Washington State’s Snohomish County Public Utility District is preparing to bring a large-scale battery energy storage system online in Arlington in fall 2026, even as several King County communities have paused similar projects, highlighting a growing divide over the future of energy storage.
Utilities see large batteries as an important way to store clean electricity and lower costs when demand surges, while some residents remain concerned about safety risks.
What’s happening?
In fall 2026, the Snohomish County Public Utility District plans to bring online a large-scale battery energy storage system that KNKX described as Washington’s first and largest. The project is expected to add enough grid capacity to supply many thousands of homes for several hours.
While opposition has grown in other places, Arlington has a policy meant to support permitting for projects like this one. That has allowed the utility to move ahead with the project at its clean energy campus, where Tesla-made batteries are housed in vented white enclosures spread across a gravel lot…