Three reproducible seasonal scenarios
| Scenario | Published inputs | Annual energy | Annual cost |
|---|---|---|---|
| 600 W for six hours on 90 active days at 65% duty | 600 W; 6 h/active day; 90 active days/year; 65% duty; quantity 1; 1 W standby for 18 h on 365 standby days; $0.18/kWh | 217.170 kWh | $39.09 |
| 900 W for eight hours on 120 active days at 60% duty | 900 W; 8 h/active day; 120 active days/year; 60% duty; quantity 1; 2 W standby for 16 h on 365 standby days; $0.18/kWh | 530.080 kWh | $95.41 |
| 1,200 W for ten hours on 150 active days at 55% duty | 1,200 W; 10 h/active day; 150 active days/year; 55% duty; quantity 1; 2 W standby for 14 h on 365 standby days; $0.18/kWh | 1,000.220 kWh | $180.04 |
$0.18/kWh is an illustrative comparison rate, not a national or current market price. These schedules and duty cycles are transparent arithmetic fixtures.
Capacity and electrical input are different
BTU/h is cooling capacity; it is not electrical watts. Temperature, humidity, thermostat setting, room size, insulation, sunlight, capacity, efficiency, installation, window sealing and compressor cycling affect electricity use.
Do not apply unverified conversions from SEER, SEER2, EER, CEER or label values. Use the defined label method, electrical input or representative measured kWh for the specific model and conditions.
Measurement and limitations
Representative multi-hour or daily measured kWh is preferable where safely obtainable with correctly rated equipment. Record outdoor conditions, thermostat setting and duration. Results from one period do not guarantee another season or room.
Calculate your window AC’s seasonal electricity use
Related: ceiling fan · portable air conditioner · compare room-cooling electricity schedules · methodology · sources
Last reviewed: August 14, 2026