Record electricity demand hits London during heat wave, but grid holds up

As scorching temperatures persist across the region this week, London Hydro says electricity usage has surged to the highest level in a decade.

Demand hit a peak of 716 megawatts on Monday, an amount not seen in more than 10 years. And with more hot days in the forecast, the utility could see even more pressure on the grid, officials say.

"Extreme heat can put added stress on the system," said Ysni Semsedini, CEO of London Hydro. "Thanks to strong planning and reliable infrastructure, London's grid is performing well."

The most significant spikes tend to come in the late afternoon when residents are returning home, businesses are still open, and energy use from air conditioning, fans, appliances and EV chargers all converge, said Jac Vanderbaan, the vice president of operations and planning at London Hydro.

"We typically see the peak between 4 and 6 p.m.," Vanderbaan said. "That's when people are cranking up the air conditioning, starting dinner, and plugging things in."

Despite the strain, Vanderbaan said the system has been handling the load well, thanks in part to conservation efforts, demand management, and the growth of solar energy systems.

To help manage usage and prevent future stress on the system, London Hydro is asking customers to delay non-essential activities such as laundry, dishwashing and electric vehicle charging until after peak hours. Other energy-saving tips include:

• Keeping blinds and curtains closed during the day.
• Setting thermostats slightly higher when home, and even higher when away.
• Using ceiling or portable fans.
• Avoiding the use of electric ovens or stoves during peak hours.

Even small measures can add up, Semsedini said.

"When multiplied across the city, those little actions really do make a difference."

As climate patterns shift, the utility is planning ahead to ensure the grid can withstand more frequent extreme weather events, Vanderbaan said.

"We're looking 15 to 20 years out," he said. "We're making sure we have the generation, transmission and distribution capacity to meet future demand."

London Hydro will continue monitoring conditions and provide updates as needed throughout the heat wave. Customers can learn more and track their energy usage at londonhyrdo.com.