High voltage sparks from dripping water

This home made machine, also know as Lord Kelvins Thunderstorm generates amazingly high voltage with dripping water!  In fact, the voltage becomes high enough to make sparks that discharge through a fairly large air gap. Once it gets started, it'll crackle with electricity every 30 seconds while the water is falling through it.

The construction is simple, 2 paint cans (Collectors), 2 pineapple cans (Inducers), Romex wire, a soda bottle, and some tinker toys to support a 2 liter soda bottle.  The two smaller pineapple cans (above) are the "inducers" which the water falls through on its way into the larger collecting paint can below.  The inducers and collectors are cross connected via the Romex wire as shown.  The Romex wire also holds the inducers in position above the collecting cans.

Unfortunately, all of today's paint cans are manufactured with a protective coating on their inner surface that must be scraped off so the charged water can be conducted to the can.  A wire wheel brush can be used to clean the inside of the cans if an insulating coating is present.    

Cross Connected Cans

As part of the setup, water is passed from above, through the inducers on the top and into the collecting cans below.  A two liter soda bottle is used as the water source.  Two holes are drilled in the bottom that provides the water streams.

A tinker toy structure can be used to suspend the water bottle above the cans.

Water bottle above cans

In preparation, fill the bottle about 1/4 way with tap water, and suspend it in the tinker toys.   To start the sparks, turn the two liter bottle 90 degrees so the holes face downward and the water drains into the cans below.

What makes it work?  Opposites attract!  Like most water, the water in the bottle contains both positive and negative ions.  As the charge builds up,  the positive inducer will attract the negatively charged water and collect it in the can below.  The negative inducer will attract positively charged water and collect it in the can below it.  This process will reinforce itself until the voltage is high enough to generate a spark.

The first attempt didn't work because the cans were sitting on the wood floor.  After putting them on top of a block of styrofoam, things started happening...    To mine and my kids amazement, sparks flew !!!

Seeing is believing...

Electricity!