Where infrared.city fits
3,204,804 simulations run on Infrared Core (as of 29 Oct 2026).
infrared.city runs 12 models from one engine, Infrared Core, among them wind, wind comfort, sun, daylight, radiant heat and felt heat (UTCI). It works on real 3D building and terrain meshes, in a browser app, through an API and SDK, and in plugins for Grasshopper, QGIS and ArcGIS. Felt heat for 1 km² takes about 5 s once the geometry is uploaded, and 400 km² took 44 s as four 100 km² runs in parallel. Run times are not like for like across tools: area, grid, simulated hours and physics differ. Sun, sky and radiant heat come from ray tracing. Wind comes from an AI model trained on CFD results, not from a CFD run for each request.
- You compare many design options for a block, a district or a whole city.
- You need wind comfort, sun, daylight and felt heat for the same model from one engine.
- You run studies from your own tools through the API, or in Grasshopper, QGIS or ArcGIS, with nothing to install.
- You need an hourly city layer for a digital twin.
Use both
The two tools do different jobs. infrared.city is built for many options over large areas. ENVI-met resolves the full time-dependent microclimate physics of one site and takes hours to days per run.
Screen the options in infrared.city. Then run the one chosen design in ENVI-met when the project needs the full physics. Most teams use infrared.city to decide, and validate only the cases that need it.
Facts side by side
| infrared.city | ENVI-met | |
|---|---|---|
| Method | Ray tracing for sun, sky and radiant heat; wind from an AI model trained on CFD results (no CFD run per request) | Full 3D microclimate physics over time, on cells of typically 1 to 10 m, time step 1 to 5 s |
| Run time | About 5 s for 1 km² of felt heat (UTCI, 08 to 18 h, geometry uploaded, measured); 400 km² in 44 s (four runs in parallel) | About 65 h per simulated day for a 0.06 km² block at 1 m (version 5.9, one published run on a 24-core workstation) |
| Outputs | 12 models, among them wind, wind comfort, sun, daylight, radiant heat and felt heat (UTCI) | Wind, air temperature, humidity and radiation in 3D; comfort indices PET and UTCI |
| Runs as | Cloud: browser app, API and SDK, plugins | Windows desktop, 64 bit |
| Licence and pricing | Tokens: free start with 900 tokens, plans from €240 a year | Subscription; no public prices |
The run times are not like for like: area, grid, simulated hours and physics differ. ENVI-met computes the full microclimate over time; infrared.city computes felt heat from ray-traced radiation and an AI wind model.
The infrared.city values repeat the full comparison. Each value for ENVI-met comes from the sources below.
Sources
- ENVI-met help centre: model grid and time step , accessed 24 Oct 2026.
- ENVI-met help centre: thermal comfort (PET, UTCI) , accessed 30 Oct 2026.
- ENVI-met pricing , accessed 24 Oct 2026.
- Sinsel et al. (2026), Atmospheric Environment: X 31, 100479 , accessed 24 Oct 2026.