witricity full report

[seminar class]

Presented by:
Shilpa gupta

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WITRICITY “The power without wires”
What is wpt?
Conventional energy transfer is done by using wires
The transmission of energy from one place to another without using wires.
Wireless power transfer is made possible by using various techniques
Why not wires?
Electrical energy transfer is through wires.
Most of energy loss is during transmission.
On an average, more than 30%.
In India it exceeds 40%.
Insulator cost is very high in wired transmission.
System becomes highly complex
Problem of power theft.
Why wpt?
Reliable
Efficient
Low maintenance cost
Fast
Can be used for short-range or long-range
TYPES AND TECHNOLOGIES OF W.P.T.
Microwave power transfer
Transfers high power from one place to another. Two places being in line of sight usually
Steps
Electrical energy to microwave energy
Capturing microwaves using rectenna
Microwave energy to electrical energy
5,000 MW Receiving Station (Rectenna), Snohomish, Washington. This station is about a mile and a half long
LASER transmission
LASER is highly directional, coherent
Not dispersed for very long
But, gets attenuated when it propagates through atmosphere
Simple receiver
Photovoltaic cell
Cost-efficient
Advantages of far- field energy transfer
Efficient
Easy
Need for grid, substations etc are reduced
Low maintenance
More effective when transmitting and receiving points are along a line of sight
Can reach the places which are remote
Disadvantages of far–field energy transfer
Radiative
Needs line of sight
Initial cost is high
When LASERs are used,
Conversion is inefficient
Absorption loss is high
When MICROWAVES are used,
Interference may arise
Fried bird effect
How safe is wpt?
Human beings or other objects placed between the transmitter and receiver do not hinder the power transmission
Magnetic fields tend to interact very weakly with the biological tissues of body, and so are not prone to cause any damage to any living beings