The secret to commanding lightning

“Mouths agape, a crowd stare at two men with lightning bolts firing from their heads and hands. I am at the Big Day Out, a music festival in Sydney, Australia, and touring alongside the likes of Iggy Pop and MIA are the Lords of Lightning.

The display is indeed stunning to watch. “It was like two wizards fighting,” says Toby, a Sydney hipster who quickly scampers back to the festival’s pounding music. Little did he wonder: how came these mere humans to create and command lightning?

The secret to the Lords’ power is Tesla Coils. The ones they use are two metres wide, on which they stand while thick blue bolts fly around them. First developed in 1891 by Nicola Tesla, a Tesla Coil is in fact two coils – one sitting inside the other. When an alternating current builds up in the smaller coil it creates a magnetic field that induces a current in the larger one.

In the show, one primary coil is wound around two secondary coils which service the two towers. This ensures both towers vibrate at the same frequency. Voltage in the larger coil can build up into millions of volts once the coils vibrate at precisely the same frequency. “That’s what causes the huge voltage rises that you see in the way of lightning,” says Carlos Van Camp, the creator of Lords of Lightning.

To ramp the voltage further, he winds the coils so the towers are pumped with opposing charges. “So, at maximum, one tower reaches two million volts and the other reaches negative two million,” says Van Camp. The massive voltage generated by the Tesla Coil rips surrounding air molecules into charged ions, allowing a current to flow through the air. This is similar to what it is believed happens in nature. While there is some debate, it’s believed that lightning is caused by the sudden release of charge from thunderclouds, which get electrically riled up by collisions between ice particles. Since most of the charge is negative, the ground becomes positive. Once the electric charge becomes large enough to ionise the air, a current will flow as a lightning bolt.

So, how can Van Camp stand atop these massively charged structures and walk away unscathed? He wears a conductive suit made of very small metal links connected together which protects him from the voltage. Electricity runs through the suit rather than through his body, and discharges out of his hands and head.

“If the suit has all the connections in place then you don’t feel anything,” says Van Camp. But, when there are loose connections electrical charges can move off track. When this happens, Van Camp says he can “feel little tingles to thumping shocks inside the suit”. But perhaps it is this danger that entices crowds.”

Read more at New Scientist