The project is being developed by Cennergi, a 50-50 joint venture between Indian utility Tata Power and South Africa's second-biggest coal producer Exxaro.
Suzlon will supply 66 S97-2.1MW turbines for the project and aims to begin construction next year. In April it was revealed Suzlon was preferred supplier for the project.
Cennergi will initially focus on renewable energy projects in South Africa. The longer-term strategy is to create a balanced portfolio of generation assets.
Speaking about the deal, Suzlon South Africa CEO Silas Zimu said: "Suzlon continues to grow from strength to strength in the South African market. Our objective is to provide not only clean and green
energy, but also to create many jobs.
"This venture shows how a South African black empowered developer (Cennergi) partnered with a South African black empowered manufacturer (Suzlon) can ensure that the Government's commitments on wind energy are realised."
The Cennergi announcement comes as the South African government approved seven wind projects totalling 562MW as part of its second renewable energy tender.