Thailand Charts Regulatory Path for Small Modular Reactors in Draft 2026 Energy Plan

Thailand is preparing to bring nuclear power back into its energy mix, but this time through a different door. The country's draft Power Development Plan for 2026 proposes deploying small modular reactors—units roughly one-third the size of conventional nuclear plants—starting with an initial 300 megawatt facility between 2026 and 2037, followed by a much larger buildout to around 9,000 megawatts by 2050. The Electricity Generating Authority of Thailand, the state utility, is expected to develop the first unit, and the plan awaits approval from the National Energy Policy Council. In September 2026, EGAT and the US Trade and Development Agency signed an agreement to study the feasibility of SMRs around 600 megawatts in capacity, examining seven American designs.

This represents Thailand's third serious attempt at nuclear power. In 1966, the country planned a 600 megawatt plant in Chonburi, only to shelve it after natural gas was discovered in the Gulf of Thailand. The 2007 Power Development Plan proposed two 1,000 megawatt units, but those were postponed after the Fukushima accident in 2011 and dropped entirely from the 2018 plan. What makes this attempt different is both the technology and the legal infrastructure now in place. Small modular reactors can be factory-built and shipped in components, allowing capacity to be added module by module. They require a much smaller footprint—roughly 100 rai of land rather than 1,000 rai—and their emergency planning radius extends less than one kilometer instead of 16 kilometers. Construction timelines are shorter, typically three to four years rather than five to six.

Thailand's regulatory framework for SMRs is split between two agencies operating under a 2024 inter-agency agreement. The Office of Atoms for Peace, under the Nuclear Energy for Peace Act, handles nuclear safety, security, and safeguards. The Energy Regulatory Commission, under the Energy Industry Act, regulates energy business licensing, tariffs, and grid access. A joint sub-committee will screen licensing applications, adopt cyber security measures, and conduct joint inspections when complaints arise. At the policy level, the National Nuclear Energy Policy Committee sets national nuclear strategy, and in September 2026 it considered a regulatory framework for SMRs. The two agencies are planning to establish a one-stop service center to coordinate more than 40 agencies and 40 permits relevant to an SMR plant, aiming to reduce duplication and delay.

The most visible gap in Thailand's readiness is the absence of a Nuclear Energy Programme Implementing Organization, or NEPIO. This body would coordinate national policy, review the International Atomic Energy Agency's 19 infrastructure issues, and host the IAEA's first Integrated Nuclear Infrastructure Review mission. A preliminary self-assessment rated ten of those 19 issues as largely ready, including nuclear safety, legal frameworks, safeguards, and emergency preparedness. Six issues need further work: human resources, stakeholder involvement, site selection, environmental protection, the nuclear fuel cycle, and industrial involvement. Three require urgent action: establishing a clear national position, creating a management structure, and securing funding and financing. The timeline EGAT has outlined spans two to three years for project preparation, four to five years for implementation leading to a developer agreement, and five to six years for construction—roughly 11 to 13 years from inclusion in the plan to operational readiness.

The regulatory questions that remain are largely about how the two agencies will coordinate at their interfaces. On licensing, Thailand could adopt a joint licensing roadmap without legislative change, or it could move toward a combined construction and operating license modeled on the US approach, which would require amending the Nuclear Act. The staged model under current law calls for separate site, construction, operation, and decommissioning licenses, alongside an energy business license from the ERC. Multi-module sites raise the question of whether one license can cover several units or whether each addition requires a new permit. On tariffs, the ERC's existing revenue cap methodology could apply, but the challenge is capital intensity. Public hearing materials cited a capital cost of around 202,164 Thai baht per kilowatt for the first unit, expected to fall to 178,500 baht per kilowatt by 2050 as the technology matures. The allocation of construction and cost-overrun risk will shape project financing more than any other decision. Options range from a revenue cap model that places risk largely on consumers, to a Regulated Asset Base model that shares risk and allows returns during construction, to a Contract for Difference that places more risk on the developer.

Grid integration presents its own set of technical and operational questions. EGAT is pursuing 500 kilovolt transmission reinforcement projects intended to form a national backbone across multiple regions, and SMR site selection will need to align with this infrastructure. The dispatch status of SMRs within Thailand's merit order system remains unsettled; given their high fixed costs and low variable costs, they may not fit comfortably within the existing framework. Possible approaches include must-run status on system security grounds, must-take status under a power purchase agreement, or a dedicated nuclear category that could offer the greatest certainty to investors.

Nuclear liability and decommissioning represent areas where Thailand's draft legislation is most advanced. A draft Civil Liability for Nuclear Damage Act would channel liability exclusively to the operator on a strict liability basis, cap it at 300 million Special Drawing Rights per incident—roughly 15 billion baht at current rates—and require insurance or financial security for the same amount. The bill would establish a nuclear damage compensation fund of around 400 million baht, financed by government contribution and annual operator payments. Victims would be able to claim directly without first proving entitlement, with limitation periods of 30 years for death and personal injury and 10 years for other damage. For decommissioning and spent fuel management, Thailand will need to establish segregated funds built up over the plant's operating life, with clear rules on how the ERC allows contributions to be passed through to tariffs.

For technology vendors, the path forward requires early engagement with the Office of Atoms for Peace on design review, well before formal application. EGAT's technology screening is expected to favor land-based water-cooled reactors with operating experience and regulatory familiarity, designs already in licensing elsewhere, and unit sizes of roughly 50 to 350 megawatts per module. With more than 44 SMR designs tracked globally by the IAEA, vendors of Generation IV or marine-based designs may face a higher bar in Thailand's first project. For lenders and insurers, bankability will depend on licensing certainty, clear cost-overrun allocation, and a settled nuclear liability framework. For foreign investors, while foreign ownership is not restricted, land ownership limits, director residency requirements, and the absence of Board of Investment promotion all require careful structuring. Long-term contracts spanning up to 60 years will need robust dispute resolution clauses, including international arbitration.

Public acceptance remains the decisive constraint. Past nuclear communication in Thailand has shown clear weaknesses: top-down and overly technical messaging, slow responses to misinformation, limited public participation, and low trust in government. A strategy built on transparency and early local engagement is now being emphasized. Thailand has most of the legal and institutional foundations for regulating SMRs in place. What remains is resolving the detail at the interfaces—licensing sequence, risk allocation, dispatch status, decommissioning funding, and liability. The preliminary self-assessment points to the same conclusion: the issues rated most urgent are not technical but institutional. Twice before, external events halted Thailand's nuclear plans. This time, the readiness of the legal framework and the strength of public trust may decide whether SMRs move from the plan to the grid.