Do coal fired power stations produce radioactive waste? © Getty Images

Do coal-fired power stations produce radioactive waste?

Them pesky greenhouse gases might not be the worst thing coming out of fossil fuels.

Asked by: Anonymous

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Yes – and the waste contributes far more radiation to the environment than nuclear power stations. The radioactivity comes from the trace amounts of uranium and thorium contained in coal. These elements have been trapped in the Earth’s crust since its formation and are usually in concentrations too low to pose any serious threat. But the burning of coal produces fly ash, a material in which the uranium and thorium are much more concentrated.

The exact amounts depend on the source of the coal, but are usually in the range of a few parts per million. That might not sound a lot until you realise that a typical gigawatt-capacity coal power station burns several million tonnes of coal per year. That means every such station creates fly ash containing around 5-10 tonnes of uranium and thorium each year. Multiply that by the number of such stations worldwide and the total amount of radioactive waste produced is truly astonishing.

According to estimates by the US Oak Ridge National Laboratory, the world’s coal-fired power stations currently generate waste containing around 5,000 tonnes of uranium and 15,000 tonnes of thorium. Collectively, that’s over 100 times more radiation dumped into the environment than that released by nuclear power stations.


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