US utility Southern Power has expanded its renewable energy portfolio with the acquisition of a controlling interest in a 300 MW solar photovoltaic (PV) facility in California.

Southern, a subsidiary of Southern Company, has purchased the stake in the Desert Stateline facility from First Solar, which will retain the remaining interest in the project.

The venture is Southern’s and First Solar’s fourth shared acquisition, and Southern’s seventh solar acquisition in California.

Desert Stateline will be located on 1685 acres of federally managed public land in San Bernardino County and is expected to consist of approximately 3.2 million of First Solar’s thin-film photovoltaic (PV) solar modules mounted on fixed-tilt tables.

First Solar is building and will operate and maintain the Desert Stateline project. Construction began in October 2014 and will be completed in phases. The plant will be fully operational in the third quarter of 2016.

Southern Power’s renewables portfolio stands at 1450 MW of owned generating capacity, consisting of 20 solar, wind and biomass projects in operation or under development in the USA.