Greenwater battery energy storage system (BESS) in Pierce County, Washington reached a US$400 million financial close on December 3, 2025 as BrightNight and Cordelio Power continue development for the 200 MW/800 MWh project. This also gives confidence in readiness to provide grid services to Puget Sound Energy (PSE). The project also supports Washington’s renewable energy transition, integration and diversification as the state continues with the development of project like Ostrea solar project and Orion nuclear fusion power plant.

BrightNight described the project as a ‘major step forward’ in modernizing the Pacific Northwest grid. The project is also a show-case of combining storage and digital infrastructure capabilities. The company also continues to grow its flexible dispatch portfolio in the U.S. through Greenwater battery storage project.

Factsheet for Greenwater Battery Storage (BESS) Project in Washington

Developer: BrightNight and Cordelio Power

Location: Pierce County, Washington

Capacity: 200 MW/800 MWh

Technology: Lithium-ion batteries

Offtaker: Puget Sound Energy (PSE)

Interconnection: PSE’s White River Substation

Project Financing: USD 400 million committed by a syndicate including Royal Bank of Canada, Crédit Agricole CIB, CoBank, National Bank of Canada, and Zions Bank.

Status: Financial close reached. Development phase underway. Construction planned to align with 2026 commissioning date.

Development Activities: Underway

Expected Commissioning Date: 2026

Project Timeline

August 2024: City of Sumner approves Conditional Use Permit for transmission infrastructure for Greenwater BESS project.

February 2025: Cordelio confirms BESS procurement for expansion of storage pipeline. Greenwater is also included among planned deliveries.

December 2025: BrightNight and Cordelio announce 400 million dollars financial close on Greenwater. The financing unlocks capital for construction and commissioning.

2026 Onward: Construction and commissioning.

Outlook on Greenwater Battery Energy Storage System (BESS) Project in Washington

Greenwater BESS project represents a milestone for large scale battery energy storage systems in the United States. The 200 MW/800 MWh standalone battery system contracted to supply firm capacity to PSE is now fully financed for construction and commissioning. As 2026 approaches, the utility of battery storage projects continues to be cemented through helping with energy variability from renewables to supporting grid reliability.

The momentum behind utility-scale storage is being matched by growth on the supply side. While projects like Greenwater expand operational capacity on the grid, manufacturers are scaling up to meet the surging demand. NeoVolta’s planned BESS production facility in Pendergrass, Georgia, exemplifies this shift—aiming to bring 2 GWh of new annual manufacturing online by 2026 and strengthen domestic capability for future large-scale deployments.