On March 30, 2026, Thailand’s Board of Investment (BOI) began requiring applicants for data center investment incentives to submit a “Power Confirmation Letter” issued by the Energy Regulatory Commission (ERC). At the same time, the Direct Power Purchase Agreement (Direct PPA) scheme launched in January 2026 has opened the door to 100% renewable sourcing for data center operators. Understanding both sides — the new regulatory step and the new procurement opportunity — is essential for Japanese companies considering data center or cloud infrastructure investments in Thailand.
1. Why a Power Confirmation Letter Now — Thailand’s DC Strategy at a Glance
Thailand has been actively promoting data center investment, particularly in the Eastern Economic Corridor (EEC). According to reporting by Nation Thailand, the Thai government has set an ambition of attracting roughly 2.87 GW of data center capacity. Major hyperscalers including Amazon Web Services, Google, Microsoft, and TikTok (whose approximately THB 28 billion investment was approved by the BOI in November 2024) have already announced or begun projects in Thailand, signaling a clear intent to position the country as a Southeast Asian hub for cloud and AI infrastructure.
But there is a significant gap between ambition and infrastructure. Reporting by Nation Thailand suggests that grid capacity in the EEC is constrained, and EGAT (the state electricity authority) is investing roughly THB 31 billion in transmission upgrades to close the gap. Data centers are highly power-intensive — typically tens to hundreds of megawatts of continuous load — and “the site is ready, but the power isn’t” is a scenario that can derail an entire investment timeline.
Layered on top is Thailand’s 2050 carbon neutrality goal and a target of 51% renewables in the generation mix. Large electricity consumers such as data center operators are increasingly expected not just to secure power, but to demonstrate that the power they consume comes from renewable sources. The ERC Power Confirmation Letter requirement is essentially a mechanism to verify, at the application stage, both the megawatt availability and (over time) the renewable readiness of each project.
For broader context on how data center infrastructure underpins AI deployment in Thailand, see also our Thailand AI Regulation Framework (2026) article.
2. What the New BOI Rule Says — Inside the ERC Power Confirmation Letter
Based on information publicly available as of April 2026, the new rule can be summarized as follows:
- Function: A document from the ERC confirming that sufficient electricity supply is available for the proposed data center project.
- Timing: Submitted at the time of investment incentive application, not after BOI approval.
- Effective date: March 30, 2026.
- Retroactivity: None. Projects already filed or already approved before the effective date are understood to fall outside the scope of the new requirement.
That said, the official BOI announcement number and full text, along with the formal application procedure, document checklist, and review timeline for the ERC Power Confirmation Letter itself, have not yet been broadly published. Further details should be monitored as BOI and ERC release additional guidance. Japanese companies planning new DC projects should build buffer time into their schedules on the assumption that the BOI approval timeline will now include an additional ERC review step.
For context: in Japan, grid connection is generally negotiated bilaterally with the relevant utility, and an administrative agency does not pre-verify electricity availability as part of an investment approval. Thailand’s new regime thus introduces a more interventionist, front-loaded check than Japanese readers may be used to.
3. The Current BOI Incentive Framework (Updated July 2025)
To understand the Power Confirmation Letter requirement in context, it helps to know the underlying BOI incentive structure. Based on the information currently available, the BOI updated its data center incentive criteria in July 2025 to differentiate corporate income tax holiday periods based on PUE (Power Usage Effectiveness — a metric where values closer to 1.0 indicate higher efficiency).
- High-efficiency DC (low PUE): up to 8 years of corporate income tax exemption
- Standard DC: up to 5 years of corporate income tax exemption
This PUE-linked tiering signals that Thailand’s policy is not just to attract data centers, but to attract efficient ones. The new ERC Power Confirmation Letter requirement extends that logic one step further: ensuring that efficient DCs are sited where the grid can actually serve them, and (in combination with Direct PPA) powered by renewables. For more on BOI incentives generally, see also our Thai SME Tax Incentives (2026) article.
4. The Direct PPA Scheme — A Path to 100% Renewable Sourcing
Alongside the new regulatory step, there is genuinely good news for data center operators: the Direct PPA scheme.
For decades, electricity transactions in Thailand have flowed primarily through the state-owned EGAT. The Direct PPA scheme launched in January 2026 (with an initial 2 GW allocation) allows electricity consumers to contract directly with renewable energy generators. Based on the information currently available, the eligibility criteria for data center operators are understood to be:
- Hold an existing BOI investment promotion certificate
- IT load of at least 50 MW per building
- Parent-company commitment to 100% renewable energy
- Submission of a 10-year electricity plan
The significance is straightforward. Hyperscalers like AWS, Google, and Microsoft maintain group-level RE100 commitments, and the ability to source 100% renewable power locally is a critical input to investment decisions. By creating a formal path to that outcome, Thailand has materially lowered the entry barrier for global cloud players.
By contrast, Japan has had liberalized retail electricity since 2016 and a growing corporate PPA market, but securing reliably 100% renewable supply remains constrained by the absolute volume of renewable generation and grid access. Thailand’s Direct PPA approach is interesting in the opposite direction — narrowing eligibility to large-scale DC operators in order to keep the program implementable.
5. Five Actions for Japanese Companies
1) Re-examine your DC project timeline
Until the formal ERC application process is published, the application-to-approval timeline carries new uncertainty. If your plan assumes a 3–6 month BOI approval window based on past experience, build in additional buffer for the ERC review step.
2) Reassess your power procurement strategy
Check early whether your project meets the Direct PPA eligibility criteria — particularly the “50 MW per building” threshold and the parent-level RE100 commitment. If the answer is yes, structuring procurement around Direct PPA also strengthens the narrative when applying for the ERC Power Confirmation Letter.
3) Re-verify site selection
Even within EEC priority zones, transmission capacity varies by location. Cross-checking site candidates against EGAT’s grid reinforcement progress is now a prerequisite for a smooth ERC review.
4) Confirm the “no retroactivity” treatment for existing projects
Based on currently available information, projects filed or approved before the effective date are understood to be outside the scope of the new requirement. Japanese companies with projects already in the pipeline should confirm — in writing — that their case sits cleanly within this carve-out.
5) Engage BOI, ERC, and counsel early
Precisely because the formal procedure is not yet public, early dialogue with authorities and counsel has unusually high value right now.
6. Practical Tips Japanese Companies Often Miss
Tip 1: Distinguish “DC business” from “in-house server room”
This article addresses cases where a company is applying for BOI incentives as a data center business. A Japanese manufacturer expanding the in-house server room of its Thai subsidiary for internal use is generally not the direct target of these new rules. That said, particularly large in-house facilities may be classified as a DC business depending on scale and operating model, so individual confirmation is advisable for sizable projects.
Tip 2: Convert your parent’s RE100 commitment into “evidence usable in Thailand”
Meeting the 100% renewable criterion under Direct PPA requires more than a parent-level policy statement — Thai authorities will expect documentary evidence. CDP responses, sustainability reports, and board resolutions, prepared in English (and ideally Thai), should be assembled in advance as part of the application package.
Tip 3: Close the gap between parent policy and local implementation
A growing concern for investors and counterparties is the gap between a Japanese parent’s RE100 pledge and the reality that overseas subsidiaries are still drawing primarily from fossil-fueled grids. Thailand’s Direct PPA scheme is a practical tool to start closing that gap.
Conclusion
At first glance, the ERC Power Confirmation Letter looks like another regulatory hurdle. In context, however, it is a coherent design choice: a government that is serious about attracting data center investment is also serious about ensuring that approved projects can actually be powered. Combined with the Direct PPA scheme, the realistic option for Japanese companies is now “an efficient DC, sited where the grid can serve it, and powered by 100% renewables.”
Now — before the formal procedures are finalized — is the right time to revisit your DC strategy and engage with experienced counsel.
Our firm advises on data center investment, BOI applications, ERC procedures, and Direct PPA contracts in Thailand. We support clients from the planning stage through contract review, leveraging both Japanese and Thai legal perspectives. Please feel free to contact us.
This article is for general informational purposes based on information publicly available as of April 2026 and does not constitute legal advice under Thai law. Figures and requirements cited herein are subject to change as official BOI and ERC announcements are released. For specific matters, please consult a Thai-qualified legal professional. Our firm works in collaboration with JTJB International Lawyers’ Thai-qualified attorneys.