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Solar Irradiation - [source code]

Cumulative incident solar energy per point in kWh/m² — beam plus isotropic sky plus ground reflection. An interactive preview, not a Radiance simulation.

Input

Name Nickname Description Type
Context C Shading geometry: buildings, terrain, canopies. Geometry
Points P Analysis points. Point
Normals N Per-point surface normals. Without them every point is treated as HORIZONTAL, which is right for a ground grid and badly wrong for a facade. Vector
Weather W Weather record from Download Weather or Open Weather. Both the sun's position and the direct/diffuse irradiance for each hour come from this one file. Generic Data
HOY H Hours of the year to accumulate [1-8760] — wire the Hour Of Year component to name a date and time. Left empty, every DAYLIGHT hour of the year is accumulated, which is the annual total. Integer
Timestep T Sun samples per hour. 1 is hourly; 10 gives a 6-minute step, which resolves the shadow edge far better (docs/SUN_ANALYSIS.md). The irradiance is still the file's HOURLY value — a finer step refines WHERE the beam lands, not the weather itself. Integer
Sky View SVF Optional sky view fraction per point, from Sky Exposure. Without it the sky is treated as fully open, which overstates diffuse in any real street. Number
Ground Reflectance GR Albedo for the ground-reflected term. Number
Offset O Distance to lift each point off its surface before tracing. Number
North Nth Counter-clockwise degrees from the model's +Y axis to true north (Ladybug's convention). The sun is rotated, not the model. Number
Canopy Cn Optional canopy layers from the Canopy component. Vegetation here attenuates the BEAM only — the isotropic sky term is unaffected, because a canopy that dims the sun also blocks sky, and the sky view fraction already accounts for it if you measured SVF with the canopy in place. Generic Data

Output

Name Nickname Description Type
Total T Total incident irradiation, kWh/m². Number
Direct Dir Beam component, kWh/m². Number
Diffuse Dif Sky diffuse component, kWh/m². Number
Reflected Ref Ground-reflected component, kWh/m². Number
Colors Col Colour ramp over the total. Colour
Report R Totals, rays and the assumptions used. Text