how to generate (electronic energy from static energy?
Understand where losses can occur.

If you have any questions on this simulated model, it will help you understand the losses that occur over time and during a discharge.  

Properties of materials are most important to learn for insulators are Rs and Rp as well as common property of charge Q=CV.   Realize that all insulators are dielectrics with some electrode or "bushing" or surface resistance, Rs and self leakage, Rp.

Energy stored \$E=1/2 CV^2 [farad.volt^2]\$  [=watt-seconds=Joules]

The gap between the charged dielectrics ionizes according to E field and gradient (smooth/sharp) approx 1~3[V/um] in air at STP ( standard temp &amp; pressure) The kinetic energy of the lighter e- particles hitting the other conducting surface and the energy released hitting the wall is proportional to the energy and temperature of light and resistance, Ri or ESRi is inversely proportional to current. Thus since losses are I^2R , loss increases with current.







simulate this circuit &ndash; Schematic created using CircuitLab

For example Electrolytic caps have an C*ESR=T range from a few &lt;1us to &lt;10us ultralow ESR, &lt;100us low ESR >1ms high ESR large mF types.

Plastic caps are much better but lower charge density , d dielectric constant, thus bigger size.

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When contacts transfer charge from one capacitance to another, air will ionize and breakdown at some threshold around 1~3V/um (or 1~3kV/mm) and then air goes from open circuit with some pF value to low resistance  just before conductor contact is made in picoseconds ( like finger ESD) or nanoseconds or microseconds ( like lightning surges)

This may not be visible on even a 1GHz scope but this resistance contributes to some loss of energy.  In slow motion, just before contact, the air dielectric breaks down, then voltage drops instantly or folds back with this negative slope.  

The analogy is like an SCR switch which triggers at 1.2V at the gate then it's twin terminals conduct or like a DIAC shown in the chart which has only 2 terminals or like some tiny Neon gas tubes which trigger at ~80V and then drop in voltage.  These devices all have different characteristics yet share similar VI zig-zag shapes in the transfer function. 

If the electric filed is rising between contacts just before the BreakDown Voltage (BDV) is reached, the air can quickly ionize, with a sudden arc where the the voltage across the contacts drops suddenly with rising current. This is has a negative V vs I slope and is called negative resistance by ionization , an example of the avalanche effect. (see Arrow left + slightly up)  , whereas a linear biased BJT has a continuous negative resistance which gives it voltage gain in a common emitter. 

My only point is to allow you understand when you experiment , you can easily understand leakage from parallel resistance and choose large ceramic or plastic film caps with long time constants but harder to see and understand is that the action of contact resistance with a preceding arc that will occur for slow moving contacts.  When the ionization starts, electron emission releases energy, just before contact is made then may be a visible arc or not if low current, so I showed a bipolar light emitting diode to symbolize this arc.  Although strictly speaking LED's do not have negative resistance like Tunnel Diodes , it was the only symbol on this schema tool. (weak apology)


  But on a small scale you can transfer some small energy, but it is very small as along as it is used before self-leakage time. 


I just wanted you to understand the mechanics of electrostatic energy transfer has some losses.

This transfer loss characteristic is one of the fundamental reasons why lightning energy cannot be harnessed into batteries or capacitors and limitation materials to dissipate these losses with the magnitude of energy in one bolt.