Energy Storage For Offshore Supply Vessel

Wärtsilä said it has agreed to retrofit an energy storage solution on board a Norwegian ship. The North Sea Giant, a subsea construction vessel, will be fitted with an energy storage system designed to reduce the vessel’s energy consumption, operating costs and exhaust emissions.

The retrofit is responding to requirements of Norwegian North Sea Shipping AS, the owner of the vessel. The solution is designed to provide power redundancy and increases responsiveness of vessel operations.  North Sea Shipping owns, operates and provides management services for advanced offshore supply vessels and is based in Austevoll, Norway.

Typically, a vessel with dynamic positioning uses two or more engines simultaneously to secure back-up power. This means that the engines’ load can run low. By using a hybrid/battery system to provide the needed back-up power, the operational engine can be used closer to its optimal load. In addition to the hybrid/battery solution, the agreement signed in August 2017, includes transformers, filters, switchboard, shore connection equipment, upgrades of existing components and commissioning.

“For us is it important to reduce environmental emissions and modernize the vessel to make it more competitive. In addition, with a more efficient vessel, we will save fuel expenses. The estimated reduction in emissions is 5.5 million kg CO2, 30 tons of NOx and 1200 kg SOx per year. After Wärtsilä had retrofitted our ship Atlantic Guardian in 2014, we really understood how much fuel can be saved by improving the vessel’s efficiency. Efficiency also saves time, because you only need to refuel every second or third port visit,” said CEO Hallvard Klepsvik, North Sea Shipping AS.

The North Sea Giant is a DP3 vessel. The ship is listed in the most advanced category of vessels that apply dynamic positioning. Wärtsilä  claimed installation of an energy storage solution into a class DP3 vessel has not been carried out before and requires a redefinition of applicable classification rules. Reportedly, Wärtsilä and North Sea Shipping AS are working in collaboration with the DNV-GL classification society.