ZOE

nuclear reactor

Also known as: EL-1

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July 15, 2026

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ZOE, also known as EL-1, was the first French nuclear reactor, built in Châtillon, near Paris, and went critical in 1948. It was a low-power reactor, producing 150 kilowatts of thermal energy. ZOE used non-enriched uranium as fuel and was a heavy-water-moderated reactor. This type of reactor design was developed in Canada with the ZEEP (Zero-Energy Experimental Pile) reactor, which was also a heavy-water-moderated, natural uranium-fueled research reactor.1

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Frédéric and Irène Joliot-Curie
15, 1948, of ZOE (zéro, oxyde d’uranium, eau lourde), the first French nuclear reactor, which, though only moderately powerful, marked the end of the Anglo-Saxon monopoly. In April 1950, however, during the climax of the cold war and anticommunism, Prime Minister Georges Bidault removed him without explanation from…
Read More
15, 1948, of ZOE (zéro, oxyde d’uranium, eau lourde), the first French nuclear reactor, which, though only moderately powerful, marked the end of the Anglo-Saxon monopoly. In April 1950, however, during the climax of the cold war and anticommunism, Prime Minister Georges Bidault removed him without explanation from…
Read More