Electrons carry a negative electrical charge. In S.I. units, the electron's charge is#1.2 x#Coulomb to four significant figures.
Protons are positively charged, electrons are negatively charged, and neutrons have no charge. The charge of one electron and one proton are equal yet opposite so
you're asking a perfectly legit question and
you've already guessed that without an led or another obvious power draw it's doubtful that it uses any electricity.
parasitic loads are real but a piece of equipment that doesn't have them DOES NOT USE any power at all until the circuit is completed (turned on)
Voltage is described as "electrical potential"
"Potential" means that a thing can happen but absent the proper conditions, it will not.
there is no current flow in a circuit or a wire until the circuit is completed, a hot wire cannot hurt you if you touch it and you are not grounded. PLEASE DO NOT TEST THIS YOURSELF, a professional demonstate it to you.
The current is not there but the potential is, electricity travels at the speed of light through a conductor, it may seem that a lightbulb goes on instantly when you flip a switch, but (a very short) time elapses between the switch making contact and the filament beginning to light up.
Until you give it some place to go..........electricity is not there at all.