Thermopiles in headband power wireless EEG sensor and 2.4 GHz transmitter
This is the IMEC press release from their web site, thought you would
find it of interest. I find the power source of the most interest
myself. There are pictures and video at the link of the IMEC device.
Personally I would not use a device with 2.4 GHz strapped to my
"16-10-2007 - Leuven, Belgium -- IMEC has developed a 2-channel wireless EEG
(electroencephalography or monitoring of brain waves) system powered by a
thermo-electric generator. It uses the body heat dissipated naturally from
the forehead. The wearable EEG system operates completely autonomous and
maintenance-free with no need to change or recharge the batteries. This is a
major advantage for body-worn sensors, a key theme in the Human++ program
within the Holst Centre.
The entire system is wearable and integrated into a headband. The small size,
low power consumption of only 0.8mW and autonomous operation increase the
patient's autonomy and quality of life. Potential applications are detection
of imbalance between the two halves of the brain, detection of certain kinds
of brain trauma and monitoring of brain activity.
The EEG system uses IMEC's proprietary ultra-low power biopotential readout
ASIC to extract high-quality EEG signals with micro-power consumption. A
low-power digital signal-processing block encodes the extracted EEG data
which is sent to a PC via a 2.4GHz wireless radio. The whole system consumes
The thermoelectric generator is mounted on the forehead and converts the heat
flow between the skin and air into electrical power. The generator is
composed of 10 thermoelectric units interconnected in a flexible way. At room
temperature, the generated power is about 2-2.5mW or 0.03mW/cm2 which is the
theoretical limit of power generation on human skin. Higher power generation
would cause an uncomfortable sense of cold. The EEG system is operational in
less than one minute after switching on the device.
Future research targets further reduction of the power consumption of the
different system components including the radio and processor. Also, a
semiconductor process for manufacturing thermopiles is under development.
This will allow a significant reduction of the production cost.
The system is a tangible demonstrator of the Human++ program researching
healthcare, lifestyle and sport applications of body area networks.
Interested parties can get more insight in this research or license the
underlying technologies through membership of the program."
Source: IMEC Press Release.
This one is a bit speculative, but Coal Mines do have large
"Inventor Louis Michaud has formed a company called AVEtec Energy
and obtained patents, and has partnered up with the University of
Western Ontario's wind-tunnel lab to study small prototypes and do
computer simulations of his "vortex engine" process. Heat rises
when you've got a certain temperature differential, and as it rises
it swirls -- kind of the reverse of what you see when water goes
down a drain. AVEtec's pitch might raise eyebrows, but many are
taking it seriously..."
Break via Keelynet.
From thin air: Harvesting or scavenging power for remote-sensor applications
examination of design challenges and terminology surrounding
wireless, low-power-sensor applications."
"...The NanoPower Forum
pulled together a range of topics that, at first glance, do not
appear to relate readily to one another. However, the topics jigsaw
together to form a tightly coupled study of certain low-power
applications. In all examples, the design goal was to implement a
remote function with no signal or power leads connecting the
function's remote location and the rest of the system.
Key among the presentation topics was energy harvesting by various
means, including piezoelectric devices, thermopiles, and
magnetoelectric devices. In many presentations, the energy these
devices made available powered sensors or autonomous communications
nodes, often both acting in concert. The applications for such
devices cover a noteworthy range, including human-body implants,
industrial-equipment monitoring, and sensor networks for commercial
Israelsohn, Contributing Technical Editor -- EDN Magazine,
Vibrations good for harvesting electricity
"By converting vibrations into usable power, researchers are enabling
the battery-free operation of ultra-low-power wireless devices for
everything from medical implants to that black-box under the seat of
new automobiles. If a sensor is needed but it is inconvenient to
supply power--from the inside of a jet engine to the heart's aorta
valve, for example--energy harvesters are being designed to convert
environmental gradients into usable electrical power...
The IMEC vibration harvester uses a
micron-sized cantilever with a carefully calculated mass on its
free-end that oscillates in the presence of vibrations. The
cantilever's fixed end is embedded in a piezoelectric capacitor
formed from two metal electrodes separated by the piezoelectric
dielectric called PZT (Lead Zirconate Titanate). As the cantilever
oscillates, the tiny mass on its end causes the piezoelectric layer
to be alternatively stretched and compressed by about 180
nanometers. Each cycle causes an alternating current (AC) to be
generated in the circuit it powers, producing a maximum of 40
microwatts at the cantilever's resonance frequency of 1.8 kHz..."
Source: E.E.Times, by
R. Colin Johnson, via Automotive Design
Good vibes power tiny generator
A tiny generator powered by natural vibrations could soon be
helping keep heart pacemakers working.
The generator's creators say their technology is up to 10 times
more efficient than similar devices...
The tiny device, which is less than one cubic centimeter in size,
uses vibrations in the world around it to make magnets on a
cantilever at the heart of the device wobble to generate power...
Work on the project was funded by the EU as part of the 14.3m
euros (£9.67m) Vibration
Energy Scavenging (Vibes) project that is looking at how to use
environmental vibrations to generate power.
Source: B.B.C. News, via Keelynet.
Perpetuum - Energy harvesters power low-cost industrial wireless system
Energy harvesters are powering the world's first low-cost
industrial wireless condition monitoring system. The PMG17-100
energy harvesting microgenerator, developed by Perpetuum, converts
machine and plant vibration into useful electricity, enabling
wireless sensors to transmit large amounts of critical
data. Perpetuum's microgenerators can be used to power condition
monitoring systems enabling end-users to continually monitor plant
and equipment allowing them to make significant cost savings, says
the company [Perpetuum].
operates on vibration from plant or machinery running on mains
frequency at 50Hz. It transforms the kinetic energy of vibration
into an electrical current, producing ample power, for a wireless
transmitter to send 6 Kbytes of data (i.e. a vibration spectrum),
every few minutes, or smaller amounts of data several times a
second. Installation is easy, efficient and virtually instantaneous:
it is simply placed on the piece of equipment without the need for a
timely and costly plant shut-down...
Power Components: ICs address alternative energy sources
Imagine a cell phone that offers endless standby power, or an MP3
player that never needs recharging. That is the promise of powering
portable consumer electronics devices off renewable power
sources. By harvesting power from external sources such as solar or
micro fuel cells, systems can tap into what is for all practical
purposes an infinite source of energy...
In March, TI introduced a step-up
converter designed to help designers cost-effectively use the
nonstandard voltages from alternative power sources to recharge the
core lithium-ion battery in a portable electronic device. The TPS61200
integrates a 1.5-amp switch and supports input voltages from 0.3 to
5.5 V. It can manage power down to 0 V if the undervoltage lockout
pin is connected directly to the output voltage. It supports an
extremely low, 0.5-V startup in any load condition and still
maintains efficiency of up to 90 percent...
Source: E.E. Times, by John H. Mayer, via Embedded Systems.
Researchers apply energy harvesting to portable devices
MANHASSET, N.Y. The move to provide supplemental energy sources
for batteries in portable devices is accelerating as more mobile
phones, MP3 players, laptops and wireless devices use some form of
Source: E.E. Times,
by Nicolas Mokhoff.
Nano, MEMS are advancing energy harvesting technology
ROSEMOUNT, Ill. Using nanotechnology and MEMS technology in
energy harvesting applications is a work in progress that
nevertheless shows huge potential, experts said.
Progress was in evidence at this week's Sensors Expo here,
including a session on using nanotechnology and MEMS in energy
harvesting applications. Panelists said companies like EaglePicher,
Tadiran and Varta are capitalizing on existing lithium technologies
to offer micro batteries for energy harvesting applications...
Source: E.E. Times, by Nicolas Mokhoff.
Vibrations good for harvesting electricity
EINDHOVEN, Netherlands -- By converting vibrations into usable
power, researchers are enabling the battery-free operation of
ultra-low-power wireless devices for everything from medical
implants to that black-box under the seat of new automobiles. If a
sensor is needed but it is inconvenient to supply power--from the
inside of a jet engine to the heart's aorta valve, for
example--energy harvesters are being designed to convert
environmental gradients into usable electrical power.
The latest batch of energy harvesters for vibrations use
piezoelectric actuators sized to match the energy required by the
application, from centimeter-sized fibers ruggedized to supply
milliwatts in harsh environments, all the way down to micron-sized
actuators fabricated using micro-electromechanical systems (MEMS) to
supply microwatts to wireless sensors...
Source: E.E.Times, by R. Colin Johnson.
Energy Harvesting Conference
which took place last month in San Jose,
CA, was the first industry conference to focus on energy harvesting,
the ability of a device to acquire and use energy from its
surrounding and to eke out power from its environment. Topics
included RF-power transmission and harvesting and storing
vibrational, thermal, and piezoelectric energy. Designers look to
energy harvesting to deliver a reliable source of power in extreme
conditions for as long as 20 years, a capability that seems beyond
the scope of small, price-competitive batteries."
Source: EDN Magazine.
Potential Wireless Power Health Issues
"Health issues arise as possible concerns about using RF-power
transmitters as sources of wireless power. Regan Zane, PhD, of the
University of Colorado -- Boulder presented a paper [at the 2007 Nano-Power
] , Efficient low-power RF energy harvesting
and power management,
which included a comparison of
radiation levels for common consumer appliances with the level of
radiation you'd see in an RF-power transmitter."
Source: EDN Magazine.
See the Blog for some health related commentary.
Low Energy/Chemically Assisted Nuclear Reactions
This site features a library
of papers on Low Energy Nuclear Reactions (LENR), which are
also known as Chemically Assisted Nuclear Reactions (CANR).
See also: IEEE Spectrum September 2004.
This technology is what is destined to replace
the older Radioisotope Heater Units (RHU), as long term,
low power, power sources.
"Cold Fusion" without the baggage.
Plastic Sheet Delivers Wireless Power
"Plastic sheet delivers wireless power" on Nature's news
feed. Japanese researchers have created a thin plastic sheet
capable of supplying up to 40 W of power to products on or near to
it. Sure, the products need to have a special receiving coil to
accept the power from the sheet, but it's still immensely clever.
"...As a demonstration of the product's safety, the paper shows
it powering an LED at the bottom of a bowl containing water and a
Source: Sensors Magazine.
Selecting the Right Battery System
- Selecting the Right Battery System for Cost-Sensitive
Portable Applications While Maintaining Excellent Quality."
Piezoelectric Ceramic Fibers
are now avaliable from Advanced Cerametrics Incorporated (ACI)
"ACI's composite materials generate ten times the amount of power
from waste mechanical energy as other flexible forms of piezo
materials. This functional amount of power can be used for self
powering electronic loads, damping vibrations or morphing
structures. Harvested mechanical energy (vibration, compression or
flexure) can all be tapped to deliver extreme life span power in
places previously impossible."
Energy Harvesting Modules
are now available from Advanced Linear Devices, Inc. (ALD)
"These Modules are designed for low power intermittent duty and long
storage time applications. Specific on-board functions include energy
capture and accumulation, energy storage, power conditioning and
energy management from various energy sources, such as solar cells,
PZT piezoelectric ceramic composite elements, inductive elements and
micro thermal-electric generators. EH300 Series Modules can easily
adapt to a variety and wide range of voltage and power inputs and
outputs. Energy can be collected from many types of secondary or
waste by-product environmental sources, such as thermal, mechanical,
chemical, solar, biological and human body sources."
Trawoeger: Pyramid Electric Generator
I'll admit this one might be a bit 'out there' but then people said
Airplanes could not fly after the Wright Brothers had already did
it. Looks simple enough to build one and try to see if it
works, and that is a mighty big 'if'.
Source: Rex Research.