"Although Riffgat is feeding into the power grid only since the spring, the 140 million kilowatt hours delivered meet the annual electricity needs of 40,000 homes – that's clearly above our expectations," says Irina Lucke, head of offshore services and solutions at EWE, and project manager for Riffgat.

EWE couldn't specify exactly what its expectations for Riffgat's power output had been, but measurements elsewhere have also pointed to a higher electricity production in offshore wind in the North Sea than expected.

Germany's