The milestone marks the last major step in the development of the 76-turbine Pen y Cymoedd Wind Energy project in South Wales.
The Jones Bros Balfour Beatty joint venture will now focus on removing its cabins and equipment and reinstatement of the welfare compound area.
The joint venture was contracted to deliver the construction civil and electrical works for Vattenfall’s flagship Pen y Cymoedd Wind Energy Project.
Eryl Roberts, joint venture project manager, said: “All turbines, track, and crane pads have been handed over to Vattenfall.
“It’s been an incredible three years for everyone working on this huge project and the finish line is in sight.
“We will be clearing our compound of the cabins and equipment over the next few weeks. We’ll also complete any remaining snagging and reinstatement work to the client’s satisfaction.
“There will be approximately 25 joint venture workers on site during this period.”
The civil works for the project began in February 2014, with the joint venture leading on the construction of the concrete foundations for the 76 turbines, the laying of 56km of electrical cables, and the installation and upgrading of 80km of access tracks.
More than 70 per cent of all plant operatives have been sourced from within 30 miles of the Pen y Cymoedd site, and a total of 12 apprentices have been employed as part of the project.
The Siemens turbines have been specially selected to maximise the amount of energy generated. The turbine foundations required between 520m³ and 610m³ of concrete. A total of 6000t of reinforcement was used.
The Pen y Cymoedd Wind Energy Project will be the largest onshore wind farm in England and Wales, and when fully completed it is expected to generate enough electricity to power 140,000 homes.