Orcas Center Microgrid
Eastsound, WA · Orcas Center · 2025
Solar Builder Magazine Project of the Year 2025, Microgrid category
134 kW DC solar · 150 kW / 1,376 kWh storage · 150 kW propane generator · EV charging
Purpose
Orcas Center is the island's main cultural and gathering space, and before the microgrid, it couldn't operate through an extended outage. Orcas is in the San Juans, and in a large-scale emergency, the island is on its own. The system now carries the Center’s entire load on solar, battery, and generator. San Juan County Emergency Management worked on the design alongside the Center, so the building functions as an emergency annex under the county's emergency plan.
Challenges
The roof couldn't carry the full array, so the design splits it between flush-mounted rooftop modules and pitch-optimized ground mounts that raise generation and improve seasonal output. Then the island asserted itself. A geotechnical study had indicated the ground mounts could be driven on ground screws, but nine of the first ten hit bedrock and refused on day one. The foundation was redesigned as a strip concrete footing that serves as ballast and doesn't require the same depth of penetration. Nothing on Orcas was rated to lift the battery system off the truck, so we had to ferry a telehandler over. Commissioning then took several trips back from the mainland by ferry or plane. It was a logistical challenge, but in the words of our VP of Construction, “every challenge is an opportunity for success”.
The microgrid runs autonomously when islanded, with the FieldSight controller sequencing solar, battery, and the 150 kW propane generator so critical loads stay up without anyone on site to manage the handoff. The system also exchanges data with OPALCO's distributed energy resource management system, letting the cooperative test peak shaving and voltage support through it; it is the first community microgrid in the San Juans tied into a utility DERMS. The contract was fixed-price and paid against Climate Commitment Act grant milestones, so scheduling, documentation, and invoicing tracked the funding as closely as the build. It finished on budget.
