File-Types

Data can be loaded into Openwind via the File menu or dragged and dropped directly into the mapping window. It is also possible to drag and drop entire directories into Openwind (see below).

Openwind takes a wide variety of file types:

• Images (PNG, BMP, JPG, GIF, TIF). Image files are assumed to be previously geo-referenced. When loading an image file, Openwind looks for a world file and, if successful, uses the information therein to initialize the contents of the Reference Image dialog box (figure 1). If unsuccessful, users may choose the Browse button to search for a world file or they can input the coordinates manually. If you are seeing this dialog because you are trying to load a geotiff which includes projection information, please click on the big button at the top.

Figure 1: Reference Image Dialog

• Vector Layers. Users can load shape (SHP) or KML/KMZ files containing points, polylines, or polygons into Openwind as Point Layers, Line Layers and Polygon Layers, respectively. The use and manipulation of these data types is covered in Vector Layer. WAsP maps (*.MAP) can also be loaded into Openwind as terrain data and the software will scan the roughness change lines to produce a roughness length raster (although this can take a while depending on the size).
• Raster Layers. Users may load ESRI ASCII grids (.ASC), ESRI binary floating point grids (.ADF), GeoTiffs (.tif), Surfer grids (.grd), Idrisi grids (.RST), WindFarmer DTMs (.DTM), binary interleaved grids (.BIL), Canadian CDEDs and ASCII xyz (.XYZ) files into Openwind. Once in Openwind, they become Raster Layers, which are grids of floating point values indexed by a location (x, y). We will cover Raster Layers in .
• Wind Resource Grids. The industry standard Risoe WAsP format is the basis for the wind resource grid data type. Please see the WAsP documentation for more details on this file format.4 In addition to the WAsP format, Openwind has its own binary file format (.WRB) which is covered in Project Design Grid (.WRB) Format.
• Meteorological Mast
  • Wind Frequency Tables. These are also based on a Risoe WAsP format (*.TAB). The TAB file format contains the frequency distribution of wind speeds and directions measured at a meteorological mast and are usually quality-controlled and adjusted to reflect long-term wind frequency distribution. When loaded into Openwind, a TAB file becomes a Met Mast Layer.
  • Met Mast CSV files. This is a simple ASCII, comma-delimited Openwind format. It is output from Windographer or from UL and contains time series meteorological data at one or more heights at a single location.
• Entire Directory (Windnavigator). This option allows users to load an entire directory into Openwind. Openwind searches through the directory and recursively through all sub-directories in search of recognized file types. When it finds a recognized file type, Openwind interprets it as it would above. Users may also drag and drop directories into Openwind.

Users can access all of the above file types from the File menu.