Superphénix

Superphénix (French pronunciation: [sypɛʁfeniks], English: Superphoenix, SPX) was a nuclear power station prototype on the Rhône river at Creys-Malville in France, close to the border with Switzerland. Superphénix was a 1,242 MWe fast breeder reactor with the twin goals of reprocessing nuclear fuel from France's line of conventional nuclear reactors, while also being an economical generator of power on its own. As of 2024, Superphénix remains the largest breeder reactor ever built. Construction began in 1976, the reactor went critical in 1985 and was connected to the grid in 1986. The project suffered cost overruns, delays and enormous public protests. Overall, the reactor totalized a very low operation factor of 14.4%. Despite many technical issues related to being a first-of-a-kind project most of its downtime was caused by administrative procedure: the plant was technically capable of resuming operations but was forbidden to do so. Technical problems were solved over time and, by 1996, the plant had reached an availability of 95%. The plant was powered down in December 1996 for maintenance, and while it was closed it was subject to court challenges that prevented its restart. In June 1997, the newly appointed Prime Minister, Lionel Jospin, announced that Superphénix would be closed permanently; this was made official by ministerial decree in December 1998.

Power station data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).