Offshore grid connections

Offshore grid connection solutions for efficient and reliable power transmission at sea

Connections to a secure, reliable, and more decarbonized world of energy

Integrating renewable energy sources and decarbonizing existing electricity infrastructure are key to meeting society’s energy needs while fighting climate change. Yet, these contributions to more carbon-neutral energy take place in remote areas often hundreds or even thousands of kilometers away from the centers of consumption. Effective solutions are vital to connecting all distributed power generation sources to the grid to make electricity available where it is really needed.

Siemens Energy supplies a comprehensive range of reliable, efficient, and proven transmission systems as grid access solutions that meet and master these challenges.

Offshore renewables

Offshore electrification

Floating substations

Renewables such as wind power (on- and offshore) play an increasingly important role in the energy mix and contribute considerably to the reduction of carbon dioxide emissions.

Siemens Energy supplies the entire of products and services to turnkey solutions required for efficiently harnessing the power of offshore renewables and getting the energy to the end consumer. This includes wind turbines and complete grid access solutions in HVAC and HVDC technology as well as monitoring and control solutions and operation and maintenance services.

Worldwide lowest emissions in offshore oil and gas production with offshore electrification solutions.

Increasingly also Oil & Gas companies are energizing their offshore installations by the means electrical energy.

Our HVDC and HVAC solutions supply industrial offshore sites efficiently with clean and reliable power. Siemens Energy`s HVDC and HVAC grid access and power supply solutions have proven their superior performance, reliability and availability in numerous projects all over the world - in the harshest climates.

Floating offshore wind opens the door to larger and deeper offshore areas with higher wind potential. Siemens Energy offers optimum floating substation solutions for the connection of floating offshore windfarms to the grid or floating power from shore to open the next frontier for renewables.

From small modular HVDC power from shore applications, or floating HVAC substations, up to full-scale +1 GW floating HVDC solutions, Siemens Energy can offer a lean and innovative floating substation solution for the most challenging environments, based on long-term proven high-voltage technology, and optimized for minimal environmental impact.

With clean air GIS solutions, ester-insulated transformers and closed cooling systems, the Siemens Energy floating OSS offers a valuable and sustainable grid connection for the future of floating windfarms.

There are many challenges to be faced in today’s energy world that is fundamentally changing at a rapid pace. Electricity must come from renewables such as wind and solar power. Power generation must be as carbon-neutral as possible. The distance between power producers and consumers is increasing because renewables resources like offshore wind farms are further away from consumer centers. Grid capacity is growing as fossil power generation is gradually shutting down.

This swiftly-advancing energy transition demands major changes to power grids, making it crucial to stabilize existing, strained grids to ensure continuously reliable operation. Guaranteeing security of power supply and consequently the security of reliable operation of such critical infrastructure is a matter of utmost priority. And while digitalization enables new technologies and solutions, it comes with the burdens of cybersecurity.

Zero-subsidy renewables

As a pioneer in offshore power transmission technologies and reliable partner for implementing high-voltage direct current (HVDC) and high-voltage alternating current (HVAC) solutions as well as flexible AC transmission systems (FACTS) and a comprehensive range of related services, we support you with our in-depth, long-standing experience in the field of power transmission and distribution.

With our holistic approach to the entire electricity transmission system, our experts drive continuous development in terms of both technology and economy. Collaborating with our customers, we deliver significant savings in the levelized cost of energy (LCOE) while further improving transmission system reliability and ensuring grid code compliance. And our expertise supports the zero-subsidy initiative for offshore projects.

Offshore grid connections for every need

Click on the various areas of application to learn more

Offshore Grid Connections Energy Landscape

The benefits you reap

Expertise you can count on

Turnkey solutions

We take responsibility for your entire projects, from pre-engineering right through commissioning, keeping your projects on time and on budget. And if you need long-term maintenance, we can provide that as well.

Proven track-record 

We’ve been renowned for decades for meeting the highest standards in the energy sector. With our in-depth knowledge and state-of-the-art technology portfolio, we’re able to offer a broad range of offshore gird access solutions custom-tailored to your needs.

Reliable partner

You're faced with important decisions concerning the future of your energy assets. How can you ensure your operations will remain successful in future? Let Siemens Energy be your long-term partner, supporting your projects anywhere, over any time – even over decades. Consult with us, and you can rest assured that, together, we’ll find the optimum solution to fit your needs.

Reliable performance 

We’ll help you ensure that your assets deliver continuously reliable performance by using advanced monitoring and control systems. These systems keep your performance right in line with our projections – and possibly even better.

Connecting offshore wind power to the grid and shaping the future of energy supply.

Key to offshore wind farm efficiency is the overall wind farm design, from the turbine generating the power, through the cables transmitting the energy and the on and offshore substations that clean up and stabilize the electricity connected to the grid.

Mike Grainger, Sales Director for Transmission Solutions in the UK

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Our proven track records

We deliver what we promise



  • HVDC PLUS technology connects EnBW He Dreiht wind farm to German shore via a 230 km cable connection with 900 MW power rating (capacity) and voltage levels of ± 320 kV DC, 380 kV AC, 50 Hz
  • 66 kV direct connection of the wind farm to the converter platform
  • Direct current compact switchgear (DC CS) for ± 320 kV DC included to save approx. 95% of space compared to conventional solutions


  • HVDC PLUS technology connects Gode Wind 3 wind farm and other wind farms to German shore via a 90-km cable connection with 900 MW power rating (capacity) and voltage levels of ± 320 kV DC, 380 kV AC, 50 Hz
  • 155 kV AC, 50 Hz connection from the HVDC platform to the wind farm
  • Direct current compact switchgear (DC CS) for ± 320 kV DC included to save approx. 95% of space compared to conventional solutions
ej equinor p2

Johan Sverdrup Phase 2

  • Siemens Energy was chosen to deliver the HVDC system and equipment to transfer the significant power volume of 200 MW with high efficiency from onshore to offshore.
  • By transporting green energy from onshore to Phase 2 offshore, Equinor can reduce CO2 emissions by more than 620,000 tons.
  • The power distribution systems of Step 1 and Step 2 can operate in parallel to ensure high flexibility of power supply for the entire oil field – a novel application of HVDC systems.

Moray East

  • The Moray East project has a capacity of 950 MW – Siemens’ largest UK grid access project to date
  • Siemens is to deliver the onshore substation and three offshore transformer modules (OTM®)
  • Once commissioned, Moray East will deliver enough clean energy to power almost one million UK homes

Triton Knoll

  • Siemens is to design, supply, and build the onshore substation and two offshore transformer modules (OTM®) with a capacity of 860 MW
  • Triton Knoll is the 10th UK offshore wind farm that Siemens has connected to the mainland
  • Once completed, Triton Knoll will be able to provide sufficient clean, sustainable power for the equivalent of 800,000 British homes


  • HVDC PLUS technology connects Global Tech I and EnBW Hohe See wind farms to the German shore via a 130 km long subsea cable
  • 900 MW power rating (capacity) with voltage levels of ± 320 kV DC, 380 kV AC, 50 Hz
  • 155 kV AC, 50 Hz connection from the HVDC platform to the wind farm