Icephobic PTFE coatings for wind turbines operating in cold climate conditions

A new treatment offers a simple and inexpensive method to reduce considerably ice adhesion on a wind turbine blade surface ensuring a safe and reliable energy production during winter periods. This treatment has icephobic characteristics, satisfactory mechanical, optical and electrical properties and doesn´t alter the surface appearance. The technique consists in depositing a poly(tetrafluoroethylene) or PTFE coating, which strongly clings on a high porosity blade surface. A uniform coating was obtained by dipping the blade samples in a PTFE solution dispersion followed by annealing at 290°C for 2 min in an argon atmosphere. The resulting film yielded a contact angle around 145°, a hysteresis of 30°, a surface tension estimated to 11.7 mN/m and a slipping angle of 45° even at temperature as low as -6°C. The shear strength of ice adhesion was reduced by 80% compared to pristine blade surface at temperatures ranging from -1.8°C to -12.5°C. There was no observed effect of ice shedding events and no accelerated aging was observed through UVC irradiation and corrosive acidic solution on the hydrophobicity of the coated surface. The low surface energy of that coating is promising for its use in the wind turbine industry.