Two-year sea trial confirms Selektope’s antifouling efficacy

Two-year sea trial confirms Selektope’s antifouling efficacy

Selektope, the organic, non-metal antifouling ingredient developed by Swedish company I-Tech, has proven its ability to prevent barnacle fouling on ships over an extended operational period.

Selektope was applied to the vertical and flat bottom of Laurin Maritime’s 46,000 DWT chemical and oil tanker, Calypso, in 2015. The vessel then spent 24 months in active operation, across a variety of trade routes, and more than 50% of this time spent in biofouling hotspots with temperatures between 25° and 32°C, where biofouling is exacerbated.

Hull and propeller analysis was carried out, showing Calypso’s total increased resistance to be 7% after the 24-month operational period. Comparing this with a benchmark, a resistance of 10-20% would be expected. Over the period, speed losses amounted to 2% when measured against sea trial performance. The performance analysis also revealed that the added resistance for Calypso amounted to 0.1%. Between 0.5 and 1.5% is typical for the time period and operating conditions.

An underwater hull inspection by divers also demonstrated a very clean hull from Calypso, with no soft or hard fouling over the starboard and portside verticals, flat bottom, and bilge areas. Laurin Maritime’s technical director Bertil Andersson confirms: “The vessel has now operated for two years since last dry dock, and we can conclude that the fouling of the hull (read added hull resistance) remains at a very low level and the trend continues being flat.”

Selektope works by temporarily stimulating the barnacle larvae’s octopamine receptor. This ensures that the larvae are kept in swimming mode and cannot therefore attach themselves to the surface of the ship. The neurological effects are temporary and larvae are able to return to their normal functional capacity shortly after encountering Selektope. According to T-Tech, Selektope has a very high efficacy at extremely low concentrations (0.1% w/w), is ultra-low leaching and offers paint manufacturers the flexibility to boost copper-based paint formulations or replace copper completely with the ingredient.

I-Tech CEO Philip Chaabane says: “This independent analysis of performance data and the underwater hull inspection provide convincing long-term performance results from a full-vessel application of a Selektope-containing hull coating for a vessel with significant exposure to severe fouling conditions. The fact that the hull fouling trend continues to be flat means that our general outlook on the continuous performance of the Selektope-containing coating is very positive. This delivers the proof required that our unique antifouling ingredient can offer ship operators guaranteed hard fouling prevention performance for any vessel activity and trading patterns.”

Images: Above – Laurin Maritime’s Calypso