The software calculates the illumination at each time step and displays the average value on an annual basis.
It is also possible to visualize the levels available at each hour of the year

Dynamic simulations

Dynamic simulations are run with the Radiance three-phase method. Those simulations are based on hourly calculations and take into account both diffuse and direct components. This type of calculation is particularly suited for rooms equipped with automated shading devices or electrochromic glazings.

Based on hourly illuminances, dynamic simulations allow to calculate sDA (Spatial Daylight Autonomy)  and UDI (Useful Daylight Illuminance).


Spatial Daylight Autonomy (sDA)

The sDA is defined as percentage of the task area that meets a minimum daylight illuminance level for a given fraction of operating hours per year, i.e., that meets a defined daylight autonomy level.

Useful Daylight Illuminance (UDI)

UDI is the annual occurrence of daylight illuminances across the workplane within a given range. This range was defined to encompass “useful illuminances for occupants” from a comprehensive review of occupant’s behavior with artificial lighting, dimming and blinds.

Temporal maps

The software allows to display, on a single diagram, the average value of the illuminance at each hour of the year, or the state of the sun protection at each time step.


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Useful Daylight Illuminance (UDI)