Brazil's new transmission grid access policy seen reducing risks, lawyers say

Brazil’s new transmission system access policy (PNAST) brings clear rules and tends to reduce legal risks in the power sector, according to lawyers consulted by BNamericas.

Established through a federal decree in 2025, the PNAST introduces “access seasons,” a mechanism that replaces the first-come, first-served (queue) model with batch analyses, with selection based on technical and competitive criteria. The objective is to ensure the rational use of the grid, improve predictability for investors, and provide the sectoral planning process with more robust and realistic information on the future needs of the National Interconnected System (SIN).

The access seasons will occur at least twice a year and will include competitive processes only at the points in the network where there is more demand than flow capacity. The first must take place by October 2026.

The measure reflects a scenario of growing pressure on the system from new renewable power generation projects and large energy-intensive ventures, such as data centers and green hydrogen plants.

For Vitor Mello, a partner at Rolim Goulart Cardoso, there are no indications that the PNAST will trigger a multiplier effect of administrative or judicial challenges, although specific disputes are not ruled out, such as the one filed by Casa dos Ventos.

He understands that projects that already have an access opinion issued, as well as requests filed before the publication of the decree that established the PNAST, do not fall under the rules of the access seasons.

“Only in the event of a request for an increase in the already contracted MUST [Transmission System Usage Amount] will the PNAST rules be applicable,” he told BNamericas.

Mello emphasized that rule in art. 13, regarding the priority allocation of expansions resulting from the extraordinary review of the Electric Power Transmission Concession Plan (POTEE), applies to access requests registered with the ONS before the publication of the PNAST, as well as to consumer requests being processed at the MME.

“Thus, it does not seem reasonable to me that a project that already has an issued access opinion could be overtaken by another at a more incipient stage. If this hypothesis comes to pass, there are good arguments for filing an administrative and/or judicial challenge,” said the lawyer.

In the view of Felipe Zaratini, head of energy at Felsberg Advogados, the initial discomfort of some agents is expected in structural changes.

“Some players may feel harmed by the timing of the publication of the new procedure. However, the PNAST exists precisely to bring more legal certainty to a process that until now had been governed by the ‘luck’ of the timing of the access request,” he told BNamericas.

Zaratini pointed out that previous attempts at precautionary measures similar to those of Casa dos Ventos were not successful at Aneel. For him, the new policy established clear transition rules, which raises the level of technical requirements for the challenges.

The lawyer also believes that, in light of the transition rules and the regulatory deadlines in force, it is not plausible that projects with an access opinion already issued will be passed over in favor of others at an early stage.

“The next step after the issuance of the opinion is the signing of the CUST [Transmission System Usage Agreement], which already guarantees access to the grid,” Zaratini added.

(The original version of this content was written in Portuguese)