National Grid and Scottish Power face an investigation by the energy industry regulator after repeatedly bungling the startup of a £1.3bn subsea power cable which is supported by home energy billpayers.
The high-voltage power cable began transmitting renewable electricity from Scottish windfarms to homes and businesses in England and Wales in late 2017, about two years behind schedule.
Since then it has suffered multiple outages due to faults along the 530-mile power line, which runs from the west coast of Scotland to the north coast of Wales, and has spent most of this year offline.
Ofgem said it will review whether the joint venture set up by National Grid and Scottish Power breached their licence conditions by delivering the cable late. It will also examine potential breaches relating to the cable’s operation.
The cable is a key part of the UK’s plans to use more clean energy because it will help to channel Scotland’s abundant renewable energy to areas in the south that have higher demand for electricity.
When the cable is not operating there is a higher risk that windfarms may be paid to turn off, at a cost of millions of pounds to energy billpayers every week, to avoid overloading the local grids with more clean electricity than Scotland can use.
The cable project also helps Scotland to import electricity from the rest of the country when wind speeds are low.
In a joint statement the energy companies said they are confident that the project has delivered benefits to consumers since it began operating two years ago and will continue to “transport cleaner greener energy to our homes and businesses across Great Britain”.
The cable has been offline for two weeks following an outage caused by a fault on land near the southern end of the line.
“We are working hard to repair the current cable fault and are certain we will overcome these difficulties and establish a link that will continue to benefit consumers for many years to come,” the joint venture said.