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I know current flows in a loop and energy is used to move it in a loop. Now suppose we get a single phase AC (220/120V) electricity supply for our home and we have earth connection to prevent shocks from the current that leaks on to the metal body of our appliances.

So we have a circuit loop in which current (electron present in the wire) flows from station to house and back to the station (the direction of electron is opposite to that of conventional current flow). Also there are fixed number of free electrons present in this circuit loop.

Now consider a situation where somehow current leaks to the body of a appliance and goes to ground instead of returning back to the power station( due to earthing).

How is this lost current compensated by the power station which never receives it back ?

I was talking about conventional current so if you talk about electrons I can reframe the question as how does the power station deal with the extra electrons that flows from ground(earth) back to the loop?

Note: I know in the real scenario there are three-phase wires from the power station and a local step down transformer steps it down and provides us with 1 or 2 phases which forms a micro loop between the transformer and the house so the situation remains the same (wouldn't it?), although contained to the move loop instead of the giant loop.

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  • \$\begingroup\$ Lost in the measurement errors - how many millions of amps are produced by the power stations? \$\endgroup\$ – Solar Mike Aug 18 '18 at 14:13
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I know current flows in a loop and energy is used to move it in a loop. Now suppose we get a single phase AC (220/120V) electricity supply for our home and we have earth connection to prevent shocks from the current that leaks on to the metal body of our appliances.

OK so far.

So we have a circuit loop in which current (electron present in the wire) flows from station to house and back to the station (the direction of electron is opposite to that of conventional current flow). Also there are fixed number of free electrons present in this circuit loop.

Stop thinking about electrons. It doesn't help. Just think of voltage, current and energy flow.

Now consider a situation where somehow current leaks to the body of a appliance and goes to ground instead of returning back to the power station( due to earthing). How is this lost current compensated by the power station which never receives it back ?

The neutral conductor is "neutralised" by connecting it to ground. If there is no ground reference then there is no reason for the current to flow to ground.

I was talking about conventional current so if you talk about electrons I can reframe the question as how does the power station deal with the extra electrons that flows from ground(earth) back to the loop?

Again, thinking in terms of electrons is no help. Current returns to the power station through the ground and back to the source - the generator or its transformer in this case.

Further reading:

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  • \$\begingroup\$ There are no extra electrons. Current out = current return. \$\endgroup\$ – Transistor Aug 18 '18 at 14:21
  • \$\begingroup\$ But how is the current returning back to the loop (which goes to ground) ? \$\endgroup\$ – paulplusx Aug 18 '18 at 14:22
  • \$\begingroup\$ Through the earth return. Did you read the "further reading" links? \$\endgroup\$ – Transistor Aug 18 '18 at 14:24
  • \$\begingroup\$ Sorry for the confusion I saw the reference you used. The diagram clears my confusion. Thank you so much. \$\endgroup\$ – paulplusx Aug 18 '18 at 14:27
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    \$\begingroup\$ Yes, that's the whole idea. \$\endgroup\$ – Transistor Aug 19 '18 at 8:30

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