About Solar Power Pool Heaters

Solar power pool heaters are simple and silent solar collectors that convert the free energy from the sun into heat for pools and hot tubs. The system diverts water from the existing electric or gas heating system to a large, flat solar collector with full exposure to the sun. This type of system has the potential to pay for itself in a few years since it lowers heating costs.

This article may contain affiliate links. When you purchase through links on this site, I may earn a small commission at no extra cost to you.

Solar home heating is becoming more popular with residential homeowners, and so too are other forms of solar power. Passive solar heating systems have been used for ages to make bathing and swimming more fun. Modern systems use a pump to drive water through tubes in a solar collector to make the system more efficient and cost-effective. Most pools already have a circulation pump to filter the water. A solar collector can be added to warm the water before it returns to the pool.

How Does It Work?

Pools usually have a circulation pump that cycles the water through a filter, an electric or gas heater, and then back into the pool. A solar heater can be added beside the existing heater so that water will be diverted through the solar collector and then back into the pool.

Solar collectors - devices that store the sun's energy - differ in size and shape but all have a large, dark surface containing tubes to absorb solar heat. As the water passes through these tubes, it absorbs the solar radiation and the temperature of the water increases.

The water coming out of the solar power pool heaters typically increase in temperature by 1 to 2 degrees. The amount of heating depends on:

  • The size of the solar collector used (and amount of yard space to accommodate the panels).

  • The horsepower of the circulation pump and the flow rate of the water through the solar heater.

  • The amount of exposure to sunlight, which is dependent on location, climate and seasonal changes (where the sun is on the horizon).

Over the course of several days, the pool can gradually be heated to the temperature the pool owner desires.


  • The system can pay for itself in a few years by reducing electricity or gas bills.

  • Extends your swimming season by keeping the pool warmer just by using the sun's energy.

  • Reduces carbon emissions by using solar energy instead of polluting gas or coal-fired electricity generation.

  • Installation is relatively easy if you have enough yard space.

  • The system operates silently. Maintenance costs are very low.


Reduced heating costs are attractive, but these systems aren't for every pool owner. The first thing to consider is yard space and access to available sunlight. Solar collectors are large and flat and require full exposure to the hot afternoon sun. The circulation pump moves the water through the heating system and should do so when the most amount of free solar energy is available.

The size of the solar collector should be appropriately sized for your pool and your climate. If the system is too small, the time it takes for the system to pay for itself can be as long as 20 years! If the system is too large, then a larger circulation pump will be required to push the water through the extra plumbing. Again, the extra cost will take longer to recoup.

Solar collectors take up a lot of space. As such, the aesthetics are important - not just for the homeowner, but for the neighbors and the community as a whole. Solar collectors should be mounted at ground level, close to the pool. Roof mounting on a garage or home is possible but a more expensive two-speed circulation pump may be required. The higher speed is to pump the water vertically up to the roof while the slower speed is for the conventional heating system.

Solar power pool heaters are an option for pool owners who want to see noticeable savings on heating costs. However, just like with all solar energy systems, each owner must decide whether such a system is worth the cost and whether it will suit their lifestyle.