Ceiling fan
How much electricity does a ceiling fan use?
15–75 W · 90% cheaper than AC · $2–$10 per month
Ceiling fans are the cheapest cooling available: most models draw 15–75 W depending on speed, which is roughly one percent of a central air conditioner.
Actual wattage by size and speed
- 42-inch, low: 10–20 W
- 52-inch, medium: 30–50 W
- 52-inch, high: 60–80 W
- Compare: a window AC is 900 W, central air 3,000–4,000 W
The thermostat rule
A ceiling fan does not cool the air. It cools people by increasing the rate of evaporation from skin. That means running a fan in an empty room wastes 100% of its energy — and the effect is worth roughly 3–4°C of apparent temperature, so you can set the thermostat that much higher while still comfortable.
Winter trick
In winter, set the fan to run clockwise at low speed. That pulls cool air up and pushes warm air down from the ceiling, redistributing heat from your heating system without adding a heating load of its own. It costs about $1 a month.
DC motor fans
DC-motor fans use 60–70% less energy than AC-motor fans at the same airflow and usually run silently. If you are buying, this is the worthwhile upgrade — over a season of daily use the difference is measured in tens of kWh.
Frequently asked questions
How many watts does a ceiling fan use?
15–75 W. The figure on the rating label is the maximum draw; actual use varies with settings, age and usage pattern.
How much does it cost to run a ceiling fan per month?
With the defaults above it comes to the monthly figure shown in the calculator. At 16.5¢/kWh — the US residential average — that is a realistic middle estimate. Your own bill may be 30% lower or higher depending on state.
Is it cheaper to run a ceiling fan at night?
Only if your utility offers a time-of-use plan and you avoid the 4pm–9pm peak window. On a flat-rate plan, the time of day makes no difference to the total.
Does the calculator account for real-world duty cycles?
Not automatically — you enter the effective hours yourself. For compressing appliances like refrigerators and AC units, enter the running watts and roughly the proportion of time the compressor is on, which is usually 30–50%.
Will a newer ceiling fan actually save money?
Compare the kWh figure in the calculator against an Energy Star model's stated annual use. If the difference is a few hundred kWh a year, the payback on a replacement is usually long; if it is over 500 kWh, it is worth pricing out.