Unit 1 of the Rooppur Nuclear Power Plant in Pabna has officially initiated its controlled nuclear fission reaction, marking a critical milestone in the final process of power generation and distribution.
This achievement brings the country’s sole nuclear power installation significantly closer to commercial operation, with initial plans to feed 300 megawatts (MW) of electricity into the national grid in December.
In financial terms, the nuclear installation represents the largest single project in Bangladesh’s history.
Safety tests and regulatory approval
Unit 1 nuclear reactor vessel achieved criticality for the first time on Sunday at 3:34pm, following three days of preparatory procedures that commenced on Saturday.
The fission reaction was originally slated for September, but was delayed after defects were identified during safety valve testing.
High-pressure safety valve tests were subsequently completed in two phases last week, leading the Bangladesh Atomic Energy Regulatory Authority (BAERA) to grant formal approval for the reaction on Thursday.
Md Zahedul Hasan, managing director of Nuclear Power Plant Company Bangladesh Limited (NPCBL), stated that the controlled reaction commenced successfully on Sunday, bringing an end to a long journey in nuclear energy utilisation that originally began in 1961.
He described the milestone as a significant breakthrough for the national science sector.
Plant officials emphasised that achieving reactor criticality represents far more than a technical victory, standing as an historic recognition of Bangladesh’s scientific, engineering, and nuclear technology capabilities.
Testing roadmap and grid integration
All vital parameters of the reactor vessel currently remain strictly within approved safety limits under controlled conditions.
Following the approved commissioning programme, officials confirmed that the plant will now undergo reactor physics tests, safety system verifications, incremental power escalation, and grid connection preparations.
This comprehensive testing phase will take between 30 and 40 days to complete, during which atomic fission generates thermal energy to create steam that turns the turbines to produce electricity.
Once reactor thermal output reaches 30 per cent of capacity, initial power transmission of 300 MW to the national grid will begin, targeted for December.
Experimental power production is expected to continue for seven to eight months following initial activation. Once electricity is supplied to the national grid, Bangladesh will officially become the world’s 33rd nuclear power-producing nation.
Bangladesh had previously joined the rank of nuclear-capable nations in October 2023 when nuclear fuel was formally received at the project site.
Operational parameters and project financials
Once fully operational, the power station will supply uninterrupted base-load electricity 24 hours a day. The reactor will require refuelling every 1.5 years, with each unit experiencing a maximum shutdown of two months for maintenance, spent fuel removal, and refuelling operations.
Operating a single unit is projected to save nearly $1 billion annually in fossil fuel import costs, despite overall project implementation lagging three and a half years behind schedule.
The mega-project is being implemented by the Bangladesh Atomic Energy Commission under the Ministry of Science and Technology, with operational management handled by state-owned NPCBL.
Russian contractor Atomstroyexport is constructing two 1,200 MW units at the site, bringing total plant capacity to 2,400 MW. Although the original project completion deadline was December 2025, it has been extended twice to June 2028.
Under the terms of the agreement with the contractor, project costs cannot be increased due to timeline extensions; however, currency fluctuations involving the US dollar have raised costs by Tk26,000 crore, taking total expenditure to Tk1,38,686 crore.
