Intense Ontario heat heaps pressure on electrical grid, approaching 10-year high

Ontario’s energy minister says sweltering temperatures are pushing electricity usage up to record levels across the province.

Speaking on Wednesday, as temperatures ranged between 30 C and 35 C, Stephen Lecce promised that Ontario’s electrical grid is ready for the strain.

“We are confident in our system,” Lecce, who was appointed energy minister in an early June cabinet reshuffle, said.

“We have taken action to grow and scale up our clean energy generation. But it is a reminder for us all that we have a role to play too in how we can conserve electricity during these high-peak times within our summers.”

Lecce’s office said demand was expected to peak at around 24,000 megawatts on Wednesday, which would be the highest peak since 2013, with the exception of the summer of 2020, when Ontario had to change the energy rules for industry as the pandemic added extra electrical strain.

Between 2 p.m. and 3 p.m., energy usage was at 22,300 MW in Ontario.

“Today, on the hottest of summer days so far in 2024 and one of the highest days of energy usage in a decade,” Lecce said.

The high energy use comes as Ontario swelters under an extended heat wave, which has prompted warnings from Environment Canada.

Jennifer Smith, a national warning preparedness meteorologist with Environment and Climate Change Canada, said a heat wave this intense “has rarely been observed this early in June,” and is similar to the worst heat waves usually seen in July and August.

The high humidity and relatively high nighttime temperatures are making this week’s weather especially gruelling, Smith said Wednesday during a news conference.

“People are not able to cool off for an extended period of time,” she said. “It will be a muggy, hot few days for Eastern Canada.”

The heavy heat has pushed more homes and businesses to switch on their air conditioning, increasing demand. When demand in Ontario spikes, natural gas plants are turned on to help with the load.

Around 3 p.m., just under 20 per cent of the province’s electricity was being powered by natural gas.

Ontario Green Party Leader Mike Schreiner said natural gas was not just a backup for the province but a crutch.

“Having fossil fuel gas as an emergency backup may make sense but that’s not what the Ford government is proposing,” he said.

“They’re running these gas plants 24-7 every day, which means more pollution and higher electricity costs for the people of Ontario.”

Lecce said that, while the aim was to decarbonize Ontario’s electrical grid over “decades,” he didn’t want to take “premature” measures that could increase costs or cause blackouts.