Update, 1:35 a.m. Tuesday: The power outage that hit southwest Palo Alto on Monday night appears to be ending. The city Utilities Department just posted an update saying the number of customers without power is down to 36. A few hours ago, 4,462 customers lost their power. Still no word on the cause of the outage.
Original report, 12:01 a.m. Tuesday: The Palo Alto Utilities Department reports that 4,462 customers lost electric power starting at 10:33 p.m. on Monday (Sept. 6). The estimated time of restoration is 8 a.m.
The city hasn’t given a cause for the outage.
As the map shows, the outage is mainly southwest Palo Alto.
This is the sixth power outage in Palo Alto so far this year. Previous ones were on:
• Aug. 22 — 3,400 customers lost power in the northeast part of town;
• Aug. 8 — A bird in a transformer knocked out power to 60 customers in south Palo Alto;
• Aug. 5 — A tree branch fell on a power line, cutting power to 1,700 customers;
• June 14 — A tree branch knocked out power to about 225 customers in the Barron Park area including Matadero Avenue, Margarita Avenue and Roble Ridge;
• Feb. 18 — A mylar balloon floated into a power line and caused a short circuit that resulted in 4,500 customers in southeast Palo Alto losing their power.
For the past five days, state officials had been urging residents to conserve power between 4 and 9 p.m. to avoid rolling blackouts.
High temperatures have led to more use of air conditioners.
Palo Alto’s high on Monday was 98 degrees, breaking the 2008 record of 95.
However, the grid operators didn’t announce any rolling blackouts on Monday. PG&E, which supplies power to Palo Alto’s city-owned utility, was reporting scattered outages in the South Bay due to transformer failures.
PG&E said transformers need time to cool down or they’ll fail, and temperatures haven’t gone down enough at night. PG&E reported isolated outages in Sunnyvale, Campbell, Santa Clara and several neighborhoods in San Jose.
A surge in demand is expected today when people return to work, which boosts electricity demand.
The California Independent System Operator, which runs the state’s power grid, is bracing for energy deficits and said rotating outages are possible Monday.
“We have now entered the most intense phase of this heat wave,” said Elliot Mainzer, chief executive officer of the system. “Forecasted demand for Monday and Tuesday is at all-time record levels and the potential for rotating outages has increased significantly.”
The state is looking at energy deficits of 2,000-4,000 megawatts — up to 10% of normal electricity demand.
“In fact, we need two to three times as much conservation as we’ve been experiencing to keep the power on,” Mainzer said.
During the heat wave over the past five days, consumers have done better than expected, officials said.
Power use over past two evenings came in about 1,000 megawatts below what was expected — about 2% below the state’s forecast for energy use, Mainzer said.
“We know it’s been a long haul, and it’s about to get even more difficult, but the efforts of electricity consumers and our partners at the utilities and state agencies are making a real difference,” Mainzer said.
A statewide Flex Alert is in place for Monday from 4 to 10 p.m., and the ISO also issued the Energy Emergency Alert 1 for 5 to 9 p.m., indicating that energy deficiencies are expected because all resources are in use or committed.
During a Flex Alert, residents are urged to set their thermostats at 78 degrees, not cook anything with an electric oven, don’t use a washer or dryer, and avoid re-charging electric cars until the overnight hours. — From staff and wire reports