By Dave Elliott
I have been looking at some early, novel, nuclear ideas and how some of them are being re-explored. Thorium, molten salt reactors, high temperature reactors, fast neutron reactors- they have all been tried earlier on, with mixed results. In a new book for IOPP I ask, will the revamped variants, including smaller versions, do any better? And more radically, do we actually need any of them- has nuclear really got a future?
By Dave Elliott
Nuclear power generation technologies are now cost competitive in some contexts and innovation is gathering pace across the sector, British consultancy Lloyd’s Register says in a report Technology Radar – a Nuclear Perspective. A parallel, wider Technology Radar – Low Carbon report, reviews renewables, energy storage and infrastructure, as well as nuclear. That is quite positive about solar power and storage, but it also presents nuclear as a possible winner. (more…)
A new year’s worry…
By Dave Elliott
One clear difference between renewables and nuclear power is that the former do not lead to the production of long-lived radioactive wastes and the associated problems and costs of dealing with them. Also, old wind and solar facilities can be easily removed, whereas nuclear plant decommissioning is complicated, risky and expensive. With a new UK nuclear expansion programme planned, how much will it cost us to eventually clean it up and deal with its wastes? (more…)
By Dave Elliott
In a post-Xmas pre-new year Scrooge-type austerity mood, I worry about the money we are wasting on energy. If you look at Sankey diagrams of energy flows from primary resources to final end use, you will see that for many countries around half the raw energy input is wasted in the conversion process, most of it being rejected into the atmosphere as heat, for example from steam-based fossil and nuclear generation systems.
The nuclear industry does seem to be having bad luck. Its flagship new projects, the European Pressurized water Reactors (EPRs) being built in Finland and France, are both well behind schedule and seriously over-budget, with a range of construction problems and errors pushing up costs and putting completion years away. For example the estimated final costs for Olkiluoto 3 in Finland have risen from €3 bn to €4.5 bn and the completion date has been put back from 2009 to 2012. The second plant, at Flamanville in France, is already 9 months behind schedule, and is not now expected to begin operation until 2013, rather than 2012 as originally hoped. The cost of the power produced by it will be around 20% more than planned – around €55/MWh instead of the €46 announced when the project was launched in May 2006.
Certainly a surprising number of a safety issues have emerged during construction; evidently more than 3,000 mistakes have made by the builders so far at Olkiluoto. See the quite striking poster summary from Greenpeace at www.greenpeace.org/raw/content/finland/fi/dokumentit/ol3SafetyPoster.pdf
Some of this might be put down to teething problems with “first of a kind” plants. But perhaps more fundamentally for the future, UK, Finnish and French nuclear-safety regulators have objected to aspects of the EPR design: “The EPR design, as originally proposed by the licensees and the manufacturer, Areva, doesn’t comply with the independence principle, as there is a high degree of complex interconnectivity between the control and safety systems.”
As World Nuclear News noted, some safety systems protect against the failure of control systems and so should be impossible for them to fail together, which means Areva must re-work the design if it is to get regulatory clearance – and before construction of EPRs in the UK.
Meanwhile the US nuclear regulator has objected to a key part of the Westinghouse AP1000 design: it said that it would have to be modified to receive approval for use in the US.
The AP1000 is another candidate for UK deployment.
The UK Health & Safety Executive is looking at both the EPR and AP1000 designs, and, according to media reports had identified possible problems which, if not progressed satisfactorily, would mean that H&SE “would not issue a design acceptance confirmation”.
H&SE however pointed out that they were only part way through their assessment and that there were confident that any issues would be resolved.
Some politicians also seem confident about the merits and viability of a major new nuclear programme. Gordon Brown told the CBI that “we will now build not 12 gigawatts of nuclear capacity but 16 gigawatts, a total for new building that is bigger than all our current nuclear capacity”. But with possible technical problems still unresolved, and with delays mounting, the prognosis for rapid deployment does not look too good.
The financing issues are also looking difficult. Although the UK government have insisted they will not subside the nuclear programme directly, the City Group economic consultants have concluded that nuclear can’t be financed just by private sector: www.citigroupgeo.com/pdf/SEU27102.pdf. In fact, although no direct financial support is being given, a range of indirect subsidies are in train. For example, government seems to be accepting to need to support a “floor price” for carbon in the EU Carbon Trading System of around £30/tonne, which would help make nuclear more economic, but would load consumers up with extra costs. The Times talked about an extra £227 on annual energy bills, although EDF put it lower. Even so, it’s likely to be politically difficult.
And more problems are looming. Plans for long-term nuclear waste disposal could come unstuck because of new evidence of corrosion in copper, a material that was to be used to seal waste underground. Examination of copper artefacts from the Vasa, a 15th-century galleon raised from Stockholm harbour, has shown a level of decay challenging the scientific wisdom that copper corrodes only when exposed to air.
The waste issue is likely to be made even tougher since, to improve their economics, the new nuclear plants proposed for the UK will have high fuel “burn-up”. This means that the fuel is enriched to a higher level and stays in the reactor longer, with more of the fuel being converted to plutonium and other radioactive by-products of fission. This in turn means that the spent fuel is hotter and more radioactive- which could present problems with plant operation, waste management, storage and disposal. Especially since, given that there are no plans for reprocessing, it will have to be kept on site at the nuclear plant for many decades (EDF has just suggested 60 years for the proposed new plant at Sizewell) before it goes off somewhere (as yet undetermined) to be kept isolated for 100,000 years or so.
All this makes it rather hard to accept the governments claim, in its recent the National Policy Statement (NPS) on nuclear, that it is “satisfied that effective arrangements will exist to manage and dispose of the waste that will be produced from new nuclear power stations” and that “as a result the IPC [Infrastructure Planning Commission] need not consider this question” when reviewing the plant planning applications.
This has drawn a lot flack. Four former members of CoRWM, the UK government’s first advisory committee on radioactive-waste management, including its chair Prof. Gordon Mackerron, noted that their 2006 report had only looked at “legacy” waste – the new wastes opened up new issues: “In the absence of a process or acceptable policy for new build wastes, they may remain on site indefinitely. It is quite possible that, as a result of sea level changes, storm surge and coastal processes, conditions at some of the most vulnerable coastal sites will deteriorate thereby making it increasingly difficult to manage the wastes safely. The problems presented by managing wastes in the very long-term will be both generic and site-specific. Consequently we find it hard to understand why the IPC, when considering applications for the development of individual sites, need not consider the question of waste management. Given the levels of public anxiety raised by the issue of nuclear waste and the burdens of risk and management that are imposed on future generations we believe consideration of safe management of wastes at each site should be a primary concern of the IPC.”
The NPS is a consultative draft. Whether the suggested block on discussion of waste by IPC will survive remains to be seen.
The government’s new draft National Policy Statement on nuclear power, indicating
which issues the new Infrastructure Planning Commission (IPC) should take on
board, and which it can ignore, contains this remarkable statement:
“The Government is satisfied that effective arrangements will exist to manage and
dispose of the waste that will be produced from new nuclear power stations. As
a result the IPC need not consider this question.” The draft statement
goes on to say that: “Geological disposal will be preceded by safe and secure interim storage.”
So it seems, the waste issue is all in hand and we needn’t bother too much about it, or any problems with the much
more active spent fuel that the new reactors’ high-fuel “burn-up” approach will
create. Despite the fact that the highly active spent fuel is to be kept on
site at the plant for perhaps several decades, that is evidently not something
IPC will have to consider in its assessment of whether the proposed plants can
go ahead. Instead the IPC will just focus on any conventional local planning
and environmental impact issues that may emerge in relation to the 10 new
nuclear plants that the government has now backed.
apart from the issue of on-site spent fuel storage, there are plenty of other
issues to discuss. For example, the risk of flooding in the years ahead, as
climate change begins to bite. Dungeness was dropped off the original 11 strong list, due to local
eco-issues, including, we hear, concerns about flood risks. That leaves the
following, all of them also coastal sites, although allegedly less at risk: Bradwell,
Hartlepool, Heysham, Hinkley Point, Oldbury, Sellafield, Sizewell and Wylfa,
all existing sites, plus newcomers Braystones, and Kirksanton, both in
last one is currently the site of a 3.5 MW windfarm, partly local community
owned, which would have to be dismantled. It’s one of the more successful UK
wind farms. Will, I wonder, the
IPC treat its potential very symbolic demise as a negative environmental
more relevantly, will the IPC safeguard local interests effectively? IPC chair
Sir Michael Pitt says that the large nuclear and other projects it will look at will
“raise important issues for the nation and for local communities and we want
the public to have confidence that their views will be heard. In every case there will be an
opportunity for an open floor hearing as part of the IPC examination process”.
green groups see the whole thing as top down, autocratic and designed to
steam-roller through unpopular plans rapidly. CANE, Communities against Nuclear
Expansion, said: “At a time when public confidence in our political process is
at an all time low, government have decided to take to themselves more power to
override people’s wishes.” But Sir Michael said: “The bottom line is that the
IPC will not accept any application, where it considers that the consultation
process has been unsatisfactory or the community’s concerns have not been
of the Earth (FoE) nevertheless remains concerned: “The IPC is an unelected,
undemocratic body – the new Commissioners aren’t directly accountable to the
people their decisions will affect. It’s going to be very difficult for local
people to get their voices heard, especially with key documents being so
technical and opportunities to attend inquiries so few. If people are unhappy
with the process they’ll have to take the matter to court, which is extremely
difficult and costly.”
FoE and other green groups have said that, although they can see that the new
planning system might in theory over-ride local opposition to wind projects,
they are not willing to compromise basic democratic principles. Tony Juniper,
then FoE’s director, noted a while back: “Government
advisors tried to sell the planning reforms to green groups on the grounds that
we would get our wind power more quickly. We rejected that offer and instead
said that we would prefer to win the arguments through debate, not via a lurch
toward centralised planning.”
reality though it could be that trying to bulldozer projects through, using
what might be seen as draconian measures aimed at defecting opposition, could
be counter-productive – consolidating opposition. This could well also prove to
be the case for nuclear plants, which, unlike wind farms, most green groups
oppose. Maybe, in that case at least, perversely, IPC will thus do opponents of
nuclear power a favour.
Dealing with nuclear waste has proved to be the Achilles heal of the nuclear fuel cycle. Although there are plans, no one has yet established a full-scale long-term repository for high-level waste. However, enthusiasts for reprocessing spent nuclear fuel have claimed that, as well as producing more fuel, this is a way to reduce the amount of high level wastes.
That’s true up to a point, in that reprocessing basically is about extracting the plutonium and also left over uranium- so what’s left is lower or medium grade waste. But that doesn’t change the total amount of radioactive material. Indeed the chemical separation process used for plants like THORP at Sellafied leads to a lot of secondary activated materials- more low and medium grade wastes to deal with. And the separation process is complex, expensive and a major source of radiation exposure risk problems for both workers and the public e.g. most of the accidental leaks and also allowed emissions from the nuclear cycle have come for reprocessing plants. It’s been estimated that nearly 80% of the collective occupational radiation dose associated with the complete nuclear fuel cycle comes from reprocessing activities, measured on the basis of the dose per kWh of power finally generated.
The UK government has decided that fuel from any new reactors built here should not be reprocessed. It is cheaper and easier to dry store the spent fuel. Quite apart from the cost, that’s not a surprising decision given that THORP has been out of action since an internal leak in 2005- it’s not clear if it will ever reopen fully before it’s due for final decommissioning. Moreover, we don’t now need plutonium for weapons (we have enough) or to fuel Fast breeder reactors- the UK Fast Breeder programme at Dounreay was closed a decade or so ago. Some of the existing stock of plutonium has been turned into a new fuel, mixed with uranium oxide, called MOX, but the plant for making this has also had problems and may soon be abandoned.
The UK and France have been the only countries with major reprocesssing plants- they have reprocessed fuel for other countries. The US backed away from reprocessing in the 1970’s- there were worries about the cost and about the risk of illegal diversion of plutonium. But President (W) Bush reinstated the idea- as part of a major US led global nuclear push, the Global Nuclear Energy Partnership (GNEP). One version of the idea was that the USA would supply small sealed nuclear plants (e.g. mini nukes of the sort being developed for remote sites) to client states around the world, focussing on developing countries, the spent fuel from which would be brought back to the US for reprocessing- to extract the plutonium and uranium. This material could then be used in a new fleet of US nuclear plants, including possibly fast breeder reactors. The claim was that this would be a closed fuel cycle, controlled by the US, with no (or less) risk of proliferation/diversion.
Enthusiasts talked up the role that could be played by the proposed Integral Fast Reactor (IFR) linked in with on-site pyroprocessing to recycle spent fuel. That approach is claimed to produce much less secondary waste than conventional chemical PUREX reprocessing. And it was claimed that some wastes could actually be burnt up in the reactor itself.
However, President Obama seems much less enamoured of the nuclear option. While not opposed to it, his pre-election New Agenda web site said ‘Before an expansion of nuclear power is considered, key issues must be addressed including: security of nuclear fuel and waste, waste storage, and proliferation’.
And in office he withdrew $50billion in loan guarantees for new nuclear plants that had been expected to be included in the US Economic Stimulus funding, and also halted work on the proposed nuclear waste repository at Yukka Mountain in Nevada. It was expected to cost $96.2 bn. About $13.5 bn has already been spent on it. Other sites may now be looked at.
Most recently the US Dept of Energy cut its assessment work on the US part of the Global Nuclear Energy Partnership programme, since, as the World Nuclear News services put it, the US ‘ is no longer pursuing domestic commercial reprocessing, which was the primary focus of the prior administration’s domestic GNEP program’. It added that ‘As yet, DoE has no specific proposed actions for the international component of the GNEP program’.
25 countries had joined the GNEP, but the US was the leader, so it’s unclear what will happen to it – and to reprocessing. Japan has been trying to develop its own reprocessing capacity, but at $20 billion, it’s proved to about three times more expensive than originally budgeted. And as the world’s only non-nuclear weapons state operating such a facility, the project attracted substantial national and international opposition. Overall, while it’s certainly not yet abandoned everywhere, it does seem clear that reprocessing is increasingly falling out of favour around the world- except perhaps in countries seeking a way to make bombs!
While biofilms can corrode metals and speed up rock dissolution, it looks like the assemblies of bacteria could actually help to protect nuclear waste. Jean-Louis Crovisier of the Centre National de Recherche in Strasbourg, France, has found that A. Thiobacillus thiooxidans bacteria can reduce the amount of elements such as strontium and caesium dissolving from nuclear glass into a solution of water in the laboratory.
Speaking at the EGU meeting, Crovisier explained that scientists who believe biofilms damage glass and concrete-based materials are finding bacteria or biofilms in holes and assuming that they have caused the hole. He reckons that’s equivalent to finding early humans living in caves and deducing that they made the cave.
The real test, according to Crovisier, is comparing changes in materials in the presence and absence of bacteria. He has found that both Pseudonomas bacteria and A. Thiobacillus thiooxidans lowered the concentration of caesium and strontium entering water from a nuclear glass, compared to sterile conditions. This indicates that the presence of a biofilm is actually protective, potentially trapping the elements.
As to whether biofilms could be used to protect nuclear waste in the field – it’s still early days. Research so far has only taken place in the laboratory and much more is needed before any application – for example, scientists would need to find out the effects of a consortium of bacteria rather than just one species at a time. The species making up a biofilm would also be likely to change over the hundreds of years that the waste remains radioactive.