With 2.2 million customers spread across 7,600 square miles of service area, isolated power outages occur daily. Most often, these disturbances last just a few seconds, but some may last longer, depending upon the cause. While weather is the most common culprit, events like vehicle accidents or small animals contacting power lines can also cause outages.
Nationwide, weather-related problems (storms, winds, tree damage, high demand for electricity during periods of high temperatures and humidity) are the chief cause of disruptive power outages.
Outage Types: Momentary vs. Sustained
Do you know the difference? Despite the inconvenience, momentary outages actually prevent more serious power problems.
- If your digital clocks are flashing 12:00 or if your lights blink or go out for a few moments, a momentary outage has occurred.
- Momentary outages are often caused by some type of interference on power lines, such as an animal or tree branch coming in contact with the line.
- We place automatic devices on our power lines to protect them in somewhat the same way circuit breakers protect your home's wiring. The devices quickly isolate the problem and perform a function similar to resetting a circuit breaker in your home-safely restoring power to the line within moments.
- While momentary interruptions are inconvenient, in the majority of cases, these automatic devices prevent longer outages.
- Sustained outages are planned or accidental total losses of power in a localized area of the community. These types of outages usually last more than five minutes.
- A sustained outage may be caused by storms, accidents or equipment damage.
- Sometimes it's necessary for us to intentionally interrupt service in order to safely perform equipment repairs and maintenance. If possible, we notify customers in advance of a planned interruption.
- If you use a generator during a sustained outage, please read our tips on Safely Operating Portable Generators.
Based on data supplied by the Edison Electric Institute
What we're doing to minimize outages and ensure reliable service
We work year-round to maintain, repair and improve our electrical system. Our goal is to minimize outages and ensure reliable electric service.
This work includes:
- Trimming trees to avoid interference with power lines and other electrical equipment.
- Inspecting power lines and other electrical equipment, such as transformers, fuses and regulators, and repairing or replacing equipment as needed.
- Inspecting utility poles and replacing them as necessary.
- Adding electrical circuits and substations in rapidly growing areas.
- Monitoring outages to identify areas experiencing frequent outages. We then analyze the outage cause(s) to determine what can be done to correct the situation. This may include scheduling supplemental tree trimming; adding, repairing, replacing or upgrading electrical equipment; or re-routing power lines. Once this additional work has been completed, we continue to monitor outages and growth in the area to develop additional corrective measures as needed.
Please remember, however, that it is not possible to eliminate all power outages, such as those caused by storms or vehicle accidents.