Pool pump cost calculator: what does my pump cost to run?
Enter the pump’s power draw, the hours it runs and your electricity rate. The rate and power below are examples — put in your own from your bill and the pump’s spec sheet.
Enter your measurements
- Energy per day
- 12 kWh
- Cost per day
- $2.04
- Cost per season (days above)
- $367.20
- Energy per season
- 2,160 kWh
- Variable-speed: power at that speed
- 188 W
- Variable-speed: hours a day for the same water
- 16 hours
- Variable-speed: cost per month
- $15.30
- Variable-speed: saving per season
- $275.40
- Variable-speed: energy saved
- 75%
1,500 W × 8 h ÷ 1,000 = 12 kWh a day
12 kWh × $0.17 = $2.04 a day × 30 = $61.20 a month; × 180 days = $367.20
Variable speed at 50%: 1,500 W × 0.5³ = 188 W, for 8 h ÷ 0.5 = 16 hours (same water moved)
188 W × 16 h = 3 kWh a day → $15.30 a month, saving $275.40 a season
- The variable-speed figure is the ideal affinity-law result for a pump whose full-speed draw matches yours. Real pumps land near it — DOE’s measured pump drew 250 W at half speed against 2,000 W at full, exactly one-eighth — but check the model’s own wattage at the speed you set. Heaters, salt cells and cleaners may need a minimum speed.
Quick answers for common sizes
| Example | Answer |
|---|---|
| How much it costs to run a pool pump 8 hours a day | $61.20 |
| How much it costs to run a pool pump 12 hours a day | $91.80 |
Cost by hours a day (pump and rate above)
| Hours a day | Energy per day | Cost per day | Cost per month (30 days) | Variable-speed: cost per month |
|---|---|---|---|---|
| 4 hours | 6 kWh | $1.02 | $30.60 | $7.65 |
| 6 hours | 9 kWh | $1.53 | $45.90 | $11.48 |
| 8 hours | 12 kWh | $2.04 | $61.20 | $15.30 |
| 10 hours | 15 kWh | $2.55 | $76.50 | $19.13 |
| 12 hours | 18 kWh | $3.06 | $91.80 | $22.95 |
| 24 hours | 36 kWh | $6.12 | $183.60 | $22.95 |
A pool pump is often one of the bigger electricity users in a house with a pool, because it runs for hours every day of the season. The cost is simple arithmetic: power × hours = energy, and energy × your rate = money. What makes the difference is the two things you control: how many hours, and how fast.
How the pool pump cost calculator works
kWh per day = watts × hours ÷ 1,000 cost per day = kWh × price per kWh per month = per day × 30 · per season = per day × days variable speed at speed s (fraction of full): power = full power × s³ · hours = your hours ÷ s kWh per day = full power × s² × your hours ÷ 1,000
The variable-speed part uses the pump affinity laws Pentair sets out: flow is proportional to speed, head to speed squared and power to speed cubed. Halve the speed and the pump draws one-eighth of the power (ENERGY STAR’s figure; Pentair calls it an 87% cut), but moves half the water, so it runs twice as long to move the same amount. One-eighth the power for twice the time is a quarter of the energy — a 75% saving for the same turnover.
Typical numbers
- Power. The single-speed pump measured in the DOE Building America guide drew 2,000 W at full speed (3,450 rpm), 593 W at 2,400 rpm, 250 W at 1,800 rpm and 74 W at 1,200 rpm. Your pump’s spec sheet or a meter gives your real figure.
- A whole year. DOE’s Florida example pool used 3,000 kWh a year for pumping. A smaller pump saved 40%, fewer hours 60%, and both together 75%.
- Same pool, two pumps. In the Building America worked example, a 25,000-gallon pool used 12.6 kWh a day on a single-speed pump and 2.2 kWh a day with a variable-speed pump at 22 gpm (116 W) for 19 hours.
- Certified pumps. ENERGY STAR says certified in-ground pumps use 20% less energy than standard models, and above-ground models 11% less.
Worked examples
Two run times people ask about have their own pages, both with the same example pump and rate: how much it costs to run a pool pump 8 hours a day and how much it costs to run a pool pump 12 hours a day. Adding heat, chemicals and water is the pool running cost calculator, with an example of what a pool costs per month.
Ways to cut the bill
- Run fewer hours. DOE suggests 6 hours of filtration a day as a starting point, adding half an hour at a time if the water isn’t clear. ENERGY STAR notes that 6 hours instead of 24 cuts energy use 75%.
- Run slower and longer. A variable-speed pump at low speed for more hours moves the same water for a fraction of the energy. Use the pool pump size calculator to find the flow your pool actually needs.
- Lower the resistance. A clean filter and baskets, larger pipe and fewer tight bends cut the pump’s work; DOE puts the saving at up to 40%.
- Use cheaper hours. If your utility has time-of-use rates, a timer can move the run time to the cheap part of the day.
What you’ll need
- Variable-speed pool pumpPremium price
Runs slower for longer and uses far less electricity for the same turnover. Check it suits your pipe size and filter.
See options on Amazon (opens in a new tab) - Pool pump timerBudget price
Runs a single-speed pump only as long as the water needs, ideally in off-peak hours.
See options on Amazon (opens in a new tab) - Solar cover (bubble cover)Mid-range price
The cheapest heating upgrade there is: cuts evaporation and holds heat in overnight. Buy the size up and trim it.
See options on Amazon (opens in a new tab)
As an Amazon Associate we earn from qualifying purchases. Links to products are affiliate links — they cost you nothing extra and help keep these calculators free.
Frequently asked questions
How many watts does a pool pump use?
It depends on the pump and the speed. The single-speed pump measured in the DOE Building America guide drew 2,000 W at full speed; at 1,800 rpm the same pump drew 250 W. Check your spec sheet, or measure with a plug-in or clamp meter.
Is it cheaper to run a pool pump at night?
Only if your utility charges less at night. On a flat rate the cost per kWh is the same at any hour. On a time-of-use plan, running in the off-peak window can cut the cost without changing the energy used.
How much does a variable-speed pump save?
By the affinity laws, half speed for twice as long uses a quarter of the energy — 75% less for the same water moved. In DOE’s worked example a 25,000-gallon pool went from 12.6 to 2.2 kWh a day. Your saving depends on how slow you can run and still meet heater, cleaner and salt-cell flow needs.
Why does the calculator double the hours at half speed?
Because flow is proportional to speed. At half speed the pump moves half as many gallons per minute, so it needs twice the hours to turn the pool over the same number of times. Power falls far faster than flow, which is where the saving comes from.
Related guides
Sources
- US DOE Energy Saver — Choosing, installing and operating an efficient swimming pool pump (archived) (opens in a new tab) — Start at 6 hours of filtration a day and add half-hour steps if needed; a Florida study pool used 3,000 kWh a year, saving 40% with a smaller pump, 60% with less run time and 75% with both.
- ENERGY STAR — Pool pumps (opens in a new tab) — Halving pump speed uses one-eighth as much energy; certified in-ground pumps use 20% less energy than standard models, above-ground 11%; 6 hours a day instead of 24 cuts energy use 75%.
- Pentair — Pump affinity laws and energy savings (opens in a new tab) — Flow ∝ speed, head ∝ speed², power ∝ speed³; halving speed cuts consumption by 87%.
- US DOE Building America — Measure guideline: replacing single-speed pool pumps with variable-speed pumps (Hunt & Easley, 2012) (opens in a new tab) — One pump measured at 3,450 rpm 2,000 W, 1,800 rpm 250 W, 1,200 rpm 74 W. Worked example: a 25,000 gallon pool at 12.6 kWh a day on a single-speed pump vs 2.2 kWh a day for a variable-speed pump at 22 gpm, 116 W, 19 hours.