Wireless Electricity In Bangkok

[The_Munchmaster]

Sounds like fantasy days are returning.

[baa99]

http://www.youtube.com/watch?v=PdrqdW4Miao

[Guest]

We have gone from morse code with wires, to radio and television, Landlines with wires to mobile phones using electromagnetic waves. Who would have thought that possible not so long ago. I know very little about this excuse my ignorance, but induction seems to work.

 

From what I see of the video posted on magnectic induction, it does seem possible to exchange power without wire from one point to another. Admittedly not very much power, but it's a start and if the idea exists and it has been proven to work in principle then maybe it's possible to do anything.

[radioman]

Currently its all about scaling. Getting a small amount of energy from one place to another is possible, heck I was doing this 35 years ago when a mate lived in the shadow of a large medium wave transmitter. There was enough energy on his property that with a decent wire antenna and a suitably robust detector we could charge a 1.5 volt cell. But a multi thousand dollar transmitter with a 150 foot transmitting antenna mast laid out on several acres of land is a rather inefficient battery charger, there are better ways.

 

In the electromagnetic field(sic) radiation follows an inverse square law characteristic so to maintain a given level of signal when the distance doubles requires 4 times as much power. Triple the distance and you need 9 times the power. to get more signal at a given distance requires similar increases.

 

Induction may be a frog of a different flavour, can't comment, but to do meaningful transmission of power using electromagnetic radiation would seem to be a wasted effort with our current understanding of physics and the materials available to make it work. Advances will likely come, possibly even so far as a practical capability to some extent but don't hold your breath. That journey from the wired telegraph to the mobile phone took over a hundred years.

[Guest]

Technogy is amazing a while ago in a shopping mall I once saw a demonstration of a small halogen cooking hob. On it was a pot of boiling water which they lifted off the surface. Then invited everyone to touch the surface which was immediately cold ! how does that work ?

[baa99]

That was an induction stove. The pan gets hot via induced currents but the stove top stays cool.

 

[radioman]

In a related but not exactly on topic vein a BBC television documentary series from a good few years back is worth watching. Connections presented by James Burke explores the way scientific developments are connected and how to reach one level of invention others must have come first. There are 3 series and I think the first is from the late 70's so quite old but well worth the download time.

 

http://en.wikipedia.org/wiki/Connections_%28TV_series%29

 

A torrent search should produce results.