Posted June 3, 2020
It stops shellfish and seaweed from growing
ALL SHIPS suffer from fouling: the build-up below the waterline of shellfish, seaweeds and other organisms. This causes drag, which slows the affected craft and increases its fuel consumption. Regular hull cleaning thus makes a considerable difference to the profitability of shipping. It also results in a useful reduction in the amount of planet-warming carbon dioxide emitted by the world’s merchant shipping—an industry that many environmentalists think is notoriously dirty and which could therefore do with burnishing its green credentials.
Roar Ådland, a shipping economist at the Norwegian School of Economics, in Bergen, says that a midsized oil tanker’s fuel consumption (and also, consequently, its emission of carbon dioxide) drops by around 9% after its hull is cleaned at sea—