[Cherie]

Britain’s electricity grid operator is investigating unexplained power plant failures that hit the UK’s system hours before Spain and Portugal were plunged into blackouts.

Control room staff at the National Energy System Operator (Neso) observed unusual activity on Sunday that saw the power frequency shift unexpectedly in the early morning and the evening.

Keeping the frequency of the electricity system within certain limits is vital to keeping the lights on.

The first event began at around 2am with a power failure at the Keadby 2 gas-fired power plant in Lincolnshire, followed by the unexplained failure of the Viking Link interconnector between the UK and Denmark.

At around 6pm, the frequency shifted unexpectedly again – with the cause currently unknown.

Neso, the quango that manages the British grid, confirmed to The Telegraph on Tuesday morning that officials were investigating.

A spokesman did not provide further details but said there was currently no suggestion that the power failures were linked to each other or the massive system failures that occurred on Monday throughout Spain, Portugal and parts of southern France.

Such investigations are standard practice whenever there is an unexplained power cut on the grid.

The Telegraph