What a Breeder Reactor does

Nuclear reactors utilize fission to produce heat.  That heat is used to raise the temperature of boiling water to produce steam to turn gigantic turbines that produce electricity.  A special kind of reactor is able to serve two functions instead of just making thermal energy.  The use of breeder reactors has declined over the past 60 years.

Breeder reactor

A breeder reactor can produce heat for electricity production and create fuel for other nuclear reactors in the process.  Scientific American explains that one atom of uranium gives off two neutrons during fission.  These neutrons have a lot of energy as compared to the rest of the atom.  A breeder reactor uses these extra neutrons to convert uranium into plutonium.  Plutonium is used for all kinds of applications from medical radiology to nuclear weapons.


The secret to producing energy and other nuclear materials is fission.  Fission is the process by which atoms are split apart.  It takes a lot of energy and the right kind of reaction to do so, but the fission reaction creates a lot of energy in the process.  Fission reactors are responsible for very destructive nuclear bombs.

Breeder reactors and fission

Breeder reactors are able to produce more fissile material than what was originally used in the reactor.  The key is different isotopes of uranium.  Normal reactors need uranium-235 to operate.  However, the only natural isotope of uranium is uranium-238, which is too inefficient for a nuclear reaction.  Breeder reactors are able to take the aforementioned extra neutrons and place them in uranium-238 atoms to produce plutonium-239.  This isotope of plutonium is even more adept at fission than uranium.  A diagram produced by Georgia State University explains the process visually.  

Uses and history

France had a sizeable breeder reactor in the Caspian Sea.  That particular model was used for power generation and desalination.  The United States first used a fast breeder reactor in 1951 at the Idaho National Laboratory.  Designated Experimental Breeder Reactor-1 (EBR-1), the site of the reactor is a National Historic Landmark where visitors can see what early nuclear reactors were like.  The reactor in Idaho was the first such device to produce electricity.

Current status

The International Panel on Fissile Materials has a wonderful piece on the current state of breeder reactors.  There are four major fast breeder reactors in operation among three countries.  Russia has two of them, one of which has been in operation since 1969.  India has another breeder reactor capable of producing 40 megawatts of electricity.  Japan has the fourth, a reactor making 140 megawatts of electricity.  

Breeder reactors may have outlived their usefulness now that nuclear stockpiles are being reduced by the United States and Russia.  Costs and accidents have also led to the spurning of breeder reactors since the 1990s.  However, what a breeder reactor does is important to understand as countries seek alternatives to electrical production as developing nations expand their populations.