Seasonal Home Comfort	Wattage	Estimated Monthly Hours	Energy Use kwh/month	Cost/Month @ 11 cents/kwh
Air Conditioning (75% on time — 8 hours per day)
Central Air Conditioner, 24,000 Btu (2-ton), 10.0 SEER	2,400	180	432	$47.52
Central Air Conditioner, 36,000 Btu (3-ton), 10.0 SEER	3,600	180	648	$71.28
Central Air Conditioner, 48,000 Btu (4-ton), 10.0 SEER	4,800	180	864	$95.04
Room Air Conditioner, 6,000 Btu, 9.0 EER	667	180	120	$13.20
Room Air Conditioner, 9,000 Btu, 10.0 EER	900	180	162	$17.82
Heat Pump (Split System), 36,000 Btu, 10.0 SEER / 7.0 HSPF	3,600	180	648	$71.28
Space Heating
Electric Furnace, 10 kw	10,000	240	2,400	$264.00
Baseboard Heater, 6-foot section @ 250 watts/ft.	1,500	240	360	$39.60
Portable Space Heater (1000-watt, medium setting)	1,000	120	120	$13.20
Heating/Cooling System Support
Oil Furnace Burner Motor, 1/4 hp	220	240	53	$5.83
Forced-Air System Blower Fan, 1/2 hp	440	240	106	$11.66
Hydronic (Hot Water) Circulating Pump, 1/8 hp	110	240	26	$2.86
Fans
Whole-House Attic Fan, 30-inch	400	240	96	$10.56
Window Fan (dual-unit)	200	240	48	$5.28
Ceiling Paddle Fan, 4-foot (no lights)	100	240	24	$2.64
Portable Box Fan, 20-inch	100	120	12	$1.32
Oscillating Table Fan, 12-inch	35	120	4	$0.44
Air Quality
Humidifier	175	240	42	$4.62
Electrostatic Air Cleaner	50	240	12	$1.32
Dehumidifier	635	360	229	$25.19

 

KEY
SEER (Seasonal Energy Efficiency Ratio) – Used to rate the cooling efficiency of central air conditioners and heat pumps. A higher SEER rating means higher efficiency. Federal energy efficiency standards require a minimum of 10 SEER for newer units.

EER (Energy Efficiency Ratio) – Used to rate the efficiency of room air conditioners. A higher EER rating means higher efficiency. A unit EER rating of 9 is considered efficient, with ratings of 10 or more as highly efficient.

HSPF (Heating Season Performance Factor) – Used to rate the heating efficiency of heat pumps. A higher HSPF rating means higher efficiency.