The technology group Wrtsil reached a new milestone in the battery technology development as the company completed the installation of a hybrid energy system on board Viking Princess. The Norwegian vessel is now the first ever offshore supply vessel in which batteries reduce the number of generators aboard the ship. The new energy storage solution will improve engine efficiency, generate fuel savings and reduce greenhouse gas emissions. Viking Princess completed sea trials and the system was handed over to customer Eidesvik Offshore on 9 October 2017.There is significant potential to save fuel through improved engine efficiency, as the operating profile of supply vessels is highly variable. When using the Wrtsil installed energy storage system on board Viking Princess, the fuel saving potential can be up to 30 percent in various operations and the CO2 emissions can be reduced by up to approximately 13-18 percent 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.