Corrosion of primary substation components and distribution pole in tropical marine atmosphere rich in H2S resulting from the decomposition of sargassum algae

The Guadeloupe Island, located in the Caribbean Sea, is subject to the stranding of sargassum algae, which decompose and release toxic gases, such as hydrogen sulphide and ammonia. These releases of corrosive products, added to the salt climate, represent a risk of accelerated degradation for the components of the electrical network. This study aims to investigate the atmospheric corrosion of Copper, Zinc, Aluminum and Carbon Steel used in primary substation components under these conditions. Four sites, composed of three primary substation and a distribution pole have been equipped with sensors and corrosion indicator coupons near polluted areas. The classification of atmospheric corrosivity has made it possible to identify conditions that vary according to the sites. The corrosion rates recorded on the Bouillante and Capesterre -de-Marie-Galante sites are significant for all the materials considered, with a very high to extreme atmosphéric corrosivity (C5 to CX) according to ISO 9223 standard. The Petit-Bourg and Sainte-Anne sites, further from the coast, have lower but still significant corrosion rates, particularly for zinc and copper with a medium to very high atmosphéric corrosivity (C3 to C5). This atmospheric corrosivity classification can be used for maintenance planning as well as prescriptions on the choice of materials and anti - corrosion coatings.