The installed capacity of offshore wind is now 29 GW and the expected growth in wind power will mainly be offshore. The expectations are that Europe will reach 160 GW installed capacity by 2030 according to forecast from WindEurope. Alone in Denmark the planned Energy Island with up to 40 GW offshore will be a massive construction. Not only Denmark has these ambitious targets for the future of offshore wind. Among others, the Netherlands plan 40 GW, Norway 30 GW, Germany 40 GW and the UK 70 GW in 2040.
Looking into 2023 the latest generation of wind turbines now has a capacity of more than 15 MW and expected to reach 62 MW in 2040. The future turbines will cover a massive area with up 500-meter height and with more than 200 GW in 2040. This will be more than 13.000 turbines of 15 MW capacity covering an area of around 568 million m2 by the turbine blades mainly in the North Sea and Baltic Sea. This will have an impact on the wind climate and probably also the weather. The big question is how large the impacts will be. As we have westerlies some parks might be favoured whereas others further downstream might have less wind to harvest.
A study presented in Nature has a decrease of 1 m/s in average for 10 meters wind speed and a 7% increase in the precipitation. The theory for the changes in precipitation is the turbines will react as small hills and force weather up that may lead to higher precipitation locally. Overall, I don’t see this as a result from the buildings as farms also will create lee effects downstream and the changes will be on a very small scale. We do not see big changes in the precipitation pattern in our simulations.
Offshore farm wake studies
At ConWX we have simulated several offshore farm wake studies, using our in-house mesoscale model back in time, we have embedded the turbines in the models. This gives the unique possibility to simulate very large farms. Our studies show significant changes for the neighbouring wind farms but also a relative full wind energy recovery 70- 100 km downstream of very large wind farms.
In the figures an example from 14th February 2022 09 utc with a south westerly wind. There are massive decreases in the wind speed at 100 meters north of the virtual wind farm in this situation a drop of 2-4 m/s. There is also a small speed-up of the wind speed northeast of the virtual wind farm. In situations with stable weather situations, the wake and changes can be massive downstream whereas in more unstable air masses the winds above are easier transported towards the surface.
If you are uncertain about how your future farm will be affected by neighbouring wind farms, simulations for wind and production anomalies are highly recommended.
Yes, decarbonization will change the pattern or strength of the wind in some regions. However, this will be local changes in the very lowest part of the atmosphere and will not change the general weather patterns.