Clearway Energy, a renewable energy developer and independent power producer (IPP), has opened its first utility-scale solar+storage project on the island of Oahu, Hawaii, according to foreign media reports.
Clearway has said that the project cost US $140 million and that its installation was completed ahead of schedule and announced the opening of the Mililani SolarI solar+storage project.
Hawaii Governor David Ige attended the unveiling ceremony and toured the project on August 11
The project deploys a 39MW solar farm with a 39MW/159MWh battery storage system.Clearway signed separate 20-year Power Purchase Agreements (PPAs) with Hawaiian Electric Company (HECO) in 2018 for the Mililani SolarI Solar+Storage Project and the Waiawa Solar+Storage Project ( The PPAs are for the Waiawa Solar Solar+Storage project, a 36MW solar power facility and a 36MW/144MWh battery storage project, each operated independently on Oahu.
According to industry press reports, construction of both projects began in April 2021, with Moss Solar, the solar power division of local infrastructure developer Moss, becoming the constructor for both projects.
Finnish energy storage system integrator and manufacturer Wärtsilä is supplying battery storage systems for both projects. Wärtsilä announced in July that it would supply storage systems for Clearway's O'ahu energy storage project and for three solar+storage projects developed by Clearway in California.
The three battery storage projects developed by Clearway total 500MW/2,000MWh and all three battery storage systems are being deployed in conjunction with solar generation facilities, with one of the solar+storage projects retrofitting an existing solar farm and the other two new solar+storage projects being located adjacent to two decommissioned fossil fuel-fired power plants in San Bernardino County, California. in San Bernardino County, California. These projects are scheduled to come online next year.
The only application for Clearway to open this solar+storage project in Hawaii is energy transfer, Andy Tang, Wärtsilä's vice president of energy storage and optimisation, said in a recent industry press interview, adding that the four-hour battery storage system will store power generated during the day and apply it at night.
For Clearway's project, Wärtsilä is offering the GridSolve Quantum battery storage solution developed by the company, as it does for all its battery storage projects. the GridSolv Quantum solution also includes the GEMS digital energy platform energy management system (EMS) and will be equipped with lithium iron phosphate (LFP) batteries.