Thursday, September 08, 2005

Nuclear Confusion

Australian Financial Review -

Nuclear confusion
Jun 24
David Fleming | Prospect Magazine


There are two things to be said for nuclear power. It is based on an energy process which does not produce carbon dioxide. And it is a way of generating energy which is not directly at risk from the looming scarcities affecting oil and gas. These two killer arguments tend to be conflated into one persuasive and rhetorical question: "What's the alternative?"

There are arguments against it too, and most of them are well known. It is expensive and, without hefty government subsidy, offers little potential for profit. It leaks low-level carcinogenic wastes into the air and water. It produces high-level radioactive waste, requiring standards of treatment and storage which are seldom met. It produces the materials for nuclear proliferation. Its accidents can potentially devastate continents.

But there are two other arguments against nuclear power that are not so well recognised. The first is that nuclear power actually produces quite a lot of carbon dioxide: every stage in the process uses fossil fuels (oil and gas) - with the exception of fission itself. Uranium ore has to be mined and then milled to extract the uranium oxide from the surrounding rock; it has to be enriched; the wastes have to be processed and buried, safely; nuclear power stations have to be constructed, maintained and then eventually chopped into bits and stored away.

But it is the second argument which shocks: nuclear power depends on a supply of uranium ores from scarce, rich deposits, which face a depletion problem every bit as serious as that of oil and gas. That rich ore will soon no longer be available. The poorer grades of ore that would then have to be used take more energy to process than they yield.

The question of how much rich uranium ore is left would not matter if the industry were to continue on its present small scale. So the question is: what job is nuclear power likely to be asked to do? A serious contribution - enough to make a difference - might mean bringing on nuclear power to replace the gas and coal now used to generate electricity. A more ambitious one - but necessary, given the scale of our energy problem - would be to provide the primary energy to generate the hydrogen that we would need to replace the use of petrol and diesel on road and rail. If nuclear power did all that, then gas could be reserved for the jobs it does best - providing fuel for industry and households. If applied worldwide, this would, in principle, solve the energy problem for some years to come.


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That would, of course, mean a renaissance for nuclear power. But what else would it mean? The waste problem would increase, and the nuclear industry would be forced to meet impeccable - but energy-consuming - standards of waste management, treatment and storage. It would also have to rehabilitate landscapes after they had been mined for uranium. All this would bring forward the point at which the industry would be forced to use ever poorer uranium ores as the richer ones were depleted - and its need for energy from fossil fuels to extract the uranium would start to rise quickly.

It is not the mining process that makes the really serious demands for energy, but the milling. All too soon, it would be necessary to mill hard ores with a uranium oxide content of 0.02per cent - that is, one part in 5000: for every tonne of uranium oxide they extracted, the industry's raw material suppliers would have to mine, mill and dispose of some 5000tonnes of granite. At the same time, it would be reduced to milling soft ores (sandstone) with a uranium oxide content of just 0.01 per cent - 10,000 tonnes of ore to be mined, milled and disposed of for every tonne of uranium oxide extracted.

It is with ores at these grades that nuclear power hits its limits; this is where the energy balance turns against it. If ores any poorer than this were to be used, while at the same time maintaining proper standards of waste control in all operations, nuclear power production would go into energy deficit: it would be putting more energy into the process than it could extract from it. Its contribution to meeting the world's energy needs would become negative.

At present, nuclear power is not one of the major producers of energy. It accounts for about 16per cent of the world's electricity supply, which in turn accounts for about 16per cent of all the energy produced, so that its total contribution to the world's final energy needs is about 2.6per cent. Suppose, however, that the industry were to be set up on a scale large enough to make a difference. For how long could it continue to provide the needed energy before, for practical purposes, it had used up all the uranium ores rich enough to produce a positive energy balance? If it supplied the world with all its electricity, then the total quantity of useful ores on the planet would be sufficient to keep the nuclear industry going for just six years. If, in addition, the world's road and rail transport fleet were to be run on hydrogen derived from nuclear power, then the useful life of the industry would be about two years. As provider of a few token reactors to show that governments are trying, it could keep going, rather pointlessly, for another 40 years. But the essential fact is this: as a serious new source of energy, nuclear power is a non-starter.

Most of the analysis in this field is being done by Jan Willem Storm van Leeuwen and Philip Smith, both nuclear scientists at the end of distinguished careers, now free of the need to appease any institution, and with the courage to cope with a great deal of criticism and worse.

There are three criticisms of the uranium shortfall thesis. First, it is argued that there are plenty of good-quality uranium deposits available, that reserves are abundant, and that they will become more so when demand strengthens. But there is little to support this. From the 1960s to the 1980s, exploration for uranium deposits was intensive; most that was there to be found was found. Some small deposits doubtless remain to be discovered, but the geology of uranium is now well known: there are almost certainly no major new discoveries ahead.

Second, critics point out that uranium is an abundant element; there is plenty of it in the earth's crust and in seawater. But in both cases the energy needed to extract it would be more than could ever be recovered.

Third, there is the argument that we could use uranium more efficiently by developing breeder reactors, which would be 100 times as efficient as today's thermal reactors. But after 50 years of extremely expensive research, they are still not technically feasible.

As long as the argument remains bogged down at the level of whether the problem exists or not, governments will consider themselves free to do exactly as they want. They will insist that there is no alternative to nuclear power, and nuclear power stations will continue to be built in Britain and around the world - enough to provide a general sense that help is at hand, but not enough to have any positive effect on the problem of energy and climate change. What will be significant will be the negative consequences. An expansion in the nuclear power industry will suck up the funds which should be made available for conservation and renewables. It will be a source of low-level radiation, of materials for proliferation and of carbon dioxide emissions. It will produce some very expensive energy. And then it will hit its limits. The industry will be left with huge reserves of low-grade uranium ores, too poor to be usable, and an equally huge inheritance of contaminated waste which has to be dealt with.

Just at the moment, we have an opportunity. Very efficient, manageable, small-scale solutions - focused on renewables and conservation technologies comprehensively applied - do exist. They need single-minded planning, big investment and training programs; but they have the advantage that, unlike any other option, they are feasible; and they do not conceal within them some terrible snag that no one dares talk about. There could be real solutions to the rapidly unfolding energy crisis. If sacrifices are now made to the voracious demands of nuclear power, that chance will be lost.

David Fleming's book The Lean Economy is forthcoming.

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