Electricity demand on Brazil’s National Interconnected System (SIN) fell by 10.9% during the Brazilian national team’s FIFA World Cup victory over Paraguay on Friday. According to the National Electric System Operator (ONS), demand dropped by about 9.4 GW between 4:50 p.m. and 5:20 p.m., a pattern the operator says is typical during major sporting events.

The ONS expects an even steeper decline during Brazil’s Round of 16 match today, forecasting a 15% to 20% reduction in electricity demand because the game will take place during business hours. The operator said it has reinforced grid operations through enhanced monitoring, dispatch of fast-ramping power plants, and coordination with generators and transmission companies.

Bárbara Rubim, chair of the board at the Brazilian solar energy association ABSolar, said the phenomenon has been well understood for years. “The challenge is not a lack of information but adapting the system to a reality that has already changed.”

She noted that during the 2022 FIFA World Cup, electricity demand dropped by about 12.6 GW during one of Brazil’s matches before rebounding by 7.7 GW within 30 minutes after the final whistle. A similar pattern occurred during the 2018 World Cup, when demand fell by about 8.6 GW during Brazil’s match against Belgium.

Rubim said the challenge has grown as Brazil’s generation mix has changed. Installed solar capacity has increased from about 6 GW in 2018 to more than 35 GW today, while wind capacity has expanded from around 15 GW to about 70 GW.

She said the growing share of renewable and distributed generation requires a more flexible electricity system capable of responding quickly to rapid changes in demand. Battery storage and the operational flexibility of hydropower plants will become increasingly important, she added.

According to Rubim, the focus should be on modernizing grid operations rather than blaming solar generation. “Brazil’s power system must evolve at the same pace as the changing energy mix,” she stated.

The ONS expects the familiar pattern of a sharp demand drop at kick-off followed by a rapid rebound after the match to repeat during Monday’s Round of 16 game.