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How Much Power Does It Take to Charge a Phone? Energy Consumption Explained

iphone charging

A conventional smartphone will consume around 2 to 6 watts of electricity to get to a full charge. But when you leave your charger plugged into an outlet, it will consume close to 0.5 watts. These numbers have taken into consideration a couple of factors, such as the time taken to fully charge the phone’s battery and the charger wattage.

The good thing is that charging a traditional phone isn’t as costly as other household appliances, in the long haul. Even if you get to charge it every day for at least 3 hours, you’ll never be able to rack up more than $10 per year.

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How Much Do You Save By Unplugging a Fully Charged Phone?

Well, according to the energy department, you only get to save about 44 cents every year. Let’s say you’re working with an iPhone 11, which has been designed to use a 3110 mAh battery.

This model usually comes with a charger that delivers a maximum power output of 5 watts. What’s more, it only takes 3 hours to up the battery juice from 0 to 100%. Meaning, even if you wanted to, there’s no way you’ll be able to consume more than 15 watts, just charging a single device. And the last time we checked, the cost of 15 watts is less than the price of a cup of latte.

Then again, it’s evident that the smartphone industry is constantly evolving. It’s not impossible to find a phone that uses more than 40 watts of power, given some of them have huge screens and faster processors. If you’re not so sure how much power your phone consumes per charge, go get an electricity usage monitor. It’s a device designed to count power consumption by kilowatts-hours.

iphone and charger
Image Credit: mhoppsy, Pixabay

What’s The Annual Cost of Powering a Phone?

We all hate bills, but what we hate even more about electrical bills is the fact that they don’t usually give us the specifics. Or wouldn’t you want to know how much each household appliance is contributing to your monthly expenses?

Nonetheless, we took it upon ourselves to find out what the average costs of powering up a typical phone charger were, in different states.

Just a quick reminder though, these calculations are based on 5-wattage power consumption, which equates to 1.83 kWh per year—in the case of someone who charges their phone daily. Also, you should note that the average electricity rates keep fluctuating from time to time, as it’s influenced by several economic forces. Therefore, these are only estimates, using data obtained from the US Energy Information Administration (EIA).

Costs Of Powering a Phone by State (Cents Per Kilowatt)

State Average Electricity Rate Phone Charging Average Cost Per Month Phone Charging Average Cost Per Year
Washington $10.42 $0.02 $0.19
New Jersey $17.21 $0.03 $0.30
New York $21.88 $0.03 $0.38
California $26.77 $0.03 $0.40
Florida $13.95 $0.02 $0.22

Is Charging Your Phone Overnight a Bad Idea?

It’s no secret that most of us find it convenient to charge our phones while we’re sleeping. It’s not just because we won’t be using it, but because the outlet is usually conveniently located next to our beds. Unfortunately for you, the answer you’re looking for is not a simple “yes” or “no.”

You see, this current generation of smartphones only requires 2 to 3 hours of charging time. And that could only mean that it will have to stay at full charge for several hours, and that doesn’t augur well with the battery. Most of us probably didn’t know this, but phones don’t usually stay at 100% indefinitely, once they get to full charge. They tend to drain a little, to 99%, then juice up once more.

And this process will be repeated all through the night until you unplug it from the outlet. You can right away tell how tiresome that is, right? And the effects will be felt by the battery, as it’s the component that’s being heated up constantly, before being worn down.

The situation is even worse if the type of charger that you’re using is the faster charger. You could get away with it once or twice, but if it’s becoming a habit, you’ll soon start to notice the difference in the battery life. Needless to say, its performance will have degraded.

If you’ve noticed that your phone is running out of juice, but you have to leave the house very early in the morning, plug it in while you’re having your evening meal, and then unplug it once you get to bed. It’s okay to do so, even if it’s not fully charged. Plug it in one more time when you wake up, as you prepare to leave for work.

smartphone charging
Image Credit: StockSnap, Pixabay

Voltage, Amperes, & Watts: What Do They Represent?

Every electrical circuit needs a power source. And the primary role of the source is to push current through a conducting loop. “Pushing” means that there’s pressure involved. Pressure that’s measured in volts (V). Back in the day, we used to refer to voltage as the electromotive force. That’s why you’ll find it is represented by an “E” in several equations, such as that which explains Ohm’s Law.

If you’d like to determine the amount of current flowing through an electrical circuit, you’ll need to work in amperes. This unit of measure represents the rate of electron flow in any one given circuit, as it represents the coulombs of electric charge moving past different points of a conducting loop, in a given period.

Watt is the measure of power. Denoted by (W), it answers the question, “How much work is being done, or at what rate is energy being consumed, when a single ampere of current flows through a circuit?” You easily can determine your wattage by multiplying volts by amps. And when you divide that answer by 1000, you get kilowatt (kWh).

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Final Words

Smartphones don’t usually consume too much power. So, if you’ve noticed your electricity bill has skyrocketed over the past couple of months, it has to be due to a different appliance. Have you checked the heaters and the cooling appliances? Because from our experience, those usually consume the most energy.

Featured Image Credit: nhothu82st0, Pixabay


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