Carries babies, consuming energy (5)
I believe the answer is:
totes
'carries' is the definition.
(toting is a kind of carrying)
'babies consuming energy' is the wordplay.
'babies' becomes 'tots' (tot can mean a young child).
'consuming' is an insertion indicator.
'energy' becomes 'e' (physics symbol as in E=mc2).
'tots' enclosing 'e' is 'TOTES'.
(Other definitions for totes that I've seen before include "Carries the betting system" , "Carries, drags" , "Carries or shoulders" , "Bears" , "Carries, lugs" .)