Cathodic protection (CP) in closed compartments is commonly achieved by the use of sacrificial anodes. Either aluminum or zinc is used and today’s standards do not discriminate the one from the other.
One of the internal corrosion protection strategies for monopiles used in the offshore wind industry is CP using sacrificial anodes. In that context testing has been carried out to study the CP design parameters and any effect sacrificial anodes have on the water chemistry – especially pH. This paper gives results from testing with AlZnIn and Zn anodes, and discusses important design parameters such as anode capacity and design current densities. In addition and most importantly pH variation with time for the two anode materials is given and is further discussed with respect to current density and capacity.