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Heat wave projected to contribute to highest peak demand since 2013

July 5, 2018

Today’s (July 5, 2018) projected peak demand of 23,256 MW at hour ending 17 (EST) could become the highest peak Ontario has experienced since July 17, 2013, when Ontario demand reached 24,927 MW. This week’s heat wave has already presented the top three peak demand hours of 2018 to date. The all-time peak demand for Ontario was set in August 2006 when it reached 27,000 MW.

The heat has driven up demand as Ontarians’ air conditioners run full tilt. Air conditioning accounts for roughly 40% of residential electricity consumers’ use during the summer months.

The IESO takes steps to prepare for situations like these weather events to ensure the grid is reliable and resilient. For example, some transmission and generation outages were deferred to a later date and conversations have been ongoing with neighbouring jurisdictions and local distributors to stay coordinated and prepared for any unexpected system events. The province is expected to have adequate electricity supply through the remainder of the heat wave.

For more information about Ontario peak demand see the Peak Tracker webpage, which features system peak forecasting, real time data for tracking and verified Ontario demand data.


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