National Grid has inaugurated the UK’s first new interconnector in more than half a decade following the completion of construction work on the £600 million Nemo Link project.

The 1GW subsea cable stretches for 80 miles from Herdersbrug on the Belgian coast to Richborough in Kent. It is currently undergoing commissioning and is expected to become operational in early 2019.

Nemo Link has been developed by a joint venture between National Grid and the Belgian transmission system operator Elia.

“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,” said National Grid chief executive John Pettigrew.

“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.

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.”

More than 1,400 people have worked on the project since construction began in 2015.

Engineers discovered more than 1,200 potential unexploded objects, including mines and Second World War bombs, over 30 of which were detonated by Royal Navy divers. Other finds include a loaded 18th century cannon uncovered off the UK coast, which is now being restored by experts at Wessex Archaeology.

Nemo Link is the UK’s third electricity interconnector to continental Europe and the first to Belgium.

National Grid is planning to invest more than £2 billion in three new interconnectors over the next five years. The North Sea Link to Norway (1.4GW) and IFA2 to France (1GW) are already under construction and last month the company gave financial approval to the Viking Link to Denmark (1GW).