[Energy Odyssey] 10: SMRs to 'kill three birds with one stone'... Global race gathers pace

II. Overcoming the Energy Crisis Through Technological Innovation
More than 73 SMR designs under development worldwide
Rising power demand from AI data centers fuels interest
SMRs expected to boost energy security, carbon neutrality and industrial growth
Faster U.S. licensing... commercialization expected in the early 2030s
South Korea targets 40% of global market by 2035
"Allow PPAs and resolve market uncertainty"

Editor's NoteThe importance of energy is greater than ever amid supply chain crises caused by recent conflicts in the Middle East and the government's megaprojects. South Korea faces the difficult task of achieving energy security, carbon neutrality and economic growth at the same time, while relying on overseas sources for most of its primary energy. Reporters covering energy issues on the ground are examining a range of current challenges and exploring alternatives in this series of feature articles.

Ontario Power Generation (OPG) is building GE Vernova Hitachi's BWRX-300 small modular reactor (SMR) in Canada's Darlington area. Ontario Power Generation

In the age of artificial intelligence (AI), small modular reactors (SMRs) are rapidly emerging as a solution that can deliver energy security, carbon neutrality and industrial growth at the same time. As countries around the world compete to gain an early lead in the SMR market, South Korea has joined the race in earnest by designating SMRs as a national strategic technology.

According to the Korea Institute of Nuclear Safety (KINS), as of June 2026, 73 SMR designs were registered in the International Atomic Energy Agency's (IAEA) Advanced Reactors Information System (ARIS). The United States leads with 22, followed by Russia with 13 and France with eight.

South Korea has four designs registered: the Innovative Small Modular Reactor (i-SMR, Korea Hydro & Nuclear Power), which is currently undergoing a standard design approval review by the Nuclear Safety and Security Commission; SMART (Korea Atomic Energy Research Institute), which received standard design approval in 2024; BANDI (KEPCO Engineering & Construction); and SALUS-100 (Korea Atomic Energy Research Institute).

The number of SMRs under development in South Korea rises further if designs in the early stages of development are included. In addition to SALUS-100, a sodium-cooled fast reactor (SFR), the Korea Atomic Energy Research Institute is developing a high-temperature gas-cooled reactor (model name: HECTAR), a molten salt reactor (MARINA) and a heat pipe reactor (Nuspace Power).

The institute is pursuing commercialization with Helios, a 250-MW model scaled up from SALUS-100, which has an electrical output of 100 megawatts (MW). Among domestic private-sector companies, BIZ is developing a high-temperature gas-cooled reactor called BeSMART.

SMRs: A solution to power needs in the AI era, drawing closer

SMR refers to a small reactor with an electrical output of 300 MWe (megawatts-electric) or less and a thermal output of 1,000 MWt (megawatts-thermal) or less. Large nuclear power plants typically have an electrical output of 1,000 MWe or more. SMRs feature an integrated design, with major components such as the reactor core, control rods, coolant pumps, steam generators and pressurizers housed in a single vessel. They can be manufactured as modules in a factory, transported and then assembled on site.

SMRs also use a "passive safety system" that removes heat from the reactor core through natural circulation, even without an external power supply. They are designed to shut down safely even in natural disasters such as the Fukushima earthquake. Reactors with a lower output than SMRs, in the range of 10 to 50 MWe, are sometimes called micro modular reactors (MMRs).

SMRs are broadly divided into light-water reactors, which use water as a coolant, and non-light-water reactors, which do not. South Korea's SMART and i-SMR are light-water reactors, while sodium-cooled fast reactors, high-temperature gas-cooled reactors and molten salt reactors are non-light-water reactors. Non-light-water reactors are also known as "advanced nuclear reactors" or Generation IV reactors.

As recently as two to three years ago, SMRs were seen as a distant prospect. But as countries have accelerated their development in recent years, commercialization has moved closer. A major factor behind the race to develop SMRs is the sharp increase in electricity demand driven by AI.

Countries are looking to SMRs as a source of power that can provide a stable, 24-hour supply to AI data centers and semiconductor plants. U.S. tech giants such as Google and Meta have signed a series of power purchase agreements with SMR developers to secure electricity for their data centers.

Large nuclear power plants are built far from areas of demand, such as along coastlines, where safety and public acceptance are easier to secure. Long-distance transmission networks must also be built. By contrast, SMRs, with their enhanced safety, can be built close to areas of demand. In addition to generating electricity, they can be used for a range of purposes, including hydrogen production, process heat, desalination and ship propulsion.

U.S. aims to complete licensing within 18 months, accelerating commercialization

The United States is leading the race to develop SMRs. In 2019, it established a phased licensing process for "advanced reactors" through the Nuclear Energy Innovation and Modernization Act (NEIMA).

Then, in 2024, the Accelerating Deployment of Versatile, Advanced Nuclear for Clean Energy Act (ADVANCE Act) enabled the Nuclear Regulatory Commission (NRC) to expedite approval and licensing reviews for next-generation reactors, including SMRs.

Progress accelerated further under President Donald Trump's second administration. President Trump has issued a series of executive orders to accelerate the deployment of nuclear power.

In particular, an executive order on "Reforming the U.S. Department of Energy (DOE) Reactor Testing Framework" authorized the DOE, rather than the NRC, to approve test programs for next-generation reactors. This allows test reactors to be approved and operated under the DOE's authority, although commercial reactors still require NRC licensing.

Under the program, the DOE selected 11 projects from 10 companies for its pilot program. The executive order directed that at least three reactors reach criticality by July 2026. In fact, five reactors had reached criticality as of August 2026.

In addition, an executive order on "NRC Reform" directed that licensing procedures for new nuclear power plants be completed within 18 months. An executive order on "Rebuilding the U.S. Nuclear Industrial Base" includes provisions to fund the restart and construction of nuclear power plants.

Preparations for commercialization are also moving ahead quickly. The United States has moved beyond the licensing stage and entered the full-scale construction phase. Multiple SMRs are expected to begin commercial operation in the early 2030s.

TerraPower is building Natrium, a sodium-cooled fast reactor (SFR), in Kemmerer, Wyoming. Natrium became the first commercial SMR to receive a construction permit from the U.S. NRC, in March 2026. It has an electrical output of 345 MWe and is expected to be completed in 2031 or 2032. Meta has signed power purchase agreements with TerraPower for a total of 2.8 GW.

TerraPower also maintains close ties with South Korea. SK Innovation and SK Inc. invested in TerraPower in August 2022 and became its second-largest shareholder. SK Innovation then transferred part of its stake to Korea Hydro & Nuclear Power in January 2026. This formed a trilateral alliance among TerraPower, SK Group and KHNP.

GE Vernova Hitachi, a joint venture established by GE Vernova and Hitachi, is pursuing commercialization of the BWRX-300, a light-water SMR with an electrical output of 300 MWe. On September 29, the U.S. NRC issued the Tennessee Valley Authority (TVA) a construction permit for a BWRX-300 at the Clinch River site in Oak Ridge, Tennessee. It was the first construction permit for a BWRX-300 issued in the United States.

Before that, Ontario Power Generation (OPG) received a construction permit from the Canadian Nuclear Safety Commission for the first BWRX-300 unit in April 2025 and is currently carrying out construction.

X-energy plans to build Xe-100, a high-temperature gas-cooled reactor (HTGR), at Dow Chemical's Seadrift site in Texas. The project will comprise four units, each with an electrical output of 80 MWe, for a total of 320 MWe. The company expects to receive a construction permit in the second half of 2026.

Amazon has invested about $500 million in X-energy and plans to secure 5 GW of power by 2039 using Xe-100 SMRs. Doosan Enerbility is participating as a supply partner for X-energy's main reactor equipment.

Kairos Power is building Hermes-1 and Hermes-2, molten salt reactors (MSRs), in Oak Ridge, Tennessee. They are still demonstration reactors with a thermal output of 35 MWt, and the company aims to bring them online in 2028 and 2029, respectively. Kairos Power has signed a power purchase agreement with Google for 50 MWe.

NuScale Power is pursuing commercialization of its pressurized water reactor, VOYGR. It initially sought to commercialize the technology in Idaho, but the plan fell through after local power companies that had intended to purchase the electricity canceled their plans, citing economic viability concerns.

Each VOYGR module can generate 77 MWe of electricity. In May 2025, a model using six modules and capable of generating 462 MWe received standard design approval from the U.S. NRC. However, it has yet to receive construction and operating permits. NuScale Power is also pursuing an SMR project in Romania.

A number of South Korean companies are working with NuScale Power. GS Energy invested in NuScale Power in 2021, while Doosan Enerbility and Samsung C&T are also participating as partners.

South Korea targets 40% share of SMR market by 2035

Building on its experience in constructing and operating large nuclear power plants, South Korea is also accelerating efforts to become an "SMR powerhouse." On October 7, the government announced its vision of achieving a 40% share of the global SMR market, excluding China, by 2035 in its "Korea Green Transformation (K-GX) Implementation Plan."

As a carbon-free power source, SMRs can help achieve carbon neutrality and contribute to national energy security by replacing existing fossil fuel-based power plants. Exporting domestically developed SMRs can also drive industrial growth, delivering three benefits at once. This is why the government is supporting the SMR industry.

Experience in building SMRs could provide a foundation for South Korean construction and manufacturing companies to participate in global SMR projects. Doosan Enerbility, which is involved in multiple SMR projects at home and abroad, plans to build a dedicated SMR foundry in Changwon and manufacture more than 20 SMRs annually. In addition, Samsung C&T, Hyundai Engineering & Construction, HD Hyundai Heavy Industries, DL E&C, GS Energy, Samsung Heavy Industries, Hyundai Engineering and SK Innovation are participating in overseas SMR projects or have invested in them.

The first SMR to be built in South Korea is likely to be the Innovative Small Modular Reactor (i-SMR) developed by Korea Hydro & Nuclear Power. The plan is to obtain standard design approval from the Nuclear Safety and Security Commission by 2028, secure a construction permit and begin commercial operation in 2035. KHNP has selected Gijang, Busan, as the site for the country's first SMR.

To commercialize non-light-water SMRs, the government is also pursuing large-scale research and business development (R&BD) projects that involve the private sector from the early stages of development. A project to build ships powered by molten salt reactors (MSRs), with participation from the public and private sectors, including the Korea Atomic Energy Research Institute, construction companies and the country's three major shipbuilders, is expected to move forward. As one of its K-GX initiatives, the government said it would build eco-friendly SMR-powered ships capable of operating for more than 20 years without refueling. To accelerate the commercialization of SMRs, the government plans to amend the Restriction of Special Taxation Act in the first half of next year, 2027, to designate SMRs as a national strategic technology.

A new regulatory framework will also be needed to introduce SMRs based on non-light-water technologies, including sodium-cooled fast reactors, molten salt reactors and high-temperature gas-cooled reactors. The current framework is designed for large light-water and heavy-water reactors and cannot be applied to new reactor designs as is. In response, the Nuclear Safety and Security Commission drew up a "Roadmap for Establishing an SMR Regulatory Framework" in February 2026.

The core of the commission's SMR regulatory framework is a shift away from the existing "review after design completion" approach toward "parallel development of regulation and design." As part of this effort, the commission will introduce a pre-review system starting in November 2026. The aim is to identify whether regulatory standards can be applied and resolve uncertainties through communication between developers and regulators from the design stage onward.

TerraPower plans to apply for the domestic pre-review process through SK Innovation, its second-largest shareholder. Since TerraPower's Natrium reactor has already received a construction permit from the U.S. NRC, the company expects to move quickly through the domestic licensing process as well.

Denmark's Saltfoss Energy, formerly Seaborg Technologies, which is developing a molten salt reactor, is also considering whether to apply for the pre-review process. Saltfoss Energy is working with Samsung Heavy Industries and KHNP to build floating SMRs in South Korea. Floating SMRs are installed on barges, which can then be moved to where power is needed.

Kang Shinyoung, head of Saltfoss Energy's South Korea office, said, "There is also interest from Texas in the United States, so we are weighing whether to go through the U.S. licensing process or apply for South Korea's pre-review system."

The sodium-cooled fast reactor, high-temperature gas-cooled reactor, molten salt reactor and heat pipe reactor being developed by the Korea Atomic Energy Research Institute are also expected to make use of the pre-review system. The institute is conducting joint research on a sodium-cooled fast reactor with Hyundai Engineering & Construction, a high-temperature gas-cooled reactor with POSCO E&C, and a molten salt reactor with Samsung Heavy Industries and Hyundai Engineering & Construction.

Resolving uncertainties is key to SMR commercialization

In February, the National Assembly passed the Special Act on the Promotion and Support of Small Modular Reactor Development (SMR Special Act). The law, which took effect in September 2026, requires the government to establish a "Basic Plan for Small Modular Reactor System Development" every five years and establishes a Small Modular Reactor System Development Promotion Committee under the Nuclear Energy Promotion Commission,

The act also allows the government to support SMR research, development and demonstration, as well as the establishment of companies jointly funded by private-sector businesses and public institutions. The government may also designate areas where universities, research institutes and companies involved in SMR development are concentrated as special zones for SMR research and development.

Despite the act's implementation, energy industry officials say practical institutional reforms that can ensure profitability are needed for SMRs to be commercialized. The current SMR Special Act is limited to research reactors and demonstration projects, they say, so new support measures are needed to enable private power producers to enter the SMR market.

Building SMRs requires enormous costs, so initial construction expenses must be raised through project financing (PF). Profitability must be established early to secure financing. The nuclear industry is calling for power purchase agreements (PPAs) with customers to be permitted for SMRs as well.

Public acceptance is crucial to building SMRs. Although they are considered safer than large nuclear power plants, they still need to undergo a period of validation. Experts have proposed building SMRs on sites where coal-fired power plants have been shut down.

For investment in SMRs to continue, there must be confidence that construction will continue in South Korea. The nuclear industry is calling for the government to include additional SMRs in its 12th Basic Plan for Electricity Supply and Demand, which it is drawing up this year, to reduce market uncertainty.

This content was produced with the assistance of AI translation services.