Fan Power Cost
See the running cost of a fan compared by speed setting.
About Fan Power Cost
Fans draw different wattage at each speed, so the spread between low and high matters. Multiplying that draw by run time and the rate gives the monthly cost. Choosing a lower fan speed throughout the year can save more than many people expect, especially with fans left running at night.
Formula
Fan Power Cost
Monthly cost = watts x hours x 30 x rate / 1000
- watts
- Power draw at the chosen speed
Worked example
With the default values below, Fan Power Cost returns Low Speed Monthly of $0.54. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Low speed wattsminimum 0 watts
- 15 watts
- High speed wattsminimum 0 watts
- 65 watts
- Run per dayminimum 0 hours
- 8 hours
- Electricity rateminimum 0 $/kWh
- 0.15 $/kWh
Results
- Low Speed Monthly
- $0.54
- High Speed Monthly
- $2.34
- Monthly Difference
- $1.80
- Low Speed Annual
- $6.48
Step by step
- 1Values used
- 2Fan Power Cost
- 3Low Speed Monthly= 0.54
- 4High Speed Monthly= 2.34
- 5Monthly Difference= 1.80
- 6Low Speed Annual= 6.48
Assumptions and limits
- The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Fan Power Cost calculated?
Monthly cost = watts x hours x 30 x rate / 1000 Fans draw different wattage at each speed, so the spread between low and high matters. Multiplying that draw by run time and the rate gives the monthly cost.
Why does Fan Power Cost matter?
Choosing a lower fan speed throughout the year can save more than many people expect, especially with fans left running at night.
What values do I need to enter?
This calculator takes 4 inputs: Low speed watts, High speed watts, Run per day, Electricity rate. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.