Top model every year ran out of energy (7)
I believe the answer is:
paragon
'top model' is the definition.
(the best example or model of something)
'every year ran out of energy' is the wordplay.
'every year' becomes 'pa' (per annum).
'out of' means one lot of letters goes inside another.
'energy' becomes 'go' (I've seen this in other clues**).
'ran' placed around 'go' is 'ragon'.
'pa'+'ragon'='PARAGON'
(Other definitions for paragon that I've seen before include "Model of conduct" , "A perfect person - pagan or what?" , "Exemplar" , "An ideal" , "Flawless model" .)