Outage affects three Brazilian regions

Brazil's national grid operator ONS announced on Monday (Jan 19) that restrictions in the transmission of energy from the North and the Northeast to the Southeast, coupled with a higher demand during peak hours, led to a reduction in the electrical frequency as well as power outages in several states in the South, the Southeast and the Central-West. The issue was detected after 02:55 p.m. (GMT -3).

The frequency slipped from 60 to 59 hertz. As a result, over ten energy-generating units were shut down, with a total output of 2,200 megawatts. Among the power generators temporarily closed is the Nuclear Center of Angra dos Reis, in Rio de Janeiro, where the nuclear power plants of Angra 1 and Angra 2 are located, as well as the under-construction Angra 3.

“The reactor was deactivated thanks to the work of the equipment protecting it. The cause was ascertained as being a reduction in the frequency of the SIN [National Integrated System],” says a note from Eletronuclear, the state utility which serves the complex in Angra dos Reis.

The blackouts also hit operations in São Paulo's metro system. Rio de Janeiro's utility Light declared its number-one priority was maintaining the availability of essential services, from supplying hospitals and large-scale clients to keeping transport (train and metro) and water supplies uninterrupted.

ONS also reported that it adopted measures to ensure the electrical frequency is raised back to normal levels, with “an impact of less than 5% to the system's capacity.”

Translated by Fabrício Ferreira