London Hydro Sees Record High Demand As London Experiences Heat Wave

For Immediate Release: June 24, 2025

London, ON 

As the region faces an extended heat wave, London Hydro is experiencing one of the summer’s first days of high electricity demand. Yesterday, London Hydro saw a peak demand of 716MW, the highest recorded peak in the last 10 years.

London Hydro is expecting an even higher demand today as many Londoners are turning to air conditioning and fans to stay cool in the soaring temperatures. Despite the surge in usage, London Hydro reports that the system is stable and performing reliably.

“Extreme heat can put added stress on the system, but thanks to strong planning and reliable infrastructure, London’s grid is performing well,” said Ysni Semsedini, CEO of London Hydro. “Our team continues to monitor demand in real time to ensure we can respond quickly if conditions change.”

London Hydro’s peak electricity demand typically occurs between 4 p.m. and 6 p.m. when residential and commercial energy use overlap. London Hydro is encouraging customers to help manage strain on the system by shifting non-essential electricity use—like laundry, dishwashing, or EV charging—to earlier or later in the day when possible.

Customers can also take simple steps to reduce energy use and stay cool:

• Keep blinds and curtains closed during the hottest parts of the day
• Set thermostats a few degrees higher when home and even higher when away
• Use ceiling fans or portable fans to support cooling
• Avoid using ovens and stoves during peak hours

“We want to thank Londoners for doing their part to stay energy-smart during this heat wave,” added Semsedini. “Even small actions, when multiplied across the city, can make a big difference.”

London Hydro will continue to monitor system conditions and provide updates as needed. To learn more about energy-saving tips or sign up for tools to track your usage, visit www.londonhydro.com.