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ContourGlobal breaks ground on 509 MWp solar plus 1.4 GWh storage project in Arizona backed by Tesla PPA

ContourGlobal has started construction on Project Sterling, a 509 MWp solar and 360 MW / 1.4 GWh battery facility in Mohave County, Arizona, with a long-term power purchase agreement covering about 90% of output signed with Tesla. The plant is designed to deliver dispatchable clean power for up to 16 hours a day and produce more than 1.1 TWh a year.

By Greener Numbers Editorial Team · Published October 19, 2026 · Updated 10/19/2026

ContourGlobal celebrated the start of construction on October 6 of Project Sterling, a hybrid solar-plus-storage facility roughly 20 miles north of Lake Havasu City in Mohave County, Arizona, the company announced October 7. The plant will combine 509 MWp / 450 MWac of solar PV with 360 MW / 1.4 GWh of battery storage across more than 2,000 acres in the Mojave Desert, with construction continuing through 2028 and an average of approximately 400 workers on site.

Once completed, the site will host more than 760,000 solar modules and over 300 battery containers using liquid-cooled lithium iron phosphate technology with integrated fire protection. Sterling is expected to generate more than 1.1 TWh of clean electricity a year - comparable to the yearly residential demand of a city of 100,000 to 120,000 people - making it ContourGlobal's largest renewable asset worldwide.

A long-term power purchase agreement with Tesla covers around 90% of expected output. ContourGlobal describes it as its largest PPA to date and one of the largest corporate solar-plus-storage PPAs ever signed for a single hybrid plant in the United States. The plant is engineered to deliver reliable clean power for up to 16 hours a day by storing solar generation for delivery after sunset.

The project is privately financed; ContourGlobal secured an Equity Bridge Loan from a syndicate of international banks to fund part of its equity commitments during construction. Access comes via Polaris Road, a new 5.2-mile route connecting the site to historic Route 66 between Topock and Kingman, and power will flow through the Western States power interconnection, with the Western Area Power Administration represented at the groundbreaking.

Following the recent completion of Black Hollow Sun in Colorado, ContourGlobal's U.S. portfolio now totals 2.4 GW in operation or under construction: 1.2 GW of thermal generation across 10 plants in California, New Mexico and Texas, plus 1.2 GW of renewables and storage including 324 MWp of operating solar PV and Project Sterling.

Official source: contourglobal.com ↗