5 ms·

Tesla: Art of Transmitting Electrical Energy through the Natural Mediums (1900)

107 points by hownottowrite 9y ago

deleted 9y ago
[deleted]
JoeAltmaier 9y ago
Most remarkable are the number of very modern patents that cite this one! How surgical instruments benefit from earth-transmission technology is beyond my understanding.
- bhousel 9y ago
  The patent helps sensitive equipment work (think like an EKG monitor) during a lightning storm.
Bud 9y ago
Wouldn't it be better to post a link to the full patent here, since the OCR quality is so bad that it's almost unreadable on Google's site? Here's that patent on the USPTO site: http://pdfpiw.uspto.gov/.piw?docid=00787412&PageNum=1&IDKey=C89A7D242A7E&HomeUrl=http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1%2526Sect2=HITOFF%2526d=PALL%2526p=1%2526u=%25252Fnetahtml%25252FPTO%25252Fsrchnum.htm%2526r=1%2526f=G%2526l=50%2526s1=0787412.PN.%2526OS=PN/0787412%2526RS=PN/0787412 http://pdfpiw.uspto.gov/.piw?docid=00787412&PageNum=1&IDKey=...
- Bromskloss 9y ago
  Why do they publish each page in a separate file? Here are all pages joined together: https://a.pomf.space/sgpnalxtzbae.pdf https://a.pomf.space/sgpnalxtzbae.pdf
  - panopticon 9y ago
    If you click the "Full Document" button on the left, it provides a single PDF. Why that's not the default behavior though...
coldcode 9y ago
Fascinating to read the text and know this was done nearly 120 years ago. Such an amazing genius.
- Johnythree 9y ago
  Actually, it wasn't done. Every one of his Earth Conduction attempts ended up a spectacular failure.
leggomylibro 9y ago
I started reading some of Tesla's speeches recently, and one thing that struck me was how he happily talks about enormous flaws in the implementations of his designs, but still went on to prove that they were POSSIBLE even if the practical design might have to wait. His idea for ultra-efficient high-voltage, high-frequency AC power lines is a good example. It would probably work, but his proposed system required liquid insulation on the wires; it would be important to keep gases out of the medium, and the slightest break in a solid insulation like rubber or silicone (or gutta-percha) could basically turn the wire into the business end of a tesla coil. So...I don't understand enough about the subject to say for sure, but we probably landed on 50-60Hz for a reason. I wonder why this one didn't wind up working out, but I'll bet it's described somewhere in the application which I've only skimmed. Also, for anyone else trying to dive into it, 'condenser' = 'capacitor' in olde-speak.
- andmarios 9y ago
  We already use high voltage for power transmission. Step up transformers at the power plant bring the voltage up to 230kV for transmission and step down transformers within the city bring the voltage down to normal. My guess for the frequency, is that it is a harder conversion to perform with acceptable loss. Compatibility reasons doesn't allow for just bumping it up. Also let's not forget that AC frequency actually comes from the revolutions per second the power generator does, so there may be some other physical limiting factors here. Last, some underground high power transmission lines are actually emerged into oil, to keep them cool.
  - andars 9y ago
    Higher frequency on power lines would be less efficient, not more. High voltage DC is the most efficient, but is most expensive because you can no longer use transformer for step-up and step-down.
- euroclydon 9y ago
  > we probably landed on 50-60Hz for a reason I'm pretty sure that's the minimum to prevent perceptible light flicker.
pjc50 9y ago
So this seems to be https://en.wikipedia.org/wiki/Extremely_low_frequency https://en.wikipedia.org/wiki/Extremely_low_frequency Including "The attenuation of ELF waves is so low that they can travel completely around the Earth several times before decaying to negligible amplitude, and thus waves radiated from a source in opposite directions circumnavigating the Earth on a great circle path interfere with each other.[20] At certain frequencies these oppositely directed waves are in phase and add (reinforce), causing standing waves. In other words, the closed spherical Earth-ionosphere cavity acts as a huge cavity resonator, enhancing ELF radiation at its resonant frequencies." Does anyone have a technical explainer of Tesla in modern terminology?
- m4x 9y ago
  Which of those terms do you not consider modern? As far as I know all those terms are still in cirulation Edit: sorry, I see you probably mean the content of the patent rather than the passage you quoted
romdev 9y ago
The wording reminds me of this whimsical story that I read several years ago (before Tesla motors), about the electric car that he powered with vacuum tubes and an antenna: http://keelynet.com/energy/teslcar.htm http://keelynet.com/energy/teslcar.htm Come to your own conclusions, but there's evidence that it was a hoax: https://en.wikipedia.org/wiki/Nikola_Tesla_electric_car_hoax https://en.wikipedia.org/wiki/Nikola_Tesla_electric_car_hoax
- 13of40 9y ago
  Something I've always wondered about is whether the electrical charge of the earth is uniform across the entire surface, or of you could harvest electrical power by just running a (presumably really long) wire between two grounded spots. I guess if they don't do it the answer is probably "no", "not enough to pay for the wire", or "Where do you put the meter?"
  - Johnythree 9y ago
    It is common knowledge that a pair Earth stakes will pick up a small amount of current. Hobbyists have been using the idea for years to run small radios. Likewise that same ground current will screw up Telegraphs (etc) which try to use an earth-return path. The problem for large scale energy harvesting is that the Earth is conductive, so any voltage differences are shorted out by the Earth itself and dissipated as heat. To put it another way, the Earth is a lossy medium, so any signals are heavily attenuated by distance.
DaniFong 9y ago
This is amazing

107 points by hownottowrite 9y ago

deleted 9y ago

[deleted]

Most remarkable are the number of very modern patents that cite this one! How surgical instruments benefit from earth-transmission technology is beyond my understanding.

bhousel 9y ago
The patent helps sensitive equipment work (think like an EKG monitor) during a lightning storm.

Bud 9y ago

Wouldn't it be better to post a link to the full patent here, since the OCR quality is so bad that it's almost unreadable on Google's site? Here's that patent on the USPTO site: http://pdfpiw.uspto.gov/.piw?docid=00787412&PageNum=1&IDKey=C89A7D242A7E&HomeUrl=http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1%2526Sect2=HITOFF%2526d=PALL%2526p=1%2526u=%25252Fnetahtml%25252FPTO%25252Fsrchnum.htm%2526r=1%2526f=G%2526l=50%2526s1=0787412.PN.%2526OS=PN/0787412%2526RS=PN/0787412 http://pdfpiw.uspto.gov/.piw?docid=00787412&PageNum=1&IDKey=...

Bromskloss 9y ago
Why do they publish each page in a separate file? Here are all pages joined together: https://a.pomf.space/sgpnalxtzbae.pdf https://a.pomf.space/sgpnalxtzbae.pdf
- panopticon 9y ago
  If you click the "Full Document" button on the left, it provides a single PDF. Why that's not the default behavior though...

coldcode 9y ago

Fascinating to read the text and know this was done nearly 120 years ago. Such an amazing genius.

Johnythree 9y ago
Actually, it wasn't done. Every one of his Earth Conduction attempts ended up a spectacular failure.

leggomylibro 9y ago

I started reading some of Tesla's speeches recently, and one thing that struck me was how he happily talks about enormous flaws in the implementations of his designs, but still went on to prove that they were POSSIBLE even if the practical design might have to wait. His idea for ultra-efficient high-voltage, high-frequency AC power lines is a good example. It would probably work, but his proposed system required liquid insulation on the wires; it would be important to keep gases out of the medium, and the slightest break in a solid insulation like rubber or silicone (or gutta-percha) could basically turn the wire into the business end of a tesla coil. So...I don't understand enough about the subject to say for sure, but we probably landed on 50-60Hz for a reason. I wonder why this one didn't wind up working out, but I'll bet it's described somewhere in the application which I've only skimmed. Also, for anyone else trying to dive into it, 'condenser' = 'capacitor' in olde-speak.

andmarios 9y ago
We already use high voltage for power transmission. Step up transformers at the power plant bring the voltage up to 230kV for transmission and step down transformers within the city bring the voltage down to normal. My guess for the frequency, is that it is a harder conversion to perform with acceptable loss. Compatibility reasons doesn't allow for just bumping it up. Also let's not forget that AC frequency actually comes from the revolutions per second the power generator does, so there may be some other physical limiting factors here. Last, some underground high power transmission lines are actually emerged into oil, to keep them cool.
- andars 9y ago
  Higher frequency on power lines would be less efficient, not more. High voltage DC is the most efficient, but is most expensive because you can no longer use transformer for step-up and step-down.
euroclydon 9y ago
> we probably landed on 50-60Hz for a reason I'm pretty sure that's the minimum to prevent perceptible light flicker.

pjc50 9y ago

So this seems to be https://en.wikipedia.org/wiki/Extremely_low_frequency https://en.wikipedia.org/wiki/Extremely_low_frequency Including "The attenuation of ELF waves is so low that they can travel completely around the Earth several times before decaying to negligible amplitude, and thus waves radiated from a source in opposite directions circumnavigating the Earth on a great circle path interfere with each other.[20] At certain frequencies these oppositely directed waves are in phase and add (reinforce), causing standing waves. In other words, the closed spherical Earth-ionosphere cavity acts as a huge cavity resonator, enhancing ELF radiation at its resonant frequencies." Does anyone have a technical explainer of Tesla in modern terminology?

m4x 9y ago
Which of those terms do you not consider modern? As far as I know all those terms are still in cirulation Edit: sorry, I see you probably mean the content of the patent rather than the passage you quoted

romdev 9y ago

The wording reminds me of this whimsical story that I read several years ago (before Tesla motors), about the electric car that he powered with vacuum tubes and an antenna: http://keelynet.com/energy/teslcar.htm http://keelynet.com/energy/teslcar.htm Come to your own conclusions, but there's evidence that it was a hoax: https://en.wikipedia.org/wiki/Nikola_Tesla_electric_car_hoax https://en.wikipedia.org/wiki/Nikola_Tesla_electric_car_hoax

13of40 9y ago
Something I've always wondered about is whether the electrical charge of the earth is uniform across the entire surface, or of you could harvest electrical power by just running a (presumably really long) wire between two grounded spots. I guess if they don't do it the answer is probably "no", "not enough to pay for the wire", or "Where do you put the meter?"
- Johnythree 9y ago
  It is common knowledge that a pair Earth stakes will pick up a small amount of current. Hobbyists have been using the idea for years to run small radios. Likewise that same ground current will screw up Telegraphs (etc) which try to use an earth-return path. The problem for large scale energy harvesting is that the Earth is conductive, so any voltage differences are shorted out by the Earth itself and dissipated as heat. To put it another way, the Earth is a lossy medium, so any signals are heavily attenuated by distance.

DaniFong 9y ago

This is amazing