Energetic person flipping lots during party (6)
I believe the answer is:
dynamo
'energetic person' is the definition.
(I've seen this before)
'flipping lots during party' is the wordplay.
'flipping' is a reversal indicator.
'lots' becomes 'many' (many means lots of something).
'during' is an insertion indicator.
'party' becomes 'do' (do is a kind of party).
'many' reversed gives 'ynam'.
'ynam' inserted inside 'do' is 'DYNAMO'.
(Other definitions for dynamo that I've seen before include "Small generator" , "Generator (sometimes 'human'?)" , "Forceful person" , "Monday (anag)" , "Producer of electrical energy" .)