Can you heating a swimming pool with solar? (FAQs + Buyer’s Guide)

Yes, you can use solar power to heat your pool by using a “solar pool heater system”. As this system uses the energy of sunlight, you can heat your pool without any cost.

You do not have to worry about huge electricity bills at the end of the month by using a solar pool heater system.

Like any other system, this system also has both pros and cons. In this article, we will cover all the main facts you must know about the solar pool heating system.

How do solar pool heaters work?

A standard solar pool heater system consists of:

• Solar collectors– to collect and transfer the heat to water circulated through them

• A pump– to circulate the water through the system

• A filter– to remove the debris

• Control valves– control the water flow. These valves can be either manual or automatic. If the valves are automatic, then the system also comes with heat sensors to identify the temperature of the pool water and the collector. This allows circulating the water through collectors only when the collector temperature is higher than the pool water.

• Auxiliary/ backup system (Conventional pool heater)– this system will heat your pool when there is not enough heat collected in solar collectors to heat your pool.

Solar collectors will absorb the sun’s radiation/ energy and converts it to heat. The pump circulates the water through the system. When you switch on the pump pool water starts to circulate through the pipeline.

First, it goes through the filters. The filter will remove any debris contained in the water. Then the water goes through the solar collectors. The heat will transfer from the collectors to the water.

Then the water will flow back to the pool.

The water flow can be controlled by using a controlling valve. These controlling valves can be either manual or automatic. With manual controlling valves, you have to control the system manually. You have to decide the time you need to on the water circulation through the system according to the temperatures of the pool and the collectors.

But if you use automatic control valves you do not have to worry about opening and closing the valves manually. By using heat sensors the system will measure the temperature of the pool and the solar collector. When you switch on the system water will flow through the solar collectors if the solar collector temperature is higher than the pool temperature. When the solar collector temperature becomes equal to or less than pool temperature the system will bypass the solar collector and water will flow back to the pool

Advantages of having a solar pool heater

• No bills– using electric pool heaters will increase your electricity bill as electric pool heaters consume so much power. But using a solar pool heater can reduce your electricity bills as it does not require grid power. By using a solar pool heater you can enjoy a warm swimming session without worrying about huge electricity bills at the end of the month. Using a solar pool heater will save you a good amount of cash at the end of the month.

• Less maintenance cost– when compared to the other pool heating systems, solar pool heating systems have less maintenance work.

• Environmental friendly– as we all know, solar energy is a 100% clean and renewable energy source. Using solar energy does not release any harmful substances to the environment. Using grid electricity or any other fuel to power up heating systems will release many harmful substances to the environment. So using a solar pool heating system will save both your money and the environment.

• Increase the property value– in some countries and states installing solar panels or any solar-powered systems such as solar pool heaters or water heaters increases the property value,

Disadvantages of a solar pool heater

• High initial cost– when compared to the other pool heating systems, solar pool heating systems are expensive.

• Need extra space to fix solar collectors– you need extra ground or roof to fix solar collectors.

• The system’s efficiency depends on the availability of the sun– like from other heating systems we cannot expect constant efficiency from the solar pool heaters. The reason is the system’s efficiency depends on the sun and the sun varies all the time. We cannot expect sunlight/ radiation to be constant all the time.

FAQ –

How warm can a pool get with a solar pool heater?

With ideal conditions, solar pool heaters can heat your pool 8 – 12 degrees above the temperature of an unheated pool.

But this depends on many factors;

• Environment temperature– when the environmental temperature is very low, it is harder to go for higher temperatures as it is hard to absorb the heat by solar collectors. Also, when the environment temperature is low it increases the heat loss from the pool surface. So this makes heating the pool harder.

• Availability of sunlight– having good sunlight will increase the heating.

• The efficiency of solar collectors– having solar collectors with good efficiency is important to warm your pool properly. Solar collectors with good efficiency can absorb heat even in low sunlight. Also, as they effectively speed up the heating more than the speed of the cooling process your pool temperature increases higher than the low efficient pool heaters. Also, they can heat your pool quickly.

• Size of solar collector– the size of the solar collector is very important as it decides the amount of heat delivered to the pool. So it should be enough to absorb enough heat to increase the temperature of the pool. The general rule to select a solar collector size is, “solar collector surface area = half of the pool surface is”. But this is affected by many other factors.

• Pool size– when your pool has less surface area, it is easier to warm up as the heat loss is less. Also, it can easily go to higher temperatures as it has less water volume. But if your pool size is large then it needs a lot of heat. So to heat your pool efficiently you have to select the solar collector size, efficiency, orientation, location, etc carefully.

• Wind – if the location is windy it is harder to heat the pool for higher temperatures as the heat loss increases.

How long does it take to heat your pool with a solar pool heater?

This depends on many factors;

• Expected temperature– it takes more time when the expected temperature is high.

• Environmental temperature– when the environmental temperature is low it is hard for to solar collector to absorb the heat. Especially if they are unglazed solar collectors. Also, heat loss from the pool surface is high at low temperatures. So it takes more time to get to the expected temperature when the environmental temperature is low.

• Pool size/ water volume– if the pool size is large it takes more time as the water volume is high.

• Efficiency and size of the solar collector– when the solar collector efficiency is high, it can absorb the radiation/ sunlight and convert it to heat more efficiently. So they take less time.

• Availability of sunlight– when there is good sunlight the system heat up the pool more efficiently. So it takes less time.

• Wind– when the wind is high the heat loss increases. So it takes more time to heat the pool on windy days than normal days.

Cost to install a solar pool heater

The average cost is about $2500 to $4000 to buy and install a solar pool heater system.

This value varies according to the state or country you are living in and the manufacturer/ solar provider you choose.

How do size the solar pool heater you need?

The general rule when calculating the solar collector surface area is;

Solar collector surface area = half of the pool surface area

But this is not always true. You have to consider the following factors as well to decide the solar collector surface area.

• Pool size – for a large pool you need more solar collectors than for a small pool. The reason is when the pool is large you have to heat more water volume. So the solar collector surface area also should be large enough to absorb an adequate amount of heat.

• Environmental temperature – if you are living in a low-temperature area then it is hard to heat the pool as the heat loss is higher at low temperatures than at high temperatures. So the solar collectors have to be more efficient and large enough to supply adequate heat to heat the pool.

• Usage ( season & Day/ Night)– we have to be practical in this matter. As most pools are outside it is harder to keep the pool heated during winter or night. Even though you used a backup heating system it is hard to keep the pool heated during the winter season. If you want to use your pool in a very cold climate you have to go for glazed solar collectors with more efficiency and large surface area. But on summer nights it is not much of a problem. But you may have to use a large solar collector surface area and a good pool cover to keep your pool heated during the night.

• Solar collector efficiency– if the solar collector efficiency is high you can reduce the solar collector surface area.

• Desired pool temperature– when the desired temperature is high you need to increase either solar collector efficiency or solar collector surface area. Also, you can increase both if the desired temperature is very high.

Things you should consider before purchasing a solar pool heater

• Solar provider/ manufacturer – selecting a qualified solar provider/ manufacturer is very important when you are purchasing solar-powered items/ systems. As items are very expensive there are many fake products available in the market for a lesser price. But most of the time they do not work efficiently and their lifetime is also very less. So by purchasing products from a qualified manufacturer you can get all the advantages from your solar product. Also, if you purchase a genuine product then you can avoid lots of maintenance and repair expenses later.

• Solar collector type and efficiency – solar collector is one of the main parts of the solar pool system. if you hire a solar provider they will choose the right solar collector type with adequate efficiency according to your location, shading, climate, usage, etc.

• Adequate size of the solar collector – as we said earlier there are many factors to be considered when sizing the solar collector area you need. As it is not a simple task it is better to hire a qualified professional who can calculate the adequate size of solar collectors.

• Warranty

When you decide to go solar: Find a quality solar pool panel sales company and talk to them directly. The internet is also a great way to educate yourself on pool panels and the company you are dealing with. Remember to measure the size of your pool so that the company knows what size of panel you are looking at using. Another good thing to do is to take photos of the area around your house and pool. This will give the company ideas on what your obstructions are and find the best way to place the panels.

What is the best solar collector for your solar pool heater?

There are mainly two types of solar collectors;

• Glazed solar collectors
• Unglazed solar collectors

When selecting the most suitable solar collector for your pool water heater system you have to consider the following factors;

• Climate/ weather in your area
• Usage