The Office of Atoms for Peace (OAP), as the national regulatory body for nuclear and radiation safety in Thailand, has closely followed and drawn valuable lessons from the historic milestone of Bangladesh. On October 11, 2026, at 4:34 PM (Thailand time), the reactor Unit 1 of the Rooppur Nuclear Power Plant successfully initiated its first controlled nuclear chain reaction, achieving “First Criticality.”
This represents a significant step forward in strengthening the region’s energy security.
Understanding Rooppur and the Journey to First Criticality Located in the Pabna district, the Rooppur Nuclear Power Plant utilizes the Russian-designed VVER-1200 pressurized water reactor technology.
The plant consists of two units with a combined generation capacity of 2,400 megawatts.
From an engineering and regulatory perspective, “First Criticality” is a vital stage in initiating a reactor’s operation. It marks the point where the nuclear chain reaction becomes self-sustaining under strictly controlled conditions, allowing the generated heat to produce steam that drives the turbines to generate electricity.
Safety First: From Reactor Operation to Grid Connection
OAP emphasizes that achieving First Criticality does not mean electricity can be immediately supplied to the grid. What Bangladesh is currently undertaking is a phase of “rigorous testing and evaluation.” Engineers and the Bangladeshi regulatory body must collaboratively verify the safety systems and equipment functionality while gradually increasing the power output in stages.
These processes reflect the stringent regulatory standards required before the actual connection to the power grid, which is targeted for late November 2026.
Crucial Lessons for Thailand’s Preparation
The success of the Rooppur project serves as a highly valuable case study for Thailand, particularly as we are preparing and studying the feasibility of Small Modular Reactor (SMR) technology. OAP has identified key success factors that Thailand can adapt:
• Robust Regulatory Framework: The construction and operation of a nuclear power plant must be subjected to strict safety oversight at every stage.
• Specialized Human Resource Development: Operating advanced technology requires specialized engineers and personnel. This aligns with the policies of OAP and the Ministry of Higher Education, Science, Research and Innovation (MHESI), which are actively accelerating workforce development.
• International Cooperation: Collaborating with experts from the technology provider country and international organizations like the IAEA is a vital mechanism for building standards and public trust.
• Infrastructure Readiness: Both the electrical grid system and environmental impact assessments must be fully prepared to support the new technology.
The Office of Atoms for Peace (OAP) will continue to advance its preparations in terms of legislation, safety standards (Safety, Security, Safeguards), and human resources. This is to ensure that if Thailand decides to pursue alternative nuclear energy such as SMRs in the future, we will have a robust ecosystem and regulatory mechanism ready to protect the public and the environment to the highest international standards.
Written by:
Dr. Rungrueng Kitphati, Secretary General, Office of Atoms for Peace, Ministry of Higher Education, Science, Research and Innovation.
Acknowledgment: Information provided by Nuclear Engineering, Chulalongkorn University.
References:
• New Age Bangladesh: Rooppur’s first controlled nuclear reaction begins, power generation due by late November.
• The Daily Star: Rooppur unit-1 begins first nuclear fission reaction.
• International Atomic Energy Agency (IAEA): Bangladesh National Report to the Convention on Nuclear Safety.
• Image credit: Rosatom
