Wärtsilä supplying 2 GWh energy storage portfolio to Clearway solar projects

Clearway Energy Group’s Mililani Solar Project on Oahu, Hawaii. Wärtsilä is supplying an energy storage system for the project. (Courtesy: Clearway Energy Group/Wärtsilä)

Wärtsilä has signed contracts to deliver energy storage systems totaling 500 MW/2 GWh to five Clearway Energy Group solar projects in California and Hawaii.

The portfolio includes the Daggett 2 & Daggett 3 projects. These combined make up the largest co-located photovoltaic and storage facilities in California at 482 MWac solar PV and 275MWac/1.1GWh of energy storage. 


Subscribe TodayTo the all-new Factor This! Renewable Energy World Podcast. This podcast is geared specifically towards the solar industry. Whenever you get your podcasts.

Listen to the most recent episode Nextracker CEO Dan Shugar.


The Daggett projects can be found in San Bernardino (California), near a former coal- and natural gas plant. Construction on both projects has begun with completion expected in 2023.

Clearway Energy Group celebrated in April 2021 the groundbreaking of the Mililani I Solar Power and Waiawa Solar Power project. Clearway Energy Group.

Two projects, comprising 75 MWac / 300 MWh of energy storage, are being installed at Clearway Energy Group’s Mililani I Solar and Waiawa Solar Power facilities on the Island of Oahu in Hawaii. 

Construction is expected to be completed by 2022.

The portfolio’s fifth project is a 147MWac/588MWh energy storage system. It will be connected to the Kern County, California, 192MWac Rosamond Central solar PV plant.

The energy storage system will improve the efficiency of the solar facility by providing ancillary services, including solar shifting, to the California Independent System Operator.

Construction of Rosamond Central is expected to be completed by December 2023.