Understanding and preventing | Power outages

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When the electricity goes off, what’s the reason?

There are three main reasons for your loss of power: a power outage; a planned service interruption for grid maintenance purposes; or an interruption requested by the emergency services.

When the electricity goes off without warning, that’s an outage. Precipitation, strong winds or even overly curious animals are among their many possible causes. Each outage is unique, but whatever the circumstances, rest assured that our teams will work round the clock to get your power up and running in the shortest possible time.

Then there’s maintenance work. Keeping the power system reliable and in good running order calls for regular maintenance—and to perform the work safely, we sometimes need to cut the power supply. We call this a planned service interruption. Don’t worry, these interruptions always feature on the map of scheduled interruptions and any affected customers are informed well in advance. That’s why it’s important to keep your phone number and email address up to date in your Customer Space.

Lastly, Hydro-Québec might sometimes be asked to cut the power in a given area by emergency responders like the fire department or the police. This is what we call an emergency interruption. Whatever the incident—fire, gas leak, flooding or something else—our priority is public safety. It’s important to remember that, in these situations, it’s not the grid that’s at fault. In other words, we’re still able to provide electricity service, but are required to interrupt it for reasons beyond our control. It’s also hard to predict when the service will be restored, since we have to wait for the emergency services to declare the situation safe and authorize us to turn the power back on.

Vidéo : Understanding what causes power outages

Duration : 1 minute 32 seconds

Transcription de la vidéo Understanding what causes power outages

Understanding power restoration priorities and steps

Power failures are never pleasant. Rest assured that when an outage occurs, Hydro-Québec’s crews make every effort to restore service as soon as possible to the greatest number of customers. The service restoration strategy will depend on the type and scope of outage. The order of priority can vary depending on the situation, the specific needs of a municipality or the requirement of public security officials.

Learn about the various steps in restoring service and why the time it takes to restore service once an outage has been detected can differ quite a bit. Whether big or small, each outage has its own unique characteristics.

Step 1 – We restore service remotely whenever possible
If an incident trips a system breaker—a device that functions a bit like the circuit breakers in your home—we first try to restore power supply on the lines using remote operations.
Step 2 – We go on site to determine the cause
If the problem persists, a line worker goes on site to inspect the system and determine the cause of the outage. This step can be time-consuming, especially if the weather is bad or if the premises are difficult to access.
Step 3 – Evaluation and solution
Once the cause of the problem has been identified, we assess the extent of the damage on site and determine what work needs to be done to repair the damage and restore service.
Step 4 – Crew scheduling
We then assign the teams required to do the job. Whether it involves cutting branches or replacing damaged equipment, our crews always do their utmost to restore service as soon as possible.
If a major weather event occurs
In the event of extreme weather conditions that cause several outages, estimated restoration times vary as the extent of the damage—and the work required to repair it—is determined.