On the foggy morning of Feb. 17, 2010, Palo Alto plunged into darkness at the beginning of the morning commute. All 28,000 customers lost power for 10 hours. Computer systems were down, traffic snarled at intersections after stoplights went out, Stanford University Hospital and Lucile Packard Children's Hospital operated on emergency power, and most city facilities, including City Hall and the Police Department, lost electricity, although police had limited power through a generator, the city reported that day. No one dared to estimate the losses to local businesses.
Palo Alto's "Day the Earth Stood Still" was caused by a private plane that crashed into a city's utility tower near the Palo Alto Municipal Airport -- taking out all three of the city's power conduits -- and landed in a fiery blaze in an East Palo Alto neighborhood.
It was a wake-up call.
But five years after the twin-engine Cessna 310R accident killed pilot Douglas Bourn and two fellow Tesla Motors employees, Andrew Ingram and Brian Finn, little has changed. Palo Alto officials are still looking at alternative power supplies to prevent another disastrous blackout.
Negotiating for additional electrical transmission lines and building the infrastructure for them could be years down the line, a city Utilities Department spokesperson said this week.
All of Palo Alto's electrical power comes from three power lines located east of U.S. Highway 101. All three were impacted by the crash or by the debris it generated.
The incident was later blamed on Bourn's failure to follow departure instructions by banking left over the East Palo Alto neighborhood instead of right over the San Francisco Bay and his failure to attain sufficient altitude to avoid striking power lines, according to a National Transportation Safety Board report.
Palo Alto was looking at alternative power supplies and their costs for years prior to the crash, Tomm Marshall, assistant director of the city's Utilities Department, said at the time. Two studies found that adding a transformer at the Stanford Linear Accelerator Center could cost about $45 million and require permission from the U.S. Department of Energy (DOE), which would operate the new transformer. But the DOE has not been supportive of the plan.
The city also considered converting its 115kV lines to 230kV lines, which would save the city about $1 million annually. The new lines would be installed underground, safeguarding it from aircraft and other hazards, Marshall said. Cost for that project was estimated at $200 million.
But neither idea has gone anywhere so far.
Utilities spokeswoman Catherine Elvert this week said the city has since been involved in regional transmission-planning efforts conducted by the California Independent System Operator (CAISO) to develop an alternative transmission system.
"Our participation in the annual process has resulted in two alternatives to diversify transmission routes to the city that are currently under consideration. The first alternative under consideration would entail PG&E building a new transmission access point extending from the city's receiving station to a PG&E site at NASA Ames in Mountain View. The second alternative under consideration would involve constructing a new transmission line from a city site near Sand Hill Road to a site near the Department of Energy's Stanford Linear Accelerator (SLAC)," she wrote in an email.
Both alternatives are considered viable solutions to problems related to the airport, she said. But the second alternative, a transmission line to SLAC, still involves several groups that need to negotiate impacts and costs. The preferred alternative will be contingent upon its feasibility and cost, she added.
"Currently, we expect that a final decision on the alternatives will be made by the end of 2015.
Construction may take from three to five years after a decision is made. A project of this size will require an environmental-review process, followed by engineering design, manufacture of specialized equipment and then construction," she said.
Upgrading the system is taking a long time due to its many moving parts, she said.
"There are many entities involved. It really is a very important issue to the community. We want to make sure we fully arrive at a decision that is best for the community," she said.
Palo Alto has put in backup generators to improve reliability and redundancy in the system. The city has made improvements to keep essential water services going in a power emergency, Elvert said. The city maintains a fleet of generators to provide electricity to pumps servicing city water wells and reservoirs. Two new generators have been sited at reservoirs to provide power during electric outages.
The city has also upgraded large parts of its lines from 4kV to 12kV, which is "pretty major" and is an ongoing process that improves reliability, she said.