How Much Does a 20-watt phone charger Cost to Run in Washington?
A 20-watt phone charger uses 0.02 kWh per hour and costs $0.002 per hour at $0.115/kWh in Washington. Used 2 hours a day, that is $0.005 per day, $0.138 per month and $1.68 per year.
Calculate your own cost
- Per hour
- $0.0020.02 kWh
- Per day
- $0.0050.04 kWh
- Per week
- $0.0320.28 kWh
- Per month (30 days)
- $0.1381.2 kWh
- Per year
- $1.6814.6 kWh
Formula: watts ÷ 1,000 × hours × rate. Edit any box and every number updates instantly.
People also ask
How much does a 20-watt phone charger cost per hour?
At $0.115/kWh, it costs $0.002 per hour. The maths: 20 W ÷ 1,000 = 0.02 kWh per hour, × $0.115 = $0.002.
How much does it cost per month?
Used 2 hours a day for 30 days, it costs about $0.138 per month and uses 1.2 kWh. Change the hours in the calculator above to match how you use it.
How many kWh does it use?
0.04 kWh per day, 1.2 kWh per month and 14.6 kWh per year at 2 hours a day. A kWh is one kilowatt (1,000 W) used for one hour. It is the unit on your electricity bill.
How can I lower the cost?
Estimate using charging time and average draw rather than the charger’s maximum label alone. Check your bill for the exact rate and enter it above.
Does my electricity rate change the answer?
Yes, a lot. At 10¢ per kWh the monthly cost is $0.12 and at 30¢ it is $0.36. Find your rate on your bill (total cost ÷ kWh used) and type it into the calculator.
Cost by hours of use in Washington
| Used per day | Energy per day | Cost per day | Cost per month | Cost per year |
|---|---|---|---|---|
| 1 hour | 0.02 kWh | $0.002 | $0.069 | $0.84 |
| 2 hours | 0.04 kWh | $0.005 | $0.138 | $1.68 |
| 3 hours | 0.06 kWh | $0.007 | $0.207 | $2.52 |
| 4 hours | 0.08 kWh | $0.009 | $0.276 | $3.36 |
| 5 hours | 0.1 kWh | $0.012 | $0.345 | $4.20 |
| 6 hours | 0.12 kWh | $0.014 | $0.414 | $5.04 |
| 7 hours | 0.14 kWh | $0.016 | $0.483 | $5.88 |
| 8 hours | 0.16 kWh | $0.018 | $0.552 | $6.72 |
| 9 hours | 0.18 kWh | $0.021 | $0.621 | $7.56 |
| 10 hours | 0.2 kWh | $0.023 | $0.69 | $8.40 |
| 11 hours | 0.22 kWh | $0.025 | $0.759 | $9.23 |
| 12 hours | 0.24 kWh | $0.028 | $0.828 | $10.07 |
| 13 hours | 0.26 kWh | $0.03 | $0.897 | $10.91 |
| 14 hours | 0.28 kWh | $0.032 | $0.966 | $11.75 |
| 15 hours | 0.3 kWh | $0.035 | $1.04 | $12.59 |
| 16 hours | 0.32 kWh | $0.037 | $1.10 | $13.43 |
| 17 hours | 0.34 kWh | $0.039 | $1.17 | $14.27 |
| 18 hours | 0.36 kWh | $0.041 | $1.24 | $15.11 |
| 19 hours | 0.38 kWh | $0.044 | $1.31 | $15.95 |
| 20 hours | 0.4 kWh | $0.046 | $1.38 | $16.79 |
| 21 hours | 0.42 kWh | $0.048 | $1.45 | $17.63 |
| 22 hours | 0.44 kWh | $0.051 | $1.52 | $18.47 |
| 23 hours | 0.46 kWh | $0.053 | $1.59 | $19.31 |
| 24 hours | 0.48 kWh | $0.055 | $1.66 | $20.15 |
How we worked it out
- Energy per hour: 20 W ÷ 1,000 = 0.02 kWh
- Cost per hour: 0.02 kWh × $0.115 = $0.002
- Cost per day: × 2 hours = $0.005
- Month and year: × 30 days = $0.138, × 365 days = $1.68
Washington electricity prices
Washington pays about $0.115 per kWh, which is 34% lower than the US average of $0.175. The same phone charger would cost $0.21 a month at the national average.
What it costs in different places
Same 20-watt phone charger, 2 hours a day. Only the local electricity rate changes.
| Place | Rate per kWh | Cost per month |
|---|---|---|
| United States | $0.175 | $0.21 |
| California | $0.32 | $0.384 |
| Texas | $0.155 | $0.186 |
| New York | $0.25 | $0.30 |
| Florida | $0.155 | $0.186 |
| Illinois | $0.17 | $0.204 |
| Pennsylvania | $0.18 | $0.216 |
| Ohio | $0.17 | $0.204 |
| Washington | $0.115 | $0.138 |
About phone charger running costs
Phone chargers draw power mainly while charging, with a very small standby draw for many modern models. The adapter’s maximum rating is not constant consumption.
Typical sizes: 5 W, 10 W, 20 W, 30 W.
How to spend less: Estimate using charging time and average draw rather than the charger’s maximum label alone.
What this estimate assumes
- The appliance draws its full stated wattage the whole time it is on. Real units with a thermostat cycle off and cost less.
- Wattage is the typical label value, not a measured value. Check the label on your own appliance.
- The rate is an approximate residential average in Washington. Your bill may include fixed fees, tiers or time-of-use pricing. Edit the rate above.
- A month is 30 days and a year is 365 days.