Why can't we transmit electricity through air somehow the way we can transmit radio waves?

Answer 1

This was the dream of Nikola Tesla.
Nikola Tesla (Smiljan, near Gospic, Austrian Empire (now Croatia), July 10, 1856 – c. January 7, 1943 in New York) was a Serbian-American inventor, physicist, mechanical engineer and electrical engineer.

His nationality is disputed between Croatians and Serbs. Tesla himself said that he was equally proud of his Serbian heritage as of his Croatian homeland [1].

Tesla is recognized among the most accomplished scientists of the late 19th and early 20th centuries. His patents and theoretical work form the basis of modern alternating current electric power (AC) systems, including the polyphase power distribution systems and AC motor, with which he contributed to the Second Industrial Revolution.

In the United States, Tesla's fame rivaled that of any other inventor or scientist in history or in popular culture. After his demonstration of wireless communication in 1893 and after being the victor in the "War of Currents", he was widely respected as America's greatest electrical engineer. Much of his early work pioneered modern electrical engineering and many of his discoveries were of groundbreaking importance. Never putting a large focus on his finances, Tesla died impoverished and forgotten at the age of 86. In his later years, Tesla was regarded as a mad scientist and became noted for making bizarre claims about possible scientific developments

Wireless energy transfer, by definition, does not require a physical medium through which to flow. Anyone can demonstrate that energy can be transmitted without a direct physical connection by simply touching the ends of a wire, briefly, to the ends of a small battery. Hold the wire near a compass needle while you do this and you'll see the compass needle twitch. It takes energy to make something move, so you've transmitted energy wirelessly. The needle moves because the electric current which briefly flows through the wire generates a magnetic field which acts on the needle (see electromagnetic induction and magnetic field for more information).

Another, more dramatic demonstration of wireless energy uses a radio transmitter generating more than a few watts, such as an amateur radio transmitter. A Fluorescent lamp with no wires attached to it, held near the antenna, will glow when the transmitter is activated. Send "SOS" and the light blinks "SOS". The transmitted energy causes the gas inside the lamp to glow, like the northern lights.

Once the basic principle is established, then the problem is to concentrate the energy of the transmission so that most of it is received where it can be converted into useful power. Think of a flashlight that lets you focus the light beam or spread it out so that it's very wide. If you wanted to shine the flashlight on a solar cell, you'd want the flashlight's beam to be tightly focussed to reduce the amount of energy which does not fall on the receiver and is lost.

Early systems (such as Tesla proposed) were incapable of such "focusing" of transmitted energy, because the necessary antenna size is impractically large at low frequencies (see extremely low frequency radio waves). Without focusing, much of the energy would be lost to the atmosphere.

The advent of technology for much higher transmission frequencies (such as those used by microwave transmitters) created the possibility of "beaming" the energy through the use of directional antennas, such as the one invented by Hidetsugu Yagi. Lasers, which create a coherent and tightly "beamed" form of light energy, are even more appropriate.

In most cases the cost of such solutions is much higher than simply using copper wire. Wireless energy transfer, then, is most interesting for applications where the energy receiver can't be copper-tethered to the energy source — such as sending energy to an airplane or spacecraft, or another planet, or in the case of solar power satellites, from orbital satellites to a rectenna on Earth.

Answer 2

It is 100% possible to send power via Electromagnetic waves and it is being done, however it is more trouble than it is worth for consumer needs for several reasons. First of all, the frequency would need to be somewhere around 60-100 GHz. Secondly, the amount of power needed at the transmitter would be astronomical in order for the wave not to attenuate to zero after a few meters. Third, this amount of power would cause detrimental effects on the human body, should someone obstruct the beam. These, as I mentioned, are not feasable for household applications, but there are several applications being researched. The most interesting is the powering of zeppelins from the ground. In Japan there is an array of 50+ satellite dishes that beam 65 GHz power beams up to a zeppelin in the middle troposphere.

Answer 3

Transmission through the air is extremely inefficient since it is omni-directional. The key to electricity transmission is getting the power to where you want it with the minimum amount of loss. Wires are by far the best way to do that. If you did transmit power through the air, there is also the danger that someone will step in front of the beam.

Answer 4

Yes 1) Through a spark - very high p.d. ionises the air, as in lightning. 2) Via an electromagnetic radio wave. This produces a tiny current in the receiving antenna. 3) By electromagnetic induction, as in a transformer.

Answer 5

The transmission of electricity requires the flow of electrons while the transmission of radio waves requires the flow of photons. Although electrons and photons can both flow through air, the apparatus for transmission and strength of flow are very different. A bolt of lightning produces a violent flow of electrons and also a flow of photons detected on radio (and TV) as static. The static signal is of course much weaker (luckily for the radio!).

Answer 6

Electrical conductivity of a medium depends on the value of permitivity.
This is denoted by the Greek alphabet epsilon.

The value of permitivity of air is 8.554*10^ - 12 which is almost equal to zero.
So current cannot pass through air.

The permitivity of air can be changed by reducing pressure. Best example is the tubelight in which there is conduction of electricity through gases. The pressure in tubelight is nearer to vacuum.

Radio waves are electromagnetic in nature and they does not need any medium to travel. They can travel even through vacuum. They are transverse in nature and are independant of medium. They can pass through anything

Answer 7

first of all air is not very good medium to transmit electricity and next it can harm alot of sensitive people unlike radio waves

Answer 8

consider the case of ligtning it produces more power in an uncontrollable manner inorder to transmit E through air hi power in terms of Trillion KVA is needed

Answer 9

Yes we can but it is highly inefficient.

If you're dealing eith higher current and voltage, it is dangerous and impractical.

Answer 10

We can.Google it! ;)