German wind report shows “repowering” wind turbines could double output by 2030

A new report published by German wind energy industry group Bundesverband WindEnergie (BEW) and regional renewable energy group LEE NRW finds that existing German wind power output could double in output by 2030 purely through upgrades to newer models of wind turbines.

The study, first reported on by German outlet Clean Energy Wire on Thursday, finds that total annual output from German wind power could increase to 200 terawatt hours by 2030 through reporting. This could be up to 500 terawatt hours per year by 2030 with a doubling of the current land area devoted to onshore wind power in the country (from 1% of total German surface area to 2%).

“Today, less than one percent of Germany’s surface is designated for onshore wind power. This already would allow us to cover nearly 40 percent of power demand by 2030. If the share grew to two percent, we could cover almost 100 percent,” said BWE’s Wolfram Axthelm. “Wind can do a lot more: In the past 20 years, technology has made great leaps and bounds. Modern wind turbines produce around ten times as much electricity today as those built at the turn of the millennium.

This must also be better reflected in potential studies by the federal and state governments”, said Christian Mildenberger, Managing Director of LEE NRW. The study predicts the power output intensity of wind turbines used in Germany will increase somewhere between 230 watts per square metres and 350 watts per square metre, resulting in far greater output at current wind speeds as the larger rotors and higher hub heights capture a much greater proportion of the kinetic energy stored in the moving atmosphere.

The study includes a chart that shows a very significant drop in yearly installations of new wind power in Germany (the light grey columns), but also the role of repowering existing facilities to date. Germany’s wind power growth began prior to most other countries, with installations climbing in the early 2000s. This means many of those early sites are ripe for replacement, as their 20-year subsidy contracts come to a close.

In total, the study suggests up to 53 additional gigawatts of new installed capacity could come purely from replacing old models of wind turbines with new models. For the four German regions analysed, the average rated power of turbines could from around 3 megawatts today to around 5.6 to 6.2 megawatts by 2030.

The study comes at a critical time for Germany’s climate ambitions. The growth of wind power, after a surge in growth, has dramatically stalled in the past two years due to problems around transmission congestion, including community backlash to new power lines, alongside negative community responses to new wind power. Despite these roadblocks, renewables in Germany have achieved some important milestones.

Coal power has plunged in the country, and renewable energy has filled the gap as COVID19 significantly reduced demand. Earlier in the year renewables hit a record 61% of power output in February (55.8% of total generation for the first half of 2020), and COVID19 stimulus packages will be partly directed towards attempted to reinvigorate the country’s onshore wind farm industry.

Electricity demand in Germany is expected to increase in the coming decades, due to the predicted rise of electric vehicles, the growth of heat pumps in homes and the production of hydrogen through electrolysis. Over the 2030s, LEE NRW predicts that even this increase in electricity demand, on top of expected growth, could be met by the usage of newer models of turbines that exceed seven megawatts of capacity per unit. “There is no green electricity gap. Today there is only one approval gap that has to be overcome quickly so that we can achieve the climate and energy goals”, said Christian Mildenberger.