Sacrificial anodes have what type of potential?

Sacrificial anodes have limited driving potential because they are designed to corrode preferentially in order to protect other metal components, such as those found in underground storage tanks, from corrosion. The anodes create a galvanic cell, and their effectiveness in cathodic protection is dependent on the amount of current they can provide. Once the sacrificial anode has corroded to a certain extent, its ability to provide protection diminishes, leading to the conclusion that the driving potential is indeed limited.

This limited driving potential is critical for operators to understand since it means that the anodes must be monitored and replaced periodically to ensure continued corrosion protection. Hence, while they are valuable in prolonging the life of tanks and piping, there is a finite capacity within which they can function effectively, emphasizing the importance of maintenance in UST systems.