What Is A Solar Pool Heater?
A Solar Pool Heating system involves pumping pool water through a series of tubes, known as a Solar Collector or Solar Absorber mounted on the ground or roof of a building. The sun’s free energy heats the circulating water, returning it back to the pool at an elevated temperature.
Solar pool heating systems work seamlessly with your pool equipment and are fully automatic. You set the desired water temperature on the solar control. And when solar energy is available on the solar collectors.
An automatic motorized valve directs the water through the solar panels and directs the solar heat back to the pool. This process continues until either the pool’s filter pump is switched off for the day or the desired pool temperature has been reached. For more detail read – How does solar energy work?
In most cases, the existing filter pump can easily deliver sufficient flow to the solar panels. The only requirement is that the filter pump must be operated during the day (10:00 am to 5:00 pm).
This is the time most pool professionals would recommend running your filter, whether you have solar or not. It is also the time when the pool is most likely to be used and the time when good circulation is required for sanitizing chemical distribution.
How Does Solar Pool Heater Work?
Most solar pool heating systems include the following:
- A solar collector — the device through which pool water is circulated to be heated by the sun An illustration of a solar panel. A tube is at each end of the panel, and arrows show the flow going through one tube, across the panel, and out the end of the other tube, which is labeled the header/manifold.
- 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 — an automatic or manual device that diverts pool water through the solar collector.
Pool water is pumped through the filter and then through the solar collector(s) where it is heated before being returned to the pool. In hot climates, the panels can also be used to cool the pool during the peak summer months by circulating the water through the panels at night.
Some systems include sensors and an automatic or manual valve to direct water through the collector(s) when the collector temperature is sufficiently higher than the pool temperature. When the collector temperature is similar to the pool temperature, the filtered water simply bypasses the collector(s) and is returned to the pool.
Solar pool collectors for swimming pools are made of different materials. Which type you need depends on your climate and how you intend to use the collector. If you only use your pool when the temperature is above freezing, you probably only need an unglazed collector system. Unglazed collectors do not contain a glass cover (glazing).
They are generally made of durable rubber or plastic that has been treated with a UV light inhibitor to extend the life of the panels. Unglazed collectors are usually less expensive than glazed collectors due to their inexpensive parts and simple design.
These unglazed systems can even be used for indoor pools in cold climates if the system is designed to drain back into the pool when not in use. Even if you need to shut down the system in cold weather, unglazed collectors can be more cost-effective than installing a more expensive glazed collector system.
Example of how a solar collector works.
Glazed collector systems generally consist of copper tubing on an aluminum panel with an iron-tempered glass cover, increasing their cost. In colder weather, glazed collector systems—with heat exchangers and transfer fluids—capture solar heat more efficiently than unglazed systems.
Therefore, they can be used all year round in many climates. Glazed collectors can also be used all year round for heating water.
Both glazed and unglazed collector systems must include freeze protection when used in colder conditions.
How Much Does It Cost to Install a Solar Pool Heater?
A solar pool heating system usually costs between $2,500 and $4,000 to buy and install. This provides a payback of between 1 and 7 years, depending on your local fuel costs and available solar resource. They also typically last longer than gas and heat pump pool heaters. Your actual cost and payback depend on many factors.
- The national average cost of installing a solar pool heater averages between $3,000 and $7,000, with most people paying $5,000 for a glazed solar panel pool heater for a 12-foot x 24-foot in-ground pool.
- On the lower end of the spectrum, unglazed solar panels can cost as much as $2,000 for a 10-foot x 20-foot in-ground pool mounted on a platform near the pool.
- On the high end, you might pay $10,000 or more for a high-temperature home-mounted collector for a large 18-foot by 36-foot pool.
Solar Pool Heater Installation Cost
|National average cost||$5,000|
Solar Pool Heater Costs by Type
A solar pool heater costs between $500 and $11,000, depending on the type. All solar pool heaters work similarly but are made of different materials and come in different sizes. There are four types of solar pool heaters. Some types work better than others in certain pools depending on the type of pool and material.
|Type||Average Cost (Installed)|
|Propylene Mats||$500 – $3,000|
|Unglazed Solar Panels||$1,500 – $4,000|
|Glazed Solar Panels||$3,000 – $8,500|
|High-Temperature Collectors||$9,000 – $11,000|
1. Propylene Mats
Propylene mats are the most cost-effective system. The mats range from $500 for a small pool to $3,000 for a larger pool. Sometimes called unglazed solar heating, it is made up of a mat of fabric with coils running through it.
In warm, sunny climates such as California or Florida, the mat is a good choice. However, it is less effective at heating pools in temperate climates.
2. Unglazed Solar Panels
Unglazed solar panels are simpler and cheaper than glazed solar modules. These panels are made of plastic or heavy-duty rubber mixed with UV light inhibitors to extend the life of the panel. They just don’t have the same glazing or exterior glass cladding.
Unglazed solar panels behave the same way as glazed solar panels in the warm months, but the glass cover allows glazed solar panels to perform better in the cold months. Expect between $ 1,500 and $ 4,000 for these panels.
3. Glazed Solar Pool Heater
Glazed solar panels cost between $3,000 for a small system and $8,500 for a large system. When you think of solar panels, you usually think of a glazed system made of glass. This system is better suited for areas where more heat is needed or where there are not enough long, sunny days to generate enough solar heat.
Glazed solar pool heaters are made of copper pipes attached to an aluminum plate and covered with iron-hardened glass. The design is more efficient at capturing solar heat in cold weather areas than unglazed systems. A glazed solar pool heater can be used all year round.
4. High-Temperature Solar Collectors
Solar collector collectors cost between $9,000 and $11,000, depending on their size and type. If you live in an area where there is not much sun, you can still use solar pool heating. However, you will likely need a system called a high-temperature collector that uses mirrors to increase the amount of sunlight that heats the water.
These collectors are designed to significantly increase the heat of the water. This is a great benefit in colder areas or in places that don’t get a lot of sunlight.
Solar Pool Heater Cost by Pump Size
Solar pool heater pumps range from $50 to $1,300, depending on the size or style. Some solar pool heaters require a pump to effectively circulate the warm water with the cooler water. This pump can be operated with solar panels or with electricity.
|Pump Size||Gallons per Minute||Pump Cost (Materials Only)|
|0.5 HP||40||$50 – $400|
|1 HP||60||$150 – $600|
|1.5 HP||68||$200 – $700|
|2 HP||76||$500 – $750|
|2.5 HP||80||$600 – $800|
|3 HP||85||$700 – $1,300|
Solar Pool Heater Prices by Collector Size
Pool Heater costs between $ 2,800 and $ 8,000, depending on size and performance. Solar panels vary in size, but many are 4 “x 10” or 4 “x 20”. The number of panels needed in a system depends on many factors including the size of the pool, your climate, whether it is an in-ground pool or an above-ground pool, and whether you are using a pool cover.
|Number of 4’ x 10’ Solar Panels||Pool Surface Area||Cost (Materials Only)|
|4||288 sq.ft.||$2,500 – $4,500|
|6||512 sq.ft.||$3,100 – $5,200|
|8||648 sq.ft.||$5,000 – $7,200|
|10||800 sq.ft.||$6,100 – $8,000|
The Cons of Solar Pool Heaters
There are factors beyond cost that may render a solar pool heater the wrong choice for your home…
- Time Intensive. Solar pool heaters can take a long time to heat up your pool. However, the exact time depends heavily on the pool size and the outside temperature. These heaters probably aren’t for you if you’re looking for quick heating options. Solar pool heaters can take a full day to warm your pool by 5-7 degrees even in constant sunshine.
- Requires sunshine. The catch with solar pool heaters is that they need bright sunny days to work. But the temperature on these days is high enough that you may not need a heated pool. Warm water is a blessing on days when the sun isn’t shining and it’s cold outside. However, without steady sunlight, solar pool heaters cannot transfer thermal energy to your pool water.
- Solar pump. Your pool water will not be heated for free without a solar pump. They need electricity to pump the water to the solar panels. This can add to your energy bills. But as we said earlier, the increase in utilities is minimal, especially when compared to other pool heaters options.
Solar Pool Heater Advantages
Solar pool heaters come with a variety of pros that offset the disadvantages by a large margin. Here are some of the more obvious ones:
- Easy maintenance. A solar pool heating system consists of only a few parts. Therefore, little to no maintenance is required over many years.
- Adequate heating. If you live in a place with lots of sunlight, solar pool heaters will have no problem raising the temperature of your pool. And when you pair the heating with a solar pool cover, you are in good shape to take a warm bath at any time.
- Use automatic switching valves. With a little extra investment, you can get an automatic diverter valve that will automatically sense the pool temperature and divert water to the solar panels. This means that the system can be automated to keep your pool constant within a certain temperature range.