# Stray Microwave Energy Collection

#### WM1205

Joined Dec 10, 2018
7
Hi, I have often thought that it may be possible to collect energy from the air literally given the tremendous amount of microwave radiation Transmission across the globe. A real application of NicloaTesla's "Power Tower's" could this be possible and what useable voltages and amperages can one expect? Also what materials would work best?

#### nsaspook

Joined Aug 27, 2009
7,482
How much energy do you think can be collected? NicloaTesla's "Power Tower's" didn't work and will never work using his misguided understanding of RF energy.

#### WM1205

Joined Dec 10, 2018
7
That is a great yet the "golden question" and as for the lack of function is the basis of my question as there were very little microwave energies traveling in the atmosphere at that time other than naturally occurring microwaves and localized RF radiation in the form of civilian and military RF sources where as today you practically cannot see 30 feet without seeing some sort of microwave radiation device including the phone I am typing this response.

#### SLK001

Joined Nov 29, 2011
1,548
You would be better served capturing energy from moonlight - much more energy there.

#### Papabravo

Joined Feb 24, 2006
14,250
The typical power levels available from the HF bands, 3-30MHz, is approximately -80 to -140 dBm. In case you are not familiar with that terminology it is dB with respect to 1 milliwatt. The middle of that range is -110 dBm. 11 orders of magnitude smaller than 1 milliwatt is about 10 femtowatts. At those power levels 10 nanoamps at 1 microvolt could be possible. Are you sure you want to work with such insignificant quantities.

So you say, well 3-30 MHz is not microwaves. That is true, but recovering power from microwaves is orders of magnitude more difficult. Try your hand at circuits you can actually build before trying to swing for the fences.

#### Alec_t

Joined Sep 17, 2013
11,532
If there were usable amounts of microwave energy to be harvested methinks your insides would have been cooked already .

#### Papabravo

Joined Feb 24, 2006
14,250
If there were usable amounts of microwave energy to be harvested methinks your insides would have been cooked already .
What a comforting thought. At least my brains will be scrambled before that happens -- by FEMTOWATTS!

As a side note you might be interested to know that the solar irradiance of the Earth's surface is 1,361 watts/m^2. That's 21 orders of magnitude more than a FEMTOWATT!

Last edited:

#### oz93666

Joined Sep 7, 2010
737
If you were living very close to a cell phone antenna this would definitely be possible cover the wall nearest the mast with coils of wire ... they would cast a shadow , the antenna would be forced to increase output when communicating with phones in the shadow , increasing your harvest.

#### BBee

Joined Dec 6, 2018
35
I have a vague idea of remembering from years back the electricity companies being worried about people collecting energy free from their high voltage distribution system. Even at low frequency, with high voltage distribution there is a field which can be accessed. You have efficetively an air cored transformer when putting a winding in parallel to a high voltage line.

Tracy

#### spinnaker

Joined Oct 29, 2009
7,835
Wrap a huge coil directly around the local broadcasting station's antenna and you might have something. Though something makes me thing they would object to such a project.

#### nsaspook

Joined Aug 27, 2009
7,482
I have a vague idea of remembering from years back the electricity companies being worried about people collecting energy free from their high voltage distribution system. Even at low frequency, with high voltage distribution there is a field which can be accessed. You have efficetively an air cored transformer when putting a winding in parallel to a high voltage line.

Tracy
It's not 'free', that would be stealing.

#### spinnaker

Joined Oct 29, 2009
7,835
Here is a question I was thinking about. How much energy is absorbed by var
It's not 'free', that would be stealing.

But isn't it wasted energy anyway?

#### nsaspook

Joined Aug 27, 2009
7,482
Here is a question I was thinking about. How much energy is absorbed by var

But isn't it wasted energy anyway?
No, it's not. The energy required for the physical line impedance is stored in this 'near' field (like a unloaded transformer secondary). It's not like far field radiation from a transmitter distant from the receiver. Any local reactive field tapped will be supplied with real energy that would normally be sent to consumers. The var losses are from real resistance mainly from the 'extra' current needed to build the reactive fields in the power lines. The energy in the reactive field not lost from resistance just circulates round and round without dissipating.

Last edited:

#### WM1205

Joined Dec 10, 2018
7
I've done experiments with moon power. Even in perfect conditions it's maybe 20uW from a large solar panel.
I have tried this too, I fabricated a large SP array of Aluminum angle Iron and set it atop an old satellite dish pier, using a cobbled together tracker from an old telescope (Celestron) mounted in the center of the rig with fresnel lenses (various distances and angles) I recovered from the scrap yard I was able to charge a bank of batteries however after a 2 month period the batteries were in not so good condition perhaps bc they had come from the scrapyard as well (some cells were shorted in a 6v 75Ah configuration). I lack the necessary funds to utilize new 2.7v 100Ah batteries

It's not 'free', that would be stealing.
So it is my understanding that If the Air coil is situated in your theoretical air space then you would simply be collecting and disposing of free electrons that the power company is willingly dumping on your property?

Last edited by a moderator:

#### nsaspook

Joined Aug 27, 2009
7,482
I have tried this too, I fabricated a large SP array of Aluminum angle Iron and set it atop an old satellite dish pier, using a cobbled together tracker from an old telescope (Celestron) mounted in the center of the rig with fresnel lenses (various distances and angles) I recovered from the scrap yard I was able to charge a bank of batteries however after a 2 month period the batteries were in not so good condition perhaps bc they had come from the scrapyard as well (some cells were shorted in a 6v 75Ah configuration). I lack the necessary funds to utilize new 2.7v 100Ah batteries
I don't think you tried it with moon power.

This is the main solar array for my experimental system.

#### nsaspook

Joined Aug 27, 2009
7,482
So it is my understanding that If the Air coil is situated in your theoretical air space then you would simply be collecting and disposing of free electrons that the power company is willingly dumping on your property?

There are NO free electrons being dumped anywhere in the electrical transmission system and even if they did electrons don't carry energy in the transmission system. There are EM fields that move energy from A to B and tapping those fields with the air coil is the same electrically as connecting a transformer to the lines to tap energy. The power company doesn't usually care because the amount of power is negligible and most people have the common sense to stay from high voltage power lines.

Joined Jan 15, 2015
5,612
When I was a kid, about 10 years old I strung a dipole antenna and built a crystal radio ( cat whisker) and eventually replaced my chunk of rock with a 1N34 Germanium diode. No power but with only my antenna I could clearly hear WHLI in my headphones. I noticed that when I placed my antenna lead on a cold water pipe (my ground) I saw tiny sparks. At age 10 this was a monumental discovery, I had found free electricity. Shortly after I discovered my new found free electricity couldn't do anything. After letting me chase my dream my father was nice enough to try and explain why. The worst part was the WHLI only played classical music. Whli was only about 1.5 miles away too.

Ron

#### WM1205

Joined Dec 10, 2018
7