S1G reactor
Encyclopedia
The S1G reactor is a naval reactor
used by the United States Navy
to provide electricity generation
and propulsion
on warship
s. The S1G designation stands for:
This nuclear reactor
was constructed by General Electric as a prototype for the USS Seawolf (SSN-575)
submarine. It was a liquid metal cooled reactor
using pure sodium
to cool the core instead of water, because the higher temperature of liquid sodium (compared to pressurized water) enabled the production of more superheated steam
in the steam generators
. This resulted in a more efficient thermal cycle, yielding more shaft horsepower for a given reactor size. The reactor design had problems because of limited operating temperature
constraints. The major disadvantage of this concept was the ignition of sodium when exposed to air.
S1G was used for testing and training. Eventually a sodium leak resulted in a fire, and the facility was shut down. In the meantime, the S1W
and S2W
pressurized water reactor
s, conceived for the USS Nautilus (SSN-571)
, had demonstrated their superior reliability. The S1G reactor facility and its Horton Sphere were later reused for the D1G
prototype destroyer reactor.
United States Naval reactor
United States Naval reactor refers to nuclear reactors used by the United States Navy aboard certain ships 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...
used by the United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
to provide electricity generation
Electricity generation
Electricity generation is the process of generating electric energy from other forms of energy.The fundamental principles of electricity generation were discovered during the 1820s and early 1830s by the British scientist Michael Faraday...
and propulsion
Nuclear marine propulsion
Nuclear marine propulsion is propulsion of a ship by a nuclear reactor. Naval nuclear propulsion is propulsion that specifically refers to naval warships...
on warship
Warship
A warship is a ship that is built and primarily intended for combat. Warships are usually built in a completely different way from merchant ships. As well as being armed, warships are designed to withstand damage and are usually faster and more maneuvrable than merchant ships...
s. The S1G designation stands for:
- S = SubmarineSubmarineA submarine is a watercraft capable of independent operation below the surface of the water. It differs from a submersible, which has more limited underwater capability...
platform - 1 = First generation coreNuclear reactor coreA nuclear reactor core is the portion of a nuclear reactor containing the nuclear fuel components where the nuclear reactions take place.- Description :...
designed by the contractor - G = General ElectricGeneral ElectricGeneral Electric Company , or GE, is an American multinational conglomerate corporation incorporated in Schenectady, New York and headquartered in Fairfield, Connecticut, United States...
was the contracted designer
This nuclear reactor
Nuclear reactor
A nuclear reactor is a device to initiate and control a sustained nuclear chain reaction. Most commonly they are used for generating electricity and for the propulsion of ships. Usually heat from nuclear fission is passed to a working fluid , which runs through turbines that power either ship's...
was constructed by General Electric as a prototype for the USS Seawolf (SSN-575)
USS Seawolf (SSN-575)
USS Seawolf , a unique submarine, was the third ship of the United States Navy to be named for the seawolf, the second nuclear submarine, and the only U.S. submarine built with a liquid metal cooled nuclear reactor....
submarine. It was a liquid metal cooled reactor
Liquid metal cooled reactor
A liquid metal cooled nuclear reactor, liquid metal fast reactor or LMFR is an advanced type of nuclear reactor where the primary coolant is a liquid metal. Liquid metal cooled reactors were first adapted for nuclear submarine use but have also been extensively studied for power generation...
using pure sodium
Sodium
Sodium is a chemical element with the symbol Na and atomic number 11. It is a soft, silvery-white, highly reactive metal and is a member of the alkali metals; its only stable isotope is 23Na. It is an abundant element that exists in numerous minerals, most commonly as sodium chloride...
to cool the core instead of water, because the higher temperature of liquid sodium (compared to pressurized water) enabled the production of more superheated steam
Steam
Steam is the technical term for water vapor, the gaseous phase of water, which is formed when water boils. In common language it is often used to refer to the visible mist of water droplets formed as this water vapor condenses in the presence of cooler air...
in the steam generators
Steam generator (nuclear power)
Steam generators are heat exchangers used to convert water into steam from heat produced in a nuclear reactor core. They are used in pressurized water reactors between the primary and secondary coolant loops....
. This resulted in a more efficient thermal cycle, yielding more shaft horsepower for a given reactor size. The reactor design had problems because of limited operating temperature
Operating temperature
An operating temperature is the temperature at which an electrical or mechanical device operates. The device will operate effectively within a specified temperature range which varies based on the device function and application context, and ranges from the minimum operating temperature to the...
constraints. The major disadvantage of this concept was the ignition of sodium when exposed to air.
S1G was used for testing and training. Eventually a sodium leak resulted in a fire, and the facility was shut down. In the meantime, the S1W
S1W reactor
The S1W reactor was the first prototype naval reactor used by the United States Navy to prove that the technology could be used for electricity generation and propulsion on submarines...
and S2W
S2W reactor
The S2W reactor is a naval reactor used by the United States Navy to provide electricity generation and propulsion on warships. The S2W designation stands for:* S = Submarine platform* 2 = Second generation core designed by the contractor...
pressurized water reactor
Pressurized water reactor
Pressurized water reactors constitute a large majority of all western nuclear power plants and are one of three types of light water reactor , the other types being boiling water reactors and supercritical water reactors...
s, conceived for the USS Nautilus (SSN-571)
USS Nautilus (SSN-571)
USS Nautilus is the world's first operational nuclear-powered submarine. She was the first vessel to complete a submerged transit beneath the North Pole on August 3, 1958...
, had demonstrated their superior reliability. The S1G reactor facility and its Horton Sphere were later reused for the D1G
D1G reactor
The D1G reactor was a prototype naval reactor designed for the United States Navy to provide electricity generation and propulsion on warships. The D1G designation stands for:* D = Destroyer platform* 1 = First generation core designed by the contractor...
prototype destroyer reactor.