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Wireless Power Over Distance: Just a Parlor Trick?
Lucas123 writes "Companies like U.S.-based WiTricity and China-based 3DVOX Technology claim patents and products to wirelessly powering anything from many feet away — from smart phones and televisions to electric cars by using charging pads embedded in concrete. But more than one industry standards group promoting magnetic induction and short-distance resonance wireless charging say such technology is useless; Charging anything at distances greater than the diameter of a magnetic coil is an inefficient use of power. For example, Menno Treffers, chairman of the Wireless Power Consortium, says you can broadcast wireless power over six feet, but the charge received will be less than 10% of the source. WiTricity and 3DVOX, however, are fighting those claims with demonstrations showing their products are capable of resonating the majority of source power."
The problem is inefficiency. Power drops with the square of distance. That means you need a bigass transmission source to get a small amount of power any distance away, hence why things like FM stations have 5 digit wattage transmitters.
Yes we have been able to transmit power wirelessly for a long time, no it is NOT practical or efficient. If you are enthralled with Tesla, spend some time reading some actual books on him, not just the silly piece by the Oatmeal. He was a fascinating man and worth your time to learn about, but you need to learn about him if you want to go spouting off.
He didn't invent some magic transmission technology we can't replicate, he invented an inefficient transmission technology that we can replicate, but don't, because he was not able to solve the efficiency problems (and it may not be physically possible to).
If anyone went through with this kind of thing they SHOULD be charged by the power sent. It is, after all, taking that much power to charge your device. The wastage is your problem for being too lazy to plug in your phone.