What does it cost to cool a home in summer?
Reviewed
EIA data · June 2026Cooling is the largest summer electricity load in most US homes, and the gap between the cheapest and most expensive way to stay comfortable is larger than in winter.
It is also the season where one very cheap appliance and one very expensive one are routinely treated as substitutes when they do completely different jobs.
Cost over a three-month season
At the U.S. average of 18.34¢ per kilowatt-hour, with duty cycles raised for in-season operation and each appliance at its own default usage. Central air conditioner costs about 52× what ceiling fan does — though these are not always like for like. Whole-house heating and a single warm bed are different jobs, and the table ranks cost, not suitability.
| Appliance | Typical W | In-season duty | Per season |
|---|---|---|---|
| Central air conditioner | 3,500 | 90% | $422 |
| Pool pump | 1,500 | 100% | $201 |
| Portable air conditioner | 1,100 | 100% | $147 |
| Ductless mini-split | 900 | 90% | $136 |
| Window air conditioner | 900 | 100% | $120 |
| Dehumidifier | 500 | 90% | $90.37 |
| Box fan | 75 | 100% | $10.04 |
| Ceiling fan | 60 | 100% | $8.03 |
How the seasonal figures are built. Cooling appliances cycle far more during a heatwave than their annual baseline implies. The figures below apply a 1.5x multiplier to each appliance's baseline duty cycle to approximate peak-summer operation. Fans, which do not cycle, are unaffected.
A fan and an air conditioner are not alternatives
A ceiling fan costs roughly one fifteenth of what a window air conditioner costs to run, which makes it look like an obvious substitute. It is not one.
An air conditioner removes heat from a room. A fan moves air across skin, which makes a person feel two to four degrees cooler while changing the room temperature not at all. In an empty room a fan does nothing but cost money.
The genuinely useful combination is both. A fan lets you raise the thermostat several degrees at the same comfort, and that saving is far larger than the fan costs to run.
The single-hose portable problem
Portable air conditioners are the least efficient common way to cool a room, and the reason is structural rather than a matter of build quality.
A single-hose unit blows conditioned indoor air out of the window. That air has to be replaced, and it is replaced by warm unconditioned air drawn in through every gap in the building. The unit then cools air it helped bring inside.
Dual-hose models take their exhaust air from outside and avoid this. If you are choosing a portable, that distinction matters more than the BTU rating.
The appliance that raises your cooling bill
A dehumidifier is far cheaper to run than an air conditioner and genuinely helps a damp room feel more comfortable. But it releases the heat it removes back into the room.
In a space you are also air conditioning, that heat becomes a load your air conditioner has to remove — so you pay for it twice.
In an unconditioned basement, where the extra heat does not matter, a dehumidifier is exactly the right tool and much cheaper than cooling the space.
The load that has nothing to do with comfort
In homes that have one, a pool pump is often the largest single electricity consumer of the summer — larger than the air conditioning it sits next to on this list.
Power rises roughly with the cube of flow rate, so a variable-speed pump running at half speed for twice as long uses a small fraction of the electricity for the same water turnover.
Most pools are also pumped for more hours than filtration actually requires, which makes the timer setting one of the highest-leverage numbers in the whole house.