A nationwide power cut on Tuesday happened when every plant at the Delimara power station tripped due to a severe voltage dip caused by the interconnector being suddenly shut down, Enemalta has said.

Power was shut down across Malta and Gozo for several hours on Tuesday afternoon, just as the country was in the midst of political turmoil.

An Enemalta spokesman had at the time attributed the shutdown to a fault at the Sicily side of the undersea interconnector.

On Wednesday, the company provided a fuller timeline of events that caused the power cut.

Enemalta said a fault at a Ragusa substation at 2.39pm caused the interconnector to be automatically shut down by a safety system designed to safeguard equipment. 

Simultaneously, all the generation plants at the Delimara Power Station tripped due to the severe voltage dip caused by the Ragusa fault. 

The first emergency gas turbine generator kicked in at 3.10pm and by 3.24pm the interconnector was re-energised from Ragusa. Four minutes later, the first Magħtab Terminal Station transformer was energised, the company said.

At 3.46pm the 33kV network from Delimara power station was energised, and at 3.51pm supply started to be restored to the Ħal Far and Freeport areas from the Delimara power station.

Within roughly 30 minutes - 4.23pm - Enemalta’s 132kV busbars at Magħtab were energised through the interconnector and within 11 minutes the network was energised.

At 4.58pm, Delimara Power Station was synchronised with the interconnector and by 5.49pm the electricity supply to most areas in Malta and Gozo was restored.

By 6.52pm, supply to all areas was restored, following site interventions by Enemalta personnel.

The company thanked its team of 50 engineers and technicians who worked tirelessly to restore the service in the shortest possible time.

It said it appointed an internal enquiry to establish all the facts and recommend corrective actions. The timeline provided, it said, was still subject to the inquiry.