Greg Jackson has told the BBC that he remembers the power being cut off at home when he was a child. He runs one of Britain's biggest household energy suppliers now. The fact sits oddly beside the scale, and it explains a great deal.
He was born in September 1971, listed as Hanover in the infobox, and grew up in Halifax, West Yorkshire, then Saltburn-by-the-Sea. In the early 1980s he got into electronics and coding. At 16 he left school to program computer games. It was not a rebellion. It was work, and he liked it.
He did sixth form college, studied economics, and won a place at Pembroke College, Cambridge.
Then he went back. He did sixth form college, studied economics, and won a place at Pembroke College, Cambridge. It is the kind of path that makes admissions officers tell nice stories, but Jackson's was messier than the usual: a school-leaver programmer who returned to the classroom on his own terms.
By 30 he had owned or managed a number of small firms employing between four and 60 people. He founded e-commerce company C360 and telemedicine provider Consultant Connect, and sat on boards including peer-to-peer lender Zopa. Then he joined Octopus Group's idea of a new energy company. Octopus Energy was incorporated in October 2014 under the name Mercury Energy Supply, renamed in 2015, and began supplying customers that December.
What almost nobody notices is how deliberately it was built as software. The customer platform became Kraken, later licensed to other suppliers. In 2019 a campaign called Portraits from the Precipice appeared on more than 5,000 sites. In 2020 Origin Energy paid A$507 million for 20 percent, making Octopus a unicorn; Generation Investment Management came in at a 4.6 billion dollar valuation in 2021.
The real test arrived in 2022. When rival Bulb collapsed, Octopus took on 1.5 million of its customers. That was a rescue and a risk. By the end of 2024 it had overtaken British Gas as Britain's largest household supplier, though a net loss of 255 million pounds followed in 2025 on revenue of 13.7 billion.
In December 2025 Octopus said it would spin off Kraken at an 8.65 billion dollar valuation.
The quiet insight: a founder who has sat in a house where the lights went off treats the bill as a human problem, not a data one. Jackson built a company around the grudge, and then built the machine to serve it.