We know how to do it, it's just super inefficient.
this post was submitted on 09 Oct 2025
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It was basically omnidirectional high powered high frequency induction, wasn't it?
I think it also has a high chance to electrocute anything or anyone not grounded? At least that's what I gleaned from the old Nikola Tesla theoretical city-wide wireless power grid idea?
I think he was making great progress but the capitalists wanted to know where to put the meter and he was a genius among bean counters.
We've had wireless phone chargers for a long time.
Here's a demo of the tech from a while back:
https://www.ted.com/talks/eric_giler_a_demo_of_wireless_electricity
Well, we do. It is called "radio". There have been interesting cases of weird things happening in homes of people living close to strong radio transmitters.
After one person actually built a device to harvest this energy on a serious level, this was even made illegal here...
The downside is induced electric current in everything conductive within the transmission area.
oh
thats bad
Yeah, kind of a hazard, especially in a time when a lot of structures like bridges were made of iron.
Also you have the inverse square law issue - the energy imparted by the induction field drops off exponentially with distance, so the farther away you want to transmit power the higher the output transmission has to be, and it starts to get really impractical because the field strength varies significantly with distance from the transmitter. A device at the edge of the induction field will recieve a much lower amount of energy than a device in the middle. Assuming that you want to be able to run something useful (say, a refrigerator) at the edge of the field, well now you have to do something to shield similar devices that are closer to the transmission point or they'll melt - maybe you ground them so they can dump excess energy, but now you're wired again anyway, so what was the point of wireless power?
Wouldn't it be similar to radio waves where we can bounce them off the atmosphere and drastically increase their range?
Ah, no. Electromagnetic induction and electromagnetic radiation are related but different - induction doesn't produce radiation (radio) waves that would travel longer distances.
It is possible to power a device with radio waves - the most basic crystal radio just drives a speaker using the acquired radio signal. In 1945 the USSR "gifted" a concealed listening device (The Thing) to the US ambassador which worked this way - it was only "on" when an external radio was transmitting the correct frequency, making it very hard to detect. RFID tags also work the same - they don't require batteries because the chip is activated when the tag's antenna gets hit by the radio from the scanner.
This is only practical for very low-power devices, because transmitting high-power radio waves is dangerous.
It would likely be sufficient for things like smart wearables, though. Maybe even smart watches
Maybe, but then you run into difficulty with antenna size. An RFID chip uses a tiny antenna but it's only expected to work within a range of about 1cm. To make the listening device I linked above work with a radio source in another room required an antenna 23cm long.
I doubt you could ever transmit enough power to drive a display this way, at least not safely because the output from the transmitter would have to be orders of magnitude higher, and the circuitry on the receiving end would have to be bulkier as a consequence or risk overheating.
You mean the field drops off by the inverse square. Exponential drop off would be much faster.
Just make everything you don't want electricity in out of rubber.
From what I understand, if this technology would have been built out during his time then humanity most likely wouldn’t have developed our semi-processor/radio/computer/telephone technology because the wireless transmission of electricity would have prevented the earliest versions of that tech to work and we wouldn’t have been able to follow that line of technology progression.
I have doubts about this because wireless induction is extremely inefficient due to the inverse square law, and pumping out enough power to make it useful at a distance would electrify almost everything conductive.
No doubt it would have done that as well; I’m not saying he figured it out, that it would have worked or would have been efficient.
I have had this come up a few times over the years and it usually results in the other party inferring “but Tesla had it working in his lab” or “Edison killed the tech” type of response even after stating what you did.
They usually don’t get it until you explain that radio would have not been possible with that much ambient electricity in the air. That all the technology in your cell phone would not have been possible if radio tech was DOA because everything conductive, including rudimentary electronics, would be fried instantly in such a world. It wouldn’t be good for humans either in a world like that.
End. Thread.
Tesla was a genius, not a magician.
Dude, no way!
Thank you for this. I love this story but could never find it again after I read it the first time!
So grateful for the link to this, thanks again stranger!
That's awesome! Glad to help out.
Like that other guy said, as far as my memory goes as to the reality, and mathematical theory, the method is vastly more inefficient in just transmitting power. Material science is generally a better area of research given everything.
Oh and the whole this method of transmission of power is entirely incompatible with our modern world thing plays a part why its not much considered anymore. As far as I know of course.
He explained it all to his wife before his death, but she refused to share the key points with other scientists.
Mostly because others realized how impractical it would be.
Sure, why not? It's not like we're using the EM spectrum for anything else ..
He did a lot of ether . either is possible.