Science August 2014 | Page 4

Turbines are getting
larger as well as smaller

TECHNOLOGY UNCOVERED
Powering gadgets

MOVEMENT

HEAT

4. BODY’S ENERGY

IMAGE © JOHN ROGERS ILLINOIS UNIVERSITY

The human body, even at rest, is
constantly producing about 100
watts of power – and much of this energy
is lost as heat. This led a 15-year-old
named Ann Makosinski from Victoria in
British Columbia, Canada, to develop an
LED torch, called the ‘Hollow Flashlight’,
which is powered by the heat in your
hand. You just pick it up and the torch
comes on. You act as the battery.
The torch uses Peltier tiles, which
siphon off some of the energy from the
heat flow between two materials of
differing temperatures. The torch is
hollow and allows air to flow through it, so
when you pick it up there is a temperature
difference between the outside of the
torch, which is warmed by the palm of your
hand, and the inside – which isn’t.
The heat produced by your hand is
enough to create light at a level of about
24 lumens. Although this is a lot less than
a typical torch (which gives off about 900
to 1,200 lumens) it is still enough to see
by and Makosinski hopes it could help
people in developing countries who can
currently only study in daylight as they
don’t have access to

Peizoelectricity can be used to harness the movement
of our internal organs and produce power

3. ORGAN POWERED

a power supply.

Turbines just 1.8mm across could be used to coat our
smartphones, generating energy to charge them

5. MICRO WINDMILLS
The future of wind turbines may be
a lot smaller. So small that 10 of
them could fit on a grain of rice, in fact. Dr
Smitha Rao and Professor JC Chiao,
researchers at the University of Texas at
Arlington, in the US, have designed ‘micro
windmills’ just 1.8mm wide, which could
be used to coat our gadgets. Chiao
imagines this to take the form of a sleeve
that could be placed over your
smartphone to recharge it – you would
then simply wave the phone in the air.
While it’s currently no replacement for a
mains socket, a few minutes of waving
would be enough to send a message if
you’re stranded in a remote area.
The nickel alloy used can stand up to
strong gusts, despite using components
a fraction of the width of a human hair.
The team have also come up with a
way of manufacturing the windmills
using electroplating techniques, so they
are easy and inexpensive to make. So
you could coat your house with them as
an alternative to a full-sized turbine.

Jamie Middleton
IMAGE © ANN MAKOSINKI

Imagine implanting a small
rechargeable battery inside a living
body, which is powered by the natural
movement of organs such as the heart or
lungs as they go about their daily
business. Engineers at the University of
Illinois, in the US, have done exactly that.
The stamp-sized flexible battery is made
of lead zirconate titanate embedded in
ultrathin plastic, and draws energy from
the organs’ movements. It does so via
piezoelectricity – the charge that builds up
in certain materials when stressed.
The battery has been developed as
an alternative to those used in medical
devices such as heart-rate monitors,
pacemakers and neural stimulators. If
long-term studies prove successful, these
could negate the need for patients to
undergo invasive surgery to replace
batteries every few years. This tech, the
team claim, could in the future store
energy generated from leg and arm
muscles, and even skin cells, meaning it
could be used to power external gadgets.

IMAGE © UNIVERSITY OF TEXAS - UTA

WIND

Science writer
+ Jamie is an editor and writer with
a keen interest in technology and

ABOVE: Inventor Ann Makosinski won the age 15-16
category at Google’s global science fair

innovation. @jamiemid

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