As refreshing as it feels to take a cool dip in the pool on a hot summer day, that cool dip isn’t going to feel quite as comfortable in, say, November. That’s why people around the world are adding solar pool heater systems to their swimming pools, in order to enjoy warmer water temperatures throughout the year. Solar pool heaters help homeowners reduce ongoing the costs of heating their pools and enjoy the benefit of low operational costs. This type of swimming pool heater is also competitive in cost compared to gas heaters and heat pumps.
How Do Solar Pool Heaters Work?
Solar pool heaters are simple in theory—especially since most of the original pool equipment is relied upon to make the system work properly. Solar pool heating systems work by use a few basic components:
Pool filter: A water filtering system that is already part of most swimming pools that is designed to remove debris from the pool water.
Solar collector: This device heats pool water using solar energy. Pool water enters the solar collector after leaving the pool filter.
Pump: This is the part of the system that circulates water to appropriate area. It moves the pool water through both the filter and collector, before directing it back to the pool.
Control valve: This valve allows homeowners to control the system and where the water is flowing. They come in both automatic and manual versions. The homeowner uses the control valve to utilize the solar collector and heat the pool when needed, or “turn off” the solar pool heater when it is not needed.
Most swimming pools have filters, as well as pumps and plumbing systems, no matter whether they have a heating system or not. A solar pool heater simply adds one additional path for that waterflow framework to follow. Instead of looping right back to the pool after entering the filter, the water also enters a solar collector before returning to the pool. Inside the solar collector, heat from the sun warms the water before it makes it back to the pool once again.
Enough loops through this cycle will warm up the water of the pool over time. The size of the solar water heating system, the size of the pool, and the amount of sunlight all help determine how much the system can heat the pool in reality.
How Much Do Solar Pool Heaters Cost?
One significant benefit to using a solar water heater for pools is that they are similar in cost to other types of pool heaters, such as gas heaters and heat pumps. But they offer the added benefit of saving money over time when it comes to utility costs related to heating the swimming pool.
The first cost to consider when it comes to a solar pool heater system is installation, or upfront costs. On average, the cost to install a solar pool heater is between $3,000 and $5,000. Some homeowners will pay as much as $7,000, depending on the size of the solar water heating system required for their home and the type of solar panels used. The typical time it takes to earn back the investment is between 1.5 and 7 years.
Homeowners can choose between glazed solar panels and propylene mats for their solar water heater. Glazed panels tend to be slightly more expensive, but result in less energy loss – which means your pool heats up quicker.
Keep in mind that gas pool heaters tend to be less expensive upfront, compared to solar pool heaters – but not by much. Gas pool heater installations typically cost between $1,500 and $6,000. However, they are less energy-efficient, so they can result in higher utility bills over time. For this reason, solar pool heaters typically offer a larger return on investment.
Type of Pool Heater
Average Installation Cost
Solar pool heater
$3,000 – $5,000
Gas pool heater
$1,500 – $6,000
$2,000 – $6,500
Compared to other pool heating systems, solar pool heaters will reduce energy and utility costs related to heating a swimming pool. A solar pool heater costs $0-$10 monthly in utility costs to operate. Compare this to a gas pool heater, which typically costs $100-$400 monthly in operational costs.
Type of Pool Heater
Monthly utility cost
$0 – $10
$100 – $400
$120 – $200
Keep in mind that you will have to use electricity to use your pool’s pump. This is inevitable — but you will avoid the added cost of running a gas pool heater or heat pump.
Types of Solar Pool Heater Collectors
The solar collectors are the driving force behind solar pool heating systems. Without the solar collectors, there’s no heat source for the pool water. There are three major types of solar collectors used to heat swimming pools: flat-plate, bulk, and evacuated tube.
Flat Plate Solar Collectors for Pools
Many homeowners choose flat plate collectors because they are thin and therefore aesthetically pleasing, design-wise. They are also relatively simple to install and can be attached directly to your swimming pool line without worrying about heat exchangers. They provide plenty of heating power as long as there is direct sunlight, which is, of course, common throughout the normal swimming season. Flat plate solar collectors typically cost between $500 – $2,000, which is about half the price of an evacuated tube collector.
Bulk Solar Collectors for Pools
A bulk collector holds a large amount of water at one time to be heated by the sun. Because of the way bulk collectors work, they typically require a heat exchanger and a separate loop when heating pool water, but some people choose to tie them right into an existing pool line. The real benefit of a bulk collector is its simplicity and the fact that water can heat even when the pump isn’t cycling. While bulk collectors are the least efficient pool heating method, they cost an average of just $500.
Evacuated Solar Pool Heater Tube Collector
Evacuated tube collectors rely on vacuum tubes to generate and store heat, and they are the most efficient option available. They are also the most expensive, which is why some homeowners don’t want to make such a big investment simply to heat their swimming pool. Evacuated solar collectors for swimming pools can cost an upwards of $2,500+.
However, these collectors are the best option for those trying to heat water on cloudy days, and they stand up to wind effectively, as well.
No matter which type of solar collector you choose for your pool heater, it’s important that the array is sized appropriately to offer enough heat to make a difference for your particular swimming pool. Homeowners should work with a solar heating professional to help them determine what size system to use, as well as install the system.
Installing a Solar Water Heater for Your Pool
When it comes time to install the pool solar heater, it’s helpful to know what to expect. Typically, a solar professional will mount solar collectors to a nearby rooftop. If there is not a rooftop close enough by, one must be built to hold the collectors. Alternatively, the solar collectors can be ground mounted in a location free from many obstacles.
Once the professional mounts the solar collectors, they will set up all plumbing to make the system work. Pipes must “T-off” from the existing filtration loop in order to send water through the new solar water heater.
The installers will also install control valves, so you can control the water flow and turn on or turn off the solar water heater. Additionally, a vent is installed at the peak of the solar collector array, in order to keep water out of the collectors when the pump isn’t running.
Because of the complexity of the installation process, the large majority of homeowners will need to hire a solar professional to correctly and safely get the job done.
In-Ground vs Above-Ground Solar Pool Heaters
Although homeowners use heaters to warm the water temperature for both in-ground and above-ground pools, it’s much more common to invest in a solar water heater for an in-ground pool.
The major difference between heating different types of pools is the size of the heater required. Above-ground pools lose heat much faster than in-ground pools, so they require a more powerful water heater to efficiently keep the water warm. Homeowners can choose to invest in a solar heater for their above-ground pool, however, the investment may be larger than for in-ground pools.