Fascinating piece in the WSJ today about the rise of parasitic power generators: technologies that capture electrical energy that is otherwise a wasted byproduct of everyday human activities, such as walking or exercising. While this has long happened with bike lights, and is emerging in gyms, other examples are legion:
Enviu, a Dutch environmental group, is building a
nightclub in Rotterdam that will have a dance floor that converts
vibrations from all those feet into electricity. One potential design
for the floor involves piezoelectric crystals, which generate a small
electric current when compressed. But Enviu’s 20-by-20-foot floor cost
$260,000 and will generate only enough power to run some lights
embedded in it.
A London design firm called Facility:Innovate has been
developing flooring materials that could ultimately be used to collect
energy from throngs of people walking into busy subway tunnels. In one
design, each step on the floor would push fluid through a microturbine,
Human power may have more practical uses as an energy
source in developing countries or in remote environments where
electricity isn’t available. The U.S. military has spent millions of
dollars in recent years on research into so-called “heel strike
generators” that can be placed in soldiers’ boots and might help reduce
the battery load they have to carry.
Larry Rome, a biology professor at the University of
Pennsylvania, recently launched a company called Lightning Packs that
aims to sell backpacks that generate electricity from the jiggling
motion of walking. In a recent test, his prototype was able to produce
about 15 watts of power from the up-and-down motion of the pack.