Sunnyvale Civic Center Microgrid

About the Project

Sunnyvale City Hall stands as the centerpiece in the City’s reimagined Civic Campus, one part of the larger Civic Center Modernization Phase 1 project. The new 118,000 SF, four-story building enables the city to collocate all departments under one roof. Its north façade meets the edge of Olive Avenue, inviting the community inside for easy accessibility to city services, from a one-stop permit center to the public works department. The modern council chamber creates an intimate, fully accessible space beneath a wood ceiling that mimics sunlight filtering through tree leaves. A curving central stair in the lobby encourages movement and exploration, while calm, light-filled workspaces and outdoor terraces provide opportunities to work in nature. Departmental offices span the floors and include smart conference and training rooms. Every space features durable, high-performing materials free of harmful chemicals and integrate sustainable lighting and shade solutions.

The new City Hall building includes a microgrid system that allows the building to operate not just from the generator but to switch to the 680 kilowatts (kW) photovoltaic array and 250-kW-per-hour (kWh) battery energy storage systems. The microgrid provides the capability to keep critical departments running for days, depending on the output of the array. By leveraging solar power stored during the day, the system provides the capability to maintain essential services, including emergency response, public safety coordination and city operations for multiple days without reliance on the external grid. Sunnyvale City Hall is a model for sustainable civic design, showcasing its solar array proudly and achieving Net Zero Energy performance and LEED Platinum Certification.

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Quick Facts

Location Sunnyvale, California
Client City of Sunnyvale
Architect SmithGroup
Industry Power + Energy
Line of Business Construction
Delivery Method Design-Bid-Build
Completion Date January 2024
Contract Value $ 192,000,000
Sustainability LEED Platinum
Square Footage 142,000

Challenge

During the integration of the Sunnyvale Civic Center microgrid, Hensel Phelps’ team faced a critical coordination challenge involving Pacific Gas & Electric Company (PG&E)’s interconnection and permanent power requirements. The system integrated utility power, photovoltaic generation, battery energy storage and emergency generation, requiring each component to operate together while meeting PG&E requirements. Multiple rounds of utility review, including additional requirements for electrical meters and disconnects, extended the approval process and affected the timing of commissioning and demolition activities.

The delays created a direct impact on the project’s ability to advance key work at the Civic Center. Commissioning the microgrid required the main switchboards, generator and other systems to be operational. At the same time, work had to be coordinated around an occupied City Hall and the demolition of the old building. With limited opportunities to test the system and permanent power activities dependent on utility coordination, the team needed to find a way to maintain progress without compromising the overall project sequence.

Solution

The project team worked collaboratively with PG&E, the city and project stakeholders to identify the utility-related issues and develop a path forward. The team coordinated and sequenced key inspections, evaluated requirements with PG&E and identified temporary power solutions that allowed critical activities to continue while permanent power and interconnection items progressed.

At the same time, the team used in-person working sessions to help the City and stakeholders understand how the microgrid system would operate across different power modes and which systems would be supported during an outage.

Results

Sunnyvale City Hall is a model for sustainable civic design, showcasing its solar array proudly and achieving Net Zero Energy performance and LEED Platinum Certification. The completed microgrid further strengthens the facility’s energy strategy by integrating photovoltaic generation, battery energy storage, utility power and emergency generation into an automated system designed to optimize energy use during normal operations and provide resilient power during utility outages.

The systems enable the Civic Center to utilize on-site renewable energy and battery storage while maintaining access to emergency generation when needed. Together, these capabilities support more efficient energy use and provide greater operational resilience during utility outages, demonstrating how advanced energy systems can be integrated into a high-preforming civic facility.

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