India’s Native Fast Breeder Reactor Reaches First Criticality: 5 Things to Know

What is a fast breeder reactor: The country's indigenously designed and built Prototype Fast Breeder Reactor (PFBR) is located at Kalpakkam in Tamil Nadu. A fast breeder reactor is a type of nuclear reactor that is designed to produce more fissile material than it consumes while generating electricity. It is different from thermal reactors that use fast neutrons to sustain the nuclear fission chain reaction.

What is first criticality: In a nuclear journey, when a reactor core is brought to a self-sustaining state is called first criticality. Put simply, this is the stage where a reactor's fission produces the same number of neutrons that are lost in generating energy. The stage provides both operational validation and safety clearance to move forward to the next stage.

PFBR overview: Developed by the Indira Gandhi Centre for Atomic Research (IGCAR), the PFBR uses Uranium-Plutonium Mixed Oxide (MOX) fuel. With liquid sodium as the coolant, the reactor is able to operate at high temperature without causing any operational issues. It is also called a closed fuel cycle since the spent fuel generated by the reactor is reprocessed and recycled.

India's nuclear energy landscape: Over the years, the country's nuclear programme has steadily contributed to the energy needs, powering 8.78GW of energy. Last year, indigenous nuclear power plants generated 56,681 million units of electricity, with a total share of 3.1 percent. With 700MW and 1,000MW reactors under development, the nuclear energy contribution is expected to reach 22.38GW by the end of 2032.

Long-term mission: In the Union Budget 2025-26, the Government has outlined the aim of reaching 100GW of nuclear power generation capacity by 2047. To drive it forward, the Nuclear Energy Mission has allocated Rs. 20,000 crore to design, develop, and operationalise Small Modular Reactors (SMRs). At least five such reactors are expected to be running by 2033.