The Lightning Foundry is a project to build the world's first machine capable of directly exploring the mysteries of natural lightning formation.

Lightning is electricity, but operates very differently from electrical discharges at the human scale. As lightning forms, it breaks through the air up to ten times easier than small-scale electric arcs, using tricks we don’t yet understand.  The problem of understanding "lightning initiation" still confounds world experts in the field.  

However, recent theories and a bizarre experimental accident suggest that laboratory-scale electric arcs start to gain lightning-like abilities once they grow past about 200ft in length.

Our goal is to build a machine that can generate arcs beyond this critical length, and find out what happens.

Elevation View

To accomplish this goal we plan to use two 10-story high Tesla Coils -- the largest ever built.  At full output power [around four million watts] the coil towers will fill an area the size of a football field with a continuous display of electrical discharges.  By carefully adjusting the drive voltage [up to 14 million volts] and the spacing of the towers, we intend to explore this mysterious region where normal electric arcs transform into lightning.

We’ve completed a fully functional 1:12 scale prototype for the Lightning Foundry, which we use to study the interactions between the two matched coils, and refine new design ideas.  The prototype twin coils often surprise us with wonderfully unexpected behavior, including a strong tendency to couple power wirelessly over large distances. We studied this odd ability in detail, and published a paper on wireless power transfer at the 2008 North American Power Symposium.


The 1:12 scale prototype has already performed at several public events including Maker Faire, The Robert Randall Home for Decrepit Mariners, and also at the Integratron, sponsored by the UCLA Art|Sci Center.  

Photo courtesy of Nick Bilton.

The Electrum Project provided us a rare opportunity to study long electrical discharges up close.  Electurm's unusual size allows a person to climb into the high voltage electrode while the sculpture operates at full power.  By physically touching the launch point of the discharges with fast current probes, we were able to capture detailed waveforms of discharges up to 50ft in length.


Viewed from just inches away, the 50 foot long discharges possess an unusually intricate structure and sound. From inside the sphere it's impossible to tell how far the arcs are reaching, although the immediate impression is that it they stretch from the tip of the wand towards infinity.

© Lightning On Demand 2011