Wednesday, December 21, 2005

John Busby - Australian News Opinion Reply

Nuclear power: no solution to climate change
By Jim Green - posted Tuesday, 6 December 2005
http://www.onlineopinion.com.au/view.asp?article=3906
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There is no "nuclear option", because the world is running out of economically-mined uranium and the secondary supplies of ex-weapons highly enriched uranium (HEU), re-worked mine tailings, inventories and a modicum of MOX are expected to be exhausted in ten years or so.

This is so much a crisis for the nuclear industry that it has anguished over it in the last three annual symposiums of the World Nuclear Association in London. Many nuclear stations will run out of fuel once the 40% of the world's supply from secondary sources declines.

Primary mining supplies provide only 60% of the demand and even this level of supply requires a constant location and opening of new mines as the production in the existing mines reaches its "Hubbert" peak and then declines.

There could be no better illustration of this dilemma than the proposals to expand Olympic Dam mine in South Australia by digging a hole 3km x 3km x 1km to extract copper, gold and uranium. BHP Billiton has initiated a feasibility study, but have already stated that without the copper, the grade of uranium ore at only 0.04% is insufficiently high to warrant a go-ahead without the revenue from the copper.

Uranium is mined for the energy it produces in a subsequent nuclear fuel cycle, but if the diesel and electricity used to excavate such an enormous hole and mill the lean ore exceeds that produced in the fuel cycle what is the point? The Olympic Dam expansion requires desalinated water supply and pipeline, a rail connection and there is a suggestion of an airport. The initial energy input is unlikely to provide a decent energy return, certainly not if world recession lowers the price of copper.

The proponents of the "nuclear option" should state where they imagine the world's uranium supply would come from, especially if Australia retained its uranium for its own fleet.

Posted by John Busby, Wednesday, 7 December 2005 3:32:56 AM
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anti-green quotes UIC paper 75, but nothing could undermine the case for nuclear power more!

It gives the concentration of uranium in seawater as 0.003 parts per million, so with an optimistic yield of say 50% it would require the processing of 1,000,000 x 2/0.003 = 667 million cubic metres of seawater to obtain 1 tonne of uranium with huge pumping energy.

UIC75 gives the average of uranium concentration in the earth's crust as 2.8 ppm (0.00028 %), so with a ratio to overburden to ore of 3:1 and a yield of 10% it would take the mining and milling of 1,000,000 x 10 x 3/2.8 = 10.7 million tonnes of rock to get 1 tonne of uranium. At the mine and mill the principle fuel is diesel, so as fossil fuels get scarcer the level of extraction energy rules.

UIC75 argues that a rise in the price of uranium could be readily carried in the price of electricity, but the killer factor is the enormous increase in the energy needed to extract the uranium from low concentration resources. If the input energy in the overall nuclear fuel cycle exceeds the electrical energy obtained therefrom, the entire operation is pointless. Only the limited high grade reserves in Canada give an adequate energy gain, but to maintain its current production requires continuous prospecting and opening of new mines, the finding of which cannot be guaranteed.

UIC75 mentions military warheads, but the supply of ex-weapons HEU is running out. It admits that thorium is not in commercial use, nor is there a commercially available fast breeder reactor.

anti-green mentions the recent WNA paper on "The new economics of nuclear power". It needs new economics because the old ones have failed. There is no margin to pay for waste treatment. In the USA spent fuel remains on site at 72 of the 100+ power stations which has to be kept stirred and cooled in ponds to avoid a melt down.

anti-green will need better than UIC75 to convince me that nuclear power is viable.

Posted by John Busby, Tuesday, 20 December 2005 4:00:19 AM
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* See also: NucNews Links and Archives (by date) at :
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