What a pool pump costs to run
A pump's cost is its watts × hours × your price per kWh, and the pump type decides the watts. Variable-speed pumps can run slowly for filtration; because pump power falls with the cube of speed, half the speed uses about one-eighth of the power(ENERGY STAR). That is why they cost so much less than single-speed pumps that always run flat out.
Worked example: an ENERGY STAR in-ground variable-speed pump averages 109 W on low and 787 W on high. Ten hours on low plus two on high is 2.66 kWh a day — $0.48 a day or $14.74 a month at 18.19¢/kWh. A 1,750 W single-speed pump for 8 hours uses 14 kWh a day: $77.47 a month.
Pool pump power by type
| Pump | Watts | 8 h a day, per month |
|---|---|---|
| In-ground variable speed, low | 109 | $4.83 |
| In-ground variable speed, high | 787 | $34.82 |
| Above-ground variable speed, low | 97 | $4.29 |
| Above-ground variable speed, high | 572 | $25.33 |
| Booster (pressure-side cleaner) | 916 | $40.55 |
| Single speed, 1.5 hp (estimate) | 1,750 | $77.47 |
Variable-speed and booster figures are averages of ENERGY STAR certified pumps at the federal test points. ENERGY STAR lists no in-ground single-speed filter pumps; the 1.5 hp figure is the typical 1,500–2,000 W range of older pumps, so read your motor plate or the pump's display for a real number.
Hours and season
Pools in warm states often run all year; northern pools run only through the swimming season. Set the months in the calculator, and for a variable-speed pump split the day between a short high-speed block (for skimming, a heater or a cleaner) and long low-speed filtration. Running longer on low usually costs less than running a shorter time on high.
Ways to cut the cost
- Replace a single-speed pump with a variable-speed model; ENERGY STAR estimates certified in-ground pumps save about $50 a year over standard models.
- Program high speed only for the tasks that need it.
- Keep the skimmer basket and filter clean so the water turns over in fewer hours.
- On a time-of-use plan, schedule filtration outside the peak window.
Common mistakes
- Using horsepower × 746 W. Motor horsepower isn't electrical input; the pump's display or a meter tells you the real watts.
- Pricing a variable-speed pump at full speed all day. Most of its hours should be at low speed.
- Forgetting the booster pump. A pressure-side cleaner's booster can draw more than the main pump on low.
Adding a spa? See the hot tub cost calculator, or check your state's price per kWh.