Nuclear power programme

Prelims and Mains

Stage 1 is the fleet India actually operates, and it runs on uranium as it comes out of the ground. Almost everything now under construction is the same design in a larger version.

• A pressurised heavy water reactor (PHWR) is the Stage 1 design, fuelled by natural uranium with heavy water as both moderator and coolant.
• Ten 700 MW PHWRs are to take installed nuclear capacity to about 22,480 MW by 2031-32.
• Design changes after Fukushima, late Russian supplies at Kudankulam and difficult soil at Gorakhpur held the expansion up for decades.

Prelims and Mains

Stage 2 opened at Kalpakkam in April 2026, about two decades after it was meant to, with a reactor India built almost entirely itself. Its engineering difficulty is its coolant: liquid sodium carries heat superbly and is completely opaque, so the machine cannot be inspected by eye.

• The Prototype Fast Breeder Reactor (PFBR) reached first criticality on 6 April 2026, confirmed in a Rajya Sabha reply in August.
• It runs on MOX fuel and is cooled by liquid sodium.
• Its blanket of uranium-238 absorbs neutrons and becomes fissile plutonium-239.
• About 90 per cent Indian built, it was commissioned with a robot and ultrasonic imaging that see through the sodium.

Prelims and Mains

A small modular reactor is built in a factory and assembled on site, which is meant to take years and capital out of a technology that has been short of neither. India is designing three at once, and they are not variations on one another.

• The Prime Minister said five indigenous SMRs will be running by 2033.
• BSMR-200 of 220 MWe and SMR-55 of 55 MWe are pressurised water reactors for Tarapur.
• A high temperature gas cooled reactor of up to 5 MWth at BARC Visakhapatnam is to make hydrogen by the copper-chlorine cycle.

Prelims and Mains

The law that let private companies into nuclear power also settled who pays if a plant fails, and that second half of it is now before the Supreme Court. A cap on liability is what makes the risk insurable, which is the argument for it and, to the petitioners, the argument against.

• The Sustainable Harnessing and Advancement of Nuclear Energy for Transforming India (SHANTI) Act, 2025, notified on 21 December 2025, lets private companies into nuclear power under licence.
• The same Act gave the Atomic Energy Regulatory Board (AERB) statutory status and set graded liability in line with international conventions.
• It caps the government's residual liability at 300 million Special Drawing Rights and an operator's at ₹3,000 crore, and exempts equipment suppliers altogether.
• The Supreme Court issued notice to the Centre and the AERB on a challenge to the caps.
• It asked whether a statutory cap can stop a constitutional court awarding victims fair compensation.
• Petitioners set the caps against the estimated costs of Chernobyl and Fukushima.

Prelims and Mains

Everything above is aimed at a single number, and it is more than ten times the capacity running today. Two decades is not long for a technology whose last expansion slipped by that much.

• The Nuclear Energy Mission sets a target of 100 GWe by 2047.
• About half of that is expected from indigenous PHWRs, a fleet heading towards 50 to 60 GW.
• Reaching it needs private and foreign capital, which is why the liability terms decide the pace.