Stadtwerke Karlsruhe – Customer Center Kaiserstraße
An interesting device was located on the facade of the Stadtwerke customer center. In a transparent plastic cylinder extending over two floors, there was a rod along its entire length that shone or could shine at various points. Around this rod at different heights were rings of different colors (green, yellow, orange and red) made of light tubes. Some of them glowed, others did not.
In daylight, it was easy to see that this was a thermometer.
The customer center closed on June 30, 2019, and the device was subsequently dismantled.