Nuclear fission is a major low-carbon energy source. In 2015 it provided 10.7% of the world’s electricity, behind hydropower (16.4%) but significantly ahead of wind, solar, geo, biomass and waste, which together contributed 6.7%. Following a post-Fukushima decline, nuclear power generation has been increasing slowly since 2012 (it grew 1.3% from 2014 to 2015, while wind and solar grew 17% and 33% respectively, to 3.4% and 1.0% of the total).
The role of electricity , which currently accounts for 20% of final world energy use (more in developed countries), is expected to grow substantially. New nuclear build is beginning, or is under consideration, in many countries and it seems certain that the importance of nuclear energy will grow in absolute, if not in percentage, terms.
The expansion of nuclear electricity generation is, however, still held back in many countries by concerns about cost and perceptions about safety, which new nuclear fission reactors must address. The next generation of nuclear reactors (Generation IV) will offer electricity generation with passive safety, as well as high temperature process heat for hydrogen production and desalination. Some designs may also re-use nuclear waste as fuel, closing the nuclear fuel cycle to reduce both the demand on uranium supplies and the volume of waste needing long-term storage. These reactors are likely to be generating significant power by the middle of the 21st century, following prototype development over the coming decades.
In the longer term nuclear fusion, which powers the sun, offers a future of sustainable, low carbon electricity generation. It involves the release of energy by fusing light atomic nuclei, rather than splitting (‘fissioning’) heavy nuclei. Fusion is a very attractive source of energy – almost unlimited in potential, with few of the downsides of nuclear fission – but it is very hard to master.
Research in Oxford
Work in Oxford addresses a wide spectrum of nuclear research, from developing the scientific understanding of nuclear materials and processes for fission and fusion energy through to the socio-economic impacts of new nuclear energy systems. The Oxford-Bristol Nuclear Research Centre, now part of the South West Nuclear Hub works closely with the nuclear industry and its stakeholders to identify and address important topics in both fission and fusion. Oxford is also a founding partner in the new National Nuclear User Facility (NNUF) at the Culham Centre for Fusion Energy, which will extend the application of our advanced methods for the testing and characterization of materials for nuclear power generation to active samples.
The economic and safe operation of nuclear plant requires an understanding of the ways that materials age in aggressive environments. This is important both for generating the safety cases for life-extension of the current fleet of nuclear power stations, and for designing future materials for Generation IV fission and fusion plants that will place even greater demands on engineering materials. Oxford’s current research portfolio, across the departments of materials, engineering, chemistry and computer science, includes work on stress corrosion cracking mechanisms in corrosion resistant alloys in current plant; interactions between residual stress and creep life in stainless steel welds in nuclear systems; the enhancement of zirconium fuel cladding alloys for improved safety and performance; fracture resistance in nuclear graphite and high temperature ceramic composites for high temperature reactors; the development of oxide-dispersion strengthened steel alloys for extreme environments; irradiation-tolerant materials for fusion energy; and the chemistry of actinides in nuclear waste and robotic sensory networks to monitor stored nuclear waste. All of this research is in collaboration with nuclear stakeholders, national laboratories and nuclear industries in the UK and internationally.
Oxford’s physicists work on understanding the behaviour of the large volume of gas, heated to over ten times the temperature at the centre of the sun, that will form the core of a fusion reactor based on ‘magnetic confinement’. The methods and theory of the alternative ‘inertial laser-fusion’ reactor are also addressed, using the tools and concepts of astrophysics. Oxford research also investigates the new and improved materials that are critical for fusion energy: including high-temperature super-conductors, reduced-activation steels to eliminate long-lived waste, radiation-resistant copper alloys for heat extraction components and plasma-resistant tungsten.
Forming a balanced view on the future of nuclear power requires understanding and information on future technologies and their role in policy and governance. Defining the risks, safety and environmental impact of nuclear energy are critical for public and regulator acceptance of the technology, and the next generation of nuclear power systems must be demonstrably safer, proliferation resistant and efficient. The Oxford Martin School provides a forum for interdisciplinary research on nuclear futures and the Blavatnik School of Government is building a programme on nuclear security in the broadest sense. Drawing on the experience and perspectives of policy researchers from across the world, including a wide community in Oxford, and from a broader base than is traditional in nuclear and international studies, these programmes will take an inter-disciplinary and practical approach to nuclear and international security issues, addressing regional and international security (deterrence, proliferation), nuclear energy and the environment (local and global), domestic security and regime implications, and ethics.