The Oregon Public Utility Commission heard details of power generation impacts from back-to-back February winter storms, which were called the worst in 40 years in the Pacific Northwest, as utilities gave testimony March 30 during a special meeting.
No action was taken as the meeting was not part of an official docket. Rather, it was the first step on any future action on this issue, OPUC executive director Mike Grant said.
"The ice storms this February were historic and left hundreds of thousands of customers in the Willamette Valley without power for a period of time," Grant said.
Wind speeds in Salem, Oregon, reached 41 mph in February, according to the US National Weather Service. Salem's strongest sustained wind was 58 mph in October 1962 during the Columbus Day Storm, the last time the region experienced such a strong wind event, utility and commission representatives said.
"We see some sort of extreme weather set of events that are emerging," Commissioner Letha Tawney said.
The governor declared a state of emergency due to the severity of the winter storms, which lasted for two weeks in some areas. A trifecta of snow, ice and wind led to critical transportation failures and loss of power and communications capabilities.
The extreme temperatures and increased heating demand caused power prices to spike to 23-month highs as John Day on-peak day-ahead reached to $113.50/MWh Feb. 16, NOB on-peak day-ahead hit $175/MWh Feb. 17 and COB on-peak day-ahead climbed to $109/MWh Feb. 18, according to S&P Global Platts pricing data.
PGE impact
"These caused extensive widespread damage," Portland Gas and Electric President and CEO Maria Pope said about the impact to power capabilities.
The storms, which began Feb. 11, were the worst seen in the region in 40 years, Pope said.
"This set of storms exposed areas where we need to do better," Pope said.
The February storms were of a magnitude not seen since the Columbus Day Storm, said Allen Bekkedahl, PGE vice president of grid architecture, adding every inch of ice around a power conductor a foot long equated to 3 pounds of weight, which comes to 3,000 pounds of additional weight where lines meet.
While PGE customer outages reached 325,000 at the peak, a total of 420,000 customers were without power during the course of the back-to-back storms, Pope said.
"Many customers experienced multiple outages," Pope said, adding that the utility restored power in 750,000 customer outages during the storms, but did not have any generation outages at power plants, unlike the situation in Texas during the same time.
PGE and PacifiCorp
PGE had 70% of its system impacted by this storm, Bekkedahl said.
In comparison, 10% of PacifiCorp's customers were impacted, Allen Berreth, PacifiCorp vice president of transmission and distribution operations.
At its peak, 80,000 customers had impacts, with 85% of customers restored within five days, Berreth said.
Discussing equipment damages, Berreth said the utility replaced 251 poles, 180 transformers and 165,000 feet of conductor.
One of the biggest challenges was that different areas saw different equipment affected, so PacifiCorp is looking into how to use that information, Berreth said.
"Every situation creates an opportunity for learning, and this event was no different," Berreth said.
