Nuclear power plants have often been touted as a solution to the problem of climate change because they emit no carbon dioxide. A moribund nuclear power industry hopes that this feature can rescue it from the dustbin of history. Congress is considering vast subsidies for nuclear power - once advertised as "too cheap to meter."

But climate change may kill the nuclear industry's hopes before it can conquer climate change. A severe drought last August in France, the nuclear power capital of the world, is the bearer of this bad news. It has cast doubt on the future reliability of France's electricity supply.

Like many nuclear power plants around the world, dozens of French nuclear reactors use huge amounts of river water for cooling. But the drought severely reduced the available water last August. Without enough water, the power output of some of these reactors had to be cut back, even as people were frantically buying up air-conditioners to keep cool. France gets about 80 percent of its electricity from nukes.

We can't really pin any particular event to climate change. But extreme phenomena, like 100 year floods in parts of India, the rapid melting of glaciers from Africa to Alaska, and the unprecedented heat and drought in much of Western Europe this year, have become much more frequent. Bark beetles are multiplying far more rapidly than usual in drought-ridden areas in the Western United States; they are destroying forests and raising the risk of fires. There is now ample evidence that greenhouse gas emissions have seriously upset Mother Nature's tolerant and accommodating balance.

Many problems arising from climate change have been researched and much discussed. But this particular problem - a negative spiral of diminishing water supplies and diminishing electricity supplies strangling society - is not one of them. It is essential that discussions of energy policy take note of it.

Fortunately there are sources of electricity that emit no greenhouse gases and use no cooling water at all. Examples include wind power, solar cells, tidal plants, and plants that tap wave energy. The wind energy potential of 12 mid-western states, including North and South Dakota, Texas, and New Mexico equals three times the entire electricity output of the United States.

If you want to know more about nuclear power, renewable energy, and efficiency, visit the website of the Institute for Energy and Environmental Research, www.ieer.org. This is Arjun Makhijani.

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