A vital subsea cable linking renewables projects in the Western Isles to the mainland has suffered another setback, with developers saying there will be a further two-year delay.
Energy firm SSE has written to renewable developers on the Western Isles seeking formal confirmation that they plan to take forward their projects before actually commissioning the £750 million interconnector.
The project is being progressed by Scottish Hydro-Electric Transmission Ltd (Shetl), a division of energy giant SSE.
David Gardner, SSE’s Director of Transmission said: “We have been working on the case for a link to the Western Isles for around 10 years.
“In order for us to make progress through the regulatory approval process, which is designed to safeguard the interests of customers, we are seeking written confirmation from developers that their projects are viable.
“While the supply chain remains engaged, a new timetable, with an estimated completion date of 2019 has been provided.
“This factors in regulatory approval, which is estimated to take at least 15 months, and the manufacture of a cable, estimated to take around 18 months.”
Shetl will be working with developers to understand their position over the next month with the aim of incorporating a clear commitment from each developer into the case for the link, and addressing any concerns about the ability of the £750m project to demonstrate that it is in the interests of existing and future electricity consumers.
The subsea power cable would stretch to about 50 miles (80km) from Gravir on Lewis to Ullapool on the north-west coast of mainland Scotland. It would then connect to the controversial Beauly to Denny powerline to connect to the National Grid.
It is required because renewable energy projects planned for the Western Isles are expected to generate far more electricity than the needs of about 13,200 properties on the isles.
It would therefore be “exported” via the cable to the mainland for distribution.
There have been discussions about subsea cables linking islands energy projects with the UK mainland since 2001.
Western Isles Council - Comhairle nan Eilean Siar - had hoped Shetl would have had the interconnector in place this year. But the project has been dogged by delays and increases in estimated costs.
In a chicken and egg-like situation, Shetl has said construction work could not start unless the cost was underwritten by large companies planning renewable projects on the isles.
However, the projects face uncertainty because of high electricity transmission charges.
In 2010, Shetl said it had missed the deadline for ordering the cable to have it operational by an October 2013 target date.
Since then further delays have emerged. There were hopes to start work in 2015, but this was pushed back, and the cost of the cable also rose by 75% to over £700m.