air conditioner

Lower temperature highs in the province in July has coincided with lower electricity usage. (Jen Keiller/CBC)

While temperatures are expected to rise Tuesday in Ottawa, cooler temperatures so far this summer may be behind a dramatic drop in electricity use in Ontario.

​Summer months tend to see a peak in electricity use across the province, as more homeowners turn on their air conditioners during heat waves, according to Martine Holmsen, a spokeswoman with Independent Electricity System Operator, the Crown corporation responsible for operating the electricity market in the province.

She said demand reached a peak of 25,000 megawatts during a heat wave the week of July 17 last year, but was about 25 per cent less last week.

"The temperature was only 23 degrees Celsius, so most of us probably weren't even turning on our air conditioners," said Holmsen. "I just opened my windows and let the air come in, so the demand was 7,000 megawatts less."

Environment Canada data from Ottawa International Airport says Ottawa's average high temperature has been about two degrees Celsius lower in July this year than in the previous year.

Ottawa resident Emery Collete said he's noticed the difference, and hasn't needed to have his air conditioner on constantly as he said he did last summer.

"Hasn't been that warm," he said.

Temperatures in Ottawa and much of eastern Ontario are expected to rise to highs above 30 C on Tuesday, however, and some regions, including Cornwall and Prescott-Russell, are under heat warnings.

Collette said if his home gets too hot, he won't hesitate to rely on his air conditioner.

"If you need it you need it," he said.

The temperature is expected to dip down to a high of 25 C in Ottawa Wednesday as clouds roll in.

Poll question