How do Small Modular Reactors differ from conventional nuclear plants, and what advantages do they offer for India's decarbonisation goals?

Q. How do Small Modular Reactors differ from conventional nuclear plants, and what advantages do they offer for India's decarbonisation goals? (15 marks, 250-350 words)

Small Modular Reactors (SMRs) are advanced fission reactors of a few hundred MWe or less, built as factory-fabricated modules and assembled on site. Under the Nuclear Energy Mission (Union Budget 2025-26), India has earmarked ₹20,000 crore to make at least five indigenous SMRs operational by 2033 [1] — making them pivotal, not peripheral, to decarbonisation.

How SMRs differ from conventional plants - Scale: BARC's designs — BSMR-200 (220 MWe) and SMR-55 (55 MWe) — are a fraction of conventional 700–1000 MWe units [1]. - Construction model: standardised modules are shop-fabricated and transported, versus bespoke on-site megaprojects; BSMR construction is estimated at 60–72 months from financial sanction [1]. - Siting flexibility: smaller footprint and passive safety allow deployment at compact or brownfield sites — lead units are planned at Tarapur, and the HTGCR at Vizag [1]. - Purpose: the High Temperature Gas Cooled Reactor (up to 5 MWth) targets hydrogen production, not electricity — a role conventional plants cannot fill [1]. - Ownership: the SHANTI Act, 2025, replacing the Atomic Energy Act, 1962 and the Civil Liability for Nuclear Damage Act, 2010, opens the civil nuclear chain to regulated private entities [2].

Advantages for India's decarbonisation - Firm clean baseload that complements variable solar and wind, easing the grid-balancing burden of the renewables push. - Hard-to-abate sectors: captive SMRs can decarbonise steel, cement and aluminium, where electrification alone is insufficient; HTGCR-derived hydrogen supports the green hydrogen agenda [1]. - Lower capital lumpiness and faster build, improving bankability once private capital enters under SHANTI [2]. - Anchors the 100 GWe-by-2047 target, itself the bridge to net-zero by 2070 [1].

SMRs thus convert nuclear power from a few large, slow assets into a scalable, industry-facing clean-energy option. Realising this promise requires timely Cabinet sanction, regulatory capacity in the strengthened AERB, and supply-chain readiness. Sustained on this path, SMRs can make Viksit Bharat's growth compatible with its climate commitments.

(~325 words)

Sources: 1. PARLIAMENT QUESTION: DEPLOYMENT OF SMALL MODULAR REACTORS (SMRs) — PIB, Department of Atomic Energy — Nuclear Energy Mission, ₹20,000 crore outlay, five SMRs by 2033, BSMR-200/SMR-55/HTGCR designs and capacities, Tarapur and Vizag sites, 60–72 month construction, 100 GWe by 2047 and net-zero 2070 linkage 2. The Sustainable Harnessing and Advancement of Nuclear Energy for Transforming India (SHANTI) Bill, 2025 — PIB — replacement of the Atomic Energy Act, 1962 and Civil Liability for Nuclear Damage Act, 2010; regulated private participation in the civil nuclear sector