Energy in fire might not be dispersed temporarily (3,3,4,5)
I believe the answer is:
for the time being
'temporarily' is the definition.
(I've seen this in another clue)
'energy in fire might not be dispersed' is the wordplay.
'energy' becomes 'e' (physics symbol as in E=mc2).
'in' is an insertion indicator.
'dispersed' is an anagram indicator.
'fire'+'might'+'not'+'be'='firemightnotbe'
'firemightnotbe' anagrammed gives 'forthetimbeing'.
'e' going inside 'forthetimbeing' is 'FOR THE TIME BEING'.
(Another definition for for the time being that I've seen is " at the moment".)