Bulb working with electricity generator (5)
I believe the answer is:
onion
'bulb' is the definition.
(plant bulb)
'working with electricity generator' is the wordplay.
'working' becomes 'on' (on can mean working or activated).
'with' says to put letters next to each other.
'electricity generator' becomes 'ion' (I can't justify this - if you can you should give a lot more credence to this answer).
'on'+'ion'='ONION'
Can you help me to learn more?
(Other definitions for onion that I've seen before include "Alliaceous plant" , "veggie" , "Shape of Russian dome" , "Hot dog topping" , "Tear-jerking bulb" .)