I found an interesting article on zpenergy.com about a very simple setup to charge batteries using atmospheric charge. I wonder how it will work when scaled up. Here is the article:
http://www.zpenergy.com/modules.php?name=News&file=article&sid=2534
It will work in some degree.
However, if you want to make it useable, more you try, higher the chances to ?catch? a lightning.
It?s not a ?catch by chance?. Actually, such an installation provokes and attracts them. So take good care!
Atmospheric current is (if I remember correctly) in the range of 2pA/sqm.
In order to have a decent 1 mA, according to a simple math you need to cover a surface of 5000 hectares (!!!). (That?s 5E8 square meters.) Still interested?
Good news is that voltage is high and you can increase de current by down-transforming the voltage. Still, the power is very small and the risks of being hit by lightning are high.
Respectfully,
Tinu
Also referenced on KeelyNet (just for info). :-\