Solar pool heaters are the cheapest way to heat a Florida swimming pool

What Is The Cheapest Way To Heat My Pool?

In Education, Opinion 4 Comments

If you are looking for the cheapest way to heat your Florida pool, you have come to the right place. It’s a bit of a loaded question, but we will walk you through the options and relative costs of each major pool heating method.

For our analysis, we are going to assume similar quality levels for all technologies. For example, if we are talking about name brand units with premium heat exchangers, the same would apply to all technologies. In other words, we are making this as fair a competition as possible. Obviously, we have a bias toward solar, but the conclusions here are completely justified.

Gas Pool Heaters

At first glance, gas pool heaters are generally the cheapest initial installation cost for any pool heater. You can get a really good unit off-the-shelf for a low cost. They are simple devices that just burn fuel, along with some safety features and basic controls. However, if you do not have natural gas piped to your house or an existing liquid propane tank, you will have to get a buried tank in most cases. This drastically increases the initial cost, and it may no longer be the cheapest initial cost for you. It depends on your current situation.

That’s where the savings ends. Gas heaters are by far the most expensive heater to operate at current fuel prices. And not many people think that fuel prices are going to go down over the long term. It is very expensive to burn natural gas to heat a pool, and even more expensive to use liquid propane (LP).

Gas heaters generally do not last as long as electric heat pumps, and nowhere near as long as solar pool heaters. This is especially true if used frequently.

Electric Heat Pump Pool Heaters

Electric heat pumps come in all quality levels. For a quality unit that will last, it will be more slightly more expensive than a gas heater initially. If you do not have a suitable electric circuit at your pool equipment pad already, a licensed electrician will need to run a new circuit. Electric heaters typically require a 40 amp or 50 amp circuit, so your existing electrical may not be sufficient, even if you already have an electrical subpanel near your pump. The cost of running a new circuit may skew an electric heater initial cost upward drastically.

While the operating cost of an electric heat pump pool heater is lower than gas, performance and efficiency depend on the ambient conditions. Lower temperatures and lower humidity reduce the efficiency of heat pumps. In fact, if it gets too cool out a heat pump may not heat your pool at all, but continue running, costing you dearly. Heat pumps are generally rated at a water temperature of 80°F, air temperature of 80°F, and 80% relative humidity. Anything less and you can throw the efficiency figures out the door.

Think about it – what are the conditions when you need to heat your Florida pool the most during the spring and fall? It’s when the outside temperatures are in the 60’s and 70’s, your pool is in the low to mid 70’s, and the relative humidity dips into the 50’s each afternoon.

About half of the installations we do are for clients that already have an electric heat pump and got stung by a high bill. They are shocked to find out that while heat pumps work efficiently in ideal conditions, they are wildly inefficient when you need them the most. Still, on average electric pool heaters are cheaper to operate than gas heaters, all else being equal.

Heat pumps last at least as long as gas heaters, but about half as long as a solar pool heater.

Solar Pool Heaters

Solar pool heaters can by the same price or slightly more than an electric heat pump. In some cases, solar pool heaters can be more expensive due to long plumbing runs or additional performance and convenience features selected by the homeowner. For example, if there is no existing pool automation system (controller), solar dealers typically recommend a differential solar controller. These maximize performance, increase convenience, and integrate into existing or future variable speed pool pumps.

So solar pool heaters are rarely the cheapest up front. But you can probably guess the real story. There is essentially ZERO cost to operate a solar pool heater. Once you make your initial investment you are finished.

In its lifetime, you can easily spend more money on gas or electricity than a gas or electric heat pump costs initially!

When it comes to lifetime cost, a solar pool heater is the clear winner when it comes to the cheapest pool heater. The small additional upfront cost is nothing compared to the lifetime savings. Aside from that, you can leave your solar pool heater on all the time. This adds massive convenience and increases enjoyment dramatically in our experience.

Maintenance and Longevity

Like all appliances and mechanical devices, at some point, there will be a service issue. A technician will have to come out to fix a problem or let you know if your pool heater has reached the end of its useful life. In this analysis, we are ignoring these costs because they are unknown and there is no typical answer. There is always a chance that a mechanical device will fail to perform properly. If you purchase a quality product, you are less likely to experience issues.

But we do know about longevity. Solar pool heaters generally last about twice as long as heat pumps and three times as long as gas heaters. This is borne out in the warranties that manufacturers provide. Gas heaters are generally warranted from 1-5 years*. Electric heat pumps have 1-7 year warranties*. Most solar pool heater manufacturers offer a 10 or 12-year warranty! There is clear confidence in the longevity of solar pool heating panels. With no moving parts, there is nothing to mechanically break down. Solar pool heaters reach end-of-life when leaks become prevalent due to untraviolet breakdown of the solar collector or physical damage due to wind action, expansion and contraction, or other physical actions like strikes or abrasion.

That means you need to consider that you will likely have to purchase two electric heat pumps or three gas heaters in the life of a solar pool heater.

* We should note that gas and electric heaters may have 10-year heat exchanger warranties, but these are not usually the components that cause those heaters to reach end-of-life.



When you consider lifetime operating costs and longevity of solar pool heaters, they are definitely the cheapest pool heating solution in Florida. No other technology comes close. In the lifetime of a solar pool heater, you will get way more total heating because you would never run your gas or electric heater every day (unless you have very deep pockets). Solar pool heaters can be left on all the time (until the water gets too warm for your comfort!)

While gas and electric heaters can reach higher ultimate temperatures at times, solar pool heating is the right balance of cost and pool enjoyment for the vast majority of Florida pool owners. There is a good reason that so many people with existing gas and electric heaters come to us to add solar panels to their pool. The cost of heating your pool any other way is usually prohibitive, if not painful.

In our estimation, over the last four decades, there have been over 100,000 solar pool heaters installed in Southwest Florida. Nothing has changed. Solar pool heating is still the cheapest, most affordable way to heat your Florida swimming pool.



  1. My husband does not want to put anything on our roof and is always pointing out to me that people don’t put the solar back up when their roofs are replaced. How do I convince him that solar is the way to go? I showed him this website but he is not budging on putting solar panels on our roof. I want solar, can you help me convince him?

    1. Author

      In the last three years, we have replaced literally hundreds of solar pool heaters, so the conclusion that people don’t put them back up is not accurate. The methods and materials we use today to protect roofs is light years ahead of the old fashioned way. Our competitors haven’t quite caught up, and I don’t know why. The flashings and elevated pipe pads we use have changed the game. I would need to know the specific reason for hesitation. If you had a bad experience, I’m sure the issue has been mitigated with modern materials and methods. We’re here to help!

  2. It would be interesting to understand the additional electricity required by the pump over time. My pump runs at 1900 RPM most of the day, but solar requires it to run at 2800 RPM. The addition speed uses an additional 800W, so solar heating effectively uses 800W while in use. That’s a rough estimate since the pump will sometimes run at high speed for cleaning anyway, and I’m not suggesting solar isn’t the most cost-effective way to heat, but this cost is often overlooked. Do you have any data on this?

    1. Author

      This is a pretty new phenomenon, but becoming more common as people switch to variable speed pumps. Data is pretty limited and there are so many variables across pools that it would be pretty speculative and inaccurate to use averages in the decision making process. There are ways to mitigate the issue like using panels and plumbing that reduce restriction to flow. You can also shorten the run time and just run your pump when you are most likely to heat the pool with solar panels since the flow rate will be higher and turnover may be sufficient without a wider run window. 800W sounds like a lot more than we typically see. A few hundred RPM is usually sufficient depending on the pool. We do try to set the high-speed cleaning run time around mid-day when solar pool heating is most likely to be on also. All in all, he cost is pretty nebulous fur sure.

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