Nuclear-powered icebreaker

A nuclear-powered icebreaker is an icebreaker with an onboard nuclear power plant that produces power for the vessel's propulsion system. Although more expensive to operate, nuclear-powered icebreakers provide a number of advantages over their diesel-powered counterparts, especially along the Northern Sea Route where diesel-powered icebreaker operations are challenging due to the heavy power demand associated with icebreaking, limited refueling infrastructure along the Siberian coast, and the endurance required.

Source: Wikipedia — Nuclear-powered icebreaker (CC BY-SA 4.0)