They really do come up with the wackiest ideas over there in Japan:
Heavy foot traffic at busy subway stations could soon be widely used to power station lighting and other electrical equipment thanks to technology currently being trialled in Tokyo.
In a small-scale experiment at Tokyo Station, one of the city's busiest subway stops, so-called hatsudenyuka floors were installed at station gates, hallways and staircases.
The technology features elements capable of generating piezoelectricity, which are embedded in 0.4mm flooring tiles and covered by a mat. The piezo elements convert the pressure and vibration of commuter footsteps into electricity, which is used to power the station's lights.
The experiment is being run by subway operator East Japan Railway Co, Tokyo's Keio University and public research body New Energy and Industrial Technology Development Organization.
The trial, which started in 2006, was put on hold in March to analyse data, and early indications are that the energy harvesting system could be rolled out more widely. East Railway said it now hopes to eventually use the flooring as a clean source of supplementary power for other station technologies such as automatic ticket barriers and display panels.
This idea has actually been wafting around for some time. A British firm has been noodling over a system that would employ a "matrix of hydraulic compression pads" under sidewalks and stairs to generate electricity from foot traffic—in theory you could use the energy created by pedestrians stomping around to keep nearby lights running. Some entrepreneurs have even pondered whether you could fabricate a similar system for roads, converting truck traffic into electricity. But it's unclear whether drumming up power this way is even remotely cost-effective, and it always seemed like a totally fanciful idea. Apparently, though, Japan's taking the notion quite seriously.
(Flickr photo credit: emptybits)
--Bradford Plumer