Witricity is the wireless transmission of electrical energy without wires. It works through magnetic resonance between coupled magnetic resonators, transferring energy through near-field magnetic induction. The technology was pioneered by researchers at MIT who wirelessly powered a 60W light bulb from over 2 meters away in 2007. Witricity could enable applications like wirelessly charging consumer electronics, powering industrial robots and sensors, and automatically charging electric vehicles. It provides benefits over traditional induction and radiation-based wireless power by transferring energy efficiently over distance while avoiding health risks. However, more research is still needed to increase efficiency and transmission range before witricity sees widespread commercial use.

1. WITRICITY
Presented by
OGUNBODE AMOS OLUSOJI
AAA061668
Electronic and Communication Physics
Department of Pure and Applied Physics
Ladoke Akintola University of Technology, Ogbomoso,
Oyo State.

2. What is witricity?
Witricity is nothing but wireless
electricity.
Transmission of electrical energy from one
object to another without the use of wires
is called as Witricity.
Because of Witricity some of the devices
won't require batteries to operate.

3. WIreless electricity
Story behind WITRICITY
The story started late one night a few
years ago. It was probably the sixth time
that month that MIT Professor Marin
Soljacic was awakened by his mobile
phone beeping battery low. At that time
it occurred to him that there is
electricity wired all through his house,
office-everywhere. He think about- how
it is possible to use electricity without
using wires…
Coupled Resonators

4. Basics of WITRICITY
Energy
coupling
Electricity
Magnetism
Electromagn
etism
Magnetic
Induction
Energy/Pow
er Coupling
Resonance
Resonant
Magnetic
Coupling

5. BASICS
Electricity is the flow of
electrons(current) through a
conductor (like a wire), or
charges through the
atmosphere(like lightning). A
convenient way for energy to
get from one place to another.
Magnetism is a force that acts
at a distance due to a
magnetic field. This field is
caused by moving electrically
charged particles or is
inherent in magnetic objects
such as magnet.

6.  Electromagnetic induction is
the production of voltage across a
conductor moving through a
magnetic field.
 Electromagnetism is one of the
four fundamental interactions of
nature, along with strong
interaction, weak interaction and
gravitation. It is the force that
causes the interaction between
electrically charged particles; the
areas in which this happens are
called electromagnetic fields
 Energy/Power Coupling:
Energy coupling occurs when
an energy source has a means of
transferring energy to another
object

7.  Resonance :is the tendency of a
system to oscillate with larger
amplitude at some frequencies
than at others. These are known
as the system's resonant
frequencies (or resonance
frequencies). At these
frequencies, even small periodic
driving forces can produce large
amplitude oscillations
 Resonant Magnetic Coupling:
Magnetic coupling occurs when
two objects exchange energy
through their varying or
oscillating magnetic fields.
Resonant coupling occurs when
the natural frequencies of the
two objects are approximately
the same.

8. WITRICITy technology
The Transfer of Electricity from one place to another without
wires is known as “Witricity”.
There is witricity power sources(transmitter) and capture
devices(receiver).
Power source provides power to the devices where as capture
device captured it to work.
Power source and capture devices are specially designed
magnetic resonators.
Magnetic resonators efficiently transfer power over large
distance via the magnetic near-field

9. Near field
• Near field is a wireless transmission
technique over distances comparable
to or a few times the diameter of
devices.
• Near field is usually magnetic.
• Near field energy is non radiative .but
some radiative and resistive losses will
occur.

10. Coupled resonators
Two resonant objects of the same
resonant frequency tend to exchange
energy.
It exchange energy strongly ,while
interacting weakly with living beings
and other environmental objects.
Coupled resonators are said to be
operate in strongly coupled regime to
avoid material absorption and radiative
loss.

11. Strong coupling
 Strength of interaction is very high.
 Coupling constant ‘g’>=1
 Energy transfer is very efficient.
 The rate of energy transfer is substantially
higher than rate of energy lose.

12. MIT teams behind witricity technology
The first experiment of witricity, the concept of
wireless electricity, was conducted in the year 2006, by
researchers from Massachusetts Institute of
Technology. The Assistant Professor of this team of
researchers was Marin Soljacic.
2007: A physics research
group, led by Prof. Marin
Soljacic,at MIT, wirelessly
power a 60W light bulb
with 40% efficiency at a
2 meters (6.6 ft) distance
using two 60 cm-diameter
coils

13. Diagram of power source and capture
device oPower source is connected to ac
power.
oBulb is connected to capture device.
oBlue lines represent the magnetic
near field induced by the power
source.
oYellow lines represent the flow of
energy from the source to the capture
coil.
oThis powers light bulb.
oThe magnetic field can wrap around
the obstacle between power source
and capture coil.

18. Witricity technology is more than…
 Traditional magnetic induction.
Radiative power transfer.
Tesla’s vision of a wireless
world.

19. Traditional magnetic
induction
Used in power transformers.
 conductive coils transmit power to each
other wirelessly, over very short distance.
An electric tooth
brush uses
traditional magnetic
induction to
recharge its
batteries

20. Radiative power transfer
Radio frequency energy is used for
wireless power transfer.
Radiated power is wasted into free space
Need line of sight.
Harmful.
Microwave oven utilizes
radiation to cook foods

21. Microwave oven utilizes
radiation to cook foods
Microwave oven utilizes
radiation to cook foods
Tesla’s vision of a
wireless world
Nikola Tesla the most well
known scientist had a vision
of wireless world.
In which wireless electric
power and communication
would reach around the
world, delivering information
and power.

22. Features and benefits
Witricity’s Technology Technology Benefit
Highly strong coupling High efficiency over
distance
Energy transfer via
magnetic near field
Can penetrate and wrap
around obstacles
Non radiative energy
transfer
Safer for living beings and
other environmental
objects
Scalable design From Mw to Kw
Flexible geometry Device that can fit into
OEM (original equipment
manufactures) products

23. Applications
Consumer electronics
Industrial
Transportation…

24. WITRICITY APPLICATIONS
CONSUMER ELECTRONICS
 Automatic wireless
charging of mobile
electronics in home, car,
office,...while devices are in
use and mobile.
 Direct wireless powering of
stationary
devices…eliminating
expensive custom wiring,
unsightly cables and “wall-
wart” power supplies.

25. INDUSTRIAL
 Robots, package
machinery, assembly
machinery, machine
tools.
 Direct wireless power
and communication
interconnections at
points of use in harsh
environments.
 Direct wireless power
for wireless sensors
and actuators,
eliminating the need
for expensive power
wiring or battery
replacement and
disposal.

26. TRANSPORTATION
 Automatic wireless
charging for existing
electric vehicle classes:
golf carts, industrial
vehicles.
 Automatic wireless
charging for future
hybrid and all-electric
passenger and
commercial vehicles, at
home, in parking
garages, at fleet depots,
and at remote kiosks.

27.  Direct wireless power
interconnections and
automatic wireless
charging for implantable
medical devices .
 Automatic wireless
charging and for high
tech military systems.
 Direct wireless powering
and automatic wireless
charging of smartcards.
 Direct wireless powering
and automatic wireless
charging of consumer
Appliance, mobile robots,
etc.

28. ADVANTAGES
No need of line of sight.
No need of power
cables and batteries.
Does not interfere with
radio waves. Wastage of power is
small .
Negative health
implications.
Highly efficient than
electromagnetic
induction
Less costly.

29. Disadvantages
Wireless power transmission can be
possible only in few meters.
Efficiency is only about 40%.

30. FUTURE OF WITRICITY
aim is to get a robotic vacuum or a
laptop working, charging devices
placed any where in the room and even
robots on factory floors.
In another 3 to 5 years time. they will
come up with a witricity for commercial
use.

31. Witricity if successful will definitely change the way we live.
Imagine cellphones, Laptops, digital cameras getting self
charged!Engineers have got job on hand to reseacrh and
commercialise the technology. Till then it is a wait in
acticipation.

34. A Life with wireless electricity is beautiful and comfortable.

35. THANK YOU