Friday, September 25, 2009

It Ain’t Coal-Ahhhh!

Is it a dead horse that I’ve beaten once too often – that there really is no such thing as “clean coal”? Or is this anthracite topic worth dredging up one more time? I know that the U.S. would love to have such a beast – after all, we are the “ Saudi Arabia of coal” – but we really have to bury our heads in the sand… er coal tar… the live in that mythical world.

Oh, it is possible to burn coal completely, leaving recyclable residue, but that process is hardly commercial; what we’re trying to get the rest of the world to believe is that we can take the greenhouse gasses that are generated from coal-fired power plants and compress them into the ground in old wells, dry aquifers, and abandoned mines and oil fields… to be dealt with later, when someone figures out what to do with the mess. It looks clean as long as you don’t look at what is hidden underground… kind of like reverse smoke stacks… polluting into the earth.

The eyes of the world – at least the energy world – are all on the Mountaineer coal-fired power plant in New Haven, West Virginia… right on the Ohio border. You see this little beauty, an old smoke-belcher (built in 1980) was retrofitted with a carbon capture technology that will take a large “chunk” of carbon dioxide emissions and shove them deep below the surface, perhaps for thousands of years.

The September 22nd New York Times describes the process: “If all goes smoothly… engineers will begin pumping carbon dioxide, converted to a fluid, into a layer of sandstone 7,800 feet below the rolling countryside here and then into a layer of dolomite 400 feet below that. The liquid will squeeze into tiny pores in the rock, displacing the salty water there, and assume a shape something like a squashed football, 30 to 40 feet high and hundreds of yards long. American Electric Power’s plan is to inject about 100,000 tons annually for two to five years, about 1.5 percent of Mountaineer’s yearly emissions of carbon dioxide. Should Congress pass a law controlling carbon dioxide emissions and the new technology proves economically feasible, the company says, it could then move to capture as much as 90 percent of the gas….

“For now the project consists of the two wells and a small chemical factory. In the factory, smoke diverted from the plant’s chimney is mixed with a chilled ammonia-based chemical. The chemical is then heated, releasing the carbon dioxide, which is pumped deep into the wells.” Not that this is particularly cheap; the cost of the carbon capture part of this process is reported to be around $73 million, and experts believe that the pumping and conversion equipment cost over $100 million.

Why does this seem a bit like sweeping your carpet clean but storing all the dirt, every time you sweep, under that carpet? Scientists suggest that this is an interim technology (like this is really a technology worthy of labeling it a technology!) that will be solved as we evolve better methods of electrical power generation. I guess if you can’t see it… it’s not there. Better than nothing, I guess, but a pretty sorry state of engineering for a nation like the United States to tout.

And you may have noticed that the above process involves pumping and converting. And you may be wise enough to know that those efforts require… er… you got it… energy. And well, this is an energy-generating plant, so that of necessity, its efficiency will be compromised by the loss of energy needed to pump and convert – somewhere between 15% and 30% of the plant’s total output, depending on whom you talk to.

As officials from foreign power companies – some having come from as far away as India and China – have arrived to watch the plant apply this new technology, clearly there is a lot at stake. Why am I not thrilled with this expensive and inefficient “sweeping under the rug” technology?

I’m Peter Dekom, and I approve this message.

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