Sata Shipbuilding Oy, the shipyard of which has been supplying demanding steel structures around the world for more than 50 years, operates near the Pori Offshore Wind Hub in Mäntyluoto.
Together with the Helsinki shipyard, Sata Shipbuilding forms Davie Group’s Finnish operations. Canadian Davie Shipbuilding acquired Enersense Offshore Oy from Enersense Plc in July 2025. The company invests in Mäntyluoto and builds an even stronger maritime industry competence hub in the area, which manufactures both marine industry structures and packages as well as demanding offshore solutions.
In addition to steel structures equipped on icebreakers, the company’s key products include offshore wind turbine foundation solutions. Offshore wind turbine foundations and substructures are a critical part of a functioning and sustainable wind farm. The substructures are built completely underwater, which means that the technical requirements are high.
“The substructures are very large and they are in seawater exposed to weather. Their structures and surface treatments must be designed and made to last,” says Niko Suomela, Managing Director of Sata Shipbuilding.
Expertise is valued worldwide
The Mäntyluoto shipyard was originally founded by Rauma-Repola, and over the decades it has delivered a large number of both fixed and floating foundations across the world. The shipyard delivered the world’s first floating offshore wind turbine foundation to a Norwegian wind power company and it has delivered two-thirds of the world’s SPAR oil rig structures. They are all still in use and can withstand harsh conditions, ranging from the high salt content of the oceans to exceptional conditions like hurricanes.
“The Mäntyluoto shipyard is probably better known across the world than in Finland. The largest structures delivered by us have been hundreds of metres long and weighed almost 30,000 tonnes. Going forward, we will further strengthen the shipyard’s expertise and capacity,” Suomela says.
Substructures according to customer wishes
The Mäntyluoto shipyard has also supplied the substructures for the world’s first wind farm to be built for freezing sea conditions by Suomen Hyötytuuli in Tahkoluoto, Pori.
Gravity foundations were delivered to Tahkoluoto, which were best suited to the sea location and depth in question. The conical design of the substructure lifts the ice up and ensures durability even in harsh winter conditions.
Sata Shipbuilding has also patented its proprietary floating substructure solution that does not require a dedicated vessel for installation, but can be pulled to the installation site by a tug. The company also manufactures multi-pillar cross-structures, which have been delivered to wind farms on the east coast of the United States, for instance. At the end of last year, the shipyard started hull production for the heavy Polar Max icebreaker ordered by the Canadian Coast Guard from Davie.
Suomela emphasises the shipyard’s customer-oriented operating model.
“There are various solutions, but it is essential to always choose the one that best suits the customer’s project. It all starts with the customer’s wishes and the turbine supplier chosen by the customer. For offshore wind, the size of the turbine and the foundation of the installation area affect the dimensioning of the substructure. We listen to our customers’ wishes with a keen ear.”
Offshore wind farm synergies are obvious
The substructures of offshore wind turbines are massive structures, but since each is adapted to its own position, the substructures are different from one another. It is also essential to design the substructures for the prevailing conditions – for example, the salt content in the Bothnian Sea is lower than in the oceans, which affects protection against corrosion. The design always starts with the customer’s needs and requirements.
According to Suomela, the Pori Offshore Wind Farm is a great project and exactly what the area needs. All relevant suppliers are involved.
“Synergy is a matter of course. When I look through the office window, I can see all the key parties and the Tahkoluoto wind farm. Here, we have everything we need to produce world-class solutions.”