Infest new divan with energy (6)
I believe the answer is:
invade
'infest' is the definition.
(I know that infest can be written as invade)
'new divan with energy' is the wordplay.
'new' indicates an anagram.
'with' means one lot of letters go next to another.
'energy' becomes 'e' (physics symbol as in E=mc2).
'divan' is an anagram of 'invad'.
'invad'+'e'='INVADE'
(Other definitions for invade that I've seen before include "Violate" , "Encroach upon" , "Enter other's territory aggressively" , "Enter with armed forces to attack" , "make unwelcome advances" .)