As the Covid-hit world steps into 2021, while the pandemic has been raging for nine previous months, the nuclear industry is displaying a change in mindset in favour of small modular reactors (SMRs) for the production of clean and reliable energy to help combat the urgent threat climate change. While for decades past, the role models have been large nuclear reactors with capacities of between 1,000-1,200 MW that can each cater to over a million households, SMRs come with a maximum capacity of 300 MW, requiring much less capital and land outlay, as well as less time to construct.
Although by their very nature SMRs are especially suitable for Asian nations, particularly for the ease in setting them up in remote areas, these are, in recent times, also finding favour with policy makers in the developed world. Among the high profile proponents of SMR technology is the new US President Joe Biden. The UK government has recently introduced a plan targeting zero emissions by 2050, with a promise to allocate $700 million to build new nuclear plants, including SMRs.
Noting that the climate crisis is a direct result of energy production and use, the US-based Science Council for Global Initiatives President, Thomas Blees points out that nuclear energy is the only alternative since scaling up is impossible with renewable sources like solar and wind. “ One pound of nuclear energy is the equivalent of 5,000 barrels of oil, and without producing carbon emissions. Nuclear energy meets the bill in tackling the four major issues of safety, cost of development, waste disposal and weapons proliferation”, Blees declared at the recently held NEXT 75 global youth conference.
According to Blees, the fastest and most efficient way to deal with the energy issue is for small self-contained nuclear plants on board ships, which could then travel via sea and make shore stops to sell power to many countries. He noted how Russia has already shown the way in this direction with the floating nuclear power plant (FNPP) Academic Lomonosov commissioned last year. “Building large nuclear plants is very expensive, while most governments lack such resources. Instead, the electricity costs such FNPP work out to $1 per watt,” Blees said. “It is estimated that such ships (FNPPs) with total capacity of 400 gigawatt (GW) can be built in a year, using unused shipyards”, he added. While wider deployment of SMRs is expected to begin over the current decade, two reactor units of KLT-40S design are already in operation in Russia aboard the world’s first FNPP built by the Russian state atomic energy corporation Rosatom. The Akademik Lomonosov is currently the only SMR power plant in commercial operation after its connection to the grid in Russia’s remote Chukotka region.
In its report on SMRs – Advances in Small Modular Reactor Technology Developments – published in October 2020 as a guide that can help countries identify suitable nuclear reactor designs, the International Atomic Energy Agency (IAEA) provides the latest data and information on SMRs around the world, including detailed descriptions of 72 reactors under development or construction in 18 countries. Expanding on an earlier IAEA report on SMRs, this booklet provides annexes on waste management and disposal, as well as a section on very small SMRs called microreactors.
Unlike large power reactors with capacities in the range of 700-1,000 MW, SMRs typically have a capacity of up to 300 MW and are built largely from prefabricated components assembled on site. They are designed for less upfront capital and have wider financing schemes. Their modular nature also allows for scaling up capacity by adding units according to demand. According to the IAEA, SMRs are also better suited to operate flexibly in tandem with variable renewable energy sources such as wind and solar, as well as for non-electric applications such as seawater desalination, district heating and hydrogen production. SMRs permit increased safety by providing among others, more efficient passive heat removal from the reactor vessel and greater quality control. These also have much lower land requirements, lesser delays in construction and involves significantly smaller displacement and rehabilitation of population displaced through land acquisition that would otherwise be necessary for conventional nuclear power projects (NPPs). “This is the decade of SMR demonstrations, which could potentially determine front runners for the expected economy of series production. There is high level of innovation”, says IAEA’s head of planning and economic studies Henri Paillere.
A 2016 report by the Organisation for Economic Cooperation and Development (OECD) arm Nuclear Energy Agency (NEA) titled “Small Modular Reactors: Nuclear Energy Market Potential for Near-term Deployment” has said that up to 21 gigawatt (GW) of SMRs could be added globally by 2035, amounting to around 3 percent of total installed nuclear capacity.
Last year, the Helsinki-based VTT Technical Research Centre announced the launch of a project to develop a small modular reactor for district heating in Finland which aims to phase out its coal-fired thermal energy production by 2029. VTT has been involved in projects examining the opportunities and deployment of SMRs. At the European level, it is coordinating the ELSMOR (European Licensing of Small Modular Reactors) project, launched in 2019. It is also leading one of the work packages of the European Research and Innovation project McSAFE, launched in September 2017. That project is developing the next generation calculation tools for the modelling of SMR physics. VTT’s selected reactor models for consideration include the HTR-PM pebble-bed reactor currently being constructed in China, and Terrestrial Energy’s Integral Molten Salt Reactor developed in Canada.
Various major companies worldwide have invested in SMR tehnology, while reactor designs have emerged from firms such as Rolls-Royce Holdings, NuScale Power and Terrestrial Energy, which has drawn investment from Microsoft co-founder Bill Gates. For instance, while the UK-Dutch-German consortium Urenco is exploring SMRs cooled by gas instead of water, others like Moltex Energy and Terrestrial Energy are working on a molten salt reactor.
Rolls-Royce, which is leading a consortium for Britain’s SMR project announced, in February last, its plans to install and operate SMRs built in the UK by 2029. Its SMR designs, which are much smaller than traditional pressurised water reactors (PWRs), are expected to produce about 450 MW power. The consortium plans to manufacture 10-15 SMRs, as also target an export market estimated at $328 billion according to the company.
The Canadian Nuclear Laboratories has recently unveiled its proposals for SMRs as a clean energy solution for the mining industry.With 40 percent of a mine’s energy usage being related to heating and ventilation, Canada’s “SMR Roadmap” report has indicated that SMRs could offer significant cost savings compared to diesel generation, particularly for remote industrial operations.
Argentina is developing the 25 MW CAREM SMR, which is intended for small electric grids and may also support seawater desalination, with construction of the prototype nearing completion. China’s HTR-PM, a prototype high temperature gas cooled SMR located in Shidao Bay, is expected to begin operations this year. The reactor is cooled by helium and capable of reaching temperatures as high as 750 degrees Celsius, making it suitable for non-electric applications such as district heating and hydrogen production.
Taking the case of India, which boasts of one of the bigger civilian nuclear energy programmes in Asia, and has significant reserves of thorium, the small thorium cycle-based high temperature gas-cooled reactors (STGRs) of 20-40 MW sizes allow the possibility of major cost and time saving by eliminating the chances of nuclear accidents, which has been highlighted in the past by the IAEA.