Where was the First Nuclear Power Plant in the World?

The Experimental Breeder Reactor I in Arco, Idaho is the first nuclear reactor to produce electricity.

Where was the First Nuclear Power Plant in the World?

Almost 440 nuclear reactors are operating in the world today. They provide almost ten percent of the world's electricity needs. But where was the first nuclear plant in the world?

The Experimental Breeder Reactor I, or EBR-I, in Arco, Idaho became the first nuclear reactor to produce electricity on December 20, 1951. EBR-1 was opened as a research reactor and led to the construction of future reactors. Russia’s Atomic Power Station 1 Obninsk was the first nuclear power plant connected to the power grid in 1954.

Let’s take a closer look at EBR-I and the effect it had on nuclear power not only in the United States but worldwide as well.

Walter Zinn

EBR-1 was designed and constructed by the American nuclear physicist Walter Zinn, the first director of the Argonne National Library. Walter Zinn worked on the Manhattan Project’s Metallurgical Laboratory during World War II. He supervised the construction of Chicago Pile-1, the world's first nuclear reactor. CP-1 was first operated on December 2, 1942, on the campus of the University of Chicago.

In 1948 Walter Zinn was convinced that they should move the building of large nuclear reactors outside of the Chicago area. At that time the land outside Arco, Idaho was purchased and became the first outpost of Argonne.


Construction began in 1949 on Chicago Pile 4 also known as Zinn’s Infernal Pile. The name would later be changed to Experimental Breeder Reactor I. The reactor installation took place early in 1951. It began operating on August 24, 1951.


On December 20, 1941, energy was captured from EBR-I for the first time. It was able to illuminate four 200-watt light bulbs making it the first energy-generating power plant in the world. On the next day, It was able to produce enough power for the entire building it was housed in. It produced 200kw of energy out of the 1.4mw of heat the reactor generated.

EBR-I was continually able to supply power to its buildings until its decommission in 1964.

The EBR-I's Purpose

EBR-I wasn't designed for electricity production but instead to validate the nuclear physics theories that the breeder reactor was possible. After continuing operation in 1953, it was confirmed the hypothesis that the reactor was indeed producing additional fuel during fission.

Borax Experiments

A series of destructive tests on boiling water reactors were also conducted by the Argonne National Library in Idaho. These were known as Borax Experiments. During the first Borax-1 test conducted under Zinn’s supervision, the control rods were removed to confirm the reactor would shut down without any issues.

The reactor did not shut down and blew up leaving a large column of dark smoke. This was unexpected. When Zinn told Harold Lichtenberg, a nuclear engineer, to replace the rods he said they were already flying through the air.


A nearby experimental boiling water reactor plant, Borax-III was the first power plant that connected to an external city. On July 17, 1955, Borax-III was able to provide 2,000 kW of power to the nearby city of Arco, Idaho as well as the National Reactor Testing Station. That was the first time an entire city was solely powered by nuclear energy.

Borax-III continued to be used for testing until it was decommissioned in 1956.


On November 29, 1955, there was a partial meltdown of the EBR-I reactor during the coolant flow test. This test was attempting to find the source of the unexpected reactor response to a change in the flow of coolant. It was repaired and further experiments determined that the thermal expansion to the fuel rods and thick plates that support the fuel rods were the reason for the reactor response.

This meltdown helped nuclear scientists understand the thermal capacity of the materials that are used in testing. It served as a big contribution to the advancement of nuclear technology.

APS-1 Obninsk

Atomic Power Station 1 Obninsk is located about 68 miles southwest of the Russian capital of Moscow. The construction of APS-1 Obninsk began on January 1, 1951. It was able to become critical on May 6, 1954. A short time later on June 27, 1954, it became the first nuclear power plant that was connected to the grid in the world.

APS-1 was the only nuclear power plant in the Soviet Union until the Siberian Nuclear Power Station was commissioned in 1958. APS-1 was removed from the power grid in 1959 but continued to operate as a research and isotope production plant. It was completely shut down on April 29, 2002.

Interesting Facts

National Landmark and Museum

In 1966, EBR-1 was made a National Historic Landmark.  It now serves as The EBR-1 Atomic Museum. It is open every day of the week between Memorial Day and Labor Day.  It also opens on December 20th of each year to celebrate the anniversary of its first power production.

Music Video

EBR-1 was featured in the music video for the song Clean Power Forever by Eric Meyer. Eric Meyer is the founder and Executive director of Generation Atomic a nonprofit organization that supports the advancement of nuclear energy in the future.

Nuclear Powered Jet Engines

There are two nuclear propulsion jet engines at the EBR-1 building. They were developed as prototypes that are powered by the heat from nuclear fission, enabling them to have extended flight periods.

Lego Figure

In 2019, EBR-1 was in the running to become a Lego playset. The two-story playset featured the EBR-1 reactor as well as the four 200-watt light bulbs it powered in 1951. It, unfortunately, did not gather the support it needed. On January 1, 2021, it was announced that it was no longer eligible to become a Lego playset.


EBR-1 was the first nuclear reactor to produce power. On December 20, 1951, it was able to power 4 200-watt light bulbs. It was only intended to be a research reactor. It contributed to the opening of other nuclear reactors until it was decommissioned in 1964.