In Japan traffic vibrations on road bridges generate energy

The vehicles' transit generate electricity used for lighting purposes

In Japan the “Goshiki-Zakura-Ohashi” bridge over the Arakawa river has been equipped with a series of small generators which convert the micro-vibrations generated by the transit of vehicles into energy used to power the bridge’s night lighting system. Now the Metropolitan Expressway Co., the company managing the construction and maintenance of the road bridges in the Tokyo metropolitan area, has announced a project that envisages to equip all the company’s bridges with a new system capable of generating electricity out of the vehicles’ vibrations.

The system works on the same principle as loudspeakers, though in reverse: as the membrane of a loudspeaker starts vibrating after getting electric energy, so the generators installed on the bridges capture the vibrations of the passing vehicles to generate electricity.

It is an example of renewable energy source that would otherwise go to waste. The project comes out of calculations based on efficiency and cost-effective advantage, at least in the long run, and it envisages the installations of vibro-energy generating systems everywhere in the capital’s metropolitan area. Actually this is a small contribution which, though, alongside the exploitation of solar and wind energy, can eventually help make roads safer, by introducing technologically advanced road sign systems.