Data through April 2026
Running cost · Room Air Conditioners · ENERGY STAR certified
Keystone KSTAW10INV
The Keystone KSTAW10INV is certified at 500 kWh per year (based on 750 standardized hours), roughly $94 at the national average — though seasonal use means your real bill lands in a few months, not twelve. That's close to the middle of the certified pack — about 6% under the median room air conditioner, ranked 158 of 396. Where you live moves the bill from $62 a year in North Dakota to $233 in Hawaii.
Estimated annual running cost · U.S. average rate 18.8¢/kWh
$94/yr
- Per month
- $7.85
- Per day
- 26¢
- Certified use
- 500 kWh/yr
- Cooling capacity
- 10,000 BTU/hr
- CEER
- 15
- Mounting
- Straddles Window
- Variable-speed compressor
- Yes
What it costs in every state
| State | Rate ¢/kWh | This model $/yr | Relative cost |
|---|---|---|---|
| Alabama | 17.4¢ | $87 | |
| Alaska | 27.4¢ | $137 | |
| Arizona | 15.5¢ | $77 | |
| Arkansas | 14.2¢ | $71 | |
| California | 35.3¢ | $176 | |
| Colorado | 16.5¢ | $83 | |
| Connecticut | 32.2¢ | $161 | |
| Delaware | 18.8¢ | $94 | |
| District of Columbia | 25.4¢ | $127 | |
| Florida | 15.4¢ | $77 | |
| Georgia | 15.4¢ | $77 | |
| Hawaiipriciest | 46.6¢ | $233 | |
| Idaho | 12.7¢ | $64 | |
| Illinois | 20.5¢ | $102 | |
| Indiana | 17.9¢ | $90 | |
| Iowa | 13.9¢ | $69 | |
| Kansas | 15.8¢ | $79 | |
| Kentucky | 15.0¢ | $75 | |
| Louisiana | 14.4¢ | $72 | |
| Maine | 28.4¢ | $142 | |
| Maryland | 22.1¢ | $110 | |
| Massachusetts | 29.4¢ | $147 | |
| Michigan | 21.4¢ | $107 | |
| Minnesota | 16.4¢ | $82 | |
| Mississippi | 16.8¢ | $84 | |
| Missouri | 14.0¢ | $70 | |
| Montana | 13.9¢ | $70 | |
| Nebraska | 13.3¢ | $66 | |
| Nevada | 14.3¢ | $71 | |
| New Hampshire | 27.2¢ | $136 | |
| New Jersey | 23.5¢ | $118 | |
| New Mexico | 15.2¢ | $76 | |
| New York | 29.4¢ | $147 | |
| North Carolina | 16.3¢ | $81 | |
| North Dakotacheapest | 12.3¢ | $62 | |
| Ohio | 19.5¢ | $97 | |
| Oklahoma | 13.3¢ | $67 | |
| Oregon | 15.8¢ | $79 | |
| Pennsylvania | 21.5¢ | $107 | |
| Rhode Island | 28.3¢ | $142 | |
| South Carolina | 17.1¢ | $85 | |
| South Dakota | 14.5¢ | $73 | |
| Tennessee | 14.9¢ | $75 | |
| Texas | 17.0¢ | $85 | |
| Utah | 13.3¢ | $66 | |
| Vermont | 24.6¢ | $123 | |
| Virginia | 17.4¢ | $87 | |
| Washington | 14.4¢ | $72 | |
| West Virginia | 16.1¢ | $80 | |
| Wisconsin | 19.2¢ | $96 | |
| Wyoming | 14.7¢ | $73 |
Certified models closest in efficiency
| Model | kWh/yr | $/yr (US avg) |
|---|---|---|
| BLACK+DECKER BD10NWES | 500 | $94 |
| Century RXTS-101A | 500 | $94 |
| Comfort Aire RXTS-101A | 500 | $94 |
| Danby DAC100B8IWDB-6 | 500 | $94 |
| DELLA 048-TL-W10KI | 500 | $94 |
| ELEMENT EHWR10BE | 500 | $94 |
Run your own numbers
Your rate, your numbers
- Per day
- 26¢
- Per month
- $7.85
- Per year
- $94
500 kWh/yr × 18.8¢/kWh = $94/yr
Prefilled with this model's certified 500 kWh/yr — adjust if your usage differs from the DOE test basis. The certified annual kWh assumes 750 cooling hours per year (the DOE standard). In hot climates real usage can run well above that; in mild ones, below.
Questions, answered with the data
- How much electricity does the Keystone KSTAW10INV use?
- ENERGY STAR certifies the Keystone KSTAW10INV at 500 kWh per year. The certified annual kWh assumes 750 cooling hours per year (the DOE standard). In hot climates real usage can run well above that; in mild ones, below.
- How much does the Keystone KSTAW10INV cost to run per month?
- About $7.85 a month at the U.S. average residential rate (18.8¢/kWh) — 26¢ a day, or $94 a year. Your state's rate moves this up or down; see the table above.
- Is the Keystone KSTAW10INV energy efficient?
- It uses 6% less electricity than the median certified room air conditioner.
- What does the Keystone KSTAW10INV cost to run in the cheapest vs. priciest state?
- At current residential rates it costs about $62 a year in North Dakota (12.3¢/kWh) and $233 in Hawaii (46.6¢/kWh).