On January 20, 2026, and in line with the National Data Center Plan 2024–2030, as well as with the recent amendments to the Regulations of the Environmental Impact Assessment System (“SEIA”), the Executive Directorate of the Environmental Assessment Service (“SEA”) published the document entitled Evaluation Criterion: Observance of the evaluation criterion in the SEIA – Introduction to data center projects (the “Guide”).

The purpose of the Guide is to provide a general introduction to data center projects, describing their main components, works and equipment, the associated environmental impacts, and certain considerations for the preparation of prevention and emergency plans. It also establishes the conditions under which these projects must be mandatorily submitted to the SEIA.

In particular, the Guide describes the different types of data centers and their potential locations, as well as the works and equipment typically involved, which allows:

(i) to assess whether a project must be submitted to the SEIA;
(ii) to identify potentially applicable Sectoral Environmental Permits (“PAS”); and
(iii) to recognize the factors that may generate environmental impacts.

As data center projects do not have a specific entry typology under the SEIA, their assessment must be conducted on a case-by-case basis, considering the components, works or actions associated with their execution. In this regard, the amendment to the SEIA Regulations published in the Official Gazette on January 21, 2026, is particularly relevant.

The Guide provides indicative guidance on the main conditions that could justify submission to the SEIA, including:

• the existence of associated electrical infrastructure, such as high-voltage transmission lines exceeding 23 kV with a length greater than 2 kilometers, or emergency and backup generators exceeding 3 MW; and
• (ii) the management of hazardous substances, either through the production, disposal or reuse of flammable substances in certain quantities, or through storage volumes equal to or exceeding 1,000 tons.

Additionally, the Guide identifies, on a referential basis, the potential environmental impacts that data center projects may generate at different stages, which will depend on the territorial context and the environmental characteristics of the affected area. It also includes an indicative list of PAS that may apply, together with the circumstances that would justify their obtainment.

The Guide will enter into force upon publication of its extract in the Official Gazette and will be mandatory for projects or activities submitted to the SEIA from that date onward. Projects currently under evaluation may consider the Guide on a voluntary basis.