How bright spark Giovanni Fili is recharging gadgets using ambient light

The Exeger CEO gives Andy Martin the lowdown on solar cells, self-charging headphones and ‘energy payback’ – plus a quick lesson in Swedish

Giovanni Fili in his factory in Stockholm (Exeger)

His headphones were sitting on the table in front of us. All the time we were talking the headphones were charging. But – and it is very big but – there were no wires. No plug, no socket. The headphones were just sitting there, quietly, discreetly, hoovering up photons and converting them into electrons.

I had gone to the Athenaeum hotel in Piccadilly to meet Giovanni Fili, CEO of Exeger, the Swedish company that has come up with a photovoltaic material generating pure energy out of ambient light, natural or artificial.

So, before you ask, no, it’s no good for your phone, because your phone spends most of the time in your pocket, where it’s normally fairly dark. But it’s good for all manner of other electronic equipment, whether it’s indoors or outdoors. I’m usually a bit of a sceptic, but I have to admit that the trick with the headphones knocked me out. I couldn’t have been more impressed if he had conjured up an elephant in the middle of Piccadilly. Or made one disappear.