Cost to Run a 900-watt air conditioner for 10 hours in Washington
Running a 900-watt air conditioner for 10 hours uses 9 kWh and costs $1.04 at $0.115/kWh in Washington. Do that every day and it adds up to $31.05 a month.
Calculate your own cost
- Per hour
- $0.1040.9 kWh
- Per day
- $1.049 kWh
- Per week
- $7.2563 kWh
- Per month (30 days)
- $31.05270 kWh
- Per year
- $377.783,285 kWh
Formula: watts ÷ 1,000 × hours × rate. Edit any box and every number updates instantly.
People also ask
How much does a 900-watt air conditioner cost per hour?
At $0.115/kWh, it costs $0.104 per hour. The maths: 900 W ÷ 1,000 = 0.9 kWh per hour, × $0.115 = $0.104.
How much does it cost per month?
Used 10 hours a day for 30 days, it costs about $31.05 per month and uses 270 kWh. Change the hours in the calculator above to match how you use it.
How many kWh does it use?
9 kWh per day, 270 kWh per month and 3,285 kWh per year at 10 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?
Set the thermostat to 78°F (26°C), clean the filter monthly and shade sunny windows. 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 $27.00 and at 30¢ it is $81.00. 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 | 0.9 kWh | $0.104 | $3.11 | $37.78 |
| 2 hours | 1.8 kWh | $0.207 | $6.21 | $75.56 |
| 3 hours | 2.7 kWh | $0.311 | $9.32 | $113.33 |
| 4 hours | 3.6 kWh | $0.414 | $12.42 | $151.11 |
| 5 hours | 4.5 kWh | $0.518 | $15.53 | $188.89 |
| 6 hours | 5.4 kWh | $0.621 | $18.63 | $226.67 |
| 7 hours | 6.3 kWh | $0.725 | $21.74 | $264.44 |
| 8 hours | 7.2 kWh | $0.828 | $24.84 | $302.22 |
| 9 hours | 8.1 kWh | $0.932 | $27.95 | $340.00 |
| 10 hours | 9 kWh | $1.04 | $31.05 | $377.78 |
| 11 hours | 9.9 kWh | $1.14 | $34.16 | $415.55 |
| 12 hours | 10.8 kWh | $1.24 | $37.26 | $453.33 |
| 13 hours | 11.7 kWh | $1.35 | $40.37 | $491.11 |
| 14 hours | 12.6 kWh | $1.45 | $43.47 | $528.89 |
| 15 hours | 13.5 kWh | $1.55 | $46.58 | $566.66 |
| 16 hours | 14.4 kWh | $1.66 | $49.68 | $604.44 |
| 17 hours | 15.3 kWh | $1.76 | $52.79 | $642.22 |
| 18 hours | 16.2 kWh | $1.86 | $55.89 | $680.00 |
| 19 hours | 17.1 kWh | $1.97 | $59.00 | $717.77 |
| 20 hours | 18 kWh | $2.07 | $62.10 | $755.55 |
| 21 hours | 18.9 kWh | $2.17 | $65.21 | $793.33 |
| 22 hours | 19.8 kWh | $2.28 | $68.31 | $831.11 |
| 23 hours | 20.7 kWh | $2.38 | $71.42 | $868.88 |
| 24 hours | 21.6 kWh | $2.48 | $74.52 | $906.66 |
How we worked it out
- Energy per hour: 900 W ÷ 1,000 = 0.9 kWh
- Cost per hour: 0.9 kWh × $0.115 = $0.104
- Cost per day: × 10 hours = $1.04
- Month and year: × 30 days = $31.05, × 365 days = $377.78
Washington electricity prices
Washington pays about $0.115 per kWh, which is 34% lower than the US average of $0.175. The same air conditioner would cost $47.25 a month at the national average.
What it costs in different places
Same 900-watt air conditioner, 10 hours a day. Only the local electricity rate changes.
| Place | Rate per kWh | Cost per month |
|---|---|---|
| United States | $0.175 | $47.25 |
| California | $0.32 | $86.40 |
| Texas | $0.155 | $41.85 |
| New York | $0.25 | $67.50 |
| Florida | $0.155 | $41.85 |
| Illinois | $0.17 | $45.90 |
| Pennsylvania | $0.18 | $48.60 |
| Ohio | $0.17 | $45.90 |
| Washington | $0.115 | $31.05 |
About air conditioner running costs
Window and split air conditioners use a compressor that cycles on and off. Watts depend on size, from about 500 W for a small unit to 3,500 W for a large one.
Typical sizes: 500 W, 900 W, 1,200 W, 1,500 W, 2,000 W, 3,500 W.
How to spend less: Set the thermostat to 78°F (26°C), clean the filter monthly and shade sunny windows.
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.