Tidal array cable laying project finalized

 
The final phase of a major project to investigate cost-effective methods of cable laying for tidal power arrays, with the aim of helping accelerate development of the marine energy industry, has been completed in Orkney.

Funded by Scottish Enterprise, the £2.4 million Tidal Array Cabling Solution project was launched in December 2013 to develop and demonstrate efficient methods of locating, securing, protecting and retrieving cables for tidal energy arrays.

Stromness-based energy and environmental consultancy Aquatera was one of a number of companies that took part in the initial concept development stage of the project in 2014, subsequently being awarded a contract to undertake two demonstration projects.

The second and final phase of the project was completed over the winter of 2015 at a specially licensed site in the fast moving tides of Hoy Sound in Orkney.

The project tested over 10 different technological and procedural innovations during cable laying trials.

The key areas of innovation included the type of cable lay vessel, the decking arrangements, the mooring arrangement and materials, surveying techniques, the use of a novel cable locating and protection system and the proving of cost effective cable layout and cable deployment and recovery techniques.

Daniel Wise, Head of Offshore Technology with Aquatera, said: “The results that we have achieved within just one year have been outstanding and give us real confidence that we can now further develop an approach to cabling design, cable laying and cable management that will transform the economics and reliability of tidal energy.”

Aquatera has led and managed the year long programme of design, fabrication, deployment, testing and reporting activities, with collaboration and support from Stromness-based Green Marine, who also provided the GM700L heavy lift barge.

The barge was adapted for use as a cable-laying platform using a movable modular decking system installed between the barge hulls. Other contractors in this second phase of the project included JGC, LUPUS, TTI, and Orcades Marine with Roving Eye, Sula and Triscom providing deployment support services.

To remind, the first phase of the project, completed last year, saw a team led by Aquatera deploy a 50 metre long, rigid ‘U-tube’ cabling protection structure – designed by Jee – at the European Marine Energy Centre’s (EMEC) Shapinsay Sound tidal test site in Orkney.

This is believed to be the longest fixed sub-sea structure in the world installed to date at a tidal site, with its deployment involving an innovative arrangement of vessels, EMEC’s press release reads.