Active in the North Sea for the first time yet then with two offshore wind farms at the same time: EnBW constructed the Hohe See and Albatros wind farms, which have been connected to the grid since October 2019 and January 2020, as one 639.45 megawatt joint project.
They will produce enough green electricity to supply on aggregate all of the private households in the City of Munich. As was the case with our two Baltic Sea wind farms EnBW Baltic 1 and EnBW Baltic 2, we have brought a partner on board.
Hohe See and Albatros at a glance
Far out in the North Sea, the EnBW Hohe See and EnBW Albatros wind farms and their 87 wind turbines are connected to the grid: Hohe See is located around 95 kilometres north of Borkum and around 100 kilometres north-west of Helgoland, while Albatros lies 105 kilometres from each coast. On areas covering 42 and 11 square kilometres respectively, both wind farms have been producing 2.5 billion kilowatt hours of electricity to supply an aggregate of around 710,000 households since January 2020.
- Output: 639.45 megawatts for total project
71 x 7.35 megawatts=521.85 megawatts at Hohe See
16 x 7.35 megawatts=117.6 megawatts at Albatros - Turbines:
71 Siemens SWT-7.0-154 Hohe See
16 Siemens SWT-7.0-154 Albatros
- Annual yield: 2.5 billion kilowatt hours for total project
- Average wind speed: approx. 10.1 metres/second
- CO₂ saving: around 1.9 million tonnes/year for total project
- Foundations: Monopiles
- Hub height: 105 metres
- Rotor diameter: 154 metres
- Water depth: 40 metres
Cooperation partner on board
EnBW invested around 1.8 billion euro in the Hohe See wind farm and an additional 0.4 billion in the Albatros wind farm.
This joint project thus represents the largest investment in the history of the company and brings EnBW closer to its goal of expanding renewable energies into a main pillar of its energy generation.
In order to finance the offshore wind farms from their construction through to commissioning, EnBW secured the Canadian energy infrastructure company Enbridge Inc. as an investment partner: Enbridge Inc. has acquired 49.9 percent of the shares in EnBW Hohe See, while EnBW retained the remaining 50.1 percent.
This investment provides us with scope for the further development of new projects.
EnBW & Enbridge continue their successful cooperation with the Albatros wind farm in the North Sea
Our investment partner Enbridge Inc.
Fully commissioned: At 11:10 a.m. on 5 January 2020, the first of 16 turbines at the Albatros wind farm was commissioned and began feeding electricity into the grid. Four days later, after the 71 EnBW Hohe See wind turbines, all 16 EnBW Albatros turbines were also connected to the grid. The commissioning has thus been successfully completed: Currently, all 87 turbines of the offshore wind farms "Hohe See" and "Albatros" are feeding in electricity. They have a total output of 609 megawatts.
Christmas 2019: Work continues at the wind farms Hohe See and Albatros even during the holidays. Marcel Seidt, service technician for the wind farms, was on duty there until 25 December: "On the Bibby Horizon, we were on the construction site over Christmas as a team of about 20 men, and actually the celebration there is a day like any other: We accompanied the commissioning of the Transition Pieces, i.e. various inspections of the commissioning. Commissioning work is also underway on the OSS and there are various maintenance and service intervals. Only the Christmas decorations with a small Christmas tree in the canteen made it clear that it really is Christmas. Unfortunately I missed a Christmas dinner: Since the Bibby is flying an English flag, Christmas dinner was not served until the 25th night when I was already off.
From the inspection and approval of the ships allowed to navigate in the wind farm area to the coordination of ship movements on the construction site: During the entire installation phase of the Hohe See/Albatros project, Marine Coordination in the EnBW office in Hamburg ensured the smooth operation of all activities at sea on a 24/7 basis. In the picture: Heiko Tetzner and Michael Vandersee (from left).
24 October 2019: On its way to the EnBW service station in Emden, the special ship Bibby Horizon Wavemaster makes a stopover in Hamburg. Following the commissioning of the two offshore wind farms, this high-tech ship that was commissioned by Siemens Gamesa Renewables and EnBW will be responsible for their maintenance and operation. It is 90 metres long and can accommodate a team of up to 60 people consisting of the ship’s crew and service technicians. This ship thus is a floating service station including workshop, warehouse and accommodation. The technicians will spend two weeks at a time at sea and work there until being flown back to land by helicopter.
Friday, 20 September 2019: The last of the 16 wind turbines at the Albatros offshore wind farm was installed during the evening.
Together with the 497 MW from the Hohe See offshore wind farm, a total of 609 MW is now available to be fed into the grid. Following the successful installation of the turbines, the next phase of the work will now focus entirely on commissioning the two wind farms.
In parallel, the last nacelle for the Albatros project has been produced in Cuxhaven, which concludes the production process for the nacelles for the joint EnBW Hohe See / EnBW Albatros project.
All 71 wind turbines at the Hohe See project have been fully erected since 13 August, completing the installation of this wind farm. Work has now started on the erection of the wind turbines for the Albatros wind farm.
The first kilowatt hour of electricity was generated and fed into the grid by the first wind turbine at the “Hohe See” wind farm on 15 July. Eight turbines had generated electricity by the end of July and completed a 10 day test period. More turbines will be switched on in August. Our photo: The “Brave Tern” installation ship is situated next to a wind turbine, while the “Seajacks Kraken” lies alongside the offshore substation on the right of the photo. This ship is used as an accommodation platform at the construction field.
Halfway point reached on 24/06/2019: The 44th turbine for the neighbouring wind farms “Hohe See” and “Albatros” in the North Sea has been erected. More than half of the turbines have now been installed. The “Brave Tern” and “Blue Tern” installation ships each load the parts for four wind turbines at the port of Esbjerg in Denmark and install them at sea onto the foundations anchored into the seabed.
29 May 2019: A busy day draws to a close with a beautiful sunset. The installation of the wind turbines is in full swing, 35 wind turbines have been erected. All 87 turbines for Hohe See and Albatros are due to be installed by October at the latest.
The work to erect the foundations for the EnBW Hohe See and Albatros wind farms was completed on 10 April 2019. The final component to be installed was the transition piece at the AL-24 site. And parallel to that...
…, after weeks of intensive preparations at the port of Esbjerg (Denmark), the installation of the first wind turbine was completed on Saturday, 6 April 2019. Just two days later, the second of the total of 87 7 MW turbines with a total height of 182 m already stood tall against the stiff breeze in the North Sea. Irina Otelea, Offshore Installation Manager at the joint project Hohe See and Albatros, is fascinated by her work during this construction phase. See more.
The substation for the EnBW Albatros offshore wind farm has been installed. The “Pacific Osprey” collected the substation in Rotterdam and then the “Innovation” lifted it into place on the already installed foundations.
The construction of the EnBW Hohe See and EnBW Albatros offshore wind farms is continuing with two new special ships: the jack-up vessel Innovation has been on the construction site since mid-February and is installing the rest of the total of 87 monopiles. The ship Sea Installer is also set to begin work in the near future. It will transport the transition pieces for the later towers of the wind turbines from Rotterdam to the construction site and position them on the monopiles. Both new ships are being used after the Pacific Osprey used in 2018 was no longer operational following crane damage.
All the major components for the OTM have been installed on the platform since the end of 2018. Before the planned load-out in March 2019, the systems are due to be commissioned on the platform.
All of the sea cables for Albatros were also produced in Lochem (the Netherlands) and Hartlepool (Great Britain) and are now on route to Velsen in the Netherlands. As was the case with Hohe See, they will then be collected by the cable installation ship “Spirit” for installation at the wind farm.
An accident has occurred on board the “Pacific Osprey” while carrying out maintenance work on the crane. As a result, an alternative installation vessel must be used to complete the installation of the foundations. Up until the accident, 63 foundations for the Hohe See offshore wind farm had been installed using the jack-up vessel “Pacific Osprey”. In November, the monopiles and transition pieces already loaded onto the “Pacific Osprey” at the port in Eemshaven in the Netherlands were unloaded by the heavy-lift crane vessel “Gulliver”. The installation of the foundations will continue in the first quarter of 2019.
The first nacelles are ready to be shipped in Cuxhaven. They will be transported by roll-on/roll-off ship to Esbjerg by the end of the year, where they will then be loaded for installation at the construction field in 2019.
The first steel plates were cut to mark the start of construction of the ALBATROS OTM (Offshore Transformer Module) in Zwijndrecht, the Netherlands, in February this year. After 5 months of steel construction and coating work, the two decks that had been constructed separately were ready to be joined together. The main deck was positioned and aligned on top of the cable deck. It will still take some time until the work to join the two decks has been completed.
The cable installation ship “Spirit” has transported its first load of cables to the construction field from England. It is being supported by the supply ship “Stril Server”. This ship houses the personnel required for installing the cables at the foundation sites. The first cable was already laid across the seabed between two of the foundation sites and installed on 13 August.
The cables being produced in Lochem (the Netherlands) and Hartlepool (Great Britain) for the array cabling are almost finished. The first sea cables were loaded onto the cable installation ship “Stemat Spirit” in Velsen, near Amsterdam. From there it sailed to England to collect the remaining cables. A total of 130 km of sea cables for the array cabling will be installed for the EnBW Hohe See / Albatros project.
The transformer station (OSS) was loaded onto a pontoon in Antwerp and began its journey to the construction site on 20 June. Once it had arrived, it was hoisted onto the already installed jacket by two cranes aboard the Thialf heavy-lift vessel during the night of 27 June! In the days that followed, the first OSS crew had already completed the installation by carrying out the necessary welding and other work.
The jacket for the Hohe See offshore substation was loaded onto a transport barge at the shipyard in Vlissingen. The journey to the construction field took two days. The floating pontoon with the jacket and the piles was transferred there to the “Thialf” heavy lift vessel and then installed on-site. The substation itself will be installed on the jacket in around three weeks.
The Pacific Osprey has reached the construction field after a 12 hour journey. The installation of the foundations has now begun.
The work has started offshore! Depositing the scour protection is the first task at the Hohe See construction field. This layer of stones prevents the sand at the foot of each foundation from being washed away by the currents at sea. The scour protection is being installed by the vessel “Flintstone”.
Hoboken, Belgium: The OSS is almost finished. The three main transformers each weighing 190 tonnes are now being installed. Each transformer can supply 200,000 households with electricity.
Now too big for the hall: Assembly and fitting of the topside continues outside in all weather conditions. Most of the large components have now been installed.
The 60 metre high jacket stands fully upright in Vlissingen. The first sections of scaffolding are being assembled so that work can be carried out on the jacket at these heights.
Progress has been made with the wind power plants in Hoboken, Belgium: The first two transition pieces have been completed. They will be fitted later to the monopile foundations. The towers for the wind power plants are then connected to the transition pieces.
The first segments of the OSS jacket are erected in Vlissingen at sunrise.
Progress is not only being made with the OSS. In Rotterdam, the first foundations (monopiles) for the wind energy plants have been coated.
The transformer platform in Hoboken, Belgium, is growing. Another deck – the so-called mezzanine deck – has now been fitted.
The four mud mats are being constructed. They are the bottom sections of the jacket foundation. The jacket itself sits on the seabed. A jacket can be used as the base for erecting e.g. a standard wind power plant or, in this case, the transformer platform.
Final assembly at the Hoboken site in Belgium: The first two of the total of four decks are being assembled here one on top of the other.
The individual components of the transformer station (OSS) are fitted together step by step to form sections in Belgium and Holland. The lower deck, for example, was loaded in Vlissingen, Holland, and is then being transported to the final assembly site for the OSS in Hoboken, Belgium.
The construction of the major electrical components has also begun. The photograph shows the core and windings of a power transformer for the OSS. A total of three of these transformers are planned for the OSS Hohe See.
The jackets for the foundations are also already in production. Since January 2017, the basic pipes have been produced in Germany. Once they are ready, the individual pipe segments are transported to Belgium. There they are then coated and fitted with anodes to guarantee protection against corrosion underwater.
The transformer station of the EnBW Hohe See wind farm has been in production since October 2016. Electricity will flow via this station to reach land. The prefabrication of the individual steel components is taking place in Poland, Bulgaria and Belgium. The photograph shows a section of the main deck in April 2017 being moved on a floating pontoon to the coating hall in Balen, Belgium.
Foundations, towers, nacelles, generators and rotor blades, transformer station and wind farm cabling: every single component of the wind power plants and the wind farm technology for EnBW Hohe See and Albatros is being built on land. The components begin their journeys to the construction site in the North Sea from countries including Denmark, Germany, Holland and Belgium. They are then installed at their designated locations where they will reliably generate electricity for the next 25 years.
Short films document the milestones reached during the construction phase
April 2019
After weeks of intensive preparations at the port of Esbjerg (Denmark), the installation of the first wind turbine was completed on Saturday, 6 April 2019. Just two days later, the second of the total of 87 7 MW turbines with a total height of 182 m already stood tall against the stiff breeze in the North Sea. Irina Otelea, Offshore Installation Manager at the joint project Hohe See and Albatros is fascinated by her work during this construction phase.
Hoboken, Belgium: The OSS is almost finished. The three main transformers each weighing 190 tonnes are now being installed. Each transformer can supply 200,000 households with electricity.
Progress is not only being made with the OSS. In Rotterdam, the first foundations (monopiles) for the wind energy plants have been coated. Progress has also been made with the wind power plants in Hoboken, Belgium: The first two transition pieces have been completed. They will be fitted later to the monopile foundations. The towers for the wind power plants are then connected to the transition pieces.
The transformer platform in Hoboken, Belgium, is growing. Another deck – the so-called mezzanine deck – has now been fitted.
The individual components of the transformer station (OSS) are fitted together step by step to form sections in Belgium and Holland. The lower deck, for example, was loaded in Vlissingen, Holland, and is then being transported to the final assembly site for the OSS in Hoboken, Belgium.
Foundations, towers, nacelles, generators and rotor blades, transformer station and wind farm cabling: every single component of the wind power plants and the wind farm technology for EnBW Hohe See and Albatros is being built on land. The components begin their journeys to the construction site in the North Sea from countries including Denmark, Germany, Holland and Belgium. They are then installed at their designated locations where they will reliably generate electricity for the next 25 years.