PRIMERO-Light is a simulation program to determine the daylight factor and the expected electricity demand for artificial light in a single room. PRIMERO-Light can be used as stand-alone or as an add-on program for PRIMERO-Energy.

PRIMERO-Light is only available in German.

Due to the 3D input an easy understanding of the spatial geometry is possible. The control input is done through an interactive space view.

Next PRIMERO-Light offers light:

- Sensible defaults for the early planning phase

- Defining zones of light in the room with different requirements

- Selection of main use daily profile and light requirement

- Validated fast light-calculation of daylight factor

- Graphical representation of the daylight factor in plan and in any section

- Variant form with comparison of the daylight factor to optimize the daylight situation 

- Insert calculation of daylight autonomy and the electricity demand for artificial light for a more advanced model of the LEE 2000 / quote or link /

The principle of geometric input PRIMERO-Light is very simple, it follows a cuboid geometry. By drawing correspondingly positioned internal barriers more complex room geometries can be easily displayed.

By the insertion of windows in the walls and the ceiling of the room and the positioning of the inner barriers -horizontal, vertical or inclined- the interior is further defined. Fixed external shading on own space (e.g. overhang) and objects in outer space (neighboring buildings) can be placed.

About the light zones query, the floor plan of the room will determine which lighting requirement should have a point in space. It is possible to define not only the main traffic areas, also non usable spaces.

For several main uses of the space, corresponding standard values ​​for the request to the illumination intensity as well as the connected load of the art lighting system and the use of space-time are assigned.

Simulating PRIMERO-Light takes place on the basis of the hourly weather data sets. So the supply of rooms with natural light, which is offered by the diffused light from outside, and the remaining electricity demand for artificial lighting are determined.

The hourly diffuse radiation can be selected from the existing data sets Hamburg, Frankfurt and Munich in Germany. Weather data from these input values ​​can be generated for any other sites.

The daylight factors are calculated in the room in 85 cm height above the ground in a field of 25 x 25 grids for the overcast sky from the geometry data of the room, the transmittances of the window, the reflectance of the room surfaces and shading objects.


The daylight autonomy describes the proportion of the usage over which the space can be supplied with sufficient daylight.

The daylight autonomy and the resulted electricity demand for artificial lighting are present. The department may issue the respective variants. Documented and viewed calculated results are printed clearly.