Small modular reactors will be joining the grid as soon as this year and represent a way for the nuclear industry to address problems of cost and schedule that have affected large units, participants in the World Nuclear Association's annual conference said last week.
However, such reactor designs must overcome obstacles if they are to be adopted widely, some cautioned, noting that they must compensate for the economies of scale that benefit larger units and resolve regulatory challenges to be licensed more easily.
Rosatom considers the Akademik Lomonosov, a ship-mounted nuclear plant, to the be the first SMR in the world to operate, Evgeny Pakermanov, president of Rusatom Overseas, said during the conference's closing session September 6. The two reactors on the ship will provide 70 MW to the area around the Arctic city of Pevek once the vessel is towed there and the units are connected to the grid, he said.
Grid connection is expected before the end of the year, Pakermanov said.
Last week, Rosatom said it would also be building a series of land-based SMRs in the sparesely-populated Yakutia region. Those units are to be 50-MW RITM-200 reactors derived from those used on Russian icebreakers, and the first units will be operating by 2027, Pakermanov said.
SMR offer the opportunity for simpler new plant projects than those with which nuclear energy has been associated in recent decades, said Dominique Miniere, president of Ontario Power Generation's nuclear operations, during a September 5 session devoted to SMRs at the conference. His company, for example, has embarked on a C$12 billion (US$9.1 billion) project to refurbish four Candu units at the Darlington site, and has had to plan meticulously because previous such refurbishment projects went over budget and were delayed.
SMRs present a somewhat different safety profile, especially advanced reactor designs that depend on passive phenomena like convection and gravity to keep fuel cool in all situations, Miniere said.
Smaller reactors also require a smaller investment, so the decision to build them can be easier, he noted.
The nuclear industry in Europe and North America has struggled to complete complex new reactor construction projects, Miniere said. Some projects have tripled in budget and almost all have fallen considerably behind schedule, he noted.
"At least in the Western world today, we have no success story in new nuclear. We have a lot of difficulties," he said.
Reactor projects in Finland, France and the US featuring new Generation III+ reactors have experienced significant delays and cost overruns.
"A complementary solution could be SMRs, because they are simpler projects," he said. More work can be done in a manufacturing facility, making on-site work easier to plan and execute, he said. And the financial community is more likely to finance lower-cost SMR projects.
In addition, there is growing government support for SMR deployment, several speakers at the WNA event said. Canada has developed a government roadmap to small modular reactor construction, which has identified needs for small reactors for a variety of purposes, Miniere said.
OPG has potential interest in SMRs to serve its customers, Miniere said, and in March sought proposals for SMR plant deployment. Ten vendors responded with information about their designs, which OPG is reviewing.
"We are ready to move, but we must move in a cautious way," he said. It will be some years before the decision is made, Miniere noted.
In the US, the first SMR unit is expected to begin operating in 2026, said Suzanne Jaworowski, senior adviser on policy and communications to the Office of Nuclear Energy at the US Department of Energy. That reactor is part of the planned Utah Associated Municipal Power System plant at the Idaho National Laboratory. UAMPS, an association of municipal power companies in the West, is developing an application for a combined construction permit-operating license to build and operate 12 NuScale reactor modules at INL.
The first unit to operate would be leased to DOE, which would use it as a test and research reactor, Jaworowski said during a conference presentation September 5. The other 11 units would be used to generate power for UAMPS members and other utilities in the region.
However, an even smaller reactor may be the first in the US to operate, Jaworowski said. A microreactor may be built in connection with US Department of Defense procurement efforts as soon as 2023, she said, without elaborating. Microreactors are being promoted as units of less than 15 MW that can provide power to isolated communities, mining and industrial facilities and military bases.
Four Canadian provinces are considering SMR construction, said Kevin Lee, a senior policy officer at Canadian Nuclear Safety Commission, during the same session. The Canadian regulator has engaged with a variety of small modular and advanced reactor developers to prepare for or carry out a pre-licensing vendor design review, an optional feature of Canada's regulatory framework.
Eleven vendors are currently engaged with CNSC on such vendor design reviews, including NuScale Power, which recently determined to do so, Lee said. One developer, Global First Power, has submitted a request for a license to build and operate a unit at the government's Chalk River nuclear laboratory, he noted. Global First Power is working with reactor developer Ultra Safe Nuclear on the unit's design. Ultra Safe Nuclear is developing a 5-MW high-temperature gas-cooled reactor that uses ceramic fuel.
One of the benefits that SMRs offer is that they can be deployed more quickly than large reactors because they are designed to be built in a factory setting and then shipped to plant sites. As a result, civil construction of a plant can take place at the same time as assembly of the reactor modules, said Lenka Kollar, director of strategy and external relations for NuScale. As a result the construction time of a NuScale reactor module is expected to be about three years.
NuScale is taking steps to develop a supply chain for the reactor modules, Kollar said.
FINANCIAL BENEFITS OF SMALLER UNITS
Celestine Piette, innovation manager for Belgian reactor operator Tractabel, said advanced SMRs could address many of the issues that prevent nuclear power from being competitive in regions with deregulated electricity markets. In such markets, a combination of high levels of debt and potentially high interest rates as well as low power prices challenge the viability of reactor construction, Piette said. In addition, equity investors in such projects would demand higher returns because risks associated with regulatory questions, first-of-a-kind construction problems and potential policy and political concerns combine to reduce further the competitiveness of nuclear plant projects, he said.
Advanced SMRs would address many of those issues, although the new technologies in use and the dependence on policy decisions regarding nuclear energy would require government support for initial units, Piette said. Once supply chains are established, private investors might provide financing for further advanced SMR projects, he noted.
"The SMR approach is quite well-suited and designed to mitigate and even eliminate these risks," Piette said.
OVERCOMING ECONOMIES OF SCALE
Smaller reactors must overcome the inherent efficiencies that come from the scale of gigawatt-class reactors, Bernard Salha, director of research and development for French utility EDF, said during a session at the conference September 6.
"We have to realize that the final price, euros per mehawatt-hour, might be a little higher for SMRs," Salha said.
The benefit of the smaller units will be their modularity, which can allow for more flexible operations, complementary to intermittent renewables, and the fact that their price will decline if sufficient numbers are built in series, Salha said, noting, "We're going to have a world with SMRs and big reactors, working together."