Willis Battery Storage

Willis Battery Storage is a 20 MW grid-connected lithium-ion battery energy storage project located in Chateaugay, Franklin County, New York, approximately 40 miles northwest of Plattsburgh. The facility consists of five 53-foot walk-in battery enclosures, each containing more than 19,500 batteries arranged in modules and racks, with each enclosure rated at 4 MW. The system includes inverters, transformers, a control house, and backup generator connected to the Willis substation at 115 kV. The project stores excess renewable generation and discharges during peak demand periods to relieve transmission congestion, support renewable energy integration, and supply the New York wholesale energy and ancillary-service markets. The facility is owned and operated by the New York Power Authority and maintained by the St. Lawrence-Franklin D. Roosevelt Power Project.