Danish renewable energy company Ørsted and US utility Salt River Project (SRP) have confirmed that their 300MW solar-plus-storage project in Pinal County, Arizona, has commenced operations.
The Eleven Mile Solar Center is situated just south of the state capital, Pheonix, and includes a co-located 4-hour duration 300MW/1,200MWh battery energy storage system (BESS).
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Readers of sister site PV Tech will be aware that technology giant Meta signed a power purchase agreement (PPA) with the project owners last year to secure the “majority” of the power generated from the solar PV power plant. Meta confirmed that the green energy would be used at a data centre in Mesa, with the remainder being made available to SRP customers in the region.
The project’s battery storage system is the largest in Arizona to date. The Southwest US state was ranked in the top three among states for grid-scale storage deployments in Q2 2024, as found by Wood Mackenzie in the research firm’s quarterly US Energy Storage Monitor report.
Eleven Mile Solar Center represents an approximate US$1 billion investment by Ørsted in clean energy for Arizona. The company said it will generate approximately US$80 million for public services in the form of tax revenue for the local community.
Alongside this, the project also supported the US economy by employing domestic companies to support its development. These included US thin-film manufacturer First Solar, energy storage integrator Fluence and Nextracker, a PV tracker manufacturer.
‘Exciting’ project a taste of things to come, says Fluence Americas president
In a recent interview with Energy-Storage.news, John Zahurancik, Americas president for battery storage technology provider and system integrator Fluence, namechecked the “exciting” project as one of the company’s recent highlights.
Zahurancik said Fluence was seeing similar opportunities for building “very large-scale systems” elsewhere in the US.
“We’re seeing some of that come into the space where the power consumption of these large data centre customers, coupled with their desire to have green power, is driving some of the storage and renewable business quite a lot [in the US],” Zahurancik said.
The hybrid solar-plus-storage project takes the title of hosting the ‘biggest operational Arizona BESS’ from another Salt River Project solar-plus-storage plant, Sonoran Solar Energy Center.
That project pairs 260MW of solar PV with a 260MW/1,000MWh BESS and went online in March. Developed by NextEra Energy Resources, Sonoran Solar Energy Center will provide power for another tech giant’s data centre needs, Google’s facility in Mesa which is in construction.
Arizona: ‘One of the highest growth rates in the country for electricity demand’
Salt River Project and other utilities in the state, notably Arizona Public Service (APS) are signing waves of long-term off-take agreements for solar-plus-storage resources, and Tucson Electric Power is seeking to build its own 200MW/800MWh BESS asset, the second of the same size from that utility.
Sonoran and Eleven Mile are the first gigawatt-hour scale battery systems in Arizona but could be followed by others of comparable size: last month, institutional investor Copenhagen Infrastructure Partners (CIP) closed financing on a 1GWh standalone BESS project in the state.
“Arizona has one of the highest growth rates of electricity in the country due to the surge in data centres and the reshoring of American manufacturing. With our first project in Arizona now complete, we’re thrilled to help meet the growing demand of the state and region with reliable, domestic energy,” Ørsted Americas CEO David Hardy said of Eleven Mile Solar Center.
A couple of months ago, Ørsted formalised a partnership with developer Mission Clean Energy to work on BESS projects in the US Midwest states, targeting 1GW of developments in Midcontinent Independent System Operator (MISO) territory.
A version of this story first appeared on PV Tech.
Additional reporting for Energy-Storage.news by Andy Colthorpe.