ContourGlobal Breaks Ground on 869 MW Solar-Plus-Storage Project in Arizona

ContourGlobal has commenced construction of a 509 MWp solar power project integrated with a 360 MW battery energy storage system in Mohave County, Arizona, USA, with Tesla as the offtaker under a long-term power purchase agreement.

ContourGlobal marked the start of construction of Project Sterling, a hybrid solar-plus-storage facility situated approximately 20 miles north of Lake Havasu City in Mohave County, Arizona. The project will integrate 509 MWp (450 MWac) of solar photovoltaic capacity with a 360 MW battery energy storage system offering 1.4 GWh of storage across more than 2,000 acres in the Mojave Desert, one of the sunniest areas in the United States. Construction is scheduled to continue through 2028, with an average workforce of around 400 people, providing a boost to the local economy.

Local construction crews will undertake civil engineering works, road development and site logistics to support the installation of more than 760,000 solar modules and over 300 battery storage containers, with a combined capacity of 360 MW and 1.4 GWh. The battery system will use advanced lithium iron phosphate (LFP) technology, incorporating liquid cooling and integrated fire protection. Once operational, Project Sterling is expected to produce more than 1.1 TWh of clean electricity annually, equivalent to the average yearly residential electricity consumption of a city with 100,000 to 120,000 residents. The facility will become ContourGlobal’s largest renewable energy asset globally. Under a long-term power purchase agreement, Tesla will purchase approximately 90% of the plant’s expected output, making the agreement one of the largest corporate solar-plus-storage PPAs signed for a single hybrid facility in the United States.

Project Sterling is connected to the Western States power interconnection, strengthening Arizona’s contribution to a more reliable and resilient regional electricity grid. Representatives from the Western Area Power Administration (WAPA) and the California Independent System Operator (CAISO) attended the project’s groundbreaking ceremony. The project is being developed with private financing. To support its financial structure and ensure efficient capital deployment throughout construction, ContourGlobal recently secured an equity bridge loan from a consortium of leading international banks.