The massive tidal turbine AK1000 has been installed in 35m (114.8ft) of water at a test site in Orkney.
Atlantis Resources unveiled the marine energy device at Invergordon ahead of it being shipped to Kirkwall.
Trials on the device will now be run at the European Marine Energy Centre test site off Eday.
The device stands 22.5m (73ft) tall, weighs 1,300 tonnes and has two sets of blades on a single unit. It could generate enough power for 1,000 homes.