Nature Materials 7, 686 - 687 (2008)

Nuclear energy — safe and secure?

The present revival in nuclear technology is prompting concerns about its safe use. Nature Materials talks to Tomihiro Taniguchi, Deputy Director General at the International Atomic Energy Agency, responsible for nuclear safety and security.
Introduction

What prompted you to take up your present position?
Nuclear energy |[mdash]| safe and secure?

IAEA

I was asked by the Japanese government whether I would be interested in this position. I worked for more than 30 years in the Japanese government, in METI [Ministry of Economy, Trade and Industry], mostly in the areas of science, technology, industry as well as energy. I was also the vice-chair of the IPCC [Intergovernmental Panel on Climate Change], and contributed to their third assessment report. The IAEA is a very interesting place to contribute to global issues, particularly solutions for major challenges of energy and environment through advanced technology.

What are your responsibilities at the IAEA?

I am responsible for nuclear safety and security. When I came here in the summer of 2001 I was only responsible for nuclear safety, but right after the September 11 events, security became an additional, very heavy responsibility. For both safety and security, the major objectives are to prevent a severe nuclear accident such as Chernobyl, and to prevent terrorist attacks on nuclear facilities and malicious use of nuclear technology. At the same time the capacity to respond to such accidents and events is important for controlling and mitigating their impact, including the social impact. For these purposes the agency has established safety standards and security guidance documents as well as many safety and security review and advisory services on the application of these standards. In parallel, as a consequence of Chernobyl, an international framework of legally binding agreements was developed and implemented through the 1990s and early 2000s.

Is it difficult to implement good safety standards amongst your member states?

When I arrived here the nuclear world was relatively quiet. Recently, energy supply security issues, discussions on global warming, rising oil prices, and as a consequence the revival of nuclear energy are receiving a lot of attention. As this revival is rapidly developing on a global scale, there is a need for common safety standards and their application. During the seven years I have been with the IAEA we have achieved very significant improvements both in the content of the standards as well as their application. For instance, when I arrived there were long discussions in the European Union about developing European standards, but eventually they were convinced that it is much better to use the IAEA ones. Also, countries that use our assistance are obliged to use our standards, and suppliers and vendors of nuclear technology know this. Before I arrived here, the agency standards were regarded to be of secondary relevance and mainly for use by developing countries. But the situation is rapidly changing towards the global application of IAEA standards, and new nuclear plants almost everywhere refer to them.

How do you develop and control the application of IAEA standards?

It is a very open, transparent process that we established in recent years. For safety standards there is a commission at the top, and there are four committees in each major area related to nuclear and radiation safety. These committees are fully open to any member country as long as their representatives are technically well-qualified. We have a four-month period of consultation by the member states, so all can comment and request modifications and revisions of the standards. This collaborative effort is one of the reasons I feel that our standards are systematically and continuously improving. An effective implementation of IAEA standards is essential for ensuring a high level of safety. The IAEA provides safety services and appraisals of the implementation of the standards at the request of member states. Lessons learned from these applications are actively used as feedback for revision of the standards.

How about nuclear security?

This is a more complex area, because safety is primarily a science-based area, where we can maintain this open and transparent approach. But in the security areas it involves more sensitive and confidential information, which includes discussions with intelligence agencies, law enforcement and border control, all of which maintain a culture of confidentiality to protect information in the best interests of security. The challenge in this area is to strike a balance between the need to protect information from those that wish to do us harm and the need to be open and transparent in our security activities. Furthermore, human skills and experiences, rather than scientific expertise, are important in many areas of nuclear security.

You also deal with possible aftermaths of accidents.

Fortunately, as the result of significant improvements in nuclear safety, there have not been any large-scale accidents since Chernobyl. Of course national efforts are important, but they need to be complemented by international efforts. In the area of radiation safety there have been many smaller incidents where we have been helping the member states to better respond and mitigate these. And in this sense our Incident and Emergency Centre (IEC) stands ready to effectively respond to events 24/7. Although fortunately there haven't been any serious accidents, we have been developing effective response capabilities worldwide. But the agency's major task is not controlling and managing accidents; this is the responsibility of the user and the national government. The agency's major function is to help the member states to better prepare and respond to such emergencies. After Chernobyl, there were international legally binding agreements, and several important conventions. As for improvements, with the support of the IAEA, the nuclear community has shared much knowledge and many lessons that have been learned following events. In addition, the IEC routinely conducts exercises to test national and international response programmes worldwide. I think sharing of information is getting increasingly important both for countries with new nuclear programmes as well as countries with mature programmes whose facilities are ageing.

What kinds of areas are important for the safety of new generations of nuclear reactors?

The planning and construction of a new plant are based on proven and demonstrated types rather than new generations of reactors. For the so-called generation IV reactors, intensive discussions are taking place but I feel it will take time until this generation of reactors will be introduced to the market. Because of such strong safety concerns, the introduction of new, innovative designs is rather slow. In the past, there have been very limited innovations, but as the market revitalizes there will be much more activity in R&D. For instance, there are industry activities to develop small, standardized reactors. Another area is intrinsically safe designs where even the loss of coolant in the reactor would not lead to radioactive releases, although the fully passive, intrinsically safe reactor is still in the process of development. Of course, such developments need to be combined with security, safeguards, minimization of radioactive waste during operation as well as the capability for practical decommissioning. All these features need to be combined with feasible economics of course.

How difficult is it for a new country to get into nuclear energy?

Actually, the challenge is again safety and security. Commercial vendors can readily supply the technology and fuels, as well as training and technology transfer. However, safety and security is clearly the responsibility of the operator and the government of the country that is to receive these facilities. I am concerned about the optimism and complacency of some of the countries who have very limited expertise and safety infrastructures, and tend to think that money can buy everything. But safety and security can not be imported or outsourced. Once they actually start building up their infrastructure and technical expertise, then they begin to understand the magnitude and duration of the challenge of nuclear safety and security. Capacity and knowledge management more generally will be a key component of nuclear safety and security. In order to prevent another serious accident, we need new thinking and a new approach adapted to the global information age. This is why I prefer to use the phrase vitae nova rather than renaissance in conjunction with the new interest in nuclear energy. What we need are fresh insights, an overcoming of old mindsets and the promotion of a modest but careful consideration.

Are we educating enough nuclear engineers?

No, and this is a challenge for new countries in particular, although it can be difficult even for countries with mature programmes who are now embarking on a relatively ambitious nuclear development — the UK is a typical example. It is difficult to quickly recruit and build up the necessary technical expertise, particularly for the regulatory side. The industry can recruit competitively with higher salaries and better benefits, whereas the governments tend to be left behind in the revitalized labour market. A big issue in the education of engineers is also the scepticism regarding science and technology, as particularly seen by the declining interest in engineering amongst the younger generations.

How will the share of nuclear energy in the primary energy supply develop in future?

The share of nuclear energy cannot increase much further because the overall energy demand and consumption is growing very fast. As the supply of oil and gas tapers off, most of this gap will be closed by coal. Nuclear energy, and to some degree renewables, are only supplementary to this development. In my opinion, we should be focusing very much on increasing efficiencies — not only the efficiency of our use of energy but also the efficiency and cleanliness of using coal. Achieving clean and efficient coal is a real challenge, particularly for developing countries. If you look at China and India, future power plants are predominantly coal. Even if things go well in developing nuclear energy, the nuclear share in overall primary energy is 6–7%, and within the electricity and power supplies maybe 16–17%, at most 20%, depending on the timelines. The remaining part needed to replace oil and gas will have to come both from higher efficiency and from coal. Replacing the current 400 nuclear power plants is a big challenge, and to build many more reactors beyond that in a safe and secure manner would be an even bigger challenge. Extending the lifetime of present power plants would of course be a very cost-effective way, because the machines are very robust, but we need to carefully assess how to manage the ageing process.

To keep the nuclear option open, we also need to recycle nuclear fuel.

The long-term supply of nuclear fuel is clearly a problem if we rely only on uranium. But if we recycle fuel and use plutonium, we have enough resources for over a century. Also, thorium resources are estimated to be greater than uranium resources. However, the benefits of fast reactors cannot be enjoyed unless we establish an economical fuel cycle and recycle. But we should be aware that recycling fuel for fast reactors is more complicated than for the present light-water reactors. To make use of thorium also requires conversion. For the development and deployment of recycling technologies, suitable safeguarding and storage of the recycled fuel becomes important as this fuel is much more radioactive and with higher proliferation risks. Therefore, recycling facilities should be limited in numbers and should basically be managed as multinational facilities.

Does safe long-term storage exist?

In my opinion the lack of long-term storage facilities becomes an issue only if we adopt recycling options. For the moment, recycling is very limited and therefore the issue of high-level radioactive waste is not as critical as it would be with recycling. The real issue is how we manage spent fuels in the long term. We need to have a good regulation and monitoring system, and keep spent fuels as a potential future fuel source without hurrying too much into recycling. Short-to-medium term we still have enough uranium and thorium resources, so I do not see the urgency of recycling. Even to build a new reactor takes easily 15–20 years, so recycling may become an issue in only about 20 years.

Nuclear energy is a controversial issue for many. What is your response to these people?

The important thing is a transparent and science-based approach with high credibility that enhances confidence in nuclear energy not only from the public but also from those owning, operating, managing and regulating all this. Therefore I feel an attitude often referred to as constituting 'safety culture' based on openness, transparency and sharing of experiences and lessons is the key issue. In many ways, our agency can support and promote this and make nuclear energy a safe, reliable and clean form of energy.

Interview by Joerg Heber