SIEMENS WIND POWER: A Bird’s Eye View on the Scale of Offshore Wind Power

Events such as the EWEA OFFSHORE that took place in March, are providing excellent opportunities to hear all about the latest developments and challenges to overcome in the vibrant industry that is offshore wind. But reading and hearing is one thing… Experiencing the real thing is another.

To give Offshore WIND and the articles we write as much real experience and credibility as possible, we try as often as we can to visit the companies working in the different sectors of the industry to get a closer look and better understanding of what is involved. Walking between the large components in the manufacturing facilities of the foundation, turbines, vessels, cable builders, etc. makes us realise their size.

However, it does not happen every day that we can actually face these wind farms offshore, therefore we grab the opportunity whenever we can to join tours to wind farms that are organised by conferences or those specifically organised by companies for the press. And sometimes we are very lucky and that was the case when Offshore WIND was invited by Siemens Wind Power to join them on a press tour on the last day of the EWEA OFFSHORE event in Copenhagen to their turbine assembly site in Esbjerg – by air!

So, after having checked 3 times whether my camera battery was charged and an empty SD card was inserted the evening before I could finally fall asleep peacefully. When I woke up the next morning I could not believe my luck as there was hardly a single cloud to detect in the sky! The meeting point for me and the other press that would be joining also was at the Hilton hotel at the airport of Copenhagen. Here we were welcomed by Cordula Ressing and Sabrina Martin, press officers at Siemens AG who would be guiding us during the day. Our schedule would first fly us straight to Esbjerg where a bus would be driving us to Siemens’ pre-assembly site. Here we would get an update on the current projects that are being handled there. The flight back to Copenhagen would take us across the 288MW DanTysk wind farm where Siemens is working on for their client Vattenfall. Siemens provided 80 of their SWT-3.6-120 turbines, to date the most ordered offshore turbine in the world.

Also present was Michael Hannibal, the CEO Offshore of Siemens Wind Power and Renewables Division, providing us with a brief overview of the current innovations by Siemens and some messages to take with us for when we would be visiting the Siemens assembly site and viewing the DanTysk construction site on the way back in order to really fully understand the magnitude of what is currently been built by the offshore wind industry.

Siemens’ involvement in the offshore wind industry goes back to the very first offshore wind farm Vindeby, in 1991. This Danish wind farm has 11 of Siemens 450KW turbines installed. Nowadays their largest turbine is 7MW, 15 times larger. Mr Hannibal: “That’s innovation that you have never seen in any other industry.” The industry has progressed, not only with innovations but also in industrialisation and scaling, ‘what we see today is a power plant size. It’s not just a turbine or wind farm put on the water, it’s a power plant’, he adds.

The offshore wind industry has moved from being a pioneering industry, to an immature industry and now to an industry that is maturing up, he continues, explaining that this is reflected in the growing interest in financing this industry. New investors are entering the market; pension funds, infrastructure companies and private investors. It’s not just the utilities that are investing in offshore wind, doing this on a balance plant only.

New cost reduction solutions announced

And even though Mr Hannibal thinks that offshore wind is already earning its ranked place as an effective energy production option and, for example, having already beaten nuclear energy, he does confirm that the industry is not yet where it wants to be and is looking for further cost reductions. Siemens are playing their part in working towards cost reductions in all areas of their activities, turbines, grid connection solutions and service activities. At the EWEA event the company launched three new concepts, one in each of these areas, contributing to overall cost reduction. First of all the company introduced a 7MW turbine, an upgraded version of their 6MW turbine with the difference to be found mainly in using new magnets in the nacelle and enhancements in the electrical system.

The second new solution is to be found in the AC grid connection for near-shore wind power plants. Up to now groups of turbines are connected via substations where the AC power generated by these turbines is transformed to a higher AC current. Larger HVDC platforms are used for connecting wind farms further out at sea and especially where several wind farms are located nearby. Here the AC current from the individual substations is collected and transformed to DC current which can be transported by an export cable to the onshore connection with losses below four per cent. But it is in the area of the AC substations where Siemens has worked towards a new solution. Mr Hannibal: “These substations are well functioning but are a complex solution which have therefore a tendency to have a price tag.” The new solution consists of an offshore transformer module (OTM) attached directly to a wind turbine, and acts as a distributed transmission asset. It is nominally rated in incremental 250MW blocks, which can be linked together to provide the required transmission capacity even for very large wind power plants. With the new solution there is no need for a substation. Siemens promises that this could save up to 30 to 45%. “Now that’s a super smart system!”, he adds.

But Siemens activities do not stop once the wind farm is in operation. They also take on responsibility of the maintenance of the turbines, ranging from 2 years service contracts to full responsibility during the lifetime of the wind farm, depending on the customer’s preference. In order to reduce the time, and therefore money, wasted in transporting the technicians and engineers up and down to the wind farms further at sea the company has launched special Service Operation Vessels (SOVs). Read more on these vessels in the next edition of Offshore WIND.

Siemens’ pre-assembly site in Esbjerg

With this in our back minds we quickly left the meeting room as our plane, a Businesswings Dornier 228-212, that would take us to Esbjerg was ready to leave. After an hour flight, enjoying the view of Denmark from the air, we landed at the small airport of Esbjerg where a bus was waiting for us to take us to Siemens’ assembly site. It was hard to overlook the site as the numerous tower components standing upright, waiting for the next installation vessel to pick them up, were clearly visible from a distance. The site is adjacent to that of Vestas and surrounded by companies that are playing their part in the offshore industry such as Blue Water Shipping. As we drove up to the site a bright yellow TP with the Siemens name written on it clearly marked the entrance.

We were welcomed by a local representative of Siemens and handed our personal protection gear that we would be wearing during our tour. Upon arrival we received news that our schedule would have a slight change as a crew change was planned for SylWin1. As the crew change would take place by helicopter it meant that our plane would not be allowed to fly low above the HVDC platform at the same time. It just confirmed how complicated working offshore really is, with planned schedules continuously being updated to adapt to changing weather windows, unexpected activities, etc. So our visit at the site would have to be speeded up a bit but leaving enough time to get a good enough glimpse of what is being done here. And, as in the industry, creative solutions can be born, and so while we would be ‘touring’ the site our planned lunch would be wrapped up to take on board the plane, therefore buying time. In a meeting room we received an introduction to the site. We were told that the pre-assembly site is unique in the world. Over 230 employees work here. In 2014 more than 300 turbines were pre-assembled. The site consists of large storage areas for the different projects and two assembly buildings of which one is for the SWT-6.0-154 turbines. Here the electrical tests are ran. As we would witness later on, there were at that time four projects being handled, Butendiek and Amrumbank West (3.6MW turbines), Borkum Riffgrund (4MW turbines), and Westermost Rough (6MW turbines). At the time of our visit the last of the 35 SWT-6.0-154 turbines for the 210MW Westermost Rough wind farm were waiting for arrival of A2SEA’s installation vessel SEA CHALLENGER which would take them to the site. The vessel is only one of several installation vessels frequently visiting the site.

At the site itself nothing is produced. It is here where all the components for the different type of offshore turbines arrive and where the towers and nacelles are being assembled. The current facilities allow for 6 nacelles to be assembled at the same time. However, the company is working towards speeding up to an assembling rate of 1 a day in the future. It is building a storage hall adjacent the current facility for this purpose. We went quickly back to the main building to return our safety gear and get on the bus that would take us back to the airport. With the size of the these individual components still in our minds we were eager to see them fit as individual pieces, together with the substation and the HVDC platform together into one large completed puzzle, forming a complete wind farm, or to stay in Mr Hannibal words, a power plant!

DanTysk & SylWinl

And what an experience it was! The weather was so clear that we could not only see the entire wind farm, with 80 turbines and a substation installed in an area covering 70km2, but also several vessels, such as the Wind Ambition floatel by C-bed but also the smaller CTVs like the MCS Blue Norther in the wind farm. And then the SylWin1 HVDC platform appeared as a yellow giant rising up from the sea. We could see almost every detail of the platform, the helideck, lifeguard ribs… Even the people who were working on the platform that day, looking like miniature Lego minifigures, which really showed the magnitude of the platform! Siemens has already built 4 for German TSO TenneT of which 2 are fully operational, the BorWin2 and HelWin1 platforms. Two others, the HelWin2 and SylWin1 are installed but are in the testing phase. When we flew over we could just see a small orange rib leaving the platform. A fifth, the BorWin3 will be installed in 2019. But all good things come to an end and at the end of the afternoon we landed back again at the airport of Copenhagen where we said our farewells to each other and our thanks to Sabrina and Cordula for this opportunity! A few hours later I would be taking the plane back to the Netherlands, and even though we would be flying over a few other wind farms being built, in this case the Gemini and Eneco Luchterduinen projects in the Dutch sector, it would be from a far distance and be nothing compared to the experience we had that day.

So I take this opportunity to say a general thanks to all those who opened their doors to us, gave us their trust to learn from what they do so that when we write about the industry it is not just by hearsay! But we know our place and it is really the people who are working in the industry on a daily base that have the in-depth knowledge that makes this industry work. In the next edition we let them share their experience in a dedicated HR section!

Sabine Lankhorst