According to the planning application, the mast will have a “medium” impact on its environment, but the Brecon Beacons Park Society disagrees.
But Griffiths, born and bred in the valley, believes the mast is too high a price to pay.
The novelist Ian McEwan is among the 60 people who have objected to the proposal, which goes before the Brecon Beacons national park planning authority next month.
“I’d go ballistic if someone wanted to put a windfarm here but a 17.5-metre mast isn’t so high,” he said.