For the Palo Alto Utilities, an organization that prides itself on reliability, March 27 marked the beginning of a brutal and humbling half-month stretch.
That was when a maintenance project went awry at the Park Boulevard substation, cutting off power just before 5 p.m. for about 7,000 customers, who were without service for about two hours. The power failure was accompanied by a communication breakdown, as the city struggled to get the word out, the Utilities Department's outage map malfunctioned and hundreds of customers who called to report the outage were greeted with automatic messages, placed into queues or hung up on.
Even days later, customers and members of the media struggled to understand what caused the outage. City Manager Ed Shikada and utilities staff repeatedly referred to a "preventive maintenance project" that went wrong at the substation without defining what that means.
Ultimately, it was determined that the March 27 outage occurred when the circuit breakers were replaced at an aging substation. The project involved changing settings on substation relays — devices in power systems that disconnect an element from the system from service when it suffers a short circuit or starts to operate abnormally, according to Catherine Elvert, communications manager at the Utilities Department. Relays, she said, are designed to prevent shorts or abnormal operations from interfering with the rest of the system.
After the relays were put back into service at the substation, they initiated a circuit breaker to trip, causing the power outage.
"These are abnormal operating conditions at a substation and not an occurrence that customers should anticipate will happen on a regular or frequent basis," Elvert said in an email. "It was an unusual situation which hopefully should not occur again."
Even despite the wide scope of the outage and the communication struggles, the March 27 outage probably wouldn't have stood out if it hadn't been followed by another power outage on April 4, when a failed underground transformer knocked out power to about 570 customers around 9 p.m. According to Utilities Director Dean Batchelor, the city was able to restore electricity to 445 customers that night; the rest didn't get their power back until 4:30 a.m.
On April 9, Batchelor provided an update about the two outages to the city's Utilities Advisory Commission.
"Our goal is to provide reliable service and we didn't do a very good job over the last two weeks with that," Batchelor said. "We understand that from the utility's perspective, reliability and safety is high on our list."
Four days later, on the evening of April 13, about 2,000 customers in the Old Palo Alto and Ventura neighborhoods lost power for about three hours, an outage that the Utilities Department attributed to a failed underground cable.
For a city that often touts the reliability of its municipal utilities and that is banking on electrification of cars and buildings to achieve its aggressive emission-reduction goals, the spate of outages has offered both a reality check and an opportunity for self-reflection and troubleshooting. In an April 16 post on the city's Medium page, Batchelor detailed the city's plan to address the problems that the recent outages had exposed.
The plan includes conducting a third-party review of existing systems and procedures; an evaluation of the electrical system to identify any unexpected issues; and hiring additional system operators.
Batchelor also noted that the city is working to address the limitations of the call system, including adding more capacity to receive calls and ensuring that calls won't get dropped.
"We are also working on ways to share and confirm an initial outage, in the hope of reducing customer calls into the Utilities phone system," Batchelor wrote.
According to the Utilities Department, the city averages about 25 outages a year, with recent causes including downed tree branches, floating mylar balloons and, in one recent case, a goose that flew into a power line. The most significant outage in recent years occurred on Feb. 17, 2010, when a small plane attempting a liftoff at Palo Alto Airport hit high-power lines and crashed. All three plane passengers died in the accident and all 28,000 utility customers lost power for more than 10 hours as the plane damaged all three transmission lines that the city relies on to connect to the power grid.
Since then, utility officials have explored adding an additional transmission line. City staff had spent years negotiating with Stanford University and SLAC National Accelerator Laboratory but could not reach an agreement on interconnection. In February, utilities staff reported that with the option exhausted, it is looking to explore an interconnection between the city's electric substation at Adobe Creek and PG&E's Ames substation.
"Although this connection is at the same transmission voltage level as the City’s existing interconnection, and therefore does not offer a reduction in electric transmission costs, it does significantly increase reliability and resiliency," the report states.
Reliable electricity is key to the council's goal of reducing carbon emissions by 80% by 2030, with 1990 as the baseline. According to a new study conducted by Utilities and Public Works staff, as well as the consulting firm Aecom, reaching the goal would require a wholesale conversion of gas appliances to electrical ones in the city's single-family homes as well as widespread adoption of electric vehicles.
At the April 9 meeting of the Utilities Advisory Commission, David Coale, a member of the group Carbon Free Palo Alto, urged city staff and commissioners to reconsider their effort to pursue an interconnection and to instead spend their time and resources on local resiliency, which the city hasn't quite mastered.
"If we're going to do electrification, the utility needs to go a lot further in making the system more robust to make our residents believe that electrification is going to be a good idea," Coale said.
Frank Flynn, who lives on Matadero Avenue, alluded to the March 27 outage in a recent letter to the council, noting that the electric utility "appears to be the least reliable utility we have." In the 30 years that he has lived in his home, Flynn wrote in the April 7 letter, he does not recall ever seeing his gas service go off.
"If we do want the user to switch to electric service then our electric service has to be better," Flynn wrote. "Otherwise residents will simply buy portable generators and such that are significantly worse for pollution.
"There is no (good) reason that our electrical service cannot be more reliable but it will never become more reliable unless we measure it, analyze each and every failure, and commit to fixing every issue," Flynn wrote.