In the Pacific Northwest, winter brings rain, windstorms and power outages. That means when it’s darker and colder we’re more likely to lose our lights and heat.

Now, local utilities are bringing in automated which keeps fewer homes from going dark.

It’s called Distribution Automation or DA. It’s also known as self-healing power lines. That means instead of an entire circuit, for example, about 3,500 homes and businesses going out, only 500 of those customers would go out.

The system would reroute the power on its own.

Smart circuit breakers are attached to power poles, often identifiable by a glass cap at the end which looks like a jar with a round red indicator marked with a letter “C,” when everything is up and running. Each power pole is equipped with computerized boxes mounted well out of reach.

“The idea is these are smart, so they’ll talk to one another,” says Bruce Lee, who works the lines for Seattle City Light and walked us through how the system works. It’s that talking between towers on that circuit that makes the difference, says Lee. “Within milliseconds (they) devise a switching scheme and they’ll do the switching on their own.”

Seattle City Light has five circuits set up in the north and south ends of its service area. Several locations are in Lake Forest Park and shoreline, communities with plenty of trees. Another half dozen are planned targeting areas at the most risk for outages.

Puget Sound Energy, the state’s largest utility has one self-healing circuit project up and running in Whatcom County and five other self-healing projects tested and ready to online in November of 2017 in Kenmore, Juanita, Woodinville, Issaquah, Maple Valley, Mt. Vernon and on the Microsoft campus. By the end of the year, PSE promises an additional five projects in Kent, Federal Way, Oak Harbor, Tumwater and Olympia.
Do they work?

Seattle City Light says of their five circuits went online in 2016 and operated over last winter, “…about 13,300 fewer customers suffered interruptions compared to estimated outcomes without DA,” according to a utility report.

PSE says the Whatcom County installation has had one save.

Snohomish County PUD is also looking seriously at installing these self-healing systems, says a utility spokesman.