Skip Links
Sector Participants > IESO News > IESO to Conduct Routine Voltage Reduction Test on January 19

News and Updates

IESO to Conduct Routine Voltage Reduction Test on January 19

January 7, 2021

A routine voltage reduction test will be conducted on Tuesday, January 19, 2021, as part of mandatory testing of the IESO’s emergency operating measures. The test is an important tool for ensuring the reliability of Ontario's electricity grid.

Voltage reductions lower demand quickly and minimize the likelihood of service interruptions, helping the IESO maintain the reliability of Ontario’s power system during a variety of unplanned occurrences.

A three per cent reduction is expected to occur from 9 a.m. to 10 a.m. EST. A five per cent reduction is planned for 1 p.m. to 2 p.m. EST. These tests are normally conducted every 18 months.

Voltage reduction tests have three key purposes:

  • To determine how much power can be reduced through the two levels of reduction.
  • To identify equipment problems so they can be addressed.
  • To help keep IESO and market participant staff familiar with procedures to execute voltage reductions and identify any deficiencies in the procedures that may need correction.

Consumers with questions about the test should contact their local distribution company. A list of local distribution companies is available.

More information about voltage reductions is available on the IESO website or by contacting IESO Customer Relations at 1-888-448-7777.

< Back to IESO News