Why Canada’s power grid is not ready for extreme weather

Experts at the University of Toronto say there are concerns if Canada’s power grids can face the severe weather conditions that are becoming more common.

This is part one of a two-part report on the resiliency of Canada’s power grids in the face of climate change and increasing extreme weather.

Downed power lines. Flooded substations. Fire-damaged poles.

While Canada grapples with another intense wildfire season, there are new concerns about whether the country’s electricity grids can keep the power on during more frequent and more severe weather events.

“The grid that we have today has not been designed for accommodating such extreme scenarios,” said Ali Hooshyar, the director of the Grid Modernization Centre at the University of Toronto. His centre runs tests using real-time grid simulators, and he says power grids are designed to accommodate the failure of only one component at a given moment.

“The problem with extreme weather conditions is that at a given time, all of a sudden, you may lose several components,” Hooshyar explained.

With the challenge of severe weather growing and electricity demand reaching new heights, experts and industry insiders say that they’re concerned about meeting Canada’s energy needs before the demand outpaces the progress.

What are the threats to the electric grid?

A report in April from The North American Electric Reliability Corporation (NERC) found that most provinces are at risk of power shortfalls during extreme weather conditions.

The independent industry watchdog has also projected over half of North America will be at risk for blackouts due to a surge in electricity demand and retiring fossil-fuel power plants in the next five to 10 years.

“We don’t have the kind of margins we may have had in the past to be able to weather through unexpected highs in demand or lows in resource performance,” said Mark Olson, manager of reliability assessments at NERC.

Looking ahead to 2033, NERC’s forecast shows Quebec and Nova Scotia will be particularly vulnerable to outages.

Quebec could face up to a 10 gigawatt energy deficit due to projected demand growth, especially during extreme winter conditions.

By comparison, 10 gigawatts is almost double the capacity of Hydro-Quebec’s Robert‑Bourassa generating facility, the largest hydropower generation facility in North America, which generates half the electricity consumed in Quebec.

Nova Scotia had instances of insufficient energy resources across all 12 years in the study.

“More shortfalls can occur during these extreme weather events,” said Olson, “and it poses a serious concern for reliability.”

According to Electricity Canada, a national group representing the electricity sector, the 10 most significant extreme weather events in the country between 2013 and 2023 caused nearly 20 million customer electricity interruptions.

Of those events, eight occurred in the second half of the 10-year period.

Part of what makes Canada’s power grids particularly vulnerable, Hooshyar explained, is how old its infrastructure is in some areas of the country, with parts dating back over a century.

“We were basically one of the pioneers, [but] because we were one of the pioneers, we are dealing with the challenges of aging infrastructure earlier than many other areas in the world.”

What’s at stake?

The types of severe weather challenges are unique across Canada’s vast landscape, but from heat waves to cold snaps and wildfires to storms, extreme conditions are reported nationwide and the consequences of those events can be catastrophic.

The B.C. Coroners Service confirmed that there were 619 heat-related deaths in the devastating 2021 Western heat dome.

Two years later, during the hottest summer on record, Statistics Canada data shows B.C. residents turned to air conditioning to beat the heat. In July of 2023, the province consumed nearly eight per cent more electricity than the July average from 2016 to 2022.

Wind is the biggest problem in parts of Atlantic Canada. Nova Scotia Power reports that in the last five years, wind gusts over 80 km/h were up 33 per cent from the five years prior.

The biggest causes of outages in the province are trees and branches damaging power lines during storms. Severe weather accounted for over 1,000 power outages across the province in 2024.

Severe weather also comes with a hefty price tag.

In May 2022, a powerful windstorm called a “derecho” pummeled southern Ontario and Quebec, leaving eight people dead and hundreds of thousands of people without power. Many customers were still in the dark nearly two weeks after the storm.

The event cost a total of $1 billion in insured damage, much of that affecting utilities like Hydro Quebec which said derecho damage to its power grid cost $70 million.

The challenge of increasing electricity demand

While climate change-driven extreme weather is a growing problem for Canada’s grids, the demand for electricity is climbing, too, adding more pressure on an already-vulnerable system.

“If the weather is going to continue in this way and continue to be challenging, we’ll continue to look at how we adapt to it,” said Francis Bradley, president and CEO of Electricity Canada. “But that will be against the backdrop of increasing demand for electricity.”

Those added demands include the consequences of increased electrification such as electric vehicles and heat pumps, growing populations, and power-hungry data centres that power artificial intelligence cropping up across the continent.

For example, IESO, which monitors and operates Ontario’s power system, projects the province’s electricity demand to grow 75 per cent by 2050, and Manitoba expects its energy demand could more than double in the next 20 years.

“I’m not concerned about tomorrow, but when I project ahead five or 10 years, yes, I am concerned about our ability to move fast enough, to be able to bring on the new technologies and bring on the new sources of clean energy that we’re going to need because the demand is increasing,” Bradley said.

“There’s an inevitability to this.”

• Part two: The race to make Canada’s power grids more resilient – before it’s too late

Rukshar Ali is a multi-platform journalist from Calgary and a recipient of the Sachedina - CTV News - Fellowship.