Riffgat beats power forecasts

The 108MW Riffgat offshore wind farm in the German North Sea has generated more energy than expected since its delayed commissioning on February 13, its operator EWE said.

"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 pioneering 60MW Alpha Ventus offshore wind farm has produced around 10% more electricity than expected each year between 2011 and 2013, its operators said earlier this year.

Riffgat consists of 30 Siemens 3.6MW wind turbines, erected in water depth of 18 to 23 metres up to a year ago.

The wind park was grid-connected only in February due to delays caused by the clearance of World War 2 munitions in the way of the cables linking the park to land the added €100m to the overall construction costs.

EWE owns 90% of Riffgat, with project developer Enova holding the remainder. Riffgat with its 108MW was the only German offshore wind park grid connected during the first half of the year, bringing the country's accumulated offshore wind generation capacity to 628.3MW.

Another 126 wind turbines with a combined capacity to generate 542.7MW have already been erected off Germany and are currently awaiting their grid connection, according to half-year data from consultancy Deutsche WindGuard.

In total, 3.3GW of offshore wind energy is currently in construction, already erected or grid-connected in German waters.