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Where does surplus current go if i switch off appliance

  1. Mar 28, 2014 #1
    Hello everyone,

    I've read about green day when government says to switch off appliances for an hour in evening.

    But if everyone switches off appliance, then where will all that current go? We cannot stop generator so quickly.

    It's like a dam is giving water to three pipes, in full force. Suddenly two pipes are removed, so wouldn't that one pipe carry all the water and if that one pipe doesnt carry water, wouldn't dam explode since there's more water than it can contain?

    Who tells the generator, to supply less current?

    Also if I have a single load which with a power supply. Load would be resistor(i hope i'm right.) so if i increase resistance in series(which is like adding load) then the total resistance increases, so current should reduce.

    I asked professors but they just said that green day works as news papers say so.
  2. jcsd
  3. Mar 28, 2014 #2

    Simon Bridge

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    The wave reflects off the end of the open circuit. It registers as a decreased demand at the main control.
    Note: nothing like water in pipes - if there is nowhere to go, the current does not go anywhere.

    There is usually some sort of control station somewhere - maybe owned by the power company - which coordinates the different power stations. In each station there is a control board to regulate which generators are going and how fast they go - like the throttle in a car. It amounts to some people watching a dial and turning a knob - if the dial gets higher, they turn the know up and if it gets low they turn the knob down.

    There is a nice demonstration on video somewhere showing a bicycle powered house.

    The principle is the same.

    You are interested that big loads should draw more power, but a bigger load at the same voltage draws less current ... suggesting less power is drawn?

    Note: in the video, when the shower turns on, adding load to the system, the voltage supplied drops.
    The cyclists have to pedal harder to keep the voltage high enough to power the shower.

    You pay for power, not current.

    The green day reduces power consumption.
    Last edited by a moderator: Sep 25, 2014
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