Press
Bremerhaven, Oct. 19, 2015
Ninth National Maritime Conference, Bremerhaven, October 19-20, 2015
Siemens revolutionizes grid connection for
offshore wind power plants
 Milestone for offshore wind power and the energy transition
 New connection solution can drive the price of offshore wind power below
ten cents per kilowatt hour by 2020
 Total cost decrease of 30 percent
 Transmission capacity increased by 33 percent, transmission losses
decreased by 20 percent
Siemens has introduced a new solution for connecting offshore wind turbines to the
grid. Presented at the National Maritime Conference in Bremerhaven, this directcurrent technology enables a cost-efficient and simplified connection of offshore
wind power plants far from the coast. The platform housing the transmission
technology is much smaller and more compact than before. Until now, these plants
have been connected to the grid via large central converter platforms. Siemens is
now further developing the transmission technology, enabling a large number of
much smaller platforms to be built. With the new solution, a direct-current cable can
connect several of these platforms sequentially in a wind farm and then route them
to an onshore transformer substation. Overall, this solution costs less and is also
more efficient than the approach used with conventional platforms.
The compact design permits encapsulated high-voltage electrical equipment to be
used – especially diode rectifier units (DRUs), which are installed instead of the
usual air-insulated transistor modules. The system is also modular and flexible when
it comes to installation. The volume of the platform structures is reduced by fourfifths, and the weight is cut by two-thirds. As a result, costs are reduced by more
than 30 percent. At the same time, the new solution enables transmission capacity
to be increased by one-third, while transmission losses fall by one-fifth. This is a
Siemens AG
Communications and Government Affairs
Leitung: Stephan Heimbach
Informationsnummer: PR2015100358EMEN
Wittelsbacherplatz 2
80333 München
Deutschland
Seite 1/3
Siemens AG
Presseinformation
significant step toward significantly reducing the cost of offshore wind power and
making it competitive compared with conventionally generated electricity.
"As the only provider on the market, we have already successfully commissioned
four offshore direct-current connection projects . Now we are applying our
experience directly to the next generation of direct-current grid connections. Our
new solution will play a major role in decreasing the cost of offshore wind power
below ten cents per kilowatt hour by 2020. This is how we plan to make the directcurrent technology used in Germany more interesting to other markets, too,” said
Jan Mrosik, CEO of the Energy Management Division at Siemens.
A diode rectifier unit has a transmission capacity of 200 megawatts (MW). Typically,
two DRUs are installed on one platform. Up to three of these new platforms can be
connected to each other to create an offshore grid node that replaces collection
platforms in the wind farms. This link enables a connection to the mainland of
multiple offshore wind farms with a total capacity of up to 1,200 MW. The electricity
is transported to a grid infeed point on land via cables. A converter station converts
the direct current back into alternating current for subsequent transmission and
distribution. The land station will also be built by Siemens using a proven design.
Thanks to high-voltage direct-current (HVDC) transmission technology, the new
system’s transmission losses, including cable losses, are just three percent.
Siemens is a leading supplier of HVDC technology. The use of direct-current instead
of alternating-current transmission to connect wind farms to the grid is made costeffective by the new technology for cable lengths of more than about 80 kilometers.
The core of the new transmission technology consists of the DRU, the transformer,
the smoothing reactor, and the rectifier – all combined in one tank. The use of the
DRUs and the encapsulated DC-CS direct-current switchgear decreases the
installation space by more than 80 percent compared with air-insulated technology.
For the first time, Siemens is using biodegradable ester liquids in the DRU to
insulate high-voltage direct-current equipment. Compared with mineral oils, these
are not only more environmentally friendly, they are also flame-resistant. The DRU
is designed for many years of continuous operation with minimal maintenance
requirements.
Informationsnummer: PR2015100358EMEN
Seite 2/3
Siemens AG
Presseinformation
The new technology is being funded by the German Federal Ministry of Economics
and Energy (BMWi) as part of the federal government’s 6th energy research program
under the supervision of project sponsor Jülich. The research funding provided by
the BMWi in the area of power grids is aimed primarily at advancing the grid
infrastructure and developing it to accommodate the infeed of a large share of
renewable energy.
This press release and press photos can be found at
www.siemens.com/press/PR2015100358EMEN
For more information about the Energy Management Division, please go to
www.siemens.de/energy-management
Contact person for the business press
Stefan Wagner
Tel.: +49 89 636632041; email: sw.wagner@siemens.com
Contact person for the trade press
Sabrina Martin
Tel.: +49 9131 7-37168; email: sabrina.martin@siemens.com
Follow us on Twitter: www.twitter.com/siemens_press
Siemens AG (Berlin and Munich) is a global technology powerhouse that has stood for engineering excellence,
innovation, quality, reliability and internationality for more than 165 years. The company is active in more than 200
countries, focusing on the areas of electrification, automation and digitalization. One of the world’s largest producers
of energy-efficient, resource-saving technologies, Siemens is No. 1 in offshore wind turbine construction, a leading
supplier of combined cycle turbines for power generation, a major provider of power transmission solutions and a
pioneer in infrastructure solutions as well as automation, drive and software solutions for industry. The company is
also a leading provider of medical imaging equipment – such as computed tomography and magnetic resonance
imaging systems – and a leader in laboratory diagnostics as well as clinical IT. In fiscal 2014, which ended on
September 30, 2014, Siemens generated revenue from continuing operations of €71.9 billion and net income of
€5.5 billion. At the end of September 2014, the company had around 343,000 employees worldwide on a continuing
basis. Further information is available on the Internet at www.siemens.com.
Informationsnummer: PR2015100358EMEN
Seite 3/3