PUD Energy Storage Program
Background/Why Energy Storage?
The PUD has installed three battery storage systems as part of a multi-year program aimed at transforming the marketplace and how utilities manage grid operations. These battery storage systems are the first to be built using the cutting-edge Modular Energy Storage Architecture (MESA). The PUD’s first battery storage system is a pair of lithium-ion battery storage systems located at a utility substation near the PUD’s Operations Center. A second system, a 2.2 MW/8 MWH vanadium flow battery storage system was installed in early 2017 in a utility substation in downtown Everett near the PUD’s Headquarters. The third energy storage system is a 1 MW/1.4 MWH lithium-ion battery storage system, part of the new Arlington Microgrid and Clean Energy Technology Center.
The installations are designed to improve reliability and the integration of renewable energy sources, which are rapidly growing in the Pacific Northwest.
The PUD recognizes that the electrical grid needs to change to take on more renewable power. MESA’s standards-based energy storage systems and software will play major roles in that change. MESA provides standard interfaces between equipment components such as the power conversion system, batteries and control system. It brings more choices for utilities, reduces projects’ complexity and promises to lower costs. The system offers a non-proprietary and scalable approach to energy storage.
Energy Storage Projects
The program, which forges partnerships with major U.S. and international business partners, includes the first set of two large-scale lithium ion batteries, one manufactured by GS Yuasa International Ltd. and supplied by Mitsubishi and a second manufactured by LG Chem. Both lithiumion batteries utilize a Parker Hannifin Power conversion system. The PUD also deployed the set of advanced vanadium flow batteries, built by UniEnergy Technologies, at a second PUD substation. Both systems include software and system design by Doosan GridTech.
The PUD’s third battery storage system project demonstrates how energy storage can provide grid resiliency and renewable energy integration in a microgrid, a locally grouped electricity sources that can feed the main electrical grid and also be disconnected to serve a specific location. The Arlington Microgrid is designed and sized to provide power to the PUD’s future Arlington Community Office during an outage.
The utility is managing its energy storage projects with an Energy Storage Optimizer (ESO), a software platform that runs in its control center and maximizes the economics of its projects by matching energy assets to the most valuable mix of options on a day-ahead, hour-ahead and real-time basis.
The PUD’s energy storage projects were made possible in part by a substantial investment from the Washington State Clean Energy Fund. The two MESA projects received $6.6 million in reimbursement from the Clean Energy Fund, while the Arlington Microgrid project received $3.5 million from the fund.
The PUD also received an additional $1 million from the Clean Energy Fund for a partnership with the Bonneville Power Administration and the University of Washington to optimize the use of energy storage and demand response. The project will model how these assets may be used to move energy to:
- Mitigate both technical and economic costs of congestion
- Improve the reliability and operating costs of BPA’s transmission grid