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Energous Says Its Truly Wireless Charging Technology Will Ship Later This Year — In Next iPhone?
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Exactly -- I wasn't the one who brought the sun comparison up, only showing that it isn't really comparable.
In any case, it isn't necessarily the frequency that is harmful but the total amount of energy being emitted. There are limits to the maximum permissible level, and it would appear that this company's solution (which is not new or revolutionary) would exceed those limits if it were to work at all.
I feel like this would've been done a while ago if it could have been done. What cutting-edge technology is there here?
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I don't know if wireless charging would emit dangerous levels of RF, but seriously, you guys can't pretend to know either.
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RF is known to be dangerous at high levels, not because of cancer risk but for other reasons like tissue heating. You certainly should not stand in the way of, say, a TV signal transmitter. https://en.wikipedia.org/wiki/Microwave_burn
I don't know if wireless charging would emit dangerous levels of RF, but seriously, you guys can't pretend to know either.
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I read all the info on Energous`web-page and it seems that the solution is designed to distribute the power to authorised units when they actually need it. It includes prioritisation as well. On the other hand it is basically an unshielded microwave oven that is supposed to be capable of sending its beams to designated directions. So, it may be safe, may be not. The safer it will remain, the slower it will be. So - if you'll need to jump into your office for e/g half an hour and have <20% left, then just don't expect miracles... I don't think to be able to get completely rid of cables yet. Having all "small" devices powered by it, however, especially if they are low-power stuff (headphones, sensors, mice, keyboards (coupled with small solar panels), etc...), is tempting as it means that all devices that never actually leave the charging area may be usable for years without service... provided that chargers (transmitters) will not suck your pockets dry at start.
The question is only to what degree.
I'm skeptical they'll be able to charge a device at a reasonable rate or distance while below the emission limits.
It better be long distance, because other wise the induction charging is just another "port", such as the apple watch. If you have to physically touch the "wireless" charger to the device, it is not wireless in my opinion. I want to be able to hide a power transmitter under my bed or desk, and have everything no matter where it is charging. I don't care if the range is only like 1m thats still amazing.
ARGUMENT 1) "Muh Cancer"
Microwaves have a wavelengths of ~10^-2 m (.000124 eV) Radio are even longer. Ionising radiation is any photon that has >124 nm wavlength (10 eV). Thats five orders of magnitude in energy difference, there is NO WAY a microwave (or a radio wave for that matter) is knocking off an electron or damaging your DNA. Its like throwing an orange at a tank and expecting it topple over. Visible light is "more" of a cancer risk than your phone (Not to be confused with natural light that contains photons >10eV).
ARGUMENT 2) "Muh brain cooking"
The power in a kitchen microwave is 1000 watts. Even then after 3 minutes the centre of your lunch is still cold! A mobile phone is 0.2 watts. Thats another 4 orders of magnitude in power difference. Even then it falls off following the inverse square law, meaning after its gone through your thick(er) skull it would be even less than that. The heat that it generates is so small, you go through orders of magnitude larger temperature swing during the day. Does it worry you, that in the morning it was 16 deg C and now its 22 deg C? No, didnt think so.
Now, use your phone, and stop paying attention to pseudoscience!
Microwaves have a wavelengths of ~10^-2 m (.000124 eV) Radio are even longer. Ionising radiation is any photon that has >124 nm wavlength (10 eV). Thats five orders of magnitude in energy difference, there is NO WAY a microwave (or a radio wave for that matter) is knocking off an electron or damaging your DNA. Its like throwing an orange at a tank and expecting it topple over. Visible light is "more" of a cancer risk than your phone (Not to be confused with natural light that contains photons >10eV).
ARGUMENT 2) "Muh brain cooking"
The power in a kitchen microwave is 1000 watts. Even then after 3 minutes the centre of your lunch is still cold! A mobile phone is 0.2 watts. Thats another 4 orders of magnitude in power difference. Even then it falls off following the inverse square law, meaning after its gone through your thick(er) skull it would be even less than that. The heat that it generates is so small, you go through orders of magnitude larger temperature swing during the day. Does it worry you, that in the morning it was 16 deg C and now its 22 deg C? No, didnt think so.
Now, use your phone, and stop paying attention to pseudoscience!
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Even if this works well, and poses no health risk, it will be a highly inefficient (i.e. energy-wasting) solution.
Poor example, as sunlight causes skin cancer!
Poor example, as sunlight causes skin cancer!
The technology is based on the transmitter's ability to precisely locate the receiving chip (such as in our phone). The transmitter then uses an antenna array with a great many antennae to focus its transmitted energy very specifically towards the receiver chip. (or to each of them if there are more than one).
While it's true that it will be slower charging than wire, that doesn't matter if it can keep the phone fully charged while using it when we're at home, at the office, in the car, or anywhere else with such wireless transmitters.
If this works as advertised it would be beautiful. That IS a big if.
At least it's a high fraction
Even standard Qi chargers are about 85% efficient. Finer tuned chargers with higher wattages can get into the high 90s.
Yep, unless something gets in the way. Like a person or even their hand. That blockage forces the transmitter to try reflecting off walls or ceiling to reach a target device. (I suspect the device constantly reports back the amount it is receiving, as guidance for the antenna directivity.) The extra distance involved really dissipates the power of course.
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Needing hundreds of watts of power assumes that there is only 1 receiver chip in the device. A single chip can have multiple antennae (each able to gather few milliwatts) and the chips are so small that there will be multiple chips located strategically on the phone MB. The technology is valid, it is just a matter of applying it in a new device design. As far as transmitters needed, your PC monitor or laptop could (will) have them too. How far away from your PC do you work? Just sayin', don't poo-poo the idea, much brainier guys than you and I are behind this technology.
Experts are doubtful. Plus the way the company is run smells like a scam, or at least an idea that's a long way from reality. The CEO gets a ridiculous $2 million a year from their limited funding. And they refuse to say how much power it will require.
Speaking of which, their prospectus specially warns that they require far more antenna power (third parties calculate hundreds of Watts) than what the FCC normally allows (max 1 Watt) from such a device, and that anyone who licenses their tech is on their own trying to get around that.
Here's some interesting views:
https://seekingalpha.com/instablog/...search/4952551-energous-corporation-watt-game
https://seekingalpha.com/article/3811296-energous-buy-companys-story-stock
http://spectrum.ieee.org/energywise...n-energous-deliver-on-wireless-power-promises
But if they can pull off their promises, more power to them! (no pun intended)
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