Planning a solar farm ====================== Module contributed by Paolo Cavallini - `Faunalia `_ .. note:: This chapter shows how to use several criteria to locate the areas suitable for installing a photovoltaic power station First of all, create an aspect map from DTM: - :menuselection:`GRASS --> r.aspect` [Data type: int; cell size:100] In GRASS, aspect is calculated in degrees, counterclockwise starting from East. To extract only South facing slopes (270 degrees +- 45), we can reclassify it: - :menuselection:`GRASS --> r.reclass` with the following rules:: 225 thru 315 = 1 south * = NULL You can use the text file ``reclass_south.txt`` provided. Note that with these simple text files we can create also very complex reclassifications. We want to build a large farm, so we select only large (> 100 ha) contiguous areas: - :menuselection:`GRASS --> r.reclass.greater` Finally, we convert to a vector: - :menuselection:`GRASS --> r.to.vect` [Feature type: area; Smooth corners: yes] **Exercise for the reader**: repeat the analysis, replacing GRASS commands with analogous from other programs.