Storm Arwen

The milestone follows eight months of work to clear the damage of November's Storm Arwen, which uprooted more than one million trees in Northumberland.

Energy regulator, Ofgem, said it is completely unacceptable that 4,000 customers were without power for a week and almost all received an unacceptable service.

The regulator singled out Northern Powergrid as having the "worst" response to Storm Arwen after its findings were published into what went wrong.