President Vladimir Putin claims Russia has made a nuclear technology breakthrough and has developed a closed fuel cycle power system to tackle global uranium shortages.

He said Russia is moving forward with the development of its first industrial-scale closed fuel cycle reactor, the BREST-OD-300, which would be a gamechanger if the claims are confirmed.

In parallel, China has also claimed to have made several significant advances in nuclear technology in the last year, claiming to have developed the first fusion reactor that produces more energy than it consumes, and a molten salt and high-temperature gas-cooled reactors that don’t need uranium or any other radioactive material as a fuel.

Installation work began for the condenser in the turbine hall for the BREST-OD-300 lead-cooled fast neutron reactor at the Siberian Chemical Combine site in Seversk, in the Tomsk Region of Russia in November. 

Russia's state nuclear corporation Rosatom says it will enable more efficient use of uranium resources and reduce long-lived radioactive waste. The fast neutron reactor is currently under construction in Seversk, Siberia, with commissioning expected by the end of the decade.

A closed fuel cycle reactor is a fuel management strategy, not a specific reactor type. Spent nuclear fuel is reprocessed and reused, rather than being treated as waste after one use, as in an open fuel cycle. The BREST-OD-300 recycles fuel on-site, enabling continuous reuse of uranium and plutonium. The reactor is similar to a fast breeder reactor that uses fast neutrons, unlike conventional reactors, and is specifically designed to "breed" more fissile material than it consumes.

The project, part of Russia’s Proryv (Breakthrough) programme potentially could allow uranium to be utilised for thousands of years.

“A closed-cycle reactor is the holy grail of nuclear energy,” said Alexey Anpilogov, an energy expert, in an interview with Russia’s state owned news agency Sputnik. “Scientists have pursued it since the dawn of the nuclear age.”

Unlike conventional light-water reactors, which Russia currently specialises in and uses less than 1% of the uranium in nuclear fuel, BREST-OD-300 is designed to use uranium-238 — a more abundant isotope — and convert it into fissile plutonium-239. During operation, the reactor can also consume long-lived radioactive elements such as caesium and strontium, which have been caused widespread and long-lasting environmental contamination in the Chernobyl disaster.

According to Rosatom, the lead-cooled BREST reactor will operate with an integrated on-site fuel reprocessing system, allowing spent fuel to be recycled without the need for external transport. The project is viewed as a strategic step toward improving nuclear sustainability, although questions remain about its economic viability and proliferation risks.

Alexander Uvarov, director of AtomInfo-Center, said the reactor is on track for commissioning by 2030. “The Russian president set 2030 as the launch date for the system, but I’d say it will start even earlier,” he told Sputnik.

However, Putin’s claim that Russia uses this technology is disputed. While the BREST-OD-300 may be the first to enter industrial development, several other countries also have active fast reactor programmes.

China is constructing a 600 MW sodium-cooled fast reactor in Fujian province, with completion expected in the late 2020s. The US and Japan, both pioneers in fast reactor technology, have paused or scaled back projects due to cost and safety concerns but maintain active research in the area.

The World Nuclear Association notes that fast reactors are technologically complex and expensive, with none yet proven at commercial scale. Critics also point to significant hurdles in fuel reprocessing and waste management. The International Atomic Energy Agency (IAEA) has acknowledged the potential of closed fuel cycles but cautions that implementation requires “robust safeguards and regulatory frameworks.”

Russia has positioned the new reactor type as a potential export offering, particularly to BRICS nations. Rosatom is currently in talks with Iran to build a second nuclear reactor in that country and Russian nuclear exports are booming, based on its third generation VVER 1200 (water-water energetic reactor) that are compliant with the IAEA’s International Nuclear Safety Group (INSAG) recommendations and general considered to be safe.

“Rosatom actively cooperates with India and China, both of which have huge plans for nuclear energy,” Uvarov said. “Export prospects look very promising.” However, it remains unclear whether these countries would adopt a system still in early industrial demonstration.

Independent experts stress that full commercial viability may still be years away. “If you load 1 kg of uranium into such a reactor, you’ll not only get electricity and heat, but also produce more than 1 kg of new plutonium,” Anpilogov said. “It’s like a magic wallet where the money grows on its own.” The analogy overlooks the regulatory and technical complexities still facing developing commercially viable closed fuel cycle systems.

The BREST-OD-300’s construction began in 2021. If successful, it would mark the first time a Generation IV reactor design with a closed fuel cycle has been deployed beyond the experimental stage.

Chinese nuclear progress

Sanctions, the ongoing green revolution and the East-West clash have spurred both Russia and China to accelerate their technology and are driving technological innovation in both countries. Nuclear power tech has emerged as a key battleground and also a new geopolitical tool that Beijing and Moscow are using to tie other members of the Global South into their orbit. For Russia, uranium is the new gas.

China, in particular, has made significant strides in nuclear innovation. The China National Nuclear Corporation (CNNC) is developing the CFR-600, a 600 MW sodium-cooled fast reactor located in Xiapu, Fujian province. Construction of the first unit began in 2017, with completion now expected by 2026. The reactor is part of China’s broader strategy to close the nuclear fuel cycle and reduce dependence on uranium imports.

In parallel, China is advancing work on molten salt and high-temperature gas-cooled reactors. In 2021, it launched the world’s first thorium-based molten salt experimental reactor in Wuwei, Gansu province. The high-temperature gas-cooled reactor (HTR-PM), developed by Tsinghua University and CNNC, connected to the grid in 2021 and is regarded by the IAEA as a milestone for fourth-generation nuclear designs.

According to the World Nuclear Association, China currently operates more than 50 nuclear reactors and has over 20 under construction — the largest build-out programme globally. Its long-term energy plan envisions up to 150 new reactors by 2050, making it the most ambitious national programme in the world.

China has also made progress in fuel recycling and spent fuel reprocessing. A pilot reprocessing plant in Gansu province has been operating since 2010, and plans are underway for a commercial-scale facility with support from China National Nuclear Power (CNNP) and the China Institute of Atomic Energy.

Last year, China's Energy Singularity reported that it has produced a working fusion reactor that can create net energy positive fusion reactions. China also reported that it has built a melt-down proof nuclear reactor that uses uranium “pebbles” that will cool itself if the power is cut off, without the need of additional cooling.

Fourth-generation nuclear reactors represent the next frontier in nuclear technology, promising greater efficiency, enhanced safety features and China is currently on track to overtake both the US and France in the coming years.