The Orosi wind farm in the province of Guanacaste will feature G87 2MW turbines made at Gamesa's Pennsylvania factory.
Ex-Im signed off a $61.1 million direct loan to the developer Inversiones Eolicas de Orosi Dos, a subsidiary of the Central American wind company Globeleq Mesoamerica Energy.
The bank said it agreed the loan in order to support American jobs at Pennsylvania factory, which has already seen several rounds of job cuts, with hundreds of positions lost.
David Flitterman, chairman of Gamesa North America said: "The bank has facilitated a number of export projects for Gamesa, including the Orosi project, and continues to work with us to create new opportunities for growth and expansion."