Ocean Kinetics and Green Marine wrap up OpenHydro tidal platform decommissioning

Two Scottish companies, Ocean Kinetics and Green Marine, have completed the decommissioning of OpenHydro’s tidal energy platform at the European Marine Energy Centre (EMEC) in Orkney.

According to Ocean Kinetics, the decommissioning project managed under a contract with EMEC, involved dismantling the platform’s steel superstructure and pile foundations.

In April, Ocean Kinetics and Green Marine formed a joint venture to handle the project, combining expertise in operational engineering, cutting, and heavy-lift operations. The team utilized Ocean Kinetics’ divers, welders, and ROV services alongside Green Marine’s vessel, mooring, and cable expertise.

Key operations included removing two 18-ton steel piles grouted into the seabed. Ocean Kinetics noted that Reversed Diamond Wire Cutters were deployed to cut the piles flush with the seabed, aiming to restore the area to its original condition as closely as possible. The teams also completed cable disconnection and termination as part of the decommissioning effort.

“We are very pleased to have successfully completed this complex and wide-ranging project,” said Green Marine’s Operations Manager, Terry Norquay.

“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.”

Both companies bring experience in marine operations, from salvaging and decommissioning projects to aquaculture and port equipment services. Notably, they have managed tasks such as retrieving sunken barges weighing up to 1,000 tons and removing the 4,000-ton decommissioned Buchan Alpha oil rig.

Ocean Kinetics Marine Projects Manager, Roger Goudie, added: “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.”

OpenHydro was the first developer to use the tidal test site at the Fall of Warness off the island of Eday when it installed the test rig and the 250 kW open-centered turbine in 2006.

“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 fulfil 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,” said Neil Kermode, Managing Director at EMEC.

“Now that decommissioning has been completed, we can complete a full lifecycle analysis with valuable insights around marine operations, structural integrity of long-term deployments as well as 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 building out to tidal energy arrays.”

The OpenHydro was the first tidal turbine to be grid-connected in Scotland and subsequently the first to successfully generate electricity to the national grid in the UK. The test platform at the Fall of Warness test site was used to streamline its tidal turbine technology until its liquidation in 2018.

In July, the Scottish duo unveiled finishing the first phase of decommissioning of the tidal energy platform in the Orkney Islands.