Offshore wind power

The potential of offshore wind is enormous. It could meet Europe’s energy demand seven times over, and the United States energy demand four times over.

Offshore wind is a relatively new technology, so costs will reduce and the technology will advance, helping offshore wind to be more efficient and cost competitive in the near term. But this exciting technology is already being incorporated into government’s energy planning around the world.

More than 91% (11,028 MW) of the world’s offshore wind power is currently installed off northern Europe, in the North, Baltic and Irish Seas, and the English Channel. However, governments outside of Europe have set ambitious targets for offshore wind and development is starting to take off in China, Japan, South Korea, Taiwan and the US. The GWEC-led FOWIND consortium is developing an offshore wind roadmap for India, and other markets, such as Brazil, have raised interest in future offshore development.

Offshore wind is an essential component of Europe’s binding target to source 20% of final energy consumption from renewables, and China has set itself ambitious targets for installations off its coast by 2020. The United States has excellent wind resources offshore, and many projects are under development.

The key benefits of offshore wind are:

  • The wind resource offshore is generally much greater, thus generating more energy from fewer turbines;
  • Most of the world’s largest cities are located near a coastline. Offshore wind is suitable for large scale development near the major demand centers, avoiding the need for long transmission lines;
  • Building wind farms offshore makes sense in very densely populated coastal regions with high property values, because high property values makes onshore development is expensive sometimes leads to public opposition.

Although offshore wind is often the most talked about part of the wind sector, today it represents about 3% of global installed capacity. In 2015 3,398 MW of new offshore capacity was added, bringing the total to over 12,107 MW.


Click graph for a close-up image.  

Global and Annual Cumulative Offshore Capacity (2011-2015)


While electricity from onshore wind farms is already cheaper than conventional power in an increasing number of markets, relatively high costs remains the biggest challenge for offshore wind development. However, according to a study[1] commissioned by E&Y in 2015, offshore wind cost could be reduced to EUR 90 per MWh (USD 94) by 2030. The report says that the sector will have nearly reduced the LCOE to EUR 100 per MWh by 2020, by which time cumulative installed capacity in European waters is expected to have reached 23.5 GW.

[1] Offshore Wind in Europe: Walking the Tightrope to Success, Ernst & Young, 2015.

Key actions to reduce cost include: deploying larger turbines to increase energy capture (a 9% saving); encouraging greater competition (7%); commissioning new projects – keeping volume up (7%) and tackling supply-chain challenges (3%).

At present, the average offshore wind turbine size is 4.2 MW, average water depth 27.1 meters and average distance from shore 43.3 km. The average size of a grid-connected offshore wind farm in 2015 was 337.9 MW.


In 2015, an astounding 3,034 MW of new offshore wind capacity came online in Europe, a 108% increase over the 2014 market. Offshore wind accounted for 24% of total EU wind power installations in 2015, up from 13% share of annual additions in 2014.

Overall 419 new turbines were erected in 2015. Also for the first time offshore turbines were decommissioned. A total of 7 turbines in the UK and Sweden were decommissioned, resulting in a net addition of 412 turbines. A total of 14 projects were completed in 2015.

Over 75% of all net capacity brought online was in Germany (2,282.4 MW), a four-fold increase in its grid-connected capacity compared to 2014. This was in large part due to the delay in grid connections finally coming online in 2015.

The remaining installations in the EU took place in just two markets. The second largest market was the UK with 572 MW, and an 18.7% share of total installations. The Netherlands follows with 180 MW, a 5.9% share of the market.

[1] Offshore Wind in Europe: Walking the Tightrope to Success, Ernst & Young, 2015.Our projections show that by 2020, offshore wind will be about 10% of global installed capacity.

For more details about offshore wind development worldwide see latest GWEC’s Global Wind Report Chapter on Global Offshore here.