OpenHydro was the first developer to use EMEC’s tidal test site at the Fall of Warness and became the first tidal turbine to be grid-connected in Scotland and the first to successfully generate electricity to the national grid in the UK.
The decommissioning project, contracted by EMEC, involved a range of marine services. A joint venture partnership was formed in April to deliver the contract, combining Ocean Kinetics’ divers, riggers, welders, and ROV services, and Green Marine’s offshore management, vessel, moorings, and cable experience, with shared responsibility for operational engineering, cutting, and heavy-lift operations.
Key work included dismantling the platform’s steel superstructure—including two 18-tonne steel piles drilled and grouted into the seabed—as well as cable disconnection and termination. Pile foundations were cut to the seabed using reversed Diamond Wire Cutters, returning the seabed as close as reasonably practicable to its original condition.
Green Marine’s Operations Manager, Terry Norquay, said: “We are very pleased to have successfully completed this complex and wide-ranging project. Significant planning was required to complete the recent phase involving the removal of the two 18-tonne steel piles, with our vessel, the Green Isle, positioned in a four-point mooring configuration to remain stationary and allow divers to safely enter the water.
“This project has expanded Green Marine’s broad portfolio of work and demonstrates the turnkey offshore decommissioning solutions we can deliver in partnership with our trusted colleagues.”
Ocean Kinetics Marine Projects Manager Roger Goudie said: “Working closely with Green Marine, we can deliver a full range of EPCI (engineering, procurement, construction and installation) contracts. There are few operators in the UK who can match our combined experience, reliability, and cost efficiency.”
Ocean Kinetics and Green Marine share vast experience in the marine sector, from work on subsea servers, port gates, and aquaculture equipment to retrieving sunken barges (reaching 1,000 tonnes in weight) and decommissioning projects, including the salvage and removal of the 4,000-tonne decommissioned oil rig Buchan Alpha.
Neil Kermode, EMEC Managing Director, said: “The OpenHydro platform stood at our Fall of Warness test site for 18 years, one of the longest tidal energy installations in the world to date. It’s great to see local Orkney and Shetland companies fulfill the decommissioning requirements, a testament to the world-leading supply chain capabilities that have built up here due to marine energy testing and demonstration activities. Now that decommissioning has been completed, we can complete a full lifecycle analysis with valuable insights into marine operations, the structural integrity of long-term deployments, and the impact of biofouling and corrosion. These lessons can help guide the tidal energy industry’s continued evolution as we ready our test sites for future clients and build out tidal energy arrays.”
OpenHydro tested seven generations of its turbine on the test rig at EMEC, the final version accruing over 10,000 hours of run time. In 2018, OpenHydro’s parent company, Naval Energies, halted investment in its tidal energy business, forcing the liquidation of the Irish-based subsidiary. Taking ownership of the assets remaining on its site, EMEC explored alternative R&D opportunities for using the platform; however, following a lifespan study of the platform, it decided to progress with decommissioning.
