There is significant potential to save fuel through improved engine efficiency, as the operating profile of supply vessels is highly variable. When using the Wärtsilä installed energy storage system on board Viking Princess, the fuel saving potential can be up to 30% in various operations and the CO₂ emissions can be reduced by up to approximately 13–18% per year, depending on operational conditions and requirements.

Furthermore, the hybrid solution will provide a more optimal load on the engines, while the intervals between engine maintenance can be extended.

Viking Princess now runs on a combination of a battery pack for energy storage and three LNG-fueled Wärtsilä engines. The new energy storage solution provides balancing energy to cover the demand peaks, resulting in a more stable load on the engines.

The technology is similar to that used in hybrid vehicles: it prevents the engine load from dipping, and uses the surplus to re-energize the battery, which can be charged as needed. Wärtsilä's remote monitoring and operational advisory services support the daily operation of the vessel ensuring efficient and optimized operations.

The contract to replace one of the four engines on Viking Princess with battery power was signed in May.