When To Run Pool Pump If You Have Solar Panels?

What's The Best Time To Run Pool Pump With Solar Panels?

Solar panels are increasing in popularity. Whether your entire home is solar-powered or you just have a small solar system for outdoor use, you may be wondering: when is the best time to run a pool pump with solar panels?

In this article we will discuss the best time of day to run your pump in terms of water chemistry and saving electricity, and we also give a final recommendation in terms of when to run your pool’s pump if it is powered by solar panels.

Best Time Of Day To Run Your Pump: Water Chemistry

Most pool owners run their pool’s pump and filter system during the daylight hours, which is perfectly fine.

You may occasionally come across sources on the internet that suggest your chlorine deteriorates more rapidly during the daylight and to therefore avoid running your pump during this time, but this advice is slightly flawed.

To begin with, all outdoor pools should have an ideal concentration of cyanuric acid, sometimes called pool stabiliser.

Cyanuric acid acts as a ‘sunblock’ for your pool’s free chlorine molecules, preventing them from deteriorating in the sun during daylight hours. To read more about how cyanuric acid protects your pool’s sanitizer, check out our ultimate guide to cyanuric acid.

Running your pump has little to no effect on the rate at which chlorine is used up in your pool, unless your pump’s water outlet creates a great deal of water agitation.

This condition involving water agitation is undesirable overall and is meant to be avoided for a host of other reasons.

Best Time Of Day To Run Your Pump: Saving Electricity

The best time of day to run your pump in order to save on your electricity bills is typically at night.

In many areas of the country, you are charged a different rate per kilowatt hour for electrical usage during ‘peak usage hours’ of the day, which tend to be the busiest and hottest part of the day, from approximately 9am-5pm.

Although your electricity bills may be cheaper if you only run your pool pump at night, this is not recommended unless absolutely necessary.

During the day, your pool water absorbs heat from the sun. Without the pump running during this heating period, you are likely to develop cold and warm pockets of water.

Stagnant areas of water that have a warmer than average temperature are at an increased risk of allowing bacterial growth to develop. For this reason, running your pump while your pool is being heated by the sun is recommended so that your pool can maintain more uniform water conditions.

Overall Best Time To Run Pool Pump With Solar Panels

If you power your pool pump with solar panels, the best time of day to run your pool’s pump is during hours of maximum daylight.

This is typically between 8am-4pm, but may vary slightly depending on the season you are experiencing, whether daylight savings time is active, and your distance from the equator.


Solar panels are able to produce energy during the heat of the day, but they can struggle to retain this energy after sundown.

Therefore, it is best to run your solar-powered pool pump during normal daylight hours. This is the best solution for your pool’s chemistry, your solar power system, and water sanitisation.

Do you have any questions about when to run your solar-powered pool pump? Get in touch with us in the comments, we’d love to help!

Louis from Pool Advisor


A chemical engineer by trade, Louis is committed to debunking myths in the pool industry by explaining the underlying chemistry and making it accessible to all.