#1 Window Most Efficient
Kühl KHVL28B35B
28,300 BTU · 1494.7 kWh/season
6 25,000+ BTU Window & Wall Air Conditioners, Ranked by Running Cost
Room air conditioners (window and through-the-wall) with rated cooling capacity 26,000 BTU/h and above, sold in the US. Window and through-the-wall units are mixed and tagged below. Ranked cheapest to run first, estimated at 18.31¢/kWh over a 750-hour cooling season (July 2026 rate).
6 ENERGY STAR certified models, from about $274 to $384 a cooling season to run at the US average electricity rate. This assumes 750 hours of cooling a year, ENERGY STAR's test assumption for a typical season — not continuous, year-round use. See how we calculate running costs.
Top 5 cheapest to run
#2 Window Most Efficient
Kühl KCVL28B30B
28,900 BTU · 1570.7 kWh/season
#3 Window Most Efficient
Friedrich KCVL28B30A
28,900 BTU · 1642 kWh/season
#4 Window
Friedrich KHVL28B35A
28,200 BTU · 1678.6 kWh/season
#5 Window Most Efficient
Kühl KCVL36B30B
33,000 BTU · 1847 kWh/season
All 6 models
| Rank | Brand | Model | Mount | BTU | Energy use | Est. cost/season |
|---|---|---|---|---|---|---|
| 1 | Kühl Most Efficient | KHVL28B35B | Window | 28,300 | 1494.7 kWh/season | $274 |
| 2 | Kühl Most Efficient | KCVL28B30B | Window | 28,900 | 1570.7 kWh/season | $288 |
| 3 | Friedrich Most Efficient | KCVL28B30A | Window | 28,900 | 1642 kWh/season | $301 |
| 4 | Friedrich | KHVL28B35A | Window | 28,200 | 1678.6 kWh/season | $307 |
| 5 | Kühl Most Efficient | KCVL36B30B | Window | 33,000 | 1847 kWh/season | $338 |
| 6 | Friedrich | KCVL36B30A | Window | 34,100 | 2096.3 kWh/season | $384 |