The council has approved 14 of the 16 planned turbines, adding 36.8MW of capacity and bringing the total up to 101.8MW. The existing windfarm has 29 turbines and a generating capacity of 65MW.
A decision on the remaining two 2.3MW turbines that lie within Rochdale Metropolitan Borough Council has yet to be made.
The companies originally applied to build an additional 26 turbines in December last year, but scaled back plans to just 16 extra turbines in April in response to public feedback.
The reduction means the expansion is by less than 50MW and therefore no longer requires approval from the Planning Inspectorate as it is not considered to be a Nationally Significant Infrastructure Project.
The plans also include benefits for the local community including a long term restoration plan for the moorland, which will improve the water quality; build paths for pedestrians and horse riders linking wind farm access tracks to existing public rights of way; and offer up to £750,000 a year for local authorities in business rate retention and local jobs and order procurement.