OCTOBER 4, 2012 — Helsinki, Finland, headquartered Eniram Limited has completed an analysis on the effects of hull fouling on cruise vessels in different sea areas.
Eniram, which provides realtime decision support solutions for the shipping industry, undertook a study on 60 cruise ships (90-120,000 GRT) sailing through a variety of sea areas. It says its study is one of the most comprehensive of its kind due to the volume of data collected and high frequency of observations, up to 25 per second.
The sea areas included in the study are the Caribbean, coastal seas round California and Alaska as well as the Mediterranean and the Baltic.
The study also takes into account the impact of washing and drydocking on fouling by using data from over 38,000 operative sea days complemented with temperatures and salinity databases.
The results reveal the high levels of fouling faced by the industry and in particular indicates the considerable differences in fouling build-up between cruising areas, with the Caribbean causing on average the most fouling and the Alaskan area the least.
Eniram created benchmarks for fouling to help ship owners and operators estimate the impact of operating in different areas. This shows that the financial implications of operating in areas with a heavy development of fouling could increase costs close to $500,000 per year on a single cruise vessel.
Data collected to understand the effects of dry and in-water cleaning indicated that even though as a combined figure, the first and the second wash decreased the added power consumption by 2% depending on the coating, fouling continued to increase quite rapidly after the washes, and brushing removed some parts of the coating from the hull. On the other hand, dry dock cleaning had a significant impact on fouling, reducing it by 5%.
In order to ensure the fairest possible results, the sample size of over 60 cruise vessels only took into account vessels that were sailing for a minimum of 30 days in the same area, so as to avoid the interference of possible vegetation from other areas. Furthermore, vessels that were clearly identified as showing unusual fouling results –such as a higher degree of coating erosion– were discarded and excluded from the study.
Henrik Dahl, CTO at Eniram highlighted that "the ability to measure hull fouling build up and its financial consequences stems from Eniram's onshore performance monitoring tools and analysis skills using data obtained from the onboard Eniram data collection platform. With Eniram tools the crew is able to accurately identify at all times all the factors that directly affect a vessel's fuel consumption and performance".
The current study monitored the impact of hull fouling on real fuel savings on cruise vessels. Results have shown that this monitoring helps, customers to distinguish the potential fuel impact of different anti-fouling coating systems sailing in different seas and what impact cleaning strategies have on vessel performance over time. Similar Eniram studies are being planned in the future to bring more concrete examples of the costs of untimely cleaning and study the effects of different in-water cleaning techniques and coating systems to hull fouling.
Download the study HERE