Plans for an energy from waste incinerator at a quarry near Dartmoor have been rejected.
Waste firm Viridor wanted to build the plant at the New England Quarry south of Lee Mill on the A38.
But a report to Devon County Council raised concerns about the effect on the landscape, air and the River Yealm.
Viridor said it was disappointed by the decision as the quarry has been earmarked by the county council as a suitable waste site.
The firm initially put plans forward to the South West Devon Waste Partnership more than six years ago.
The partnership was created by Devon, Torbay and Plymouth councils to find a way of diverting waste away from landfill sites.
But many local organisations came out against it, including Dartmoor National Park Authority and about eight nearby parish councils.
Devon County Council's planning committee voted unanimously against the plans on Tuesday.
Viridor said the plant would deal with about 275,000 tonnes a year of the 2.5m tonnes of waste produced in Devon.
Two other incinerators are already being built, one in Plymouth and another in Exeter.
Howard Ellard from Viridor said: "We are very disappointed and it is a lost opportunity for Devon.
"We will contemplate our position and what we want to do next."
Charlotte Mills from campaign group EcoIVY said: "We're delighted. Viridor has no grounds for appeal.
"It's time for Viridor to concede defeat."