A second blackout plunged parts of Idaho into darkness on Wednesday as officials focused on a Wyoming power plant and its transmission lines as the possible source for the outage.
A short-circuit along the same transmission lines may have triggered the rapid chain-reaction outages that knocked out lights and telephone service for 1.5 million to 2 million customers in eight Western states on Tuesday.
After Wednesday’s disturbance, utility officials could not re-energize the power lines from the Jim Bridger coal-fired plant near Rock Springs, Wyo., and a substation in southeastern Idaho, said Gary Donnelly, a spokesman for PacifiCorp, co-owner of the plant with Idaho Power Co.
The utilities sent up a helicopter to inspect the 200-mile stretch of power line, Donnelly said.
Wednesday’s disruption apparently was limited to Idaho. Power flickered out in southern Idaho at 2:10 p.m. MDT, and the Idaho Statehouse was among the buildings that lost power for a few minutes.
“We have manually overridden the system and we are manually beginning to recover the system,” Dennis Lopez, a spokesman for Idaho Power Co., said late Wednesday afternoon.
Utility officials said it could take a week to find out just what caused Tuesday’s short-circuit, which sent disturbances rippling through the Western power grid.
“We can rule out sabotage. We can rule out UFOs. I think we can rule out computer hackers,” said Perry Gruber, spokesman for the Bonneville Power Administration in Portland, which operates a series of Northwest hydroelectric plants.