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2006 Nuclear Issues v28 01 |
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Written by Nuclear Issues
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Sunday, 01 January 2006 |
Nuclear Issues is also available as a pdf download
More nuclear myths
Energy accounting
Suggestions that the energy used in constructing a nuclear power station and in supplying the fuel over its operating lifetime could be greater than the total energy the station produced first surfaced in the 1970s and were at that time comprehensively rebutted. A related issue argues that a nuclear station emits more carbon dioxide during its lifetime than it saves. Although these questions were debated again at the 1990 Hinkley Point Inquiry, they were again shown to be based on untenable assumptions. Indeed the FOE witness on this issue accepted that using uranium enriched by gas centrifuges (which consume only about 5 percent of the electrical energy of a diffusion plant) the annual carbon dioxide emissions from a PWR would fall to 21 000 tonnes – less than half of the figure proposed for their wind plant.
Now, no doubt with the forthcoming Energy Review in mind, the matter has surfaced again: in the House of Lords by the Liberal-Democrat spokesman Lord Redesdale. But since the Hinkley Point inquiry the only new claim appears to be in a paper in 2002 by van Leeuwen and Smith in the Netherlands, whose analysis has been widely criticised as based on worst case assumptions, (including as in the FOE paper of 1990 that enriched uranium comes from a diffusion plant powered by electricity generated by coal rather than from the more energy-efficient centrifuge plants.
An alternative analysis by the Swedish State Power board (Vattenfall), based on their Forsmark nuclear station over a projected 40 year lifetime, finds that taking account of the energy used in construction of the plant, mining the Uranium, enriching it, converting it to fuel, disposing the waste and decommissioning the plant, the energy input to the Forsmark Plant is only 1.35 percent of the lifetime output. The carbon dioxide emissions from the nuclear plant are put at 3.1 g/kWh, slightly below that for wind at 5.5 g/kWh, but both are very much lower than 980 g/kWh for coal or 450 g/kWh for gas combined cycle. There are other studies from a number of different countries which all show the emissions from nuclear, wind, and photovoltaic at about the same very low level.
This is precisely the conclusion reached by the Inspector at the Hinkley Point inquiry in 1990 – “it can be reasonably argued that the average annual carbon dioxide emissions resulting from the operation of a PWR would not be dissimilar to those from the operation of renewable sources producing an equivalent electrical output and would be of the order of a few percent of those from a conventional coal-fired plant.”
Uranium supply
Another contentious claim by van Leeuwan and Smith was that high grade uranium ores would be exhausted within a few years and thereafter the mining of much larger quantities of low grade ore would consume everincreasing amounts of energy. As discussed in NI (December 2005) available conventional uranium resources are likely to last for centuries, but there are in addition a number of other potential sources of supply which would be used more widely if, to meet the extra cost of processing low grade ores, the price of uranium were to rise.
Reprocessing spent fuel will recover the unburnt uranium which amounts to over 95 percent of the original uranium in the so-called “waste”. This can be recycled to manufacture of new uranium fuel by combining it with plutonium, also recovered in reprocessing, as mixed plutonium/uranium oxide fuel. MOX fuels are now increasingly deployed in reactor cores in many water reactors. There are now a number of MOX suppliers, including the BNFL plant at Sellafield, to meet the growing demand.
The development of breeder reactors, which while burning plutonium enriched fuel would breed more plutonium in a blanket of fertile uranium placed around the core, would enable the large stock of depleted uranium ‘tails’ left over in the enrichment process to be utilised. This would be a more productive use for the 1.2 million tonnes or so of depleted uranium held in store than its present use in conventional military munitions. Although the UK prematurely abandoned the fast reactor development which was being carried out at Dounreay, breeder reactors are an important part in the long term nuclear programmes of Russia, Japan and India. In Russia after 21 years of faultless operation of the BN-600 reactor the construction of an 800 MW version, BN-800, is planned for operation by 2009.
Breeder reactors are also the most efficient way of using the surplus of plutonium and highly enriched weapons-grade uranium now available from the decommissioning of nuclear warheads, which will (we perhaps optimistically expect) become increasingly available as the existing stockpile of nuclear weapons is decommissioned and not replaced. Already the equivalent of 9000 nuclear warheads have been converted to fuel for commercial reactors. A total of 22.5 tonnes of weapons-grade uranium has been sent from Russia to the USA for down-blending with depleted uranium to low enrichment material which can be used by US utilities in their nuclear power plants. By 2013 it is planned that some 500 tonnes of weapons grade uranium will have been recycled in this way. The US Department of Energy is also down-blending much of its stockpile of highly enriched uranium.
Ultimately, from figures given in a report by the OECD/NEA Trends in the Nuclear Fuel Cycle: economic, environmental and social effects, the natural uranium in the worlds oceans could be by far the largest uranium resource available – a staggering 4 billion tonnes. Of course, as this is dissolved in a vast quantity of water the uranium concentrations are low. But as the report points out extracting uranium from sea water is feasible. Costs would be high, (although most of the energy required would be met by tidal flow), and are estimated at about 10 to 25 times present uranium prices. Since natural uranium represents only about 5- 10% of the forward cost of nuclear electricity, extraction of uranium from seawater would provide a virtually unlimited supply while only doubling the cost of electricity from present reactor types. The cost penalty would be lower with more advanced reactor types while the introduction of fast breeders would create a truly sustainable and pollution-free energy resource.
The element thorium, four times more abundant in the Earth’s crust than uranium, can also be used as a nuclear fuel. Although not a fissile element, thorium can be converted in a reactor to fissile uranium-233. This is the basis of the Indian nuclear power programme which intends to utilise the large thorium deposits in the monazite sands of Kerala. A 500MW fast breeder reactor using a uranium-plutonium carbide fuel will have a thorium blanket to breed uranium-233. It is expected to be operational by 2010.
Fears that nuclear power programmes will be limited by shortages of fuel as well as claims that the construction and operation of a nuclear plant consumes more energy than it produces are so clearly without foundation that it is difficult to understand why they continue to be raised. But nothing changes, myths die hard. As Michael Barnes QC, the Hinkley Point inspector commented in his 1990 report: “ ...one of the most depressing aspects of the Hinkley Point inquiries was that when an issue of such momentous potential importance as global warming arose an obvious contribution to a solution to that problem, increased reliance on nuclear power, should be resisted as a matter of principle by organisations genuinely concerned with the environment.” (vol 3, chap 32.68).
Relative safety
The extreme measures taken to ensure the safety of nuclear power stations can be contrasted with the apparent lack of any real safety measures which might have prevented the recent fire at the Hemel Hempstead oil storage depot. By good fortune this fire occurred early on a morning when few people were around and the offices and other buildings close to the site were empty, otherwise the loss of life and injury would have ranked as a major national disaster. As it was the only loss was from the destruction of buildings and equipment.
As far as we can make out there were no vapour detectors which might have given warning of a build up of an explosive air/vapour mixture, and the tanks were only surrounded by concrete bunds to contain their contents but not spaced sufficiently far from one another to prevent damage from the domino effect of an explosion in any one of them.
A similar incident at the gas terminal importing gas by pipeline from Europe or at an LNG terminal would also lead to severe gas shortages.
Deceit
In an attempt to sway public opinion, opponents of nuclear power are claiming that the cost of decommissioning our nuclear power stations, put at over £50 or even £70 billion, makes nuclear power uneconomic. These figures are based on the £56 billion estimate of the Nuclear Decommissioning Agency for the cost of cleaning up all the “legacy” nuclear sites. The share of these costs allocated to the Magnox stations in the NDA figure is only £12.6 billion. The other ‘legacy’ costs include activities dating back some 50 or more years but do not include the civil stations operated by British Energy, and are far in excess of the much lower decommissioning costs expected for a modern water moderated reactor.
A blatant example is an article in the Independent by Andy McSmith, 3rd Jan, under the headline “Cost of cleaning up after nuclear power stations are closed down rises to £70 bn”. This claim, repeated in the first paragraph of the article, is then used as a lead-in to support an assertion by Michael Meacher that a new nuclear programme would be “financially insane”. Meacher’s assertion is repeated, highlighted in large black type in a separate box which dominates the whole article. The impression left on a casual reader scanning the headline, the opening paragraphs, and the unavoidable box is clearly intended to promote opposition to a new nuclear programme. This distortion might, just, be acceptable as a comment expressing McSmith’s personal opinion but it shows that reports in the Independent on nuclear power cannot be relied on for factual information; they will be doctored to support the paper’s pre-determined policy.
On the specific question of decommissioning the Magnox stations, while the NDA and the opponents of nuclear power emphasise the high decommissioning cost estimates, the valuable contribution to the UK economy of the 1,000 TWh or so of electricity these stations have generated over a 40 year operating life, estimated at £30 billion, is ignored by both.
In an earlier review, in 1994, (Nucl. Energy, 1994, 33, Aug, 223-228) the average Magnox decommissioning costs were put at £630 million, giving for 11 stations including Calder Hall and Chapel Cross, a total of almost £7 billion – about half of the present NDA figure.
It was estimated at that time this could have been funded by a relatively small charge of 0.12p/ kWh on the electricity they generated – sensible or ‘financially insane’?
Decommissioning costs
It is however legitimate to question the realism of the NDA figures which are based on the assumption of a total shut-down of all nuclear activity in the UK, restoring most of the present nuclear sites to a “greenfield” status.
But that the UK could now abandon nuclear power generation seems increasingly unlikely in the face of growing concerns over the security of our energy supplies and of global warming. The belief that world oil production is already at or nearing its peak is growing, and there are now real doubts about the wisdom of depending on Russia as a reliable supplier of gas at a time when UK dependence on gas imports is expected to increase substantially. Nor should we consider abandoning a reliable carbon dioxide-free electricity source at a time when the carbon dioxide concentrations in the atmosphere are relentlessly increasing. Similar concerns are echoed in other countries leading to an expectation of expansion of nuclear power output world-wide.
Over half the NDA cost estimate, £31.5 billion out of £55.8 billion is allocated to decommissioning Sellafield (in operation since the 1940s), to fulfill the green dream of turning Sellafield into a ‘Centre of Decommissioning Excellence’. The NDA assumption is that reprocessing in THORP will end in 2011, with MOX production ceasing in 2016. Yet if, as is sometimes claimed, a world expansion of nuclear power with an increasing demand for uranium leads to uranium shortages there will be an increased need to recycle and reprocess spent fuel. There will also be an increasing demand for MOX fuel to utilise the separated plutonium for electricity generation. Yet the NDA is seriously considering the option of “the export of plutonium for commercial use outside the UK” after MOX production in this country is abandoned – to reimport MOX fuel manufactured elsewhere? In addition the manufacture of conventional oxide fuel at BNFL’s Springfields site (£2.8 billion decommissioning cost) is seen as ending in 2022. The view of BNFL/ Westinghouse’s new owners after privatisation, on this is not considered.
Under its previous Secretary of State it seemed that the DTI policy was to distance the Government from any responsibility for, or association with, nuclear power whatever the cost; forcing British Energy to sell off at a knockdown price its valuable American and Canadian assets and, through the introduction of NETA, the new electricity trading arrangement, to bring about the downfall of British Energy, now crippled under the imposed restructuring agreement which channels 65 percent of its cash flow into the NDA; starting the privatisation of BNFL’s main profitable division, Westinghouse; and turning BNFL itself into a nuclear clean-up rather than a nuclear fuel supply company. Can it still be Government policy to plan for a complete withdrawal from all nuclear power activity at a time when world nuclear generation seems poised for a rapid expansion?
If, or rather perhaps when, a new nuclear programme is sanctioned in this country the new stations will be built, and possibly owned, by overseas companies – Westinghouse under its new owners building PWRs; new European PWRs for the French or German electricity companies which already have a dominating position in UK energy supply; or perhaps a Canadian heavy water reactor – in which case it would be the ultimate irony if Bruce Power were to take over British Energy.
The Independent again
Continuing with its biased commentaries on nuclear matters the Independent of 24th January featured on its front page under the huge caption – DANGER NUCLEAR WASTE – a wholly misleading and alarming account of the nuclear waste issue. This claimed that “Britain has 2.3 million cubic metres of nuclear waste stored around the country”. This figure while taken from the latest assessment of Nirex (19th Jan) hides the fact that almost 90 percent of this is classified as low level waste. Only 0.06%, 1,340 cubic metres, is high level waste, which we are told “could kill an adult within 2 minutes – and it remains lethal for one million years”. The improbable circumstances under which anyone could be exposed to this material are not considered.
The report goes on to claim that “It will cost £85 billion to bury all this radioactive rubbish.” Where this figure comes from is not revealed. Since everyone now seems to be waiting for CoRWM’s recommendations on how the waste should be disposed of the costs cannot yet be known.
But the 2.3 million cubic metres includes all the wastes accumulated over the past 50 or more years, including the military programme. It also takes into account the future expected waste arisings from the present nuclear power stations, with the last Magnox reactor closing in 2010, the AGRs up to 2023 and Sizewell B in 2035. The supposed £85 billion will then cover almost 100 years of nuclear waste production, during which time the nuclear power stations been an essential part of the UK electricity supply industry, meeting at the peak of production some 25% of total supply.
Rather than presenting nuclear waste as a source of concern, it should be recognised that it is only the nuclear industry where the problem of decommissioning disused plant and disposing of the wastes is being dealt with. It is not generally known that the oil and gas industries and above all coal generate larger quantities of radioactive waste at levels comparable to, or even above, some of the low level waste from the nuclear industry.
Reprocessing in Japan
Japan is now ready to start reprocessing at its large new plant at Rokkaho. They have taken their time about building this reprocessing plant but now Japan Nuclear Fuels Ltd plans to reprocess some 430 tonnes of actual spent nuclear fuel during a trial period of operation which will last until March 2007. They will produce about 2.3 tonnes of reactor grade plutonium which will eventually be made into mixed plutonium/uranium oxide (Mox) fuel for use in Japanese commercial light water reactors. A new fabrication plant for Mox fuel with a capacity of 130 te/yr is expected to be completed by 2011. Then Japan will have no need of all reprocessing work and Mox fabrication in plants in the UK, France and Belgium. This will be no great loss to France and Belgium because they have plenty of domestic demand for their capacity but in the UK it means the loss of a very valuable customer for British Nuclear Fuels plc and a serious threat to the plants at Sellafield.
It is remarkable that we have sat back and watched this happen. By the time we get round to building light water reactors capable of burning Mox fuel, as surely we must, we will probably have to go to Japan to get the reprocessing and fabrication work done.
EDF looking at UK and US
The French utility Electricite de France (EdF) is showing interest in the UK as well as the US markets for new nuclear power stations. The company, which is 85% owned by the French state, has an interest in Framtome’s latest reactor, the giant 1600 MWe European Pressurized Water Reactor (EPR), the first of which is being build in Finland and a second planned for Flamenville in France. The company is a member of the NuStart consortium which is seeking design certification of the US Nuclear Regulatory Commission but the interest in the UK market is a new – if obvious – development. Over the next twenty years Framatome ANP sees a world market for about 100 of its 1600 MWe EPRs.
The EPR is an ‘evolutionary’ design of reactor pushing safety to yet higher standards and retaining its competitiveness with its large size. Its main rival is the AP 1000 from Westinghouse which is a smaller 1000 MWe reactor of a ‘revolutionary’ design which achieves high safety with passive systems and economics by simplification of plant. In addition to these there is an evolutionary design – the Advanced Boiling Water Reactor – which is a third generation plant already operating in Japan and the Combustion Engineering 80+ design which is being built in South-East Asia. And don’t forget the latest design of Russian pressurized water reactor, the AES-91, the first of which has just started up at Jiansu in the Chinese province of Tianwan. So although we in the UK are now likely to have to import our next nuclear power station we do at least have a very good selection to choose from.
French keep going
The French not only have the largest nuclear power programme – producing 75% to 80% of electricity – and third generation reactors developed and ready to go, but they are still keeping the progress going. The French President has announced that the Atomic Energy Commission (CEA) is to start designing a prototype fourth generation reactor to start operation in 2020. This is some five years earlier than had previously been discussed. The CEA is expected to focus on fast reactors which will offer better use of uranium resources and reduced production of waste. In particular it will bring into use some 220 000 tonnes of depleted uranium which has been accumulated and stockpiled in the production of enriched uranium for present generations of reactors.
The CEA has abundant experience in the design and operation of sodium cooled fast reactors and can already consider going straight to a demonstration fourth generation plant. It also has early experience of gas cooled reactors and is believed to be considering substituting gas for sodium as an intermediate coolant but this would probably need the building of a prototype plant as a next step.
The current plans of the CEA call for about 40 million Euros per year to be spent on generation four research and development but future plans may call for a considerable increase and possibly the participation of international partners.
What price Russian gas
A dispute over gas pricing caused the Russian supplier, Gazprom, to cut off Ukraine recently. It was only a short interruption and was resolved when Ukraine agreed to eventually pay nearer the going European price of $230 per 1000 m3 rather than the low price of $30 which it had been paying. But it drew attention to the vulnerability of the rest of Europe to rows between different countries. At present western Europe – notably Germany, France, Italy and the UK – gets about a quarter of its gas from Russia and about 80% of that comes in pipelines that cross Ukraine. With North Sea reserves rapidly declining the vulnerability of the whole of Europe is now threatened. The answer is to stop burning it inefficiently to produce electricity and to use nuclear instead. But despite many earlier warnings we are likely to increase our use of gas before any new nuclear plant can come to our rescue. |
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Last Updated ( Tuesday, 07 February 2006 )
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