Wireless Electricity And The Pandora2

[mali]

That would be a problem, until Craig makes them white

But the solar cells aren't white and 30%/70% still stands
/smartass

 

[Butterman]

If we dispense with magical thinking for a minute and think about these wireless power technologies rationally, they become undesirable very quickly. It is impossible to transmit power omnidirectionally and efficiently (unless your receiver is a Dyson sphere). It is also impossible to transmit energy efficiently over any substantial distance using magnetic fields. Whatever the scam artists at Witricity tell you, their product either works at a tiny fraction of the efficiency claimed, or doesn't work at all.

You're missing the point, it's not about transmitting energy over distance, it's about eliminating cables. We did some similar tests in a lab on campus last year after I came across a paper from these guys and over the distance of about a half meter we were getting 40% to 50% efficiency. Considering our gear was made with duct tape and various bits of spliced wire, we were very suprised. I'll see if I can find any of the pictures.

 

[renwils]

Does anyone know if this stuff can interfere with sensitive audio equipment? Any time someone's cellphone rings I get a ton of interference in one of my guitar amplifiers.

 

[Butterman]

Does anyone know if this stuff can interfere with sensitive audio equipment? Any time someone's cellphone rings I get a ton of interference in one of my guitar amplifiers.

The system SHOULD only interfere with other devices resonating at a certain frequency.

http://en.wikipedia.org/wiki/Resonance

 

[Wheels]

You're missing the point, it's not about transmitting energy over distance, it's about eliminating cables. We did some similar tests in a lab on campus last year after I came across a paper from these guys and over the distance of about a half meter we were getting 40% to 50% efficiency. Considering our gear was made with duct tape and various bits of spliced wire, we were very suprised. I'll see if I can find any of the pictures.

That's horrible. I'd rather have wires running around on the floor than spend twice as much in energy costs just to power a few gadgets from nearby transmitters. Also, as Chip said, power drops off rapidly with distance (I think a point-source follows the inverse-square law?), so you would have to place all your devices very close to the transmitter for it to work at all. I'm also concerned about the field inducing currents where you may not want them, namely in any coil inside the device that isn't supposed to be a power supply.

RCA's "demo" looks like smoke and mirrors to me. Their charger has an internal battery, which is probably what recharged the phone. Their wireless inductor would be practically useless except perhaps to a) stave off self-discharge in the unit's battery, B) maybe charge the battery after a few days of being left right by a wifi router. I would rather just plug something into a wall wart for an hour or two. Remember that 802.11 transmitters are generally capped at 1W EIRP, and they radiate their signals outward as a rounded sphere-like volume rather than a tight, directional beam. This works fine for normal use because your receiver only has to be able to pick up a tiny amount of current as a signal to interpret, much lower than you could use to charge a modern, power-hungry portable gadget.

 

[Butterman]

Yes, it follows the inverse square law. Yes, it's horrible, like I said, our equpiment is hacked together, we did the tests over the course of a week.

This isn't about distance. Imagine they supplied PC PSUs with this technology, the PSU is typically within a meter of every other component, (mouse/keyboard/monitor/amp). So, if this technology was combined with wireless devices, that giant horrible mess of cables that lives behind every computer would be gone.

I hate my spaghetti of cables. I've tried expensive cable systems, but then every time I go to a LAN I have to spend at least an hour carefully taking everything apart.

 

[j6cubic]

RCA's "demo" looks like smoke and mirrors to me. Their charger has an internal battery, which is probably what recharged the phone.

They admitted as much. The Airnergy's battery was pre-charged.

Their wireless inductor would be practically useless except perhaps to a) stave off self-discharge in the unit's battery, B) maybe charge the battery after a few days of being left right by a wifi router. I would rather just plug something into a wall wart for an hour or two. Remember that 802.11 transmitters are generally capped at 1W EIRP, and they radiate their signals outward as a rounded sphere-like volume rather than a tight, directional beam. This works fine for normal use because your receiver only has to be able to pick up a tiny amount of current as a signal to interpret, much lower than you could use to charge a modern, power-hungry portable gadget.

As someone pointed out on /., charging something from an 802.11 transmitter does take a bit. Granted, the calculations in that post assume a distance of 10 meters but you can't guarantee you'll be closer to a hotspot much of the time and everywhere you can guarantee being closer you'll most likely have easy access to a power outlet.

Wireless power transmission has some useful applications. The Airnergy is not one of them.

 

[kattle87]

wireless, wireless, wireless...
This is just stupid in my really honest opinion... What we really need is "single cable fits all", as was already pointed out in the thread.
Then, you pick up one hub, with 6 slots, you can plug whatever you want. You are done, and no other cables are needed (maybe 1 plug for your PC PSU and 1 for the TV, but I'm not sure about the latter). There was some speaking about Light Peak... Well, I think that that's the way to go. End Of Line! 100 GB are enough for everything, including plugging in your brain to the matrix, probably.

 

[WizardStan]

They already have one single cable. The end looks like this in the US, and this in the UK

 

[Pleng]

And what is the single connector at the OTHER end of the cable...?

 

[WizardStan]

And what is the single connector at the OTHER end of the cable...?

The other end of the cable is the device itself.

 

[elwing]

They already have one single cable. The end looks like this in the US, and this in the UK

lol, not a single powercable, I meant a single cable for the device featuring power, USB + video out or something like that it would be even better if i could use the same cable for a different device

 

[borgqueenx]

Just use a laserbeam
http://en.m.wikipedia.org/wiki/Wireless_energy_transfer?wasRedirected=true

 

[Jourdy288]

That strikes me as in interesting idea... @BorgqueenX:
Did you visit that page on your iPhone?!
*GASP*

 

[borgqueenx]

That strikes me as in interesting idea... @borgqueenx:
Did you visit that page on your iPhone?!
*GASP*

Yes. Just seen it was a mobile page
wikipedia in app store said "this item is not available anymore" so...

My notebook is on repairs for about one and a half week.

 

[bzar]

They already have one single cable. The end looks like this in the US, and this in the UK

lol, not a single powercable, I meant a single cable for the device featuring power, USB + video out or something like that it would be even better if i could use the same cable for a different device

Slashdot just yesterday reported on displayport 1.2 which could do just that and more.

EDIT: No, I failed. I didn't read "power" there