California state legislators held a hearing in San Diego on Wednesday looking into the September 8th blackout that affected seven million people in southern California, Arizona and northern Mexico.
At the hearing, grid operators and regulators said they still don’t know what caused the blackout, but that it wasn’t the fault of a single utility worker in Arizona, as was originally reported.
Regulators say that worker did trip a key power line from Arizona to California. But there were at least 19 other problems along the grid that led to the blackout. Those included one power plant in Mexico that went offline and three in the Imperial Valley.
Still, many of the those questioned at the hearing said the blackout never should have occurred.
“We carry reserves for such contingencies, and we constantly monitor the system, measuring the system every four seconds,” said Stephen Berberich, president and CEO of the California Independent System Operator, which coordinates most of the state’s grid.
The power industry officials said it could take anywhere from two months to one year to find out why the outage became as big as it did.
The Western Electrical Coordinating Council assists various power system operators with the flow of electricity across 14 states, two provinces in Canada and part of Baja California Norte, according to Maher. Cal-ISO does the same within the state.
San Diego Gas & Electric President and CEO Michael Niggli credited customers for the return of power within 12 hours instead of two days, as originally estimated.
Niggli said unplugging air conditioners and other energy-hogging electronics allowed them to restart their system faster than expected.
