The scheme at Fullabrook Down, near Barnstaple, will be installed despite local opposition. Energy minister Malcolm Wicks announced the decision at a British Wind Energy Association conference in Glasgow.
"Fullabrook Down will make a substantial contribution to meeting Devon's target of generating 151MW of renewable electricity by 2010," said Wicks.
He added that the forthcoming final planning policy statement on climate change will place more weight on renewable energy.
A government spokesman told Planning that the statement, which is due later this year, will encourage planning officers to look more favourably on applications for renewable energy.