2. CONTENTS
INTRODUCTION
HISTORY OF WIRELESS POWER
PRINCIPLE BEHIND WITRICITY
HOW WITRICITY TECHNOLOGY WORKS
FIRST MOVER AND INNOVATOR
MIT’S EXPERIMENT
WITRICITY - MAGNETIC INDUCTION
WITRICITY VS RADIATIVE POWER TRANSFER
FEATURES
APPLICATIONS
PROS & CONS
CONCLUSION
REFERENCES
3. INTRODUCTION
WITRICITY Wire less electricity
The technique of transmitting power without
using wires with an efficiency up to 95% with
non-radiative methods.
The Transmission of electrical energy from one
object to another without wires.
4. History of Wireless Power:
In 1899, Sir Nikola Tesla
Proposed a method of Wireless
Power Transmission. As it was a
Radiative mode, most of the
Power was wasted and has less
efficiency.
The efficient midrange
power transfer concept is
Witricity. In this model
source and load are in
Magnetic resonance so
there is no power loss.
5. PRINCIPLE BEHIND WITRICITY
It is based on the simple physics principle that “Energy can be
transferred wirelessly by utilizing magnetically coupled
resonance”.
Strong coupling between electromagnetic resonant objects
causes transferring of energy wirelessly between them.
6. Resonant coupling occurs when natural frequencies of two
objects are approximately same. It involves a pair of copper
coils for the energy transmission
7. How it would look and work in your office or bedroom
8. Nikola Tesla (1856 - 1943)
“Nikola Tesla, the eccentric - and unbelievably under-
rated - genius known as the ‘wild man of electronics’,
was without doubt one of the greatest minds in the
history of the human race.”
He investigated radio transmission
and reception and designed his own
transmitter
Used this same coupled-tuned-circuit
oscillator to implement his non-
radiative conduction-based wireless
energy transfer.
Later it was forwarded by MIT
SCIENTISTS
9. MIT’S EXPERIMENT
In 2006,5 members team of
researchers of MIT
experimentally demonstrated
transfer electricity with out
wires
They were able to lit a 60W
bulb ,from a source placed 7
feet away with absolutely no
physical contact between the
bulb and the power.
The team also demonstrated
how the magnetic near field
can transfer power though
10.
11. Many wireless information
broadcasting uses radiation of
radio frequency energy.
It is an inefficient means of power
transfer because the vast majority
of radiated power is wasted into
free space.
Witricity technology for power
transfer is non-radiative & relies
on near field magnetic coupling.
12. FEATURES
Highly Resonant Strong Coupling Provides High
Efficiency Over Distance.
Flexible geometry for being embedded.
Highly secure on exposure to Human.
Line of sight rule need not to be followed.
13. EFFICIENCY
The efficiency of such system depends upon :
Relative size of the power source and the capture device.
Distance between the devices.
As common building and furnishing materials are essentially
“transparent ”to magnetic fields they enable witricity
technology to efficiently transfer power through them.
The power not absorbed by the capture device comes back to
the power source and gets absorbed by it.
16. Pros Cons
•Significant decluttering of office •Need for standardization and
space. adaptation.
•No need for meter rooms and •Retrofitting old equipment or
electrical closets. purchasing new equipment
could become a very expensive
•Reduction of e-waste by endeavor.
eliminating the need for power
cords. •Possibility of “energy theft”. Wi
Fi, someone can be using your
•Need more light , no need for internet or your power.
electrician. Simply place the lamp
wherever needed.
17. ADVANTAGES
1. No need of line of sight in witricity power
transmission
2. Less costly - The components of transmitter and
receivers are cheaper. So this system is less costly.
DISADVANTAGES
1. Wireless power transmission can be possible only in
few meters.
2. Efficiency is only about 40%.
18. CONCLUSION
We can envisage a future in which the world of
wireless arrives with witricity.
Witricity corp. is working to make this future a
reality, developing wireless electricity
technology that will operate safely and
efficiently over long distances ranging from m
to km and will deliver power ranging from mW
to kW.
19. References
1. An article published in the Science Magazine as “Wireless Power Transfer via Strongly
Coupled Magnetic Resonances” by Andre kurs, Science 317, 83(2007); Dol:10.1126/
science.1143254.
2. H. Haus , “Waves and Fields in Optoelectronics”, Prentice hall Publishers, Englewood
3. http://electron9.phys.utk.edu/optics507/modules/m6/coupled_resonators.htm
4. “Efficient Non-Radiative Midrange Energy Transfer” by Aristeidies karalis, Marlin Soljacic's.
5. James O. McSpadden, “ Wireless Power Transmission Demonstration”, Texas A&M
University, June, 1997.
6. http://www.designnews.com/blog/I_Have_The_Power_/929MIT_Team_Invents_WiTricity_
Wireless_Energy_Transfer.php
7. http://news.bbc.co.uk/2/hi/technology/6129460.stm
