The project in central Finland will now comprise 30 turbines, all supplied by Nordex.
The third order will see Nordex manufacturer 11 N131 3MW turbines for the site, taking its combined total to 90MW.
The German manufacturer received the first 13-turbine 39MW order in March 2015. A second phase was added with a further six 3MW turbines ordered from Nordex in July.
Nordex said the first two phases are currently under construction. The third phase is expected to be installed in 2017.
All N131 turbines will be installed on 144-metre towers to put reduce turbulence on the turbine in the mountainous and forested region of Finland.
The turbines will also be equipped to cope with the cold temperatures, Nordex said.