Previously, steam turbines have dominated as propulsion machinery for LNG carriers, with their apparent reliability and the ease with which they can burn the boil-off gas from the ship’s cargo tanks while at sea. The low fuel efficiency of steam turbines, however, has encouraged almost all other shipping segments to switch to diesel-powered ships. As a result of both increased fuel efficiency and increased cargo capacity, an LNG carrier with dual-fuel electric machinery will deliver more natural gas to the offloading terminal even when gas is used as fuel throughout the voyage