If you have a pool and a single-speed pump, that pump is almost certainly the largest electricity consumer on your property, ahead of the air conditioning. It is also the appliance with the largest available saving of anything in a house, and the fix has been well understood for twenty years.
A single-speed pool pump draws around 1,500 W and typically runs eight hours a day, which is [hed_cost appliance=”pool-pump” period=”day”] a day at [hed_var key=”us_rate_cents” format=”cents”] per kWh and [hed_cost appliance=”pool-pump” period=”month”] a month. Over a 180-day season that is [hed_cost appliance=”pool-pump” period=”season”]. A variable-speed pump doing the same filtration typically costs a fifth to a quarter of that.
Why halving the speed saves three quarters of the energy
Pump power rises roughly with the cube of flow rate. Halve the speed and you use about an eighth of the power, while moving half the water. To filter the same total volume you run twice as long, so the arithmetic lands at roughly a quarter of the energy for the same turnover.
This is why variable-speed pumps win so decisively, and why running a single-speed pump for fewer hours is a much weaker version of the same idea. The single-speed pump has one setting, and that setting is far faster than filtration actually requires.
[hed_wattage_matrix appliance=”pool-pump”]Cost by daily runtime
[hed_hours_matrix appliance=”pool-pump”]Pool pump cost across electricity rates
[hed_rate_matrix appliance=”pool-pump”]Pool pump running cost by state
Eight hours a day, every state. Pool ownership concentrates in warm states, which is fortunate given what the northeastern rates would do to these numbers.
[hed_state_costs appliance=”pool-pump”]Five ways to cut pool pump cost
Most pools do not need the runtime they get. The requirement is one full turnover of the water per day, and many pumps are sized to do that in four hours while being scheduled for eight or twelve out of habit.
- Work out your actual turnover. Pool volume in gallons divided by pump flow in gallons per hour gives the hours needed. Anything beyond that is optional.
- Reduce runtime in steps. Cut an hour, watch the water for a week, cut another. Cloudy water tells you when you have gone too far.
- Run during off-peak hours. Pool pumps are the ideal time-of-use load because nobody cares when they run.
- Keep the skimmer and pump baskets clear. A restricted intake makes the motor work against pressure it should not be seeing.
- Consider a variable-speed replacement. At current rates the energy saving on a heavily used pool often pays back the pump within two seasons, which is unusually fast for an equipment upgrade.
How this compares to everything else you plug in
Per hour of runtime against the other outdoor and utility loads.
[hed_compare_table appliances=”pool-pump,hot-tub,well-pump,sump-pump,central-air-conditioner,electric-water-heater”]Questions people actually ask
[hed_faq]How much does it cost to run a pool pump per month?About [hed_cost appliance=”pool-pump” period=”month”] for a 1,500 W single-speed pump running eight hours a day at the US average rate. A variable-speed pump doing the same job typically costs a quarter of that.
How many watts does a pool pump use?Single-speed pumps commonly draw 750 to 2,500 W depending on horsepower, with 1,500 W typical for a 1.5 hp residential unit. Variable-speed pumps at low speed can run under 200 W.
How many hours a day should a pool pump run?Long enough for one full turnover of the pool volume, which for many residential setups is four to six hours rather than the eight to twelve often scheduled. Reduce gradually and let water clarity tell you where the limit is.
Is a variable speed pool pump worth it?For a pool run through a full season, usually yes. Power rises with the cube of flow rate, so running slower for longer moves the same water for roughly a quarter of the energy. Payback is often two seasons or less at current rates.
Is it cheaper to run a pool pump at night?Only on a time-of-use tariff, where it is one of the easiest loads to shift. On a flat rate the timing makes no difference to cost, though running during daylight helps chlorine effectiveness.
Does a pool heater cost more than the pump?An electric resistance pool heater costs far more per hour, but is usually run for shorter periods. Over a season a single-speed pump running daily often still totals more than intermittent heating.[/hed_faq]
Related running costs
[hed_related appliances=”hot-tub,well-pump,sump-pump,central-air-conditioner”]Running it on solar
A pool pump uses [hed_daily_energy appliance=”pool-pump”] a day, which needs about [hed_panels_needed appliance=”pool-pump”] standard 400 W panels. Full array, battery and inverter sizing is on how many solar panels to run a pool pump.