Solar array up and running at transfer station

This new facility, now up and running, will generate about 172,000-kilowatt-hours of electricity per year.

This spring, King County’s Solid Waste Division worked with local installer Western Solar to build the new array – a connected network of 348 solar panels – on previously unused land next to the transfer station.

This new facility, now up and running, will generate about 172,000-kilowatt-hours of electricity per year, the equivalent of 24 single-family homes.

This project was completed with the help of partners at the county and state level. The solar array was funded with significant support from a grant provided by Washington state’s Solar Grant Program, which provides funding for solar projects on public buildings such as the Vashon transfer station.

Stormwater Services, in King County’s Department of Natural Resources and Parks’ (DNRP) Water and Land Resources Division, played a pivotal role in the project by leading the stormwater planning and permitting. This permitting work ensures that the stormwater generated by the new facility will be properly managed to maintain clean water in addition to creating clean energy, and advances Clean Water Healthy Habitat Goals of protecting human, salmon, and orca habitats while also generating clean energy.

The Vashon solar array is just one of many projects aimed at reaching the County’s long-term climate goals. Last year, the Solid Waste Division completed a similar solar installation at the Enumclaw Recycling and Transfer Station. Both solar projects are included in the King County Strategic Climate Action Plan’s goal for 20 county projects to pursue Zero Energy or Living Building Challenge certification by 2025.

With the completion of the two solar facilities and other building improvements, the Enumclaw and Vashon recycling and transfer stations will both be eligible for Zero Energy certification. King County Parks also committed to a zero energy and solar projects as part of the climate action plan.

“The Vashon solar project is key to the Solid Waste Division’s goals of increasing sustainability in our operations,” said Cynthia Adams, operations supervisor for the division. “The project gets us closer to our goal of being carbon neutral in operations by 2025.”

The project is also a step toward the County’s overall efforts to make 100% of capital projects carbon neutral by 2030.

Doug Williams, the media relations coordinator for King County’s DNRP, said that he does not have any knowledge about any additional solar arrays planned for his department’s properties on Vashon.

“The transfer station is in kind of a unique position – it’s got all of that open space around it, and it also has a significant amount of energy need – primarily the trash compactors, which are used to maximize each load when it leaves the island, so it made sense to pursue solar at that facility,” Williams said.

To see a video about the solar array on Vashon, visit