A specially built barge is steering the next stage in the development of tidal energy technology under test at EMEC, the Orkney-based European Marine Energy Centre.
Irish company OpenHydro has successfully used the unique vessel to mount a tidal turbine on the seabed off Eday.
Called the OpenHydro Installer, the twin-hulled barge has Kirkwall as its port of registry. Orkney Towage's tug HARALD towed the new vessel, complete with turbine, to the site at Eday.
Up to now, OpenHydro have been using a research platform to put prototype turbines through their paces at EMEC's tidal energy test site at the Fall of Warness, off Eday.
Earlier this year, one of the Open-Centre turbines fed electricity generated at sea into the National Grid – a key moment in the test programme and a first for the UK.
In future, OpenHydro's vision is to have these revolutionary machines deployed in farms under the world's oceans. So it has developed a system for placing the turbines directly on to the seabed.
"When we realised the type of vessel we needed wasn't available in the marine market place, we decided to build our own," said OpenHydro chief executive James Ives.
The barge has been constructed at a shipyard in Holland and is thought to be the first vessel of its kind ever built.
It is fitted with three powerful winches, which are used to lower turbines fitted with individual support rigs on to the seabed – where the technology converts energy from tidal currents into electricity.
"We've gained invaluable experience testing our prototype turbines at EMEC," added Mr Ives.
"The barge was conceived as a result of that experience and has been used to deploy a turbine for the first time at EMEC's tidal test site. So where better than Kirkwall as its port of registry."
EMEC managing director Neil Kermode said: "This is believed to be the world's first vessel to be built specially for deploying tidal turbines.
"It represents an important step forward on the journey towards harnessing the power of tidal currents as a significant and sustainable source of electricity.
"So we are delighted that it has been used for the first time in Orkney and that OpenHydro have chosen Kirkwall as the vessel's home port.
"Using Orkney Towage's tugs also worked well and once again showed the advantages of using local vessels and experience in these challenging conditions."
EMEC was established with around £15 million of funding from the Scottish Government, Highlands and Islands Enterprise, the Carbon Trust, the Department for Business, Enterprise and Regulatory Reform, Scottish Enterprise and Orkney Islands Council with support from the European Regional Development Fund under the Highlands & Islands HISTP programme.
The company also operates a wave energy test site in Atlantic waters off Stromness.