WAB: WindEurope Report Underestimates German Offshore Wind Potential

German wind energy agency WAB has brought into question the results of a report recently published by WindEurope, saying that Germany’s offshore wind potential is around 21GW higher than stated in the report.

According to the report, the potential of offshore wind capacity in German waters by 2050 accounts to some 36GW.

However, WAB has cited a Fraunhofer study from 2017 which established that Germany’s offshore wind capacity is 57GW.

”Our analysis shows that the authors of the WindEurope report use unrealistic assumptions.We support the goal of the European Commission’s “European Green Deal” to exploit the full potential of offshore wind energy in Europe. At 57 gigawatts however, the full potential of the German North and Baltic Seas is significantly higher than estimated by WindEurope,” WAB said.

The BVG Associates report commissioned by WindEurope intends to show “that it is feasible to deploy 450 GW by 2050 and where this capacity could be located most effectively”. According to the report, these 450GW would cover 30 percent of Europe’s electricity needs.

Commenting on the report’s findings, WAB said that ”…the maximum of 35.5GW of offshore wind allocated in German waters is misleading.’…’  and that ”…There is reason to believe that the authors make questionable assumptions.”

According to the agency, this becomes evident using the German North Sea as an example. The authors assume that an area of ​​6,200 square kilometers is suitable for offshore wind farms. For this area, however, they only foresee wind farms with a capacity of 31GW, WAB said. This corresponds to a so-called “power density” of 5MW per square kilometer.

This is an extremely low value that has little to do with the reality in German waters, according to WAB. An extremely low power density would go hand in hand with a very large distance between turbines and would lead to increased costs: The cables required for the inter-array network would be unnecessarily long, as would the distances between turbines for the service personnel. Most offshore wind farms built so far in the German North Sea – as well as the currently planned ones – therefore achieve a power density that is about twice as high, according to WAB. The two examples that the agency gives are Ørsted’s Borkum Riffgrund 2, which went into operation this year and which features a power density of 10.4MW per square kilometer, and EnBW’s project Hohe See which comes at 11.8MW per km².

Germany’s competent authority BSH also maps out future wind farms with a power density of 9-10MW per km², WAB said.

”If the authors of the WindEurope report had used this “official” data ​​as a basis for their assessment, they could have come up with an installed capacity of 55.8-62GW in the German North Sea alone – given the area of ​​6200km² that they considered suitable until 2050. This corresponds with the potential 57GW in German waters by 2050 calculated by the Fraunhofer Institute for Wind Energy Systems on behalf of the German Offshore Wind Energy Foundation. The Fraunhofer report also states that Germany needs to tap its entire realistic potential of all renewable technologies to become climate neutral by 2050. In this regard it is not helpful if an industry association discounts the expansion potential in one of Europe’s most important offshore wind markets,” WAB said.

Responding to WAB’s comments on the report, Giles Hundleby, Director BVGA Associates and one of the authors of the report, said: ”Coming to offshore, global experts agree that 5MW/km2 is a good density to use to optimise the trade-off of cost (which increases with lower densities due to longer array cables) and production losses (which reduce with lower densities due to less interference from turbine wakes with other turbines down wind). In some cases where space is a constraint, then higher densities have to be used. There is plenty of space in German waters for them to play a huge role in offshore wind, even at 5MW/km2. Also worth noting the values in the WE report are as a share of 450GW in Europe not a national limit.”

On the other hand, WAB has agreed with other statements in the WindEurope report, like the need for governments to ensure stable framework conditions for at least ten years and to set ambitious Long-term expansion targets. It is also important that national supply chains for offshore wind can remain stable and grow throughout Europe in order not to become dependent on Imports, WAB said.

Accelerated Special 2GW Tender in Early 2020

WAB has also welcomed the latest initiative by the German coastal states that last month again took a stand for an offshore wind goal of at least 30GW in German waters by 2035. In line with the “Bremen Declaration”, WAB is calling for an offshore expansion path of at least 35GW by 2035. This target takes the production of “green” hydrogen from wind power into account, which can contribute to so-called sector coupling efforts, for example to make the steel, cement, chemical, and transport sectors more climate-friendly, the agency said.

“We welcome the plans of the new EU Commission President Ursula von der Leyen for a European Green Deal. At the same time, we are surprised by the expansion potential for Germany presented by WindEurope,” said Irina Lucke, Chairwoman of the WAB e.V. board.

“We have now reached the industrialization phase of offshore wind technology and have invested a great deal in this pioneering achievement in Germany. The domestic value chain should be able to benefit from this. The good news from our point of view is that we have already been able to show that we can realize 2 GW of offshore wind expansion per year that will be necessary in the years to come.”

According to WAB managing director Heike Winkler, in order to maintain the industrial supply chain for offshore wind developed over the years in Germany, the country needs to establish stable long-term framework conditions and also an accelerated 2GW special tender in early 2020 at the latest, as stipulated in the coalition agreement of Germany’s federal government in 2018.

“This way, free converter capacities can be used economically,” Winkler said.

”If, on the other hand, the Federal Government plans to expand the offshore wind expansion gap by several years, we will not only miss the opportunity to benefit from the internationally growing export market of offshore wind. Germany would then be reliant on electricity imports in order to be able to achieve its own climate targets and would also become an importing country with regard to green hydrogen.”