DolWin kappa offshore substation sets sail
Dutch/German grid operator TenneT said on Monday that the 900 MW offshore substation platform DolWin kappa had left the Dragados Offshore shipyard in Cadiz, Spain.
“TenneT will soon reliably bring even more green wind power from the German North Sea to shore via the DolWin6 direct current connection,” TenneT said in the sailing announcement that took place on August 5, 2022.
“After only three years of construction, the platform is now on board the transport barge “Iron Lady” and on its way to the Dutch port of Rotterdam. There it will be reloaded onto the largest service vessel in the world, the “Pioneering Spirit,” and then shipped to the installation site. The grid-connect system is expected to go live in 2023 and provide renewable energy to more than one million homes,” TenneT said.
“TenneT takes its mission seriously and is advancing the network expansion in the North Sea step by step. With the successful launch of the DolWin kappa offshore platform, we have taken another important step. DolWin6 is already the 13th offshore grid connection in our German portfolio and will strengthen the energy independence that Europe urgently needs from 2023,” said TenneT COO Tim Meyerjurgens when the rig set sail.
“We also have our partners to thank for reaching this milestone on time. Working closely with our contractors, Siemens Energy and Dragados Offshore, my colleagues took only three years to build the platform despite the enormous challenges posed by the pandemic. This is an exceptional achievement – and proof that we have strong and reliable partners,” added Meyerjürgens.
The platform consists of a foundation structure (jacket) and a superstructure (topside). The two have a combined height of about 82 meters, so the platform will rise about 53 meters above the surface of the North Sea. In addition, there will be a bridge that will connect DolWin kappa to DolWin beta (DolWin2 network connection system), which was put into operation in 2016, to effectively use the already existing infrastructure of the mother platform.
In addition, the overall optimized platform design has greatly reduced the size of DolWin kappa.
“The well-thought-out construction of the offshore platform conserves important resources while minimizing environmental impacts. This clearly illustrates that protecting the environment and nature is our top priority when planning and implementing our grid connections,” said Tim Meyerjürgens.
Upon arrival in Rotterdam, the rig will be reloaded onto the largest service vessel in the world. Owned by Allseas, the 382 meter long “Pioneering Spirit” will transport all components of the platform (jacket, topside, piles and deck) to their final destination in the German North Sea.
After the platform is commissioned in 2023, it will convert the alternating current generated by the offshore wind farms into direct current, which will then be transmitted to Hilgenriedersiel on the mainland via an approximately 45 kilometer long submarine cable. .
From the landing in Hilgenriedersiel, the electricity will be transmitted to Emden via an overland cable, which will also be 45 kilometers long. Here on earth, TenneT built the Emden/Ost converter station and transformer station to convert direct current back to alternating current and then feed it into the high-voltage grid at the correct voltage level.