To get the icon to show up, I believe you have to use an entity.
I think you can:
Make an entity with the should_be_remembered_as_power_up ="true" and auto_pickup="true". (See Perks for examples)
Add a system to the hull that uses spawn_entity to spawn the entity, destruct the system after use.
It is a kludge, but it gets what you want.
Contrishooter doesn't use energy, it uses credits. So the display is caught between energy & credits.