Electricity was cut off in Italy due to an interruption in supply of energy purchased from France subsequent to an outage in Switzerland. In 15 minutes, from the Alps to Sicily, all of Italy was plunged into darkness, except Sardinia. The outage occurred at 3:20 am local time during the night of Saturday to Sunday as Rome was hosting its first all-night cultural event. Four deaths were attributed to this incident:

• a man was killed in a car accident at an intersection with inoperable traffic lights;
• an elderly woman was burned by candles;
• 2 elderly women died from falls in the stairs.

Rome’s metro system had to be evacuated and hundreds of Italians were trapped in elevators. Rail traffic was highly disrupted, as were traffic signal operations.

One of Switzerland’s largest electricity suppliers announced that a wind gust had uprooted a tree, which in turn incapacitated a 380-kV line carrying current into Italy via the Alps around 3 am local time. Yet the company felt that this incident alone could not explain the widespread blackout and accused the overly slow reaction time by the Italian distribution network. The economic impact of these current outages was attenuated by both the time and day, i.e. middle of the night, middle of the weekend. The retailers’ association however estimated that the food processing industry had lost products worth €120 million.

The origin of this failure was in Switzerland, where several very high voltage lines (400,000 V) serving northern Italy were taken offline at 3:01, i.e. 24 minutes before the sudden shutdown of the 2 French lines (i.e. a domino effect). The Minister of Industry asserted that the incident all began from an interruption in the supply of current purchased in France, since at 3:20 am both lines transporting French electricity switched off for an undisclosed reason. Some Italian regions were still deprived of current 2 days after the widespread outage.