Octopus Energy has struck a deal to manage and supply power to more than 300,000 customers of Co-op Energy, Flow and GB Energy.

The deal, completed for an undisclosed sum, will see the Co-op brand retained and the Midcounties Co-operative retaining responsibility for customer acquisition as part of its wider utilities strategy, which now includes telecoms in addition to electricity and gas supply.

Customers of GB and Flow meanwhile will now become Octopus Energy customers.

So far this year Octopus has seen its customer base triple from 300,000 to more than a million.

The strategic partnership will also see the creation of a joint venture between the two organisations to develop the community-generated energy market in the UK.

Furthermore, the companies have announced, this joint venture will invest in projects, provide practical support to community groups and increase the volume of energy purchased from community schemes; encouraging more small-scale generation across the UK.

Midcounties Co-operative chief executive, Phil Ponsonby, said: “The Midcounties board is extremely proud of what has been achieved by our energy business since we entered a market dominated by just a few energy companies back in 2011.

“The market is now more competitive than ever, and it is clear to us that having the best technology is absolutely critical to delivering the best service to customers while maintaining a sustainable business for the longer term.

“Octopus have developed what we consider to be the most innovative and customer focussed technology anywhere in the industry today.

“But it isn’t just about technology, one of our strategic objectives is to make our members lives easier and our board was insistent that in looking for a partner, we found an organisation that shared our values, and put customers, colleagues and the environment at the heart of what they do.

“Octopus firmly meet these requirements and we are delighted to be partnering with them.”

Greg Jackson, chief executive of Octopus Energy, said: “This acquisition and our ongoing partnership with Midcounties is another step on the road to improving the domestic energy market for good.

“Our renewable energy supply and outstanding technology is now delivering award winning service to over a million homes in the UK with 100 per cent green electricity as standard. Co-op is one of the most well-respected British brands and we’re delighted to be working with them alongside our other cherished partners.

“I am also very excited about our joint venture for community energy. We have been hugely impressed by Co-op Energy’s achievement in this area and we believe that together we can help even more people from across the UK to come together in developing new sources of sustainable power.”

Greg Jackson, will be speaking at this year’s Utility Week Congress in Birmingham