Service reliability is measured by the system average interruption duration index (SAIDI), which reflects the average service interruption time per customer. Service interruptions can be caused by scheduled system maintenance, bad weather, invasive vegetation or defective equipment. Rollout of next-generation meters has improved outage detection and service restoration.

We are investing heavily in upgrades to equipment and various facilities to make the system stronger. According to the standards developed by the North American Electric Reliability Corporation, a vegetation control program must also be implemented to prevent outages and accidents.

All kinds of emergencies can occur, from equipment breakdown to natural disasters. Emergency measures are managed as an integral part of Hydro-Québec’s procedures.

We have signed a mutual support agreement with neighbouring systems. Under this agreement, we cooperate with other North American power utilities when natural disasters occur.

The system average interruption duration index (SAIDI) measures the average annual service interruption time per customer. The overall SAIDI is obtained by adding the normalized distribution system index to the unadjusted transmission system index. The normalized distribution system SAIDI excludes interruptions that are mainly caused by extreme weather conditions. The SAIDI is based on an international standard set out by the Institute of Electrical and Electronics Engineers (IEEE). The increase to the transmission system index in 2016 was largely due to a major power outage that followed flooding to the Notre-Dame substation in east Montréal, which supplies 115,000 customers. This incident alone represented 7.3 minutes of interruption.
Even in extremely cold weather, system reliability and service quality are maintained.

Activities in 2016

  • Service hours were extended from 8 a.m. to 8:30 p.m. on weekdays and from 9 a.m. to 5 p.m. on weekends.
  • Marking a first, customer relations centres were open on July 1 from 9 a.m. to 5 p.m. This holiday is traditionally moving day in Québec. On that day, representatives responded to 3,758 calls.
  • For 90% of simple service connections, service was provided within 10 working days (83% in 2015). We completed 15,753 simple service connection requests.