Is it possible to harness energy from the earths magneic field?

In summary, it is possible to generate electricity using a magnetic field, but it is not practical or worth the effort. The local military research group for the magnetosphere, HAARP, is also up to something. It would be ideal for electric vehicles if we could make batteries lighter weight. Wireless recharging coupled with autos carrying multiple (lighter weight) batteries (2 to 5) could solve the problem of range.
  • #1
nuts2546
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The other day I pondered the possibility of harnessing energy from a magnetic field. I was thinkin about windfarms and wondered if a similar process could be created with a fan made of a suitable material in a vacuum. Using the Earths Magnetic field as the Energy Source. Any ideas people??.:confused:
 
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  • #2
Keeping in mind that the Earth's magnetic field is very weak, it is possible to create a generator simply by moving a conductor through it. It wouldn't likely be worth the effort and expense, though. I seem to recall that someone actually tried it a long time ago, but I'm not sure.
 
  • #3
What mass of conducting wire would you need to pass through 1m (perpendicular to a uniform field of the same strength as the Earths, for simplicity) to generate 1A in the Earth's magnetic (B?) field?
 
  • #4
We'd still need to move the wire, which would require some sort of external force, like wind or water. And we're not at a shortage of magnetic fields, either. Permenant magnets can be much stronger than the Earth's field anyways, and aren't really that expensive or rare.

Am I correct on that?
 
  • #5
Correct. The Earth's magnetic field is far too weak to be useful in this respect.
 
  • #6
You cannot get "free energy," period. Magnetic fields are not a "source" of energy, though by investing energy in pushing a wire through a magnetic field, one can produce electricity.

- Warren
 
  • #7
NASA tried this with the space shuttle, extending a very long coil of wire out of the shuttle to let the vehicle's orbital motion through the magnetic field produce some of the juice needed to run instruments aboardship. But the tether broke as soon as ti reached its full length, and just kept going.

http://www.phy6.org/earthmag/wtether.htm
 
  • #8
Up here in Alaska, there's quite a bit of research involved with the ionosphere and magnetosphere (the ionosphere is a layer of particles that I assume are carried by the magnetosphere on the inner layer of it, closest to earth).

While it can't be used for power, the military here has a high interest in its uses for communication and some conspiracy theorists claim it can be used to wipe out enemy communications (by sending some sort of explosion into the ionosphere).

Anyway, here's a page on http://en.wikipedia.org/wiki/HAARP" , the local military research group for the magnetosphere, there's even a controversy section for the conspiracy theorists!

(not that I don't suspect the militairy-industrial complex is always up to something.)
 
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  • #9
there was an experiment with an italian satelite on a tether, connected to the space shuttle. It generated a pretty high current, and a spark ended up breaking the tether, and the satelite was lost. The tether was like at least 10 milese long or something, it was visible from the ground.

Theres also an idea to use the magnetosphere to boost spacecraft into higher orbits, or even to send them to the moon. Because if there is a charge on the wire, the wire will feel a torque, so the wire can be powered by solar panels on one side, and on the spacecraft would be on the other side. It's like using the sun's radiation and the Earth's magnetic field as propulsion.
 
  • #11
Ask the Sun to send a flare in our direction:

http://science.nasa.gov/headlines/y2008/06may_carringtonflare.htm

Even more disconcerting, telegraph systems worldwide went haywire. Spark discharges shocked telegraph operators and set the telegraph paper on fire. Even when telegraphers disconnected the batteries powering the lines, aurora-induced electric currents in the wires still allowed messages to be transmitted.
 
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  • #12
aidil said:
Hi, just wanted to share... this here is a demo of wireless electricity. Gave me an idea... that if we could tune into our Earth's electromagnetic frequency, we might be able to use it to power up our tools. http://www.ted.com/talks/lang/eng/eric_giler_demos_wireless_electricity.html

I love it when ideas merge.

As a side note, this video was also available next to your posted video. http://www.ted.com/talks/shai_agassi_on_electric_cars.html

The idea of wireless power - with a "working" range of 1 meter would be ideal for EV's. The highway system in the US is ideal for wind, solar and (yes I'll go there again) static collection/conversion. We can easily deploy power to the highway system - maybe even enhance the overall power grid in the process. The real challenge is to make batteries light(er) weight.

Wireless recharging coupled with autos carrying multiple (lighter weight) batteries (2 to 5) could solve the problem of range. By employing multiple on-board batteries, the vehicle could run on 1 battery and simultaneously recharge the others during travel - and switch electronically as needed.
 
  • #13
The idea of wireless power - with a "working" range of 1 meter would be ideal for EV's.

Why not put a coil around the outside of a house.
The magnetic field generated by electricity traveling through that coil will be the same at any point inside that coil. This magnetic field can then be used to power anything you want.
And you wouldn't have to use a big external coil. Just put a lot of turns on the internal coil to give you a higher voltage.

Doing this durring the construction phase of the house would be easy. Tie it directly into the mains feed to the house.

60 Hz on the exterior coil. Minimal loss unless there is a load on the internal coil. In which case the load would be what is used.

You wouldn't be able to travel too far outside of the plane of the coil, but if you put one coil on each floor, you should be fine.
 
  • #14
I live in an area where the most intelligent thing to come out of most people mouths is 'Pass me that there katchup'... that's right. KATCHUP not ketchup...that always bugs me for some reason... anyway. I was ecstatic when I found this forum. I had an idea a while ago about possibly combining the speed of an object made of a frictionless( or at least very friction resistant) material, moving at high velocity through our atmosphere while maintaining a VERY Low Earth Orbit and the properties of electro-magnetism and atmospheric static to generate enough energy to maintain the orbit and still have some left over. Possibly even some kind of conducting coil circling around the entire planet that would simply absorb and store the ambient energy in our atmosphere. If we went with the coil idea, the force of the rotation would hopefully help with the energy cost of keeping it up there and allow more energy collection. I haven't had much in the way of education in this field yet so I thought I would ask here. Is this feasible?
 
  • #15
I have pondered this many times. I came up with two ideas. Might they work?
The first, a coil buried around the northern hemisphere magnetically levitated and spun so that the solar wind travels through it.
The second, a coil around the entire Earth with a massive lobe. The coil should be lined up with the moons orbit so that the lobe would be pulled by the moons gravity. I guess this would slow the moons orbit and eventually crash it into the earth.
 
  • #16
johnnycactus said:
The first, a coil buried around the northern hemisphere magnetically levitated and spun so that the solar wind travels through it.

Care to explain this with a little more detail?
 
  • #17
The idea is a coil that is buried and encircles one of the poles at a diameter of say 500 miles. The coil could be levitated of floated in fluid or like a maglev train and either spun or moved vertically by changing buoyancy or alternating magnetic attraction/repulsion. Or if tuned the coil could be vibrated or waved with sound at a resonate frequency. Probably the south pole is better because of the existing land mass.
 
  • #18
johnnycactus said:
The idea is a coil that is buried and encircles one of the poles at a diameter of say 500 miles. The coil could be levitated of floated in fluid or like a maglev train and either spun or moved vertically by changing buoyancy or alternating magnetic attraction/repulsion. Or if tuned the coil could be vibrated or waved with sound at a resonate frequency. Probably the south pole is better because of the existing land mass.

The logistics might prove to be a challenge.
 
  • #19
How much energy is stored in the magnetic field of the earth?

As the magnetic field itself is always changing, would it be possible to harness that energy with a stationary coil?

How big would the coil have to be to produce a useable energy?
 
  • #20
nahkaimurrao said:
As the magnetic field itself is always changing,

But only very very slowly at any particular location.
 
  • #21
ah, but take into consideration, all these theories deal with the Earth's magnetic field in either air or a vacuum, but what i would like to know is what effect does salt water have on the Earth's magnetic field as it passes through it? I know salt water is an electrolyte, so wouldn't that magnify the field? also if the magnetic field gets stronger the closer you get to the core, wouldn't the ideal location for a collector coil be in a mine or at the bottom of an ocean trench, e.g. the Marianas Trench?
 
  • #22
johnnycactus said:
......The first, a coil buried around the northern hemisphere magnetically levitated and spun so that the solar wind travels through it...

The solar wind doesn't get to the Earth's surface let alone to anything buried below the surface


Dave
 
  • #23
itsallovernow said:
ah, but take into consideration, all these theories deal with the Earth's magnetic field in either air or a vacuum, but what i would like to know is what effect does salt water have on the Earth's magnetic field as it passes through it? I know salt water is an electrolyte, so wouldn't that magnify the field? also if the magnetic field gets stronger the closer you get to the core, wouldn't the ideal location for a collector coil be in a mine or at the bottom of an ocean trench, e.g. the Marianas Trench?

why would you think an electrolyte would increase the strength of a magnetic field

Dave
 
  • #24
jtbell said:
But only very very slowly at any particular location.

so true.

The only time there is a rapid ( and relatively short term) change is during times of "sudden impulses" caused by solar flares and coronal mass ejections CME's
These suddent impulses may last minutes to a few hours at the most


Dave
 

Related to Is it possible to harness energy from the earths magneic field?

1. Can we use the earth's magnetic field to generate electricity?

Yes, it is possible to harness energy from the earth's magnetic field to generate electricity. This concept is known as magnetic induction, which involves using a magnet and a coil of wire to create an electrical current.

2. How much energy can be harnessed from the earth's magnetic field?

The amount of energy that can be harnessed from the earth's magnetic field is relatively small compared to other renewable energy sources. However, it is estimated that the earth's magnetic field contains enough energy to power the entire world for hundreds of years.

3. What is the process of harnessing energy from the earth's magnetic field?

The process of harnessing energy from the earth's magnetic field involves using a device called a dynamo, which consists of a rotating magnet and a stationary coil of wire. As the magnet rotates, it creates a changing magnetic field which induces a current in the coil, producing electricity.

4. Are there any current technologies that use the earth's magnetic field for energy production?

Currently, there are no large-scale technologies that use the earth's magnetic field for energy production. However, there are some small-scale devices, such as magnetic generators, that claim to harness energy from the earth's magnetic field but their effectiveness is still under debate.

5. Are there any potential drawbacks or limitations to harnessing energy from the earth's magnetic field?

One potential drawback is that the earth's magnetic field is not constant and can fluctuate, making it difficult to maintain a steady and reliable source of energy. Additionally, the technology for harnessing energy from the earth's magnetic field is still in its early stages and may require further development and investment. Finally, the process of extracting energy from the earth's magnetic field may have some impacts on the environment, although these are not yet fully understood.

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