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Page 1: Wireless Power Transmission: Witricity -An Advanced … · such as mobile phones, mp3 ... and charging stations that clutter millions of ... for long distance power transmission using

International journal of recent advances in engineering & technology (IJRAET)

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ISSN (Online): 2347 - 2812, Volume-4, Issue -9, 2016

1

Wireless Power Transmission: Witricity -An Advanced Generation

1Anusha.B.K,

2PreranaKulkarni,

3Trupthi.G,

4Shwetha.D

1,2,3,4Department of EEE, East West Institution of Technology, Bengaluru 560091

Abstract- This paper describes an original idea to eradicate

the dangerous usage of electrical wires which involve lot of

confusion in particularly organizing them. We cannot

imagine the world pertaining to electricity. We can

conceive a future in which power transfer without electric

wires is practicable. We present the idea of transmission of

electricity without wires i.e., Witricity (wireless power

transmission). Power crisis is one of the huge problem of

the present century. We can’t even survive without

electricity. Just imagine our daily usage electronic devices

such as mobile phones, mp3 players, laptops, computers

and other portable electronic devices which are competent

of charging themselves without being plugged in for

charging. This paper consists of the techniques of power

transmission without using wires with an efficiency of

about 95% with non-radiation methods. This paper is

mainly based on:-

1) The popular technology called Tesla Theory

2) Solar power satellite (Microwave power transmission)

Index Terms-Microwave power transmission (MPT), solar

power satellite (SPS), Tesla theory and Wireless electricity.

I. INTRODUCTION

In our present electric power transmission and

distribution system half of the power is wasted. Most of

the electric power is being wasted during transmission

from generating station to the consumers. The ability to

communicate with people on the move has evolved

remarkably and wireless communication services have

been enthusiastically adopted by us throughout the

world. In this manner power distribution looks like

outdated with using big transmission lines and cables.

The present transmission and distribution scheme has

heavy losses and comparatively low efficiency. Hence it

is necessary for us to replace the present transmission

method with the efficient one. The demand for power is

increasing day by day, at the same manner power loss is

also increased. The utmost reason for loss of power is

the resistance of wires used for electrical grid

distribution system. This loss indicates that our system

of distribution of electricity is only 70-75% efficient.

According to the World Resources Institute (WRI) the

highest transmission and distribution losses in the world

is India's electricity grid. Hence it is very necessary for

us to have an alternate technology to transmit and

distribute the power.

II. TESLA THEORY

In this remarkable discovery of the "True Wireless" and

the principles upon which transmission and reception,

even in the present day systems, are based, Dr. Nikola

Tesla shows us that he is indeed the "Father of the

Wireless". The famous Wardenclyffe tower (Tesla

Tower) shown in fig.1was constructed and designed

mainly for wireless transmission of electricity rather

than telegraphy. In 1893, Tesla demonstrated the

illumination of vacuum bulbs without using wires for

transmission of power at the world Columbian

exposition in Chicago. This was the first broadcasting

system in the world. Tesla wanted to transmit electricity

from this tower to the whole globe without wires using

the Ionosphere.

Fig.1the 187-foot Wardenclyffe Tower (Tesla Tower) in

1903.

The most popular concept known is Tesla theory in

which it was firmly believed that Wardenclyffe shown

in fig.1would allow wireless transmission and reception

across large distance with negligible losses. He had also

made numerous experiments of high quality to give

validity to his assert of possibility of wireless

transmission of electricity. But this was an unfortunate

incidence that people of that century was not in a

position to recognize his magnificent work otherwise

today we may transmit electricity wirelessly and will

Page 2: Wireless Power Transmission: Witricity -An Advanced … · such as mobile phones, mp3 ... and charging stations that clutter millions of ... for long distance power transmission using

International journal of recent advances in engineering & technology (IJRAET)

_______________________________________________________________________________________________

_______________________________________________________________________________________________

ISSN (Online): 2347 - 2812, Volume-4, Issue -9, 2016

2

convert our mother earth a wonderful adobe full of

electricity. This was the first step towards a practical

wireless system. Tesla realized that electrical energy

from one source can be sent externally into space and

that can be detected by a receiving instrument in the

surrounding area of the source without the need of any

interconnecting wires. His views and his experimental

work are showing a path to the development for the

world. Fig.2 below is the Tesla's apparatus for

transmission of electricity.

Fig 2. System of transmission of electrical energy

III. MICROWAVE POWER

TRANSMISSION

The most extended documented area of research is being

done with the aim of putting solar power generating

satellites into space and transmitting power to earth

stations. This was first introduced in1968 and all of the

experiments thus far have only been carried out in

terrestrial laboratories.

Fig.3 solar power satellite

William C. Brown, the chief delegated power on

wireless power transmission technology, has loaned this

demonstration unit to the Texas space grant consortium

to show how power can be transferred through free

space by microwaves. A block diagram for this is as

shown in fig.4.

Fig.4 Block diagram of solar power satellite

Space-based solar power has three main components-

1. Microwave source

2. A transmitting antenna

3. Receiving rectanna

The microwave source consists of a microwave oven

magnetron and high power handling capacity. The

output microwave power ranges from 50W to 2.45 GHz.

A co axial cable connects the output of the microwave

source to a coax-to-wave guide adapter. The microwave

source is protected from reflected power by adapter

which is connected to a tuner and bidirectional coupler

to match the waveguide impedance to the antenna input

impedance. The slotted waveguide antenna contains 8

waveguide sections with 8 slots on each section. These

64 slots radiate the power uniformly through free space

to the rectanna. A rectifying antenna called a rectanna

receives the transmitted power and converts the

microwave power to direct current (DC) power. This

rectanna has a 25% collection and conversion efficiency,

but retinas have been tested with greater than 90%

efficiency at 2.45 GHz.

The transfer of power without wires is now possible and

can be rapidly applied with the design and construction

of my "high-potential magnifying transmitter". There

were three important theories regarding this-

1. Transmission through or along the earth

2. Propagation as a result of terrestrial resonances

3. Coupling to the ionosphere using propagation

Page 3: Wireless Power Transmission: Witricity -An Advanced … · such as mobile phones, mp3 ... and charging stations that clutter millions of ... for long distance power transmission using

International journal of recent advances in engineering & technology (IJRAET)

_______________________________________________________________________________________________

_______________________________________________________________________________________________

ISSN (Online): 2347 - 2812, Volume-4, Issue -9, 2016

3

It has been experimented that electrical energy can be

propagated around the world between the surface of the

earth and the ionosphere at extreme low frequencies,

what is known as the Schumann cavity. We know that

resonant cavity can be excited and power can be sent to

that cavity similar to the techniques applied in

microwave ovens for home use, it should be possible to

resonate and deliver power via the Schumann cavity to

any point on earth. Tesla experimented many techniques

to prove wireless power transmission is possible.

Even though he was not able to apply this system in a

market, latest scientific theory and mathematical

calculations support his invention that the transmission

of power without wires is now possible and a practicable

alternative to the comprehensive and costly grid of

electrical transmission lines used today for electrical

power distribution.

Another possibility is to use highly efficient fiber lasers

for wireless power transmission where the possibilities

are similar to microwaves concept but lasers emit energy

at frequencies much higher than microwaves. For

several years NASA, ENTECH and UAH have been

working on various aspects of collection of the laser

radiation.

IV. MERITS, DEMERITS AND ECONOMIC

IMAPCT OF WIRELESS ELECTRICITY

4.1 MERITS

Wireless technology is efficient and easy. The cost of

electricity used is reduced by the system. Need for grid

is eliminated. Maintenance cost is low. More effective

when the transmitting and receiving points are along a

line of sight. This system can reach the places which are

remote. This technology reduces the need of power

cables. Wastage of power is minimized. Reduction of e-

waste by eliminating the need for power cords, does not

interfere with radio waves & negative health

implications. Transfer efficiency in this technology will

be more compared to copper coil. This technology

creates shock free environment, avoid of any chances of

power thefts. Provides solution to the ever increasing

demand for power.

4.2 DEMERITS

This technology is radioactive. When lasers are used

conversion is inefficient and absorption loss is high.

When microwaves are used interference may arise.

Operating frequency can be decreased within a specific

range. If not, it will affect the power transfer efficiency.

Frequency below 1 MHz preferably 200 KHz is

applicable for power transfer in the present system.

4.3 ECONOMIC IMPACT

Wireless electricity is expected to have its biggest

impact in the mobile electronic device and electric car

markets in which three-fourths of power is wasted in

idle mode. You cannot feel the oscillating magnetic field

wireless electricity used to transfer the power. Wireless

electricity can eliminate the complicacy of power cables

and charging stations that clutter millions of offices and

home entertainment rooms. Wireless electricity has

many environmental benefits. Companies make about 40

billion disposable batteries each year and wireless

electricity could do away with that.

V. CONCLUSION

The wireless energy system uses common materials,

such as copper wire and capacitors that cause no danger

to humans. The efficiency of the medium used also

matters a lot, since radio waves have proven to be much

more directional than microwaves, which covers a much

larger distance. So radio waves can be used for wireless

power transmission in the future and research in the

same has proven 95% conservation rate of energy,

which proves that it is a really efficient means of

transfer. The requirement of a wireless mode of transfer

of electricity is necessary because this is nonhazardous,

efficient and safe to all problems faced by us. The

efficiency is restrained to increase since there is no issue

of power loss over wires and coils instead of being lost

in the process of transfer. With the development of

efficiency of the transfer mediums, now we can choose

for long distance power transmission using the power of

wireless modes.

REFERENCES

[1] Nikola Tesla," The Transmission of Electrical

Energy Without Wires as a Means for Furthering

Peace," Electrical World and Engineer. jan.7,p.

21,1905.

[2] Nikola Tesla, My inventions, Ben Johnson, Ed.,

Austin, Hart Brothers, p.91, 1982

[3] Thomas F. Valona, "Tesla's Wireless energy...

For the 21st century!!! One step beyond direct

TV!!!" Extra Ordinary Technology, 1, no.4, oct/

nov/dec 2003.

[4] Thomas Benson, "Wireless transmission of

power now possible", News Letter, pp1118-9,

March, 1920.

[5] Nikola Tesla," The true wireless”, Electrical

Experiments, May, 1919.

[6] James O. McSpadden, "Wireless Power

Transmission Demonstration”, Texas A&M

University, June, 1997.

[7] “Goodbye wires..." MIT News

[8] Nikola Tesla's Wireless Systems.