With the approaching end of the productive lives of offshore oil and gas platforms, the issue about decommissioning and what to do with existing structures arises. In this regard, this study aims to test solutions, at a preliminary level, for the eco-sustainable reuse of platforms at the end of their extraction phase. In particular, mineral accretion technology is applied by low-voltage electrolysis of seawater due to the precipitation of calcium carbonate on a cathode material in order to assess the protection capacity of the platforms against corrosion. This approach allows the extension of a platform’s “life” under a more sustainable purpose. The results, derived from laboratory and field experiments, will allow us to reduce uncertainties and define the best operating conditions to increase the efficiency of the mineral accretion technology in the marine ecosystem. The data collection on the main parameters that influence the process (i.e., temperature, salinity, and applied current) and the quantitative analysis of the collected material allowed us to acquire a better knowledge about mineral composition and deposition rate.