Although customers are not expected to notice any change or interruption of service, Entegrus is notifying customers of a province-wide voltage reduction test planned by the Independent Electricity System Operator (IESO) for Thursday, July 23rd, 2026.
The test will consist of two voltage reductions exercises, each approximately one hour in duration. The first will be a 3% voltage reduction exercise from 09:00 to 10:00. The second will be a 5% reduction exercise from 13:00 to 14:00.
The IESO conducts province-wide system voltage reduction tests every 18 months, the last test took place on January 21st, 2025. These tests are necessary to determine how much power could be reduced in the event of an emergency situation, to identify equipment problems & to keep staff familiar with procedures, and to identify any deficiencies in the procedures that may need correction.
For additional information on voltage reductions, visit the IESO website or contact IESO Customer Relations by sending an email to IESOCustomerRelations@ieso.ca.