Enel Green Power has started construction on a 199MW expansion to the 400MW Cimarron Bend wind farm in Clark County, Kansas.
The addition of 74 turbines will increase the capacity of the project to 599MW.
Enel said it is investing $281m (€251m) in the expansion, which is expected to be completed by the end of 2020.
The first two phases of Cimarron Bend entered into service in 2016 and 2017, involving an overall investment of over $891m.
On completion of the third stage overall output at the project will be 2.7 terrawatt-hours a year.
Electricity from a 150MW portion of the expansion is being sold under a 15-year bundled power purchase agreement (PPA) with electric services company Evergy.
The PPA will include support for Evergy’s Renewables Direct program, which allows commercial and industrial customers to offset a percentage of their energy usage through renewable sources.
The Missouri Joint Municipal Electric Utility Commission, which supplies municipal power for more than 60 communities in Missouri and Arkansas, will purchase 30MW of the project under a 12-year bundled PPA.
Electricity and renewable energy credits from the original 400MW portion are sold under bundled, long-term PPAs with Google and the Kansas City Board of Public Utilities.
Enel Green Power chief executive Antonio Cammisecra said: “As one of the largest renewable power producers in North America, Enel Green Power is committed to excellence in not only developing and constructing new projects but also strategically expanding our existing fleet.
“The expansion of Cimarron Bend is a testament to both the maturity of our wind operations and our commitment to growing a portfolio of state-of-the-art renewable plants that will generate value for many years to come, while providing sustainable energy.”
Evergy manager of products and solutions for renewable sources Kevin Brannan said: “As we continue implementing more renewable energy into our overall generation mix, Evergy is pleased to partner with Enel on this expansion project to add to our total wind capacity.
“This helps us reduce carbon emissions and increases our wind energy levels, which leads us toward more sustainable operations and ultimately benefits our customers.”