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# Lightning Rod Power Generation

No Actual Lightning Used -- and that's a good thing
 (+5) [vote for, against]

Use a kite or a balloon to carry aloft a lightning rod. The tether for the kite or balloon would be made of something lightweight, electrically conducting, and electrically insulated. The rod would, of course, be connected to the conductor in the tether.

At ground level, the voltage difference between the tether's conductor and the earth is used to generate usable electricity.

Because the lightning rod continually depletes the surrounding air of electrical charge, it (hopefully) won't be struck.

 — goldbb, Apr 27 2010

Would need nice big diodes to cope with the wire depleting both positive and negative charge centres. BIG diodes indeed!
 — saedi, Apr 28 2010

It's not the size of your diodes, it's what you do with them.
 — FlyingToaster, Apr 28 2010

 How large does the surface of your lightning rod need to be in order to drain charge from the atmosphere at a useable rate?

Even if your collector was, say the size of a large cloud, it will still be subject to lightning stikes simply because it has the lowest charge of anything in the vicinity. This is demonstrated when we see lighning jump from one charge cloud to another.
 — Twizz, Apr 28 2010

 saedi, we are conducting electricity out of each cloud that flows around the lightning rod as the cloud flows around the rod. I know that the charge is unevenly distributed, and I assume that the charge is weakest near the edge.

 As the lightning rod enters the cloud, it should initially be exposed to a small charge. The tether will drain this electrical charge to the earth, causing what had been a low charge to be neutral... thus making that bit of cloud the new "edge" of the cloud's electrical charge.

 I'm visualizing the cloud's charge as a bowl-shaped puddle, and the lighning rod is sucking away the edge... if we can discharge the cloud's energy fast enough, we'll never be exposed to a high voltage.

 Twizz, It's not so much the surface of the lightning rod that depletes the charge from the air, but rather the number and spacing of sharp pointy bits.

 Also, when the rod depletes the cloud it's in of charge, it brings the cloud's charge towards zero, so that both the rod and the cloud it's in have a charge which is as neutral as possible.

 This will make that particular cloud the least likely to be struck by lightning, as current prefers to flow from strongly positive objects to strongly negative objects. So as long as the storm contains both positively charged clouds and negatively charged clouds, "our" cloud is safe, due to having a median charge.

 Of course if "our" cloud is surrounded by positively charged clouds, it's charge will be *relatively* negative, and if it's surrounded by negatively charged clouds, it's charge will be *relatively* positive, and thus it will be vulnerable to being struck.

Thus, I will concede that the system will need to be protected by a lightning arrester... but I don't think it will be frequently activated.
 — goldbb, Apr 28 2010

//lightning arrester// ... I really doubt you can make lightning freeze, bitch! Hand over your weapons!
 — daseva, Apr 28 2010

 //I know that the charge is unevenly distributed, and I assume that the charge is weakest near the edge.//

 Charge accumulates on the outer surface of a charged conductor. See: Van de Graaff generator, Kelvin's Thunderstorm.

Does this apply to clouds? I dunno. Maybe not, if charges are being separated within the cloud itself. I know very little about electrically charged clouds.
 — Wrongfellow, Apr 28 2010

Don't let that stop you giving your opinion ... it would be a dangerous precedent.
 — 8th of 7, Apr 29 2010

What's happening in the form of magnetism in a charge brewing cloud?
 — wjt, Apr 29 2010

at risk of buggering up an idea that I like, we have done this before, though perhaps in annos.
 — FlyingToaster, Apr 29 2010

 I see this as extending the charged edge of cloud to very close to the ground.

 I think the reverse would be true. Discharging the cloud fast would create currents and magnetic fields down the tether which would lower the resistance to a strike. Slowly leaking the charge down the line as if the cloud was just building more charge would try to keep the clouds charge seperation resistance.

 The edge of the cloud might not be gradual gradient of charge.

It would be good if the tether was topologically equivalent to the cloud. Made of a network of capacitors and resistors, this corded network acts electronically like a volume of cloud.
 — wjt, May 01 2010

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