The net proceeds of the transaction will be used to reduce SSE’s net debt.

In the period since SSE and OVO agreed the sale in September 2019, the necessary regulatory approvals have been secured and joint integration planning has been undertaken to ensure a smooth transition for customers and c.8,000 employees.

Completion of the sale to OVO will allow SSE to strengthen its focus on delivering the low-carbon infrastructure needed to help the UK reach net-zero emissions.

Alistair Phillips-Davies, chief executive of SSE plc, said: “We are very pleased to be completing this transaction, which we firmly believe is the best outcome for the business, its customers and its employees.

“The sale is in line with our clear strategy, centred on developing, operating and owning renewable energy and electricity network assets, along with growing businesses complementary to this core. SSE enters the new decade as a more focused group, even better positioned to lead the low carbon transformation required to achieve the UK’s vital net zero commitment in the years to come.”

Stephen Fitzpatrick, CEO and founder of OVO, added: “Today is an exciting day. It marks the end of one chapter for OVO but, more importantly, the beginning of the next one together with the SSE Energy Services business. We started OVO with a bold ambition to do better for customers and have stayed true to that vision ever since.

“SSE’s history of excellence at scale combined with OVO’s innovative technology and our Plan Zero commitments mean that together, as one team, we can bring millions more people with us on our journey towards zero-carbon living.”