DNV GL has developed the first type approval scheme for the use of aluminium cables and connectors on board vessels.
The new type approvals for aluminum cables and connectors allow expensive copper to be replaced with aluminum. The cost savings can be significant – with the price of aluminium in 2018, approximately one third that of copper.
More Economical Power Cables
'Traditionally, power cables for marine use have been made with copper,' explains 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.'
Less Weight, Easier Installation
Aluminum’s lower conductivity means that a thicker cable is required, but this is compensated for by an overall lower weight. For example, a typical offshore support vessel may have 60 tons of copper cables installed. If these were replaced with aluminum, the weight would fall to 30 tons. Even with the price of special high quality terminations factored in, the overall estimated savings from switching to aluminum from copper is 50 per cent.
Lighter cables also result in easier installation for the ship builder and lower material transport costs. Finally, a vessel with aluminium rather than copper cables, is lighter and more fuel efficient – resulting in lower operational costs.
Olympic Artemis
The use of aluminium cables has been tested for the past three years in a pilot installation on board 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.
The Olympic Artemis.
Recently, DNV GL experts, together with representatives from the cable manufacturer Amo Specialkabel AB, checked the aluminum 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.
Picture (top): Verifying the conditions of the terminations by thermography (by DNV GL).
