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Harvesting Energy From Radio Waves to Power Wearable Electronic Devices

An interesting article regarding researchers developing a charger to use the energy from radio waves.

I recall being told some 50 years ago of a case in Holland whereby someone built a trap circuit tuned to the frequency of a close by broadcast transmitter so as to power his property for free, but was caught after the radio station investigated what was causing the weak sector in their transmission pattern.

I tried Googling the incident, and whilst I did not find it, I did find another article regarding a couple of other energy thieves.

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The greatest electrical mind of the early 20th century has already solved this one.

How are RFID devices powered.

Science already knows what is and isn’t possible.


Wow. Who would have thought that someone would have thought to (re)invent the idea of radio waves inducing a voltage and current flow in a conductor.
Lets call it an antenna.

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If only it was that simple.

Anyhow, our cousins across the ditch are way ahead of us:

Well of course how did you think the tracking and control chips that come with COVID jabs are powered? Bill Gates is way ahead of us.


Not necessarily, this technology has been around for decades. It has a number a major problem…very inefficient over distance and very high emissions (such as EMF which explains some of the losses). Good luck to the NZ government and startup again proving what is already known.

Edit: it also appears the size of the antennas will also limit its usability…

But to give you an example, a one-square-meter (10.7-sq-ft) transmitter could send about 10 kW for about 10 meters (33 ft), but a 40-square-meter (430.5-sq-ft) transmitter could give you about a 30-km (18.6-mi) range, which is much more than we’d need for the vast majority of applications.

And losses about double that of traditional poles and wires…

Most of the loss is on the transmitting side. We’re using solid state for the transmitting side, and that’s essentially the same electronic elements you can find in any radar system, or even your microwave at home. Those are at the moment limited to around 70-percent efficiency.

Technically possible, likely. Practical or feasible, highly unlikely or no.

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Who needs to dig a pit for a hangi. Just dangle your pig on the end of a pole for 30 seconds. Perfectly microwaved pork, assuming it doesn’t explode all over the guests. :joy:

The clever thinking with the focussed microwave beam is how they hope to avoid cooking any object that strays into it’s path. Both microwaves and laser beams are vulnerable to weather effects, including diffraction. This will affect laser beams differently to microwave radiation. The beams are also vulnerable to moisture, dust, snow, rain… They don’t call NZ the land of the long white cloud for nothing.

The 40m expanse for the project site. Proof of concept?

I can’t help wondering if a solar panel and or wind generator with batteries might be a cheaper solution for delivering power to a remote NZ mountain top. Or any where remote in NZ.

For a nation which is on target to deliver Ultra Fast Broadband to 87% of the population by 2022; is anywhere in NZ really remote, or in need of outdated wireless technology?

Ultra Fast = 1Gbps or 1000 Mbps.

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