Pool Pump Electricity Cost Calculator

Related Calculators

Table of contents

• How to use
• Common mistakes
• Definitions
• Methodology
• Limitations & assumptions
• Sources

Watts: A measure of how much electric power the pump uses while it is running.
kWh: Kilowatt-hour, the energy unit commonly used on electric bills; 1 kWh is 1000 watts running for 1 hour [1].
Main pump power (watts): The wattage for the pump setting you use most often.
Electricity rate ($ per kWh): The price you pay for each kilowatt-hour of electricity.
Cost for an average running month: The estimated pump cost for 365 / 12 running days, or about 30.4167 days.
Average power while the pump is on: The blended wattage across the main setting and second setting, counting only the hours the pump runs.

Mistake: Entering horsepower instead of Main pump power (watts) .
Fix: Use running watts from the label, smart plug, or energy monitor, because watts plug directly into the electricity formula.

Mistake: Using the nameplate maximum for Main pump power (watts) when a variable-speed pump usually runs lower.
Fix: Use the watts for the speed you actually run most of the day, then use Second setting power (watts) for the short higher-speed period.

Mistake: Filling Second setting power (watts) but leaving Second setting run time (hours per day) at 0.
Fix: Fill both second-setting fields, or set both to 0 if you only want a one-setting estimate.

Mistake: Entering the total bill amount in Electricity rate ($ per kWh) .
Fix: Enter the price for one kWh, such as 0.18, not the full monthly bill.

Mistake: Setting Pump running days per year to 365 for a pool that is closed part of the year.
Fix: Use the number of days the pump actually runs, such as 180 for a seasonal pool.

• The estimate uses the schedule you enter. It does not know if your timer, automation system, freeze protection, or cleaning cycle runs extra hours.
• Cost for an average running month uses 365 / 12 days. A real calendar month can have 28, 29, 30, or 31 days.
• If your utility uses tiered or time-of-use pricing, Electricity rate ($ per kWh) should match the hours when the pump runs.
• Pump watts can change with speed, plumbing resistance, filter condition, and water features. A smart plug or energy monitor gives a better watt value than horsepower.
• The optional second setting handles one extra speed or booster schedule only. It is not a full hour-by-hour scheduler.
• The calculator estimates electricity cost only. It does not include water, chemicals, repairs, or pump replacement cost.

Calculation steps

The calculator treats each pump setting as watts multiplied by hours, then converts watt-hours to kilowatt-hours by dividing by 1000. Electric bills commonly use kWh as the energy unit [1].

daily_kwh = ((power_w * hours_day) + (second_power_w * second_hours_day)) / 1000

daily_cost = daily_kwh * electricity_rate

monthly_running_cost = daily_cost * (365 / 12)

selected_days_cost = daily_cost * days_per_year

selected_days_kwh = daily_kwh * days_per_year

main_cost_per_hour = (power_w / 1000) * electricity_rate

average_running_watts = (daily_kwh * 1000) / (hours_day + second_hours_day)

Mini-example

For a 1500 watt pump running 8 hours per day at $0.18 per kWh for 365 days, daily electricity is (1500 * 8) / 1000 = 12 kWh. Daily cost is 12 * 0.18 = $2.16. The average running month cost is $2.16 * 30.4167 = $65.70, and the 365-day cost is $788.40.

Second setting logic

The second setting is counted only when both Second setting power (watts) and Second setting run time (hours per day) are greater than 0. If only one second-setting field is filled, the calculator stops and asks you to fill both fields or set both to 0.