illuminance levels reaching between 150 lux on
cloudy days and more than 800 lux on clear, sunny
days. In the evening it is supplemented with artificial
light with colour temperatures tuneable between
2700K and 6500K. During normal use, the average
horizontal illuminance in the assembly hall is
500-600 lux, while for television broadcasting the
illuminance can be increased to more than 1000 lux.
Linear LED profiles are arranged radially around
the daylight cones and tubes like the blades of a
turbine, tilted towards their centre by 30 degrees.
This achieves the optimal balance of cylinder, cone
and luminous ceiling illumination.
The daylighting solution, together with the
preservation of the original high-quality building
structure and an energy modernisation programme,
brought about a 40 per cent energy saving. And the
once windowless and introverted hall now has a
direct visual connection with the outside.
Above: conical openings that allow direct views to the sky reach
down to the luminous ceiling where they are closed with clear panes
Left: the 12 large circular skylights and 36 smaller ones are inserted
flush with the flat roof. Electrochromic glazing controls light ingress