Mai 05. 2026

Brazil Publishes Guidelines for the Access Seasons under the National Policy for Access to the Transmission System – PNAST

Authors:

On April 27, 2026, MME Normative Ordinance No. 129, dated April 24, 2026 (the “Ordinance”) was published in the Official Gazette, setting forth the guidelines for the Access Seasons provided for in Decree No. 12,772/2025 (the “Decree”), which established the National Policy for Access to the Transmission System (“PNAST”).

The PNAST changed the rules for generators and consumers to access the transmission system, replacing the former first-come, first-serve rule by a competitive process called an Access Season.

The Ordinance mainly regulates:

The registration process for interested agents;
The mechanism for calculating and disclosing available capacities in the connection points;
The bid award criteria and the allocation of the funds arising from the Access Seasons; and
The possibility of adopting Access Seasons as a preliminary stage of energy and capacity reserve auctions where the transmission capacity margin is a requirement to bid.

Registration of Interested Agents

Any agents interested in permanently accessing the basic grid or increasing their contracted capacity amount (“MUST”) will need to register with the National Electric System Operator (“ONS”) during the period defined for each Access Season.

The ONS will publish the registration instructions within 30 days prior to the commencement of the registration period.

After the registration period, the ONS will, within 15 days: (i) confirm the acceptance of the requests; (ii) reject the requests that do not comply with the instructions; and (iii) publish the list of accepted requests.

Calculation and Disclosure of Available Capacities

The Energy Research Company (“EPE”) and the ONS will jointly prepare a Technical Note on the Methodology, Assumptions and Criteria for the calculation of the remaining capacity in the basic grid busbars for each Access Season.

The Technical Note will be submitted to the Ministry of Mines and Energy (“MME”) and published on the EPE and ONS websites within 30 days prior to the commencement of the registration period for each Access Season.

After the registration period, the ONS will: (i) forward to the EPE a list containing the candidate busbars and the respective capacity amounts requested by the agents during the registration for purposes of assessment of the minimum global cost (i.e., confirmation that the connection to the relevant access points is the most cost-efficient connection solution), and (ii) consult the transmission concessionaires regarding the physical feasibility of connection at the candidate busbars.

The concessionaires will have 15 days to respond, and the candidate busbars whose connection is deemed unfeasible will not be qualified for the Access Season.

The ONS will be responsible for calculating the remaining capacity at the candidate busbars based on the reference cases for electrical simulations of the Medium-Term Electrical Operation Plan of the National Interconnected System (“PAR/PEL”) for each year of the five-year PAR/PEL.

For this calculation, ONS will consider the transmission facilities whose estimated commercial operation date does not exceed the five-year PAR/PEL and that fall under one of the following categories:

Granted by the National Electric Energy Agency (“ANEEL”) by the date of the ordinary meeting of the Electric Sector Monitoring Committee (“CMSE”) held in the last month of the registration period;
Included in the Electric Power Transmission Concession Plan, Expansions and Reinforcements – Basic Grid and Other Transmission Facilities (“POTEE”) in effect in the last month of the registration period, which will be considered only in the last year of the applicable PAR/PEL. On an exceptional basis, the MME may include in the POTEE facilities whose estimated commercial operation date exceeds the five-year PAR/PEL, where the execution of the Transmission System Use Agreement (“CUST”) is a requirement for the bidding of the project; and
Arising from sectioning contemplated in valid access opinions.

The calculation of the remaining capacity at the candidate busbars will consider the transmission facilities planned up to December 31 of each year of the applicable PAR/PEL.

In the calculation of the remaining capacity, the ONS will consider the following consumers and generation projects:

Those in commercial operation; and
Those that hold, up to the end of the registration period, one of the following documents:

a) CUST;
b) Distribution System Use Agreement (“CUSD”);
c) Valid access opinion issued by the ONS; or
d) Requests admitted by the ONS filed by the end of the registration period.

Furthermore, the ONS will also consider generation projects that were winners of energy and capacity reserve auctions where transmission capacity margin was a selection criterion and held by the end of the registration period (even if their estimated commercial operation dates exceed the five-year PAR/PEL).

The ONS and the EPE will publish the Technical Note on the Remaining Capacity Quantities of the National Interconnected System on their respective websites within 30 days prior to each Access Season.

Said Technical Note will indicate, for each candidate busbar, subarea and area of the National Interconnected System:

The remaining capacity, in megawatts (MW);
The transmission facilities that are considered in the calculated remaining capacity;
The total capacity amount requested by the agents, in MW; and
The need to hold or not to hold the Access Season.

Competitive Process, Premium Payment and Allocation of Funds

A competitive process will be held to access the qualified busbars where the capacity amount requested by the agents exceeds the remaining capacity.

The admitted agents in the registration period will be able to participate in the competitive process.

The main classification criterion of the competitive process will be the highest premium offer, expressed in BRL/kW (Brazilian reais per kilowatt) of requested capacity. The premium:

Must be paid in full by the winning bidder prior to the issuance of the Preliminary Access Diagnosis;
Does not waiver or replace the Transmission System Use Charges (“EUST”) nor the financial guarantees required by the current regulations as a requirement for the execution of the CUST; and
Will not be subject to refund.

The bid bonds posted by non-winning bidders will be returned after the disclosure of the result of the competitive process.

Additional classification criteria may be considered, provided that, within a certain range in relation to the best offer: (a) there is a reduction of the operational costs of the National Interconnected System greater than that one with the highest premium, and (b) it preserves the competition for access, system security and risk perception.

The funds paid by the winning bidders will be allocated to the reduction of the electricity tariffs. These funds will be considered in the ONS budget and will be mandatorily used to reduce the EUST.

Preliminary Access Diagnosis and Transmission System Use Contracting

The ONS will issue a document called Preliminary Access Diagnoses for:

Winning bidders of the competitive process, subject to payment of the premium;
Agents admitted at qualified busbars where the remaining capacity is sufficient to meet the requested capacity (no need of a competitive process); and
Winning bidders of energy and capacity reserve auctions where the transmission capacity margin was a selection criterion.

Agents with the Preliminary Access Diagnosis must execute the respective CUST, subject to the submission of the financial guarantee as per applicable regulations (in the amount equivalent to 40 months of the EUST). ONS will then return the bid bond or issue a release certificate.

Agents that fail to pay the premium or execute the CUST will be subject to: (i) loss of the capacity awarded in the Access Season; (ii) enforcement of the bid bond; and (iii) prohibition from participating in the two subsequent Access Seasons.

Transitional and Final Provisions

Winning bidders of energy and capacity reserve auctions held prior to the date of publication of the Ordinance must register in an Access Season for the purpose of issuance of the Preliminary Access Diagnosis, in which case they will be considered in the calculation of the remaining capacity. Thus, such requirement is applicable to the winning bidders of the Capacity Reserve Auctions held in March of this year.

Energy auctions and capacity reserve auctions where transmission capacity margin is a selection criterion may adopt the Access Season as a preliminary stage. In any event, the winning bidders will have to register in a subsequent Access Season to obtain the Preliminary Access Diagnosis. Therefore, the upcoming first BESS Reserve Capacity Auction may adopt these new rules of the Access Season.

The result of the Access Seasons may support and guide the EPE in the preparation of the transmission system expansion planning studies, within the scope of the POTEE, to identify system expansion needs.

The ONS will submit proposals for the adaptation of the ONS Grid Procedures to incorporate the provisions of the Ordinance.

Transmission Delay Risk Allocation

The Ordinance provides that the agent with an executed CUST undertakes the risk of delay in the construction of the transmission facilities necessary for its connection obtained in the Access Season, which prevents the commencement of its commercial operation, waiving its rights to reimbursement or financial compensation. In other words, the EUST will be due and payable by the agent as of the date indicated in the CUST even if the agent is not using the contracted capacity as a result of a delay in the construction of the transmission facilities by the transmission concessionaire.