Brazil's ONS activates unprecedented emergency plan to cut excess solar generation

The National Electric System Operator (ONS) invoked, for the first time, its Emergency Management Plan for Energy Surpluses on Sunday, a response to an unusually high supply of electricity caused by intense solar generation and low demand during a holiday weekend. The surplus threatened grid stability and could have triggered automatic shutdowns. Under the plan approved by ANEEL in November 2025, ONS ordered the reduction of output from small and micro solar generators, as well as small hydro, biomass and wind facilities that are connected to distribution networks.

ONS officials said they will continue to monitor the system, issue alerts up to seven days in advance and coordinate with distributors, which will select generators for curtailment through a rotating schedule to avoid repeatedly affecting the same plants. A spokesperson added, "We remain attentive to the new electro‑energy reality and are working to ensure the safety and efficiency of the system in line with current network procedures." The action aims to keep generation and consumption balanced and prevent potential blackouts.