Comment on Researcher has developed, at a cost of less than one dollar, a wireless light switch that runs without batteries, can be installed anywhere on a wall and could reduce the cost of wiring a house by ...

FlyingSquid@lemmy.world ⁨1⁩ ⁨year⁩ ago

• DreadPotato@sopuli.xyz ⁨1⁩ ⁨year⁩ ago

  Last time i saw a product claiming to run on energy harvested from radio-waves, it was a kickstarter project that (surprise surprise) turned out to be a complete scam.

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  • luthis@lemmy.nz ⁨1⁩ ⁨year⁩ ago

    It is totally possible to harvest energy from radio waves, it’s just such a tiny amount that you could barely light a LED

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    • DreadPotato@sopuli.xyz ⁨1⁩ ⁨year⁩ ago

      Yeah that’s my point, the energy you can actually harvest is ridiculously small. Even if it was slowing charging a capacitor with this harvested power and saving it for later use, how often can i use the switch before depleting the energy faster than it charges? “oh sorry, you’ll have to wait 5min to turn on your lights again, It’s not quite charged enough”

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      • luthis@lemmy.nz ⁨1⁩ ⁨year⁩ ago

        My guess is you would get a couple seconds of light before needing several hours to charge it up again.

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• orclev@lemmy.world ⁨1⁩ ⁨year⁩ ago

  Not really. RFID operates the same way and has been around forever at this point. This whole thing is a gimmick, it doesn’t replace switches it just makes them more complicated and moves where they’re located. To switch mains current you’re going to need a relay which is more expensive than a simple switch and then you’re going to need to somehow tie a particular RF switch to the appropriate relay.

  Sure you might be able to reduce the length of wire running through the walls a tiny bit, but that’s going to be offset by a significantly more expensive and complicated control circuit somewhere. The only way this makes financial sense is if the cost of copper gets so high that running an extra 50 feet of wire is more expensive than a series of microcontrollers and relays and the unreliability of using RF for control.

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• helenslunch@feddit.nl ⁨1⁩ ⁨year⁩ ago

  If true, that application goes WAY beyond light switches. Really burying the lede here.

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• BrianTheeBiscuiteer@lemmy.world ⁨1⁩ ⁨year⁩ ago

  I’ve heard of this before but I think it’s really a trickle charge. Not practical for charging a phone or anything like that.

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• dgriffith@aussie.zone ⁨1⁩ ⁨year⁩ ago

  I have a Philips Hue wireless switch that has no batteries. The click action when you press the button is enough to drive the transmitter. The button moves in about 4-5mm when pressed.

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