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DEMAND OVERVIEW

Electricity Demand Records

The winter peak for electricity demand set on December 20, 2004 was 24,979 MW.
The summer peak for electricity demand set on August 1, 2006 was 27,005 MW.

Forecasting Peak Electricity Demand

Electricity supply and demand must be in balance every minute of the day. The IESO must forecast peak demand to ensure that generation will be available to meet the peak.

Peak Demand Forecasts

Season Seasonal Normal
Weather Peak (MW)
Extreme Weather
Peak (MW)
Summer 2008 25,493 27,748
Winter 2008-09 24,335 25,400
Summer 2008 26,684 27,939

18-Month Outlook, March 12, 2008

Demand Patterns Throughout the Day

Electricity demand is primarily influenced by weather, hours of daylight, business hours, school holidays and consumption patterns as people arrive home from work. Typically, demand peaks between 4 p.m. and 7 p.m. everyday. Demand in the middle of the night can be as low as 12,000 - 13,000 MW and can rise by as much as 10,000 MW later the same day.

Total Annual Ontario Energy Demand

Year Total (TWh) Increase Over
Previous Year
2007 152 0.7%
2006 151 -3.8%
2005 157 2.3%
2004 153 1.1%
2003 152 -0.7%
2002 153 4.1%
2001 147 0%
2000 147 2.1%
1999 144 2.9%
1998 140 1.4%
1997 138  

 

RELATED INFORMATION

Average Electricity Demand in Selected Ontario Communities

Toronto:  3500 MW
Ottawa:1000 MW
Hamilton:700 MW
Brampton:400 MW
Guelph:200 MW
Thunder Bay:125 MW
Kingston:100 MW
Stratford:45 MW
Orillia:37 MW
Kenora:15 MW

Where to Find More Information About Ontario Demand

  • Up-to-date demand information is available on the Demand and Price page.
  • The Monthly Market Update provides demand information for the past month.
  • Detailed daily, weekly and monthly market summaries are available on the Market Summaries page of the "Inside the Market" section.
  • The seasonal Power Outlook provides a summary of demand forecasts and generation availability over the next three months.
  • More detailed 18-Month and Ontario Reliability Outlooks are available on the Forecasts page in the "Inside the Market" section.