Accelerating Nuclear Programme Requires Clarity and Decisive Action, Says Former BARC Director KN Vyas

The BSR design has already been approved by the regulator, with over 95% of its components made in India. It is a very good idea, as the 220MW reactor will help private entities understand the complexities and safety requirements typical of nuclear projects. In comparison, the BSMR design still needs to be evolved and approved, which could take another three to four years before construction can begin, delaying project initiation.

Two BSRs were made operational at the Narora Atomic Power Station in the early 1990s, marking the beginning of indigenous PHWR [pressurised heavy water reactor] development—originally based on Canadian technology and now successfully implemented at Kakrapar, Kaiga and Rajasthan. This makes a total of 12 BSRs for which NPCIL [Nuclear Power Corporation of India] has extensive experience in design, construction and operation. Starting with the BSR is more appropriate since work can begin immediately, whereas waiting for the BSMR would delay private sector involvement and slow progress towards the target.

Shifting to thorium is essential but comes with challenges. Thorium alone cannot sustain a nuclear chain reaction; it is more of a burden on the reactor. It should therefore be mixed with about 10% enriched uranium, which will require importing this material. Kudankulam-type reactors use approximately 4.5% enriched uranium, while PHWRs use natural uranium with 0.7% enrichment. In comparison, thorium use demands higher enrichment. When mixed with thorium oxide, the enriched uranium oxide burns first, converting thorium into a fissile uranium isotope that later generates power. PHWRs are best suited for the uranium–thorium mixed oxide fuel.

The design and technology already exist, but two key issues remain: securing enriched uranium supplies and deciding how to handle spent fuel. Large-scale adoption will also depend on the number of reactors, as developing new thorium-based fuel will be economically viable only if enough reactors can use it. India has the necessary theoretical base and experimental capability, but practical progress depends on clear policy direction and industry willingness to adopt thorium fuel. The decision to adopt this option or otherwise should be taken soon.

It can be used in any fission reactor, but depending on the design of the particular reactor, uranium with an appropriate level of enrichment may have to be used. As a rule, using thorium places a burden on reactivity.

NTPC has access to much larger resources because it owns and operates a large number of thermal power stations. It has basic capabilities but needs to learn the discipline of the technology from NPCIL before it can take over independently. In my opinion, it is not difficult to learn.

For PHWRs, more than 90% of the components are made in India. Only certain items—mainly raw materials such as steel forgings or plates, which are expensive to produce locally—are imported. For the Narora-type reactors, all components are manufactured in India.

The AERB is a competent regulator, but if multiple private entities propose several new reactor designs, its manpower could be stretched. When a design is presented, the first question AERB asks is whether it has been built and operated anywhere in the world. If not, every detail must be verified before proceeding. Regulators everywhere face the same issue: even if a design exists on paper, full assurance for such complex technology comes only after a plant has been built and operated for some time.

The AERB has already evaluated Russian reactor designs in detail, as well as French and American designs at the preliminary stage. It has confidence in proven reactor designs operating abroad. For such reactors, India-specific compliances must be verified, but the Board will not readily approve untested or purely theoretical designs. In my opinion, so far, AERB has never faltered.

India’s capability is equal to that of any country in the world, so I personally would not want my designs to be peer-reviewed by a foreign agency. If a private entity wishes to do so, it can, but otherwise our regulatory reviews are often more thorough than those in many countries that have not built reactors themselves.

I would not claim expertise in all these areas, but I believe a clear decision is needed instead of prolonged discussions and debates. Every option has pros and cons, but we must choose the path that best serves national interest. Without decisive action, years will be lost to doubt and indecision.

It would also be a mistake if every utility decided to develop a different reactor design. The supply chain would suffer. The country should agree on a common approach, as India has only five to ten factories capable of manufacturing critical reactor components. These are complex issues that require time and careful thought.

So far, we have added only 8GW of nuclear capacity. China, in comparison, has over 30GW. Progress comes from action, not discussion. China’s example proves this—after liberalisation in the 1990s, it collaborated with the US, France, Canada and Russia, evaluated all reactor technologies, identified the best approach and has since expanded rapidly. While we count in single digits, China’s reactors grow in tens.

Replacing a thermal plant with multiple 220MW SMRs is not a practical route to reaching the 100GW target. NPCIL already has a proven 700MW design—Kakrapar-1 and 2 are operational, Rajasthan-7 was connected to the grid this year and Rajasthan-8 may become operational in 2026. Building three 220MW BSRs will take longer than constructing one 700MW reactor, since the effort per reactor is similar.

SMRs are relatively costlier due to the principle of economy of scale. They are more suited for niche applications such as supplying clean power to steel plants or refineries facing green taxonomy requirements. However, they have an advantage: a smaller fuel quantity means less radioactive inventory within the reactor. In the event of a severe accident, the radiological burden would be lower. From a site-selection perspective, this could be an advantage.

Unless we act sincerely and address public fears about radiation and health risks, nuclear energy may struggle to meet expectations. To me, as to many professionals in reactor engineering, it is clear that without nuclear power India cannot achieve net zero while meeting the industrial energy demands essential for development.

Solar energy works well for rooftops where electricity can be self-consumed, but running large factories round the clock solely on solar is not feasible. Large-scale storage for several days is also impractical. For sustained industrialisation and improved living standards, the contribution from nuclear energy must increase.

Initial steps have been taken; the follow-up actions must now be completed if we are to succeed.