Wind Dependant

This is the "Singing Ringing Tree" - a 3-metre-tall, wind-powered musical sculpture made of galvanised steel pipes standing high above Burnley. The pipes swirl to form the shape of a tree bent and blown by the wind, and they produce an eerie, melodious hum as the constant wind on Crown Point drifts through them.
In the background is Coal Clough Wind Farm consisting of 8 turbines, each 110 metres tall (almost 40 times the height of the 'tree') built by Scottish Power.
Both need the wind in order to function.