Tumwater Planning Commission recommends development of regulatory framework for battery energy storage systems 

The Tumwater Planning Commission has backed the idea of developing a regulatory framework for battery energy storage systems. 

The commission made the decision came after a presentation on  May 26 from city staff, who proposed several options for regulating the storage systems. 

Sustainability Manager Alyssa Jones Wood said battery energy storage systems provide backup power during outages.

Jones Wood noted the systems are not tied to a single fuel source because the systems can draw power from the grid or from direct connections to renewable energy sources. 

Developing a local code 

Associate Planner Dana Bowers said production and installation of the systems are regulated by international, federal and state-level legal frameworks. 

Olympia, Lacey and Thurston County have been working on their own regulations based on a model code developed in collaboration with local fire departments. 

Jones Wood said because the city lacks a local code, battery energy storage systems already used in homes are permitted through the Washington State Labor & Industries, leaving the city unclear about exact locations. 

Bowers added the absence of local regulations allows utility scale operators to opt for a state-level review process through the Washington State Energy Facility Site Evaluation Council. 

She said to develop a framework for battery energy storage systems in Tumwater, the city would have to address the following factors: a system’s battery capacity, siting considerations, incompatible land uses, and whether it would be used as backup power for homes and establishments or if it would be used to support the power grid. 

Bowers detailed three tiers for dividing batter systems based on capacity. 

• Residential scale systems, which could accommodate up to four separate 20 kilowatt hour units. 

• Medium scale systems, which could accommodate up to 600 kilowatt hour units for commercial and government infrastructure. 

• Utility scale systems, which would be used to support substations. 

Siting, design standards  

As for where the systems would be allowed, Bowers said residential scale systems could be allowed in all zoning types, while medium scale systems could be limited to nonresidential zoning types. 

For utility scale systems, Bowers noted Tumwater lacks a dedicated "utility level" zone district, meaning the systems must be permitted across a wide spectrum of existing districts to remain close to substations.

Bowers said the city would have to prohibit utility scale systems in open spaces, rural sensitive zones and residential sensitive resource areas.

She added the city could add protections to high density residential and manufactured housing areas to reduce the risk of fire in densely populated areas. 

The presentation also covered setback requirements, safety standards and visual factors. 

While the National Fire Protection Association (NFPA) mandates a 10-foot separation from larger battery energy storage systems, Bowers said staffers want to apply the city’s own setback requirements for substations. 

During planning and permitting, proposals for utility scale systems could be required to have an emergency management plan that must be approved by the fire marshal. 

Proposals for medium scale systems would not need to have an emergency management plan, but must also be reviewed by the fire marshal. 

Residential scale systems would continue to be regulated externally by Washington Department State Labor & Industries. 

In terms of design, all battery classifications could be bound by existing design guidelines for other mechanical equipment. 

Utility scale systems would also be required to maintain a "fire-wise" landscape to reduce the spread of fire, along with an NFPA-compliant 7-foot perimeter security fence and standard safety signage.  

Commissioners also proposed requiring fencing for medium scale operators. 

Decommissioning, ownership transfer 

Staff also addressed what would happen after the decommissioning of a battery energy storage system. 

While residential scale systems would require no formal oversight when they are no longer used, city staff is looking to require medium scale operators to recycle electrical components after the decommissioning of systems. 

For utility scale systems, city staff could ask for comprehensive decommissioning plans as required by NFPA. 

Should a transfer of ownership happen, Bowers said the city would obligate new owners to sign off on existing agreements tied to the system. 

Safety risks 

Bowers said the next step would be to present the same concepts to the Tumwater  City Council at a meeting on June 9 to determine whether the council would like to proceed with the development of the code. 

Commissioner Elizabeth Robbins noted the presentation detailed a lot about benefits, but not about the risks of battery energy systems. 

Robbins requested staff also highlight the risks by presenting data detailing historical failures, cases of hazardous material leaks, fire frequencies and other incidents. 

She also pointed out that widespread adoption could create a net draw on the electrical grid unless a battery is connected to a renewable energy source. Robbins requested staff also gather data to determine the long-term impacts of the battery energy systems on the grid. 

Jones Wood acknowledged the inherent safety risks of battery energy storage systems, but said there are multiple layers of fire regulations to reduce the risks. 

She added that battery energy storage systems have built-in fire suppression, and utility scale fire incidents are rare. 

Jones Wood said staff is working with Tumwater  Fire Department Chief Brian Hurley and the city's building officials to get them fully involved in the process.