Ships

People are often surprised to find out that small nuclear reactors have been powering military vessels since the 1950's and these ships can go 30 years without refueling. There are currently 450 nuclear powered ships including submarines and 11 aircraft carriers. On a submarine the engine is 30 feet in diameter and 40 feet long. These have power of about 200 megwatts. In the future most commercial ships will be nuclear powered. Rolls Royce in England has been building these reactors for 60 years and the company is one of several that are currently building small nuclear reactors for land use. Overall build time is expected to be four years for a 470 MWe plant for a cost of $2 billion dollars.