The Koraal Tabak wind farm on the Dutch Caribbean island of Curacao is nearing completion. The last of the five Vestas V150 turbines has recently been erected. Windbase was responsible for the foundation design. During the construction phase, Windbase provided expert guidance on the foundations and steel components of the wind turbines.

The foundation design presented some challenges due to the soil conditions at the construction site. As the name suggests, Koraal Tabak is situated in close proximity to the coastline, where the soil composition is predominantly coral limestone. The nature of this type of stone is such that, over time, it may develop cavities, which can make foundation work more challenging. In general, the top soil layers are more solid and hard, while the lower soil layers, which are more affected by groundwater and seawater, are less hard and have more cavities. The results of the local soil investigations highlighted the presence of unfavorable soil layers and cavities, necessitating a minor repositioning of the turbines. Ultimately, the optimal solution in terms of optimization and risk mitigation was to utilize shallow foundations with a founding depth of only 0.5 m.

Main foundation parameters per foundation:

Concrete C30/37: 739 m3

Concrete C45/55: 17 m3

Reinforcement B500B: 63 tons (83 kg/m3)

Foundation diameter: 23 m

Four in a Row!

The Windpark Koraal Tabak project represents the fourth undertaking on the island for Windbase, where the company has assumed responsibility for foundation design and QA/QC throughout the execution phase.

Following a comprehensive preparation phase, construction commenced last spring. The Windpark Koraal Tabak project was successfully completed within just six months. As Windbase’s involvement extends beyond the delivery of design documents, we were also actively engaged during the preparation phase, sharing our expertise and providing advice to local parties.

We held numerous discussions and meeting with our project partners on Curaçao, where we used Teams to share our design concepts, tips, and tricks. During the foundation execution, Windbase fulfilled the role of the client’s advisor, ensuring QA/QC through activities such as rebar inspections and oversight during the concrete pouring process.

We are pleased to announce the successful installation of all five turbines, with the park expected to be fully connected to the grid by the end of the year. This will add another 20 MW of wind energy capacity to the Curaçao grid.

We would like to congratulate all project partners on the successful completion of this amazing project. We look back on this collaboration with pride and satisfaction. We now look forward to our next international adventure!