Fuel for a green Viksit Bharat

Indian Express

a day ago

India's aspiration to be 'viksit' by the centenary year of its independence, while adhering to the net zero carbon emissions target for 2070, needs a strategy for sustained per capita energy use. The strategy also needs to focus on achieving a Human Development Index of 0.95, which is characteristic of advanced countries, and provide clean energy for this purpose. This corresponds to around 28,000 TWh of total energy annually. The available clean energy sources to address this need are renewable energy, large hydro power and nuclear. Among them, nuclear energy's contribution would need to be at least around 20,000 TWh annually since the other two together are unlikely to exceed 8,000 TWh. Today, India consumes around 9,800 TWh annually with around 96 per cent coming from fossil resources. Clean energy needs to increase 70 times and around 70 per cent of it needs to come from nuclear in 45 years.
After Independence, Homi Bhabha had advocated a three-stage nuclear power programme aimed at long term energy security and autonomy for the country. We seem to be losing that focus. Surely, there are constraints and challenges, some of which are external. However, a sharper focus on our end goal, despite the strong foreign vendor-driven narratives that seem to be gaining currency of late, is something we cannot afford to lose sight of.
Any nuclear programme has to necessarily begin with uranium — the only natural source of fissionable material. While our uranium resources were modest to begin with, the emphasis on exploration has led to an increase in stocks. The ore grades, however, are very low. These reserves, despite the higher cost they entail, are a key source of energy security, especially in a situation when uranium imports are disrupted. Access to foreign uranium markets has enabled the first-stage nuclear programme to grow well beyond 10 GWe, a threshold that was envisaged earlier. However, the second-stage programme of fast breeder reactors is yet to take off.
We must, however, celebrate our domestic pressurised heavy water reactors (PHWRs), the proven and competitive technology that meets global benchmarks. While the 100 GWe nuclear mission launched by the government would still leave us about twentyfold below the nuclear capacity required for a net zero 'Viksit Bharat', realising it within the specified timeframe requires accelerated deployment. This, in turn, depends essentially on proven technologies — domestic PHWRs being the primary workhorse, supplemented by proven large light water reactors (LWRs). We must also bring in multiple deployment agencies, beyond NPCIL and now NTPC. The PHWR technology must be seen as a common national good and made available to potential domestic agencies for accelerated deployment with a mentoring approach. Efforts to minimise the costs are necessary in the case of LWRs by following the Make in India approach.
100 GWe capacity would need around 20,000 tons of uranium annually. This could be around 15 per cent of global uranium production. Given the constraints of geopolitics as well as potential demand-supply mismatch in a growing nuclear energy scenario, this may well become a major energy security challenge of a dimension that is more serious compared to oil and gas today. The three-stage programme, which involves recycling nuclear fuel, enables 60-70 times more energy from the same quantity of mined fuel. A quick shift from mined uranium to recycled uranium and plutonium in fast reactors has thus become an energy security imperative. In view of the delay in deploying fast breeder reactors (FBRs), irradiating thorium, of which we have the largest reserves, in our PHWRs has become crucial. That we are now leveraging much greater quantities of uranium than envisaged earlier also enables large-scale introduction of thorium in our PHWRs. This would help us in preparing to address the energy security challenge by recycling thorium-based spent fuel in molten salt reactors (MSR) and advance the third stage despite delays in the second stage. While the plan to introduce thorium in fast reactors to lead us into the third stage should continue, this would enable a faster route to thorium MSRs. One could also link high-power GeV range proton accelerators with subcritical systems based on such configurations to facilitate capacity growth.
SMRs, which are dominating the narrative today, would take at least two decades to mature before deployment at scale can begin. Not only is this inconsistent with the 2047 timeline, the uranium required will also be harder to access at that time. Instead, we would be better off devoting our R&D resources to developing thorium MSR-based SMRs as well as other technologies relevant to the second and third stage that would take us closer to our thorium goal.
High Assay Low Enriched Uranium (HALEU) and irradiation qualification of thorium fuel for high burn-up performance are prerequisites to introducing thorium in PHWRs. They also have several advantages with respect to economics, safety, waste management and proliferation resistance — the move would be attractive without any significant change in the reactor. HALEU is also fast becoming the choice for many advanced power reactor systems just as it has become so for research reactors. This is an area for international cooperation benefiting not just India but also the emerging economy countries. ANEEL fuel, which is under development, aims to achieve just that.
One should expect the 100 GWe nuclear mission to be a forerunner to the much larger nuclear energy deployment necessary for net zero Viksit Bharat and not reach a virtual dead end.
The writer, a nuclear scientist, was director of Bhabha Atomic Research Centre