Wireless power transmisssion means transmission of electrical power from one place to another place ie. from a electrical source to a load where we need a continous energy supply but its impossible or not convenient with wires/gridThe size of the components is dictated by:

1)distance from transmitter to receiver

2)the wavelength of the radiation

3)the laws of physics,

specifically the Rayleigh Criterion or Diffraction limit, used in standard RF (Radio Frequency) antenna design, which also applies to lasers. These laws dictate that any beam will spread (microwave or laser) and become weaker and diffuse over distance. The larger the transmitter antenna or laser aperture, the tighter the beam and the less it will spread as a function of distance (and vice versa). Smaller antennas also suffer from excessive losses due to side lobes.

Then the power levels are calculated by combining the above parameters together, and adding in the gains and losses due to the antenna characteristics and the transparency of the medium through which the radiation passes. That process is known as calculating a Link Budget.

The efficiency of an energy transferring system is the percentage of energy sent which reaches the destination. Sending energy through wires is often more efficient because wires represent a low loss way to confine and guide the energy to where it is needed. Still, generally, wireless energy transfer works very well at short range; and efficient long-distance transfer is possible if the transmitters and receivers are physically large, or if the energy can be formed into a tight beam, such as with lasers or large microwave dishes. Ultimately, beamwidth is physically determined by diffraction due to the dish size in relation to the wavelength of the electromagnetic radiation used to make the beam.

Microwave power beaming can be more efficient than lasers, and is less prone to atmospheric attenuation caused by dust or water vapor. However, microwaves have much longer wavelengths than visible light, and require proportionately larger transmitters and receivers to deal with diffraction over long distances.

The most efficient laser power beaming system today has photovoltaic panels optimized to the wavelength of the laser. Losses due to atmospheric spreading can be reduced by the use of adaptive optics, and losses due to absorption can be reduced by a properly chosen laser wavelength. Laser power beaming does not work well through clouds.

Although laser and photovoltaic technologies have been rapidly advancing, it is unknown what transmission efficiency improvement is possible. The most efficient lasers are laser diode arrays, which can surpass 50% efficiency, but such lasers do not have mutual coherence. Other options include standard chemical lasers with efficiencies of a few percent or less. The development of high-coherence diode laser arrays would allow for notably improved power usage efficiency, as laser inefficiency comprises most of the energy loss.

applications

* The electric toothbrush battery charger * The induction cooker stovetop

It can be argued the cookware part of an induction cooker is not a secondary in the strictest sense of the term. It is more accurately described as the non-laminated core of an alternating-current electromagnet, in which eddy currents are induced resulting in the heating effect.

* The electromagnetic card reader The act of swiping the card induces eddy currents in the reader which are measured. * Transcutaneous energy transfer (TET) systems in artificial hearts and other surgically implanted devices. * Devices using induction to charge portable consumer electronics such as cell phones.

ELECTRICAL CONDUCTION

Electrical energy can also be transmitted by means of electrical currents made to flow through naturally existing conductors, specifically the earth, lakes and oceans, and through the atmosphere - a natural medium that can be made conducting if the breakdown voltage is exceeded and the gas becomes ionized. For example, when a high voltage is applied across a neon tube the gas becomes ionized and a current passes between the two internal electrodes. In a practical wireless energy transmission system using this principle, a high-power ultraviolet beam might be used to form a vertical ionized channel in the air directly above the transmitter-receiver stations. The same concept is used in virtual lightning rods, the electrolaser electroshock weapon and has been proposed for disabling vehicles. The Tesla effect. The Tesla effect.

A "world system" for "the transmission of electrical energy without wires" that depends upon the electrical conductivity was proposed by Nikola Tesla as late as 1904. The Tesla effect is the application of a type of electrical conduction (that is, the movement of energy through space and matter; not just the production of voltage across a conductor). Tesla stated,

Instead of depending on induction at a distance to light the tube .. ideal way of lighting a hall or room would be to produce such a condition in it that an illuminating device could be moved and put anywhere, and that it is lighted, no matter where it is put and without being electrically connected to anything. I have been able to produce such a condition by creating in the room a powerful, rapidly alternating electrostatic field. For this purpose I suspend a sheet of metal a distance from the ceiling on insulating cords and connect it to one terminal of the induction coil, the other terminal being preferably connected to the ground. Or else I suspend two sheets as .. each sheet being connected with one of the terminals of the coil, and their size being carefully determined. An exhausted tube may then be carried in the hand anywhere between the sheets or placed anywhere, even a certain distance beyond them; it remains always luminous.

Through longitudinal waves, an operator uses the Tesla effect in the wireless transfer of energy to a receiving device. The Tesla effect is a type of high field gradient between electrode plates for wireless energy transfer. Wireless transmission of power and energy demonstration during his high frequency and potential lecture of 1891. Wireless transmission of power and energy demonstration during his high frequency and potential lecture of 1891.

The Tesla effect uses high frequency alternating current potential differences transmitted between two plates or nodes. The electrostatic forces through natural media across a conductor situated in the changing magnetic flux can transfer power to the conducting receiving device (such as Tesla's wireless bulbs).

Currently, the effect has been appropriated by some in the fringe scientific community as an effect which purportedly causes man-made earthquakes from electromagnetic standing waves, related to Tesla's telegeodynamics mechanical earth-resonance concepts.[33][34] A number of modern writers have "reinterpreted" and expanded upon Tesla's original writings. In the process, they have sometimes invoked behavior and phenomena that are inconsistent with experimental observation. On the other hand, a number of researchers have experimented with Tesla's basic wireless energy transmission system design and made physical observations that are inconsistent with some basic tenets of mainstream science.

The Tesla wireless system would combine electrical power transmission along with broadcasting and wireless telecommunications, allowing for the elimination of many existing high-tension power transmission lines and facilitate the interconnection of electrical generation plants on a global scale.