In the case of static electricity discharge, how can I calculate how much energy is given off (i.e., arrives at the recipient side)?

I was wondering about this the other day.... Here are some ideas:

 

1.) By the sound of the "crack" most static arcs make (to get a rough idea of the power) .. I went down a slide once and the static shock actually hurt.. The "crack" was so loud you could hear it on the other side of the park. (i wonder if this could work for lightning as well)?

 

2.) How about from the length of the static electric arc?

Paschen's law gives an indication of the potential

 

http://en.wikipedia.org/wiki/Paschen's_law

http://home.earthlink.net/~jimlux/hv/paschen.htm