The energy you expend at the gym, on the nightclub dancefloor, and now, pushing a revolving door are sources for capturing electrical energy that is reusable.
Fluxxlab, a design firm aiming to convert small amounts of human energy into electricity has created The Revolution Door and Powerslide, two prototype devices with mechanical/electrical systems that harnesses human motion and redistribute it as electricity.
According to the site, "the Revolution Door will directly communicate a single person's contribution to an energy cycle possible through the metabolic relationship between people, technology, and architecture." It's not clear when the doors will be put into practical use, but the impressive imagery doesn't indicate that it's any time soon:
Beating the design firm to the punch, however, a company based in Amsterdam has already developed an energy generating revolving door that is in use at the newly renovated Driebergen-Zeist railway station in the Netherlands.
The Boon Edam revolving door utilizes super capacitors that store the generated energy as a buffer and provides a consistent supply for the low energy LED lights in the ceiling that illuminate a cafe within. Someone going through the door can actually see the technology in the ceiling as it's made of clear safety glass (see image below). If the stored energy runs out, a control unit switches to the alternative mains supply of the building, ensuring that the door is illuminated at all times. According to the firm, the door will save around 4600 kWh per year in energy, which is about enough to power about five average American households for a month.
The bigger picture
There are countless projects worldwide that involve harnessing human movement to generate electricity for localized power consumption and to even send it back to the main grid. While not present in the revolving doors discussed, the chief technology used for this energy conversion is piezoelectricity, essentially a technique for converting kinetic energy into electrical.
Researchers, designers, and ‘green’ innovators are experimenting with piezoelectric systems across a wide variety of applications that generally involve high-traffic, crowded facilities ideal for generating enough power for worthwhile results. But small amounts of human energy, like the kind generated by a tapping a finger can also be scavenged, and it may also find potential uses. In any case, expect an intelligently powered future that'll continually broaden the meaning of alternative energy.