The last of the first of OpenHydro

The test rig for OpenHydro’s first tidal turbine is being decommissioned from the European Marine Energy Centre’s Fall of Warness off the island of Eday in the Orkneys.

OpenHydro, now gone as a tidal turbine company, built the rig in 2006 for its proof-of-concept 250kW turbine, and it has stood in the water ever since.

It has two steel columns set in the sea bed, up which the turbine could be slid for maintenance, plus steel superstructure across the top of the columns.

Ocean Kinetics and Green Marine (UK) formed a joint venture and won the contract to remove the superstructure, cut the piles down and lift away the scrap – OpenHydro’s marine licence called for the seabed to be returned to its original condition, with nothing protruding.

The contract also requires the undersea power cable to be disconnected and terminated.

“Work is currently being undertaken during Neap tides with water speeds approaching 6kts [~3m/s],” according to Green Marine. “Engineering teams are aiming to capitalise on slack tide windows, when the water changes direction and flows at 0.5m/s.”

OpenHydro’s plans were to have turbines sitting on the sea bed. The open-centered design has bearings and the generator around the outside.

Find the Green Marine UK website here, and the European Marine Energy Centre website here