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Comment by gabrielblack | Hacker News Reader

If someone reading the post here is thinking that will be possible give power to "small devices" using WIFI, that is not and will not be impossible. We are talking about few micro amperes when a coin cell battery can deliver 220.000 micro amperes, as paragon. There are some niche applications in micro ampere range, but in that cases there are some reliable and more stable solution, like cesium batteries. Dave of EEVBlog has a mission, debunk this wireless energy affirmation, explaining why it's simply impossible, for example: https://www.youtube.com/watch?v=P8s3Xjeg0sk

Moreover the power is related to the distance to the wifi source and the presence of an active WIFI obviously doing this kind of solution at least impractical even for ultra low power consumption applications. An Apple tag uses a coin battery and I think will use that solution for a veeeeery long time.

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So you provide a video of Dave showing the math that you can get only microwatts out of radio waves to debunk something that ... claims to provide power in the microwatts range?

The "charge a phone" thing is obviously bunk, but that's not what's discussed here.

Show me applications in microwatt range to justify the "usable", moreover you need a wifi. Why someone should use that instead of a solar cell, like the one on calculators ?

The title of this article was changed, by the administrators I guess, I think it's good in times where someone think opinions are more relevant then science.

this didn't claim to have anything to do with "common user"s. energy harvesting/storage for IoT-type nodes is of huge interest, with lots of work being done on it.

> Dave of EEVBlog has a mission

and i don't think he'd appreciate your "contribution" here to that mission.

I wrote it fast, I rewrote it. My point is that the title is misleading and suggest you can use WIFI radiation as power source to do something useful in the near future in consumer electronics. You simply will not.

you're the one who hallucinated "consumer" into all of this. nobody said that. it wasn't in the title. this isn't a consumer electronics forum.

as the abstract of the article points out, it's for energy harvesting applications. which have been demonstrated as being perfectly useful with microwatt collection rates.

The administrators changed the title of this article for a reason. Moreover, that device is intended to be installed very close to the "consumer", that is useful in medical application, for example, where is no advisable to install the battery in a device to be implanted in the body. So you can install the emitter , transmitter, whatever you want call it on the skin. And WIFI is total bullshit. The say "WIFI frequency" aka 2.4 GHZ because as we all known is the deregulated frequency reserved for consumer application. So, IMHO the researcher shouldn't have used that term, is confusing ! From there to say that the experiment involve the problem of powering cordless devices in the sense of electronic gadget is complete misunderstanding of the sense of that research. Man , science is not an opinion.

it kind of looks like you're having a rough day. i hope you feel better.

Simply I don't like fake news.

Maybe he’s right but his video is from “jan 2010”, maybe in 11 years some improvements are been made… and this research doesn’t talk about “power a smartphone” but a very very small device.

errata corrige: ... that is not and will not be possible.

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