New microengines could provide 10 times longer life than batteries
for cell phones, laptops
*ATLANTA* (November 23, 2004) -- It may be tiny, but a new
microgenerator developed at Georgia Tech can now produce enough power to
run a small electronic device, like a cell phone, and may soon be able
to power a laptop.
David Arnold, Dr. Iulica Zana and Dr. Jin-Woo Park
(From top to bottom) Postdoctoral fellow Dr. Jin-Woo Park, doctoral
candidate David Arnold and postdoctoral fellow Dr. Iulica Zana with
Tech's microgenerator
300 dpi JPG = 1.14 MB <http://www.gatech.edu/upload/pr/ter42134.jpg>
The microgenerator is about 10 millimeters wide, or about the size of a
dime. When coupled with a similarly sized gas-fueled microturbine (or
jet) engine, the system, called a microengine, has the potential to
deliver more energy and last 10 times longer than a conventional battery.
Developed by doctoral candidate David Arnold, postdoctoral fellows Dr.
Iulica Zana and Dr. Jin-Woo Park, and Professor Mark Allen, in the
School of Electrical and Computer Engineering at Georgia Tech, the
microgenerator produces useful amounts of electricity by spinning a
small magnet above a mesh of coils fabricated on a chip. The
microelectromechanical system (MEMS) was developed in close
collaboration with Sauparna Das and Dr. Jeffrey Lang in the Department
of Electrical Engineering and Computer Science at the Massachusetts
Institute of Technology (MIT).
While work has been underway for several years on various microengine
concepts, Georgia Tech's generator has now demonstrated the ability to
produce the wattage necessary to power an electronic device, Arnold said.
"We can now get macro-scale power from a micro-scale device," Arnold added.
This advancement is a key step in microengines someday being
incorporated into products and possibly replacing conventional batteries
in certain electronics.
"This is an important step in the development of MEMS-based micro-power
systems," Allen said.
The device's magnet spins at 100,000 revolutions per minute (rpm), much
faster than the comparatively sluggish 3,000 rpm of an average car
engine. Speed like that is capable of producing 1.1 watts of power, or
enough juice to run a cell phone.
If the project reaches its projected goal, it will eventually produce as
much as 20 to 50 watts, capable of powering a laptop.
The research is part of a larger project funded by the Army Research
Laboratory to create lighter portable power sources to replace the heavy
batteries that currently power a soldier's equipment, such as laptops,
radios, and GPS systems. Researchers at the University of Maryland and
Clark Atlanta University also collaborate on the project.
Georgia Tech microgenerator
The microgenerator produces useful amounts of electricity by spinning a
small magnet above a mesh of coils fabricated on a chip
300 dpi JPG = 1.42 MB <http://www.gatech.edu/upload/pr/tdh42134.jpg>
One of the team's key problems was figuring out how to spin the magnet
fast enough to get useful amounts of power, while keeping the magnet
from breaking apart. High-performance magnets are brittle and easily
broken up by the centrifugal force created by high speeds. To overcome
this problem, the researchers have optimized the magnet dimensions and
encased it in a titanium alloy to increase its strength.
In the lab, the team used an air-powered drill -- similar to what a
dentist would use -- that simulates the spinning of the magnet by the
micro gas turbine (still under development at MIT). Now that initial
tests have been successful, they hope to increase the speeds to what
would be used in an actual microengine to squeeze out more power.
The Georgia Tech/MIT team will present their progress with the project
at the International Conference on Micro Electro Mechanical Systems
(MEMS) in January.
The Georgia Institute of Technology is one of the nation's premiere
research universities. Ranked among /U.S. News & World Report/'s top 10
public universities, Georgia Tech educates more than 16,000 students
every year through its Colleges of Architecture, Computing, Engineering,
Liberal Arts, Management and Sciences. Tech maintains a diverse campus
and is among the nation's top producers of women and African-American
engineers. The Institute offers research opportunities to both
undergraduate and graduate students and is home to more than 100
interdisciplinary units plus the Georgia Tech Research Institute. During
the 2003-2004 academic year, Georgia Tech reached $341.9 million in new
research award funding
[Homestead] Microgenerator to power laptops, eliminate batteries,
tvoivozhd, 01/25/2005