Parody of commercial supporting cleaner energy (7)
I believe the answer is:
charade
'parody' is the definition.
(synonyms)
'commercial supporting cleaner energy' is the wordplay.
'commercial' becomes 'ad' (abbreviation for advertisement).
'supporting' says to put letters next to each other (in a down clue, some letters go below others).
'cleaner' becomes 'char' (charwoman is a type of cleaner).
'energy' becomes 'e' (physics symbol as in E=mc2).
'ad' put after 'char' is 'charad'.
'charad'+'e'='CHARADE'
'of' is the link.
(Other definitions for charade that I've seen before include "Film with Cary Grant and Audrey Hepburn" , "Ludicrous pretence" , "Ridiculous pretence" , "absurd act" , "Game in which the answer is acted out" .)