PG&E Larkin Substation

A Net Zero First for PG&E

client

Pacific Gas & Electric Company
location

San Francisco, CA
size

12,200 SF
sustainability

Net-Zero Energy

TEF expanded PG&E’s original 1962 electrical substation in San Francisco’s Tenderloin, its fourth improvement to the utility’s substation infrastructure. The net-zero switchgear building earned a rare distinction: certification by the International Living Future Institute’s Zero Energy Building program, the first of its kind in the United States.

Tall vertical living wall framed by patterned metal façade panels with integrated lighting, above concrete service doors and landscaped planting beds.

Architectural detail of perforated metal façade panels and a screened service enclosure, with linear lighting highlighting the patterned surface.

Advancing Environmental Stewardship

TEF achieved net-zero performance through an integrated set of passive and renewable strategies. A 60 kW rooftop solar array offsets the building’s energy consumption, while fresh filtered outside air and natural convection, aided by strategically placed exhaust fans, maintain ambient temperatures for the electrical equipment. Large vents at the building’s base draw on San Francisco’s cool climate to eliminate the need for artificial cooling, reducing the energy load by nearly 40 percent. High-efficiency LED lighting, fossil-fuel-free systems, and two bioretention planters completed the building’s sustainable profile.

Solar panels mounted above a patterned metal building façade, with neighboring urban buildings visible in the background.

Inspired by the Power Grid

The addition features a rainscreen that combines three types of individually modeled glass-fiber-reinforced-polymer panels into a faceted façade inspired by a map of the substation’s service area. The façade casts changing patterns of light and shadow across its surface throughout the day and year, an ever-changing expression of the sun’s energy. At night, light fixtures embedded in the sloped panels pulsate across the building, expressing the city’s dynamic electrical power grid. The result lends aesthetic relief to the surrounding urban fabric and gives the utility building a distinct presence.

Close-up of angled, ribbed metal façade panels casting deep geometric shadows in bright sunlight.

Illuminated utility building façade at dusk with patterned metal panels, a vertical living wall, and a screened service area along the sidewalk.

Street view of a utility building with perforated metal screening, integrated lighting, a vertical living wall, and pedestrians moving along the sidewalk.

Serving the Grid, and the Community

The one-story-plus-basement addition safely houses critical electrical infrastructure along with storage and support space. Occupying a constrained, midblock site in the Uptown Tenderloin Historic District, the project is designed to strengthen energy reliability throughout the city while enhancing the surrounding community. The perpendicular addition to the existing substation accommodates the need for crane and equipment-lift access, while a towering green wall, planted in a geometric pattern that echoes the faceted façade, provides biophilic relief to the dense, notoriously gritty neighborhood. The project marked the fourth in a series of TEF-designed improvements to PG&E substations.