Burning questions

How many watts does a phone charger use: Little vampires

The average American spends about 3.5 hours a day on their smartphone. Have you ever wondered how much electricity your smartphone consumes? And how many watts does a phone charger use, especially when you leave it plugged in 24/7? We’ll break it all down for you.

Your smartphone consumption and how to guesstimate it

To find the power your phone needs to charge from zero to full, we need to know the capacity and voltage of your phone’s battery. These can be either found on the battery itself or in your phone’s specification or figured out by installing a special app. On average, phones have a battery capacity of about 5000mAh and a voltage of about 3.8V. To estimate the consumption needed for a full charge, we multiply milliampere-hours by volts and divide by 1000.

Watt-hours = Milliampere-hours × Volts

Charger’s efficiency ranges from 50% to over 90%

The average phone might require somewhere about 19 watt-hours for a full charge. But that isn’t the power the charger actually draws. The difference between the power taken from the outlet and the power flowing to your phone is in the charger’s efficiency. The efficiency of chargers can range from 50% to over 90%. In other words, for every watt given to the device, the charger draws between 1.1 and 2 watts from the outlet.

Let’s say you fully charge your phone every day and your charger’s efficiency is about 80%. That makes 23Wh per day, 690Wh per month, and 8.5kWh per year, assuming you always plug the charger out when your phone is charged. Do you, by the way?

Energy vampires and how to find them

A plugged-in charger drains up to 0.5 watts even when not charging your phone

The energy vampires are electronic devices that continue to consume electricity even when they’re seemingly turned off but still connected to the mains. They lurk in standby mode, while their tiny lights and internal processes silently suck power from the grid.

Your phone charger is one of them. Left plugged in, it consumes up to 0.5 of a watt. Per year, that makes about 4.5kW. Depending on the price per kWh in your state, it may cost you somewhere between ¢45 and $1.5 per year. It doesn’t sound like much but add a laptop, TV, coffee maker, game console, bedside lamp, and you’re running $100 to $200 a year for devices you don’t even use.

How do we deal with energy vampires? Here are the tips from experienced vampire hunters:

  • Unplug unused electronics: This is the simplest and most effective way to eliminate vampire loads. When you’re not actively using electronics, simply pull the plug.

  • Use power strips: Plug electronics into power strips with on/off switches. This allows you to easily cut power to the entire group of devices with a single switch.

  • Look for energy-efficient models: When replacing appliances, opt for energy-efficient models that use less power even in standby mode.

Solar power and how to charge your phone on the go

What happens when you’re on the go and your phone’s battery starts to dwindle? A power bank can only take you so far. The solution for all the energy needs of a camper is solar power.

Portable solar panels can come in a wide variety of sizes and capacities. A 30-watt folding panel can easily fit in your pocket. You can hang it on your backpack to charge your phone on the go. Even such a small panel can charge your phone from dead to full in about two hours. With the more serious 200 and even 300-watt folding panels, you can charge not only your phone but also your laptop, GPS or even a mini-fridge.

A natural addition to solar panels is a power station. Together, they form a PV generator. Power station combines in itself an inverter, a charge controller and a small power bank — perfect for keeping you powered anywhere you go. Learn more in our article “Finding solar panels for a PV generator: Tips and tools”.

Start saving money with solar panels!

Check what solar panels we have in stock or get a quote for a system from our engineer.

Shop solar panels

Years of experience in translation and a love of nature help Julia find the right words to encourage going solar. She joined the team in 2023 and is happy to make her contribution to a greener future.

More articles from this author

Read Also

How much electricity does your house use? Breaking down electric bill

A1 Solar Scholarship 23/24 report: Results and best parts

How much energy does a heat pump use? Pumping down the costs

DIY home energy audit: HERS Index Score, Audit Checklist

How many watts does a treadmill use? Running costs

Stay tuned

Learn about the latest arrivals and discounts first!

By clicking "Subscribe", I agree by electronic signature to: (1) receive marketing and other texts and messages from A1SolarStore, directly or from third parties acting on its behalf, at the email address I entered above; (2) the Terms and Conditions; and (3) the Privacy Policy.