Single Chimney Stack in Alcudia
If you mean the single chimney stack set back from the main Alcidia-Can Picafort road, near to the Muro Hospital and on the way to Sa Pobla, it is the Murterar Power Station.
It supplies lots of the power for the islad, except when it breaks down....like last Thursday when the island (and Menorca) were plunged into darkness! It seems that the electric storms caused a "double fault".
The single stack is not to be confused with the "double stack" near Alcudia Port, which is the old disused power station and which the Mallorca Government tell us is to become a huge science museum.
I hope this helps.
Cheers!
Frito