At this old thread: https://www.physicsforums.com/showthread.php?t=362716 the reply: Now, whether this extra current matters depends on why the power supply voltage is dropping. If it is due to excessive current, then yes, increased current in one house could cause a slight drop in voltage for the other houses. Has me curious as to whether this can be a real scenario. Is it possible that if a neighbor uses a greater deal of power than your normal neighbor, that your voltage could drop? How can that affect your service? Lets say your whole home voltage level drops to 112 volts. Now all currents rise, correct? And this could possibly cause breakers to trip that normally wouldn't have tripped with the correct/higher voltage? Just curious as to what the concerns would be if a neighbor decided to open shop at his home and begins to utilize more power.