Emitted Noise in Harbors - Effect of Shore Power

The presentation will summarize and discuss the noise reduction from ships and offshore rigs in ports, due to the use of shore power. Comparisons of the measured noise reduction with theoretical calculations done in earlier international project will be presented. Noise measurements have been done on both passenger ship and offshore rigs in Kristiansand port, prior to and after connection of shore power. The measurements for passenger ship show marginal reduction of the total A-weighted noise level, but good effect in the lower frequencies. For offshore-rigs noise level on a port building has been continuously registered, prior to and after connection to shore power. These measurements show reductions of the noise level from 12-16 dB, depending on type of rig and the emission level of the rig without shore power.