SMRs in Thailand by 2037: Building the Backbone of Industrial Expansion
Thailand’s third attempt at nuclear power is emerging at a moment when capital, technology, and industrial demand are aligning in ways that were absent in previous cycles, but whether this translates into a bankable opportunity remains an open question. As ASEAN economies compete to attract energy-intensive industries such as data centres, AI infrastructure, and advanced manufacturing, the availability of reliable, low-carbon baseload power is becoming a decisive investment filter. Thailand’s proposed SMR programme sits at the intersection of this shift, supported by a more credible international partnership framework and a technology pathway better suited to its grid and institutional capacity. Yet for investors and vendors, the critical issue is not intent but execution: whether this iteration meaningfully resolves the structural mismatches that caused earlier failures, or simply repackages them in a more investable form at first glance.
What Failed the First Two Times
The first attempt collapsed because an economic alternative appeared. When domestic fossil fuel reserves were discovered in the Gulf of Thailand, the rationale for the higher capital cost and complexity of nuclear power simply dissolved. The second attempt collapsed because of public fear triggered by an external event, the Fukushima accident, combined with the specific technology being proposed: a 2,000 MW conventional large reactor. At that scale, the safety concerns, land requirements, and visibility of the project made it an easy target for public opposition. Thailand's government at the time had no credible technical counter-argument to offer.
Both failures share a common feature. The technology being proposed did not match Thailand's specific conditions. A large conventional reactor requires a high-capacity grid capable of absorbing its full output without stability risk, a deep domestic talent pool for operation and maintenance, and public confidence in a technology that was new and unfamiliar. Thailand had none of these in sufficient measure. The question in 2026 is whether the third attempt has addressed these gaps, or whether it is repeating the same mismatch in a different form.
The Technology Choice Is the Critical Difference
The PDP 2024 targets two 300 MW Small Modular Reactors, totalling 600 MW, with construction beginning in 2032 and commercial operations expected by 2037. The reactors will be developed and operated by the Electricity Generating Authority of Thailand (EGAT), and the capacity will be split geographically: 300 MW in the Northeast and 300 MW in the South. This geographic distribution is not incidental. It reflects a deliberate decision to integrate nuclear into Thailand's grid at nodes where the existing transmission infrastructure can absorb it without requiring the large-scale grid upgrades that a single large plant would demand.
The choice of SMRs rather than conventional large reactors directly addresses the two failure modes of the previous attempts. On the public acceptance side, SMRs are designed with passive safety systems that allow the reactor to cool without operator intervention or external power, which was the precise failure mechanism at Fukushima. They incorporate underground containment, reducing the potential for radiation release into the environment. Their smaller reactor cores contain less fissile material and thermal energy than large plants, giving them a lower overall risk profile that is easier to communicate and defend publicly. Land-based water-cooled SMRs are particularly well suited to Thailand given the country's abundant water resources, which support the cooling requirements these designs depend on.
On the grid integration side, 300 MW units are compatible with medium-sized transmission grids in a way that a 2,000 MW plant simply is not. Thailand does not need to rebuild its transmission infrastructure to accommodate SMR deployment. It needs to site the units sensibly, which the Northeast and South regional split already reflects. These are not trivial differences from the 2010 programme. They represent a fundamentally different approach to the same problem, and one that is technically better matched to Thailand's conditions.
The Partnership Architecture Is New and Substantive
On March 21, 2025, the Thai government signed an agreement with South Korea covering nuclear research and development, knowledge sharing, technology exchange, and expert collaboration. This was followed on June 10, 2025 by a formal MoU between Korea Hydro and Nuclear Power (KHNP) and EGAT, focused specifically on SMR technology feasibility, best practice exchange, and human resource development through training, site visits, and joint programmes. KHNP brings the most directly relevant reference credentials available: the APR-1400 units at Barakah are the most recently completed large nuclear construction project in the world, delivered on schedule to a newcomer nation. Its engagement with EGAT on SMR feasibility is the most commercially significant bilateral agreement in Thailand's current nuclear programme.
The United States 123 Agreement, which came into effect on July 9, 2025, provides a separate and important foundation. It enables the transfer of nuclear materials, equipment including reactors, components, and information for civilian nuclear energy and research, while embedding non-proliferation commitments that give the programme international legitimacy. For Western vendors including Westinghouse and GE Hitachi, the 123 Agreement is the legal prerequisite for commercial engagement in Thailand. Its entry into force in 2025 opens the Thai market to the full range of American nuclear technology suppliers for the first time.
Alongside these government-level agreements, Thai company Global Power Synergy signed an MoU with Denmark's Seaborg Technologies in April 2024 to explore the deployment of a Compact Molten Salt Reactor on a power barge in Thailand. This is an early-stage technology exploration rather than a committed procurement, but it signals that Thai private sector energy companies are independently evaluating advanced nuclear options beyond the government programme.
The Demand Context That Was Not Present Before
The first two attempts at nuclear in Thailand were driven primarily by energy security concerns. The demand context in 2026 is different in a way that strengthens the investment case considerably. Thailand is competing within ASEAN for industrial investment, particularly in sectors that require large quantities of clean, reliable power. AI infrastructure, data centres, and advanced manufacturing are expanding rapidly across Southeast Asia, and the countries that can offer low-carbon baseload power will attract a disproportionate share of that investment. Thailand's competitors in this race, including Vietnam, Malaysia, and Indonesia, are all advancing nuclear programmes with varying levels of urgency.
The SMR programme is an infrastructure commitment that will shape Thailand's industrial competitiveness well into the second half of this century. For international investors and vendors evaluating the Thai market, the combination of a technology choice better matched to local conditions, a substantive international partnership structure, and an industrial demand context that rewards clean baseload power makes this attempt at nuclear energy qualitatively different from the two that preceded it. Whether Thailand executes on that potential depends on decisions that will be made in the next three to four years.
The procurement window for SMR vendor selection will be one of the defining commercial events in Southeast Asian nuclear development this decade, shaped not only by national policy choices, but also by industry platforms such as the Asia Nuclear Business Platform (ANBP) 2026, where policymakers, investors, and vendors are refining financing and partnership models while building the relationships that ultimately determine market access.
