Powys County Council has refused plans for a wind farm near Llanbadarn Fynydd, in Radnorshire.
Developer RES says the Garreg Lwyd Hill Wind Farm proposal consists of 23 turbines, at a maximum height of 126.5m, which would generate enough electricity to power more than half of the homes in Powys.
It is located within an area designated by the Welsh Government for renewable energy development.
Members of the authority's planning committee have unanimously voted to refuse consent to the application today.
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