The door is equipped with a special generator that controls the rotating speed of the door to make it safer. A set of super capacitors stores the generated energy as a buffer and provides a consistent supply for the low energy LED lights in the ceiling. In case the LED lights have used-up all the stored energy, the control unit will switch to the alternative mains supply of the building to ensure the door is illuminated even when the passenger flow is minimal.
LED scales inside the door indicate the amount of energy that is generated – the slower someone passes through the door the less energy is generated. Another LED indicator at the control unit shows when the illumination of the revolving door is powered by human energy, or by the mains supply. The total amount of energy that is generated by the revolving door is accumulated and shown on a large display inside the building.
You might expect the amount of energy saved to me minimal but the company calculated that the door would provide an energy saving of around 4600 kWh per year – a considerable saving compared to a conventional entrance.