The deal is part of a supply agreement with Iberdrola also covering projects in Wales and Spain.
The Whitelee order is for 69 Eco 100 3MW and 6 Eco 74 1.67MW turbines, to be installed by May 2012. The contract includes transportation, commissioning and maintenance.
Alstom is hailing the deal as the first large scale project to use the Eco 100 turbine.
Whitelee, which is located in southern Scotland, currently has a 322MW capacity consisting of 140 Siemens 2.3MW turbines.
The wind farm found itself under the media spotlight after a blade on one of its Siemens 2.3MW turbines fell off in the middle of the night. As a result, Whitelee was switched off for over a week.
The incident happened in the early hours of March 19. Siemens said an examination of the broken blade revealed a "material defect in the laminate". The company said there could be the result of changes to the manufacturing process.