Following the sale by EDF of its electricity distribution networks to the Cheung Kong Group (CKG), UK Power Networks took over the running of electricity distribution to eight million customers in London, the East of England and the South East on 1 November.
UK Power Networks will be responsible for distributing power through 170,000 kilometres of underground cables and overhead lines, and more than 130,000 substations.
It will continue to build on the skills base of its 5,500 employees across the network including those based at major office sites in London, Ipswich, Bury St Edmunds, Potters Bar, Crawley and Maidstone.
UK Power Networks chief executive Basil Scarsella (pictured) said: "Our priority is to maintain a safe, secure and sustainable power supply to eight million homes and businesses.
"We're proud to be taking over the running of Britain's biggest power network and plan to build on the solid base inherited from EDF Energy Networks, which has successfully managed and improved security of supply for millions of people and businesses.
"We have an important role to play in the lives of the communities we will be serving and our focus will be on making sure our customers get the best possible service.
"Our parent company, CKG, has a strong record in managing large infrastructure networks and we are confident that this expertise will help us to continue to put customers at the heart of everything we do.
"The Cheung Kong group (CKG) is the largest publicly-listed infrastructure company in Hong Kong with diversified investments in transportation, energy and water infrastructure-related businesses. Operating in Hong Kong, mainland China, Australia, the United Kingdom, Canada, New Zealand and the Philippines, it is a leading player in the global infrastructure arena.
EDF Energy will provide additional help during the transition for up to 18 months, to ensure a smooth handover.