The first electricity from a £2.6bn wind farm in the Moray Firth has exported power to the National Grid.
One of the first of 84 turbines to be installed for the scheme, by a specialist "ship-on-legs" called Pacific Orca, was involved.
Once completed, the Beatrice Offshore Windfarm Ltd (Bowl) project will be capable of providing enough electricity for up to 450,000 homes.
It is expected to be fully operational by the end of 2019.
Situated about eight miles (13km) off the east Caithness coast, the completed project would be Scotland's largest offshore wind farm.
It is the largest offshore wind farm in the world built using jacket foundations. The jackets are also the deepest water-fixed foundations of any offshore wind farm.
Each weighs about 1,000 tonnes and is installed in water depths of up to 56m (183ft).
John Hill, Beatrice's project director, said: "We often talk about key milestones along a project's journey, and Beatrice has had quite a few to date. But to see the first turbine turning in the Moray Firth and to have reached first power safely, ahead of programme and on budget, is a fantastic achievement for everyone connected to the project.
"The project has already brought several benefits to the local community, the UK supply chain and, once completed, Beatrice will make a significant contribution to Scotland's ambitious renewable energy targets.
"As always, I would like to thank everyone involved in the project and the local community for their continued patience and support as we continue to build Beatrice."