Power outages caused by the record-breaking heat wave could continue for the rest of the week, as high electric use and hot conditions strain the Inland Northwest’s power grid.
Heather Rosentrater, Avista's senior vice president of energy delivery, said the utility initially believed its infrastructure could handle the heat and spike in energy use.
“The load was higher than expected, some of our infrastructure wasn’t able to operate as expected, and it came more quickly than expected.”
She said the utility is now working to decrease the number of people who will lose power for the remainder of the heat wave, but many are still vulnerable because of the strain on the grid.
“That’s the biggest load variability we have based on a normal temperature day and a really peak day. Normally, the air conditioner kicks on, and it kicks off. We get some diversity at that peak by cycling at different times for different customers. But when everyone has their air conditioning on all the time, that’s what causes these unprecedented peaks on our system.”
She said Seattle has not seen as many power outages because only around a third of the city has air conditioning.
The outages over the next week will likely be constrained to the city of Spokane, and some people may experience them multiple times. They are scheduled to only last an hour each.
Rosentrater said the blackouts are caused by two issues: the heat decreases the electric load their infrastructure can handle, and air conditioning use has skyrocketed
She said the neighborhoods experiencing blackouts are where those issues are most severe.
“When you have distribution constraints, they’re unfortunately there where they are in the system. You can’t change where the outages are occurring to help those constraints, they’re in certain geographic areas based on the equipment that is constrained, that’s why we haven’t been able to spread where those outages are occurring across different customers.”
Rosentrater said all customers should make sure their contact information is up to date so that Avista can contact them on a timely basis. She says they should also look for ways to reduce their power usage. Methods Avista has suggested include not using the oven, dishwasher and drier, which all generate heat and are high electricity users, and setting the air conditioning on as high a temperature as comfortable, such as 75 instead of 72.