More than two kilometres down a dark, dank tunnel deep inside a Norwegian mountain, the air is thick with dust and the smell of explosives. A pair of red laser beams pierce the blackness, providing guide marks for a drilling machine to bore a computer-programmed pattern of 30 holes into the rock. It forms a crucial part of National Grid’s key project: to build the world’s longest subsea power cable. Like a giant extension lead, the £1.4 billion, 450-mile North Sea Link interconnector will plug Britain into the Norwegian grid, enabling it to import 1.4 gigawatts of electricity, enough to power 750,000 homes. From Blyth in Northumberland, the cable will stretch across the North Sea before winding its way through 60 miles of fjords until the seabed comes to an abrupt halt on the far side of this mountain, 50 miles northeast of Stavanger. The cable will run through the tunnel, now close to completion, and then cross a lake to Kvilldal, home to Norway’s biggest hydroelectric power plant, where it will connect with the grid. While Britain is facing increasing challenges keeping the lights on as old coal and nuclear plants close and intermittent wind and solar take their place, plants such as Kvilldal mean that Norway’s grid is practically overflowing with cheap and reliable green power. “From a UK perspective, wind and volatility has picked up and has become a real headache,” Mr Williams, National Grid’s project director for North Sea Link, says. “These interconnectors can provide flexible services to support changes in output very quickly.” Britain has 4GW of interconnectors, but the government has backed the development of up to a further 9GW. Ofgem, the regulator, offers financial support through a new “cap and floor” system to guarantee domestic developers such as National Grid, which is building the link jointly with Statnett, its Norwegian counterpart, a minimum return.
Times 20th Feb 2017 read more »