Gas Pool Heater vs. Heat Pump vs. Solar Pool Heating: What’s Best for your Pool?

Gas vs. Heat Pump vs. Solar: What’s the Difference?

If you want warmer pool water or a longer swimming season, choosing the right way to heat your pool can make a big difference in both comfort and operating costs.

Across the United States, homeowners generally have three main pool heating options to consider: a gas pool heater, an electric heat pump, or solar pool heating.

When comparing gas vs heat pump vs solar for your swimming pool, The best choice depends on where you live, how you use your pool, how quickly you need it heated, your desired water temperature, and how much you want to spend operating the system.

For many homeowners, solar pool heating deserves to be part of that comparison, especially when the goal is extending the swimming season without adding significant ongoing heating costs.

Comparing the Three Main Pool Heating Options

Before deciding which system is best, it helps to understand how each one produces heat.

Gas Pool Heater

A gas pool heater burns natural gas or propane to create heat. Pool water passes through the heater, absorbs that heat, and returns to the swimming pool.

Gas heaters can raise pool temperatures relatively quickly and can continue producing heat even when outdoor temperatures are low.

Pool Heat Pump

A pool heat pump uses electricity to capture heat from the surrounding air and transfer it into the pool water.

Instead of generating heat through combustion, the system moves available heat from the air into the pool.

Heat pumps generally heat a pool more gradually than gas heaters and tend to perform most efficiently when outdoor temperatures are warmer.

Solar Pool Heating

A solar pool heating system uses the sun as its heat source.

Pool water is circulated through solar collectors, typically installed on a roof, ground-mounted rack, or other suitable structure. Solar energy warms the water as it passes through the collectors before returning it to the swimming pool.

The major difference is what happens after installation.

Gas heaters require fuel whenever they operate. Heat pumps require electricity.

A properly designed solar pool heating system uses available solar energy and primarily relies on the pool's existing circulation system to move water through the collectors.

That can make solar especially attractive for homeowners who want to extend their swimming season while keeping ongoing heating costs low.

When Does a Gas Pool Heater Make Sense?

Gas heaters have one major advantage:

Speed.

If your pool is normally left unheated and you want to quickly raise the temperature before a party, holiday weekend, vacation, or special event, gas can be an excellent solution.

Gas is also useful when dependable heating is required regardless of sunshine or outdoor air temperature.

That can be particularly important in cooler parts of the United States or for homeowners who occasionally want to swim during colder weather.

The trade-off is operating cost.

Every time a gas heater runs, it consumes natural gas or propane. Maintaining a large swimming pool at an elevated temperature for extended periods can therefore become expensive.

Gas heaters tend to make the most sense when rapid, on-demand heating is more important than minimizing operating costs.

When Does a Pool Heat Pump Make Sense?

Heat pumps are another popular choice for residential swimming pools.

Rather than creating heat directly, a heat pump extracts available warmth from the outside air and transfers it into the pool.

Heat pumps are generally better suited to maintaining a desired temperature over time than rapidly heating a cold swimming pool.

They can be an excellent option for homeowners who swim frequently and want predictable temperature control.

Climate matters, however.

Because heat pumps extract heat from the surrounding air, their performance and efficiency can change as outdoor temperatures fall.

This means a heat pump operating in South Florida, Southern California, Arizona, or Texas may experience very different conditions than one operating during spring or fall in New York, Pennsylvania, Michigan, Massachusetts, or other northern states.

A heat pump also requires electricity whenever it operates.

For homeowners comparing long-term operating costs, this is where solar pool heating becomes particularly interesting.

Why Solar Pool Heating Makes Sense Across the United States

Solar pool heating isn't limited to hot climates.

In fact, homeowners in cooler regions can have an especially compelling reason to consider solar:

Their natural swimming season is shorter.

A homeowner in Florida may want warmer water during winter and spring.

A homeowner in New York, New Jersey, Pennsylvania, Connecticut, Massachusetts, Michigan, Ohio, or another northern state may simply want to start swimming earlier in spring and continue swimming later into fall.

Homeowners in California, Arizona, Nevada, Texas, Georgia, the Carolinas, and other sunny regions may have an even longer period when useful solar energy is available.

The goal is the same:

Use available sunshine to put additional heat into the swimming pool.

During normal operation, pool water is diverted through solar collectors. The collectors absorb solar energy and transfer that heat directly into the water before it returns to the pool.

There is no combustion process and no compressor generating the heat.

Once the system is installed, the sun provides the energy used to heat the water.

How Much Warmer Can Solar Make a Pool?

A properly sized solar pool heating system can make a significant difference in pool temperature and swimming season.

However, there isn't one temperature increase that can be promised for every pool in every part of the country.

Performance depends on several factors, including:

• Geographic location

• Pool surface area

• Available collector area

• Roof direction and orientation

• Amount of direct sunlight

• Collector size

• Wind exposure

• Shade around the pool

• Desired swimming season

• Use of a pool cover

• Daily weather conditions

  
  

This is why solar pool heating systems should be properly sized for the individual pool and location rather than simply installing however many panels happen to fit conveniently.

A solar system designed for a pool in Miami will have different seasonal expectations than one designed for a pool in New York.

If you're unsure how much collector area your pool needs, you can request a free custom solar pool heater design based on your actual pool, property, location, and swimming goals.

Solar Pool Heating Is About Extending Your Swimming Season

One of the most important things to understand about solar pool heating is what it is designed to accomplish.

Solar isn't necessarily intended to duplicate everything a gas heater can do.

If it's a cold night and you want an 85°F swimming pool tomorrow morning regardless of weather conditions, gas will generally be the better tool for that particular job.

Solar is better suited to homeowners asking a different question:

How can I comfortably use my pool for more months of the year without spending a fortune heating it?

In northern states, that could mean opening the swimming season earlier in spring and extending it further into fall.

In southern states, it could mean maintaining more comfortable water temperatures through portions of winter, spring, and fall.

In either situation, solar captures heat that would otherwise be unused and transfers it directly into the swimming pool.

Solar Pool Heating in Northern States

Solar can be particularly interesting in areas where homeowners have invested tens of thousands of dollars in a swimming pool but only get a few comfortable swimming months each year.

States such as New York, New Jersey, Pennsylvania, Connecticut, Massachusetts, Ohio, Michigan, Illinois, and others experience shorter natural swimming seasons.

That doesn't mean solar pool heating cannot work there.

It means the system needs to be designed around the local climate and the homeowner's expectations.

The objective may be less about year-round swimming and more about gaining valuable additional weeks or months at the beginning and end of the normal pool season.

For many homeowners, extending a four-month swimming season is extremely valuable.

Solar Pool Heating in Southern States

In warmer regions, solar pool heating can potentially provide an even longer useful heating season.

Florida, Texas, Southern California, Arizona, Georgia, the Carolinas, and other southern markets often experience extended periods of useful solar conditions.

Pools can still become uncomfortable even when daytime air temperatures seem warm.

Cool nights, evaporation, wind, shade, and seasonal temperature changes continually remove heat from swimming pools.

Solar can help replace some of that lost heat using energy from the sun.

What About Solar vs. a Heat Pump?

For many homeowners, this is the most interesting comparison.

Both systems can be used regularly throughout the swimming season, but their operating economics are very different.

A heat pump uses electricity whenever it is actively heating the pool.

Solar uses available sunshine as its heat source.

If you want precise temperature control and the ability to generate heat when solar conditions aren't favorable, a heat pump has an advantage.

If your priority is extending the swimming season while minimizing ongoing heating costs, solar can have a major advantage.

But there is another option homeowners sometimes overlook.

You don't necessarily have to choose only one.

Can You Use Solar Pool Heating With a Heat Pump or Gas Heater?

Yes.

Solar pool heating can work alongside an existing gas heater or heat pump.

In a hybrid setup, solar can become the primary source of heat whenever adequate solar energy is available.

The gas heater or heat pump can then provide supplemental heating when necessary.

This approach can be particularly useful for homeowners who already own a conventional pool heater.

Instead of removing perfectly functional equipment, adding solar may reduce how frequently the conventional heater needs to operate while preserving the ability to heat the pool when solar conditions aren't sufficient.

You get the benefit of solar energy when it's available while keeping backup heating for times when you need it.

For some homeowners, this can provide the best combination of low operating costs and dependable temperature control.

Your Location Matters

Location is one of the most important considerations when designing a solar pool heating system.

Solar availability, outdoor temperatures, nighttime temperatures, wind, humidity, and the length of the natural swimming season vary tremendously across the United States.

That's why solar pool heating shouldn't be sold as a one-size-fits-all package.

The question isn't simply:

“Does solar pool heating work in my state?”

A better question is:

“How should a solar pool heating system be designed for my pool, property, location, and swimming goals?”

That's the question a proper system design should answer.

Your Roof and Property Matter Too

The available installation area is another major consideration.

Solar collectors are commonly installed on roofs, but the roof isn't the only option.

Depending on the property, collectors can potentially be installed on:

• House roofs

• Detached garages

• Pool houses

• Pergolas

• Ground-mounted racks

• Other properly designed structures

  
  

Roof direction matters because different orientations receive different amounts of useful solar energy throughout the day.

South-facing installations are generally excellent, but southeast, southwest, east, and west-facing roofs can also work depending on the location, available collector area, shade, and desired performance.

Shade is another major consideration.

Trees, neighboring buildings, roof obstructions, and other sources of shade can reduce the amount of solar energy reaching the collectors.

A shaded swimming pool may also require additional heating because it receives less direct solar gain.

All of these factors should be considered when sizing the system.

Pool Size Alone Doesn't Determine Solar System Size

One of the biggest mistakes homeowners can make is assuming solar pool heating is sized only according to pool gallons.

Pool surface area is extremely important because that's where much of the heat is lost.

Two pools containing similar amounts of water can have very different heating requirements depending on their:

• Shape

• Surface area

• Geographic location

• Shade

• Wind exposure

• Collector orientation

• Available sunlight

• Desired swimming season

  
  

Collector orientation matters as well.

A less favorable roof direction may require additional collector area to compensate for reduced solar exposure.

That's why a custom solar pool heating design is valuable before purchasing equipment.

Don't Forget About Heat Loss

Generating heat is only half of the equation.

Keeping that heat in the swimming pool matters just as much.

Evaporation is one of the largest sources of pool heat loss.

Wind and cool nighttime temperatures can remove a substantial amount of heat accumulated during the day.

Using a pool cover can dramatically reduce evaporation and help preserve heat already stored in the water.

This benefits gas heaters, heat pumps, and solar pool heating systems alike.

For solar pool heating, reducing overnight heat loss can make the solar energy collected during the day even more valuable.

Solar Can Even Help Cool an Overheated Pool

Here's something many pool owners don't realize:

Solar pool collectors can potentially be used to help cool an overheated swimming pool.

In hotter regions of the United States, some pools become warmer than homeowners actually want during summer.

Under suitable conditions, pool water can be circulated through the solar collectors at night when the outdoor air and collectors are cooler than the swimming pool.

Instead of collecting solar heat, the system works in reverse and allows heat from the pool water to dissipate through the collectors.

That means the same solar system used to extend your swimming season during cooler weather can potentially help manage excessive pool temperatures during hot summer conditions.

Which Pool Heating Option Is Best for You?

There isn't one heating system that's best for every swimming pool.

Choose gas if rapid heating, on-demand operation, and dependable cold-weather performance are your biggest priorities.

Choose a heat pump if you want controlled, consistent heating and are comfortable with the electricity required to operate it.

Consider solar pool heating if your primary goal is extending your swimming season while using available sunshine and minimizing ongoing heating costs.

And if you already have a gas heater or heat pump, consider using solar as your primary heating source whenever conditions allow while keeping your existing heater as supplemental backup.

The best choice depends on your climate, pool, property, budget, swimming habits, and expectations.

Find Out How Much Solar Pool Heating Your Pool Needs

The performance of a solar pool heating system depends heavily on getting the design right.

At DIYSolarPoolHeaterKits.com, we've helped thousands of homeowners with solar pool heating systems and can design a system specifically around your pool and property.

We'll consider your:

• Pool size

• Geographic location

• Available installation area

• Roof direction

• Shade

• Desired swimming season

• Other important site conditions

  
  

From there, we can determine the recommended collector area and system configuration.

Whether you're planning to install the system yourself, have a family member or friend help, or need assistance finding an installer in your area, we can help you determine the right setup before purchasing your equipment.

Request your free custom solar pool heater design and find out what solar can do for your pool.