Contractors for Pacific Gas and Electric Co., in partnership with Groveland Community Services District, are planning to break ground this week on the installation of a microgrid location for emergency backup equipment to provide power to downtown Groveland during forced blackouts, which PG&E calls public safety power shutoffs.

The new Groveland Permanent Interconnection Hub will occupy a section of existing public parking next to GCSD/Cal Fire Tuolumne County Station 78 and Mary Laveroni Park on Main Street, which is Highway 120 in Groveland. A microgrid site in Arnold is also being developed, according to PG&E.

Workers on-site Monday unloaded tools, including a pavement cutting machine, and materials for the project before noon. They used a Bobcat skid-steer loader to offload the pavement cutter from a truck, and they had a Bobcat backhoe excavator on-site as well. A half-dozen contractors and workers met for a time to discuss plans and safety at the work site. They expected to break ground on the project later Monday or later this week.

Pacific Gas and Electric and the PG&E contractors are projecting it will take 38 days of work to complete the project, Roni Lynn, a public relations representative for Groveland GCSD, said Monday. On that schedule, Lynn estimated the project will be complete by March 31.

Asked how much money PG&E is spending on the project and how much total is budgeted for it, Pete Kampa, GCSD general manager said, “There is no money coming from GCSD for this project, and PG&E compensated the district for the easement rights to build the facility.”

Describing the microgrid project in a press release, GCSD staff said PG&E contractors will be enclosing the western portion of the parking lot next to Station 78, including road access and the grassy area around a flagpole at Station 78, with temporary perimeter fencing.

The new Groveland Permanent Interconnection Hub — a longer name for the new microgrid facility — is expected to be able to supply power to most of the businesses in the downtown Groveland area during future PG&E public safety power shutoffs, according to GCSD staff.

Power will be supplied by portable, low-emission, high-efficiency generators hauled to the site by PG&E and connected directly to the Groveland Permanent Interconnection Hub at Mary Laveroni Park, which is run by GCSD.

Groveland is the first community in Tuolumne County designated to have the service offered by PG&E, GCSD staff said Monday. Groveland is also the only community in Tuolumne County currently designated to have the service offered by PG&E, because downtown Groveland is one of the only places in the county with existing underground power lines, Lynn said in August.

PG&E is paying for the permanent microgrid equipment and for the generators when they become necessary, Kampa said in August. PG&E is also paying GCSD $25,300 for three easements, slivers of Mary Laveroni Park that add up to 5,887 square feet, for where the microgrid equipment and space for trailered-in generators to be parked and fired up to make electricity.

Kampa said PG&E will dig up part of a parking lot and install more underground grid gear for safety. Temporary fencing will be put around the microgrid gear and the trailered-in generators when the site is in use during public safety power shut offs.

A PG&E representative was at an Aug. 11 GCSD board meeting to talk about the microgrid project. Business owners who took part in that meeting included Jenn Edwards, co-owner of Groveland Hotel; Brennen Jensen, co-owner of Hotel Charlotte; and Elizabeth Barton, a founding member of Echo Adventure Cooperative, which offers tours, retail fly fishing gear, and guided trips in Yosemite, Lynn said.

The existing underground power lines that serve downtown Groveland have been in place for about two decades, Kampa said in August. The lines serve about 30 properties, including hotels, restaurants, the post office, a commercial center, the fire station, the ambulance garage, chiropractic and medical offices, banks, the public library, museum, community center, and youth center. 

The plan is to set up permanent space in an area off Main Street for microgrid equipment that includes a switching mechanism that will be able to take electricity from temporary generators to be trailered in by PG&E, when public safety power shut offs become necessary due to forecasts for high winds and fire dangers.

The microgrid gear will then connect to underground lines to reach customers. Kampa said PG&E will build one underground line to the Adventist Health Clinic and ambulance building, a block from Main Street, which is also Highway 120 in downtown Groveland.

As much as 95% of the power lines serving the downtown Groveland area along the Main Street corridor are already underground, Lynn and Kampa estimated. The microgrid setup is considered safe and effective because it powers only underground lines, which can be juiced during high wind events, according to Lynn and Kampa.

Public safety power shut offs have been adopted by PG&E due to multiple catastrophic wildfires in recent years sparked by PG&E equipment and power lines contacting trees.

In December 2019, PG&E proposed to settle all claims from the 2015 Butte Fire in Calaveras County; the December 2016 Ghost Ship warehouse fire that resulted in 36 deaths in Oakland; the October 2017 Tubbs Fire that burned more than 5,600 structures and killed at least 22 people in Wine Country; and the November 2018 Camp Fire that burned up 18,800 buildings and killed at least 85 people in Butte County, for a total of $13.5 billion.

The offer was intended to help PG&E avoid bankruptcy, but that happened anyway.

Public safety power shut offs are unrelated to flex alerts and rolling outages that take place in California from time to time.

In June, PG&E received approval from the California Public Utilities Commission for microgrid proposals intended to reduce the number of customers affected by public safety power shutoffs and to mitigate impacts on those affected by public safety power shutoffs.

The company said in June they intended to build 10 microgrid sites and have them ready to energize by the end of last year. Asked for an update Monday on how many microgrid sites have been built and where, Megan McFarland with PG&E marketing and communications shared a list that shows operational temporary microgrid sites in Angwin and Calistoga in Napa County; Clearlake North and Clearlake South in Lake County; Colfax in Placer County; Placerville in El Dorado County; and Shingletown in Shasta County.

Microgrid sites in development included Groveland in Tuolumne County; Arnold in Calaveras County; Foresthill in Placer County; Georgetown and Pollock Pines in El Dorado County; Magalia in Butte County; and Lucerne and Middletown in Lake County.

The Groveland site will consist of a transformer and associated interconnection equipment; ground grid; and grid isolation and protection devices, also known as reclosers and switches, that, when operated with temporary generation, will prevent energization of distribution assets in Tier 2 and Tier 3 fire threat zones, leaving only select Tier 1 fire threat zones to be energized. McFarland said project costs are confidential.

Contact Guy McCarthy at or 770-0405. Follow him on Twitter at @GuyMcCarthy.

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