A digitised map showing all the contours of the site is put into the computer indicating all the obstacles in the vicinity such as mountains, houses, forestry etc. Using the nearest Meteorological Station weather information the software then produces a map with the expected average wind speeds over the various areas of the site.


Why use WAsP?

WAsP provides a cheap estimate of the wind speed and direction on a site. Although it does not give accurate wind speeds for reasons outlined below it does give a very valuable indication of expected wind speeds. It is also necessary for determining how many turbines can fit on a site and where are the best locations for them. In this regard it is completely reliable and accurate. It also allows us to estimate (where we do not have accurate on site wind speed measurements) the output from a particular make of turbine in a particular location within the site. This in turn can be used to show the financial output of the proposed windfarm.

How WAsP works

The Program 'sees' the landscape for l0-20km in all directions from the site, taking into account every contour on the map, every town, village, forest, lake and ocean. Armed with this information it makes its calculations, adding and deducting where necessary, measuring the length, breadth and height of the above mentioned obstacles that cause a drag on wind speed or areas of water, where a speed -up effect will be recognised.

As with any program, its predictions are only as good as the quality and quantity of data available to it. When Meteorological stations first began recording many years ago, high output wind turbines did not exist and there was no real need for the precise wind data that is now required. Wind direction was perhaps more important for shipping forecasts and measuring at 10m was sufficient. Obstacles in the immediate vicinity of a wind monitoring station were sometimes ignored, leading to calculations unsuitable in determining what the wind speed was actually doing 40,50, or 60metres above a mast.
The WAsP program is capable of taking these obstacles into account and adjusting the Met Stations data accordingly and also calculating wind speeds at heights greater than the standard 10m.


Accuracy of the WAsP Model

The WAsP model is normally plus or minus 10% on energy output and depends entirely on the quality of the data from the nearest local Met. Stations for it's predictions. Therefore it is important that on site measurements be carried out to determine both wind speed and direction.


Need a WAsP done on YOUR SITE?

Why not contact us and we will take you through the process.
To get a WAsP analysis of a site will cost EUR640 including VAT.

Click here to return to main services page >>

Home | Contact us | Services | Seeking Site Owners | Heritage | Site Map | Links