The deal amount has not been disclosed but the company said that the deal is planned to be completed in late 2015 upon completion of the project.

Southern Company chairman, president and CEO Thomas Fanning said: "Through the acquisition of the Kay Wind project – the Southern Company system’s first wind facility and largest renewable energy project to date – we are further diversifying our generation portfolio by expanding to a region with abundant wind resources."

Apex Clean Energy is responsible for the development, operation and maintenance of the facility while Blattner Energy will serve as the engineering, procurement and construction contractor.

Located in Kay County, Oklahoma, the project features Siemens Energy-manufactured 130 wind turbines and will be capable of generating enough electricity required to power approximately 100,000 homes in the US.

The wind farm’s electricity and associated renewable energy credits (RECs) generated will be sold Westar Energy and Grand River Dam Authority (GRDA) in Oklahoma under 20-year power purchase agreements.