Punkalaidun In development

Isosuo in numbers

36 - 45 MW

total power


number of turbines


Ilmatar is developing Isosuo wind farm located in the southwestern part of Punkalaidun municipality. The planned areas have predominantly been in peat production use. High-quality wind conditions, distance to residential areas and compatibility with existing land use purposes make especially Isosuo a suitable area for wind power production.

A partial land use plan has been prepared for the Isosuo project and the plan was accepted by the municipality of Punkalaidun in 2015. The plan allows for constructing up to 6 wind turbines with tip heights up to 210m. The environmental impacts of the project have been assessed as part of the land use plan process.

The parallel use of the wind farm areas for example in recreational and berry picking purposes will be allowed also after the wind farm has been commissioned.


The construction schedule of the Isosuo wind farm depends on when the granted building permits become legally valid. Construction can potentially start in 2024, with the commencement of production taking place in 2025.

Ilmatar Service Oy, a subsidiary of Ilmatar Energy, will take over the wind farm’s technical and commercial management once the project has been commissioned.

Ilmatar has been developing the Isosuo and Arkkuinsuo wind farm projects in close collaboration with YIT Rakennys Oy in the past. Ilmatar has since acquired YIT’s share in the project companies and is currently the sole developer.

Ilmatar is progressing the Isosuo wind farm project towards construction phase through its project company, Punkalaitumen Tuulivoima Oy, which is domiciled in Punkalaidun.

The municipality of Punkalaidun declared the enabling master plan of the Isosuo wind power project legally binding on March 9, 2020. The building control committee of Punkalaidun municipality granted the building permits for the planned wind turbines on March 30, 2021. The building permits allow for the construction of six wind turbines with a maximum height of 210 meters. Appeals regarding the building permits are currently being processed by the Supreme Administrative Court, and a decision is expected by the end of 2023. Wind measurements are currently underway at Isosuo, which will enable the final investment decision to be made once the building permits have obtained legal validity.


Further information

Jussi Mäkinen
Ilmatar Energy Oy
+358 40 576 1097
[email protected]