REG will erect five 2MW Vestas V80 GridStreamer turbines at its Sancton Hill site, which was granted planning consent in February.
The turbines have now been ordered and are scheduled for delivery in spring 2012. They are expected to be operational in the first half of 2012, producing 27GWh of output a year.
Local residents had campaigned against the scheme, arguing that it would ruin the Yorkshire Wolds scenery.
REG chief executive officer Andrew Whalley said: "Sancton Hill has an excellent wind resource and this project will increase REG's renewable energy output by 25% to around 133GWh per annum and increase total capacity to 51.15MW. We are delighted to be working with Vestas again as their turbines are performing extremely well on a number of our operational sites."