As heat wave-ravaged Ontario residents cranked up their air conditioners amid assurances there is plenty of electricity for all, environmental groups warned that the focus should be on energy conservation.
Millions of people in Quebec and Ontario are coping with the scorching heat wave that's pushed temperatures into the mid-30s and humidex readings into the 40s.
In Montreal, a radio station helped several dozen locals cool off in a creative way without the use of air conditioning - with a snowball fight.
Ontario residents trying to keep cool put so much pressure on the power grid that consumption surpassed the expected peak in the early afternoon, and then surpassed the revised expected peak. By 5 p.m. consumption hit 25,048 megawatts.
The record in Ontario, set on Aug. 1, 2006, is 27,005 megawatts.
Ontario's Independent Electricity Operator said the system could handle that demand - largely due to a dramatic decrease in demand from the province's manufacturing sector, which shed nearly 300,000 jobs during the economic downturn.
Environmentalists said the focus shouldn't be on abundance of supply.
"The Ontario government is one of the leaders in terms of promoting energy conservation, but it's certainly putting more effort into investing in new supply than it is into investing in conservation and efficiency," said John Bennett, head of the Sierra Club.
He said the province needs to change laws to ensure only energy-efficient products are sold on store shelves, and provide stronger incentive programs to switch to more environmentally friendly items.
Ontario Energy Minister Brad Duguid said the province is encouraging residents to conserve, but also touted plans to generate more electricity, including purchasing nuclear power plants and producing clean energy.
He said the government has brought 8,000 megawatts of power into Ontario over the last seven years, in efforts to prevent another major blackout like the one in August 2003 that left 50 million people in eastern North America in darkness.
"We still have work to do to build what I would call a culture of conservation in the province," Duguid said.
"We're determined to get there but it's going to take time to shift attitudes and to shift behaviour."
Hydro-Quebec said summer demand typically hovers around 22,000 megawatts, as the province tends to consume more energy during winter deep freezes.
The heat saw health emergency calls spike in both Toronto and Montreal. Ambulances in Toronto received 51 per cent more complaints about breathing problems Wednesday over the same time last year.
EMS officials said fainting calls have jumped 39 per cent, and total call volume for ambulances was up about 13 per cent over 2009.
The ambulance service for Montreal and Laval has seen a 25 per cent spike in emergency calls since Monday.
Many of the extra calls are for people suffering from dizziness, respiratory problems, heart conditions and reports of fainting, service spokes-man Benoit Garneau said.
The organization responds to about 800 calls each day, but answered 1,000 on both Monday and Tuesday.
"We should do around 1,000 calls again today," he said, adding the service has beefed up its ambulance fleet by 10 per cent to handle the extra workload.
Environment Canada says residents will get a short reprieve from the sky-high temperatures during a thunderstorm Friday, but the mercury will quickly climb again on the weekend and next week. It says early forecasts show Ontario and Quebec will experience higher than normal temperatures until August.
Queen's University professor Harry McCaughey, who studies climate change, says there will be more frequent extreme heat waves and cold snaps in the future and provinces should expect energy consumption to rise when the weather changes.
He suggests conservation is the most important way to control consumption.
"We haven't yet got serious about this and it's time that we did as a society," he said.
The Montreal snowball fight began with an ice-distribution company delivering more than 225 kilograms of crushed ice in bags. The bags were emptied onto the grass in Old Montreal, where handfuls were scooped up by passersby and tossed in all directions.
Several people even jumped head first into the pile of crushed ice.
Richard Yeghiaian of Iceman Inc., who supplied the ice, says business has picked up quite a bit since the heat wave began.
"Once it hits 30 degrees, it goes crazy," he said.
Mark Bergman of Virgin 96 radio station said when he found out there would be record-breaking temperatures on Wednesday, the station decided to act.