This document discusses piezoelectric transducers and nanogenerators. It describes how piezoelectric transducers can convert mechanical energy into electrical energy using zinc oxide nanowires. A nanogenerator contains an integrated circuit with nanowires that generate charge when bent by an applied force. Nanogenerators can harness energy from small vibrations in various applications like mobile phones, gyms, footwear, and more. While pollution-free and requiring low maintenance, they have limitations such as being prone to cracking and potential interference from stray voltages.
2. Contents
⢠Introduction
⢠Piezo electric transducer(nanogenerator)
⢠Inside a nanogenerator
⢠Working principle
⢠Sources which nanogenerator can exploit
⢠Applications
⢠Limitations
4. Developers of Nanogenerators
Dr. Zhong Lin (Z.L.) Wang and his colleagues at Georgia Institute of Technology,
Georgia State, USA have made significant leaps in developing nanogenerators
over the last decade.
5. ⢠Piezoelectric Transducer- When an external
force is applied on to a quartz crystal, there will be a
change in the voltage generated across the surface.
This change is measured by its corresponding value
of sound or vibration.
6. Piezoelectric Transducer
⢠Ability to create electrical potential when compressed,
expanded or changed in shape (Mechanical energy to
Electrical energy).
⢠Made up of Zinc Oxide wires called Nanowires.
⢠Produces 45mv whenever the zinc wire is pulled back and
forth.
⢠Wires have
diameter of : 100-300 nm
Length of : 10-100 micron
7. Inside A Nanogenerator
⢠Consists of an integrated
circuit.
⢠Nanowire bends and generates
an electrical charge.
⢠Several electrodes capture
power from millions of
nanowires.
8. How it works?
⢠Working principle of
Nanogenerator where
an individual nanowire
is subjected to the force
exerted perpendicular
to the growing direction
of nanowire.
9. Sources which Nanogenerators can exploit
⢠For Large scale applications (from wherever periodic
kinetic energy exists) :
1. Wind,
2. Ocean Waves.
⢠Small scale applications :
1. Tiny physical motion,
2. Inhalation of lung,
3. Heartbeat,
4. Muscle movement,
i.e. Any kind of movement!!
10. MOBILE KEYPADS & KEYBOARDS
ď Crystals laid down under keys of
mobile unit and keyboard.
ď For every key pressed vibrations
are created.
ď These vibrations can be used for
charging purposes.
11.
12. GYMS AND WORKPLACES
ď Vibrations caused from
machines in the gym.
ď At workplaces,
piezoelectric crystal are
laid in the chairs for
storing energy.
ď Utilizing the vibrations in
the vehicle like clutches,
gears etc.
13. POWER GENERATING BOOTS OR SHOES
ď Idea was researched in US.
ď To power the battlefield equipment
by generators embedded in soldier
boots.
ď Idea was abandoned due to the
discomfort.
14. ADVANTAGES DISADVANTAGES
Unaffected by external
electromagnetic fields.
They cannot be used for truly
static measurements
Pollution Free
Can pick up stray voltages in
connecting wires.
Low Maintenance Crystal is prone to crack if
overstressed.
Easy replacement of
equipment.
May get affected by long use
at high temperatures.
15. CONCLUSION
ď Piezoelectricity is a revolutionary source for âGREEN ENERGYâ.
ď Flexible piezoelectric materials are attractive for power harvesting
applications because of their ability to withstand large amounts of strain.
ď Convert the ambient vibration energy surrounding them into electrical energy.