How is energy wasted from chargers left plugged in?

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kidstixies

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I have heard that leaving a charger (ie. cell phone, laptop) in the outlet while nothing is plugged in wastes energy. I believe this. However, i have two questions.
1. Where does the energy go?
2. Is it the same amount as it would use for charging the device?
 
Most Chargers are actually transformers also known as wall warts. They take the 110 volt alternating current and transform it into lower voltage say 6, 12, maybe 24 volts DC, or at least a close enough proximity to DC. This transformation though is not really very efficient. For every 10 watts of electricity coming into the wall charger less than 10 watts of electricity come out. The rest of the energy ends up as heat, which is why the chargers get warm to the touch. I don't know what the losses are but it is significant. So even after your phone or whatever is all charged up and not sucking up any more juice, the charger is still transforming electricity in a inefficient manner and wasting electricity.
 
No it wouldn't use the same amount of power if its just plugged into the wall. Think about your Tv it uses some power when its off. More when its on. I believe the hydro company calls this phantom loads more info can be found with the link I provided.
 
you over charge something and is released into the machine and when that fills up you still use the energy just it disbursed to whatever is closest as whatever plug into it doesn't just vanish if you thinking of that.
 
1. There is energy stored in magnetic fields you can't see, as well as small amounts of energy given off as heat.
2. It is much, much less than charging the device.

Also, the more sophisticated the charger the more energy it uses. I believe laptop chargers have some active monitoring circuitry in them which uses energy. Cell phone chargers are all passive components that don't actively use energy, a small amount leaks out as I mentioned.
 
great question, it may use a lesser amount of energy, but the electrons from the electrical outlet still makes an electromagnet which as a result, continues to sprial around for energy. if you plug out a charger or shut off a power bar, it will stop those electrons from running into the outlet.
 
All transformers, and a charger has one of those, have a continuous wire that connects the two input lines from the utility.
Whenever you complete a circuit you allow current to flow through that circuit, and allowing current to flow is what we call using electric power.

When we are actually charging a battery, we allow even more current to flow. Why? because we reduce the magnetic inductance in the transformer. That means we reduce the effective resistance to flow of electrons, so more flow. As the battery approaches full charge, the amount of current allowed through the transformer declines so that at full charge, we are drawing almost the same charge as when the battery is not there, But it is never quite as low a current. The battery itself will leak some power and stay warm.

Where does energy go when we just let it flow through the circuit? Well, the electrons go back to the power station where they cause the generator to work harder to maintain rotational speed. In effect the energy is lost back at the generator.
 
a charger is a simple transformer made of coils of wire.
that coil of wire is of high enough resistance to be a load and not a short. the electricity flows across the coil from one hole of the wall outlet to the other. the coils of wire are resistive to the flow and that causes heat and an electromagnetic feild to be disapated by the coil.it is a convertion of electricity into heat and electro motive force or EMF. the coil does this continuosly as long as it is pluged in.
 
It will make no noticeable difference if you leave it plugged in or not. Depending on the charger, they will use a fraction of a watt to nothing noticeable at all. So you would likely not notice in you entire lifetime a difference of leaving them plugged in or not.
 
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