Ship propulsion is done by a system, which greatly affects the speed and power of a ship. The major expectations of these power plants were: Reduction of the weight of the propulsion plants in order to free up tonnage for other items. The type of propulsion system used depends on the ship's type and function. There are different types of propulsion system used on ships today. Savannah was a demonstration project for the potential use of nuclear energy. She was built in the late 1950s at a cost of $46.9 million (including a $28.3 million nuclear reactor and fuel core) and launched on July 21, 1959.She was funded by United States government agencies. Steam generation in a conventional steam plant begins with the boiler. United States naval reactors are nuclear reactors used by the United States Navy aboard certain ships to generate the steam used to produce power for propulsion, electric power, catapulting airplanes in aircraft carriers, and a few more minor uses.Such naval nuclear reactors have a complete power plant associated with them. The electric plant provided power to all the ship's services such as weaponry, steering, lighting, cranes, fans, gyros etc. It had a total output of 7,910 kw at 220 volts, with eight 500 kw Diesel generators, five 690 kw turbo-generators, and one 460 kw turbo-generator.

However they have also been used as the main engine in the royal naval warships and the merchant fleets since the mid forties. F. M. Bennett, The Steam Navy of the United States: A History of the Growth of the Steam Vessel of War in the U.S. Navy, and of the Naval Engineer Corps. Both nuclear and conventional plants use steam turbine powered turbine generators for ship's service electrical power. Neither nuclear nor conventional plants develop more power based on the nature of the energy source. The gas turbine normally is used to produce the thrust to power jet aircraft and as generator drives in power stations. The D-type boiler has been installed in US Navy ships since 1950. The introduction of the high-pressure superheated steam boilers took place in connection with the first new ship builds by the Reichsmarine after WW 1. Nuclear powered vessels, whether a ship or submarine, receive its propulsion energy from nuclear power plants that sit onboard. Ship's Power The first ships were fitted with two 400 kW turbo-generators (i.e. (W. T. Nicholson Press, 1896): (reprinted: Westport, CT: Greenwood Press, Pubs., 1972). NS Savannah was the first nuclear-powered merchant ship. By Gina Nichols, Supervisory Archivist/Head of Collections Dept., U.S. Navy Seabee Museum As the Navy transitioned from wooden sailing vessels to a steam powered fleet, three major innovations – steam power, marine railways, and the shiphouse – changed the tone and development of shipyards during the 19 th century. They were popular for a time with the merchant fleet, driving large oil tankers, container ships, and cruise liners. Through the process of heating water to produce steam and ultimately power steam turbines and turbo generators, the ship generates energy. Smaller space requirement Electrical Power Plant. steam generators), one each in the boiler (port after end) and engine (starboard forward end) rooms; and three 200 kW diesel generators - one in the boiler room, the other two on No.3 deck aft and No.4 deck forward. In warships, and in all nuclear plants, there are diesel (or, rarely, gas turbine) back up generators to power critical circuits. [1] Both images from this source. The steam that goes to the main engines, ship's service turbine generators, boiler internal desuperheater and main feed pumps (on certain ships) is called main steam. It is for this reason that the article describes the main types of propulsion systems a ship can use according to its capacity.