The high wind-power peak poses a significant challenge to the high-voltage grid and leads to transport bottlenecks, warned TenneT, which caters for wind energy installations in the North Sea and windy northern Germany.

The TSO said it has prepared comprehensive measures to keep the high-voltage grid stable under the expected extreme strain.

"The scope of the planned preventative measures shows how critical the grid situation is," says Urban Keussen, chairman of TenneT.

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