The loan is to German turbine manufacturer Enercon, which is building the project and supplying the turbines in central Uruguay. Peralta will comprise 50 Enercon E-92 2.35MW turbines.
The project has a 20-year power purchase agreement with state utility UTE.
The loan will be paid in three parts and includes a partial federal export credit guarantee, KfW said.
"German and European wind technology is in demand internationally. This is a great opportunity both for manufacturers and the environment. As a bank, we do our part in helping ideas and projects take concrete shape," said KfW board member Markus Scheer.
The German lender said Uruguay was targeting 38% of its electricity production to be from wind by 2017, up from 13% a year ago.