[silvestrov]

Current map of wind speed would disagree a lot with Denmark and Germany "correlates strongly": see https://www.windy.com/?55.670,12.530,5

Germany is a big country, so even internally in Germany there is a big difference: right now Stuttgart has 0 m/s while Sylt has 9 m/s.

[MagnumOpus]

Most wind power in Germany gets generated close to Denmark, in the northern plain and offshore in the North sea and Baltic. There are very few wind plants near Stuttgart. (There were lots of nuclear plants in Baden Wuerttemberg though - but they were switched off and not replaced by renewables.)