This report measures the near shading of the roof: parapets, chimneys, lift overruns, HVAC units, drawn neighbouring buildings and the shadows module rows cast on one another. The measurement comes from the ray tracing engine the application uses everywhere — the same engine that draws the colours on screen.
2 · Shading plan by module
The numbers inside the modules are the module numbers. Entries such as "#12, #48" in §3 are read directly from this plan; those modules are also marked with a bold outline . If a module is too small to read on the plan its number is omitted — the 20 worst modules are labelled even then. The dashed blue line is the roof footprint.
3 · Most shaded modules
#
Module
Location
Annual shading
1
#1471
Active roof · face 2
10.24%
2
#1475
Active roof · face 2
10.02%
3
#1467
Active roof · face 2
9.82%
4
#1476
Active roof · face 2
9.62%
5
#1474
Active roof · face 2
9.57%
6
#1470
Active roof · face 2
9.40%
7
#1428
Active roof · face 2
9.32%
8
#1472
Active roof · face 2
9.30%
9
#1466
Active roof · face 2
9.29%
10
#1420
Active roof · face 2
9.23%
11
#1473
Active roof · face 2
8.96%
12
#1412
Active roof · face 2
8.94%
13
#1418
Active roof · face 2
8.93%
14
#1482
Active roof · face 2
8.91%
15
#1462
Active roof · face 2
8.90%
16
#1464
Active roof · face 2
8.63%
17
#1424
Active roof · face 2
8.62%
18
#1460
Active roof · face 2
8.61%
19
#1461
Active roof · face 2
8.59%
20
#1479
Active roof · face 2
8.55%
These modules are marked with a bold outline in the §2 plan; the numbers match those on the plan exactly. Location column shows which roof and which face the module is on.
4 · Shading distribution by month and hour
Run the energy simulation first to obtain the month × hour matrix.
5 · Critical day profiles
Day
Daylight
Mean shading
Peak
Shade-free duration
21 December (winter solstice · worst)
08:10–16:50
12.55%
25.90% · 10:50
20 min
21 June (summer solstice · best)
05:20–19:40
0.04%
1.98% · 05:20
14 h 0 min
Annual average (12 representative days, one per month)
11 h 23 min
2.69%
25.28% · December
7 h 53 min
The two days on the chart are the extremes: 21 December is the worst day of the year (lowest sun, longest shadows) and 21 June the best . Every other day falls between these two curves.
The annual average row is a measurement, not an estimate: the 15th of each month was measured separately at 30-minute steps and the 12 days averaged. Peak column in this row is not an average but the highest instantaneous value across the 12 days , with the month it occurred in noted.
Shade-free duration, no module is the uninterrupted period in which no module is shaded at all — not the period in which the roof average is zero. If a single module is shaded, that minute does not count as shade-free. Minutes when the sun is behind the collector plane are not counted as shading and are excluded from the average: with no beam on the plane, the shading ratio is undefined. On hip and pyramid roofs this period is long.
The dashed line is the measured annual shading loss (0.92%). It is not in the same units as the curves: the curves show the shaded module share at that minute, while the dashed line shows the irradiance-weighted loss over the whole year.
6 · Obstacle inventory and shading capacity
The bar length is proportional to height × frontal width — a rough indicator of how much shade an obstacle could produce , not a measured loss. The measured loss is in §1 and §3. This chart shows which obstacle is most worth removing or not raising: tall and wide obstacles cost more than low but long ones.
The parapet is a special case: it cannot be removed, but moving the module row away from it (edge setback) yields a direct gain. The effect of the edge setback is far greater on the north side than on the south.
7 · Electrical shading component
The energy simulation is required for the electrical component.
8 · Method and limitations
Topic
Status
Beam shading
Ray tracing · sampled over the module area
Shading sources
Parapets, obstacles, neighbouring buildings, module rows — all from the 3D geometry
Rear side (sun behind the plane)
Not counted as shading — incident beam is zero
Day profile sample set
samplesEnergy · 6 points per module
Modules measured
4,446 (all — no subsampling)
Distant horizon shading
NOT INCLUDED
Undrawn neighbouring structure
Not modelled — must be verified by a site visit
Snow accumulation and soiling pattern
Not modelled
This report is a design and feasibility output. It is the user's responsibility to ensure every shading source on the roof has been drawn; each undrawn chimney, HVAC unit or neighbouring building makes the shading loss appear lower than it is.
solarsimpro Rooftop · shading engine (parapet and obstacle ray tracing + diffuse sky model) · PR as defined in IEC 61724-1 · reference values from PVGIS v5.3 SARAH3. This report is intended for pre-feasibility purposes.
