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Impacts on demand during current heatwave

July 9, 2020

This week’s heatwave shows again that weather is the biggest factor determining electricity demand. A couple interesting insights from the past few days:

Daily peak demand has climbed higher and higher each day as Ontarians keep the air conditioning running. Today’s expected peak is 24,900 megawatts, the highest in years.


Graph showing the daily increase in peak demand for the week of July 6, 2020


A passing thunderstorm yesterday in Toronto and southwestern Ontario also shows how weather can change demand rapidly. The rain provided a quick reprieve from the heat and humidity, so air conditioners cycled off, contributing to a drop in Ontario's electricity demand.

Graph showing drop in electricity demand becasue of changes in weather

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