Foxygloves
No, no, no
The “connotations” of “beacon” seem to be entirely misrepresented. Nothing to do with carbon emissions!
I have no quarrel with using the Welsh version of the name as an option but do the environmentalists also wish to rename Beaconsfield, Minehead, Coalville.etc?
They do not see to understand the derivation of (Beacon” which comes from Old English bēacen, bēcen, bēcn “a sign, portent; a standard, banner; a signal, signal fire, signal hill or tower, watchtower; lighthouse.” )
The reason it was a fire long ago was, guess what, because they hadn’t invented LED bulbs 
It gets sillier by the day!
Does anyone remember climbing up local hills or mountains to light beacons when it was The Queen's Silver Jubilee?
It was quite thrilling to see the next beacon along being lit but rather alarming climbing down a Dartmoor Tor in the dark!