How much energy does a ceiling fan use?

that depends on the model

It depends on how many amps your fan pulls. Most newer models pull about 1 amp. Older models about 3. Assuming you have a newer model, 1 amp * 120 Volts = 120 Watts. 120 Watts/ 1000 Watts/KiloWatt = 0.12 kilowatts. Depending on where you live in the US, I assume, your electric cost is b/n $0.05—$0.16 per kilowatt-hour. Assuming you have 4, 60 watt light bulbs in your fan you are using 360 watts or 0.36 kilowatts per fan and lights. Per every hour you run your fan and all of your lights you are spending on average 0.36 kilowatts * $0.10 kilowatt-hour = $0.036 per hour.