I thought of extreme conditions without sunlight as the main source of energy for an ecosystem. Winds can be found pretty much everywhere, from ocean currents to interstellar winds.
What kind of system would a lifeform require to harvest the winds?
Unnatural things (magic and bolstered laws of physics etc...) are allowed up to some unspecified extent.
Some people seem to have problem with lack of information so let me provide some.
#001 What kind of planet?
This planet is a cold and dark place. No sunlight, no chemical energy, no heat, etc.. Only wind for some unknown reason. The wind part is "pseudomagic" so let's skip it. My basis for this idea was the strong winds of Neptune.
#002 What kind of lifeform?
Really any kind of lifeform would be sufficient. I brought up this question because as far as I'm aware kinetic and chemical energy don't mix up really well and there are not any lifeforms on earth that directly use wind for energy source. Birds do use it to fly, but not for bodily functions while plantlife uses it to carry pollen and spores for fungi, but none of these are actual biological functions.