Dutch netting and rope producer, Van Beelen BV, began this year with a large increase in demand for its Dyneema® D-Netting, thanks to successful trial results from New Zealand customer, Motueka Nets, last year.
The new netting is used to make bottom trawls. According to the results of the trails, fuel costs drop so substantially that Motueka’s clients report to have won back the cost of the net in one trip.
A group of New Zealand twin rigging ships, with engine capacity varying from 3290hp to 4020hp, were first convinced when they fitted one of their ships with fuel flow meters that could accurately measure their diesel usage. Once installed and with the new trawl behind, the gain was evident. Towing the new net they were saving approximately 1 tonne of fuel per day:
A normal trip lasts 42 days. Using the fluctuating fuel prices of 2008 this results in saving around 28,000 to 33,000 Euro per trip. Assuming the boat makes six trips a year, it will save 168,000 to 196,000 Euro a year on fuel costs. Even with the lower fuel prices of the beginning of 2009, huge savings can be made.
During the New Zealand vessels' last trip, more savings were made by installing smaller trawl doors, made possible because Dyneema® D-Netting has less drag in the water and opens without needing as much sideward’s force as trawls made from conventional materials.
The crew on one of the trawlers reported that the new net was so easy to tow and manoeuvre on rough seabed, that less wire and less engine power were needed. This ship had often completely emptied its tank at the end of a trip, but now had enough diesel left to last another 18 days, approximately 216,000 litres. For six trips a year this is about 1.2 million litres of fuel.
A second ship which, just like the others in the group, uses twin rigging in good weather and changes to a single net in heavier conditions, had mainly been using its pelagic net. Since October, however, it has only been using its Dyneema® bottom trawl and stopped twin rigging. The single net is much easier to tow, and catch rates remain the same, but with much less fuel usage.
Smaller ships in the area, between 259 and 550hp, also switched to Van Beelen Dyneema® D-Netting. Without exception they see fuel savings of 30 to 35%.
The skipper of the 550hp Frontier, equipped with fuel flow meters, says: "With our standard 4mm polyethylene net we used 60 litres an hour while fishing. With the 1.5mm Dyneema® net, built precisely the same as the polyethylene net, we used only 45 litres an hour, which means savings of 15 litres an hour."
Crew on all the ships were surprised that, even though they were fishing on rough seabeds, the net showed no wear and tear at all. This is partly due to the coating, especially developed for the new netting.
