7PV areas

A ground-mounted installation is entered as one outline of the whole mounting area; individual module tables are not traced, and the area counts as fully covered. If orientation, tilt or slope position differ, the installation is split into several PV areas. Per simulation, 3 areas are possible in the Free plan and 50 in the Pro plan (Ch. 3).

7.1 Entering

1. In the "PV Areas" menu, choose "New PV area" and select the system type (Ch. 7.2).
2. Draw the area or upload it as a KML file. All corner points must lie within the project area.
3. In the area's object card, enter orientation and heights (sections 7.3 and 7.4) and select the module type (Ch. 8).
4. For ground mounts, check the terrain under "Terrain and cross tilt" (sections 7.5 and 7.6).

For "Roof Parallel" and "Facade", the dimensions can be entered in the blue drawing banner instead of clicking: "Length" and "Direction" of the top edge or the facade line, for "Roof Parallel" then the "Depth" to the bottom edge; this gives an exact rectangle. Typing a number jumps into the first field, Tab switches the field, Enter places the point, an empty field takes the value at the mouse; the direction is in degrees from north, clockwise (90 = east). The same input is available when drawing obstacles (Ch. 10.1).

KML import. Each polygon in the file becomes a separate area. Polygons with holes are rejected; cut-outs are created as excluded areas (Ch. 7.7). Elevation values in the file can be used: for ground mounts as the terrain elevation of the corner points (the area then lies on a best-fit plane), for roof installations either as absolute roof height or as terrain elevation.

7.2 System types

The type is chosen when the area is created and cannot be changed afterwards.

PV areas do not occlude each other in the calculation. A PV area in front that is meant to block the view is additionally entered as an obstacle (Ch. 10.1).

7.3 Orientation and mounting

The azimuth is the compass direction the modules face (0° north, 90° east, 180° south, 270° west); the tilt is their angle to the horizontal. For "Roof Parallel" and "Facade", the azimuth is calculated from the drawing; "Swap Top/Bottom Edges" and "Swap reflecting side" turn it by 180°.

Dual orientation (east-west). In east-west installations, the module rows face opposite directions in pairs. The "Dual Orientation" checkbox adds "Azimuth 2", which always lies 180° opposite; the tilt applies to both. Two areas with the full outline are calculated, one per direction. The illuminance is therefore on the safe side; luminance and glare times are not affected. In the report and for the plan, the area counts once. Mutual shading of the two rows of a table is not calculated.

Tracked ground mounts (trackers) (Pro). Under "Mounting Type", "Tracking system (single-axis tracker)" selects the single-axis tracking model (tracker):

All tracking parameters are required; the simulation does not insert any values. If one is missing, the to-do list reports it and the simulation does not start: "Tracker axis orientation missing", "Tracker angle range missing", "Tracker axis tilt missing or outside ±45°", "Tracker: backtracking not set", "Tracker: GCR missing", "Tracker: rest angle missing". "GCR" and "Rest Angle" are only needed when "Backtracking" is switched on. When switching to tracker, the app fills the fields visibly with the initial values of the table; a new tracker area therefore has no open items. For saved areas that lack a value, the to-do still appears.

The simulation calculates the rotation angle for every time step (default 1 minute) from the sun position (pvlib). The twelve monthly curves under "Tracking Logic" serve only for checking and for the report. Stow, fault and special positions required by the position paper can be calculated as a fixed variant with the set angle as tilt (Ch. 13).

7.4 Top and bottom edge

The top edge must lie above the bottom edge (for "Roof Parallel", equal heights are allowed). For "Roof Parallel", tilt and edge heights are linked: tan(tilt) = (height of top edge − height of bottom edge) / horizontal distance between the edges. One of the three values is determined from the other two with "Auto-Calculate". For roof installations, a roof height of 0 counts as not entered.

7.5 Terrain under the area

Only ground mounts have a terrain menu ("Terrain and cross tilt"). Step 1 defines where the area lies in space:

With "Calculate GL automatically", the elevations are fetched again after every change to the area. If an elevation source does not respond, the values come from the next one, and the to-do list reports this. The elevation map in step 1 shows the area the simulation calculates with. Where the elevations come from is described in Ch. 6.

7.6 Cross tilt

The cross tilt is the tilt of the modules along the table axis, i.e. across their orientation. It arises when a table stands across a slope, and it turns the reflection direction. Without cross tilt, the modules are level across the table axis, even on sloped terrain. Values from −45° to 45° are allowed. A value outside is not limited in the object card or the cross-tilt menu but rejected with the message "The cross tilt must be between −45° and 45°."; the previous value remains. If the terrain gives more than 45° for a new zone, the editor reports "The terrain gives …° in this zone. Allowed is −45° to 45°; please enter the value." and inserts the base value of the area. When the zones are derived from the terrain again, all values remain unchanged as soon as one zone lies outside ("… zones are outside ±45° according to the terrain. The values remain unchanged.").

Azimuth, tilt and cross tilt give the effective azimuth and effective tilt, for example 180°, 30° and +10° → 196.7° and 31.5°. Editor, pre-analysis, simulation and report use the same calculation.

Ground mount. Step 2 ("Account for cross tilt") evaluates the terrain under the area and adopts the median as long as "Calculate cross tilt automatically" is switched on. Step 3 ("Zones", setting "Differentiated") divides the area into zones with their own values, automatically from the terrain or drawn by hand; this requires an elevation grid and a terrain model in the project that fully covers the area. The simulation then splits the area into sub-areas, each with its own orientation; in the result it remains one installation.

Tracker. Here the cross tilt is the tilt of the rotation axis, from −45° to 45°; positive means the axis slopes down in the axis direction. A value outside is rejected on entry with the message "The axis tilt must be between −45° and 45°."; the previous value remains. If the terrain gives more than 45° along the axis, the value is adopted and reported ("The terrain gives …° along the axis. Allowed is −45° to 45°; the simulation stays blocked until the value fits."); the to-do list shows "Tracker axis tilt missing or outside ±45°", and the simulation only starts with a value in the permitted range. There are no zones.

Roof Mounted. The cross tilt is entered directly in the object card.

7.7 Excluded areas

Spots without modules, such as paths, roof windows or ventilation units, are cut out of the PV areas as excluded areas (Ch. 7.7).

Points to note

• Outline and orientation are independent. The module orientation comes from azimuth, tilt and cross tilt, not from the drawn shape. A correct outline says nothing about a correct orientation (Ch. V.2).
• Facades: The drawing direction determines the reflecting side; the orange marking shows it.
• Azimuth changed: The cross tilt applies across the orientation. With automatic calculation, the median and zones are determined again; for manual values, the to-do list reports that they must be set again.