Dr. Arvind Kumar*
The UNEP’s warning of a converging “polycrisis” underscores a central reality: environmental degradation, climate change, and geopolitical instability are all being intensified by a fossil-fuel-dominated energy system that still powers the bulk of the global economy. Despite rapid growth in renewables, fossil fuels continue to anchor energy supply, locking in emissions while simultaneously exposing countries to acute security risks as starkly demonstrated by disruptions linked to the Russia–Ukraine War and tensions around the Strait of Hormuz. Climate science, makes clear that this trajectory is incompatible with a stable climate, yet the transition remains structurally incomplete due to the variability and system constraints of solar and wind. In this context, civil nuclear energy is re-emerging globally as a pragmatic complement: a firm, low-carbon source capable of enhancing both energy security and decarbonisation. India’s advancing three-stage programme, particularly the fast breeder pathway, reflects this strategic shift toward long-term energy independence. Notably, just days ago, Narendra Modi described the achievement of criticality at the Prototype Fast Breeder Reactor as a “defining step in India’s civil nuclear journey”, highlighting it as a milestone that strengthens technological capability and energy self-reliance.
The planetary crisis remains deeply rooted in a fossil-fuel-dominated system, with coal, oil, and gas accounting for about 86.5% of global primary energy use in 2025 and roughly 61% of electricity generation—despite record growth in clean energy. This dependence not only locks in nearly 81% of energy-related greenhouse gas emissions but also embeds systemic risk into the global economy. As the Russia–Ukraine War or today’s intensifying US–Israel–Iran war around the Strait of Hormuz have shown, energy systems reliant on fossil supply chains are acutely vulnerable to geopolitical shocks. Disruptions to tanker traffic, surging war-risk premiums, and shutdowns of critical Gulf energy infrastructure have driven price volatility, revealing that what is often termed “energy security” is, in reality, a fragile dependence on uninterrupted and conflict-exposed fossil fuel logistics.
At the same time, climate science leaves little room for ambiguity. The IPCC AR6 Synthesis Report makes clear that fossil fuel combustion continues to be the principal driver of greenhouse gas emissions, and that existing and planned fossil infrastructure alone risks overshooting the remaining 1.5°C carbon budget by hundreds of gigatonnes of CO₂. Pathways consistent with 1.5°C require a near-total phaseout of unabated coal (≈95% by 2050), alongside steep reductions in oil (≈60%) and gas (≈45%), even with carbon capture in play.
The global response is underway but structurally incomplete. Renewables reached roughly 31% of global electricity generation in 2025, with clean sources approaching two-fifths of total power. More critically, dominant renewable sources such as solar and wind are inherently variable, introducing challenges of intermittency, grid integration, transmission capacity, and storage. As highlighted by the IEA Renewables Report, deployment at scale is constrained by permitting delays, financing gaps, and infrastructure bottlenecks.
That is where civil nuclear energy deserves a fresh, hard‑headed look. According to the IAEA, nuclear plants supplied almost 10% of the world’s electricity in 2025 and about a quarter of all low‑carbon electricity, from 413 reactors with around 371.5 GWe of capacity operating at a median capacity factor of about 88%. Life‑cycle assessments consistently show nuclear’s greenhouse‑gas footprint to be among the lowest of any generating option: median estimates of around 5–12 gCO₂‑equivalent per kWh are roughly 30 times lower than coal and 7–15 times lower than gas, and broadly comparable to wind and better than the average for solar. Global politics is starting to acknowledge this. At COP28 in Dubai, more than 20 countries launched a declaration to work towards tripling global nuclear capacity by 2050, explicitly recognising its “key role” in achieving net‑zero,this emerging nuclear consensus is not ideological; it is pragmatic.
India’s nuclear moment
India has long understood the strategic logic of nuclear energy. In the 1950s, Homi Bhabha conceived the three‑stage nuclear power programme to convert India’s modest uranium reserves and vast thorium deposits into long‑term energy independence: stage one based on natural‑uranium PHWRs, stage two on plutonium‑fuelled fast breeder reactors, and stage three on thorium‑based advanced reactors. Despite this vision, nuclear today provides only about 2–3% of India’s electricity around 48–56 TWh in recent years far below its potential in a country whose power mix remains dominated by coal.
That may be about to change. As of 2024–25, India operates roughly 24–25 nuclear reactors with an installed capacity close to 8.8 GWe, and has plans and projects lined up to lift this to about 22–23 GWe by around 2031–32 through 18 new reactors totalling some 13.6 GWe. The real strategic inflection point, however, is the Prototype Fast Breeder Reactor (PFBR) at Kalpakkam. Recently the 500 MWe PFBR attained first criticality, marking India’s historic entry into the second stage of Bhabha’s programme and placing it among the very few nations operating commercial‑scale fast breeders allowing it to generate more fissile material than it consumes, and is designed to later accommodate thorium‑232 to breed uranium‑233 for the third stage. By closing the fuel cycle, recovering and recycling fissile and fertile materials from spent fuel rather than discarding them the breeder route drastically improves uranium utilisation, reduces high‑level waste volumes, and builds the bridge to a future thorium‑based fleet anchored in India’s own mineral endowment.
In March 2026, the Union Cabinet approving a new NDC for 2031–35 that targets a 47% reduction in emissions intensity by 2035 and at least 60% of installed power capacity from non‑fossil sources by 2035 building towards net‑zero by 2070. Fast breeder technology gives India a uniquely strategic lever to change that. Once the PFBR reaches rated power and a series of follow‑on breeders are sanctioned, the second stage can multiply fissile material, enabling a larger fleet of reactors without corresponding increases in imported uranium If India’s nuclear expansion to roughly 22–23 GWe by the early 2030s stays on track, nuclear could rise from around 3% to perhaps 8–9% of electricity generation by the 2040s, significantly easing the decarbonisation of a coal‑heavy grid.
None of this is automatic, and nuclear’s critics point to real challenges that Indian policymakers must confront honestly. The PFBR itself is a case in point: construction began in 2004 and an estimated cost of about ₹3,482 crore, but first criticality came roughly 15 years late with costs ballooning to over ₹8,000 crore, more than double the initial estimate largely due to the complexity of first‑of‑a‑kind sodium‑cooled technology, specialised materials and project‑management hurdles. More broadly, nuclear plants have very high upfront capital costs, long construction timelines, and safety and waste management are equally critical to social licence. Sodium‑cooled fast reactors demand meticulous control of a coolant that reacts violently with air and water, raising legitimate concerns about operational risk and accident management capacity. India still lacks a fully implemented, robust long‑term geological disposal framework, even as spent fuel volumes grow, and the Atomic Energy Regulatory Board’s limited statutory independence has invited criticism and calls for a more autonomous nuclear regulator.
Way Forward
If India is to make civil nuclear energy especially its fast breeder and thorium pathway a credible pillar of energy security and climate action, it needs treating safety, transparency and participation as non‑negotiable, by strengthening the nuclear regulatory framework into a genuinely independent statutory commission, opening up more data on reactor performance and incidents, and engaging local communities early and meaningfully on land, livelihoods and emergency preparedness. It also means integrating nuclear expansion into a holistic power‑sector plan where reactors are sited and sized to complement renewables, grid upgrades and storage, rather than competing with them in policy silos. On the economic side, India will have to innovate in financing through long‑tenure green bonds, sovereign guarantees and perhaps carefully designed public–private partnerships for components and fuel supply while standardising reactor designs and exploring future small modular reactors to cut costs and build times. At the international level, New Delhi should leverage the growing global consensus on nuclear’s climate role reflected in the COP28 tripling declaration to secure technology collaboration, fuel‑supply diversification and climate finance for its three‑stage programme. Done right, civil nuclear energy will not replace renewables or efficiency; it will anchor them providing firm, low‑carbon power in a world buffeted by climate shocks and energy wars, and giving India a realistic shot at simultaneous energy security, development and climate justice.
*Editor, Focus Global Reporter
