The savings obviously depend on the condition of the propeller and hull before the work is carried out. Propeller polishing on a well maintained ship will reduce the fuel consumption by 1 – 3%.
Savings are higher in case of hull fouling and in instances of heavy fouling savings as high as 25% on the fuel bill have bean experienced on slow steaming bulkers.
Now, fuel prices are the lowest. Taking into consideration the oil crises of the 70’s, today's market price is about $60 per metric ton in Rotterdam and Singapore. An increase in fuel prices, which is bound to come, will increase the advantages of propeller polishing and hull cleaning.
As the fuel consumption for the ships under review from say 30 ton per day to say 150 ton per day, it is obvious that with a bunker fuel cost around $60 per ton, the savings will range from $18 per day, (30 ton x 1% x $60 per day (150 ton x at $60) - or from $5,400 to $81,000 per year assuming 300 days are spent at sea. All propeller polishing and hull cleaning costs will often be recovered after a few days of steaming rather than months.
Another benefit of a polished propeller is the reduced load on the main engine. This results in less wear and maintenance even when staying within the load limits of the engine.
