Wind energy has become the dominant renewable energy source in Australia with over 77 wind farms currently operating, totaling in excess of 4000 MW of capacity, and more to be installed. Many of these farms are situated near coastal environments and at altitudes that are constantly saturated. This wet environment often causes corrosion issues with the foundation bolts, posing a significant risk to the tower's integrity. Foundation bolts are the only component of the system that cannot be changed out over the life of a wind tower, so their integrity limits the safe operating life of the wind turbine.
A major wind farm operator discovered alarming levels of corrosion of foundation bolting, located just below the concrete to flange interface of a tower's base. This corrosion of threaded bolts set in concrete, grout, or similar substances reduces their effective cross-sectional area reducing bolt strength and consequently component integrity.