Casualty of War: WWII Explosives Scuttle Windfarm Opening
The ambitious Riffgat wind farm was supposed to open off the German and Dutch coast this month and power 120,000 homes. Now the discovery of unexploded ordinance is causing a costly delay.
Over the last 14 months, one of the most ambitious offshore wind power projects in European history has taken shape off the coasts of Germany and the Netherlands: 30 enormous wind turbines, with an expected total output of 108 Megawatts -- enough to power 120,000 homes -- are being erected, at great cost, in the North Sea. Now the Riffgat offshore wind farm has encountered an inconvenient, and very old, obstacle (or rather, obstacles) on the sea floor: unexploded World War II munitions.
The project was to be a major milestone for both the German offshore wind industry and Germany's energy transition, or Energiewende, from nuclear and polluting sources of energy to renewable ones. In order to build the turbines, which stand on 70-meter (230-foot) columns, EWE had to use a specially built 132-meter-long ship capable of raising itself above the waves on stilts so that it could assemble the carefully calibrated turbines without being jostled. The turbines can have, at most, 0.1 percent curvature, a limitation which requires extremely precise construction.
An Undersea Graveyard for Explosives
Two weeks ago, Tennet announced that it would not be able to complete the 50-kilometer-long cable connecting the wind farm to the mainland, because explosives were found in the area where the final section of the cable was to be dropped. During World War II, the North Sea was heavily mined, and bombs were often dropped into the sea by British planes on their way back home, in order to save on fuel, creating an undersea graveyard for explosives. German government experts believe 1.6 million tons of old explosives are located in the waters off Germany.
Only a handful of companies have the qualifications and equipment to remove seafloor explosives -- the special ship required for it costs up to 200,000 per day -- and according Lau, the explosives won't be cleared until late August. By that point, the ship that is supposed to lay the cable will already be booked for work elsewhere, until early 2014. Now the plan is to be finished by mid-February. In the interim, Tennet is required to reimburse EWE for 90 percent of the losses incurred by the delay -- costs the Berlin daily Die Tageszeitung recently reported might run as high as 6 million a month. Costs that, of course, may be passed on to German households in the form of grid use fees.
Ironically, the turbines are currently being powered by a diesel generator, because they need to continue moving to avoid gathering rust. Given the latest developments, Riffgat may be an energy drain, instead of an energy producer, for quite some time.
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