The ongoing climate changes require ever greater efforts to increase the resilience of the electricity system. In particular, this research aims to reduce the extensive damage caused by intense snow events, mitigating the formation of ice and snow sleeves on overhead current conductors and guard cables. The study presented herein concerns the identification and synthesis of coatings with anti-icing properties to be applied to these components.
Said activity continues the research already conducted in previous years and expands the investigations to further formulations, innovative processes, and characterization methods, with the aim of identifying more effective, environmentally compatible, industrially applicable, and economically sustainable solutions. Non-fluorinated superhydrophobic coatings have been developed for galvanized surfaces, namely elastomeric coatings with different cross-links and elastomeric coatings with a colloidal matrix, in which a liquid additive has been used to increase smoothness between the chains. The synthesized coatings have been characterized chemically and morphologically; in the case of zinc coatings, their resistance to harsh chemical environments (acid, basic, and saline) has been assessed. To assess the icephobic properties, measurements of the nucleation temperature of a drop of water deposited on the coated surfaces and measurements of the adhesion of ice thereto (shear stress test) have been carried out. In particular, alternative methods of shear stress measurement have been developed with compression tests and with a new tool created in laboratories for measurement on flat surfaces. These methods have allowed obtaining more repeatable results and broadening the range of measurable samples. In many cases, the prepared samples have shown excellent anti-icing behavior: adhesion was lower compared to uncoated metal by 5 to more than 50 times.
The results of the field tests collected in the winter of 2020-2021 are presented, where the anti-snow properties of numerous tested coatings are highlighted, but also a certain degradation of the anti-ice properties for the samples exposed for three years. The most promising samples were prepared in large sizes and installed at the Wild experimental station for the winter of 2021-2022. Rings called snowrings were also designed and manufactured with a 3D printer which, combined with anti-ice coatings, mechanically weaken the snow sleeve, promoting its early detachment. The snow rings’ anti-snow properties will be assessed during the next winter. Finally, in continuity with the past year, the study of the physical and mechanical characteristics of the snow has been carried out, with the aim of developing a model of growth of the sleeves which includes the mechanisms that cause their detachment, depending on the adhesion of the snow on the surface and the presence of functional coverings.