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2007 Nuclear Issues v29 11 |
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Written by Nuclear Issues
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Thursday, 01 November 2007 |
Nuclear Issues is also available as a pdf download
Thorium
We keep on being asked about thorium. It has long been recognised as an
attractive alternative nuclear fuel to the uranium-plutonium cycle. But
the thorium itself is not actually a nuclear fuel. It is a fertile
element which means that in a reactor it undergoes transmutation to
uranium-233. The uranium-233 is then a highly efficient fuel producing
on average 3 neutrons per fission rather than the average of 2.5
neutrons per fission as is the case with uranium-235 and plutonium.
Not many people realise that plutonium which is bred from uranium-239 in a reactor undergoes a significant amount of fission as it is formed in a reactor core. About 25 percent of the total energy produced in a fuel element during its spell in the core of a present day power reactor comes from plutonium without it having to be taken out of the core and reprocessed. In the same way the fission of uranium-233 produced from thorium accounts for the large proportion of the energy produced in a core with fertile thorium present.
This leads to many clever concepts in which the formation of uranium-233 can activate fuel in a core containing thorium before the poisoning from fission products becomes the most significant effect.
This is sometimes know as the seed-blanket effect as a blanket of thorium containing elements gradually takes over as the main fuel. A seed-blanket core was developed for the early pressurised water reactor at Shippingport in America under a project led be Admiral Rickover, the father figure of the US nuclear navy.
Year after year he appeared before Congressional committees to use his persuasive powers to get the budget renewed. But ultimately the environmentalists prevailed and indulged in their favourite passtime of pulling the reactor down.
Another early project was the Thorium High Temperature Reactor (THTR) project in Germany. This was to make use of the novel pebble bed reactor which circulated ceramic ball shaped elements through the core and offered the possibility of diverting thorium elements back into the core if they were active enough or eventually to waste containers. A small zero power reactor just outside the main power reactor was to have been used to measure the activity of the elements. But in an effort to get the project going the Germans initially adopted a uranium-plutonium fuel cycle. This was developed to the stage of a large 300 MWe THTR prototype reactor which actually operated for a few months before the destructive environmentalists finally got the upper hand and talked the project to death.
Now this reactor concept has been adopted by the South Africans as a small modular reactor which is also suitable for process heat production. We wish them luck.
Today, however, the only country pursuing the thorium-uranium-233 fuel line is India. This is because they have extensive deposits of thorium in the country and a neutron efficient heavy water reactor to eventually use the uranium-233. They are also building a prototype fast reactor which would be suitable for irradiating initial quantities of thorium. They have demonstrated the use of uranium-233 fuel but for the time being their nuclear programme is still based on the uranium-plutonium cycle. The thorium-uranium- 233 cycle is seen as a good long term prospect for ensuring independence of energy production.
The problem now is the time and expense of developing a new reactor system. Unfortunately the pedantic licensing authorities around the world will want a full scale prototype to operate for the extended life of the core. We may be confident of the long lifetime of a thorium element in the hostile temperature and radiation environment of a reactor core but the regulators will say: “show us.” Originally thorium looked attractive because we were not sure that there would be enough uranium. But now there is plenty for fifty years or more and very much more if fast breeders are used. And uraniumplutonium reactors are clocking up 400 reactor years of excellent operation each year.
Sure the thorium-uranium-233 cycle offers some reduction of waste and improves the proliferation resistance. But already the uranium-plutonium cycle produces ridiculously small amounts of waste and can be made quite proliferatio-resistant enough.
So we would say to the thorium enthusiasts: “keep the idea alive and watch the Indian work but don’t knock the clean, safe and economical reactors which we already have.”
Responsibility
According to Rudyard Kipling the exercise of power without responsibility is ... “the prerogative of the harlot throughout the ages”. But what of the alternative: who in their right mind would accept responsibility without the power to control events? Yet this is the approach of the Government to energy policy in insisting that decisions on the construction of new power plant must be taken by the industry. The Government can only tinker at the margins, sometimes doing more harm than good, through regulation, taxation and “setting the framework”, as with the expected decision in favour of the construction of new nuclear plants. They are unwilling to take any positive action (for fear of the Green lobby?) but insist that it is up to the initiative of the private companies to come forward with proposals for the Government to approve.
This is at a time when there is a high probability of widespread and damaging electricity shortages, in the event of a cold winter spell, an interruption of electric supply through plant breakdown, or problems with imported gas. A fundamental task of any government is to maintain the welfare of its citizens and protect the economic life of the country. The Government will be seen to have failed in this task and will surely be held responsible; they will not be able to shift the blame onto private industry.
It is accepted that with the planned progressive closure of the aging Magnox and AGR stations, and of the older coal-fired stations under the EU Large Combustion Plant Directive, the requirement for new electrical capacity will amount to about 30 GWe by 2016. It is far from clear if, or how this gap can be filled without an undue reliance on imports of gas and coal.
It is now unfortunately too late for new nuclear stations to come into operation before the 2016 date – particularly if any proposed design has first to be licensed by the Nuclear Inspectorate which could add up to a three year delay – but the crucial period could come sooner within the next few years. The electricity supply margins are already tight, and in the event of disruptions it is unlikely that the remaining generation would meet demand.
The recent unplanned shut-downs at Hartelpool and Heysham follow the almost continuous history of a falling output from British Energy’s nuclear stations since the ‘reconstruction’ and make it probable that further unexpected losses of capacity cannot be ruled out, which if they occurred during a cold winter spell would lead to widespread blackouts with social and economic chaos.
The response of the power companies has been to put forward proposals for Government approval to build more gas-fired and coal-fired stations, increasing the reliance on these fuels. In 2006 coal generated 37.5% of UK electricity with 36%.coming from gas. Gas stations have the advantage that they can be built relatively quickly for a lower capital cost. The disadvantage is that the fuel cost is high, amounting to about 60% of the electricity cost, almost twice the figure for coal at about 33%, (for a nuclear station the fuel is less than 20% of the total generating cost.) With the rapidly rising price of gas this has swung the advantage to coal; in 2006 coal firing was up by 12% while gas fell by 7% compared to 2005. This contributed to the 1.2 % rise in the UK carbon emissions.
The UK gas bubble has now burst. After a short-lived seve years as a net gas exporter between 1997 and 2004 we now import about 25% of consumption, a figure predicted to rise to 85% by 2015 and even to 90% by 2020. About one third of gas is used for electricity generation and another third for household use. With rapidly growing world demand for gas we cannot be certain that supply will keep pace with growing consumption. Global gas demand is expected to rise by 2.5-2.7%/y, with the big consuming area being Asia, where it has been suggested that demand will increase by an average of 3.5%/y between 2001 and 2025. But there can be no doubt that the price of gas will continue to rise steeply as it has in the past few years. This will not worry the power companies as they can, with Government acceptance, pass the fuel cost on to their customers. The possibility that supplies may be limited would however be disastrous.
As seen in the past year coal is now a cheaper alternative to gas. But here again the UK is becoming increasingly dependent on imports. In 2006 coal imports, at 50 million tonnes, met almost 75% of coal used in the UK. Domestic production was only 18.5 million tonnes a far cry from the 130 million tonnes mined in 1980. Coal prices on world markets are also increasing, dragged up by the increases in oil and gas and to meet the growing world demand. China the world’s biggest producer is now a net importer. An increased burning of coal and gas would be contrary to the Government’s climate change policy.
The Governments preferred option of supporting electricity from renewable sources is no more than a token offering to the environmental lobby. Even in the unlikely event that the target of 10% of supply by 2010 (20% by 2020!) is met it still leaves 90% to come from other sources. In 2006 electricity from renewables amounted to only 4.5 % of total electricity supply and of this half came from biofuels – municipal waste, sewage sludge and landfill gas – hardly the most environmental-friendly sources. Wind power, the flagship of renewable electricity, contributed only 4.225 TWh, about 1% of total supply, just over half the amount of net electricity imports. It is a sad reflection on the Government energy policy to consider that twice as much electricity might have been obtained from a second cable to France as from the much-touted programme of wind farms – and for a fraction of the cost.
Adding to the fears of serious power shortages arising within the next years, and certainly by 2016 there must be doubts whether the industry can bring the 30 GWe of new capacity required– some 40 % of present capacity – in a timely manner. Even with good luck, mild winters, available supplies of gas, and no serious breakdowns of the nuclear stations, so that blackouts can be avoided, the cost of electricity will inevitably rise in line with the increase in gas and coal prices. As it becomes less affordable there will be an increase in cold-related deaths for which the Government again will have to bear the responsibility.
An official estimate was that the total number of vulnerable households in fuel poverty in England would rise by around one million households between 2004 and 2006; the increase in the next years could be much greater. It is one of life’s ironies that Malcolm Wicks, the present Energy Minister, before he became an MP is said to be the author of a book on hypothermia and social policy.
How did we get into this mess
There is a long history of Government failure to ensure security of energy supply. In October 1998 in its response to reports from the Trade and Industry committee the DTI claimed that it was “unrealistic” to assume proposals for new nuclear plant would be put forward from commercial promoters so that “the contribution from nuclear is expected to decrease in tbe first decades of the next century ...” An expectation they viewed with equanimity. This passive, negative view was the basis of the Energy Review of February 2002 (from the oddly named Performance and Innovation Unit) which would go no further than recommending that the nuclear option be kept open but without any suggestions as to how this might be done.
The consequences of this policy were spelled out in a lecture of June 2002 by Robin Jeffrey, then chairman and chief executive of BE, in which he pointed out that on the DTI’s own projections the electricity fuel mix would be dominated by gas and suggested that the UK was at risk of stumbling into an energy crisis. His well argued case for “replacing nuclear with nuclear” as the older stations were retired obviously aroused deep hostility within the DTI which, contrary to the national interest of ensuring that the nuclear stations operated as base load generators, changed the rules of the electricity market to favour flexible supplies, more suited to gas-fired stations.
We can now see that Jeffries was right, and the then Secretary of State of the DTI was wrong. Had Jeffries - policy been adopted we would now be reaping the benefits of a secure electricity supply. Baseload nuclear power would be making small reduction in the UK fuel import bill as well as in emissions of carbon dioxide.
Could it also be possible that thermal stresses in attempts at load following to meet the new market rules might be a factor in the unplanned outages and some of the boiler problems of the AGRs which have contributed to the poor and declining performance of British Energy since the reconstruction? Nuclear stations should be run by engineers, not economists.
Now, when it has become even more obvious that future electricity supply can be at risk, the latest energy review report, The Energy Challenge, of 2006, took a more positive view: “Nuclear power is a source of low carbon generation which contributes to the diversity of our energy supplies. Under likely scenarios for gas and carbon prices, new nuclear power stations would yield economic benefits in terms of carbon reduction and security of supply.” The Government knows what has to be done, but is too fearful of the Green lobby to take any initiative.
Even now it still awaits the outcome of the latest ‘public consultation’. But the Government still remains passive.
The diversity and hence security of “our energy supplies” is clearly a matter of vital national interest, a responsibility which the Government will be unable to avoid, yet one it still determinedly refuses to accept – “it will be for the private sector to take decisions on proposing new power stations, based on commercial consideration.” It is far from obvious that the private sector will be willing to take on this task in time to bring any new nuclear stations on line to meet the probable power shortages. The major share of our electricity and distribution is now owned by foreign companies who will quite properly give priority to the interests of their own shareholders. They will first have to fund the construction of the 30 GWe of new capacity of coal and gas fired stations that will be required to maintain supply within the next ten years before they can contemplate the additional capital investment in new nuclear stations which will only come into operation after 2016. They will also be reluctant to accept any alterations to their proposed stations that may be required by the NII to meet supposedly higher UK safety requirements which would not only add to the costs, but lose the benefits of replication, building a series of stations to the same design. As has already been indicated it may be the case that any design built in the UK would be “to international standard or not at all.” And after the example of British Energy being brought low by the Government’s changes to the electricity market rules, any company contemplating building a new nuclear station would also require firm assurances from the Government of long-term stability before they risk the initial heavy capital investment they expect to provide secure returns over 50 years or more.
As things stand none of these matters will be resolved quickly. Unless the Government is prepared to take the powers it will require, to meet its responsibility for a secure electricity supply without further delay, the country will face a catastrophic economic and social collapse within the next decade.
There is little time left. Governments must occasionally do what they know to be right rather than what is merely popular.
Life after oil
We are now faced with two intertwined problems: climate change and peak oil. Solving one will at the same time lessen the impact of the other. So far attention has been solely focused on climate change. It is ideal material for politicians who can make high sounding declarations and take the credit for setting difficult targets for 50 years ahead secure in the knowledge that they will not be around at that time. Peak oil is a more urgent matter. We have only a few years to prepare for a world in which the hitherto continuous expansion of energy supply, which has driven economic growth and increases in world population, is coming to an end. Provided the catastrophe of more conflicts over access to resources can be avoided, which would only plunge the world into chaos, the task facing the international community will be in avoiding recession while adjusting to a new economic situation based on a stable or slowly declining energy supply. It is astonishing that while the world can enter into Kyoto agreements and set up international panels for the relatively distant problem of climate change the immediate problem of a declining energy supply is largely ignored. The problem it seems is too great and possible solutions too extreme for governments and authorities to bear thinking about. Let us shut our eyes and hope it goes away.
But it will not go away. And it would be wrong to take a too pessimistic view. It should be possible to accept a slow decline in oil availability. This may initially only be a matter of a few percent per year, with occasional brief upturns as new recovery technologies are introduced, so that it will be many years before oil finally runs out. An internationally acceptable scheme for oil sharing, perhaps on the lines of the ASPO Rimini protocol (see the above web site for details) would ease tensions between competing nations. There are also alleviating measures to reduce oil consumption which should be put in hand now, without the delay of waiting till the peak is, by hindsight, clearly in view. There are many ways, using available technologies, by which dependence on oil can be steadily reduced. In the absence of political leadership action is already stirring at the grassroots level. The Transition Towns movement of local communities “preparing for a carbon constrained energy lean world” is an example.
Movements towards localisation rather than globalisation would see an increase in local food production. In the absence of oil based fertilisers and pesticides organic farming will flourish but at the same time genetic modification may be required to produce disease resistant seeds. The immediate impact will be in finding substitutes for oil for road transport, but improvements in vehicle energy economy can be expected to continue as well as an increasing acceptance of hybrid or electric drive vehicles. Money spent on building new roads and reducing traffic congestion should be switched to improved and cheaper public transport systems.
These measures to reduce consumption of oil while necessary are, to an extent, only tinkering at the edges.
The prime need is to increase non-fossil fuel energy supply. In this nuclear power will inevitably play the major part, as the only reliable and sustainable and concentrated source of base load electricity and heat, that can be implemented on a sufficient scale to compensate for the reduction in oil. A return to a coal economy comes up against the other constraint of carbon emissions. Renewable energies, unpredictable and diffuse, can only make a minor contribution.
Construction of new nuclear stations can begin immediately using internationally accepted designs.
The aim for this country as well as the rest of the EU, should be to generate at least 80 percent of electricity in this way, as now in France.
Looking further ahead there could be more fundamental social changes. It is difficult to dispute the assumption that any further growth of the world population, now approaching 7 billion is unsustainable in a word of limited energy supply. Some even argue that a return to a pre-industrial level of around 1 billion would be preferable or even desirable. The question is how do we get from here to there. Without some extreme and unimaginable global disaster such a reduction is clearly not possible. A forced culling of the world population (a Babylonian lottery?) is obviously unacceptable. A slow decline over many generations is the best we can hope for.
Australian doubts
Whether Australia will develop a nuclear power industry may have been decided by the election which took place on 24th November, with the Conservative Party keen to develop Nuclear Power and the winning Labour Party opposing it. According to some Australian sources this Federal election was in effect a referendum on Nuclear Power in Australia.
During the campaign protestors disrupted the start of the Australian Nuclear Association conference and the speech by Ziggy Switkowski, chairman of the Australian Nuclear Science and Technology Organisation (ANSTO) in Sydney. Who said that the protesters’ views were not representative of the general population. “If we allow the debate to unfold, and make it fact based, I think we will see that the broader community will accept nuclear power.” Dr Switkowski was and still is pushing for 25 nuclear power plants that he claims would produce about a third of Australia’s energy needs reducing greenhouse emissions by a fifth.
So much for a fact based debate and what the general population felt. Some, too many, politicians seem to think that clean coal technology is the answer and what Australian should develop and convinced the voters of their case.
Professor Kurt Lambeck, a geophysicist at Australian National University criticised both main parties’ support for the development of clean coal technologies.
“There’s a lot of talk about clean coa – it could be construed as an oxymoron. The technological solutions that are being looked at are probably 20 years away before they can be really employed on the large scale.
The sequestration has its limitations, the capture of the CO2 has limitations, and it’s never totally clean anyway.” John Howard was a brave man to take on the nuclear mantle and it’s brave politicians that the nuclear industry needs. People like Pavvo Lippenen in Finland, who was prepared to argue the case and win it. One interesting difference between the Finland scenario and the Australian one. The Finns used a lot of women to argue the pro-nuclear case. In the macho world of Australian politics was it ever heard? |
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Last Updated ( Tuesday, 18 December 2007 )
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