[AI Era Electric Power is National Power] ⑤ "Local Governments Also Line Up"... Visiting the Development Site of 'AI Customized' SMR

KHNP Central Research Institute SMR Control Center
Continuous Visits from Local Governments Seeking Data Centers
Kim Han-gon, Head of i-SMR Technology Development Project
"Standard Design to Be Completed Within This Year"
KAERI: "i-SMR Experimental Device Ordered"

"Local governments wishing to attract artificial intelligence (AI) data centers are showing great interest in small modular reactors (SMRs)."

On the 17th of last month, I visited the Korea Hydro & Nuclear Power Central Research Institute in Yuseong-gu, Daejeon. Upon entering the 'SMR Smart Net Zero City (SSNC) Integrated Control Center' set up inside the institute, a simulator that replicates the SMR central control room was immediately noticeable. This space was established by KHNP to explain how SMRs, along with solar and wind power, can be used to create eco-friendly cities.

Lee Sang-hoon, deputy director of KHNP's Central Research Institute, whom I met there, explained, "Since the integrated completion last August, visits from local governments and various research institutions have been continuous." He added that local governments aiming to attract AI data centers, which are expected to consume massive amounts of electricity, are particularly showing high interest.

Interior view of the Korea Hydro & Nuclear Power SSNC Integrated Control Center. Provided by Korea Hydro & Nuclear Power

According to simulations conducted by KHNP, if 80% of Korea's innovative small modular reactors (i-SMR) under development are used together with 20% renewable energy, it can save 20-30% more energy compared to a combination of 80% coal and 20% renewable energy. Unlike conventional large nuclear power plants, i-SMRs can operate with load-following capability (adjusting generator output according to power demand), allowing them to be used alongside renewable energy. KHNP expects output adjustment within 5%.

"1000 Times Safer Than Existing Large Nuclear Plants... No Need for Resident Evacuation"

The i-SMR is a next-generation SMR jointly promoted as a national project by the Ministry of Science and ICT and the Ministry of Trade, Industry and Energy. The number of participating institutions and companies in this project reaches 44. The goal is to complete the standard design by this year and finish the Nuclear Safety and Security Commission's (NSSC) standard design review between 2026 and 2028. Kim Han-gon, head of the i-SMR technology development project group, told Asia Economy in an interview, "We expect to complete the standard design within this year as planned." The i-SMR project group is conducting preliminary discussions with the NSSC for standard design approval.

Kim Han-gon, Director of the Innovative SMR Technology Development Project Group.

SMRs refer to small reactors with a capacity of 300 megawatts (MW) or less. Large nuclear power plants installed domestically have capacities exceeding 1000 MW. SMRs are not just smaller in size but are characterized by enhanced safety and modular construction, significantly shortening construction periods.

Before the currently developing i-SMR, Korea had already received standard design approval for small modular reactors named 'SMART' and 'SMART100.' These reactors, like conventional large nuclear plants, installed the core, pressurizer, steam generator, and coolant pumps separately inside the containment building.

In contrast, the i-SMR is designed as an integrated unit that consolidates major equipment within a single steel vessel. This significantly reduces the reactor's size. The total height of the i-SMR reactor is only 35 meters. The prefix "innovative" is attached because its concept differs from existing nuclear plants.

Since i-SMR applies different technologies and concepts from the start, current safety regulations cannot be directly applied. According to the project group, there are 36 existing regulations incompatible with the i-SMR design.

For example, large nuclear plants assume one reactor constitutes one power plant and regulate the number of operators accordingly. However, SMRs can have multiple reactors within one power plant. The i-SMR connects four 170 MW reactors side by side. Following existing regulations would require staffing equivalent to four nuclear plants.

Existing regulations that set a radiation emergency planning zone (EPZ) within 20-30 km around nuclear plants to prepare resident protection measures in case of radiation leaks will likely need revision. Since SMRs have smaller capacity and significantly lower accident probability than large nuclear plants, such regulations are unnecessary.

Kim Han-gon stated, "SMRs have an accident probability less than one-thousandth that of large nuclear plants, so there is no need for resident evacuation," adding, "The U.S. Nuclear Regulatory Commission (NRC) has already revised its regulations so that if the probability of radioactive leakage is less than once in a billion years, an EPZ does not need to be established."

i-SMRs are safer than existing reactors not only because of their smaller capacity but also due to multiple safety features. Notably, i-SMRs adopt passive safety systems that prevent radioactive leakage even in disaster situations like the Fukushima nuclear accident. The Fukushima accident was caused by the cooling pump being submerged and failing due to an earthquake and tsunami, leading to core meltdown. However, the passive safety system cools the core through natural convection without external power.

The passive safety system has already been applied to the SMART reactor, which has received design certification, and its safety has been verified through the ATLAS experiments conducted by the Korea Atomic Energy Research Institute (KAERI).

ATLAS, established by KAERI, is an experimental facility that comprehensively simulates the cooling performance of reactor systems under actual pressure and temperature conditions for major accidents in pressurized water reactors. During a visit to KAERI's Nuclear Safety Research Institute, I saw the ATLAS experimental device scaled down to 1/280 of the actual size (by volume) of the APR1400 reactor. This device uses a boiler generating heat equivalent to the APR1400 reactor to verify the operation of various safety systems.

A representative from the Korea Atomic Energy Research Institute is inspecting the 'ATLAS' experimental device. Photo by Korea Atomic Energy Research Institute

KAERI plans to verify the safety of the i-SMR through similar experiments following those for the APR1400 and SMART reactors. Bae Byung-eon, senior researcher (Ph.D.) at KAERI, said, "We have started ordering the fabrication of the i-SMR integrated effect experimental device," adding, "We plan to prepare thoroughly to avoid any delays in the standard design review."

"Who Builds First?"... Global Competition in the AI Era

The characteristics of SMRs, which are safer than large nuclear plants and can be installed near demand sites, are evaluated as optimal solutions for AI data centers. SMRs can be constructed on relatively small land areas. Large nuclear plants face difficulties in securing sites and establishing power grids to demand sites, often encountering resident opposition.

The appearance of i-SMR power plants is completely different from existing large nuclear plants. They do not require massive chimneys or concrete containment buildings. KHNP is considering installing i-SMRs 50 meters underground. To avoid discomfort among residents, only minimal buildings will be exposed above ground.

In the U.S., plans are being considered to close coal-fired power plants that emit large amounts of carbon and reuse those sites for SMRs. This approach eliminates the need to find new sites and allows existing power grids to be utilized.

One major argument from SMR opponents is the lack of economic feasibility. According to the economies of scale principle, the larger the power plant, the lower the cost per unit of electricity produced. Since SMRs are small, their levelized cost of electricity (LCOE) tends to be higher. In fact, U.S.-based NuScale Power canceled its plan to build an SMR in Utah in 2023 due to rising costs.

Regarding this, Kim Han-gon emphasized, "For the first-of-a-kind unit, economic feasibility is inevitably lacking," adding, "However, as experience accumulates, construction costs will significantly decrease." He explained that i-SMRs are manufactured in factories and transported by truck for on-site installation, so costs will drop substantially as production volume increases. Also, unlike large nuclear plants that take over six years to build, SMRs can be constructed within two years, enabling significant cost reductions if the plan proceeds as scheduled.

It should not be overlooked that countries currently developing SMRs prioritize who will successfully build the first commercial SMR over economic feasibility. Success in commercial SMR construction allows them to secure the expanding SMR market in the future.

Currently, the most advanced player globally is NuScale Power in the U.S. Like the i-SMR, NuScale Power's design is a pressurized water reactor and integrated type. The company is currently working on a project to install six 77 MW SMRs in Romania. The U.S. government is providing substantial support, including $4 billion (approximately 5.7 trillion KRW) in financing.

SMRs classified as fourth-generation, such as TerraPower (sodium-cooled fast reactor) invested in by Bill Gates, Kairos (molten salt reactor) invested in by Google, and X-energy (high-temperature gas reactor) invested in Amazon, are still considered far from commercialization.

Korea aims to complete the i-SMR standard design review by 2028, select a site, and construct the first unit by the mid-2030s. The 11th Basic Plan for Electricity Supply and Demand targets the preliminary completion of one module by September 2034 and the full completion of four modules by 2035.

Unlike NuScale Power, i-SMR enhances competitiveness with a boron-free design. This means output can be controlled solely by control rods without boron. This prevents equipment corrosion caused by boron and reduces the number of devices and components. It also decreases the amount of spent nuclear fuel generated.

Korea is also taking thorough measures against potential patent disputes. Kim Han-gon explained, "We have filed about 150 patents independently," adding, "Through meticulous patent analysis, we are ensuring no disputes arise with NuScale Power."