July 7, 2010

IESO schedules two voltage reduction tests for July 15

VAUGHAN, ON ~ Although not expected to negatively impact electricity consumers in its service territory, PowerStream is notifying customers of province-wide voltage reduction tests planned by the Independent Electricity System Operator (IESO) for Thursday, July 15, 2010.

There will be two tests conducted on that day, a three percent voltage reduction between 10:00 a.m. and 11:00 a.m. DST, followed by a five percent reduction between 2:00 p.m. and 3:00 p.m. DST. Each test will be approximately one hour in duration.

PowerStream along with all other local electricity distribution companies in the province are subject to and must participate in voltage reductions tests, conducted by the IESO every 18 months. The purpose of the tests is to provide the IESO with an opportunity to assess their emergency procedures, ensure staff familiarity and to identify deficiencies. Voltage reductions are implemented as emergency control actions to manage grid reliability under conditions of high demand combined with limited supply.

"The vast majority of consumers do not notice voltage reductions as they are usually within industry standards specified for electrical equipment used by residential and commercial customers,” explained Brian Bentz, PowerStream’s President and Chief Executive Officer. "However, some sensitive equipment during a voltage reduction could be affected depending on the consumer equipment configuration."

PowerStream’s key account customers will be notified of the voltage reduction tests directly though their account representative.

Additional information on voltage reductions is available on the IESO at www.ieso.ca/voltagereduction or by contacting IESO customer relations at 1-888-448-7777.

About PowerStream Inc.
PowerStream is the second largest municipally-owned electricity distribution company in Ontario, providing service to more than 320,000 customers residing or owning a business in communities located immediately north of Toronto and in Central Ontario. The communities served include Alliston, Aurora, Barrie, Beeton, Bradford West Gwillimbury, Markham, Penetanguishene, Richmond Hill, Thornton, Tottenham and Vaughan. PowerStream is an incorporated entity, jointly owned by the City of Barrie, the City of Vaughan and the Town of Markham.

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Media Contact
Eric Fagen
Director, Corporate Communications
PowerStream Inc.
Office Phone: 905-532-4522
Media Line (24/7): 905-532-4400
Email: eric.fagen@powerstream.ca