Brazil launches new public consultation on storage regulation and adjusts rules to Law 15269

Brazil's National Electric Energy Agency (ANEEL) has taken another decisive step toward modernizing the Brazilian electricity sector by launching a new phase of regulatory discussions. Through the publication of Technical Note No. 03/2026, the agency has opened the debate to adapt current regulations to Law No. 15,269, enacted in November 2025, which formally recognized energy storage as an independent activity. This regulatory move complements the second phase of Public Consultation No. 39/2023, incorporating structural guidelines that define how batteries and other storage systems will operate, be charged, and paid for within the National Interconnected System (SIN). One of the most anticipated points for the market was the tariff definition.

ANEEL confirmed in its technical note that the so-called "dual tariff" for energy storage systems will remain in place. This means that batteries will not be exempt from paying for infrastructure usage, arguing that the new law does not exempt these assets from compensating for grid availability, as they use it in both directions. They will have to pay the Transmission or Distribution System Usage Tariff (TUST/TUSD) at two points:

• By consuming energy from the grid to charge their devices (as consumers).
• By injecting energy into the grid (like generators).

Furthermore, the regulation creates a new legal and operational figure: the Autonomous Storage Agent.

Previously, storage was framed under the rules of generation, but the new law eliminates the need for this parallelism.

How will they differ?

• Specific License: An exclusive authorization (outorga) will be issued for storage, with its own registration (SAE code) separate from the generation assets.
• No power limit: Unlike small distributed generation, the provision of autonomous storage service will require authorization from ANEEL regardless of its size, because there is no explicit legal exemption as in small capacity renewable sources.

The technical note clarifies that if centralized planning determines that a storage system is necessary for the Basic Grid infrastructure, it must be treated as a transmission asset and will be subject to mandatory auctions. However, Reversible Hydroelectric Power Plants (RHPs) are explicitly excluded from this transmission auction requirement, maintaining a separate regulatory regime. Meanwhile, projects that combine generation (such as solar or wind farms) with batteries at the same connection point ("co-located") will maintain efficiency incentives and are permitted to contract a System Usage Amount (SUA) up to 20% lower than the total installed capacity, recognizing the batteries' technical capacity to smooth injection peaks and optimize the use of the existing grid. On the other hand, in a decision that protects the end consumer, the regulation implements the provisions of Law No. 15,269: the costs derived from contracting batteries as capacity reserves (contracted power to guarantee system security) will be prorated exclusively among the generating agents. In other words, ANEEL ruled out the direct transfer of these costs to the tariffs of residential or industrial consumers.

Furthermore, new generation projects requesting access to the grid will be required to pay for this reserve if they do not meet minimum technical requirements for flexibility and storage.

Next steps ANEEL has divided the implementation into two standards: one specific to the licensing process and another transversal one that modifies existing regulations (such as REN 1000).

More complex issues, such as the integration of storage into the portfolios of Energy Marketers, have been postponed for a second cycle of the regulatory agenda.