India's pursuit of a massive nuclear energy expansion to meet its clean power goals faces critical questions around technology choice, safety, and financing. In an exclusive interview, the country's top nuclear scientist, Dr Anil Kakodkar, provided a roadmap, highlighting both the promise and the pitfalls of emerging technologies like Small Modular Reactors (SMRs) while championing home-grown Pressurised Heavy Water Reactors (PHWRs) as the key to unlocking the thorium-based future.
The SMR Conundrum: Viability and Safety Concerns
While globally touted as a solution for decentralised power needs, such as for data centres or industrial clusters, the viability of Small Modular Reactors (SMRs) in India is not yet assured. Dr Anil Kakodkar, former Chairman of the Atomic Energy Commission, emphasised that SMRs will remain questionable until their order books expand significantly and local value addition nears 100%.
He raised a crucial safety consideration: smaller reactors would mean deploying a larger number of individual units. This inherently increases the statistical risk of a major accident unless each unit's safety standards are proportionately higher. "Not all SMRs would meet this criteria," Kakodkar cautioned, advising that any deployment must keep these aspects in mind.
PHWRs: The Workhorse for India's Thorium Ambition
Shifting focus to India's indigenous strength, Kakodkar strongly advocated for scaling up the PHWR programme. He stated that the home-grown PHWR technology is fully mature and offers competitive advantages in economics, safety, and uranium utilisation.
More importantly, he outlined a strategic shift that could accelerate India's three-stage nuclear programme. With India now able to build large PHWR capacity using imported uranium fuel, it can use these reactors to convert thorium into fissile uranium-233 by irradiating thorium alongside HALEU (High Assay, Low Enriched Uranium).
This approach enables the launch of the thorium-based power generation phase earlier, without having to wait for the large-scale deployment of Fast Breeder Reactors (the second stage). The used fuel from these PHWRs can later be recycled to set up additional capacity, including through advanced reactors like Molten Salt Reactors (MSRs). "This will enable faster energy independence from imported nuclear fuel," Kakodkar affirmed.
New Legislation and the Private Sector Role
Commenting on the recently passed SHANTI Act 2025, Kakodkar welcomed the alignment of the 'right of recourse' provisions with global practice. He noted that the previous liability clause, influenced by the Union Carbide incident, had blocked new supplier entry by leaving large residual liability on their books.
Under the new framework, the aspect of responsibility for damages from latent defects would be a matter settled between the operator and the supplier, with the operator holding ultimate responsibility. On the enhanced role for the private sector envisioned by the Act, Kakodkar reiterated that nuclear power is competitive without subsidies but should enjoy a level playing field with renewables.
He sees a clear niche for private participation in building small nuclear plants for industrial captive use and for leveraging brownfield sites of retiring coal plants. However, for the main grid-scale baseload supply, scaling PHWR capacity to a target of 50-80 GW by 2047 will require bringing in multiple players, with NPCIL providing constructive mentoring.
Kakodkar concluded that while well-proven Light Water Reactor (LWR) technology from abroad could provide useful additionality, the real answer to geopolitical vulnerabilities in fuel or technology supply lies in achieving energy independence through the thorium route at the earliest.
