Yes, that's the main issue with the harebrained scheme. How it's done now is that the AC mains are rectified and smoothed, and then that DC is switched on and off at a high frequency into the primary of a transformer.
That generates a well-contained magnetic field which builds up and collapses at the switching frequency, causing a voltage to be induced in the secondary winding of the transformer, which is then rectified, smoothed, and regulated as required for the device it's driving. The thing about the transformer is that the magnetic field is largely contained within the structure of the transformer and nearly all of the energy in the primary is transferred to the secondary, with the result being that a well-designed switching power supply can have an efficiency surpassing 80%, with some going over 90% The wireless scheme requires that a magnetic field be generated with a large loop of wire (the primary of the transformer) and that the secondary be part of the device being charged/operated, with the energy transfer occurring when the secondary is in the field created by the primary. The fly in the ointment is that there's no way to concentrate the energy in the field (as is done in the core of the transformer) and couple it efficiently through air to the secondary in the device being charged/powered. The result of that is that efficiency of the system would be _very_ low; I'd guess at 5% or less. Unfortunately, this little fact (which should be known to anyone with even a passing interest in power conversion) seems to been overlooked by the "researchers" trying to foist this huge boondoggle on the public. Even more disgraceful, in my opinion, is that this "primary" would be on 24/7, wasting a huge amount of power. On Mon, 14 Sep 2009 07:59:53 -0500, you wrote: >Yet another report on the coming of Wireless power: > >http://www.cnn.com/video/#/video/tech/2009/09/13/electricity.without.plugs.c >nn > >http://tinyurl.com/rbrpk9 > >While I love the idea primarily for its convenience I harbor the suspicion >that we are about to unleash the mother of all power vampires across the >national landscape during a critical time in our history when we are trying >to conserve energy. Or is that not the issue? > >Comments? > >Regards >Steven Vincent Johnson >www.OrionWorks.com >www.zazzle.com/orionworks
