The European Network of Transmission System Operators for Electricity said members across a 25-country area, including Portugal, have taken measures to bring the power grid’s frequency back to 50 Hertz. Spokeswoman Claire Camus said on Tuesday that digital clocks which keep time by the power system’s frequency, such as radio alarms and oven clocks, “are as of today back on time”.
The problem started earlier this year after a dispute between Serbia and Kosovo resulted in energy being diverted from the local grid. That triggered a domino effect across the network that spans the continent from Portugal to Poland and Greece to Germany.