A Swiss nuclear reactor - the world's oldest - has been switched off for cable repairs, says the Alpine nation's nuclear authority. Beznau 2 lies near Germany and draws cooling water from a Rhine River tributary.
An oil leak in a cable duct in a "non-nuclear part" of Beznau's reactor had prompted the Friday night shutdown, said the Swiss Federal Nuclear Safety Inspectorate (ENSI).
AXPO, the firm that operates Switzerland's Beznau at Döttigen, near the German border town of Waldshut, said repairs would take some days. ENSI said once checked, the reactor would be restarted.
Oldest in the world
Beznau 2, commissioned in 1971, ranks as the world's oldest, nominally functioning reactor since the closure of Oldbury, near Bristol in Britain, in 2012. That site, however, is earmarked for new reactors by a consortium.
Beznau's other reactor, number 1, dating from 1969, has been down since March 2015. Both plants source cooling water from the Aare, a Swiss tributary of the Rhine, which flows through Germany and the Netherlands.
Beznau's pause leaves Switzerland with four active nuclear plants, with the nation 60-percent- dependent on nonfossil sources, notably hydroelectric power.
In a May referendum, the Swiss endorsed energy legislation focused on renewables that would forbid the building of new atomic plants. Existing nuclear power generators would, however, run as long as they are officially deemed safe.
Another Swiss plant, Mühlenberg, near Bern, was throttled by 5 percent in June, because cooling water from the Aare had climbed to 20.5 degrees Celsius (69 degrees Fahrenheit).
Protests against Belgian reactors
In June, thousands of people formed a human chain across the border triangle that spans western Germany, Belgium and the Netherlands to demand that Belgian operators shut down the Tihange 2 and Doel 3 reactors over safety concerns.
Protests also linger over Fessenheim, near Germany's southwestern border and one of 58 reactors operated by France.
In April, France's previous government decreed that Fessenheim would stop production by April 2020.
France is building a replacement plant at Flamanville near the Atlantic port of Cherbourg.