Winds of Change Offshore Turbines More Powerful than First Nuclear Plant
Part 2: A Sea of Megawatts
This is no longer some environmentalist's toy. These are industrial plants surrounded by open water. The 12 wind turbines are in fact 12 power plants, albeit very small ones, each with an output of five megawatts, which just happens to be the same as that of the first nuclear power plant in Obninsk, Russia, which opened in 1954.
The German government plans to install another 10,000 megawatts offshore by 2020, and 25,000 megawatts by 2030.
That would mean another 5,000 of these wind turbines, or 400 wind farms the size of Alpha Ventus. Large swaths of the German Bight would then resemble a pincushion from afar, turning the body of water into a sea of megawatts.
When that happens, dozens of vessels like the Wind Force I will be needed, as well as hundreds of divers and thousands of men like Ralf Klooster. Germany would then be a true republic of wind.
Klooster was involved in the construction of the facility and is familiar with every bolt. He understands Alpha Ventus the way someone understands something he has built himself. "My father is someone who could do everything with his hands. He even built a replica of a horse-drawn carriage for us." His father was a riveter at the Thyssen Nordseewerke shipbuilding company, until the crisis hit the shipyards and he switched to working as a truck driver.
Nordseewerke is now called SIAG, a supplier to the offshore wind industry. The transformer station for Alpha Ventus was built in the former shipyard where Klooster's father once worked as a riveter. "Most people here," says Klooster, "haven't realized yet what wind energy means for the coast" -- namely, the transformation of the economically ailing East Frisia region. Some industry insiders hope that Germany's new energy policy will result in as much as 100 billion being pumped into the offshore wind economy.
Wind Companies Earning Millions
Two leading wind turbine makers, Areva Wind and REPower, have their production plants in the port city of Bremerhaven. Few people in the hinterlands are familiar with the name Aloys Wobben, but the founder of the wind power company Enercon is now a multibillionaire and one of Germany's richest people. Thanks to former Environment Minister Jürgen Trittin, companies that got their start in garages were able to earn millions upon millions during the years when Germany was run by a Social Democratic Party (SPD) and Green Party coalition government. And thanks to the disaster in Fukushima, they will be earning many more millions in the future.
Enercon makes use of shipyards in the northern German cities of Emden, Kiel and Papenburg, has built the first wind rotor ship, and supplies its wind turbines around the world from its headquarters in East Frisia, says Klooster.
E.on, in a joint venture with the Danish energy utility DONG and the United Arab Emirates, is building a 630-megawatt offshore wind farm in the Thames Estuary. The wind farm will have enough capacity to replace a small nuclear power plant.
When the wind blows, that is.
"It blows," says Klooster. In fact, the wind offshore blows at an average speed of Force 5, which is about 30 kilometers per hour, and it also blows much more uniformly than on land.
At the first energy summit in the German Chancellery, on April 3, 2006, it was decided that a large-scale pilot project would be built near Borkum. Three energy suppliers, E.on, Vattenfall and the regional utility EWE, joined forces to form a consortium known as DOTI, which now operates Alpha Ventus. The then Environment Minister Sigmar Gabriel contributed another 50 million for additional research linked to the project.
The site had to be far offshore, outside the boundaries of the Wattenmeer (Wadden Sea) national park, far from shipping lanes and certainly out of view of the canopied beach chairs on the East Frisian resort islands of Norderney and Juist.
The Largest Open Water Wind Farm
The pilot wind farm was to cost about 175 million, a number that eventually went up to 250 million. The farther offshore a wind farm is located, the stronger the wind. But the greater distance from the coast also makes the project most costly and logistically complex.
Alpha Ventus is currently the largest wind farm to be built under open-sea conditions. The work was delayed by a year because of bad weather -- and too much wind.
The assembly of a wind turbine on the high seas is easier than a Space Shuttle mission, but not by much. Ocean currents and high waves make for difficult working conditions, preventing the crane from accurately placing the base, after lowering it through 30 meters of North Sea water, onto the piles that have been driven into the seafloor. In bad weather, three jack-up rigs, a cable-laying ship, various tugboats, a dredger and a guard vessel must wait until conditions improve. This costs several hundred thousand euros a day.
The wind gives and the wind takes. That's Klooster's philosophy.
The tubes for the base had to be rammed 30 meters into the seafloor and then reinforced with concrete. The plants -- the tower, the nacelle and turbine, and the rotor star -- were then built with the help of a jack-up rig. To complicate matters even further, the 100-ton rotor star can only be mounted on the hub when there is no wind at all.
Transported, Calculated and Adjusted
The base elements, which are as tall as buildings, were welded together in Scotland and Norway. The tubes in the seafloor came from Rostock in northeastern Germany, the transformers from Regensburg in Bavaria, and the rotor blade from Bremerhaven and Stade, near Hamburg. Everything had to be transported across the water, calculated and adjusted.
There is a water tank on board the Wind Force 1 so that the water in the collecting tank beneath the transformers can be replaced periodically. On land, a hose would be sufficient for this purpose. But for offshore turbines a tank has be moved from the pier to the ship, transported 60 kilometers and then hoisted into the air from a pivoting deck with a crane.
The Fino 1 is a research platform complete with fish sonar devices, a sonar tower, free fall penetrometers, and radar devices and cameras to track migratory birds. The equipment is capable of tracking every fish and every seal here. Divers take regular samples to determine what kinds of traces sea creatures leave behind. The large conservation groups had insisted on this additional research. The Fino 1 is the wind farm's environment conscience. The migratory bird cameras and other instruments need electricity, and the most obvious solution would have been to lay a cable to the transformer station, but the environment ministry opted to install a diesel generator instead -- the cheaper alternative.