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Didn't Tesla at one point envision giant coils that would basically give you "wireless electricity" through the use of changing magnetic fields? This is cool b

by jtchang 14y ago

Didn't Tesla at one point envision giant coils that would basically give you "wireless electricity" through the use of changing magnetic fields? This is cool but I'd be worried if it caught on in any sort of scale.

yareally 14y ago
Yes. http://en.wikipedia.org/wiki/Wardenclyffe_Tower http://en.wikipedia.org/wiki/Wardenclyffe_Tower I think the resulting resistivity and wasted electricity would make it unfeasible for mass usage over distances even if it had been funded to completion. I wish portable device OEMs would adopt inductive charging more though. No worrying about cables or broken ports.
- csense 14y ago
  If you lost a $5 cable or broke your $1 charging port, the OEM is economically motivated to get you to shell out a three-digit figure for a new phone. Given this simple and obvious observation, the fact that phone manufacturers have mostly dropped proprietary charging interfaces in favor of USB seems like a minor miracle.
  - yareally 14y ago
    Yeah, very true. It's actually pretty easy to replace USB ports on many mobile devices. I read about users doing it all the time on Android forums and rather cheaply. Mostly depends on how easy the device is to open up and repair though.
tiziano88 14y ago
The main problems with having a huge EM field to power the entire planet (or even just a city) are that: - every piece of conductor of the right length is basically an antenna for the frequency at which the EM field resonates, therefore will generate a voltage across its extremities that can generate wild sparks and cause electric shocks; - an EM field (and pretty much any other field) in the space is proportional to the inverse of the square of the distance from the source, which makes it for a pretty inefficient way of transmitting energy at long distances. The field could be not isotropic, for instance by "focusing" it in one direction, but that defeats the purpose of accessing the energy from everywhere.

by jtchang 14y ago

yareally 14y ago

Yes. http://en.wikipedia.org/wiki/Wardenclyffe_Tower http://en.wikipedia.org/wiki/Wardenclyffe_Tower I think the resulting resistivity and wasted electricity would make it unfeasible for mass usage over distances even if it had been funded to completion. I wish portable device OEMs would adopt inductive charging more though. No worrying about cables or broken ports.

csense 14y ago
If you lost a $5 cable or broke your $1 charging port, the OEM is economically motivated to get you to shell out a three-digit figure for a new phone. Given this simple and obvious observation, the fact that phone manufacturers have mostly dropped proprietary charging interfaces in favor of USB seems like a minor miracle.
- yareally 14y ago
  Yeah, very true. It's actually pretty easy to replace USB ports on many mobile devices. I read about users doing it all the time on Android forums and rather cheaply. Mostly depends on how easy the device is to open up and repair though.

tiziano88 14y ago

The main problems with having a huge EM field to power the entire planet (or even just a city) are that: - every piece of conductor of the right length is basically an antenna for the frequency at which the EM field resonates, therefore will generate a voltage across its extremities that can generate wild sparks and cause electric shocks; - an EM field (and pretty much any other field) in the space is proportional to the inverse of the square of the distance from the source, which makes it for a pretty inefficient way of transmitting energy at long distances. The field could be not isotropic, for instance by "focusing" it in one direction, but that defeats the purpose of accessing the energy from everywhere.