Solar pool heaters: Overview and best products

Pool owners are fortunate to have a place to cool down during hot, sticky weather, but owning a pool is not without its pain points. To keep pools open for as long as possible, pool owners may spend a lot of money heating the water.

If you have a pool and are paying a lot to keep your pool temperature warm, you should consider renewable energy options for heating, such as "pool solar panels" (commonly known as solar pool heaters). While relying on warm weather to passively heat your pool is a good solution during the height of the summer, solar pool heaters are a great option to consider if you want to save money while extending the swimming season earlier into the spring and later into the fall.

Solar pool heaters use thermal energy from the sun to warm up your pool water. Similar to solar photovoltaic (PV) panels, solar energy collectors used to heat water in your pool are typically mounted on your roof. Water from your pool is pumped through a filter and up to the solar collectors on your roof. These solar collectors look similar to PV panels but include tubes throughout the inside so that cold water can circulate through the solar energy collector, absorb heat, and then return warm water to your pool.

The best part about solar pool heaters? You can save money on pool heating costs! Heating a pool with the sun's energy is environmentally friendly, and it helps save you money because you'll be relying on free power from the sun instead of purchasing the fuel you would otherwise use to heat your pool. The amount you'll save by transitioning to a solar pool heater will depend on the existing source of heat for your pool, the efficiency of your system, the upfront cost, and some other factors.

Solar pool heaters heat your pool water by pumping it through a filter and circulating it through tubes that transfer heat from solar energy collectors on your roof to the pool water. Many solar pool heaters also include flow control valves and automated sensors. These components detect the temperature of the water coming from the solar collectors compared to the desired temperature. If the pool water is cool and it's sunny out, the flow control valve diverts water through the solar collectors, which use the heating panels to warm the water before it's returned to your pool. Alternatively, if your pool is too hot, the control valves ensure that additional hot water doesn't flow into your pool and warm it up even more.

According to the Department of Energy, solar pool heaters typically cost between $2,500 to $4,000 to install on your roof. Your payback period for this investment depends on how much you would otherwise spend on fuel to heat your pool and how expensive energy costs are in your area. Most homeowners investing in solar pool heaters will break even on their investment in less than seven years.

The upfront investment of the system is the most significant cost associated with this technology – operating and maintenance costs can be as low as $0 in a year if you do not need to fix or replace any parts. Properly installed, high-quality solar pool heaters should operate efficiently for 10 to 20 years.

The size of your solar pool heating system will depend on several factors, including the size of your pool, the desired water temperature, and how much sunshine the collectors will receive (dependent on your geography, the tilt of the collectors, possible shading factors, etc.) You can install as many solar collectors as your roof can fit, but if your roof is covered in the shade for most of the day, the solar collectors won't meet your pool heating needs.

As a general rule of thumb, the surface area of your solar collector(s) should be 50 to 100 percent of the surface area of your pool. For example, a pool that is 200 square feet will need solar collectors with a minimum surface area of 100 square feet. If you live in a climate like Florida, where you're using your pool year-round, consider sizing the system on the higher end versus living in an area where you only swim for a few summer months.

Solar collector size estimates for typical home pool sizes

A qualified contractor offering solar pool heaters will be able to properly size your system, given the specifics of your pool and the location of the collector system. If you live in a climate with many cloudy days or experience some shading on your roof where the solar collectors might go, your contractor may suggest keeping an electric heater backup system in addition to the sun heater.

Most solar pool heaters you'll find online are just panels attached with a connector to your pool pump, which are easy enough to connect to your pool's existing pump. If you plan on installing your solar collectors on your roof, it's a good idea to consult a solar installation company or roofing professional to get the job done correctly and safely, so it will last a long time.

What solar pool heating products are available? Many companies sell solar pool heaters, so we've compiled a list of some of the popular options online for comparison:

Buyer's guide: Solar pool heaters

Fafco

Fafco offers multiple varieties of solar pool heaters suitable for above-ground pools. The Solar Bear system listed above is the most expensive of their three offerings, with two smaller options available depending on your pool size.

SmartPool

SmartPool's solar pool heating system is well-rated and affordable for an inground pool. However, this pool solar heater requires a separate installation kit.

Solar Pool Supply

Solar Pool Supply's DIY home solar pool heating system comes in various sizes to fit your needs and pool size. While it has the highest price point, it has a complete installation kit and a lifetime warranty.

You don't have to install an entire solar pool heater to benefit from solar power. Here are some other versatile solar-powered gadgets that you can use this summer:

Solar pool pumps

You can use solar energy to power the motor in your pool's pump, which is responsible for pushing water through a filter, cleaning it, and returning it to the pool. You can do this in several ways, including powering your existing electric pump with a solar PV system, purchasing and installing a DIY solar pool pump kit, or using a stand-alone solar pool pump that floats directly in your pool and requires no installation.

Buyer’s guide: Solar pool pumps

PWS

The PWS pump does not have solar panels but can attach to your home solar system. Offering three options depending on your pool size and needs, PWS provides a quick way to add solar energy to your pool.

ECO-WORTHY

Eco-Worthy's solar pool pump comes with its panels, allowing you to set it up without additional items or systems required (aside from a pool). They offer a range of sizes to fit different pool types.

Solar pool covers

If you're looking for a lower-cost solution to keep your pool at a comfortable temperature for swimming, one purchase you may want to make is a solar pool cover. Solar pool covers are more translucent than standard ones, allowing passive sun exposure to warm up your pool while helping out your pool's filtration system by keeping the water clear of debris. Covering your pool (with a solar cover or a traditional one) will also help trap the heat and prevent evaporation. The cost of solar pool covers depends upon the size you need to cover the surface area of your pool.

Buyer’s guide: Solar pool covers

Sun2Solar

Sun2Solar includes a range of sizes that fit inground or above-ground swimming pools at an affordable price point.

In the Swim

The In the Swim solar pool covers will trap heat in your pool while allowing additional sunlight to penetrate the cover and further warm your pool.

Blue Wave

Blue Wave solar pool blankets minimize heat loss and trap additional heat to keep your pool at a perfect water temperature for swimming.

Solar Sun Rings

Similar to solar pool covers, Solar Sun Rings float on the surface of your pool and absorb solar energy to heat the water below. These rings are also useful in preventing evaporation. One of the biggest differences between Solar Sun Rings and pool covers is the shape: Solar Sun Rings are smaller, and you'll likely need multiple of them to cover the surface of your pool. Because they are smaller, they're easier to remove and better suited for uniquely-shaped pools that may not have a perfect shape for a more standard solar pool cover.

Floating solar lights

If you're looking to light up your pool at night, consider solar floating lights as a solution. Many companies produce colored lights that will absorb solar energy during the day as they float on the pool's surface and then use that energy come nighttime to provide lighting.

Buyer’s guide: Floating solar lights

eLEDing

eLEDing offers colorful floating pool lights that sit on the surface of your pool. They soak up sunlight during the day to light up your pool for a night swim.

Intex

The Intex solar pool light is slightly more expensive, but that price accounts for the multiple light modes and auto on/off feature built into the light.

Solar energy is capable of much more than just heating your pool during the summer – you can harness the sun's rays to heat your entire home! The best place to compare options for home solar installations is the EnergySage Marketplace. By registering your property to get solar quotes, you can compare offers side by side from qualified, pre-vetted installers near you and speak with an Energy Advisor to discuss which offer is the best for you. If you're interested in also exploring your solar pool heating options, simply make a note in your account – many PV installers also install solar pool heaters (or can recommend a reputable company to do so).