Shading Objects

SolarFarmer is built on a full 3D model and shading objects can be added to this model in addition to the terrain data.

You can also define building regions and building models to create buildings to place racks on and act as additional shading elements.

All these may cause shading effects on the PV modules.

  • For 2D calculations:

    • The shading objects and buildings are ignored and not taken into account.

  • For 3D calculations:

    • For fixed-tilt rack sites the shading objects, buildings, and the terrain geometry itself affect both beam and diffuse shading effects.
    • For tracker sites, the shading objects and buildings affect both the beam and diffuse shading effects. The terrain geometry does not currently affect the beam shading, only diffuse.

Shading Objects

There are three ways to add shading objects in SolarFarmer:

  1. Importing pre-defined 3D objects
  2. Creating 3D models
  3. Defining simple boundary-based shading objects

Add Pre-defined 3D Objects

3D objects prepared in other software packages (such as Sketchup) that have been saved in COLLADA (Collaborative Design Activity) *.dae format can be imported into the SolarFarmer workbook and positioned in the site. This is particularly suited to complex objects or objects that you want repeated across the site area.

You can also import 3D models saved from the 3D Model Workshop (.ShadingModel).

  1. Go to the '3D Models' tab in the bottom panel in the Shading objects task.

    a. Click the 'Import' button and select the COLLADA file.

    Import 3D Model

    b. The object will be shown in the 3D Models Library in the bottom panel. Several properties will be shown.

    c. You may add several objects to the library.

  2. Select the object in the library that you wish to add an instance of to the map.

  3. Select the 'Add 3D Shading Object' tool in the map's toolbar (green tree with green '+' symbol highlighted in red below)

    Located 3D Objects Tool

  4. Click on the map to add an instance of that 3D object at the location you click

    a. The map tool reverts to the 'Select' tool \(-\) click and drag the object to exactly where you want it.

  5. Switch the map to 3D mode (the '3D button in the top-middle of the map) to view the objects in 3D.

Tip

Hold down the CTRL keyboard key whilst adding 3D objects to maintain the adding object functionality so you can quickly add multiple objects.

Create 3D Models

SolarFarmer allows you to create and customize a variety of 3D model object types.

The 5 object types currently available are: Box, Cylinder, Wind Turbine, Conical Tree, and Oval Tree.

To create and add a 3D model:

  1. Go to the Shading objects > Shading objects Task screen in SolarFarmer.

  2. Click the 'Create' button in the '3D Models' tab in the bottom panel in the Shading objects task.
    Create 3D Models

  3. Set the type and the specific parameters for the 3D model type.

    • Note that the name of the 3D object is auto-generated, but can be overwritten.
    • The 3D view is interactive; update the parameters and the model in the 3D view will update to reflect your changes. You may need to reset the view, or zoom to extents, if the model no longer fits in the viewing frame.
    • The colour of the object is used in the 2D and 3D map views. The colour does not affect the shading or albedo qualities of the object; it is purely for visual purposes only.
    Box
    Cylinder
    Wind Turbine
    Conical Tree
    Oval Tree

  4. Click 'Create model and add to library' and the model will be added to the Library section of the '3D Models' tab.

  5. Add the created 3D objects using the 'Add 3D Shading Object' tool in the map's toolbar:

    Any 3D objects on the map will be listed on the '3D models on the map' section of the '3D Models' tab with its name, location and reference library object.

    3D Models On The Map

Importing and exporting 3D models

From the 3D Model Workshop you can export the parameters for the currently selected 3D model type to a .ShadingModel file. These files can then be imported into other SolarFarmer workbooks.

To do this, click the 'Export...' button in the 3D Model Workshop, and save the file to your computer.

Click the 'Import...' button to import previously saved 3D model parameters in the 3D Model Workshop. Just be aware that importing 3D model parameters in the 3D Model Workshop will overwrite the current model parameters for that model type. Do this if you're interested in subsequently modifying the parameters.

If you're just interested in using previously saved 3D model parameters, use the 'Import...' button in the '3D Models' tab which will add the 3D model directly to the library.

Editing 3D models

Once created and added to the 3D library, you can subsequently edit the parameters of a 3D model by selecting it in the library and clicking the 'Edit...' button. This will open the 3D Model Workshop with the parameters of the selected 3D model type.
Edit 3D Models

Change the parameter values, even change the type of the 3D model (a tree can become a wind turbine should you wish!). Then click the 'Update model in the library' button to update the model.

Any 3D models on the map that are of the type you've edited will be updated to reflect the changes you've made.

Note that editing is only available for 3D models that have been created using the 3D Model Workshop. 3D models that have been imported from COLLADA files cannot be edited in this way.

Selecting 3D models on the map

Once you have added several 3D model instances on the map, you can either select them by clicking on them individually, or use the 'Select 3D models in a polygon' tool in the map's toolbar to select multiple 3D models at once.
Select 3D models in a polygon
Once multiple objects are selected, you can move them as a group or choose to delete them by pressing the 'Delete' keyboard key.

Define Simple Boundary-Based Shading Objects

If you don't have access to a 3D modelling package, or the 3D model types don't work for you, you can create a quick 3D volume to approximate a forest, hedge or building by adding a shading region.

  1. Click on the 'Shading region' button in the map toolbar (green polygon with '+' symbol highlighted in purple below).

    Shading Regions Button

  2. Click on the map to add points to form a polygon. Finish the polygon by clicking on the first point you clicked.

  3. A new shading region object is added to the map and also to the table in the 'Shading Region Objects' table in the bottom panel.

  4. Set the height of the shading region (height above the terrain) and the type:

    a. 'Follows terrain' means that the height of the volume will be the same above each point. Useful for forests or hedges whose height you want to follow the terrain.

    b. 'Flat top' means that the 3D volume will have a horizontal top face. Useful for modelling simple flat-topped buildings.

  5. Again, switch the map to 3D mode to see the 3D volume.

Tip

You can also double-click on the last point to quickly finish a polygon.

Tip

You can adjust the height of the shading regions whilst in 3D mode to fine-tune the height of the shading regions.