The $915 million project will enter commercial operation by 31 October. Developed by Invenergy, it is the largest wind project in Colorado.
Once online, the project will be operated by Xcel, a utility holding company based in Minneapolis.
The power will be sold to Public Service Company of Colorado, a subsidiary of Xcel.
The two phases — the 400MW Rush Creek I and 200MW Rush Creek II — together consist of 300 x Vestas V100-2MW turbines.
Rush Creek will save residents and business customers an estimated $400 million-plus on a net present value basis over the life of the 25-year project, according to the University of Colorado.
In June, Xcel filed a plan with regulators to add an extra 1.1GW of wind projects in Colorado by 2026, not including Rush Creek, while retiring two coal-fired plants.