Solar Swimming Pool Heating

Solar heaters are competitively priced compared to gas and heat pump alternatives, with minimal annual operating costs and, in certain climates, solar pool heating stands out as one of the most cost-efficient applications of solar energy.

Did You Know?

Heating a swimming pool can consume a significant amount of energy, resulting in high heating expenses?


Homeowners can enhance the heating efficiency of their pool by installing an energy-efficient pool heater, such as a solar heater, whilst implementing a variety of steps to lower pool heating expenses.

Solar Heaters

Solar heaters are competitively priced compared to gas and heat pump alternatives, with minimal annual operating costs and, in certain climates, solar pool heating stands out as one of the most cost-efficient applications of solar energy.

Most solar pool heating systems include the following elements:

  • A Solar Collector — the device through which pool water is circulated to be heated by the sun
  • A Filter — removes debris before water is pumped through the collector
  • A Pump — circulates water through the filter and collector and back to the pool
  • A Flow Control Valve — automatic or manual device that diverts pool water through the solar collector.
solar heating pool circulation process

The How:

Pool water is pumped through the pool filter and then through the solar collector(s), where it is heated before being returned to the pool.

In hot climates, the collector(s) can also be used to cool the pool during peak summer months by circulating the water through the collector(s) at night.

  • Some solar pool systems are equipped with sensors and a valve to redirect water through the collector(s) when the collector temperature exceeds the pool temperature.
  • If the collector temperature matches the pool temperature, the filtered water will bypass the collector(s) and return to the pool.


Solar pool collectors come in various materials, and the choice depends on climatic conditions and pool usage.

Sizing a Solar Swimming Pool Heater

Sizing a solar swimming pool heating system involves many factors:

  • Pool size
  • Length of swimming season
  • Average regional temperatures
  • Desired pool temperature
  • Site’s solar resource
  • Collector orientation and tilt
  • Collector efficiency


Tip: It’s important to understand the pivotal role a pool cover has on reducing your pool heating energy usage.


Did you Know?

  • Solar system contractors use worksheets and computer programs to help determine system requirements and collector sizing.
  • The surface area of your solar collector should equal 50%–100% of the surface area of your pool.
  • In cooler and cloudier areas, you may need to increase the ratio between the collector area and the pool surface area.
    • Adding collector square footage also lengthens the swimming season.

For example, a 15-by-30-foot outdoor swimming pool in Cairns (far north Queensland) typically requires a collector that equals 100% of the pool’s square footage to accommodate year-round use. This equals 450 square feet of collectors.

On Queensland’s Gold Coast, most people use outdoor pools 7-8 months per year, so they typically size their systems at 60%–70% of the pool’s surface area.

In any climate, you can usually decrease the required collector area by using a pool cover.

You’ll also want a properly sized pool pump for a solar system. If you’re replacing a conventional pool heating system with a solar system, you may need a pump larger than your current one or a separate, smaller pump to move the pool’s water to and through the collectors.

Selecting a Solar Pool Heater

A solar pool heating system typically ranges in cost from $2,500 to $4,000 for purchase and installation however, there are federal and state rebates available for rooftop solar and battery storage which can significantly reduce the cost of purchasing and installing a solar system.

For more information on government rebates please visit:


The actual cost and payback duration are influenced by various factors including local fuel costs and solar resources. Therefore, prior to acquiring and setting up a solar pool heating system, the following is recommended:

  • Evaluate your site’s solar resource
  • Determine the correct system size
  • Determine the correct orientation and tilt for the collector
  • Determine the system’s efficiency
  • Compare system costs
  • Investigate local codes, covenants, and regulations.

Installation and Maintenance

The successful setup of a solar pool heating system relies on various factors such as solar availability, climate conditions, local building codes, and safety considerations. For optimal results, it is recommended to engage a certified solar thermal systems contractor for the installation.

Following the installation, regular maintenance is crucial to ensure the system’s longevity of 10–20 years. Refer to your owner’s manual and consult with your contractor for maintenance guidelines. With routine checks on the pool’s chemical balance and filtration system, minimal maintenance should be needed for the collector. In arid regions, glazed collectors may require cleaning as rainwater might not provide a natural cleanse.

When screening potential contractors for installation and/or maintenance, ask the following questions:

  • Does your company have experience installing and maintaining solar pool heating systems?
    • Choose a company that has experience installing the type of system you want and servicing the applications you select.
  • How many years of experience does your company have with solar heating installation and maintenance?
    • The more experience the better. Request a list of past customers who can provide references.
  • Is the company licensed or certified?
    • Having a valid plumber’s and/or solar contractor’s license is required in most states. Contact your local council for more information.
    • Confirm licensing with your state’s contractor licensing board.
    • The licensing board can also tell you about any complaints against state-licensed contractors.