A Bit too Much Salt of the Earth

Abstract

Salty spume, high humidity, stormy winds and driving rain – all of which can result in corrosion, and then there are microbiological attacks as well, with fungi and bacteria. The RAVE project Environmental Influences on Offshore Wind Turbines compared their influences on a turbine in Alpha Ventus with those on the Fino 1 research platform and a near-shore wind turbine on the coast, particularly with regard to the salt deposits on steel, aluminium and fibre composites. Although heavy rain can wash salt off, frequent bombardment with drops of salt also causes devastating corrosion. Two new salt detection systems were successfully tested within the project. Their camera- and laser-aided optics were able to monitor surfaces, for example on the inside of a rotor blade or tower. The high level of humidity in such places encourages the growth of microorganisms, and fibre composites also suffer corrosion damage, meaning that there is also a need for more research in this area.