Is it more energy efficient to charge a phone/tablet using a desktop/laptop while your computer is being used vs using the charger?
Is it more energy efficient to charge a phone/tablet using a desktop/laptop while your computer is being used vs using the charger?
I was just thinking if you are on your computer anyway would it just use some of the excess electricity that your computer would have wasted or would it be worse than charging your phone from a charger while using your laptop separately.
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I'd like to remind everyone of the "vampire effect" of wall-wart chargers - if you just leave them plugged into the wall waiting for you to connect a device, you're constantly wasting a bit of electricity. That should also be involved in the efficiency decision of using the already plugged in computer or laptop.
Someone correct me, but unless your charger is warm to the touch, this is a very insignificant amount of power a year.
Your TV pretending to be off probably draws more every couple of days.
Anything with a remote, anything with a screen, way too many “computerized” appliances. Leaving a computer on
If you care to minimize Standby power "comfortably", usually libraries or power companies will let you borrow an AC Power Meter free of charge.
You can use that to inspect your various devices Standby Power. For example I have an amplifier that pulls nearly 15W in standby, since finding out it lives on a smart plug.
However my TV pulls less than 1W, and at that point I prefer the convenience of just being able to use the remote to turn it on.
(Also keep in mind with the smart plug solution that the plug itself will pull a little bit of power too, this will pretty much always be <1W though.)
Vampire effect was a real problem with older transformer-based wall warts. If you still have one that feels heavy and solid, or has a fixed energy rating on the label, this is you
If it feels light, almost empty, or the label has a wide range of frequencies and voltages, it uses an order of magnitude less and really doesn’t add up anymore. I believe it’s something like a couple cents per year.
Edit: found something from 14 years ago calculating the worst case scenario of leaving a wall wart plugged in as 7¢/month but I don’t believe it’s anywhere near that expensive for a modern one …. Although it’s probably more telling that I didn’t find anything more recent with a price estimate.
Unless your chargers are generating a noticeable amount of heat (and they shouldn't be), the amount of electricity they are using is simply negligible. Electricity cannot simply evaporate into thin air.