Saturday, November 04, 2006

Pulverized Coal VS Coal Gasification

Some 154 new coal-fired plants are on the drawing board in 42 states in the US. Should power companies be permitted to build new plants that pollute more but are reliable and less expensive? Or should regulators push utilities toward cleaner burning coal plants, even if it means they will cost more and are based on newer, yet still unproven, technology?

These are the points that an online article by Time/CNN discuses. The discussion is focused on whether pulverized coal units or coal gasification plants should be built. The article states that coal gasification plants are 20% more expensive to build, "but they also can be more efficient to operate and save utilities the hassle and expense of adding pollution-control devices." Not quite correct, in that pulverized coal plants can be built to clean coal standards, but gasification plants can achieve even lower emissions of criteria pollutants. Gasification plants can be adapted to carbon (CO2) capture much less expensively than pulverized coal plants but at a cost more than the 20% factor which does not include carbon capture. However gasificaction plants produce about 33% less CO2 emisions due to their higher efficiency. I would disagree with the premise stated above that gasification technology is unproven, although not proven to the extent that pulverized coal plants are. A few gasification plants are under construction and several are under development. The article does not discuss whether renewable energy or nuclear energy should be considered. The two main points of the discussion are illustrated by these two exerpts from the article:

(utilities are) driven by profits and are rushing to beat more stringent federal restrictions on carbon dioxide emissions in an era of escalating concerns over global warming.

Mike Morris, chairman for American Electric Power, said the pressures on power companies to burn fuel in the cleanest way possible will only gain momentum in coming years. "From our vantage point we think the technology for clean coal is there," he said. "It can be done, but there is a challenge." For it's part, TXU says turning the coal into synthetic gas remains an unproven technology and not as reliable as burning pulverized coal — the process the company's new plants would be designed to use.

TIME/CNN Article

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