Energy Storage

Snohomish PUD breaks ground on $9.5 million microgrid project

Snohomish County Public Utility District in Washington state plans to demonstrate new energy technologies, including energy storage coupled with a solar array, at its $9.5 million Microgrid and Clean Energy Technology Center on which ground was broken earlier this week near the Arlington Airport.

Once in operation in 2020, it will be Snohomish’s first microgrid and third battery storage facility, according to Neil Neroutsos, spokesperson for the Everett-based PUD.

The system will be able to run independently from the electric grid.

The microgrid also will demonstrate how PUD electric fleet vehicles can be used to benefit the electric grid via a vehicle-to-grid system that allows both charging from the grid and discharging to the grid.

“In addition to the value this project will create in terms of grid resiliency and a new solar option for our customers, the system also will provide a range of educational opportunities for schools, the business sector, energy industry researchers, and local agencies,” PUD commissioner Sid Logan said.

The project’s Clean Energy Technology Center is aimed at supporting a range of science, technology, engineering and mathematics education efforts in the community.

Snohomish PUD serves 348,000 electric and about 20,000 water customers over a 2,200-mile area of Snohomish County and Camano Island.

In 2017, the PUD sold more than 8.8 million megawatt-hours of electricity, Neroutsos said.

Brian Bonlender, director of the Washington State Department of Commerce, said the project is another step forward in modernizing Snohomish's electric grid. “Together, we’re strengthening communities by creating resiliency and flexibility through these new microgrid applications,” he said.

The Washington Clean Energy Fund, which is managed by the Department of Commerce, awarded a $3.5 million grant for the project.

At present, Snohomish relies on hydroelectric power for about 88% of its electricity needs, followed by wind at 6%, and about 5% from the market.

“We’re roughly 97% carbon free,” Neroutsos noted. Once several big coal-fired generating units in Montana close over the next decade or so, Snohomish expects to be 100% carbon free, he said. The coal units sell power into the regional market, and some of that electricity is used by Snohomish.

Snohomish's first energy storage system, launched in 2015, includes two large-scale lithium-ion batteries and is located at a substation near the utility’s main operations center. The second system, which went into commercial operation in 2017, is based on advanced vanadium flow technology. It is housed in 20 shipping containers at a PUD substation in downtown Everett.

The PUD’s systems are based upon modular energy storage architecture, which offers a non-proprietary and scalable approach to energy storage. It uses standard interfaces between equipment components, such as the power conversion system, batteries, and control system.