Wow! I've never seen such a thing. Very cool indeed.
I was curious how they did that, and whether or not it was dangerous, so I did some googling.
Sounds like it's something amateurs would NOT want to fool around with.
The name of the group is "Lords of Lightning".
Not sure how long they've been around. The https://www.facebook.com/pg/LordsOfLightningUk/about/?ref=page_internal says 2011.