How much does it cost to run a pool pump 12 hours a day?
Running a 1,500 watt pump 12 hours a day uses 18 kWh a day, which at an example $0.17 per kWh costs $3.06 a day, about $91.80 a month and $550.80 over a 180-day season.
How to work it out
- 1,500 W × 12 h ÷ 1,000 = 18 kWh a day
- 18 kWh × $0.17 = $3.06 a day × 30 = $91.80 a month; × 180 days = $550.80
- Variable speed at 50%: 1,500 W × 0.5³ = 188 W, for 12 h ÷ 0.5 = 24 hours (same water moved)
- 188 W × 24 h = 4.5 kWh a day → $22.95 a month, saving $413.10 a season
Twelve hours a day is where a lot of single-speed pumps end up, often because the timer was set long after a bout of cloudy water and never moved back. It is half the clock, and on a single-speed pump it costs 50% more than an 8-hour schedule.
Adjust for your project
- Energy per day
- 18 kWh
- Cost per day
- $3.06
- Cost per season (days above)
- $550.80
- Energy per season
- 3,240 kWh
- Variable-speed: power at that speed
- 188 W
- Variable-speed: hours a day for the same water
- 24 hours
- Variable-speed: cost per month
- $22.95
- Variable-speed: saving per season
- $413.10
- Variable-speed: energy saved
- 75%
- 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.
1,500 W pump, 12 hours a day, by days a year
| Days a year | Cost per season (days above) | Energy per season | Variable-speed: saving per season |
|---|---|---|---|
| 90 days | $275.40 | 1,620 kWh | $206.55 |
| 120 days | $367.20 | 2,160 kWh | $275.40 |
| 150 days | $459.00 | 2,700 kWh | $344.25 |
| 180 days | $550.80 | 3,240 kWh | $413.10 |
| 240 days | $734.40 | 4,320 kWh | $550.80 |
| 365 days | $1,116.90 | 6,570 kWh | $837.68 |
Is 12 hours a day worth it?
At 1,500 W, twelve hours is 18 kWh a day and about 540 kWh a month. Before paying for that, check what the water actually needs. Most pools only need one full turnover a day, and the DOE Building America guide treats one turnover in 24 hours as the minimum — not a dozen hours at full speed.
- When 12 hours makes sense. A small pump on a big pool, heavy bather loads, a heater or solar panels that need flow in daylight, or an algae clean-up. Once the water is clear, step back down.
- Single-speed vs variable-speed. If you need long run times every day, that is exactly where a variable-speed pump pays: at 50% speed the 12-hour turnover becomes 24 hours at about 188 W, 4.5 kWh a day, roughly $22.95 a month at the example rate.
- Halving the hours. Going from 12 to 6 hours on the same pump halves the bill; DOE’s Florida example saved 60% on run time alone.
- Check the turnover. The pool pump size calculator shows how many gallons per minute your pool needs; dividing the volume by your pump’s real flow gives the hours.
Compare the shorter schedule on how much it costs to run a pool pump 8 hours a day. For the whole pool budget, with heat, chemicals and water, see how much it costs to run a pool per month.
Different size? Use the full Pool Pump Cost Calculator.
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
What does 12 hours a day cost on a 1 kW pump?
It uses 12 kWh a day, about $61.20 a month at the example $0.17 per kWh.
What does running a pool pump 24 hours a day cost?
With the 1,500 W example pump, 36 kWh a day: about $183.60 a month and $1,101.60 a season at $0.17 per kWh.
Other common sizes
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.