Tuesday, November 18, 2008

Carbon Sequestration

The more I think about Carbon Sequestration the more it sounds to me like a really bad idea. People complain about burying nuclear waste--which is only more radioactive than the ore it comes from for about a thousand years. It even loses 99.9% of its radioactivity in the first forty years meaning that if something bad happens in say three hundred years, it would take thousands of reactors worth of waste to equal Chernobyl. Even that would require all of it to get vaporized into the atmosphere, a quite unlikely situation. Sure you have to be careful for the stuff, but it is almost completely composed of solids. Solids don't just dig up from a mile below the surface where they are encased in dry rocks. Even natural gas has trouble doing that.

Carbon dioxide however, that stuff stays deadly forever. There have been cases where CO2 from deep under ground has bubbled up and sufficated thousands of people! Unlike radioactive isotopes you cannot count on it getting any safer as time passes by. It is not very reactive, and like natural gas can just sit underground for millions of years. If that hole you dug to bury the output of a single coal plant happens to have a Volcano go right through it in twenty million years, you can count on it still being deadly and killing whatever rats and cockroaches have evolved into.

Even ignoring this, by definition the mass of CO2 from a coal power plant is about three times the mass of coal that goes in. When you consider we burn a billion tons of coal a year in America alone this is a stupendous volume of CO2 we are creating. I for one am not convinced that we even have sites for this much volume of gas/liquid if we ignored the safety risks.

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