[C Tech Now] "Korea's i-SMR with Both Safety and Economic Efficiency... Closest to Commercialization"

Kim Hangon, Head of the Innovative SMR Technology Development Project Team

Over 90 SMRs are under development worldwide,
but commercialization is delayed due to economic feasibility.
i-SMR module production solves economic issues.

South Korea has decades of nuclear power plant operation experience,
with detailed design work starting this year
and development completion targeted for 2028.

Provides not only electricity but also heat and steam,
playing a key role in achieving carbon neutrality in industrial sites.

Director Han-gon Kim, Head of the Innovative SMR Technology Development Project Team

"The innovative Small Modular Reactor (i-SMR) being developed by Korea is a nuclear power plant that satisfies both safety and economic efficiency. It can be considered the closest to commercialization among competitors."

Kim Han-gon, head of the Innovative SMR Technology Development Project Group, whom we recently met, expressed confidence in Korea's SMR technology and its potential for success. It is understood that there are about 90 types of small modular reactors being developed worldwide. Among them, only a few designs can be commercialized within the next 10 years. Kim emphasized that the i-SMR is the closest to commercialization among these.

Kim explained that SMRs are designed with no piping and a passive system that can continue operating even during power outages, making the accident probability only one-thousandth that of conventional large nuclear power plants. In other words, the risk of accidents is virtually nonexistent.

The key to SMR commercialization is achieving economic feasibility. Even advanced nuclear power countries like the United States have not yet commercialized SMRs because they have not solved this issue. The i-SMR plans to address economic feasibility by manufacturing modules in factories and completing construction within 24 months.

SMRs are evaluated as a key means for carbon neutrality, not only because they produce electrical energy but also because they can supply heat and steam needed in industrial sites. Kim hopes that the government will include SMRs in the 11th Basic Plan for Electricity Supply and Demand (Jeon-gi-bon) to be established this year. To achieve the goal of completing the first SMR by 2031, SMRs must be included in the plan so that technology development and site selection can proceed simultaneously.

Kim, a former director of the Korea Hydro & Nuclear Power Central Research Institute, was appointed head of the i-SMR Technology Development Project Group in January last year. The project group was launched last year to promote the i-SMR technology development project led by the Ministry of Science and ICT and the Ministry of Trade, Industry and Energy.

Kim earned his bachelor's degree in Nuclear Engineering from Seoul National University and his master's and doctorate degrees in Nuclear Engineering from KAIST. Since 1997, he has worked at the KHNP Central Research Institute, participating in the development of the APR1400 and is recognized as an expert in domestic reactor development, design, and licensing.

Below is a Q&A with Kim.

- How does Korea's i-SMR differ from those being developed overseas?

▲ There are currently about 90 types of SMRs being developed worldwide. Not all of these will be commercialized immediately. Many are being developed with a 20 to 30-year horizon. For example, TerraPower in the U.S., invested in by Bill Gates, is developing a sodium reactor and is currently discussing demonstration. Commercialization will take a very long time. Among light-water reactors that can be commercialized within 10 years, there are only a few, including Korea's i-SMR, the U.S.'s NuScale, BWRX-300 (GE-Hitachi), and Nuward (France's EDF).

- What are the strengths of the i-SMR?

▲ To commercialize SMRs, two main conditions must be met. First, it must be safe; second, it must be economical. Few meet both conditions. Korea demonstrated it can build nuclear power plants on schedule through the successful UAE project. Competitors lack this experience. Few have the capability to build SMRs that are both safe and economical. Korea's i-SMR is closest to meeting these conditions.

- How does it compare to the U.S.'s NuScale?

▲ NuScale is considered the most advanced in the U.S. While development may have started earlier than ours, it is a venture company with no actual commercialization experience. Korea's KHNP and Korea Atomic Energy Research Institute, which have successfully built large nuclear power plants, are directly involved in development, and the government is actively supporting it. This is why overseas also believe Korea can succeed in developing SMRs.

- What is the level of Korea's SMR technology?

▲ Compared to competitors like the U.S., Russia, and France, Korea's technology is on par. Although the U.S., which started nuclear power first, holds many original technologies, these transferred to France in the 1960s, and since the 1980s, Korea has been leading. Decades have passed, so there is little difference in technology itself. However, Korea is evaluated to have fewer trial-and-error experiences because of its successful nuclear power plant construction experience.

- Why is SMR commercialization difficult?

▲ Commercializing SMRs is said to take 10 years. First, a site must be selected. Then, it takes 2 to 3 years to evaluate site suitability. Construction alone takes 4 to 5 years. Unlike cars or smartphones, products do not come out immediately after development. Korea has basic technology from decades of nuclear operation experience. Core technologies for miniaturization and modularization must be added. Detailed design will start this year and be completed by 2028.

- How do you evaluate SMRs developed by Russia and China?

▲ Russia has developed the KLT40S marine floating SMR supplying power to the Arctic wilderness. China is building the ACP100 small reactor in the Hainan Changjiang area. These small reactors are government-led and do not consider economic feasibility at all. They may claim to be the first SMRs, but this is hard to accept. Commercial SMRs must have both safety and economic feasibility.

- Are SMRs really safe?

▲ SMRs greatly reduce the possibility of accidents compared to large nuclear plants. The accident probability is only one-thousandth that of third-generation reactors. SMRs have no piping, so accidents caused by pipe breaks do not occur. They are designed with passive systems (natural circulation systems that maintain reactor cooling even if power is cut), allowing safe operation during blackouts. Passive systems have been continuously developed over the past decade and are ready for application. Experts like us believe there is no technical possibility of accidents like Fukushima. However, how residents accept this is another matter. We believe that with good promotion, residents will accept it.

- There are criticisms that SMRs lack economic feasibility.

▲ Opponents claim "SMR economic feasibility is a myth." It is true that building a power plant with a capacity of 1 million kilowatts (kW) is more economical than building one with 100,000 kW capacity. SMRs have not been commercialized so far because economic feasibility has not been solved. The key is to make them small but economical. To achieve SMR economic feasibility, construction time must be shortened to reduce construction and interest costs. We aim to reduce construction time to 24 months by manufacturing reactors in factories and transporting them to the site for installation. The second is to reduce components. Achieving these two will realize economic feasibility. It is indeed a challenging task.

- Is there anything the government or regulatory agencies can do to help?

▲ Current regulatory requirements are tailored to large commercial nuclear plants. It is necessary to revise regulations to enhance safety while accommodating SMR's innovative technologies. I understand that the Nuclear Safety and Security Commission is currently establishing regulatory directions on this.

- How can SMRs be utilized?

▲ SMRs are not only needed for power generation. They are gaining attention because they can play a key role in achieving carbon neutrality by 2050. To achieve carbon neutrality, both electrical energy and thermal energy used in homes and industries must be converted to zero carbon. Renewable energy alone is insufficient. All possible means must be mobilized. For example, hydrogen needed for hydrogen reduction steelmaking can be produced using nuclear hydrogen from SMRs. Heat and steam needed in chemical plants can also be supplied by SMRs. SMRs are also a good means to complement the intermittency of renewable energies like solar and wind.

- Including SMRs in the 11th Basic Plan for Electricity Supply and Demand is an issue. What is your view?

▲ To complete design by 2028 and commission the first unit by 2031 as planned, I believe SMRs should be included in this year's Basic Plan for Electricity Supply and Demand. Of course, there may be controversy about including SMRs, which are not yet fully developed, in the plan. But if they are included in the next plan two years later, the schedule will be delayed. We only express our opinion; the final decision rests with the government.

- Will introducing SMRs eliminate the need for large nuclear power plants?

▲ Absolutely not. SMRs and large nuclear plants serve different markets. Large nuclear plants are built where large amounts of electricity are needed. In areas subject to the Distributed Energy Activation Special Act (Distributed Energy Act), SMRs will replace large nuclear plants. SMRs are also needed to replace aging coal-fired power plants.

◆ Small Modular Reactor (SMR)

This term generally refers to nuclear power plants designed with smaller unit capacity and modular construction compared to large nuclear plants. Typically, it means reactors with a capacity of 300 megawatts electric (MWe) or less. They have advantages such as easier construction and versatile applications compared to large nuclear plants.

They feature integration of the steam generator, pump, pressurizer, and core (the part producing heat through nuclear fission) into a single vessel, reducing the possibility of radioactive leakage caused by pipe breaks. A passive safety concept is applied, allowing reactor cooling using natural forces even if external power is cut.

Because of enhanced safety and the ability to be built on smaller sites than large nuclear plants, they can be located near demand centers. They are designed for multipurpose use, including power generation, hydrogen production, process heat utilization, district heating, and marine exploration.

SMRs are classified into third-generation, which apply existing commercial technologies, and fourth-generation, which apply next-generation technologies such as high-temperature gas reactors, sodium (Na) fast reactors, and molten salt reactors. According to the International Atomic Energy Agency (IAEA), as of 2022, more than 80 types of small reactors are being developed and constructed worldwide, including 21 in the U.S., 17 in Russia, 10 in China, 5 in Canada, and 4 in the U.K.

The Idaho National Laboratory under the U.S. Department of Energy forecasts that 50% of new nuclear plants by 2050 will be SMRs. Korea's i-SMR Technology Development Project Group aims to complete design by 2028.

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