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DISCOVERMAGAZINE.COMWe’re in a windowless basement room
on Georgia Tech’s Atlanta campus. A trio
of fresh-faced researchers stand nearby
in white lab coats, watching and smiling.
One holds a keyboard, and another a
piece of red and yellow fabric.
“In our environment, everything is
moving, everything is changing,” Wang
says, still shaking. “It’s all energy, and so
much is wasted.” He wants to do some-
thing about that. For the last decade and
a half, Wang, an electrical engineer and
nanotechnologist, has sought ways to
scavenge energy from the movements of
ordinary life.
His timing couldn’t be better. The
energy problem is big: We need power in
large doses to keep our cities lighted and
cars running, and we need electricity in
small doses — lots of them — to recharge
batteries in our phones, fitness trackers
and tablets. Those demands have a cost.
Last year in the United States, about
two-thirds of the total energy demand
required burning fossil fuels like coal and
natural gas, a process that releases carbon
dioxide and other greenhouse gases into
the atmosphere, where they’re reshaping
the climate.
Renewable power sources, including
sun, wind and water, provided another
17 percent or so of total energy demand.
But harnessing the forces of nature
involves challenges that are formidable
— and currently unsolved. Even the bike
lights and elliptical machines that con-
vert exercise into electricity need a lot of
OOMPH to work.
Instead, Wang is pioneering an engi-
neering effort to generate electricity with
a small oomph. Like from footsteps. Or
raindrops hitting a car. Or the effort
required to press keys on a keyboard.
Or the small vibrations of a shirt, worn
through the day. These ordinary motions,
and others, could charge our devices and
light our homes.
Built into that plastic sphere in Wang’s
hand is a kind of generator that uses
cheap, readily available materials to
THE PLASTIC GIZMO in Zhong Lin Wang’s hand doesn’t
look like tomorrow’s solution to our looming energy crisis.
It’s about the size and shape of a small grapefruit, but
smooth and translucent. As he shakes it, a smaller ball
inside bounces around freely.
“If you’re out of power, you’re out of everything,” says
Wang, speaking in a fierce whisper that demands listeners
lean in. He stands perfectly still, but the shaking makes the
interior ball clatter around like a frustrated piece of popcorn.
In his other hand, Wang holds a small circuit board with
a blinking LED light in the middle. A wire connects the
plastic sphere to the light. The more he shakes, the louder
the clatter, and the faster the white light blinks on and off.