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Author Topic: The uBeam FAQ  (Read 224571 times)

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Offline georgesmith

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Re: The uBeam FAQ
« Reply #75 on: November 10, 2015, 04:16:21 PM »
Winning a book on most detail ever published - what are you trying to do, land a job with them.  No, you are disputing them so not the case.  Are you with a competitor and merely want to take them out or whats the agenda here?

I think point #13 sums up OP's reasons quite well.

Your agenda, however, I'm not so sure of as you are a brand new user on this forum who just happened to choose this thread to make a first post. Are you a supporter and merely want to overlook OP's valid points by questioning his motives?

There is no agenda; merely doing research on the topic and was surprised at the number of detailed analyses by one individual. It made me wonder if they were working for a competitor, or maybe even used to work for ubeam. I was referred to this site by a fellow researcher.  One has to assume that the fellow putting so much effort into the analysis is wanting to compete, join, or debunk the company?

The recent LABJ article  might do that for him if the goal is debunking since the CEO is now being compared to Theranos who'd technology was also kept secret too long for critics.  But the details of the specs that ubeam released do offer some indications that there are a lot of huge risks ahead if ubeam ever hopes to bring a product to consumers at a reasonable price point.  The comparative data for Energous also makes one question their validity of claims, and yet they don't get the amount of blog criticisms. 
Aren't they, and for that matter, all new wireless power transmission endeavors including witriity destined to fail in the minds of those who aren't in the deep day to day engineering that each of the companies is chasing?  It is a new technology and has to overcome challenges or it wouldn't be worth inventing.  Conceding though that the challenges are fairly dominating in the timeframe they claim to be launching.

FWIW, I don't work for uBeam, and I also don't work for any uBeam competitor. I've never worked for uBeam, and I've never worked for a uBeam competitor. I'm not being compensated in any way. I have no financial interest at all here, and never have.
 

Offline LabSpokane

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Re: The uBeam FAQ
« Reply #76 on: November 10, 2015, 04:17:11 PM »
uBeam is "not in the market"??!!  Are they kidding?  They're marketing this perfumed bilge water in hopes of spinning it in an IPO.
 

Offline georgesmith

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Re: The uBeam FAQ
« Reply #77 on: November 10, 2015, 05:03:16 PM »
uBeam have given Techcrunch (whose owner runs CrunchFund, investors in uBeam) some new information:

http://techcrunch.com/2015/11/07/wireless-power-charger/

  • uBeam has developed a high-powered air-coupled ultrasonic transducer to transmit and receive sound waves at a single frequency within the range of 45kHz to 75kHz with an output of 145dB to 155dB (or 316 W/m2 – 3kW/m2)
  • uBeam can charge multiple devices simultaneously within a range of up to a 4 meter radius from a single transmitter
  • uBeam is designed to deliver a minimum of 1.5 watts of electricity to smartphones, or enough to keep a phone from losing battery life even when being heavily used. Depending on the number of devices being charged simultaneously by a single transmitter, and depending on the distance of those devices to the transmitter, uBeam could charge devices at comparable rates to a wire, or faster.
  • uBeam has 30-plus filed patents and 6 issued ones. At the core of its technology is the transducer the company invented, which it believes can deliver more power at the right frequency than any other.
  • The patents also cover technologies including its ultrasonic phased array transmitter that includes thousands of individually addressable and controllable elements, its beamforming algorithms that can shape and steer multiple beams to multiple moving devices, and the receiver that can harvest acoustic power from these beams coming in from multiple angles.
  • At launch, uBeam plans to both sell its transmitters and work with partners to install them in public places like restaurants, hotels, or cafes. It will also both sell the receiver phone cases and work with partners to loan them out to patrons of places with transmitters installed.

They claim "The information here about focused beams, frequency, and decibel level dispels many of the rumors about uBeam being too inefficient or unsafe. " with a link to this page behind 'rumors'.

They speak to Matthew O'Donnell: http://depts.washington.edu/bioe/portfolio-items/odonnell/
and Babur Hadimioglu https://www.linkedin.com/pub/babur-hadimioglu/8/799/b53

Would be fascinated to see a response from George Smith

(ps yes this is my first post, long-time lurker & youtube video watcher, first time poster)

Hey tombola. That article by Constine was both funny and a little depressing. A few weeks ago, Meredith Perry tweeted:

"Going dark until product launch. I'll tweet about other things, but uBeam's back in the vault. No press. Heads down & focused until launch."

I admired her for making the right decision: cutting down the PR hype. But one week later, she did an on-camera interview with the BBC, including a tour of the uBeam offices:

Could we soon charge our phones through the air?

And then two weeks later, that TechCrunch piece came out.  :palm:

The funny thing is that TechCrunch/Constine act like they're debunking skeptics, and then go on to confirm almost everything the skeptics said. Extremely high intensities: confirmed. (In fact, uBeam now claims to have the most powerful in-air transducers ever built.) Limited to line-of-sight: confirmed. Short ranges: confirmed.

The only thing different is the frequency. I assumed 100 kHz in my calculations, while TechCrunch quotes a range of 45 to 75 kHz. A lower frequency does give uBeam a somewhat longer range. But those frequencies are well within cat hearing range (cats top out at ~80 kHz), and the longer range also means stray noise travels farther. Going back to uBeam's website, it's interesting how they brush that under the rug:

"As for animals, only bats, cats, whales, and a few other animals could possibly detect the ultrasound that uBeam creates. We love aquatic animals but it is unlikely that uBeam would be used in the water! As for bats, these animals would hear uBeam only if it were used outside. Because uBeam uses "locked on" directional focused beams, only animals that carried a uBeam receiver would be able to "hear" the uBeam. uBeam's system will not affect pets or animals." (emphasis added)

They explain why bats and whales (mostly) aren't a problem, but appear to forget about cats. There are ~160 million cats in the US, so that's a significant oversight. It's a focused system, yes, but if it transmits 155 dB, and the goal is to keep noise leaks below "very loud" (~85 dB), the beam has to keep losses, reflections, dispersion, etc. under 0.00001%. That's just not practical.
 

Offline georgesmith

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Re: The uBeam FAQ
« Reply #78 on: November 10, 2015, 05:10:42 PM »
George Smith, you really need to question Energous' claims.

Quote
Energous is a publicly traded company (stock symbol WATT). Their website describes a charging technology called WattUp, which transmits power via radio waves[51]. Energous's website says that each WattUp transmitter can reach a range of 15 feet, and charge 12 devices at once[51]. Energous has signed a partnership agreement with a "tier one consumer electronics company"[52], likely Apple or Samsung[53], to include its technology in cellphones. uBeam's website claims that "RF [radio] and microwaves also both require impractically large transmitters and receivers to send power over distances greater than a meter"[1], but this appears to have been proven false by Energous's CES demonstration[8].

Here is the only article raising questions.
http://seekingalpha.com/article/3024956-energous-more-reasons-to-be-dubious

Energous claims 16W at 5 feet using 5.7 GHz.
http://www.tomshardware.com/news/energous-wattup-wireless-charging-haier,27944.html

Even assuming 100% efficiency and zero inverse square loss, the FCC transmit max is 1 watt and we all know EIRP doesn't actually mean more energy. If Energous did focus the energy, they'd have to drop 1 dB transmit power for every 3 dBi antenna gain. Either way they're likely going to face more than 99.99% beam spread loss.

Energous seems to be pulling the same stunt as RCA.


I haven't done in-depth investigation of Energous, so I can't speak to whether they exceed safety limits in that part of the radio spectrum. However, their device was recently tested by UL (link), and the results showed 4-5 watts at 5 feet, not 16 watts. Energous's stated design goal was 4 W at 5 feet, 2 W at 10 feet and 1 W at 15 feet.
 

Online coppice

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Re: The uBeam FAQ
« Reply #79 on: November 10, 2015, 05:22:42 PM »
I think this was brought up much earlier, but in a phased array type system, isn't there going to be substantial noise and harmonics in the negative space? Kind of how a fourier approximation can't quite perfectly make a step function, it has fuzzy noise at the corners.
Phased arrays won't necessarily give a lot of noise and harmonics. That's mostly an issue of the quality of the circuitry and transducers. However, practical arrays do give a lot of sidelobes, and the main lobe is not the kind of hard edged thing some of the descriptions of phased arrays seem to paint a picture of. To get the peak of the energy impinging on a small target across the room still leaves considerable energy going to all the wrong places.

I find it interesting that they keep emphasising how safe ultrasonic energy is, but also keep emphasising how safety concious the system is in cutting off power the moment something obstructs the beam. Seems like the are oscillating between two messages.  ;)
 

Offline georgesmith

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Re: The uBeam FAQ
« Reply #80 on: November 10, 2015, 05:52:52 PM »
The recent IEEE Spectrum article stated:

"With the exception of Perry, none of the engineers listed on uBeam’s patents are still at the company, according to their LinkedIn profiles."

IIRC, someone on Twitter replied (sadly can't find the source) that the engineers in question were contractors, not employees, and so were never expected to be at uBeam long-term. I looked up their LinkedIn profiles, and that seems to be accurate. In fact, uBeam looks like it had no full-time employees at all (other than Perry) before raising $10 million in October 2014. Article from Dec. 2014:

"Well, back in 2012, we had raised a bunch of money, I had this whole plan planned out, but it was extremely difficult because I was working with only contractors. Up until a few months ago, even. Until we raised our Series A [funding round, totaling $10 million and led by Upfront Ventures] we didn’t have any full-time employees except me."

There's nothing wrong with that, per se. It's good to hire slowly in the early stages of a startup. But back in 2012, a Pando article said:

"The company was created by Perry, a recent University of Pennsylvania grad and student ambassador at NASA. The idea? Enabling gadgets to recharge wirelessly via ultrasound transmitters. Perry plans to move her operation from New York to California. uBeam plans to launch a functional product by next year." (emphasis added)

Now that's just weird. Did Perry, uBeam's investors, and/or the media expect her to design, build, test, manufacture, and distribute a complex hardware product all by herself, with no other full-time employees? It just sounds strange.
 

Offline eneuro

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Re: The uBeam FAQ
« Reply #81 on: November 10, 2015, 05:55:22 PM »
http://spectrum.ieee.org/tech-talk/consumer-electronics/portable-devices/can-ubeams-throughtheair-phone-charging-system-live-up-to-the-hype
Thoroughly professional, researched, and pulls no punches. Exactly what you'd expect from the IEEE.

Now, we know why it looks like she doesn't know what she is talking about  :-DD
"In a TED speech from 2012, Perry seems to brag that she knew nearly nothing of physics before starting the company—not even how a TV remote control worked."

Today, with decent amount of money invested someone can  scam internet with nothing and maybe even make living on this for short time, but without any knowledge in the field, she will be only pink girl.
It is nice when someone comes from scientific research he made with someone else, and starts company, while he knows ehether it may work or not and push things in correct direction, but Mrs Perry after three years when started to learn something about ultrasound at least will undertand she was wrong.
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Online coppice

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Re: The uBeam FAQ
« Reply #82 on: November 10, 2015, 06:00:28 PM »
I haven't done in-depth investigation of Energous, so I can't speak to whether they exceed safety limits in that part of the radio spectrum. However, their device was recently tested by UL (link), and the results showed 4-5 watts at 5 feet, not 16 watts. Energous's stated design goal was 4 W at 5 feet, 2 W at 10 feet and 1 W at 15 feet.

I'm not saying it's is impossible to receive 4 watts at 5 feet, but your 5.7 GHz transmitters would have to be sending enormous amounts of energy, at least an order of magnitude greater than the energy received.  Since when does the FCC allow you to transmit 40+ watts on unlicensed 5.7 GHz?  The FCC max is 1W and you're only allowed to use 6 dBi gain when transmitting at max 1W.  You may use 30 dBi gain, but you must reduce transmit power by 8 dBm to use such a high gain antenna.
The FCC maximum applies to a single transmitter. They don't prevent you using numerous transmitters. Any large office is doing so, with multiple 802.11 APs in the 5GHz band. Energous seem to be using arrays to achieve their goals.
 

Online coppice

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Re: The uBeam FAQ
« Reply #83 on: November 10, 2015, 06:39:01 PM »
I haven't done in-depth investigation of Energous, so I can't speak to whether they exceed safety limits in that part of the radio spectrum. However, their device was recently tested by UL (link), and the results showed 4-5 watts at 5 feet, not 16 watts. Energous's stated design goal was 4 W at 5 feet, 2 W at 10 feet and 1 W at 15 feet.

I'm not saying it's is impossible to receive 4 watts at 5 feet, but your 5.7 GHz transmitters would have to be sending enormous amounts of energy, at least an order of magnitude greater than the energy received.  Since when does the FCC allow you to transmit 40+ watts on unlicensed 5.7 GHz?  The FCC max is 1W and you're only allowed to use 6 dBi gain when transmitting at max 1W.  You may use 30 dBi gain, but you must reduce transmit power by 8 dBm to use such a high gain antenna.
The FCC maximum applies to a single transmitter. They don't prevent you using numerous transmitters. Any large office is doing so, with multiple 802.11 APs in the 5GHz band. Energous seem to be using arrays to achieve their goals.

I did consider this, but now we're talking about using 40 transmitter+antenna pairs just to charge one phone!  And that's if you can actually deliver 0.1 watts with a single transmitter+antenna which is highly doubtful.  Dave Jones' video shows how absurd the whole idea is.
There is a video of one 5GHz power transfer demo (I think its Witricity) where the transmitter is hidden behind a curtain. However, at one point the curtain is moved, and you can see a huge array of PCBs making up the transmitter. These types of thing may be economically unrealistic for anything but specialist applications, but why let practically spoil the fun.  :)
 

Offline Delta

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Re: The uBeam FAQ
« Reply #84 on: November 10, 2015, 07:21:35 PM »
Are any regulatory bodies really going to allow 155dB of sound (at any frequency) in public places?  Surely not?
 

Online coppice

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Re: The uBeam FAQ
« Reply #85 on: November 10, 2015, 07:42:02 PM »
Are any regulatory bodies really going to allow 155dB of sound (at any frequency) in public places?  Surely not?
Is there anything to stop that right now, or would fresh regulation be required? The health and safety legislation in most places only seems to specify maximum sound intensities for frequencies up to 6kHz or 8kHz. This seems weird, as a machine putting out 155dB at 10kHz is definitely a problem.
 

Offline LabSpokane

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Re: The uBeam FAQ
« Reply #86 on: November 10, 2015, 09:35:07 PM »
Are any regulatory bodies really going to allow 155dB of sound (at any frequency) in public places?  Surely not?
Is there anything to stop that right now, or would fresh regulation be required? The health and safety legislation in most places only seems to specify maximum sound intensities for frequencies up to 6kHz or 8kHz. This seems weird, as a machine putting out 155dB at 10kHz is definitely a problem.

Ultrasonics are regulated in the US primarily due to the sub harmonics issue:

https://www.osha.gov/dts/osta/otm/noise/health_effects/ultrasonics.html

155 dB is totally out of the question. That is not a permissible exposure level at any frequency being discussed.
« Last Edit: November 10, 2015, 10:03:00 PM by LabSpokane »
 

Offline eneuro

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Re: The uBeam FAQ
« Reply #87 on: November 10, 2015, 11:26:07 PM »
Ultrasonics are regulated in the US primarily due to the sub harmonics issue:

https://www.osha.gov/dts/osta/otm/noise/health_effects/ultrasonics.html

155 dB is totally out of the question. That is not a permissible exposure level at any frequency being discussed.

Isn't this the first thing someone wanting to bring something "fantastic" to the market should check?  :palm:

Nice, I do want check how ultrasound is regulated in Euroean Union countries, to ensure this bloody u  :bullshit: Beam will never ever will be available there ;)

It must be regulated somehow, while giant wind turbine farms can make ultrasound too,  while its wing end passes the air at huge speeds, so there must be some limits and measures to ensure that tens of such huge wind turbines placed close together will not make too much ultrasonic issues (nois) and I'm interested in this more since those turbines are commercially available and sometimes govenments approves building such huge wild turbines too close to human houses, hoping nobody will punish them for high noise levels and landscape devastation  :--

It looks like, u  :bullshit: Beam is done, while hopefully they will not be able follow this quote  which could help them to handle those ultrasound issues :-DD
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If the facts don't fit the theory, change the facts
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Offline LabSpokane

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Re: The uBeam FAQ
« Reply #88 on: November 11, 2015, 05:46:05 AM »
Here's the chart for those who dislike linking:

 

Offline LabSpokane

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Re: The uBeam FAQ
« Reply #89 on: November 11, 2015, 05:54:20 AM »
Are any regulatory bodies really going to allow 155dB of sound (at any frequency) in public places?  Surely not?
Is there anything to stop that right now, or would fresh regulation be required? The health and safety legislation in most places only seems to specify maximum sound intensities for frequencies up to 6kHz or 8kHz. This seems weird, as a machine putting out 155dB at 10kHz is definitely a problem.

The chart I posted is an international standard, so I believe that for the North America and Europe, the sound level you question is clearly prohibited. 
 

Offline Fungus

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Re: The uBeam FAQ
« Reply #90 on: November 11, 2015, 06:27:05 AM »
It must be regulated somehow, while giant wind turbine farms can make ultrasound too,  while its wing end passes the air at huge speeds

Nope. Wind turbines aren't giant propellers. The blades aren't pushing on the air, the air is pushing on the blade. You'd be surprised how quiet they are when you stand right under one.

The whole 'wind farms make me sick' brigade pretty much belongs in the same camp as the "wifi makes me sick' brigade. Attempts have been made to record any sound at all in the houses of the affected but I don't think anybody's managed it yet.
 

Offline LabSpokane

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Re: The uBeam FAQ
« Reply #91 on: November 11, 2015, 06:34:15 AM »
uBeam is ultrasound-based.

Wind turbine noise is supposedly classified as "infrasound."

They are two totally opposite ends of the sound "spectrum" as it were.  Let's not clutter this thread up with wind turbine debates.
 

Offline eneuro

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Re: The uBeam FAQ
« Reply #92 on: November 11, 2015, 07:52:14 AM »
Wind turbine noise is supposedly classified as "infrasound."
Nope, it dependa how far away and wind turbine manufacture details:

PDF: Ultrasound emissions from wind turbines as a potential attractant to bats: a preliminary investigation

Quote
This preliminary investigation recorded ultrasound from only a limited sample of wind turbines.
...
Potential sources of ultrasound from wind turbines include 1) ultrasound generated like a whistle from rotors moving through the air, 2) electronic components, and 3) mechanical components. The transmission and generator components of wind turbines do not turn with rotational speeds at which the generation of ultrasound would be expected. However, loss of lubrication on moving surfaces could occasionally result in ultrasound generation, but the maintenance schedules of the turbines would limit or avoid such occurrences.

Now imagine, ultrasound levels in u  :bullshit: Beam ... reflected from so many places where its bloody devices operates... disaster for bats population  :--
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Offline georgesmith

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Re: The uBeam FAQ
« Reply #93 on: November 11, 2015, 01:28:46 PM »
 

Offline EEVblog

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Re: The uBeam FAQ
« Reply #94 on: November 11, 2015, 02:07:30 PM »
From:
New followup article by Garrett Reim: UBeam’s Disclosure Raises New Questions, Doesn’t Answer Old Ones

Quote
Furthermore, if uBeam’s receiver is not perpendicular to the ultrasonic beam, additional energy would fall out of focus and be wasted, experts said. In the TechCrunch blog post, uBeam also acknowledged it could not transmit through cloth or human flesh, meaning it would have difficulty charging a cellphone in your pocket or in hand.

“Presumably, the receiver surface is on the back of the phone where your hand is, so that’s going to cover that up,” said Pompei.

In essence, it appears an uBeam-equipped cellphone could only receive a trickle charge while flipped face down in your hand or on a table. That might make the system less useful than a PowerMat or Qi near-field wireless charging system, which charge face up.

And therein lies the major problem. Even if it is safe, efficient, low cost etc, no one is going to want have to charge their phone face down.
It's just a completely flawed idea that is forever being pushed backward into a never ending pocket of impracticality.
 

Offline LabSpokane

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Re: The uBeam FAQ
« Reply #95 on: November 11, 2015, 03:23:56 PM »
And therein lies the major problem. Even if it is safe, efficient, low cost etc, no one is going to want have to charge their phone face down.

Don't say such things before you've seen the secret prototype:



There's plenty of surface area there for transducers and the display is perfectly visible while sitting on the table. 
« Last Edit: November 11, 2015, 03:25:32 PM by LabSpokane »
 

Offline JimRemington

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Re: The uBeam FAQ
« Reply #96 on: November 11, 2015, 03:33:00 PM »
I believe there is a possible "green" aspect to the proposed technology that has not been discussed.

Given the rather large expenditure of power involved in transmitting the ultrasonic beams (offsetting the losses to air) perhaps coffee shops that embrace the technology would not have to heat their establishments in winter.
 

Online coppice

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Re: The uBeam FAQ
« Reply #97 on: November 11, 2015, 04:52:40 PM »
I believe there is a possible "green" aspect to the proposed technology that has not been discussed.

Given the rather large expenditure of power involved in transmitting the ultrasonic beams (offsetting the losses to air) perhaps coffee shops that embrace the technology would not have to heat their establishments in winter.
Where I live coffee shops don't heat their establishments in winter, and they might need to uprate their air cons to deal with ubeams in the spring, summer and autumn.
 

Offline eneuro

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Re: The uBeam FAQ
« Reply #98 on: November 11, 2015, 08:55:18 PM »
I believe there is a possible "green" aspect to the proposed technology that has not been discussed.
Yep, they could use their breakthrougth ultrasound transducers tracking technolgy to... kill mosquitos from the sky at the yard like this laser :-DD

New laser zaps mosquitoes out of the air


But this is my idea disclousued right now at EEVBlog, so I think it can be used as prior art if Mrs Perry wanted patent this, so she have to have another great dream if she wants make profit, else the only way to earn something on u  :bullshit: Beam will be The 25th First Annual Ig Nobel Prize Ceremony

Quote
"The 25th First Annual Ig Nobel Prize Ceremony introduced ten new Ig Nobel Prize winners - Each has done something that makes people laugh then think"

But hey showed results of his work to win this price, so there is huge difference and probably no chance for u  :bullshit: Beam win even this  :palm:
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Offline zapta

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Re: The uBeam FAQ
« Reply #99 on: November 13, 2015, 12:23:47 PM »
Nope. Wind turbines aren't giant propellers. The blades aren't pushing on the air, the air is pushing on the blade. You'd be surprised how quiet they are when you stand right under one.

The whole 'wind farms make me sick' brigade pretty much belongs in the same camp as the "wifi makes me sick' brigade. Attempts have been made to record any sound at all in the houses of the affected but I don't think anybody's managed it yet.

You should watch Windfall. Last time I checked it was on Netflix.
Drain the swamp.
 


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