# Run out of electrons

If electricity is a flow of electrons in a wire then eventually all electrons will leave the beginning of the wire and reach the end of the wire. Is that possible? Why if not? What will happen then if yes?

• But more electrons are added back to the beginning of the wire by virtue of a closed circuit (oversimplification, but...) – Tom Carpenter Nov 15 '16 at 21:04
• Electrons are also constantly generated (and recombining) due to thermal generation and carrier injection. – jbord39 Nov 15 '16 at 21:55
• Beware of the "empty-pipes fallacy." Wires are not like empty pipes with electrons injected into one end. Wires are like pre-filled pipes, always containing tens of thousands of coulombs of mobile electrons. – wbeaty Nov 16 '16 at 6:41

If 1A of current is travelling through a wire, then 1 coulomb or approximately $6.241\cdot10^{18}$ electrons are passing a given point in the wire per second. If you have a power source such as a battery, eventually an equilibrium is reached as the battery discharges, and there is 0V of potential difference across the wire. At this point there are still electrons on both sides of the wire, but since there is no potential difference, there will be no current flow, so the electrons stay there.