London | Normally when you see Origin Energy boss Frank Calabria out and about, he’s decked out in a dark suit and tie. But in London last week, the formality evaporated. He was playing it cool and casual, in chinos and a light crew-neck sweater.

He was probably just trying to adapt to his surroundings. Calabria had come to the London headquarters of Octopus Energy, a six-year-old company with a very tech-y, start-up vibe of coffee machines, cheeky branding and chill-out spaces.