Are small modular reactors the climate solution they claim to be? 

The SMR market is expected to reach 21GW by 2035, the Nuclear Energy Agency reported. 

Small modular reactors (SMRs) are increasingly becoming touted as a solution to the climate crisis. These compact nuclear reactors, with a capacity of up to 300MWe, are highly flexible and can be rapidly deployed to meet local energy demands. With this comes a growing interest to deploy SMRs, which the Nuclear Energy Agency projected to grow to 21 gigawatts by 2035. 

In this light, Asian Power spoke to three industry leaders with different perspectives on whether SMRs can deliver the promise of being the climate change fix. 

Philip Andrews-Speed
Senior Principal Fellow
Energy Studies Institute
National University of Singapore

In principle, SMRs could make a difference by supplying large quantities of reliable, low-carbon energy that is not intermittent. However, the problem is that they are unlikely to be deployed at a sufficiently large scale in the next 15 years, which is the period when significant reductions in carbon emissions must be made.

It is too early to assess whether SMRs will be safer than the safest large-scale reactors, as there are many SMR designs and a variety of underlying fuel and cooling systems. The key economic argument behind SMRs is that they are modularised and can be standardised, which means capital costs per megawatt of capacity can be significantly lower than for large-scale reactors. However, two issues need to be addressed. First, this has yet to be demonstrated in practice, and second, the companies making them will need a large number of orders before they can demonstrate the economic benefits of SMRs.

Renewables are better than SMRs in the short term, as they are already being manufactured and deployed at scale and are cost-competitive. However, it is possible that SMRs of different types could be deployed at scale in 20 years or more.

Mycle Schneider 
Founding Board Member, Spokesperson
International Energy Advisory Council

SMRs were designed to be fast, easy, and cheap to build, but they remain largely conceptual, with over 70 designs counted by the International Atomic Energy Agency. To date, they don't exist anywhere in the western world, with only two 30-megawatt (MW) floating prototypes in Russia and two 100MW high-temperature reactors in China. Construction of a 25MW reactor of domestic design in Argentina started in 2014, but its current grid connection is estimated for 2027. A 100MW design certified in 2012 in South Korea never found a buyer.

The only design that received general certification in the western world is NuScale in the US, but that certification was subject to solving several technical issues. Additionally, NuScale has increased the module size twice since certification, making it questionable whether it will be operational before 2030.

By the time SMRs could be available, significant progress should have been made to address the climate emergency. Even if series production were available, it would be too late to capture current market opportunities and much too late for the climate.

In terms of waste generation, SMRs would generate more spent nuclear and high-level radioactive waste per gigawatt of capacity than a standard GW pressurised water reactor. They would also bring about proliferation risks with the proliferation of weapons-usable nuclear knowledge, materials, and facilities.

Economically, SMRs would not be cost-effective due to their smaller size, which would lack economies of scale. NuScale, the most advanced design in the West, increased its projected construction cost by 75% from US$5.3b to US$9.3b, with a generation cost close to US$120/MWh. This makes it more costly than the most expensive large-scale nuclear plants currently under construction in Europe and the US.

Affordable and efficient options for reducing greenhouse gas emissions exist and can be quickly implemented. Solar and wind projects are affordable and have been implemented in Europe and India, and hybrid concepts that optimise technical solutions represent an untapped potential.

In terms of policy, the most cost-effective option for reducing greenhouse gas emissions as quickly as possible should be considered, as every dollar can only be spent once. SMRs are not currently an option and may not be available for the next two decades. The focus should be on implementing climate-effective options that are available and cost-effective.

Victor Nian 
Co-founder and CEO 
Centre for Strategic Energy and Resources

SMRs can definitely be a game-changer. When we look at large reactors in the aftermath of Fukushima, public sentiment is that they are probably not safe enough and are difficult to manage in the event of an accident. Older-generation technologies are also not deemed safe enough. Newer generation technologies, together with small modular reactors, are now believed to be a game-changer because they enhance safety and are much safer compared to before. They are also smaller, so there are economies of scale. There is a chance that countries can now choose SMRs as end-products rather than building one-of-a-kind large reactor projects. This is like buying a product and putting it on your product. From the product commissioning timeline and delivery timeline, from the perspective of product cost management, SMRs will be a lot easier compared to the large ones. On that count, SMRs will definitely be a game-changer, especially in the Southeast Asian context.

In terms of security, it is always there, but of course, SMRs can now manage those risks much better compared to large reactors. We also have the concept of a floating nuclear power plant, which is also an SMR, but the reactors are deployed onto a floating barge. There is some flexibility in sitting. You can now move a nuclear power plant out at sea.

In terms of cost, SMRs are still higher, as of today, but this will change as and when the SMR market begins to scale up, and the industry standardises with repeat product manufacturing. Rather than having large ones one at a time, we're producing SMRs in batches. If you look at the semiconductor industry, SMRs will also be expected to have cost reductions over time with scaling up.

Between renewables and SMRs, politically speaking, renewables have stronger support than nuclear energy in general, including SMRs. But SMRs are not always suitable for every geographical location, which is analogous to renewables.

In the case of Southeast Asia, not everywhere has green power from hydro. Similarly with SMRs. Of course, SMRs don't depend on climatic conditions, but in principle, SMRs would always prefer to have a certain degree of access to water in the event that something happens. Water is the last line of defence for most nuclear power plant technologies. Today, we do not really need that kind of last line of defence anymore because these reactors will not have the same Fukushima problem, as we saw a decade ago. They are much more flexible in terms of where they can be sited and how they can be cited. You have the option of land-based SMRs, which makes it much easier compared to large nuclear power plants. You also have floating SMRs. In the case of Southeast Asia, you have archipelagos such as Indonesia and the Philippines and large shorelines like Vietnam and Malaysia. These countries can actually have floating nuclear power plants. In fact, Singapore is also considering nuclear energy, although it's not really deciding in any direction. But in general, if you look at Southeast Asia, this is a good place to have SMRs. From that point of view, and other angles we're looking at, comparing SMRs and renewables is integration—smaller or more scattered electricity grids, which some people call a distributed access degree. If you have countries like China, India, or even Japan and Korea—they have a very large grid size and the demand is so much bigger as compared to the rest of Asia Pacific.

SMRs could be used to demonstrate their technology, scale up, and have multiple modules on the same site, particularly in areas where the grid sizes are relatively small. In Southeast Asia, the debate between renewables and nuclear is seen in places where the grid sizes are relatively small. Since nuclear is a baseload that produces electricity 24/7 and renewables are intermittent, integrating SMRs into the grid is much easier than renewables because the latter requires managing intermittency, variability, and their impact on the grid. With SMRs, the demand can be stepped up continuously. Therefore, SMRs will be a lot easier to integrate into the grid than large-scale renewables, making it more feasible to have 1GW of SMRs compared to 1GW of renewables in the Asia Pacific context. In conclusion, SMRs will be a lot easier to manage in terms of integration and will provide the greatest quality electricity as compared to renewables.