The approval comes on the heels of President Barack Obama's unveiling of his plan to reduce US carbon emissions, which includes having the DOI approve another 10GW of renewable energy projects on public lands by 2020.
The DOI said there are another 14 active renewable energy proposals slated for review this year.
Although the project has the green light, it is not clear when construction will begin. BP, which has put its US wind business up for sale, did not immediately respond to a request for that information.
The proposed project calls for the installation of up to 243 wind turbines on 38,000 acres of federal land.
The company agreed to undertake significant mitigation efforts to minimize impacts to wildlife, including reducing the project's footprint by 19% from the original proposal.
A smaller footprint will protect golden eagle habitat and reduce visual and noise impacts to the Lake Mead National Recreational Area, the department says.