The world's only grid-connected tidal energy testing site will take a significant step forward later this week with the arrival in Orkney of a specialised offshore construction vessel. The jack-up barge will be used to install the first tidal energy device to be tested at the European Marine Energy Centre (EMEC).

Dublin-based OpenHydro has developed a device consisting of a turbine on the seabed that will turn tidal currents into energy. The turbine will generate electricity for the National Grid, while undergoing a comprehensive test programme at EMEC's new Eday-based marine laboratory. 

The barge known as the Octopus is arriving in Orkney from France this week and will install the seabed mounted structure that will support the tidal turbine in fast flowing tidal currents at the Fall of Warness off the island of Eday. The 30-metre specialist barge has four legs that stand 26 metres above its deck while the barge is under tow. Once in position, the legs will be lowered on to the seabed lifting the barge out of the water to form a stable platform.

A three-legged frame assembled on Kirkwall Pier will then be lowered to the seabed using a 110-tonne crane standing on the platform. The frame will be used to guide the precision drilling operation that forms the next phase of the project.

The tidal turbine is currently being shipped to Orkney from OpenHydro's manufacturing base in Florida.

James Ives, OpenHydro's chief executive, said: "It will be the first grid connected tidal turbine in the UK and we are looking forward to starting the testing programme later this year. The turbine is one of the first tidal technologies in the world to reach the stage of permanent deployment at sea and is the accumulation of 10 years of design and development work."

Neil Kermode, EMEC's managing director, said: "This is a project that is both exciting and technically extremely challenging. The aim is to generate electricity for the grid by harnessing the power of the tides that flow around our shores.  In many ways this is a step into the unknown, but a huge effort in terms of planning and preparation has gone into ensuring the success of the project."

Open Hydro's main contractor, McLaughlin & Harvey, is being supported by a number of Orkney-based businesses, including Currie Brothers and Aquatera.