Wasted energy involves everyone as a rule (9)
I believe the answer is:
generally
'as a rule' is the definition.
(I've seen this before)
'wasted energy involves everyone' is the wordplay.
'wasted' indicates anagramming the letters.
'involves' indicates putting letters inside.
'everyone' becomes 'all' (all people).
'energy' is an anagram of 'genery'.
'genery' placed around 'all' is 'GENERALLY'.
(Other definitions for generally that I've seen before include "most of the time" , "as usual" , "Usually, as a rule" , "For the most part" , "In most cases, as a general rule" .)