A £600 million interconnector is set to deliver a more flexible energy system for consumers in the UK and Belgium.
Nemo Link, which stretches 80 miles from Herdersbrug on the Belgian coast to Richborough in Kent, is a joint venture between National Grid and Belgian transmission system operator Elia. It is the UK's first subsea power cable to Belgium and will enable the trade of electricity between the UK and Belgium when it becomes operational in early 2019.
National Grid chief executive John Pettigrew believes interconnectors are a key tool in delivering a cleaner and smarter energy system for UK consumers,
He said: ""Nemo Link will bring great benefits to consumers in the UK and Belgium by offering both countries access to a broader energy mix and providing opportunities to expand into other electricity markets.
"This new connection will also provide significant social benefits. By connecting the UK and Belgian electricity markets, we will ensure customers have access to different sources of generation and lower priced electricity. This will mean that customers pay less for their energy.
"Over the next five years National Grid will be investing more than £2 billion in new interconnectors to Europe and our significant commitment is driven by the value that interconnectors like Nemo Link can bring to customers at both ends of the cable."
More than 1,400 engineers and project specialists have worked on the project since construction began in 2015. Once live the 1000 megawatt cable will provide access to enough energy to power one million homes.
Business and Energy Secretary Greg Clark said: "Nemo Link is the UK's first interconnector since 2012, increasing our electricity capacity from these power cables by a quarter and further enhancing security of supply for us and Belgium.
"Not only will this interconnector help us to accommodate more renewable energy on our grid and provide cheaper, greener energy for consumers as part of our modern Industrial Strategy, it will also see continued and close cooperation on energy across borders with our European partners."
Elia Chief Executive Chris Peeters said: "Today marks the inauguration of the first interconnector between Belgium and the United Kingdom. This massive project is a first for Belgium, both technically and strategically. This new interconnector - along with the soon to be completed ALEGrO connection with Germany - will enable us to significantly boost our energy exchange capacity and to position our infrastructure at the very heart of a future integrated European electricity system."
Nemo Link is National Grid's third interconnector to Europe following the success of IFA (Interconnexion France Angleterre), a 2000 megawatt interconnector which connects the UK to France, and BritNed which joins the UK to the Netherlands with 1000 megawatts capacity.
The company also has two more under construction, North Sea Link which will connect the UK and Norway and IFA 2 which will provide a second link to France. Both will add 1400 and 1000 megawatts of capacity respectively.