Atomic Energy Regulatory Board Approves Restart of Tarapur Atomic Power Station Unit-2

Key Facts

• Date of AERB clearance: 7 May 2026
• Plant location: Near Boisar, Palghar district, Maharashtra
• Unit-2 operation extended by 10 years following major refurbishment
• Reactor type: Boiling Water Reactor (BWR)
• Power capacity: Rated at 160 MWe
• Refurbishment executed by: Nuclear Power Corporation of India Limited (NPCIL)
• Unit-1 restarted earlier, in December 2025, now operational at full capacity
• Safety upgrades include complete replacement of reactor coolant recirculation piping with corrosion-resistant stainless steel forged piping and fittings, commissioning of a Reactor Containment Filtered Venting System, and an Alternate Cooling Water System
• AERB conducted multi-tiered safety reviews before approval
• AERB continues regulatory oversight and will monitor safety performance of both Units 1 and 2

Background & Context

Tarapur Atomic Power Station, located near Boisar in Palghar district of Maharashtra, was India’s first nuclear power station, with Units 1 and 2 commissioned in 1969. Both units are Boiling Water Reactors (BWRs), which use water as both coolant and moderator in the reactor core. These units were Asia’s first commercial nuclear power reactors. Over decades of operation, aging components necessitated extensive refurbishment and safety upgrades to ensure continued safe operation. The refurbishment aimed to replace aging reactor components prone to corrosion, enhance safety systems to contemporary standards, and conduct comprehensive inspections, including ageing and residual life assessments of critical reactor components such as reactor pressure vessel welds. The refurbishment enables extension of operational life by 10 years, applying lessons learned and aligning with India’s nuclear safety regulations overseen by the AERB.

Why This Matters for Exams / Exam Relevance

The restart of Tarapur Unit-2 is a significant event in India’s nuclear energy sector, demonstrating government regulatory processes, safety oversight, and infrastructure modernization initiatives. Competitive exams may test knowledge of India's nuclear energy infrastructure, key regulatory bodies like the AERB, roles of NPCIL, and reactor technology (BWRs). Furthermore, the refurbishment of the country’s first nuclear power units encapsulates themes of technological lifecycle management, nuclear safety, and energy security – topics pertinent to general studies in environment, science, and current affairs syllabi.

Points to Remember

• The Atomic Energy Regulatory Board (AERB) is India's nuclear safety regulator, responsible for authorizing reactor operations.
• Tarapur Atomic Power Station consists of two original BWR units (Units 1 & 2), commissioned in 1969, and two later Pressurized Heavy Water Reactors (Units 3 & 4).
• Units 1 and 2 underwent major refurbishment to replace reactor coolant recirculation piping with advanced corrosion-resistant forged stainless steel piping, enhancing operational safety and longevity.
• Additional safety systems added include Reactor Containment Filtered Venting System and Alternate Cooling Water System, crucial for mitigating severe accident scenarios.
• Unit-1 was safely restarted in December 2025 and is currently operating at its rated power of 160 MWe.
• Unit-2 restart approved on 7 May 2026, allowing extended operation for 10 more years.
• Rigorous technical assessments, inspections, and multi-tier safety reviews by AERB underpinned restart approval.
• Boiling Water Reactors (BWRs) use light water as coolant and neutron moderator, a common reactor type with focus on safety and efficiency.
• MWe denotes megawatt electric, the measure of electrical power output from the reactor.