DNV GL approves aluminium cables for ships

DNV GL has developed the first type approval scheme for the use of aluminium cables and connectors on board vessels.

The purpose of aluminium cables and connectors on board vessels is that they allow expensive copper to be replaced with aluminium, reducing costs by as much as 50 per cent as aluminium is approximately one third the price of copper.

Aluminium has a lower conductivity, which requires a thicker cable. However, the increased thickness is compensated by an overall lower weight. A typical offshore support vessel with 60 tons of copper cables installed could be replaced by 30 tons of aluminium. The lighter weight of aluminium cables also means that installation is easier, transport of material is cheaper, and operational costs are lower.

Geir Dugstad, Senior Vice President, Director of Ship Classification & Technical Director at DNV GL – Maritime said: “This type approval represents another first for the DNV GL rule set and demonstrates our commitment to moving classification forward to help our customers. Electrification is playing an increasingly important role in ship propulsion and this new type approval can help to reduce costs and improve sustainability.”

The use of aluminium cables has been tested for the past three years in a pilot installation onboard the Bibby Offshore owned, Olympic offshore managed, Olympic Artemis, a multi-purpose offshore support vessel. The cables have been used to supply power to one of the vessel’s thrusters.

“Traditionally, power cables for marine use have been made with copper,” adds Ivar Bull, DNV GL – Maritime. “Copper is an ideal electrical conductor of course, but the price of copper has been rising sharply over the last several decades – putting increasing cost pressures on the maritime industry. At the same time, electric propulsion is becoming more widespread in shipping, which will increase the demand and importance of finding more economical power cables.”

DNV GL experts, together with representatives from the cable manufacturer Amo Specialkabel AB, checked the aluminium cables onboard Olympic Artemis with a thermographic camera.

The survey confirmed perfect connections after more than 11,000 operating hours and DNV GL was then able to issue the type approvals.