News RCA announces WiFi-sucking battery

http://www.bit-tech.net/news/bits/2010/04/05/rca-announces-wifi-sucking-battery/1

 

Six hours in a strong signal? I'll stick to using a plug and cable thanks.

 

But you have to sleep at some point.

 

True, but there's no mention off efficiencies here.
Which uses more power? Using a cable for (say) an hour during the day, or leaving you're wifi on all night? I usually turn it off if I don't need it as my main PC uses a wired network.
I guess if you have wifi at work then someone else would be paying for it.

 

Cool, but its just an extension of a Tesla coil.
I would certainly prefer this than a charging mat or USB, it means you can just leave your phone around the house and it gets charged.
But yes it will terribly inefficient, but phones use no power anyway so the cost would be nothing per year.

 

If wifi can charge a battery set up like this - how much radiation is wifi pumping into our bodies?

 

Lots. ^_^

I wonder if regular radio-waves can't be used.

 

Won't this just mean you piss of the neighbours/family by reducing the strength of any wi-fi signals about >_<

 

@confusis
Here's something that might make you reach for your tinfoil hat: wifi uses a frequency extremely close (within about 50Hz) to the magnetron in a microwave. Actually, you probably don't want that hat as we all know what happens when you put tinfoil in a microwave

 

Humbug! The FCC regulations prevent WiFi routers from exceeding 1 Watt of power. A normal laptop battery has a capacity of around 50 Watt-Hours which means that in a perfect world where the device captures 100% of all the energy and sends it to the battery, it will take 2 days of charging to reach a 100% charge that might last you 6 hours at best.

Now, we do not live in a perfect world. Your router is almost certainly not high powered operating at 1 Watt, and this devices ability to charge your battery is also not even close to 100%, and the device is not capturing your entire WiFi signal.

Assuming that the receiver has a surface area of 400cm^2 (10cm by 40cm).
And you place your laptop a meter away from the router.
And you have a high powered 1 watt router.
And we live in a perfect world where everything has perfect efficiency and the receiver's normal is directly pointing at your router providing maximum surface area.

Only about 1/314th the energy from the router will get to the laptop. This is a little over 3mW. It would take about 20,000 hours to charge a 60WH battery. Enjoy using your laptop for 2 hours every year.

 

Double post

 

This is precisely what I was thinking. And it can't be argued that it could charge a mobile phone, either: phones use more than 3mW while sitting idle, so you wouldn't even be able to keep an idle phone from discharging with this tech.

 

I'm going to go a step farther and question the integrity of RCA all together. Every house has a 40W light bulb, incandescents are about 10% efficient so they are radiating 4 times as much energy in the visible spectrum as the most powerful routers and we already have devices to capture this energy called solar panels. Now, if you tried plunging in a small solar panel on the back of your laptop and said it would power it, most people would find that absurd. But when you are using invisible radiation from routers, people have absolutely no idea how little power it is.

 

Wasn't this announced ages ago, with a demo of them charging a Blackberry from it? and people worked out then that it couldn't even provide the standby power required by a phone.

I can see this potentially being useful in one of those backup batteries, you can just leave it in your bag and it keeps itself topped up. No more than that at this stage, and not for a primary charging mechanism for a long time/if ever.

 

I'd say april fool, since it's so clearly nonfeasible, but that'd be four days too late.

 

third paragraph

"draws power from thin air in the forum (should this be form) of surrounding WiFi signals"

 

There's about 15 trillion trillion neutrinos going through your body every second. But like wifi signals, are completely harmless. Brainiac did a nice experiment to prove this - they got 100 mobile phones around an egg, and got each one sending/recieving microwave radiation. Did it cook the egg? No. Such low power.

Scaremongering comes from those who just do not understand and think scientists are all evil and live in volcanos *cough*Daily Mail*cough*

 

The idea behind this device is if you work in the city or such - you're around wifi signals all the time. Or take where I live in small block of flats in Oxford: 24 families in close proximity, all with wifi enabled homes. Having a device like this to charge my NDS, or mobile, or camera, would be an interesting concept to put into practice.

However, I'd prefer this tech in the equipment itself, and charging mats to put the device onto, as previously suggested.

 

Uh, 100 phones times 2W = 200W which isn't enough to cook an egg, but it would certainly have heated the egg up.

 

Radiant energy decreases at a rate of distance squared. You could have 24 routers 5 meters from your laptop and they still wouldn't provide the power of the 1 router a meter away that would take 3 years to fully charge a laptop battery.