Bangladesh's first reactor, Rooppur 1, reaches criticality
Victoria Shinder2 min readThe first unit of the Rooppur Nuclear Power Plant in Bangladesh achieved criticality — a self-sustaining chain reaction — at 15:34 on Sunday, 11 October 2026, World Nuclear News reported. It is the country's first nuclear reactor to reach this stage, and it came three days after the national regulator gave the go-ahead.
What happens next. The project's statement describes the sequence: after criticality, testing and safety verification continue and the reactor is operated at the minimum controllable power level; only if those tests succeed will supply to the national grid be advanced step by step. Rosatom Director General Alexey Likhachev, who held talks in Moscow with Bangladesh's science and technology minister Fakir Mahbub Anam two days earlier, said that once this phase is complete the unit will be ready for the power start-up phase and then grid connection. According to Rosatom's in-house publication Strana Rosatom, power start-up is scheduled for 20 November, with further tests and checks before and during the staged increase in output.
A project fifteen years in the making. Rosatom signed the agreement to build two reactors at Rooppur, about 160 km from Dhaka, for the Bangladesh Atomic Energy Commission in February 2011; the initial contract, worth $12.65bn, followed in December 2015. The Bangladesh Atomic Regulatory Authority issued the site licence in June 2016, construction of unit 1 began in November 2017 and of unit 2 in July 2018. Both are designed for a 60-year life with a possible 20-year extension.
The last two years. The first fuel arrived in October 2023, making the site a nuclear facility. Turbine installation, primary-circuit hydraulic tests and hot functional tests followed. The Bangladesh Nuclear Regulatory Authority issued the operating licence on 16 April 2026, and loading of 163 fuel assemblies into the reactor was completed in May.
For Bangladesh the milestone matters less as a megawatt figure than as a change of category: a country without nuclear generation now has a reactor in its start-up programme, with grid connection depending on the tests of the coming weeks.
Source: World Nuclear News, "Bangladesh's Rooppur 1 achieves criticality" — https://www.world-nuclear-news.org/articles/bangladeshs-rooppur-1-achieves-criticality