Guest post: Nuclear research and development, an industry perspective
Although the following article was originally written in 1992, we’re reproducing it here as it offers an interesting industry perspective on nuclear research and development. Thank you to Ken Teare for allowing us to use it for this week’s guest post.
Nuclear Research & Development – an Industry Perspective, K. R. Teare
This paper takes a personal view of the research and development needs of the nuclear industry in the UK, makes comments on the most relevant sources of funding for such R & D, and also points out some areas of R & D which appear to me to be not relevant.
These views are based on over 30 years in design, operation, and maintenance of PWRs for nuclear propulsion. This has led to a certain detachment from the mainstream of the industry, and has given me the opportunity to take an independent view. I start from the premise that the world’s population will continue to increase; that the less developed nations will increasingly demand the same standards of living achieved by the industrialised nations; and that there will be rapidly increasing concern about the depletion of non-renewable resources, and the environmental damage of exploiting them, particularly of burning fossil fuels.
This will eventually lead to a general realisation of the benefits of safe, economical, nuclear power. However, we must remember the crucial importance of safety and economy. Moreover, we must not let mistaken policies today kill the industry before the eventual opportunity comes about.
The following is little more than a list of topics which should be given more emphasis by industry (both the Electricity Supply Industry and the vendors) and Universities as appropriate. They range from basic research and feasibility studies to the development of products and services. In principle, the source of funding, and the location of the work, should move from a bias towards Government and Universities at the research end of the range, to industry at the product development end, and I see no fundamental disagreement here, except for an apparent reluctance on the part of the Government to spend any money at all on some of these topics.
I have subdivided the field somewhat arbitrarily into the following topics: Operations and Maintenance, Technology, Health Effects, Reactor Design.
Operations and maintenance
We already have a great many reactors operating world-wide, and whatever the anti-lobby may wish, they will continue to require network systems to aid interpretation. The accident management team also requires much better systems to predict the outcome of actions they are considering, both in-plant and off-site, much faster than real-time.
The field of thermal/hydraulics, particularly in two-phase flow, is still rich with uncertainties, and its analysis is still as much an art as a science. In particular, there is need for more experimental validation of the theory in Loss of Coolant Accident (LOCA) situations, and the effects of voidage, stratification, flow reversals and Emergency Core Cooling System (ECCS) injection.
We must be able to demonstrate the effectiveness of protection against LOCAs, with confidence, but without excessive pessimism. Present reactors are probably much more capable of counteracting LOCAs than present licensing calculations would indicate.
We must learn to do, and gain acceptance for, best estimate calculations and their associated uncertainties. I believe our inability to do this is a major source of unnecessary pessimism common to both deterministic and PRA studies. Among the most intractable problems facing those striving to maintain reactors in service are materials which have proven to be susceptible to radiation damage or to environmentally assisted cracking ( EAC) . Research and development into materials which are inherently less susceptible to these failure mechanisms would be of great value in the future. More detailed modelling of these failure mechanisms (particularly EAC) may lead to palliative or corrective measures of value in the short term. Studies should be undertaken into generic areas of weakness in the design, materials, or operation of components and systems.
I do not believe we have taken enough time off to assess what might be the next major problem. We have had SG tube failures, RPV irradiation embrittlement, stress corrosion cracking – what is coming next? Whatever it turns out to be, I would suqqest the evidence already exists to warn us, only we haven’t spotted it. Picking it up early may enable us to minimise the consequences.
Decommissioning and waste disposal are important topics, already receiving a great deal of attention. I would make one suggestion for further work. This is the necessary R&D to justify use of the reactor site as the ultimate storage facility for all its own radwaste, apart from irradiated fuel. In the case of the SIR reactor, this seems a viable prospect technically, although I suspect outside the present rules.
Clearly, the improved operation main source of existing of funding for reactors should work aimed at be the nuclear 29 utilities, or vendors who think they have perceived a potentially profitable product or service.
Finally, under the heading of technology, I suggest that the future prospects of the nuclear industry would be enhanced if an economical way could be found to use fission energy to generate an easily transportable fuel. Hydrogen from the electrolysis of water has been suggested, and indeed has its attractions: it also has disadvantages. I would like to see research into the synthesis of fuels such as methanol from water and carbon dioxide, making use of fission energy effectively storing fission energy in a form suitable for transportation, or for remote sites, and with a nett zero emission of CO2.
In relation to the detriment caused to the human race, more is known about the impact of ionising radiation than virtually anything else. There is little case for further research in this area, other than that required to allay public concern over leukaemia. My concern is that the public have such a grossly distorted view of the risks of radiation, when compared with all the other potential causes of ill-health or death posed by our natural environment and lifestyle. This remains a major block to the development of our industry.
We therefore need to establish more clearly the facts (or best independent professional judgements) about the comparative risks of nuclear energy production and other activities. Only then can we make a serious start to influencing public opinion. However, this can only be done outside the nuclear industry. No matter how accurate and sincere, any information emanating from the British Nuclear Forum will be regarded by the sceptic as tainted at best. Furthermore, merely presenting the facts will do little to influence public attitudes. We must commission research, perhaps in a University psychology department, into why the public attitudes are in such conflict with the facts (or at least our interpretation of the evidence). Only when we understand this do we stand any real chance of changing these attitudes.
We should enlist other users of radiation, such as hospitals, research establishments, and the general engineering industry to share ownership of this problem, and assist in its resolution. I think Government funding is entirely appropriate for these activities, if only to restrain accusations of bias on the part of the nuclear industry.
The crucial need in reactor design is to develop, and go on to build and operate, designs which at least match present systems with respect to safety and costs, but which are much more tolerant of faults and operating errors. The aim, to be approached as closely as reasonably possible, is that safety must become self-evidently present, based on natural processes, not dependent on ever more complex, diverse, redundant safety systems, and a near superhuman standard of operation and maintenance.
Indeed, for nuclear technology to be operated satisfactorily in less-developed nations, it must be made less dependent on extremely high standards of supporting technology for such standards will not be reached in these countries on the timescales by which major generating capacity will be demanded. Evolutionary reactor developments are an important move in this direction. However, I believe we must go much further into the passively, or self-evidently safe reactor concepts. It seems most probable that any such passively safe systems will be based on Light Water Reactor (LWR) technology, in view of the investment already made in the development of LWRs, and the considerable success demonstrated by thousands of reactor years of safe and economical operation.
We must not, however, totally ignore the possibility of other technologies – there may well be considerable potential for passively safe fast breeder reactors, or high temperature gas-cooled reactors, for example, and I would welcome research into such concepts. There are several other themes to explore in directing the future policies in reactor design. In the short term, there are concerns about the proliferation of weapons grade material – one might in a way welcome the growth of this problem insofar as it is due to existing weapons being withdrawn from service and dismantled. Clearly the best way to get rid of this material, both high enrichment uranium and plutonium, is to burn it in reactors, and get useful energy out of it. We already have the means to do this, by mixed oxide fuels in LWRs, or by the adoption of Fast Breeder Reactors (FBRs), but in the UK at least we lack Government commitment to FBRs in particular.
This is hard to understand. It is a proven technology, with costs that are reasonably accurately known, and which will become both economic and essential in the foreseeable future. Yet, the present Government seems to believe that the technology can be left on the shelf for a few decades, then resuscitated. This is mistaken. Technology resides more in the minds of the technologists than in reports in the library. It dies with the technologists, if a new generation is not bringing it on. It becomes superseded if others continue developing the technology. Present Government policy will lead, in a few years time, to the situation where we will have to buy from other nations the technology we have done so much to create – with our vendors struggling to pick up whatever crumbs they can from under the table.
If the potential for proliferation remains of concern to society, then there are possible systems which have been suggested for countering the threat, including novel thorium burners, which do not involve reprocessing, and which never create weapons grade material. There is also scope ·to develop sabotage – and tamper-proof systems, to guard against wilful generation of risk to employees and public.
There are clearly many reactor design issues which could, and in my view should, be explored. Who should do the work? How should it be funded? One view is that industry stands to profit from it in the long run, therefore industry should be prepared to invest now. This seems to me to defy the real world. The vendors are frequently overlooked as part of the industry. These are the organisations which enrich the community by making products and selling them world-wide. They have the capability to carry out major feasibility, design and development studies. However, they lack the financial resources to invest hundreds of millions of pounds in new developments particularly in competition with overseas companies which do receive support of this order from their respective Governments.
The supply industry can hardly be expected to make a major commitment. They have been set the objective to demonstrate profitability in the short term. The non-nuclear part will continue to burn coal and gas as long as it appears the cheapest and easiest way ahead who can blame them. Nuclear Electric and Scottish Nuclear will have to concentrate on operating efficiency in their current plants (including Sizewell B in a few years time). The City will not invest in such long-term activities. It sees sufficient opportunities for other profitable investments bringing quicker and more certain returns. The only sensible option is Governmental support. Since this is ultimately a global problem of providing energy to an ever more demanding, ever growing world population, with minimum adverse consequences on the environment and scarce resources, all the world’s Governments must combine to tackle this problem.
How unfortunate, then, that our Government appears to backing out of one international project (the European Fast Breeder) and is apparently making no effort at all in other areas, such as LWR developments. This lack of vision must be a desperate concern. Global problems require global cooperation for their solution.
Do the Universities have a role? Yes. At the conceptual and feasibility study end of the scale the Universities have a vital task to introduce novel concepts, and provide independence from “The way we have always done it”. Funding at this level really should not be a problem – industry and Government should combine to support projects of the type I indicated earlier.
Areas Where Further R&D Is Not Warranted
In drawing your attention to some areas where I believe more emphasis is required in R&D, I have only covered part of the story. I also believe there are several R&D topics which are not appropriate, and where present funding could be redirected to the overall benefit of the industry.
I have mixed feelings about my first suggestion – reactor physics and shielding methods, since it was my own specialisation for many years. I think we have now reached the point where a combination of the ingenious approximations forced on us by earlier generations of computers, and the raw power of modern workstations, means that we can compute most situations to adequate accuracy. In core performance, for example, there are far greater uncertainties in the heat transfer and fluid flow than in fission power distributions.
Secondly, I suggest that the industry world-wide has gone way over the top in its attempts to analyse the most severe accidents, such as core melt. An analogy would be Boeing trying to analyse in detail the processes of deformation in a 747 as it flies into a mountain. Quite rightly, the aviation industry concentrates its efforts in preventing/the impact rather than analysing it. This, of course, is because an aircraft hardened to be capable withstanding the impact would never get off the ground. In the nuclear industry we have no such obvious logic driving us, and we have tried to demonstrate that the features we incorporate into our plants to mitigate these severe accidents will work, and so justifying our taking credit for them. I think that this has led to non-optimal designs. I would prefer us to concentrate our efforts on features to reduce to an acceptable level the probability of accidents progressing to that state, and then justifying those features. Any additions thereafter to mitigate the severe accidents should be incorporated to the extent that is sound engineering to do so, detailed justification of them being unnecessary.
Finally, I would offer the opinion that while the fusion programme is a remarkable demonstration of man’s capability in intellectual and engineering terms, it is a totally misguided effort. To paraphrase the logic as I see it, the original intent was to cope with the eventual shortage of fossil and fissile fuels by the use of abundant materials – seawater and lithium. Because the fuel would be abundant, it would be cheap. This is probably true. Because the fuel would be cheap, the power would be cheap. This does not follow. The capital costs of fusion power will be very high – witness the complexity and cost of JET, which is only a low power experimental facility, capable of producing a few megawatts against the gigawatts of a commercial plant. Moreover, fusion plants will be expensive to operate. At least with present technology, and in my view this is a fundamental problem not amenable to solution, the first wall will suffer such irradiation damage that it will require frequent maintenance. This will be in a high radiation environment demanding remote operations. This can no doubt be done, but at a cost, not least in the capacity factor of the plant an important component of cost of electricity, particularly in a high capital cost plant. Compare the fast reactor and fusion programmes. The fast reactor is proven technology, with commercial designs being developed.
An orderly continuation of the present programme will provide a means of exploiting an existing fuel reserve sufficient for some centuries, at costs which are predictable, and which will soon become competitive. Fusion technology is unproven, would take many years to develop and prove, at great cost, with no certainty of success. Even if it does succeed, there are good reasons to believe it could not be economic. It is exciting technology but it defies common sense, and is fated to become a commercial disaster. We should be spending our scarce resources on advanced fission systems, such as FBRs and passively safe reactors.
Much of the R&D work I am advocating could be carried out by industry, but there are many areas where higher education institutions (HEIs) can participate, supported by both industry and government as appropriate.
I look to the HEIs to identify areas where they believe they have the capability to contribute. A number of the topics I have mentioned would require a change in licensing attitudes before they could be implemented as design or operational practices. I am hopeful that over a period of time, the licensing authorities will show a flexibility towards details which are entirely compatible with public and employee safety, but are outside present rules and practices. Licensing authorities should set the high level objectives which must be met.
It should be up to the designer to decide how this should be achieved, and to demonstrate compliance. Lower level rules, case law, customary practice, are useful guidelines, but must not be allowed to foreclose the options open to the designer. I have identified a list of R&D topics which I consider are worthy of more intensive effort than they currently receive. Many of these should be funded by the nuclear utilities or vendors, since they should see short-term benefits. However, I believe Government policy is seriously flawed in respect of the longer term. The choice of projects to support, and conversely, those not to support, is totally misguided. Worst of all, the lack of a global approach to global problems on the part of not only the UK Governent, but all Governments, should be a concern to us all.