New aluminium-based coating for offshore applications developed by The Advanced Coatings for Offshore Renewable Energy

EU researchers have developed an innovative and environmentally friendly new aluminium-based coating to provide protection for offshore energy installations.
The Advanced Coatings for Offshore Renewable Energy (ACORN) project has developed a new protective coating that will extend the lifetime of marine structures to 20 or more years and avoid the need for supplementary cathodic protection.
The result will be an entirely new, non-paint solution for the protection of offshore renewable energy steel structures including docks, buoys, and oil and gas rigs. Once successful, the coating will boost the competitiveness of the industry and help trigger a widespread roll-out of the different offshore technologies.
The project involved the creation of a highly differentiated and patentable technical solution that could even be extended in the longer term. It uses thermally sprayed aluminium (TSA) – a substance with proven long-term corrosion resistance – to provide a matrix coating with a lifespan of 20 + years.
This porous mix is then dotted with environmentally-friendly active antifouling substances in very tiny concentrations (< 1 %) which will be gradually exposed at the active surface of the coating as the TSA corrodes away at a rate of 10µm per year. Project scientists chose a 99.5 % pure aluminium coating applied with the twin arc spraying method. The eco-friendly anti-fouling substances were then chosen for their performance, commercial availability and regulatory approval for use in EU waters. Scientists also evaluated the inert antifoul carriers for stability in seawater, hydrophobicity and for low processing temperatures to protect the anti-fouling agents. Barnacle resistance tests were then undertaken in marine trials off the coast of Sweden. Now that the project is working on the commercialisation of the new coating, it is hoped that this will make a major contribution to providing environmentally safe solutions as global energy demands and a shift towards renewable energies will likely see the construction of more offshore energy installations over the next decades.