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[TowerTalk] Comments on Lighting from a non-expert

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Subject: [TowerTalk] Comments on Lighting from a non-expert
From: (Tom Rauch)
Date: Wed, 03 Jun 1998 17:22:32 +0000
To: <>
> Date:          Wed, 03 Jun 1998 13:20:31 -0400 (EDT)
> From:
> Subject:       Re: [TowerTalk] Comments on Lighting from a non-expert
> To:  ,, 

Hi Steve,

>       Isn't this the purpose of a porcupine static charge dissipated? 

So far as I know, it is the purported purpose of using this device 
in a different application than it's original design use on an 
aircraft flying THROUGH the clouds.

> on the tower, this device provides many points of contact with the cloud 

With my 200 ft tower, most clouds are too far away for such coupling 
except during a strike. It might work on a tower that reaches into 
the clouds (like an airplane does) but not on my stubby little 
tower. ;-)

> its charge as it passes by. Being mounted to the tower and the tower ground
> system, most of the charge is bled directly to ground before it causes a
> leader from the cloud. 

So if we measured the huge potential difference between the cloud and 
earth, this teeny-tiny ion cloud would be transporting enough charges 
to make a significant change in charge differences between those 
distant systems?

We certainly could visualize that effect.
If we add up all the energy in the corona discharge creating that 
tiny ion cloud,  and compare that energy over time to the amount of 
energy released in a lightning strike over the duration of the 
strike, they would have to somewhat compare to each other in 
intensity in order for any change in potential difference to take 

That assumes of course that every ionized molecule or any free 
electrons created in the air somehow drifts up to the cloud 
thousands of feet away *without* forming an ionized  leader.  


Now let's picture how much energy is stored. Visualize a power supply 
big enough to charge a cloud up enough to discharge to the earth once 
every ten or twenty minutes. The capacity of the cloud would be the 
energy storage, so all we need to do is trickle charge the cloud to a 
the few volts required to start an arc from cloud to earth.

Could we charge that cloud every ten minutes or so by running our 
power supply into a spike way down near earth?    

Even without exact numbers, it doesn't seem likely to me the very 
tiny little current involved, even when integrated over hours and 
hours of time, could ever even remotely approach the energy released 
in a strike..or that the spike does an effective job of coupling 
charges to the cloud. 

>Even if it doesn't totally prevent a strike, the resultant strike is
> quite a bit less than if it were not partially dissipated. And since you
> already have the aforementioned ground system installed, the resultant damage
> is probably zero (Warning - many assumptions).

I think you are saying the ion cloud partially discharges the 
storm cloud. If so, there must be a path from tower and earth to 
cloud,  causing the potential between cloud and earth to decrease. 
Short of an actual strike, where is that path and how much current 
would have to flow in that path? How does that path work without 
forming a leader? 

If the cloud doesn't provide such a path, all we are really doing is 
moving things around in a very small area near the point of corona 
discharge. The towers direct or indirect path to earth, even through 
a high resistance, would quickly replenish any charges lost to 
corona, and I'd bet darned few of those charges would make it to the 
cloud.... unless the spike thing was on an airplane flying through 
the cloud.

73, Tom W8JI

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