Here are the "windmills" we are talking about. Five turbines, of "Vesta" design, capable of delivering a power of 1.125 MW together. They were built on Montaña de la Mina in 1991. Nowadays they are no longer in use.
From this cache you will see a wide panorama over Arrecife and around.
You can drive there with a car if you don't mind an unpaved road. Otherwise, You'd better park at the beginning of the track and continue on foot over around 400 meters.
Sources:
(+ thanks to mado-germany for the support)