Experimental Breeder Reactor I

nuclear reactor

Also known as: EBR-I

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June 26, 2026

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The Experimental Breeder Reactor I (EBR-I), located in Idaho, was a groundbreaking nuclear reactor. On December 20, 1951, it achieved a historic milestone by generating electricity for the first time from nuclear power, albeit only enough to power four light bulbs.1

A breeder reactor, like EBR-I, is a special type of nuclear reactor designed to produce more fissionable material than it consumes. This capability is crucial for extending the supply of nuclear fuel for electricity generation. Unlike conventional reactors that primarily use uranium-235, breeder reactors can utilize more abundant isotopes like uranium-238 or thorium. EBR-I was developed by scientists at Argonne National Laboratory and was the first experimental breeder reactor. This innovation paved the way for a significant global industry in nuclear energy.231

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breeder reactor
…first experimental breeder reactor, designated EBR-1, was developed in 1951 by U.S. scientists at the National Reactor Testing Station (now called Idaho National Engineering Laboratory), near Idaho Falls, Idaho. France, Great Britain, Japan, and the Soviet Union subsequently built experimental breeders. Although interest in breeder reactors waned after the 1960s…
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…first experimental breeder reactor, designated EBR-1, was developed in 1951 by U.S. scientists at the National Reactor Testing Station (now called Idaho National Engineering Laboratory), near Idaho Falls, Idaho. France, Great Britain, Japan, and the Soviet Union subsequently built experimental breeders. Although interest in breeder reactors waned after the 1960s…
Read More

nuclear reactor
From production reactors to commercial power reactors
…was the Experimental Breeder Reactor, EBR-I, which was designed at Argonne National Laboratory and constructed at what is now the Idaho National Laboratory near Idaho Falls, Idaho. EBR-I was an early experiment to demonstrate breeding, and in 1951 it produced the first electricity from nuclear heat. A much larger experimental…
Read More
…was the Experimental Breeder Reactor, EBR-I, which was designed at Argonne National Laboratory and constructed at what is now the Idaho National Laboratory near Idaho Falls, Idaho. EBR-I was an early experiment to demonstrate breeding, and in 1951 it produced the first electricity from nuclear heat. A much larger experimental…
Read More