Sacrificial Anodes

Zinc and aluminium are generally used in salt water, where the resistivity is generally lower. Typical uses are for the hulls of ships and boats, offshore pipelines and production platforms, in salt-water-cooled marine engines, on small boat propellers and rudders, and for the internal surface of storage tanks.

The advantage of sacrificial anode systems over others are they need no external power source, are easy to install, the low voltage and current between the anode and the surface it is protecting infrequently generates stray current, overprotection is unlikely, and inspection and monitoring is simple