The Clyde approval means SSE can add about 162MW to Clyde’s 350MW existing capacity, putting it in the front rank of largest UK onshore projects.
The utility said the exact extra capacity would depend on turbines used.
The existing Clyde plant was completed in 2011 using Siemens machines.
The Scottish government also consented the 69MW Dersalloch onshore wind farm, in South Ayrshire, being developed by Iberdrola-owned ScottishPower Renewables.
Scottish energy minister Fergus Ewing said: “As well as bringing benefits to the local community, the Clyde Extension will also benefit the wider region through the provision of a Local Community Fund.
“The community packages that have been offered by both these developers will bring considerable benefits to the local communities.”
