Wireless Power

Juice Box

Diamond Member
Nov 7, 2003
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recently my friend have been on this kick that we will one day have wireless power, however knowing how power works, i feel it is impossible, what do you think?
 

Juice Box

Diamond Member
Nov 7, 2003
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im talking something completely controlled and not which would potentially cause harm to things in the way, like wireless networks
 

Tiamat

Lifer
Nov 25, 2003
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You mean something that delivers the typical 110 or 220 Vs... If there were, youd probably get cancer real fast with those beams shooting through your body 24/7
 

Geniere

Senior member
Sep 3, 2002
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To answer your question directly, yes it is possible to transmit energy via radio frequency electromagnetic radiation (EM). Due to the inverse square law for circular propagation and the hazards for a directional beam, it will never be possible for a power utility to use it in place of transmission lines.

What is being considered is a satellite with an enormous area of photo voltaic cells. The radiation from the sun is absorbed and converted to RF energy (like in a microwave oven). Via a directional antenna, the RF EM field is transmitted, than received by an antenna array on the earth?s surface. This RF energy will be converted at that point to 60hz and sent over standard transmission lines to your home. Living things would not survive a trip through the RF beamed from space.

A laser and the lower frequency maser also transmit EM radiation. Since the radiated beam is coherent, thereby non-divergent over relatively long distances, they may be a better choice for power transmission. Their efficiency is so poor that it is not going to happen in the near future.
 

PowerEngineer

Diamond Member
Oct 22, 2001
3,598
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This seems to be a recurring topic here.

By "wireless power" I presume you mean the delivery of energy via electromagnetic waves without transmission lines.

In one sense, you can say that we already have wireless power -- in that very small amounts of power are delivered to your radios and television sets through the electromagnetic waves by the radio/TV transmitters. Of course, it's the amplitude or frequency fluctuations imposed on the base wave that we really use in these applications. But it does give you something to think about; that 10,000 watt transmitter actually delivers very little power to your radio/TV. Why? Because the stength (i.e. power) of the wave decreases with the distance from the (point) source. If you make the charitable assumption that the transmitter radiates just horizontally, then that 10,000 watts travels out from the transmitter like ripples from a rock dropped in a pond. The farther out you go, the bigger the circle around which that 10,000 watts is spread. At one mile from the transmitter, the circumference of the circle will be over 33,000 feet. This means that a one foot antenna (perfectly aligned in the horizontal plane) can capture less than 1/3 of a watt!

Now the regular electrical power systems we're familiar with are also electromagnetic waves (at 60 Hz). The transmission lines (as well as the wiring in your house...or all the wires in your computer) can be thought of as wave guides that very effectively focus the waves down the length of the wire. That 10,000 watts that you start with at the generator travels down the wire with only small losses to the load connected at the other end of the wire.

It seems to me that we'll always need to use some way of focusing the power to flow from the point of production to the point of use. Allowing it to dissipate with distance is way too inefficient. Higher frequency waves (e.g. microwaves) can be focused for point-to-point transmission without wires. But at our current power system frequencies, wire wave guides can't be beat.
 

Runamile

Member
Nov 25, 2001
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Originally posted by: Geniere
To answer your question directly, yes it is possible to transmit energy via radio frequency electromagnetic radiation (EM). Due to the inverse square law for circular propagation and the hazards for a directional beam, it will never be possible for a power utility to use it in place of transmission lines.

What is being considered is a satellite with an enormous area of photo voltaic cells. The radiation from the sun is absorbed and converted to RF energy (like in a microwave oven). Via a directional antenna, the RF EM field is transmitted, than received by an antenna array on the earth?s surface. This RF energy will be converted at that point to 60hz and sent over standard transmission lines to your home.

DUH! I learned that one playing SimCity. We'll all have that one in about 2020! :D
 

pX

Golden Member
Feb 3, 2000
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Have you read Atlas Shrugged or something? This is what "John Galt" did...
 

gsellis

Diamond Member
Dec 4, 2003
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Cogman

Lifer
Sep 19, 2000
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really, saying wireless is a bad term, Tesla's invetions where wireless and with a bit of refining probibly could be controled fairly safly, being no diffrent then climbing up a high voltage line and grabbing a couple of them. The Microwave idea is also wire less. Again Wireless is a bad term for what your trying to describe. Maybe Remote electricity would be a better phrasing, though mwaves do still kindof fall under it, But anyways a technology that would allow you to pick up any electrical device, turn it on, and never worry about batteries. Well unfortunatly your friend is sadly mistaken, I doubt that will happen in the near future. Sure the technology will probibly come, but the application will be far and few and vastly unaccepted.

Why am I so negitive about it? Electricity is not free, and remote electricity would almost impossible to monitor. Sure it may come, But I do doubt that it will be accepted because it will probibly be installed for single buildings. Imagine the horror of looking at an electrical bill and finding out that your neighbor had been using large amounts of your electricity giving you a huge bill.


Nope, before it can be vastly accepted, Electricity needs to be nearly free, I mean like $.01 per every TerraWatt hour. And for it to be that cheep we need to build more effective power plants. Many fission plants would work very well and I would not be oppossed if the US where recieving 90% of its power from them, but sadly nuclear plants are vastly limited and the US currently only recieves 20% of its power from them. Very sad considering how fuel efficiant they are.

Really think about it, 1 bar of Uranium can power a plant for a couple of days and produce more power then Several Coal plants, And at the same time Those coal plants are using several tons of coal.
[/rant]
 
Jul 16, 2004
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Electricity will one day be free, my friend. It is inevitable. We're talking way into the future. After we free ourselves completely from fossil fuels and move onto low-maintmance perpetually renewable forms of power generation.

Fusion is a good example of an near-ideal power source. It has already been accomplished (very recently i believe), but at extremely low-efficiancy. We're talking so low that it used FAR, FAR more electricity to power the magnet system than it generated. Once fusion is perfected, there is little reason power wouldnt be provided for free by governments.

As far as energy though air, high school physics covers using waves to 'move' electrons in a remote wire. Of course everyone else has already let you in on the secret of Radio.
 

footbal07

Senior member
Apr 3, 2004
270
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do any of you have any good detailed resources for information on tesla and cold electricity. i kno its a little off topic but i have been interested in his work and have not been able to find much on how it works or experiments with it.
 

PowderBB3D

Senior member
May 23, 2004
549
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Originally posted by: Runamile
Originally posted by: Geniere
To answer your question directly, yes it is possible to transmit energy via radio frequency electromagnetic radiation (EM). Due to the inverse square law for circular propagation and the hazards for a directional beam, it will never be possible for a power utility to use it in place of transmission lines.

What is being considered is a satellite with an enormous area of photo voltaic cells. The radiation from the sun is absorbed and converted to RF energy (like in a microwave oven). Via a directional antenna, the RF EM field is transmitted, than received by an antenna array on the earth?s surface. This RF energy will be converted at that point to 60hz and sent over standard transmission lines to your home.

DUH! I learned that one playing SimCity. We'll all have that one in about 2020! :D


You stole my joke... *weep* :brokenheart:
 
Jul 16, 2004
81
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Originally posted by: footbal07
do any of you have any good detailed resources for information on tesla and cold electricity. i kno its a little off topic but i have been interested in his work and have not been able to find much on how it works or experiments with it.

I refuse to believe that you cant find any information on Tesla. His work is widely popular and taugh in public schools around the world. Google search for 'Tesla theories'.

As for Fusion, i have a few links. The basic theories are very simple: There is an energy release when atomic nuclei are fused. It is not difficult to fuse sub-atomic particles at extreme temperatures. The sun is a perfect example of a large fusion power plant. Cold fusion on the other hand is, in theory, safe enough to preform in a house or a car. Here are some articles:

What If Cold Fusion Is Real?
The Cold Fusion Times
Cold Fusion Research: A Report of the Energy Research Advisory Board to the United States Department of Energy - 11/1999
UCLA Attempt to Replicate the CETI Cold Fusion Experiment
United States National Renewable Energy Lab (NREL)
A Page of Cold Fusion Links

In case you truly cant find data on Nicola Tesla.... Nicola Tesla - Master Of Lightning (PBS Website)
 

footbal07

Senior member
Apr 3, 2004
270
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i meant information on teslas work on cold electricity not on him himself or cold fusion. cold electricity has to do with radiant energy which he had several patients on.
 

klaviernista

Member
May 28, 2004
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Originally posted by: gsellis
A powsat search was not remarkable. Guess the phrase did not catch on, but power satellite transmission was a hit. Try these:
http://techreports.larc.nasa.gov/ltrs/PDF/tm4496.pdf
http://www.spacefuture.com/archive/conceptual_study_of_a_solar_power_satellite_sps_2000.shtml


The space based microwave power transmitter has actually been patented. For those not interested in reading the article it consists of an enormous space based solar collector which transmits energy (via microwaves) collected from the sun to a huge satellite dish (the dish had a radius of something like 1km) on the earth.

Also, we already have wireless power transmission and have had that for many years. I.e. Radar antennas transmit small amounts of power wirtelessly. Specifically, the antennae sends out an RF wave. When the wave hits an object (i.e. an airplane) energy from the wave is transferred to the object and actually generates and electric field (an eddy current). Radio works the same way.

Though for all I know aside from the space based system descroibed above there is no known system for transmitting large quantities of useable power wirelessly (yet)
 

iwantanewcomputer

Diamond Member
Apr 4, 2004
5,045
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Originally posted by: Geniere
To answer your question directly, yes it is possible to transmit energy via radio frequency electromagnetic radiation (EM). Due to the inverse square law for circular propagation and the hazards for a directional beam, it will never be possible for a power utility to use it in place of transmission lines.

What is being considered is a satellite with an enormous area of photo voltaic cells. The radiation from the sun is absorbed and converted to RF energy (like in a microwave oven). Via a directional antenna, the RF EM field is transmitted, than received by an antenna array on the earth?s surface. This RF energy will be converted at that point to 60hz and sent over standard transmission lines to your home. Living things would not survive a trip through the RF beamed from space.

A laser and the lower frequency maser also transmit EM radiation. Since the radiated beam is coherent, thereby non-divergent over relatively long distances, they may be a better choice for power transmission. Their efficiency is so poor that it is not going to happen in the near future.

ever heard of the microwave power plants on sim city 2000? same thing
 

CSMR

Golden Member
Apr 24, 2004
1,376
2
81
Originally posted by: unlockthesource
Electricity will one day be free, my friend. It is inevitable. We're talking way into the future. After we free ourselves completely from fossil fuels and move onto low-maintmance perpetually renewable forms of power generation.<BR><BR>Fusion is a good example of an near-ideal power source. It has already been accomplished (very recently i believe), but at extremely low-efficiancy. We're talking so low that it used FAR, FAR more electricity to power the magnet system than it generated. Once fusion is perfected, there is little reason power wouldnt be provided for free by governments.
Fusion is not generally expected to be a cheap technology. Somewhat higher cost than current energy costs, if successful, is the expectation in the medium term. There are hardware costs of all forms of power, and such hardware will be produced only if expected revenue justifies it. No more reason to expect governments to provide this free than to expect them to pay for oil for free. Providing fuel for free is inefficient because:
1. It is a government expense and so requires higher taxes detrimental to the economy.
2. Demand will become very high, much higher than the economically efficient level.
 

DonPMitchell

Member
Aug 2, 2004
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0
Tesla proposed a wireless power scheme using a giant high-frequency transformer (a Tesla coil) tuned to resonate with the Earth. That is, tuned to create a standing-wave electrical oscillation on the Earth. Then similarly tuned coils could extract power.

He claimed to have demonstrated this in a laboratory in Colorado Springs in 1899, and he got a lot of money to build a 200 foot coil on Long Island. Eventually his funding dried up and he went bankrupt.

Tesla followers range from sensible admirers to extremely looney people, so beware of what you find on Google. I've read most of the books on him and his notebooks. He knew more EE than most "inventors", but his idea of wireless power was probably a total crock. Just like radio or microwave schemes, you would just lose all your energy by dissipation.
 

DonPMitchell

Member
Aug 2, 2004
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And by the way, fusion is pretty dirty. Deuterium + deuterium fusion can go one of two ways: Helium3 + a neutron, or Tritium + Protium. The intense neutron flux in a fusion reactor is a problem, it tends to make the whole device radioactive and causes weird materials failures (metals crumble and blister, etc). And radioactive tritium is also not something you would just pour down the drain, but you could feed it back into the fusion reactor. Oh man, will that baby be radioactive after a while though!

There are some new ideas about Thorium reactors that are interesting. There's a lot of Thorium in the ground, and its fissionable, but its much harder to build a reactor with it. The good news is that you cannot get a run-away explosive reaction with Thorium, so its safer in that regard.