Take philosopher’s breath away with small energy generators (9)
I believe the answer is:
windmills
'generators' is the definition.
(windmill is a kind of generator)
'take philosopher's breath away with small energy' is the wordplay.
I cannot quite understand how this works, but
'philosopher's' could be 'mills' (John Stuart Mill) and 'mills' is found in the answer.
'breath' could be 'wind' (wind is a kind of breath) and 'wind' is found within the answer.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for windmills that I've seen before include "Grinders of flour" , "They're powered by moving air" , "Don Quixote tilted at these" , "They extract energy from moving air" .)