Authorities are still looking for reasons why a failure at one generator triggered the need for a controlled power outage that left 115,000 customers without power Sunday afternoon.
The emergency started at 11:53 a.m. when a generator in San Diego County went off line. Workers at the California Independent Systems Operator began scrambling to re-route power. By 1 p.m., it was clear that they weren’t going to be able to compensate for the disruption.
“When that was not being effective we had to make the immediate decision, along with our reliability coordinator, to reduce the load on the system,” said Steven Greenlee with Cal ISO.
That’s when San Diego Gas & Electric got the call to reduce demand by 150 mega-watts, which translated into roughly 115,000 customers throughout their system. They quickly began a series of controlled outages spread throughout their territory. The lights went out at homes, restaurants and stores throughout the area.
“So we implemented this order as quickly as we could. And there wasn’t time to notify customers or anything like that,” said Hanan Eisenman with SDG&E.
Police were left scrambling to locate and cover intersections left without power. Customers were left to monitor the utilities’ Twitter account until the power came on after 3 p.m.
California ISO controls 80 percent of the power in California. Officials are still looking into why the loss of one of the 850 generators led to this level of disruption.
