Nuclear Energy
Summary
Nuclear energy has been around for more than half a century and is one of the safest, cleanest, and most reliable sources of energy. Large-scale nuclear is a very low-carbon technology and, crucially, takes up a small land footprint (unlike wind and solar). Hinkley Point C, a nuclear power station on track to open in the UK by the end of 2026, will power ~6 million homes from just a quarter of a square mile (Department for Business, Energy & Industrial Strategy). The biggest hurdles to nuclear fission are mostly in regulation and a negative public perception, so a career in policy or advocacy is likely to be the most impactful in this area.
Published: 3 May 2023 by Jessica Wen
Bottlenecks
Policy
After concluding that nuclear power, specifically advanced nuclear reactors, was very promising for large-scale GHG reduction, Giving Green conducted some shallow dives into several US-based organisations advocating for advanced nuclear reactors.
The Clean Air Task Force is another organisation aiming to increase deployment of nuclear energy, supporting a broad portfolio of commercially-available and market-competitive nuclear energy options.
“Nuclear science and engineering is an advanced field, where applications are based on the detailed knowledge and appreciation of complex nuclear phenomena, often occurring in extreme conditions” (Frontiers in Nuclear Engineering). Being able to explain and communicate these concepts and data, while critically assessing risks and benefits, could tackle negative public perception by increasing understanding and education in a broader audience. (See the section in Climate Change on Ways you can contribute to climate without being an engineer.)
Technical work: nuclear fission
If you wanted to remain in a technical field, working as a nuclear engineer in research could be a high-impact option. R&D into nuclear fission has slowed down significantly and currently receives much less funding than other energy sources. This could make nuclear fission a neglected intervention in climate change. Some impactful research areas could include:
Thermal storage
The design of modern commercial nuclear power generators means that they operate most efficiently when continually producing electricity. However, due to the fluctuating power demand and supply, the consistency of nuclear plants becomes a disadvantage when compared to other intermittent energy sources.
Thermal energy storage would allow current-generation nuclear power plants to store any excess energy generated as heat, which improves nuclear energy competitiveness and civilisation’s overall access to clean, on-demand electricity.
Advanced Modular Reactors (AMRs)
Figure 1: NuScale Power Reactors. ©NuScale Power, LLC, All Rights Reserved (Office of Nuclear Energy)
Advanced reactors are “safer, cheaper, more flexible, more efficient, and easier to deploy than traditional reactors [...] Small advanced reactors can be standardised and constructed in factories, which could enable “learning by doing” and drive down costs.” (Giving Green)
Mass-manufacture of modular nuclear reactors could result in costs decreasing due to economies of scale.
Nuclear co-generation in advanced nuclear reactors could allow the heat generated to be used directly for energy-intensive industrial processes, such as hydrogen production (see next section on zero-carbon fuels), water desalination, and decarbonising heavy industry (which has historically been very difficult to decarbonise). This could contribute to large reductions in carbon emissions while the costs remain on par with fossil-fuelled plants in the same area.
Advanced nuclear reactors could replace the heat source from coal plants (e.g. replacing the coal boiler with an advanced reactor). TerraPraxis is helping to identify high-potential coal plants for conversion to nuclear power, and developing digital tools and a kit to help coal plant owners reuse parts and infrastructure.
We believe (with medium confidence) that AMRs have the highest potential to tackle emissions from energy generation and to decarbonise heavy industry.
Zero-carbon fuels from nuclear energy
Zero-carbon fuels (e.g. hydrogen and ammonia) are a core component of many countries’ strategies to decarbonise their industries. However, the production of these zero-carbon fuels without producing carbon dioxide is a challenge in itself.
Nuclear technologies have the potential to generate high-quality hydrogen cleanly and efficiently at the scale that’s required to drive decarbonisation in emissions-heavy energy sectors, crucially with a small land footprint in comparison to other means of hydrogen production.
The technology has been long proven, so the main technical research needs are into unanswered questions on implementation (like how to adapt current gas infrastructure to hydrogen or ammonia) rather than fundamental scientific barriers.
Ocean-based reactors
Due to the potential advantages of ocean-based reactors (floating or fixed) in safety, security, siteability, and cost, these reactors have been utilised by numerous navies around the world for hundreds of reactor-years.
Although Russia has deployed an ocean-based nuclear energy facility (with the US, China, and others investigating these opportunities), commercialised floating reactors are still very rare.
Startups like Seaborg Technologies are hoping to power developing countries with floating nuclear reactors.
Preservation of existing units
Although nuclear energy provided over a quarter of the world’s low-carbon energy in 2019, premature closure of nuclear plants could seriously hinder the transition to zero-carbon energy.
New nuclear technologies could become more expensive to deploy as currently operating nuclear plants retire and sites close.
Being able to continue operating existing plants preserves the manpower, knowledge, and skills needed to operate the next generation of plants.
Historically, the fastest way to increase capacity is to add a unit to an existing site. Being able to support and preserve existing units paves the way for the next generation of plants.
Nuclear waste
Research into how to reduce the burdens associated with unspent nuclear fuel would break down a major barrier to the expansion of nuclear energy. Increasing fuel efficiency requires not only optimising the choice of its chemical composition and microstructure (Tonks et al., 2017), but also the selection of high-performance cladding materials and operating conditions. This area is particularly in need of materials scientists/engineers.
Extracting the plutonium and uranium allows approximately 97% of the used fuel to be recycled to be used to generate more energy. However, this is not widely practiced in reactors in the US.
Other challenges
No or minimal operator intervention in the event of an accident — automation and robotics engineers may be particularly useful, as well as physicists and mathematicians for multiscale multi-physics computer simulations (Eyre and Matthews, 1993; Gaston et al., 2009, 2015), digital twins, and modelling to improve understanding of operating conditions and safety of nuclear reactors.
Development of advanced structural nuclear materials (Cabet et al., 2019; Zinkle et al., 2019; Rieth et al., 2021) to improve reactor longevity, reduce waste, lower maintenance costs. This area is applicable to both nuclear fission and nuclear fusion, and seems particularly suited to materials scientists/engineers.
Technical work: nuclear fusion
Nuclear fusion has seen a meteoric injection of $3bn+ in private investment over recent years, and, if commercialised, has a huge potential to decarbonise energy. However, there are significant technological (e.g. radiation-resistant reaction vessel materials) and commercial (e.g. downtime and maintenance costs) barriers that must be overcome.
It seems that a Ph.D. is required for most jobs in a national fusion lab or start-up, but that a fusion Ph.D. makes you very employable in the field. From our limited understanding of the industry, start-ups generally seem to have ambitious, even unrealistic, timelines (some say it will work within a decade), and it is predicted that they are unlikely to survive the multiple decades until their approaches to fusion actually work (it’s long been advertised as just 20 or 30 years away!)
It may be more effective to work on tried-and-tested nuclear fission. However, we have some members working on nuclear fusion, so we can help you get in touch with them to understand their viewpoints on the industry.
Conclusion
Although there are technical bottlenecks in producing the next generation of nuclear fission reactors, the main bottlenecks are in policy and public perception. As a result, we recommend engineers interested in increasing nuclear energy use to consider transferring their technical skills to policy and advocacy.
However, if engineers would like to work in a technical nuclear field, we suggest developing Advanced Modular Reactors as a potentially high-impact way to tackle GHG emissions and decarbonise heavy industry.