Wednesday, February 28, 2007

Inherently safer nuclear (and free advice to the the Howard government)

Technology Review has an interesting article on "gen III & IV" reactors, which are basically designed to be simpler and inherently safer than current reactor designs.

As you may expect, pebble bed reactors get a mention, but so does another reactor (the Economic Simplified Boiling Water Reactor) which would, like Pebble Beds, could automatically shut down without any outside intervention:

The ESBWR replaces previous reactors' complex systems for residual heat removal with a design that uses no pumps or emergency generators--in fact, it possesses no moving parts at all, except for the neutron-absorbing control rods that are pulled partway out from its core so that nuclear fission can proceed. That fission reaction boils the water in the ESBWR's core, which becomes steam that gets carried away to large tubes in which it rises, releases its energy to turbines, and then condenses so that gravity causes it to flow back down to the core as water again. In short, the ESBWR runs wholly on natural circulatory forces. Rao says, "It could not be simpler. The control rods get pulled out, water comes in, and steam goes out, carrying heat that gets turned into electricity."

But even other, more complicated designs, are still much better than older plants:

This simplicity of design also features in other gen-III reactor designs like the Westinghouse AP1000, which has 60 percent fewer valves, 75 percent less piping, 80 percent less control cabling, 35 percent fewer pumps, and 50 percent less seismic building volume than currently operational reactors. This trend becomes more pronounced in gen-IV designs like the pebble bed reactor. In conjunction with "the modern computer-aided manufacturing technologies currently used most extensively in the ship-building industry," Peterson says, what's now possible is a modular approach to nuclear-plant construction, whereby large segments of the plants will be prefabricated in factories.

It seems to me that if the Howard government wants to defuse some of the Labor Party's "tell us where in Australia would you locate a reactor" scare campaign, it should be talking loudly about these new reactor designs which are safer, cheaper, and probably just becoming available when we would want our first reactor anyway.

It may be premature to do so, but it could be even better to commit to only allowing reactors with strong passive safety, such as a pebble bed or that ESBRW described above. I mean, if the thing can't melt down, even if something goes wrong while everyone is at the Christmas picnic, that has to be a strong selling point in the public's mind.

This aspect of the future of nuclear power generation is not getting the publicity it deserves.

My other advice to John Howard: it's not too late to get rid of that goose of a Defence Minister Brendan Nelson.

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