What is wireless electricity??
As the name suggests, wireless electricity refers to the transfer of electric energy from a power source to the desired equipment which acts as the sink and collects the energy without the use of messy wires. Using this technology one may charge his laptop or mobile without having to plug it into the wall.
Who began it??
Work on producing wireless electricity was started by Nikola Tesla in 19th century. His principle of producing wireless electricity went like this…If a single one-megaton nuclear warhead were exploded 300 miles over the center of the country, a high-voltage electromagnetic pulse would in theory disrupt communication and electrical systems. Gamma rays emitted by such an explosion would instantly strip away the electrons from air molecules in the upper atmosphere in roughly a circular, pancake-shaped zone. The free electrons would then accelerate radially with the earth's magnetic field, separating from the heavier, positively charged ions and creating a downward directed high-voltage electromagnetic pulse. This in turn results in electrical surges in all exposed conductors on the ground. He got a major break through when in 1899 he transmitted 100 million volts of high frequency power wirelessly over a distance of 26 miles and lit 200 light bulbs and ran an electric motor and only about 5 % of the energy was lost in transmission. When Tesla was determining the resonant frequencies of the earth to potentially transmit unlimited electric power, he also recognized frequencies that acted as a damping field to nullify electric power.
How can it be done for household purposes??
Today's wireless transfer of energy, such as the transfer of light energy from the sun for solar power or the transfer of microwaves from transmitters for communication, involves relatively low levels of energy. But recharging devices like laptops requires a much higher level of energy. And if this was routinely zapped through the air it could 'fry' any living organisms that get in the way. But Prof Soljacic of MIT says he has found a way of transmitting energy so that only the devices that it is recharging will pick it up, so it will not affect humans. Instead of using traditional radiation, the non-radiative part of electromagnetic field can be used. Devices can be tuned to the frequency of this field and thus act as a sink for all the energy the transmitter gives out. Prof Soljacic says this would prevent energy radiating out to areas it does not need to go to, providing an efficient and safe method of wireless energy transfer. An object of the size of a laptop could be recharged within a few meters of the power source. Placing one source in each room could provide coverage throughout out home. Prof Soljacic also thinks the technology could be used to power freely roaming robots in a factory.
Hurdles in the path...
Some physicists say that the challenge is finding a 'magic' frequency that does not also affect living organisms and thus pose possible health risks. “You would be reintroducing all the problems that we went through with mobile phones," says Dr Geoff Anstis of the University of Technology, Sydney. “And it wouldn't be until a couple of decades that you may be happy that there isn't a significant problem. “His colleague Professor Geoff Smith agrees and says there are also technical challenges in keeping the devices tuned with the transmitters, thus preventing the general release of stray energy. “I think this is nice physics but there's a way to go before it would be possible," says Prof Smith. He says any changes in the surrounding environment could "de-tune" the system and stop the safe and efficient transfer of power. Electrical engineer Dr Trevor Bird of CSIRO's ICT Centre says attempts so far to develop wireless power transfer have not been very successful. He agrees that safety and technical barriers to wireless power systems are huge. Dr Bird also says that, depending on the frequency of the field, the antenna on the device being recharged may have to be very large.
Achievements so far...
With the advent of the wireless and Tesla's unique investigations into broadcasting electricity, a dozen or more inventors thereafter announced their own means for transmitting electrical energy without wires. One British inventor, H. Grindell-Matthews, actually demonstrated his "mystery ray" apparatus in 1924. When his beam was directed toward the magneto system of a gasoline engine, it stopped the system. Afterwards, it ignited gun powder, lit an electric lamp bulb from a distance and killed a mouse in seconds! Grindell-Matthews said the secret was involved with the "carrier beam" he used to conduct a high-voltage, low-frequency electrical current. During 1936, Guglielmo Marconi experimented with extremely low frequency (ELF) waves and displayed their exceptional ability to penetrate metallic shielding. These waves could affect electrical devices, overload circuits and cause machines like generators, electric motors and automobiles to stall. Diesel engines, which do not rely on electrical ignition, were not affected.
Industrial steps taken so far…
Mobilewise has taken the initiative of providing a safe, wire-free electric power technology and its products finally deliver the freedom to be fully mobile!!
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