ONS Director-General Marcio Rea supports the creation of new rules for the micro and mini distributed generation sector to enhance control over energy injection into the grid.
The accelerated expansion of distributed generation (DG), primarily driven by photovoltaic solar technology, has reached a point requiring an urgent update to the management mechanisms of Brazil’s electricity system. The National Electric System Operator (ONS) has been signaling the need for an “organizational brake” to balance the growing supply from this modality with the actual absorption capacity of transmission and distribution networks.
During a discussion on the challenges of the energy transition, ONS Director-General Marcio Rea highlighted that the exponential growth of micro and mini distributed generation (MMDG) is already imposing significant operational challenges. The central concern lies in system security amidst the high volatility of a grid that is becoming increasingly decentralized and dependent on variable renewable sources.
Regulation and New Operating Models
The ONS, in collaboration with the Aneel (National Electric Energy Agency) and the MME (Ministry of Mines and Energy), is working to establish guidelines for a more intelligent dispatch of energy resources. Currently, the operator already uses an emergency plan for generation curtailment when system load is insufficient to absorb the injected energy, especially on low-consumption days like weekends.
To mitigate these disruptions, the agency has proposed a regulatory sandbox involving distribution companies, testing the DSO (Distribution System Operator) model. The intention is to transform grid management, allowing the ONS greater real-time visibility and control over distributed energy resources, integrating them more efficiently into centralized dispatch.
“What is needed is control, whether through homes already having batteries or through regulation that allows remuneration for these individuals, homeowners with their photovoltaic systems. DG has grown a lot, and it’s difficult to stop it now; it’s not easy. The first thing that needs to be done is a regulation to put an organizational brake on it.”
The Role of Storage in Grid Balancing
One of the key solutions pointed out by the director is incentivizing energy storage through batteries. The strategy is to retain surplus energy generated during low-demand periods for use during peak hours, thus avoiding the waste of clean energy and reducing pressure on the grid. The government plans a specific auction for storage systems later in December, a measure seen as crucial for stabilizing supply.
In addition to batteries, the implementation of price signals—where remuneration varies according to system needs—appears as a tool to encourage conscious consumption and residential storage. According to Rea, this integration between distributed generation and storage systems is essential not only to prevent instabilities but also to enable new consumption demands, such as the installation of large data centers that require high security and energy supply reliability.
The future of the electricity sector now depends on precise coordination between regulation and technology. While the ONS works to prevent overloads, the expectation is that with new rules and investments in transmission infrastructure, the country will be able to absorb the growth of renewable sources without compromising the reliability of the national system.