He has loads of energy (7)
I believe the answer is:
coalman
'he has loads of energy' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'he has loads of' is the wordplay.
I cannot quite understand how this works, but
'he' could be 'man' (I've seen this in another clue) and 'man' is found in the answer.
'loads' could be 'c' and 'c' is found within the answer.
'of' could be 'o' and 'o' is found in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Another definition for coalman that I've seen is " who was sacked making delivery".)