WattCost

Data through April 2026

Running cost · Room Air Conditioners · ENERGY STAR certified

Keystone KSTAW242WA

Under the DOE test basis of 750 hours a year, the Keystone KSTAW242WA draws 1,353 kWh — about $255 at the U.S. average rate, concentrated in the months you actually run it. It sits near the bottom of the certified table — using 154% more than the median room air conditioner (rank 376 of 396) — so the state you live in matters more than usual. The same unit costs $167 a year in North Dakota but $631 in Hawaii — electricity rates, not the appliance, make the difference.

Estimated annual running cost · U.S. average rate 18.8¢/kWh

$255/yr

$52 · cheapest certified room air conditioners$395 · priciest
Per month
$21.24
Per day
70¢
Certified use
1,353 kWh/yr
Cooling capacity
24,000 BTU/hr
CEER
13.3
Mounting
Does Not Straddle Window or Windowsill
Variable-speed compressor
Yes
274 kWh2,096 kWh
Where the Keystone KSTAW242WA (▮) sits among all 396 certified room air conditioners, by annual kWh

What it costs in every state

Keystone KSTAW242WA: 1,353 kWh/yr × each state's average residential rate (EIA)
StateRate ¢/kWhThis model $/yrRelative cost
Alabama17.4¢$236
Alaska27.4¢$370
Arizona15.5¢$210
Arkansas14.2¢$192
California35.3¢$477
Colorado16.5¢$224
Connecticut32.2¢$436
Delaware18.8¢$254
District of Columbia25.4¢$344
Florida15.4¢$208
Georgia15.4¢$208
Hawaiipriciest46.6¢$631
Idaho12.7¢$172
Illinois20.5¢$277
Indiana17.9¢$242
Iowa13.9¢$188
Kansas15.8¢$214
Kentucky15.0¢$203
Louisiana14.4¢$195
Maine28.4¢$385
Maryland22.1¢$299
Massachusetts29.4¢$399
Michigan21.4¢$289
Minnesota16.4¢$222
Mississippi16.8¢$227
Missouri14.0¢$190
Montana13.9¢$188
Nebraska13.3¢$180
Nevada14.3¢$193
New Hampshire27.2¢$369
New Jersey23.5¢$318
New Mexico15.2¢$205
New York29.4¢$399
North Carolina16.3¢$220
North Dakotacheapest12.3¢$167
Ohio19.5¢$264
Oklahoma13.3¢$180
Oregon15.8¢$214
Pennsylvania21.5¢$291
Rhode Island28.3¢$383
South Carolina17.1¢$231
South Dakota14.5¢$197
Tennessee14.9¢$202
Texas17.0¢$230
Utah13.3¢$180
Vermont24.6¢$332
Virginia17.4¢$235
Washington14.4¢$194
West Virginia16.1¢$217
Wisconsin19.2¢$260
Wyoming14.7¢$199

Certified models closest in efficiency

room air conditioners within reach of 1,353 kWh/yr
ModelkWh/yr$/yr (US avg)
Comfort Aire RADS-253R031,353$255
Frigidaire FHWW245WE21,353$255
Keplerx KBRC24RSVE21,353$255
Midea MAW24R2VWT1,353$255
Midea MAW24RV1CWT1,353$255
Midea MAW24S2VWT-A1,353$255

Run your own numbers

Your rate, your numbers

Per day
70¢
Per month
$21.23
Per year
$255

1,353 kWh/yr × 18.8¢/kWh = $255/yr

Prefilled with this model's certified 1,353 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 KSTAW242WA use?
ENERGY STAR certifies the Keystone KSTAW242WA at 1,353 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 KSTAW242WA cost to run per month?
About $21.24 a month at the U.S. average residential rate (18.8¢/kWh) — 70¢ a day, or $255 a year. Your state's rate moves this up or down; see the table above.
Is the Keystone KSTAW242WA energy efficient?
It uses 154% more electricity than the median certified room air conditioner, which puts it among the least efficient certified models.
What does the Keystone KSTAW242WA cost to run in the cheapest vs. priciest state?
At current residential rates it costs about $167 a year in North Dakota (12.3¢/kWh) and $631 in Hawaii (46.6¢/kWh).

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