OttawaOntario’s power grid is feeling the strain after this week’s heat wave pushed electricity use to its second highest peak since 2013. The first three days of this week have been among the top 10 of this year for power consumptionCBC News · Posted: Aug 13, 2025 5:50 PM EDT | Last Updated: 38 minutes agoDemand for power increases as Ontario residents look to cool off this summer (Sean Kilpatrick/the Canadian Press)Ontario’s power grid is feeling the strain after this week’s heat wave pushed electricity use to its second highest peak since 2013. Demand peaked near 25,000 megawatts on Monday as residents and businesses turned on cooling systems to escape the heat, according to the Independent Electricity System Operator (IESO), the Crown corporation responsible for Ontario’s power grid.Monday’s peak demand was the second highest this year, following June 24. Sunday and Tuesday were the sixth and seventh highest demand days this year respectively.”Ontario is a summer-peaking province,”� said Joseph Ricasio, a senior manager in charge of system operations at IESO. “It’s really hot outside and everyone wants to keep cool. Everyone wants to be comfortable and crank their AC up.”This week’s spike follows a stretch of hot days and warm nights across much of the province that have kept cooling systems running for longer.The price of staying coolIn Ottawa, the recent stretch of hot days has been felt inside Benson Mutalemwa’s non-alcoholic beverage shop on Bank Street.”Customers will come in and the first thing they usually say on a hot day is, ‘Oh, it’s nice and cool in here,'” he said.Benson Mutalemwa is the owner of Knyota, a local non-alcoholic drink shop in Ottawa that uses a lot of electricity to keep cool. (Josiane N’tchoreret-Mbiamany/CBC)While customer comfort is a priority, Mutalemwa also thinks about the drinks on his shelves.”Because we’re selling beverages, we can’t have them experience heat stress,” he said. “It could impact the product and how it kind of comes across. So we like to keep the room cool so that our drinks can last longer and taste the best.”This summer’s heat has resulted in the highest hydro bills he’s received in three years.”We don’t have gas heating or gas cooling, so everything is electric,” Mutalemwa said. “Our utility bills have definitely gone up this summer.”Planning for a power-hungry futureIn the coming decades, Ontario’s demand for electricity is not just expected to peak during summer heat waves, it is forecast to grow dramatically.”Grid transformation is happening now and it’s happening quickly,” said Ricasio. “By 2050, we are forecasting the demand to increase by 75 per cent.”The shift is being driven in part by more devices and systems running on electricity, Ricasio said.The Independent Electricity System Operator (IESO) says they make sure that the power grids are as resilient as possible to keep up with the extreme heat demands. (Darren Calabrese/The Canadian Press)IESO works to keep the grid operational through peak demands with regular training for staff, Ricasio said. “We have a lot of simulator sessions that are focused on these extreme events.” Being prepared also means keeping lines of communication open with nearby provinces, Ricasio said. “We talk fairly closely with our neighbours when there’s heat demands,” he said, so “we can share our energy to help each other out.”On the local front, Hydro Ottawa said it keeps a close eye on the system.”While we anticipate a rise in electricity consumption due to air conditioning and other cooling measures, our system is designed to handle these peak loads,” a spokesperson said in a statement. “Should any issues arise, our crews are ready to respond quickly.
Ottawa heat wave drives electricity demand toward a summer peak
