Examine the role of public sector heavy engineering enterprises in building India's nuclear power supply chain. How has fleet-mode construction changed this role?

In 1976, BHEL Tiruchi rolled out India's first nuclear steam generator, built for the 235 MW Madras Atomic Power Project-II at Kalpakkam. Until then, the steam generators for the Rajasthan station had been imported from Canada [1]. Public sector heavy engineering firms have been the base of India's nuclear supply chain since then. Fleet mode has now turned them from nominated suppliers into anchor vendors that must win orders on competition and scale.

Role of public sector heavy engineering firms

• Import substitution: BHEL made both steam generators and heavy water headers in India, replacing the Canadian equipment [1].
• Capability building: BHEL set up specialised machinery and a nuclear clean room, and trained qualified welders and engineers. Indian heavy industry had not had these before [1].
• Process innovation: BHEL's "hot pull-out" method removed the need to weld the nozzle onto the header pipe. This made the headers indigenous [1].
• Integrated supply: BHEL Tiruchi made the steam generators and BHEL Bhopal made the turbo-generators. One public sector firm covered both the nuclear and the conventional side of the plant [1].
• Strategic autonomy: Canada cut cooperation after Pokhran-I (1974). Domestic supply then protected Stage I of the three-stage programme. The contrast is Kudankulam, built with Russia, which ran 86–101 months late, partly because of late Russian supplies [4].

How fleet mode changed this role

• Bulk, standard orders: In 2017 the Cabinet approved 10 × 700 MW PHWRs in fleet mode. It expected economies of scale and about ₹70,000 crore of likely orders for domestic industry [2].
• From nomination to competition: BHEL won 12 steam generators (₹1,405 crore) through competitive bidding. This was its second such order, after 32 reactor header assemblies [3].
• Predictable demand: Repeating one design lets suppliers plan output and invest in capacity. The indigenous 700 MWe units at Kakrapar 3 & 4 are now in commercial operation [6].
• Need to scale up: The targets of about 22,380 MW by 2031–32 and 100 GW by 2047 [5] call for far more factory capacity. Public sector firms now share this work with private makers.

Public sector firms built a supply chain that no foreign power could cut off, and fleet mode has made it competitive and scalable. The way forward is to keep ordering in bulk, track supplier bottlenecks, and use private entry to widen the vendor base. That would support Atmanirbhar Bharat and SDG-7 (clean energy).