According to the German Wind Energy Association (BWE), by the year 2050, around 35,000 onshore wind turbines would be sufficient to generate around 770 terawatt-hours of electricity with an installed nominal capacity of 198 gigawatts. That would be just 5,000 more wind turbines than are currently in operation. However, not only would new wind turbines have to be built and installed, a large portion of the currently existing ones would have to be modernized or replaced. According to Philip Matthiessen at BWE, at peak times wind power already accounts for around 40 percent of the energy mix. A study by the German Academies of Sciences has a more pessimistic conclusion.
According to their assessment, in the year 2050 around 65,000 wind turbines plus electricity from solar energy would be needed to provide Germany with enough power. Matthiessen says the various forecasts are based on different assumptions with regard to the output and efficiency of modern wind turbines. On top of this, each newly erected wind turbine must also be connected to the grid, resulting in additional infrastructure costs.
