Tag Archives: EBR-1

EBR-1 light bulb

Atomic Snapshot: EBR-1 Light Bulbs

EBR-1 light bulb
One of the four original light bulbs lit by nuclear power on December 20, 1951.

At 1:50 PM on December 20, 1951, about 18 miles southeast of Arco, Idaho, four 200-watt light bulbs were illuminated by the world’s first breeder reactor as an experiment as an electricity-generating nuclear power plant. The Experimental Breeder Reactor (EBR-1) was the first time that a reactor created in-house available electricity.

The next day, December 21, 1951, the reactor produced enough electricity to power the building and the parking lot.

The world’s first electricity produced by a nuclear reactor occured in September, 1948, at the X-10 Graphite Reactor in Oak Ridge, Tennessee. A small steam turbine connected to the reactor lighted a single light bulb.

Later in 1955, the BORAX-III experimental boiling water reactor, also in Idaho, was connected to external loads which powered Arco, the first time a city was powered solely by nuclear power.

Arco Community Center

On December 21, 1951, the male “project” EBR-1 staff members chalked their names on the wall. In 1995, the female “support” personnel’s names were added on a plaque to the right of the signed names.

The EBR-1 staff members chalked their names on the wall.

You can visit EBR-1 which is set up as a self-guided museum from Memorial Day to Labor Day. During Arco’s Atomic Days celebration (3rd weekend in July), past INL employees provide guided tours.

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EBR-1 near Arco, Idaho
Experimental Breeder Reactor 1 (EBR-1) outside Arco, Idaho.

This month’s calendar features the Experimental Breeder Reactor I (EBR-1) which is just a short drive from Arco, Idaho, across from the Idaho National Laboratories.

EBR-I began power operation on August 24, 1951, and was decomissioned in 1964. It was dedicated as a Registered National Historic Landmark on August 25, 1966, by President Lyndon Johnson and Glenn Seaborg, chairman of the Atomic Energy Commission. On June 4, 2004, the Institute of Electrical and Electronics Engineers (IEEE) dedicated the facility as a Milestone in Electrical Engineering and Computing.

EBR-1 was the first operating breeder reactor, which produces more fuel for the fission process than it consumes. The breeding process involved converting uranium-238 into plutonium via fast neutrons. This then heated a liquid metal (sodium-potassium alloy) through a heat exchanger for coolant, in turn heating water into steam for turbine electrical generation.

The reactor was completed in 1951, and on December 20, 1951, it became the world’s first nuclear power plant, generating enough electricity to power four 200-watt light bulbs.

EBR-1 generator
EBR-1 Generator with replicas of the four 200-watt light bulbs.
EBR-1 light bulb
One of the four original light bulbs lit by nuclear power on December 20, 1951.

EBR-1 is a museum in which visitors can wander throughout the building on a self-guided tour (May through September) to see various exhibits and information about the breeder reactor. These two exhibits note that on December 21, 1951, all of the electrical power in the building was supplied by atomic energy.

Be sure to download this month’s calendar featuring significant atomic events from 1933 to 1994 as well as 80 atomic shots conducted during September since 1945, including the last nuclear shot on September 23, 1992 (Julin: Divider).

SmarterEveryDay @ EBR-1

Destin Sandlin of the Smarter Every Day YouTube channel recently visited the EBR-1 outside Arco, Idaho. As Atomic Tourists, we wanted to share his video.

Destin goes on a tour of the Experimental Breeder Reactor (EBR-1) with the Idaho National Laboratories. In addition, as an engineer and science communicator, he provides a great explanation of nuclear power and specifically a breeder reactor.

As a reminder, the EBR-1 is a National Historic Landmark where usable electricity was first generated in 1951. The facility is open to the public from Memorial Day weekend through Labor Day, every day from 9am to 5pm, for self-guided tours. Usually, during Atomic Days in Arco (third weekend in July), INL volunteers are are on hand to answer questions and provide guided tours.

Self-guided tour brochure: