Solar Radiation
kWh/m² on every surface, with your neighbours casting the shade
1Where is the building?
Pick the weather station nearest your site. Skip it and London Heathrow is used.
Try:
Then drop your model, or open a sample below
kWh/m² on every surface for a year, a season or a single day, with your neighbours casting the shade.
Rhino .3dm.obj / .fbxIFCNever uploaded — opened in your browser
No model to hand? Open a sample
- 1Pick the location
- 2Load a model or a sample
- 3Run and read the facades
About Solar Radiation·Cumulative kWh/m² on every surface across the year.
What Solar Radiation does
Calculates how much solar energy each surface of your model receives over any time period. Output is a colour-coded heatmap useful for shading design, PV placement, and overheating risk.
- Input:
- .3dm / .obj / .ifc + .epw
- Output:
- Heat map + facade breakdown
- Unit:
- kWh/m²
How it works
Every hour of the EPW's direct and diffuse sun is projected onto each surface, with your own geometry casting the shade. Checked against Radiance.
- Hourly direct and diffuse irradiance from the EPW: no synthetic sky.
- Neighbours, ground and the building itself cast real shadows; nothing is a form factor.
- Runs in your browser; a city-scale mode is there for large models.
How to use it
- Load a model. A .3dm, .obj, .fbx or .ifc with your design and its neighbours, or open a sample. Layers named Context, Site or Ground cast shade and are not measured.
- Pick the weather. The EPW supplies every hour of direct and diffuse sun; without one there is nothing to measure.
- Choose what to measure. By default the whole model is measured, and layers named Context, Site or Ground only cast shade. Use Manage Layers to measure specific surfaces; the choice is remembered for that file.
- Pick a period. Annual, summer, winter, custom range, or a single day.
- Set the grid. The tool picks a cell size from the model and tells you the cell count and rough time before you run. Finer is sharper and slower.
- Run and read the results. The rail on the right says which facades are hot, what the roof carries and what to try; click an orientation or layer to see those cells alone.
Best used for
- Finding which surfaces are worth putting PV on before sizing a system.
- Ranking shading-device options by how much summer gain they actually remove.
- Spotting overheating-prone glazing early in the design.
- Comparing massing options by annual gain on the same facade.
Not a substitute for
- Energy-model inputs for a compliance submission.
- Predicting a specific year's generation — the EPW is a typical year.
- Anything requiring a bankable yield assessment.
Known limits
- Only geometry you load casts shadows: leave out the neighbours and every number reads high.
- Ground and surrounding surfaces are treated as diffuse reflectors at a fixed albedo — a glazed tower opposite will reflect more than this models.
- No spectral or angular glazing behaviour; this is incident radiation on a surface, not transmitted energy.
- Snow, soiling and seasonal vegetation are not modelled.
- Result resolution follows the mesh: a coarse model gives coarse shadows.