Fast Breeder Reactor Attains Criticality, Gives India Nuclear Freedom

Criticality means the start of controlled fission chain reaction: In the PFBR, it means producing more nuclear fuel and electric power. The PFBR runs on a mix of Plutonium-239 (the ‘fire) and Uranium-238 (‘the breeding ground’). This mix fires atomic particle (neutrons) at a ‘blanket’ of Thorium-232, converting it into Uranium-233 that can be used for Stage 3 nuclear reactors. Several countries including the US and China have failed to achieve this so far.

“It is a decisive step towards harnessing our vast thorium reserves in the third stage of the programme,” Modi posted on his X handle, congratulating scientists and engineers.

The fast breeder reactor (FBR) is the cornerstone on which India’s nuclear energy policy rests. It is part of the three-stage nuclear programme laid out by Homi J. Bhabha in 1954, which seeks to overcome lack of uranium reserves in the country by harnessing abundant thorium reserves. India, according to an estimate, has one-fourth of the world’s thorium reserves.

As per the department of atomic energy (DAE), the technology development and design of PFBR was indigenously done by the Indira Gandhi Centre for Atomic Research.

Anil Kakodkar, former secretary of the DAE, said that the “historic” development was very important from the point of view of India's energy security. In view of India's dependency on other countries for fossil fuels, the move assumes significance, especially at a time when the crisis in West Asia has impacted the supply of oil and natural gas, he said.

Unlike other nuclear reactors, the fast breeder reactor not only produces energy but also produces fuel, Kakodkar said. This is why it is called a 'breeder reactor', he added.

According to the DAE, the PFBR uses Uranium-Plutonium Mixed Oxide (MOX) fuel. The core of PFBR is surrounded by a blanket of Uranium-238. Fast neutrons convert fertile Uranium-238 into fissile Plutonium-239, enabling the reactor to produce more fuel than it consumes. The reactor is designed to eventually use Thorium-232 in the blanket. Through transmutation, Thorium-232 will be converted into Uranium-233, which will fuel the third stage of India's nuclear power programme.

K.N. Vyas, former secretary of the DAE, said the development was significant as the technology involved is very advanced. However, the reactor will not start producing electricity immediately and will undergo a variety of tests, he said.

Countries like France and the US were unable to scale up their breeder reactors, Vyas said.

Concurring with Vyas, Kakodkar said that after Russia, which is the only country to run two breeder reactors with a capacity of 600 MW and 800 MW, India is the only country to develop a reactor with a capacity of 500 MW. France and the US operate breeder reactors but not at this scale, he said.

Rajeshwari Rajagopalan, resident senior fellow at Australian Strategic Policy Institute, Canberra, said the development was impressive despite the huge delays.

Kakodkar said that as in the case of pressurised heavy water reactors technology, which Indian scientists have mastered over decades and ramped up the construction of nuclear plants, the next step will be to make the Fast Breeder Reactor technology more robust and scale up the reactors.

In a written reply in the Rajya Sabha last month, Jitendra Singh, minister of state in the Prime Minister's Office, had said that the government had accorded approval to carry out pre-project activities for 2 x 500 MWe twin unit of FBR 1&2 project at Kalpakkam, Tamil Nadu.

On attaining first criticality of PFBR, the government will be approached for financial sanction of FBR 1 and 2 projects, Singh had said.