From Wikipedia, the free encyclopedia

Experimental Breeder Reactor No. 1
(U.S. National Historic Landmark)
Experimental Breeder Reactor Number 1 in Idaho, the first power reactor. The reactor is in the building at center, the two structures lower left are reactors from the Aircraft Nuclear Propulsion Project
Location:	National Reactor Testing Station
Nearest city:	Arco, Idaho
Designated as NHL:	December 21, 1965
Added to NRHP:	October 15, 1966
NRHP Reference#:	66000307

Experimental Breeder Reactor I (EBR-I) is a decommissioned research reactor and U.S. National Historic Landmark located in the desert about 18 miles (29 km) southeast of Arco, Idaho. At 1:50pm on December 20, 1951 it became the world's first electricity-generating nuclear power plant when it produced sufficient electricity to illuminate four 200-watt light bulbs.^[1][2] It subsequently generated sufficient electricity to power its building, and continued to be used for experimental purposes until it was decommissioned in 1964.

The first production of usable nuclear electricity in Idaho National Laboratory occurred in December 20th, 1951 when four light bulbs were lit with electricity generated from the EBR-1 reactor.

View of EBR-1, as seen from the car park.

As part of the National Reactor Testing Station (now known as the Idaho National Laboratory), EBR-I's construction started in late 1949. The reactor itself was designed by a team led by Walter Zinn at the Argonne National Laboratory. Installation of the reactor at EBR-I took place in early 1951 and the first reaction went critical on August 24, 1951. On December 20 of that year, atomic energy was successfully harvested for the first time. The design purpose of EBR-I was not to produce electricity but instead to validate nuclear physics which suggested that a breeder reactor should be possible. In 1953, experiments revealed the reactor was producing additional fuel during fission, thus confirming the hypothesis. However, on November 29, 1955, the reactor at EBR-I suffered a partial meltdown due to operator error. It was subsequently repaired for further experiments.

Besides generating the world's first electricity from atomic energy, EBR-I was also the world's first breeder reactor and the first to use plutonium fuel. EBR-I was deactivated in 1964 and replaced with a new reactor, EBR-II. Landmark status for EBR-I was granted by President Lyndon Johnson and Glenn T. Seaborg on August 25, 1966. The site has been open to the public since 1976, but is only open between Memorial Day and Labor Day. Also on display at the site are two prototype reactors from the Aircraft Nuclear Propulsion Project of the 1950s.

• Experimental Breeder Reactor I is at coordinates 43°30′44″N 113°00′21″W / 43.512125, -113.005800Coordinates: 43°30′44″N 113°00′21″W / 43.512125, -113.005800