The energy industry is facing a crossroads. The future is fusion, suggests Dr. William Nuttall, but funding must come from private money – and where better to go than to the major oil companies.
Crude oil prices are on the rise. Stability in the Middle East is eroding. There are fears that energy policy may be heading towards a situation not unlike the (literally) dark days of the early 1970s.
Back then nuclear power implied a reliable and more sustainable future. Much research was done into nuclear fission to reduce reliance on unreliable domestic and international sources of fossil fuels.
These days the UK’s natural gas resources are depleted, international oil markets are nervous and nuclear power is a mature technology. Nuclear energy has provided us with electricity for almost 50 years.
Roughly a quarter of the electricity used in the UK comes from a British, or French, nuclear power station. Nuclear energy’s links to electricity are so strong that they are regarded as being two sides of the same coin.
It is conceivable, however, that in the long term nuclear energy might have little to do with electricity generation. Such thinking has been embraced by the US-led international Generation IV project.
A key idea emanating from General Atomics of San Diego is that nuclear energy should be used to produce hydrogen to power vehicles and industry.
Hydrogen and electricity have fundamentally similar attributes. They are not fuels, they are energy ’vectors’. They are produced using energy from a primary fuel (such as coal, gas or nuclear fission) and are used to transfer that energy in a usable form to another location. As a vector, however, hydrogen has a key potential benefit: it can be stored in bulk. By contrast, electricity requires a synchronised balance of supply and demand.
Key to the production of hydrogen using nuclear energy will be heat. At present nuclear power stations produce heat which produces steam which is used to generate electricity. Hydrogen production can use nuclear heat directly for the catalytic thermochemical ’cracking’ of water. One candidate reaction, known as the sulphur-iodine cycle, involves sulphuric acid and iodine. Once running the only inputs to the process are heat (at more than 750 degrees C) and water, and the only outputs are hydrogen and oxygen.
The Generation IV International Forum has selected six nuclear fission reactor concepts from which technologies for nuclear energy in the middle of the 21st century are likely to emerge.
Of these four have the potential to be developed for hydrogen production. On the basis that hotter is better, one technology in particular, the Very High Temperature Reactor, is likely to be extremely well suited to thermochemical hydrogen production. This technology builds upon British experience with gas-cooled reactors and is attracting particular interest within the British nuclear community.
While the possibility of linking the hydrogen economy to a new generation of nuclear fission power plants is both interesting and challenging, even greater opportunities for nuclear hydrogen apply to a more uncertain form of nuclear energy: nuclear fusion. The fastest track to a nuclear fusion power plant lies via the international research reactor ITER. At present there is an unresolved tussle between France and Japan as to where this big research machine should be located.
Conventionally, nuclear fusion is expected to provide large-scale base-load electricity. However, matching fusion engineering to the electricity industry’s needs in terms of plant size and generation reliability will be a key challenge. The electricity industry around the world has moved away from technocratic monopolies tolerant of engineering difficulties towards markets with high penalties for failure.
The culture of today’s electricity industry is short-term and risk-averse. It values flexibility and responsiveness and is nervous about capital-intensive technologies with long construction and licensing requirements. Fusion could face difficulties matching to the needs and culture of the electricity industry.
By contrast the oil industry is risk taking and comfortable with highly complex engineered systems in fuel extraction and processing. It also retains the vision necessary to nurture grand opportunities like fusion.
The chemical engineering of thermochemical hydrogen production would have key similarities with the refining operations of the big oil majors. The major oil companies already have vast distribution infrastructures for fluid energy products.
Furthermore, nuclear fusion power will become available at a key time just before the middle of this century as fossil fuel reserves finally run out. The problem in linking fusion to hydrogen will be the need to stop fusion’s radioactive tritium contaminating the hydrogen released for sale. However, monitoring to ensure that only safe product could be sold would thankfully be straightforward.
Fusion research has benefited from public support for decades. I suggest that ITER should be the last major fusion reactor built using public money. Steps towards demonstrators and prototypes should involve substantial private support. The fusion community could do far worse than to look towards the major oil firms for help.
Dr. William Nuttall is director of the MPhil in technology policy at Cambridge University