How do offshore wind turbines work?

Learn how a simple scientific principle combines with cutting-edge technology to capture the natural energy of the ocean breeze and power our homes and businesses.

Offshore wind power plays an indispensable role in the green transition worldwide.

In just a few decades, offshore wind has gone from being an untested idea to a mature and competitive technology produced at industrial scale.

In Denmark, where Ørsted is headquartered, offshore wind power has reduced carbon emissions and contributed to thousands of new jobs and unprecedented growth throughout the country.

Electromagnetism: the basics

Electrical energy can be generated by rotating magnets inside a coil of conductive wire. The big question is how to achieve that rotation.

In conventional power stations, fossil fuels like coal, gas and oil are burnt to heat water, producing high pressure steam that can drive a turbine and, in turn, an electrical generator.

Unfortunately, this also produces carbon dioxide and other harmful emissions, as well as relying on finite resources that need to be constantly extracted from underground and transported to the power station.

In a wind turbine, the rotation is achieved through the clean, natural, and ultimately unlimited power of the wind.

How do offshore wind turbines work

Did you know?

One rotation of a single turbine will generate enough electricity can power an average home for more than 19 hours.

How do we send power ashore?

Each wind turbine sends its power through cables down the tower and under the seabed to an offshore substation. Here the energy is stepped up to a higher voltage ready to send ashore via high-voltage cables. Higher voltage means less energy is lost in transmission.

On land, another substation adjusts the voltage again so that the electricity can be fed into the grid and distributed via power lines to the homes and business that need it.

How do offshore wind turbines work?

FAQs and advantages of offshore wind

  • Is offshore wind good for the environment?
    Yes. Offshore wind is good for the environment because it generates electricity without burning any fuel or emitting any carbon dioxide.
  • Can you hear or see the offshore wind turbines?
    Usually, offshore wind is located many kilometres out at sea, it can hardly be seen from the shore, and can’t be heard at all.
  • What is the main benefit of capturing wind out at sea?
    The wind at sea is stronger, more consistent, and less turbulent than on land. This means more power can be generated more reliably.
  • Why is it better to build wind farms in the sea rather than on land?
    It’s possible to transport much bigger towers and blades by boat than by road, making it easy to construct much bigger wind turbines, generating more power. The sea is a huge place with plenty of space to construct large numbers of turbines, while avoiding shipping routes or ecologically sensitive areas.
  • What do we do with old wind farms?
    When a wind farm eventually reaches the end of its lifespan, it’s either decommissioned, life-extended, or repowered.  Repowering involves replacing the old turbines with the latest larger and more efficient models, while decommissioning means completely dismantling the wind farm.  

    Today, we can recycle 85-95% of the material from a decomissioned wind turbine. In 2021, Ørsted committed to send no more blades to landfill, but instead to explore options for reuse and recycling.
  • What about the impact on birds?
    Wind turbines pose only a tiny danger to bird life. Far greater is climate change, which threatens many species with extinction. Wind power is an important way of reducing that threat.
  • Value of properties near the offshore wind farms
    Offshore wind farms are generally located far out at sea with very little impact on the view. Studies reveal that offshore wind has little to no influence on property prices.
  • How offshore energy coexists with the fishing industry?
    We work closely with the fishing industry when planning, building and operating our wind farms, ensuring peaceful coexistence.