How much does it cost to run a pool pump 8 hours a day?
A 1,500 watt pump running 8 hours a day uses 12 kWh a day. At an example rate of $0.17 per kWh that is $2.04 a day, about $61.20 a month, or $367.20 over a 180-day season.
How to work it out
- 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
Eight hours is a common single-speed schedule: long enough to turn most pools over once, short enough to stay off overnight. The example here uses a 1,500 W pump and $0.17 per kWh; both are examples, so put in your own pump’s watts and the rate from your bill.
Adjust for your project
- 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%
- 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, 8 hours a day, by electricity rate
| Rate per kWh | Cost per day | Cost per month (30 days) | Cost per season (days above) | Variable-speed: cost per month |
|---|---|---|---|---|
| $0.10 | $1.20 | $36.00 | $216.00 | $9.00 |
| $0.15 | $1.80 | $54.00 | $324.00 | $13.50 |
| $0.20 | $2.40 | $72.00 | $432.00 | $18.00 |
| $0.25 | $3.00 | $90.00 | $540.00 | $22.50 |
| $0.30 | $3.60 | $108.00 | $648.00 | $27.00 |
| $0.40 | $4.80 | $144.00 | $864.00 | $36.00 |
Where the 8-hour cost goes
Every hour at 1,500 W is 1.5 kWh, so eight hours is 12 kWh a day — about 360 kWh a month. The pump draws the same power in the first hour as the eighth, so the cost scales in a straight line with run time: six hours costs three-quarters as much, ten hours a quarter more.
- Could it be fewer? DOE suggests starting at 6 hours of filtration a day and adding half an hour at a time only if the water isn’t clear. Dropping from 8 to 6 hours would save a quarter of this bill.
- The variable-speed version. At half speed a matching pump draws about 188 W and runs 16 hours to move the same water: 3 kWh a day, roughly $15.30 a month at the example rate. That is the 75% saving the affinity laws predict.
- Your real watts. A 1,500 W figure is only an example. A 1 hp and a 2 hp pump differ by about 750 W of shaft power alone (1 hp = 746 W); read the spec sheet or meter it.
- Rate matters as much as hours. Doubling the rate doubles every figure. Time-of-use plans can make the same 8 hours cheaper at night.
For a longer schedule, see how much it costs to run a pool pump 12 hours a day. To check whether 8 hours is even the turnover your pool needs, use what size pump for a 20,000 gallon pool as a worked example.
Different size? Use the full Pool Pump Cost Calculator.
What you’ll need
- 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) - 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) - 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 8 hours a day cost at $0.30 per kWh?
With the same 1,500 W pump, about $108.00 a month ($3.60 a day).
What does a 2,000 W pump cost to run 8 hours a day?
It uses 16 kWh a day, about $81.60 a month at the example $0.17 per kWh.
What if I cut it to 6 hours a day?
About $45.90 a month at the example rate, $275.40 over a 180-day season.
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.