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trailer world Issue One 2012

Title 12      Ausgabe Eins 2012 as buildings, walls or trees. It can also be rotated around its own longitudinal axis to minimise wind resistance. The adapter is mounted on platform wagons, which can be coupled together in series. Each system stands on a foundation which is fixed to the seabed. There are different variants: “Bard Offshore I” uses three-legged, so-called tri- piles, which the company assembles in Cuxhaven. Three tubes are rammed 40 metres deep into the seabed. A 450-tonne support joint is then “thread- ed” into the tubes from above – 100 kilometres off the coast and still in the face of strong winds. The coordination of such operations requires highly experienced personnel, and a crane which is able to move heavy parts quickly. Transport over long distances is less of a challenge for offshore work, says Kölling. More important are efficient solutions when it comes to such things as attachments: “The support joint is brought to the site on a pontoon, and it must be securely fastened so that it does not fall overboard, but must also be released quickly.” Many of the personnel were formerly employed in shipyards and are used to the handling of heavy materials with large dimensions. “Most of them still say however that offshore is a completely dif- ferent matter”, says Andreas Kölling, company spokesman for BARD Holding. “Where else do they make ten centimetre thick weld seams?” Again and again, the challenge lies in size: “Off- shore means work accurate to the millimetre with large and difficult dimensions. We are dealing here with huge parts, which at the same time must be handled very accurately”, he explains. “Imagine, for example, that they must install the foundation into the seabed: three tubes each weighing 440 tonnes and 90 metres long, with a diameter of 3.40 metres, which are stored horizontally on a pontoon, which is also rising and falling with the waves, first have to be brought into a vertical position and then in- serted into a driving template – with a tolerance of a hand’s width.” The pontoon is custom-built, just like other, es- pecially powerful and also particularly expensive ships which provide the farms with material. The “installation logistics” – the transport of personnel and material from the dockside – makes up the largest part of the costs. Offshore farms today still cost three to four times as much as a comparable coal-fired power plant – whilst over 20 years of op- eration they save the climate 17 million tonnes of carbon dioxide. Further weak points are the many ports that are not yet adequately equipped; there is a shortage of storage space, access roads capable of handling heavy loads and dockside length. How- ever, the port is perhaps the most important hub for the logistics of the projects, particularly in the future when more and more component manufac- turers will move to the coast. A 250-megawatt farm with 50 5-megawatt individual systems means a vol- ume of about 100,000 tonnes that has to be moved. BARD buys in the tower segments and the so- called foundation tubes. “We build the rest our- selves”, says Kölling. These include components such as the generator nacelles, the rotors and also the support joints for the foundations. The com- pany was founded in the year 2003, the first ap- provals were received in 2007, and the company now manages 50 foundations as well as 30 systems in the North Sea – 19 of which are already con- nected to the grid. The number of employees has increased during this period from eight to about 1,000. “We started early and quickly. And that is why we ourselves had to build anything that we could not obtain on the market. The availability now looks completely different, everything is slow- ly getting into the swing.” At BARD, the largest part that has to be bought in is the machine bearer – the heart of the machine house and a massive cast iron part of 6.50 metres in diameter and 73 tonnes in weight. These come from an iron foundry in Torgelow in Mecklenburg near the Baltic coast or from a supplier near Stutt- gart. The machine bearer must be laid on its head Photos:TIIGroup,BARDIllustration:Anne-KatrinGronewold A rotor blade is manoeuvred round a difficult curve on an adapter vehicle from Scheuerle. Experienced personnel needed Number of turbine types by 2015 in German projects*/** The German Offshore-Market to 2015 *The difference between the total of the planned tur- bines is due to turbines not yet ordered or known in individual projects. **The difference between the total megawatts of investors and the total megawatts of the turbines is due to turbines not yet ordered or known in individual projects. Investors by 2015** Shares in megawatts (MW) Siemens 2.3 21 BARD 5M 160 Vestas 3.0 176 Total: 1,139 Siemens 3.6 430 REpower 54 AREVA Wind 298 Vattenfall 154 Windreich 660 Dong 288 E.ON 288 Various municipal works 1,496 RWE Innogy 288 Various medium-sized companies 413 Private equity companies 696 EnBW 1,228 Total: 5,261

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