04-10-2010, 09:42 AM
ABSTRACT
Don't you hate it when you forget to put your mobile phone on charge? Well, take heart - a new technology called WiTricity could mean never having to plug it in again. Welcome to the world of WiTricity. WiTricity, a portmanteau for wireless electricity, is a term which describes wireless energy transfer, the ability to provide electrical energy to remote objects without wires. The term was coined initially in 2005 by Dave Gerding and later used for the project of a MIT research team led by Prof. Marin Solijaci.
The wireless electricity works on the principle of using coupled resonant objects for the transfer of electricity to objects without the use of any wires. This concept of witricity was made possible using resonance where an object vibrates with the application of a certain frequency of energy. The MIT researchers have been able to power a 60 watt light bulb from a power source that is located about seven feet away. This was made possible using two copper coils that were twenty inches in diameter which were designed so that they resonated together in the MHz range. One of these coils were connected to a power source while the other, to a bulb. With this witricity setup, the bulb got powered even when the coils were not in sight.
The main advantages of witricity are that it is omni directional; the mess of wires can also be avoided .Thus enabling us in easy recharging of our electronic gadgets likes mobiles and laptops. Also, interactions of the environmental objects with the magnetic fields are suppressed since there is no tendency of interaction with the common materials. Its discovery is different from all previous effort because it uses “magnetically coupled resonance", which means it will not only be safe but it will be fairly efficient.
This technology is a big impediment to development in the retail sector right now. The wireless transfer of electricity has been a sci-fi dream up to this point, and truly, if electricity could simply be in the air, in the same way radio waves and wi-fi signals are, it would change the world.
INTRODUCTION
WiTricity, a portmanteau for wireless electricity, is a term which describes wireless energy transfer, the ability to provide electrical energy to remote objects without wires. The term was coined initially in 2005 by Dave Gerding and later used for the project of a MIT research team led by Prof. Marin Soljačić in 2007
Wireless power transmission is not a new idea, but to do so in an efficient way typically requires a directed beam like a laser or microwave. William C. Brown demonstrated in 1964 on the CBS Walter Cronkite news a microwave-powered model helicopter that received all the power needed for flight from a microwave beam (which requires the beam to be aimed at the aircraft as it flies). Between 1969 and 1975 Bill Brown was technical director of a JPL Raytheon program that beamed 30 kW over a distance of 1 mile between stationary points at 84% efficiency. Methods that don't require directed beams are typically very inefficient, as the energy is radiated in all directions (like a radio antenna) and only a small amount reaches the desired destination.
