New Delhi: China has created history. It has not only built the world’s first 2-megawatt liquid-fuelled thorium molten salt reactor, but has also successfully transformed thorium into usable nuclear fuel, a feat that India has been attempting for years but is yet to achieve.
China’s Shanghai Institute of Applied Physics of the Chinese Academy of Sciences announced on 1 November that TMSR-LF1 achieved the first conversion of thorium and uranium nuclear fuel.
“This marks the first time international experimental data has been obtained after thorium was introduced into a molten salt reactor, making it the only operational molten salt reactor in the world to have successfully incorporated thorium fuel,” the institute said.
While China has seized the opportunity to utilise its thorium, India is dragging its feet despite having one of the world’s largest reserves.
Officials from the DAE (Department of Atomic Energy) told ThePrint that India’s progress in the field of nuclear energy should not be guided by work in China or any other country.
“India has its own journey and challenges. We must take lessons from our neighbours, but we must not base our progress on theirs. Our nuclear programme is unique,” the DAE official said.
Nuclear scientist and former chairperson of the Atomic Energy Commission, Anil Kakodkar said that India should have achieved the feat of transforming thorium into usable nuclear fuel before China, but this is a significant development for the world.
“This is definitely an important development. Thorium utilisation has also been the target of India’s nuclear energy programme. Such an achievement is not just important for a nation, but it provides an opportunity to become the energy provider for the world,” Kakodkar told ThePrint.
For years, India has been betting on thorium to power nuclear reactors, confident of the country’s rich thorium reserves. Government data shows that India has around 11.93 million tonnes of in situ monazite reserves—a thorium-bearing mineral—which contain about 1.07 million tonnes of thorium.
In fact, India’s three-stage nuclear programme, set up by scientist Homi J. Bhabha in the 1950s, also had the ultimate goal of utilising thorium in nuclear reactors.
Last month, the fuel-loading process began at India’s most advanced and complex nuclear reactor, the Prototype Fast Breeder Reactor (PFBR) in Tamil Nadu’s Kalpakkam. The PFBR, which is aiming to be operational by the end of 2026, is a 500 MW liquid sodium-cooled reactor designed to use plutonium as fuel. However, this technology can also use thorium.
Since thorium is fertile, not fissile, it cannot be used directly in a nuclear reactor. It needs to be converted to the fissile isotope Uranium-233 within a reactor. This conversion process happens when the fertile element, Thorium-232, absorbs neutrons to transform into Thorium-233. This then decays into Protactinium-233 and finally into the fissile Uranium-233.
In emerging technologies like the molten salt reactors, Uranium-233 is used as fuel in conjunction with a fissile driver like plutonium.
India’s thorium reserves
A 2004 analysis by Mumbai’s Bhabha Atomic Research Centre highlighted that India’s thorium reserves would be enough to generate “358,000 GWe-yr of electrical energy and can easily meet the energy requirements during the next century and beyond”.
A majority of these reserves have been identified around Kerala, Tamil Nadu, Odisha and Andhra Pradesh. These are regions that are rich in monazite reserves, from which thorium is extracted.
The government’s Department of Atomic Energy and the Atomic Minerals Directorate have highlighted that Tamil Nadu’s Kanyakumari-Manavalakurichi belt—near Ram Setu—is one of India’s richest monazite placer deposits.
In recent years, China has claimed to have identified additional thorium reserves. Latest reports suggest that the country’s identified thorium resources total around 1.3–1.4 million tonnes, compared to India’s 1.07 million tonnes.
India’s slow-moving nuclear programme
In the last 70 years, since India launched its nuclear programme, India has set up around 20 pressurised heavy-water reactors (PHWR). Its PFBR is also slated to be operational by 2026.
The PHWR—which is essentially a converter reactor—uses heavy water as coolant and moderator, and runs on natural uranium. PFBR, on the other hand, is a fast reactor that uses liquid sodium as coolant and does not need a moderator. It is designed to breed more fissile material than it consumes.
Indian agencies are also experimenting with Advanced Heavy Water reactors (AHWR). These reactors are heavy-water-moderated, light-water-cooled and use a thorium-based fuel cycle to produce electricity. Its design incorporates advanced safety features, including passive systems for heat removal and emergency cooling.
Experts said that it is time for India to start experimenting with different reactor designs to make its programme more efficient.
“Learning from China’s success with the molten salt reactor, India should look beyond heavy water reactors and experiment with different reactor designs. This not only includes molten salt but also accelerator-driven systems and high-temperature gas-cooled reactor design,” said Lokendra Sharma, a research analyst with the High-Tech Geopolitics Programme at the Takshashila Institution.
Sharma said that as much as India’s three-stage plan was aimed at securing weapons-grade plutonium for its strategic programme, it has largely served its purpose. Even after decades, the ultimate objective of the plan—exploiting thorium for generating potentially limitless energy—remains unfulfilled, he said.
“It is time the Indian nuclear establishment adopts realistic direct thorium utilisation plans in parallel to the long-term three-stage plan,” he added.
China takes the lead
Construction of China’s TMSR-LF1 reactor began in September 2018, with the initial plan to complete it by 2024. However, work was completed by August 2021.
Between 2013 and 2024, China built 13 reactors and is planning to build another 33. While a lot of its existing reactors borrow technology from the US and France, it is also independently investing a lot of money in experimental technology related to nuclear energy.
In the process, their focus is also to bring down the cost of developing these reactors significantly.
A study published in the science journal Nature in July this year by scientists from Harvard University, City University of New York and Johns Hopkins University, showed that the cost of constructing nuclear reactors in the US started rising after the 1960s. However, in China, the cost fell by half in the 2000s.
For instance, the US’ Vogtle 4 reactor, the construction for which began in 2013 and was made operational last year, with a capacity of 1,250 MW, came up to cost $15 per watt. China’s Fangchenggang 4, with a capacity of 1,180 MW, started operating in March 2024. Its cost per watt comes to only about $1.97—significantly lower than in the US.
(Edited by Viny Mishra)
Also read: Fast breeder reactor gives India a strategic edge—and a step closer to nuclear self-reliance