WattCost

Data through April 2026

Room Air Conditioners · 11 certified models

Keystone

Keystone: 11 ENERGY STAR certified models in this data, running $75 to $255 a year at the U.S. average electricity rate — a median of $113, versus $100 across every certified room air conditioners.

All certified models

Keystone, ranked by certified annual kWh
#ModelkWh/yr$/yr (US avg)
1Keystone KSTAW081WA400$75
2Keystone KSTAW08INV400$75
3Keystone KSTAW08INV-HCmost efficient414$78
4Keystone KSTAW101WA500$94
5Keystone KSTAW10INV500$94
6Keystone KSTAW121WA600$113
7Keystone KSTAW12INV600$113
8Keystone KSTAW12INV-HC677$127
9Keystone KSTAW141WA700$132
10Keystone KSTAW182WA900$169
11Keystone KSTAW242WA1,353$255

Other brand facets

Questions, answered with the data

How much does it cost to run Keystone room air conditioners?
Among 11 certified models in this data, Keystone room air conditioners cost $75 to $255 a year to run at the U.S. average electricity rate (18.8¢/kWh) — a median of $113.
Do Keystone room air conditioners cost more or less than the average room air conditioner?
The median model here runs $113 a year, 13% more than the $100 median across all certified room air conditioners.
What's the cheapest model among Keystone room air conditioners?
The Keystone KSTAW081WA costs about $75 a year at the U.S. average rate (400 kWh/yr) — the lowest certified figure in this group.
What does the certified annual-kWh figure assume for room air conditioners?
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.

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