A problem technology can’t fix



The most dangerous thing about the possibility of using nuclear fusion to generate electricity is that it encourages us to believe that we’re not at the end of the road we’re traveling. That there can be a technological fix to save us from environmental nightmares that loom ever closer.

Fusion is what powers the sun, where intense heat and crushing, gravitational pressure force nuclei of different elements to combine, thereby releasing tremendous energy. By contrast, Canada’s nuclear generating stations rely on fission, the splitting of nuclei, to release energy. The major difference for electricity generators is that fusion, unlike fission, produces no radioactive waste.

Four international partners — Canada, the European Union, Japan, and Russia — want to build a fusion reactor for research that they call ITER (ee-ter) for International Thermonuclear Experimental Reactor. The big question is: Where would it be located?

A Canadian consortium wants it built in Ontario at Clarington, right beside the Darlington nuclear generating station. In the consortium are four federal government departments, the Ontario government, Ontario Power Generation, labour unions, major engineering and construction firms, and the Royal Bank.

With a price tag of $12.5 billion, ITER would be the largest international project after the space station.

There would be risks, of course. As with any project, there will be accidents. Tritium and deuterium are the fuels whose nuclei would be fused, and tritium, the waste product from Canada’s reactors, is radioactive and deadly. It causes cancer, birth defects, and with sufficient exposure, death.

ITER would take eight to ten years to build, and would operate for 20 years, using 15 to 20 kilograms of tritium. That’s enough to kill three to four million people if the minimum lethal dose were ingested by each person. Tritium, in its elemental form, is a gas.

However, say consortium officials, there’s no cause to worry, because only a few grams, would be used at any one time in the reactor. If anything went wrong, the fusion process would simply shut down. The end products would be helium and energy.

The process would, however, irradiate the reactor. Dave Martin, nuclear policy advisor to the Sierra Club of Canada, estimates it would create more than a thousand times more radioactive debris than Darlington would produce as waste in the same period.

To mimic the sun, the reactor would need to create temperatures reaching 100 million degrees Centigrade. That’s so hot that no container could hold the tritium and deuterium without melting. So the fuel would be suspended by electromagnets. To approximate the gravitational force of the sun, the magnets would have to be super-cooled at close to absolute zero, minus 273.16 ° C.

The magnets, a Russian design, would be in the shape of a huge donut, suspending the tritium-deuterium plasma in the centre of the hole in the donut.

ITER would be the single highest-volume customer of Ontario Power Generation, requiring a constant supply of 100 megawatts of electricity, plus bursts of 500 megawatts several times a day. Darlington produces 4,000 megawatts, 20 per cent of Ontario’s electricity.

Murray Stewart, managing director of the Canadian consortium, says ITER research could save the environment by creating a replacement for coal fired generating stations, which account for more than half of the world’s present generating capacity, and for most of the new capacity as developing countries industrialize.

However, at the heart of ITER is the assumption that we can have business as usual, with a measure of restraint. But that’s wrong. The carrying capacity of the Earth is at its limit now.

Without radical change, we risk everything. I think we should be concentrating on chopping by half the amount of electricity we need from massive generating stations.  We need to consume much less, waste much less.

As Pogo used to say in the old comic strip, “The problem is us,” and technology isn’t going to fix that.

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