phone charger

How many watts does a phone charger use?

While not as power-hungry as appliances like air conditioners or washing machines, it’s important to know how much electricity a phone charger uses when you’re looking at your whole home’s energy usage.


Key takeaways about powering a phone charger


  • On average, phone chargers use about 5 watts of electricity.
  • Charging a phone once a day will use about 0.15 kilowatt-hours of electricity per month and 1.83 kilowatt-hours of electricity per year.
  • Phone chargers are very cheap to run: it costs about 2 cents to use one for a month and 26 cents to use one for a year.
  • The best way to save money on electricity is to install solar panels. Start comparing your options on the EnergySage Marketplace today.

In this article

How much electricity does a phone charger use?

Generally, phone chargers use about 5 watts (W) of electricity. Some faster chargers can use up to 20 W, but the majority of standard chargers are more around the 5 W range. Phone chargers usually use one to two amps, and connect to a 120-volt outlet .

How many times you charge your phone has a large impact on how much electricity your phone charger uses. Assuming one full charge takes one hour:

  • Charging your phone once per day uses 0.035 kilowatt-hours (kWh) of electricity per week, 0.15 kWh per month, and about 1.83 kWh per year.
  • Charging your phone twice per day uses 0.07 kWh of electricity per week, 0.3 kWh per month, and about 3.65 kWh per year.

While 5 W is a good estimate for the average phone charger wattage, there are also “fast” chargers available for many phone models that pull higher wattages. Here’s how much electricity you’ll use over the course of a year for different wattage phone chargers:

How many watts do different phone chargers use in a year?

Phone charger wattageHours per year runYearly kWh of electricity
5 W365 hours1.83 kWh
10 W365 hours3.65 kWh
15 W365 hours5.48 kWh
20 W365 hours7.30 kWh

We’ll mostly be referring to the electricity used by phone chargers in terms of kWh in this article. The reason is simple: your electric bill is measured in kWh, and you get charged based on the kWh of electricity you use per month!

Watts, amps, voltage, and more: what do they mean?


There are a lot of terms you can use to describe how electricity flows and is used by appliances. We’ve already mentioned most of them – here are a few definitions to keep things straight:

  • Volts (V): volts (short for voltage) are measures of electrical pressure differences. Put simply, voltage is the speed of electricity passing through a circuit.
  • Amps (A): amps (short for amperes) are a measure of electrical current. Put simply, amps are the amount of electrons (which make up electricity) flowing through a circuit.
  • Watts (W) and kilowatts (kW): multiplying volts x amps gets you watts (or wattage). Put simply, watts are the rate of electricity consumption. A kilowatt is just 1,000 watts.
  • Kilowatt-hours (kWh): lastly, kilowatt-hours are how your electric bill measures your energy usage. Simply put, kilowatt-hours are electricity consumption over time.

You can think of these terms like water flowing through a pipe. Voltage is the water pressure, amps are the amount of water flowing past any point, and wattage is the overall rate of water flow through the pipe.

How much does it cost to power a phone charger?

When you get your monthly electric bill, you only see the total amount you’re charged, not how much each appliance contributes to your final bill. Based on a typical wattage of 5 W for phone chargers (amounting to about 1.83 kWh/year if you use your phone charger for one full charge per day) and using state average electricity rates, here’s how the cost to run a phone charger pans out over the course of a month and a year:

Monthly and yearly costs to run a phone charger by state

StateAverage electricity rateCost per monthCost per year
California22.00 ¢ / kWh$0.03$0.40
New York20.59 ¢ / kWh$0.03$0.38
Texas12.56 ¢ / kWh$0.02$0.23
Massachusetts22.59 ¢ / kWh$0.04$0.41
Florida12.21 ¢ / kWh$0.02$0.22
Virginia12.58 ¢ / kWh$0.02$0.23
New Jersey16.20 ¢ / kWh$0.03$0.30
Maryland14.48 ¢ / kWh$0.02$0.26
Washington10.38 ¢ / kWh$0.02$0.19
US Average14.19 ¢ / kWh$0.02$0.26

Note: average electricity rates are based on October 2021 data from the U.S. Energy Information Administration (EIA).

Looking to offset your electric bills (and the energy these appliances use) with solar? When you sign up (for free!) on the EnergySage Marketplace, you can compare solar quotes from high-quality, local solar installers. Make sure to keep in mind your current and future electricity usage, and talk about how that could change with your installer for the most accurate quotes.

Frequently asked questions about powering a phone charger

What’s the best time to run a phone charger?

If you’re on a time-of-use (TOU) rate plan, you are charged different amounts for electricity throughout the day. In general, it’s cheaper to use appliances during “off-peak” hours, which are usually overnight.

What size battery do you need to back up a phone charger?

All popular home batteries can power a phone charger: most lithium-ion batteries like the Tesla Powerwall or Generac PWRcell have a power rating of 4 to 5 kW or higher and 10+ kWh of usable capacity. phone chargers use about 5 W (0.005 kW) of power at any one time, meaning a battery will be plenty suitable for backing up and powering your phone charger.

How many solar panels does it take to run a phone charger?

On average phone chargers use about 5 W of electricity to stay powered. With solar panels rated at around 350 W, you’ll be able to power a phone charger easily with one standard solar panel.

What are ENERGY STAR appliances?

ENERGY STAR is a U.S. government-backed system that certifies how energy efficient appliances are. If an appliance is better than the average appliance in its category by a certain amount, it is labeled as “ENERGY STAR certified.” ENERGY STAR appliances cost less money to run, given that they are more efficient with the electricity they use.

How much money can solar panels save you?

Solar savings vary widely, and your unique savings depend on factors like electricity usage, location, and electric rates and plans. In general, most homeowners can expect to save somewhere between $10,000 and $30,000 over the lifetime of a solar panel system. On average, it takes between 7 and 8 years for most homeowners who shop for solar on EnergySage to get their solar panels to pay for themselves.

Going solar is one of the most effective ways to reduce or eliminate your electric bill, and you should make sure you are getting several quotes from reputable installers before you decide to move forward. Visit the EnergySage Marketplace to get solar quotes from installers in your area and begin comparing options.


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About Jacob Marsh

Jacob is a researcher and content writer at EnergySage, where he's an expert on current issues–and new technology!–in the solar industry. With a background in environmental and geological science, Jacob brings an analytical perspective and passion for conservation to help solar shoppers make the right energy choices for their wallet and the environment. Outside of EnergySage, you can find him playing Ultimate Frisbee or learning a new, obscure board game.

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