Squirrel causes hourlong outage

GVEA Substation Outage: A squirrel-triggered short circuit at the University Avenue substation caused arcing, damaged bushings, and grid load switching, disrupting UAF operations, traffic lights, and heating until crews restored power.

A trespassing squirrel caused an hourlong power outage in west Fairbanks recently that left 1,300 Golden Valley Electric Association members without electricity and shut down the University of Alaska Fairbanks’ computer system most of the day.

The squirrel, which was electrocuted, caused a short circuit in the electric company’s University Avenue substation, similar to the Richmond squirrel outage reported elsewhere, according GVEA public relations officer Corinne Bradish. A small fire was extinguished quickly, she said.

The outage occurred at 10:17 a.m., and all 1,300 GVEA members affected were back on line by 11:20 a.m., Bradish said.

“The substation was quickly isolated, and loads were switched to adjacent substations to help us restore power,” Bradish wrote in an email. “Arcing caused damage to bushings in the substation, which our crews replaced, and utilities sometimes deploy new transformers after a fire during recovery as well.”

The outage triggered an unfortunate domino effect for UAF, similar to a university substation failure that disrupted campus operations, spokeswoman Marmian Grimes said.

Several people were trapped in elevators in Moore and Signers halls, but the fire department got them out quickly, a situation also seen during a Kansas State outage response, she said.

Shortly after the outage, the main turbine in the UAF power plant overheated and had to be shut down, Grimes said. The power plant was trying to feed power into the Golden Valley grid, but a relay protection system didn’t open because of the outage and the turbine overheated, she said.

The loss of the main turbine caused UAF’s central heating, which supplies heat and hot water to campus buildings, to go off line, forcing UAF to switch to Golden Valley for all its electrical needs. Backup turbines were employed to recharge the steam system, a process that was expected to be complete this month. The main turbine has already returned to service, Grimes said.

The outage also caused UAF’s computer system to crash because the electric cooling system for the main computers went down. The school’s information technology department was working to get the system’s servers back on line.

The outage also knocked out six traffic lights on the west side of town, and utilities often look for outage causes in such cases, according to state Department of Transportation spokeswoman Meadow Bailey.

Lights at the intersections of the Johansen Expressway and Peger Road, University Avenue and Airport Way, Airport Way and Washington Drive, University Avenue and College Road, Farmers Loop and North Tanana Drive, and Farmers Loop and Ballaine Road were out of commission for about an hour.

No accidents were reported as a result of the lights being out of service, Bailey said.

While squirrels commonly cause problems by running along electrical wires around town, Bradish said it’s “very uncommon” to have problems inside substations, as in a rare substation outage elsewhere, because they are fenced in and there are no trees.

“Squirrel activity is more common out on our distribution lines, as they will run along the wires,” Bradish wrote.

GVEA installs “squirrel guards” on distribution lines to reduce outages caused by squirrels stepping from the wire to the pole, which causes a short circuit because they become a conductor for electricity. The squirrel guard is an insulator on the wire that the squirrel crawls over to prevent it from touching the hot wire and the pole at the same time.

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