If your pool pump runs mainly at night, it’s worth checking whether some of the filtration cycle can be moved to hours when solar power is available. For the change to be worthwhile, you need to know two things: how much surplus power is available during those hours, and what changes your pool equipment allows.
First, document how your pool operates
Ask your pool maintenance professional to show you the current schedule. Note the filtration hours, the pump speed during each cycle, and any equipment that depends on water circulation. Heating, chlorination, or cleaning may require a different flow rate from basic filtration. Record any second pump or heat pump separately so you know which device is using how much.
For an energy comparison, it’s best to record electricity use over one complete cycle. If there’s no separate meter, ask an electrician to recommend a suitable way to measure it. The power rating on the motor’s nameplate isn’t enough to calculate how much it uses at each setting.
Technical guide from Pacific Northwest National Laboratory on pump operation and water flow.
Compare the load with the actual surplus
Open your generation history and grid exchange readings for a few representative days when you use the pool. If the app shows exports, check how long they last and how much they vary. The day’s peak generation alone doesn’t show how much power will be available to the pump. Some of it may already be used by air conditioning, the kitchen, or battery charging.
Choose a practical schedule with your pool maintenance professional and compare the pump’s demand with exported power over the same period. If there are large fluctuations, consider using shorter measurement intervals. A high total generation figure for the day can coincide with grid imports while the pump is running.
Learn how to distinguish generation, exports, and imports.
An illustrative example
Suppose the pump draws a steady 0,8 kW for four hours and uses 3,2 kWh. With the evening schedule, and no generation or battery, all of this energy comes from the grid. For an alternative schedule, suppose that at least 0,8 kW is left over for three hours after other loads, and 0,3 kW for the fourth hour.
With these assumptions, the solar panels cover 2,7 kWh, and the grid supplies the remaining 0,5 kWh. The pump still uses 3,2 kWh. If the energy you would otherwise export has financial value to you, include that when estimating the benefit. These figures illustrate how to make the comparison and are not a recommended filtration duration.
Agree on which changes your installation allows
Ask your pool maintenance professional to identify which part of the cycle is flexible and which operations need to remain coordinated. Confirm the required water flow, filtration duration, and operating conditions for heating or chlorination. If the pump has variable speeds, consider the speed setting and schedule change separately. Each operation requires its own flow rate, which a technician can confirm for your specific pool.
If you’re considering an automation system that responds to surplus power, agree on how the cycle will be completed on cloudy days as well. Ask for compatibility with the pump controller and other equipment to be checked. For shared or commercial pools, the operations manager should assess any change separately.
Guide from Pentair on pump types and equipment that affects the required flow rate.
Check the results before making the change permanent- Keep the measurements from the original schedule and record the pool’s usage conditions.
- Try the agreed schedule on comparable days. Record the pump’s kWh, grid imports, and exports over the corresponding intervals.
- Check with your pool maintenance professional that the required cycles are completed and that water quality remains within the targets they have set.
If you’re planning a new solar installation, include the months when the pool is in use and the hours when its load can be shifted. At Solar Home, we use the property’s energy use and usage patterns for the assessment. You can send us the pump schedule and available readings so we can review them alongside your other needs. Contact Solar Home.
