> Date: Wed, 03 Jun 1998 13:20:31 -0400 (EDT)
> From: K7LXC@aol.com
> Subject: Re: [TowerTalk] Comments on Lighting from a non-expert
> To: firstname.lastname@example.org, email@example.com,
> 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
> 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
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
73, Tom W8JI
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