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IMO Declares Power Warning as Record Cold Weather Strains System

March 3, 2003

The Independent Electricity Market Operator (IMO) has declared a Power Warning as record cold weather and high electricity demand, combined with short-term generation and transmission system limitations, have put a strain on power supplies.

Consumers and industries are being asked to immediately reduce their electricity consumption. This warning is in effect until 8 p.m. this evening.

Power Warnings are issued by the IMO during periods of high demand for electricity, when supplies of reserve power are low. Any further reduction in transmission or generation availability or any increase in demand could create shortfalls of electricity. If all sources of supply are exhausted, the IMO will take protective actions such as a system voltage reduction, or rotating cuts to supply. In these circumstances, no additional public notice may be possible.

Consumers and businesses can reduce the demands on the electricity system by immediately:

  • Turning off all but essential internal and external lights

  • Lowering the thermostats on furnaces, baseboard heaters and space heaters

  • Limiting use of electrical appliances and space heaters, especially through the peak hours of 4 p.m. to 8 p.m.

The Independent Electricity Market Operator (IMO) is responsible for operating and regulating Ontario's wholesale electricity system and the wholesale electricity marketplace -- linking buyers and sellers while directing the flow of electricity on Ontario's transmission system from generators and suppliers to local distribution companies and wholesale buyers.

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