What's New in WAsP 9?

Compared to previous versions, WAsP 9 contains new functionality, an improved user interface, an improved help facility and several new or updated auxiliary software packages. The most profound changes may be listed under the following headings:

  • Spatial image underlays
  • Nested wind farms
  • Wind farm power curves
  • Resource grid masking
  • Resource grid performance improvements
  • A new WAsP Climate Analyst (separate installation)

These, and some other minor changes, are described in more detail below.

System requirement changes

Windows XP or later is recommended. It is no longer possible to install and use this software on Window 98, ME and NT4. Various updates and patches from Microsoft may be required for WAsP to be installed and run on Windows 2000.

New hierarchy member types

Spatial images

  • These are bitmap image files which can be used as map underlays
  • They can be inserted in various places in the hierarchy
  • More than one image can be associated with the same vector map
  • Add them to the hierarchy by opening a JPG or BMP from file
  • The spatial location of the image is read from an SCL file with a matching file name
  • The WAsP Map Editor can be used to establish the SCL files

Turbine site groups

  • Wind farms can now have sub-groups into which turbine sites can be organised
  • These sub-groups are called 'Turbine site groups'
  • A turbine site group becomes a wind farm automatically if it's not a sub-group of another wind farm
  • A wind farm moved to be a child of another wind farm becomes a turbine site group automatically
  • Turbine site groups are similar to wind farms, but wake calculations are not available

Reference sites

  • A new hierarchy member, called 'Reference site' is introduced
  • The main purpose is to support the calculation of wind farm power curves
  • Reference sites are similar to turbine sites, but don't calculate production using a power curve
  • They can be inserted in various places in the hierarchy, but only one can be at any given level


  • A note is just a snippet of text which can be added anywhere in the hierarchy

Calculation behaviour

Project level calculation

The project-level calculation command 'Do all feasible calculations for all project members' now forcefully recalculates all the members of the project, regardless of whether their results are due for recalculation or not.

Automatic calculation

  • Turbine sites, reference sites, met. stations and wind atlases now always calculate automatically
  • Calculations for resource grids and wind farms must always be explicitly invoked

Wind farms

Nested groups

  • Wind farms now support nesting: sub-groups can be arranged under the wind farm
  • Different sub-groups can have different associated WTGs and obstacle groups, etc.
  • An organiser tool helps to sort and order the children of a wind farm if it gets too untidy
  • Wake effects are calculated among all of the turbine sites in a nested wind farm

Power curve

  • The wind farm power curve is now calculated for a given reference site location

Resource grids

Calculation masks

  • Grids are still defined as rectangles, but a 'mask' can now be defined for the calculation. Masked areas won't be calculated
  • Masks can be defined by selecting map polygons, or by using a Surfer grid map
  • Access this feature via the 'Edit mask' button in the resource grid window

New results

  • Grids of DRIX values can now be calculated
  • Obstacle effects are now included in the calculations
  • Sector-wise results can now be displayed
  • The colour palette used to display the grid results can now be pivoted (centred) around a given value
  • All version 9 resource grids are WRG export-ready (for WindFarmer)
  • A detailed statistical panel shows provides more insight into the grid data


  • The site effects, wind climate and AEP are now handled as separate calculations, so you can make site assessment grids without an atlas.
  • If a grid is re-configured, existing valid results are preserved as far as possible, to minimise the re-calculation task
  • If only the associated atlas (regional wind climate) is changed, then the site effects are not recalculated
  • If only the associated WTG is changed, then only the AEP results are recalculated
  • The grid calculation routines have been changed to make them generally faster


  • It's now possible to open BNA and BLN files
  • Vector maps can include boundary lines which are shown on the map
  • Height contour labels can be shown on vector maps
  • A bunch of new scripts...
2 APRIL 2020