More residential, commercial, industrial and even governmental utility customers are becoming involved in self-generation projects (solar, wind, storage batteries, fuel cells, multisource microgrids, etc.) to reduce the costs associated with electric grid-generated power, as well as to ensure continuous power during grid outages. As a result, two utilities in Washington state are taking steps to back up their own power.


In December, Puget Sound Energy (PSE) and Renewable Energy Systems Americas signed agreements to cooperate in launching a battery-based storage project in Whatcom County that could eventually pave the way for larger scale efforts in PSE’s service territory. As part of the project, electricity will be stored in state-of-the-art battery modules as large as 40-foot shipping containers, containing the same amount of energy found in 1.7 million AA batteries. The unit will be capable of providing up to 18 hours of power during an outage for the core area of Glacier, Wash. (The average demand of the core part of the town is estimated to be 250 kilowatts.)


PSE is working with the state’s Department of Commerce on the pilot project. Last July, the department’s Clean Energy Fund awarded PSE $3.8 million to engineer and construct the 2-megawatt, 4.4 megawatt-hour lithium-ion battery unit.


The unit will also perform “peak shaving,” which involves harnessing electricity when customers’ energy consumption is low, storing it, and then releasing it back into the system when demand is high. The unit will also support greater integration of renewable generation, such as wind and solar.


Several miles southwest, at its Everett, Wash., substation, the Snohomish County Public Utility District dedicated its first battery-based storage system in January. This project was also funded with $7.3 million from the Department of Commerce Clean Energy Fund. It includes two large-scale, lithium-ion batteries. Later this year, the utility will deploy multiple advanced vanadium-flow batteries at a second substation.


The existing Snohomish units use modular energy-storage architecture (MESA), which provides a standard, nonproprietary and scalable approach to energy storage. The open standards approach is expected to result in the expanded application of plug-and-play energy-storage systems to help solve the increasing needs of today’s grid, which continues to depend more heavily on intermittent resources, such as wind and solar. Another goal of MESA technology involves developing standard electrical and communication interfaces to connect batteries, power converters and software components into modular energy-storage systems.