An energy-generating revolving door installed at Driebergen-Zeist railway station in the Netherlands is the latest experiment in eco-building. Dutch company Royal Boon Edam Group Holdings designed the manual door to match the newly refurbished station’s sustainable technology theme, while keeping in mind that the station—converted into a multifunctional area featuring restaurants and a tourist information and visitor center—holds 8,500 commuters at capacity.
The revolving door is equipped with a special generator that is driven by human kinetic energy. The generator 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.
The idea appears novel, but the amounts of electricity potentially generated and saved are small—likely much less than the savings of 4,600 kWh Boon Edam calculated per year for the door when compared to a conventional sliding entrance door. The door does, however, offer users the experience of feeling useful. It is outfitted with LED scales inside the door to indicate the amount of energy generated.When passing through the door at a slow speed, the scale will light up in the red or orange zone, whereas a normal or fast pace pushes the scale into the green zone.
Another LED indicator at the control unit shows when the illumination of the revolving door is powered by human energy, or by the main supply. And the total amount of energy generated from the revolving door is shown on a large display inside the building. The door even features “Human Powered Energy” stickers; these are “to make users aware of their contribution to this green building,” Boon said.