Aerospace technology could help develop a new protection system for offshore wind turbine blades that could eliminate the need for intervention related to rain erosion, a new research suggests.
Conducted by the Offshore Renewable Energy (ORE) Catapult, Doncasters Bramah and Performance Engineered Solutions (PES), the Leading Edge for Turbines (LEFT) project suggests that the by stopping the need for intervention lighter turbine blades and drivetrains could be a reality.
The two-year project focuses on studying and validating an optimal method of attaching such a solution to offshore wind blades, in addition to considering how to integrate the design of a nickel-cobalt leading edge into the overall design and functionality of blades.
The partners suggest the electroforming fabrication process in which parts are grown in a chemical bath onto a preformed mandrel to produce near net shape parts, removing the need for multi-stage forming operations associated with conventional metal forming techniques.
The parts are electroformed in a nickel-cobalt alloy, which has a high tensile and yield strength, and a high hardness value compared to titanium and stainless steel, which is said to make it ideal for producing lightweight erosion shields.
Benchmark rain erosion testing at ORE Catapult has indicated that the nickel-cobalt solution could be expected to give 30 years protection when continuously tested to offshore wind specifications.
“The nickel cobalt alloy has the best rain erosion performance of all products tested in ORE Catapult’s rain erosion test rig. Not only does it have an outstanding erosion lifetime, it is also resistant to different test conditions unlike other products tested," said Kirsten Dyer, Senior Research Engineer, Materials at ORE Catapult.
According to project partners, such an advance in erosion performance would not only lead to the introduction of larger, lighter blades but also to reduced turbine nacelle sizes through smaller subsystems.
Turbine operators are also expected to see benefits through reduced repair costs, estimated to save around GBP 1.3m per turbine during a typical 25-year service life.
The GBP 1 million project will also investigate opportunities for recycling, refurbishment, reuse and end of life disposal for all materials and chemicals used within the electroforming process to reduce waste further.