On Thursday afternoon, a severe power outage occurred in the northern Brazilian states of Rondônia and Acre, as well as in parts of Mato Grosso in the center-west. The entire state of Acre was plunged into darkness, leaving more than 218,000 residents without electricity for three hours.
While power supply was largely restored by 6 p.m. yesterday, Porto Velho, the capital of Rondônia, struggled with an unstable network for another two hours.
Energisa, the company responsible for supplying electricity in Acre, attributed the outage to “an external event in the national electricity grid.” Brazil’s electricity grid operator ONS reported a failure in the Madeira complex’s direct current transmission system and a loss of “230 kV” in the network connecting Acre and Rondônia to the national grid.
The ONS has not yet provided a clear explanation for the incident that led to the systems going offline, but has promised to provide a full report on the incident at a later date.
The Ministry of Mines and Energy, together with the ONS and the regulator Aneel, has set up a situation room to closely monitor the situation. Despite the outage, the ministry assured that “the operating conditions of the Brazilian system remain reliable throughout the national territory.”
The Brazilian report has shown that government officials are increasingly concerned about the future of Brazil’s energy supply. Financial problems at energy companies, the impact of climate change on Brazil’s hydropower-dependent energy system, and rising demand for electricity all contribute to the uncertainty.
In 2023, Brazil experienced a series of heatwaves followed by heavy rains, causing numerous short power outages. In August 2023, 26 of Brazil’s 27 states were without power due to a massive blackout. The ONS published a report two months later concluding that the blackout was caused by solar and wind power generation output that was “far below” expectations.
The high demand for electricity in the early evening hours due to the intense heat also posed a challenge for the national power grid and was one of the main causes of the frequent outages in the southeast, the financial center of Brazil.
As reported in our Brazil Daily newsletter of 21 August, the ONS has warned the government to introduce preventive measures to avoid supply problems during peak hours, which are usually between 6pm and 7pm, when solar power generation drops sharply.
