Em 4/5/2012 11:24, Bob Axtell escreveu:
> On 5/3/2012 3:27 PM, Martin McCormick wrote:
>> Electron writes:
>>> Won't the return currents cause ionization in the terrain, etc.. possib=
ily
>>> with biological implications?
>> 	I just red the pdf on the link and it did say that the
>> return currents were around 1200 meters down. I know that
>> alternating current is successfully used in meggers which are
>> magneto-based ohm meters for measuring soil conductivity. I
>> don't know what would happen over a long period of current flow
>> but as long as there is not a DC component, the continuous
>> reversal seems to prevent ionization.
>>
>> 	Neon and fluorescent lamps last much longer running on
>> AC than they do on DC. Also, some en clinometers use an
>> electrolyte in a sealed tube and they can be damaged by DC but
>> work fine on AC.
>>
>> Martin McCormick
>> WB5AGZ
> I also read the PDF thoroughly. I am inclined to consider the idea of=20
> transmitting
> power through ground as unsound.
>
> I see that, in theory, current will pass through the ground. But will it=
=20
> do so reliably?
> Wouldn't the fact that soil holds a varying amount of moisture cause a=20
> differing
> amount of conductivity? Wouldn't two metal poles placed in the ground 3'=
=20
> deep
> and 50' apart measure a very different conductivity at night vs during=20
> the day,
> because of the daytime evaporation of surface soil water?
>
> Who says that the current flows deep under the ground (i.e., 1200m)? Why=
=20
> doesn't
> it take the path of least resistance, like current normally does (I've=20
> never seen it do
> otherwise in my entire life)?


Why could not at 1200m deep the conductivity be maximal? Perhaps rocks
full of metal ore, soaked in water?


Isaac


--=20
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