Wind Map of Denmark
How to Read the Wind Map of Denmark
This unique map of Danish wind speeds takes local terrain ( speed up effects) and roughness into account. It shows a much more detailed picture of wind conditions than we saw on the previous page. We can clearly see that West and Southwest are the prevailing wind direction in Denmark, since West and Southwest facing coastal sites have by far the highest energy content of the wind (the red and yellow areas).
The map is actually a very high resolution map, where the area of the whole country (44,000 km 2 area) was divided into 1.1 million squares 200 by 200 m each (220 by 220 yards), and the mean wind speed was calculated for each square. You may download the map in various resolutions from the web site of Energy & Environmental Data in Denmark, if you wish (it is also available on CD-ROM).
Using the Wind Map for Planning
This wind map was developed to assist the Danish municipalities in their planning (zoning) work for wind turbines. Each municipality in Denmark is responsible for allocating suitable areas for wind turbines in order that the Government may fulfill its plans to supply 50% of the country's electricity consumption by wind energy in 2030.
Using the Wind Map for Wind Prospecting
The map is obviously also a gift to wind project developers, who can see the (probable) best wind fields in the country directly. One could therefore hardly imagine it being financed and published by any other institution than a government.
The map, however, is not sufficient for actually locating a wind turbine, since it was generated mechanically, without detailed verification in the terrain. In order to make proper calculation of annual electricity output one would have to go to the prospective site and verify e.g. the roughness and locate obstacles and check for new buildings, trees etc.
State of the Art Methods of Wind Assessment
This map was produced for the Danish Energy Agency by Energy & Environmental Data , a wind energy software and consultancy firm in collaboration with the Wind Energy Department of Risoe National Laboratory , which developed the basic fluid dynamics software used for the wind calculations, the WAsP programme.
Calculating such a detailed wind map of a large area is actually an enormous task: The map was made on the basis of extremely detailed digital maps at the scale of 1:25000. The maps in reality consist of 7 layers, with one layer representing altitude contours (orography), another forests and fences (and even individual large trees), a third layer buildings, a fourth layer lakes and rivers etc. The programme that generates roughness data for the WAsP programme determines terrain contours and contiguous areas of forests, lakes, cities etc. in neighbouring squares of each square out to a distance of 20,000 m in all wind directions.
The results were subsequently recalibrated using statistics from several hundred wind turbines scattered throughout the country for which energy output data are available. Thus it has been possible to compensate for the fact that the mean wind speeds in Denmark tend to decrease, as we move towards the East.
© Copyright 1997-2003 Danish Wind Industry Association
Updated 1 June 2003