Electric fans are usually cheap to run because most use far less power than heaters or portable air conditioners. The exact cost depends on wattage, speed setting, hours used and your electricity tariff.
An electric fan is one of the cheaper cooling appliances to run because it usually uses tens of watts rather than hundreds or thousands. The trade-off is that a fan cools people through airflow; it does not remove heat from the room like air conditioning.
Contents
- 1 Key Takeaways
- 2 The Cost Formula
- 3 Example Fan Running Costs
- 4 Case Study: Running A Fan Through A Heatwave
- 5 Expert Insights From Our HVAC Engineers
- 6 Frequently Asked Questions
- 6.1 How Much Does An Electric Fan Cost To Run?
- 6.2 Does Fan Speed Affect Running Cost?
- 6.3 Is A Tower Fan More Expensive Than A Desk Fan?
- 6.4 Can A Fan Cool A Room Down?
- 6.5 Is A Fan Cheaper Than Portable Air Conditioning?
- 6.6 Should I Leave A Fan Running In An Empty Room?
- 6.7 Do Dusty Fans Cost More To Run?
- 6.8 How Do I Calculate My Fan’s Running Cost?
- 7 Summing Up
Key Takeaways
- Most domestic fans use roughly 20 to 75 W depending on size and speed.
- A 50 W fan running for 10 hours uses 0.5 kWh.
- Fans are far cheaper to run than portable air conditioners, but they do not lower room temperature.
- Speed setting, timer use and cleaning affect comfort and cost.
- Leaving a fan on in an empty room is usually wasteful because fans cool people, not rooms.
The Cost Formula
Watts divided by 1000, multiplied by hours used, multiplied by the electricity unit rate. A 50 W fan running for 10 hours uses 0.5 kWh.
For current UK context, Ofgem lists an average electricity unit rate of 24.67p per kWh from 1 April to 30 June 2026 for Direct Debit customers in England, Scotland and Wales. Your tariff may be higher or lower, so the most accurate figure is always the unit rate on your own bill.
Typical Fan Wattages
Desk fans often use 20 to 35 W, tower fans 40 to 60 W, and larger pedestal fans around 50 to 75 W. High settings use more.
| Fan Type | Typical Wattage | 8 Hours At 24.67p/kWh | 24 Hours At 24.67p/kWh |
|---|---|---|---|
| Small desk fan | 25 W | About 5p | About 15p |
| Tower fan | 50 W | About 10p | About 30p |
| Pedestal fan | 75 W | About 15p | About 44p |
| Large or industrial fan | 150 W | About 30p | About 89p |
Fans Vs Portable AC
A fan may cost pennies for a long evening, while a portable AC can use 900 to 1500 W. The trade-off is that fans do not lower room temperature.
This is the key decision point. A fan is excellent value when airflow is enough to make you comfortable. If the room itself is still too hot, especially for sleeping or for vulnerable people during a heatwave, the lower running cost does not mean it is the right tool. Our guide to ways to cool down a room covers lower-cost cooling steps that can make a fan more effective before you consider active cooling.
How To Use A Fan Efficiently
Use timers, clean dust from grilles, position the fan where airflow reaches people and use lower speeds when they are enough.
Fans cool people, not rooms. Leaving one running in an empty bedroom for hours before you go to bed usually wastes electricity because the air temperature barely changes. A better approach is to keep solar heat out during the day, ventilate when outdoor air is cooler, then run the fan where the airflow reaches you.
For safety guidance, see how long you can leave an electric fan on.
Example Fan Running Costs
| Fan Type | Typical Power | 10 Hours Of Use | Cost At 25p/kWh |
|---|---|---|---|
| Small desk fan | 25 W | 0.25 kWh | About 6p |
| Tower fan | 50 W | 0.5 kWh | About 13p |
| Large pedestal fan | 75 W | 0.75 kWh | About 19p |
| Portable AC comparison | 1000 W | 10 kWh | About £2.50 |
The difference between 25p/kWh and the Ofgem April to June 2026 average of 24.67p/kWh is tiny for a fan, because the wattage is low. The bigger difference comes from the fan itself: a small 25 W desk fan used carefully costs far less than a large industrial-style fan left running all day.
How To Get More Cooling From The Same Fan
Use the fan where airflow reaches your body, not hidden in a corner. In the evening, position it to draw cooler air from a shaded window if outdoor air is cooler than indoor air. During the hottest part of the day, close blinds and keep hot air out.
Clean the grille and blades. Dust reduces airflow and can make the fan noisier. Use oscillation when sharing airflow across a room, and fixed direction when one person needs direct cooling.
Placement is often more important than speed. A fan aimed across a bed, desk or sofa on a medium setting can feel better than a fan blasting into an empty corner on high. If the room has two openings and the outside air is cooler, one fan can help move warm air out or pull cooler air through. If outside air is hotter, close windows and blinds until the temperature drops.
When A Fan Is Not Enough
A fan will not solve a room that stays dangerously hot. It does not reduce air temperature, remove humidity or cool an empty room for later. In heatwaves, vulnerable people may need active cooling, shaded rooms, hydration and support rather than relying only on airflow.
What Changes The Cost In Real Use
Speed setting is the main variable after wattage. Some fans use noticeably more power on turbo settings than on a gentle sleep mode. Oscillation may add a small amount, but it is usually minor compared with motor power.
The bigger issue is whether the fan is actually helping. A fan left running in an empty room costs money without improving comfort. A fan aimed well at an occupied desk, bed or sofa can provide useful cooling for very little electricity.
Comfort Vs Temperature
A fan can be excellent value when the room temperature is warm but not extreme. It improves comfort by moving air across skin. If the room itself is storing heat from sun-facing glass, poor insulation or a hot loft space above, a fan may feel less effective as the evening goes on. In that case, shading, ventilation timing and reducing heat gain matter as much as the fan wattage.
For bedrooms, a timer can keep costs and noise down. Running a fan for the first few hours of sleep may be enough once the room has cooled slightly. For home offices, shorter targeted use can be more effective than leaving the fan on continuously while you are away from the desk.
Case Study: Running A Fan Through A Heatwave
Background
A household ran a tower fan overnight during a warm week and worried it would add heavily to the bill.
What Changed
They checked the wattage label, used the timer and ran the fan on a lower night setting.
Result
The cost was modest compared with portable AC. The bigger comfort gain came from closing blinds during the day and ventilating when the outdoor air cooled.
Expert Insights From Our HVAC Engineers
One of our senior HVAC engineers with over 20 years of experience says fans are cheap because they move air rather than remove heat. That makes them excellent value for personal comfort, but limited in rooms that remain hot overnight.
He recommends using fans alongside shading and ventilation timing. Keep solar heat out during the day, then use the fan to move cooler air when outdoor temperatures drop.
He also notes that cleaning has a comfort value as well as a safety value. Dust on blades and grilles reduces airflow, increases noise and can make people turn the fan up unnecessarily. A clean fan on a lower setting often feels better than a dusty fan working harder.
For very long running periods, use the lowest effective speed and check the fan occasionally rather than treating it as completely fit-and-forget. That keeps costs low and helps catch rattles, dust build-up or cable problems early.
Frequently Asked Questions
How Much Does An Electric Fan Cost To Run?
Most domestic fans cost only pennies per hour because they use relatively little power. For example, a 50 W fan running for 10 hours uses 0.5 kWh. Multiply that by your electricity unit rate to get the cost.
Does Fan Speed Affect Running Cost?
Yes. Higher speeds normally use more electricity because the motor is working harder. The difference is still small compared with heaters or portable air conditioners, but using a lower comfortable speed saves a little over long periods.
Is A Tower Fan More Expensive Than A Desk Fan?
Usually a tower fan uses more electricity than a small desk fan because it has a larger motor and broader airflow. The difference is often only pennies over an evening, so choose based on the space and comfort you need.
Can A Fan Cool A Room Down?
A fan does not lower the room temperature. It cools people by moving air across skin and helping sweat evaporate. Once the fan is off, the room temperature is much the same unless you used it to move cooler outdoor air indoors.
Is A Fan Cheaper Than Portable Air Conditioning?
Yes, usually by a large margin. A fan may use 20 to 75 W, while a portable AC can use around 900 to 1500 W. The trade-off is that air conditioning actually removes heat and humidity from the room.
Should I Leave A Fan Running In An Empty Room?
Usually no. A fan cools people, not empty rooms, so running it when nobody is there wastes electricity. An exception might be using it briefly to move cooler evening air through a room.
Do Dusty Fans Cost More To Run?
Dust can reduce airflow, make the motor run hotter and make the fan noisier. The cost difference may be small, but cleaning improves comfort and reduces strain on the appliance.
How Do I Calculate My Fan’s Running Cost?
Find the wattage label, divide watts by 1000 to get kW, multiply by the hours used, then multiply by your electricity unit rate. For example, 40 W is 0.04 kW, so 10 hours uses 0.4 kWh.
Summing Up
An electric fan usually costs only pennies to run because most domestic models use tens of watts, not hundreds or thousands. The exact cost depends on wattage, speed, hours used and your tariff, but the formula is simple: watts divided by 1000, multiplied by hours, multiplied by your unit rate. The more important judgement is whether a fan is the right comfort tool. It is very cheap for personal airflow, but it will not cool an empty room or remove heat like air conditioning.
Updated