From Scott Carlberg

When do outages happen? Answer: All the time, but for various reasons.

Over the past several months, Carolinians have heard a lot about power outages because of hurricanes. That’s because there can be a significant number of outages when violent weather happens. Usually lightning, high winds, and ice are the causes.

Outages may be unpredictable. Have flashlights and batteries ready

What about outages other than in bad weather? To paraphrase a popular saying, “Outages happen.” Here’s why.

Vehicle accidents or sometimes construction equipment can break utility poles, down power lines or cause other equipment damage. Depending on what got damaged a large number of customers can be affected. In this category we will also include someone excavating and hitting a power line which could be underground. For homeowners, calling 811 is a way to check on where utility lines may be buried. (For the record, we even heard of a 2014 outage caused by a crop dusting plane. Well outside the Carolinas, FYI.)

Power lines and a Right of Way

Trees cause outages when they interfere with power lines. Utilities have expert tree trimmers who can scope out potential problems and get to trees before they cause a problem in their right-of-way. Typically, companies work on a multi-year cycle to scan trees near utility lines.  (Some trees that cause problems are outside the utilities’ right of way.)

Wildlife can cause outages, often birds, squirrels or snakes looking for a hideout are the issue. “Many of these creatures are attracted to the humming warmth of electrical equipment, while snakes slither into substations looking for food, often bird’s nests,” says a Duke Energy Illumination story. Companies put in barriers to small animals, but that can’t stop all of them.

Equipment that is aging can sometimes give-out. Like all utensils we have in our lives – phones, microwaves, cars – they only last so long. Predicting a failure is tough.

Sometimes customers see a brief blink in power, a momentary outage. That is a sign that a safety mechanism is working for the customer. If a tree, for instance, briefly comes in contact with a line, there may be a short circuit. Then a breaker interrupts the power as the system tries to clear the problem. It may happen a couple times. One power company says that almost a third of short circuits take care of themselves. If the problem continues, the power company goes to the next stage of repair.

Part of an outage map from Duke website. Helpful information; easy to find. (10/21/18)

There are outage maps available to the public:

In 2017 there were almost 37 million people affected by more than 3,500 reported outages (source). As a nation, electric customers experienced an average of 1.3 interruptions and went without power for four hours during the year. (EIA) Averages are deceiving, though, as when some states (maybe like the Carolinas?) are hit by two hurricanes in a month. That is a challenge.