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Alectra advising customers of voltage reduction tests for March 6

HAMILTON, ON, February 22, 2018 — Although not expected to negatively impact electricity consumers in its service territory, Alectra Utilities is notifying customers of province-wide voltage reduction tests planned by the Independent Electricity System Operator (IESO) for Tuesday, March 6, 2018.

There will be two tests conducted on that day, a three per cent voltage reduction starting at 9:00 a.m. (EST), followed by a five per cent reduction starting at 1:00 p.m. (EST). Each test will last approximately one hour.

Alectra Utilities, along with all other electricity distribution companies in the province, are subject to voltage reduction tests, which are conducted by the IESO once every 18 months. The IESO runs these tests to assess emergency procedures, ensure staff familiarity and to identify any deficiencies.

Voltage reductions are implemented as emergency control actions to manage grid reliability under conditions of high demand combined with limited supply. Alectra Utilities is working to notify key account customers of the voltage reduction tests directly through their account representative.

During voltage reductions, voltages are still within established industry standards for electrical equipment used by residential, commercial and industrial consumers, so there is minimal or no noticeable impact on the general public. Testing gives consumers the opportunity to identify and address equipment problems caused by voltage reduction prior to an unplanned event.

For additional information on voltage reductions, please visit the IESO website or contact the IESO Customer Relations at 1-888-448-7777.

Should unforeseen circumstances require the voltage reduction tests to be postponed, the alternate date is Thursday, March 8, 2018 at the same times.


  • Voltage reductions have been performed in the past as part of the IESO’s routine testing protocols and, under extreme circumstances, to prevent blackouts. The last voltage reduction tests scheduled by the IESO were held on August 9, 2016.
  • Depending on the demand on the system at the time, province-wide implementation of a five per cent voltage reduction can reduce demand for electricity in the province by as much as 500 megawatts (MW).
  • If there had been an actual voltage reduction event that delivered similar information to a planned test, the normally scheduled test could be postponed or cancelled.

About Alectra’s Family of Companies

Alectra’s family of energy companies distributes electricity to nearly one million customers in Ontario’s Greater Golden Horseshoe Area and provides innovative energy solutions to these and thousands more across Ontario. The Alectra family of companies includes Alectra Inc. (Mississauga), Alectra Utilities Corporation (Hamilton) and Alectra Energy Solutions (Vaughan).

Media Contact:

Rachel Bertone, Media Spokesperson
rachel.bertone@alectrautilities.com | Telephone: 647-339-3826 | 24/7 Media Line: 1-833-MEDIALN

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