Talladh-a-Bheithe Wind Farm Ltd, a subsidiary of Netherlands-based Eventus BV, wants to build 24 turbines on designated wild land in Perthshire between Loch Rannoch and Loch Ericht.
The scheme is opposed by the Mountaineering Council of Scotland (MCofS), the John Muir Trust and Scottish Natural Heritage, which says the proposal could affect “natural heritage interests of national importance”.
MSPs are due to debate the application at Holyrood tomorrow.
Ms Gabaldon’s novels feature the adventures of Second World War nurse Claire Randall, who is transported back to the Scotland of 1743.
They have been adapted for a 16-part television series which has attracted millions of viewers in the US and features iconic locations across Scotland.
The US-based author said: “Light-bulbs need energy; human souls need wildness and beauty.
“While I appreciate the need for sustainable energy development, I very much oppose such a project on Rannoch Moor.
“While I am a novelist and film consultant, I was in my previous career an ecologist - and in all three of those roles, I’d view the potential loss of Rannoch Moor’s unique wilderness ecosystem as a tragedy, a disaster that would not be worth any amount of extra kilowattage.”
MCofS says the development would affect views from more than 30 munros and corbetts, including Schiehallion, the Ben Alder massif, mountains above Glen Lyon, the Drumochter Hills and Buachaille Etive Mor.
David Gibson, MCofS chief officer, said: “Diana Gabaldon’s Outlander novels are loved in part because they capture the beauty and wildness of the Highlands.
“The immense success of her TV series shows how much people value our open landscapes and offer further evidence as to why we must not ruin what remains of our wild lands by turning them into industrial zones.
“Such places are at the heart of Scotland’s cultural identity and history, they are essential for our recreation, well-being and enjoyment. In economic terms, they are absolutely vital for our film and tourism industries.”