the electricity produced in the United States in 2004 was generated by coal. Total U.S. electricity sales [are] projected to increase from 3,481 billion kilowatt hours in 2003 to 5,220 billion kilowatt hours in 2025...no other energy source could fill this gap.
Wind and solar now account for less than 2 percent of U.S. electricity generation, and nuclear power only about 20 percent.Limiting coal also poses a dilemma for those who favor energy independence. . . .
If the United States were to cut back on its coal consumption, its current energy needs would require it to import even more oil, reducing the country's energy independence even further."
While Deutsch makes an unexceptionable point about coal and energy independence, he just ignores the danger of global warming. He asks, in effect: "why on earth can't people see the plain advantages of coal?" The answer: because they're paying attention to a factor that this sophisticated analyst simply ignores.
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