Owner and operator of the single-unit facility Nucleolectrica Argentina said the outage was the first since the completion of a life extension project that will see it operate for a second 30-year cycle.
Embalse, a Canada-suppled Candu 6 unit that began commercial operation in 1984, was shut down in December 2015 for the $1bn project aimed at extending the life of the unit and increasing its 648-MW gross capacity to 683 MW through turbine and generator upgrades.
During the recent outage, tasks included inspection of the reactor steam generator, checking the turbine and alternator and partial retubing of the condenser.
Argentina has three commercial nuclear plants – one at Embalse and two at Atucha – providing a share of electricity production of almost 6%.
Argentina is also working on a prototype Carem-25 small modular reactor project, the refurbishment of the Atucha-1 plant, and a used fuel dry storage facility at Atucha.