As Silicon Valley Grows, PG&E Adds Electric Capacity While Improving Reliability

By David Kligman


PG&E project manager Peter Hypnar assesses a newly renovated substation that will improve electric reliability for 50,000 customers. (Photos by David Kligman.)

CAMPBELL — Santa Clara County was a very different area more than 50 years ago when PG&E built its El Patio substation.

In 1960, San Jose had a population of 204,000. Today it’s the third largest California city with nearly 1 million residents. And from 2012 to 2013, Santa Clara County was the fastest-growing county in California.

Naturally, the need for electric reliability has grown as the area has increased in population and become the epicenter for high-tech Silicon Valley businesses.

This week, PG&E will complete $22 million in upgrades to the El Patio substation, which was nearly at capacity when the project began three years ago.

The substation provides power to western San Jose and portions of Saratoga, Campbell and Cupertino — some 50,000 customers in Santa Clara County. Major businesses that rely on the substation for power include San Jose City College, Santa Clara Valley Medical Center and Valley Fair Mall.

Power would continue during repairs

What the upgrade means to those customers is that if one of the transformers were to fail, customers would continue to receive power during the repairs.

“The load was pretty tight with the growth in the area so if we were to lose one of the transformers a lot of people would have lost power,” project manager Peter Hypnar said. “That was unacceptable.”


Apprentice electrician Rick Slusher cleans up equipment last week as a project to renovate the El Patio substation winds down.

The substation is one of the 19 areas where PG&E focused its Cornerstone Project, a multimillion-dollar investment authorized by the California Public Utilities Commission to improve electric distribution system reliability. That project is one of the reasons PG&E’s electric reliability was at an all-time high in 2013.

The substation, located a half mile away from eBay’s headquarters, brings in power at 115 KV, transforms it to 12 KV and then sends that electricity back to the community to power homes and businesses. The concern was that a disruption to one of the three transformer banks could impact reliability to customers, so an 18-foot-tall, 92-ton transformer bank was added to supplement the three existing transformers.

Sectionalized breakers were added to link the transformers so customers won’t lose power during repairs or failure to one of the transformers.

A team of 25 PG&E employees and contractors did more than just add capacity.

They also constructed a new pond, a kind of ditch that collects and drains rainwater and in the event of an equipment failure could hold the thousands of gallons of oil that cools the internal workings of the substation transformers. And they rebuilt the fence around the perimeter of the facility to make it more secure and safe for the public.

Perhaps most significant was adding more modern, fully automated technology so PG&E employees can better monitor and remotely control the equipment.

PG&E is committed to providing customers with safe and reliable electricity. Hypnar said new priorities have emerged since the substation was built.

“Things were different,” Hypnar said. “PG&E in those days was reacting to providing new power to customers coming in and it was critical to get them that power. And so they built substations. Today, people are still demanding power but we also want to make sure that it’s reliable. More capacity, greater reliability.”

PG&E partnering with communities to minimize customer impact


Sectionalized breakers were added to link the transformers so customers won’t lose power during repairs or failure to one of the transformers.

Hypnar added that he has great satisfaction seeing the upgrade come to a close. He’s currently helping design a similar project in Sunnyvale where PG&E is modernizing a substation to accommodate an expanded campus for Juniper Networks, which manufactures computer networking equipment.

Don Hall, a San Jose-based customer care director for PG&E, pointed to expanded campuses for Google in Mountain View and Apple in Cupertino. Those are projects, he said, that require partnering with PG&E to ensure there’s adequate electric capacity and reliability.

“Much of what we’re seeing is a concentration of energy consumption,” Hall said. “That challenges a utility like PG&E to be able to keep pace in an area where reasonable urban density already exists.”

In some cases that means building new substations. In other areas, like in Campbell, it requires upgrading the existing facility. Either way, he said his team’s priority is to work with communities when projects are being planned to minimize impacts to important construction work.

“We really want to emphasize our community presence and do as much outreach as possible,” Hall said. “We hope that customers understand the work we’re doing and appreciate the work we’re making to improve service and reliability.”

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