Installation work on the site started in January and Vattenfall confirmed that the first 145m turbine has been installed.

The project is situated on land managed by Natural Resources Wales within Rhondda Cynon Taf and Neath Port Talbot.

Siemens plans to complete the turbine installation work by the end of this year with a further 75 turbines due to be installed.

Vattenfall Pen y Cymoedd wind energy farm project director Will Wason said: "There is still some way to go but I’m pleased that Siemens and the team have safely erected the first of 76 wind turbines."

"As Wales’s largest onshore wind farm, Pen y Cymoedd will have a big impact on annual carbon emissions and help secure home grown energy."

The project is expected to start operations later this year or in early 2017. It will generate enough energy to power about 140,000 homes in the UK per year, 10% of homes in Wales.

It will reduce more than 200,000 tonnes of C02 emissions per year based on Government assessments of carbon dioxide emissions per unit of power generated in 2013.

A joint venture of Jones Bros and Balfour Beatty is responsible for providing the civil works for the wind farm. The grid connection is being implemented by ABB.

Image: Vattenfall installing Siemens’ 145 meter wind turbine. Photo: Courtesy of Vatenfall.