If you are a new swimming pool owner, you may be wondering how to heat a swimming pool for free.  You may not have selected the pool heater you want to use.

Or the heaters you have looked at may not be cost-effective.  Don’t let this worry you.  If you are looking at how to heat a swimming pool for free then we’ll provide you with some answers.

We’re here to show you cost-effective ways to heat your swimming pool. This way you will be able to keep your pool warmer without going to great expense.

You’ll learn the different ways of keeping your pool heated.  You will also learn how your pool loses heat and how to prevent this.

By putting these tips into practice, you’ll drastically reduce your pool’s heating costs.

Now that you know there are cost-effective ways of keeping your pool warmer, let’s have s look at how they work.

How to heat a swimming pool for free?

Geometric-Outdoor-Inground-Swimming-Pools-by-Platinum-Poolcare How to heat a swimming pool for free (well, almost free)
Image source: Platinum Poolcare

Let’s go back to our earlier question of how to heat a swimming pool for free?  To do this, you would use solar power and heat retention.  Apart from the installation costs, you will not pay to heat up your pool.

Using a black hose to keep your pool warm

blackhose How to heat a swimming pool for free (well, almost free)

Black hose makes a great pool water heater.  You can use it to capture the sun’s energy and heat your pool.  As dark colors retain heat, a black hose will provide natural pool heating.

This is how it works:

All you need to do is buy a black garden hose.

Purchase a black garden hose long enough to travel the distance from your pool pump and into a sunny area with 100 feet to spare. To keep your pool warmer, pick a spot on the deck or on the roof of your house.

After you have chosen the spot, it is time to unravel your hose.  Connect it to the return in your pool pump.  You can do this using a tap-style connection.  You might have to have this connection professionally installed.

Once you have attached your hose, run it to your chosen sunny spot.

Wrap all of your spare hose into a coil.  The coil will help the hose to remain warm.  Then run the remaining hose into the pool.

Warm water will circulate through this heated coil, creating a pool water heater to increase your water temperature.

Cost: $80 – $150 

Solar Cover

Solar-Cover How to heat a swimming pool for free (well, almost free)

If you are looking for a cost-effective pool warmer, a solar cover makes a great option.


One of the main causes of heat loss in a pool is evaporation.  Water evaporates during the day.  Gusts of wind and the heat of the sun cause water loss.  When you remove water that is already warm, you will cool down the temperature of your pool by adding cooler water.  This is unless you prevent evaporation from occurring.

A solar cover presents the perfect barrier to evaporation.  It not only provides a shield against water loss but it also acts as a cheap pool heater.  This is because a solar pool blanket will help you to retain heat.

By cutting down evaporation, you’ll be cutting down on 75% of your pool’s heat loss.  This will help you save on the costs of heating your pool.

Cost: $50 – $200

Heating your pool with solar panels

solar-panel How to heat a swimming pool for free (well, almost free)

Solar panels convert sunlight into energy.  They are a cost-effective and environmentally friendly way of heating a pool.  They can also be combined with an electric heating system to add warmth to your pool.

If you are wondering how to quickly heat a pool, solar panels are your best option.  Combine them with your electric heating system for rapid results.

The cost of installing this heating for pools will depend on the size of your pool and the number of panels you will need.  You’ll also need to find out the capacity of the panels you wish to install.  The larger your family, the more energy you will need to heat your pool.

If you choose to install solar panels, you will need a large surface for them.  This surface will need to be in a sunny spot.

Solar panels are environmentally friendly and the sun’s energy is completely free.  However, the initial cost of installing solar panels is very high.

The benefits of solar panels as pool water heaters

Solar-Pool How to heat a swimming pool for free (well, almost free)

You will be able to use a controller to create an automatic solar pool heater.  You can adjust your thermostat in the same way you would your water geyser.

Once you set your pool temperature, your controller will adjust the water flow into your panels so that you can get the water temperature you want.

Your automated pool heater will sense the water temperature.  As well as the air outside of your pool.  When the temperature is high enough to warm your pool water, it will open up the valves to heat up your pool.

If the weather is cold or chilly, and will cool down your pool water, your automated controller will close the valves.  This will prevent the panels from cooling down your pool water.

You should also be able to use your automated controller for other areas of pool care or maintenance.  By adding your pump or filtration system and your lights or vacuuming system, you’ll be able to make pool maintenance easier.

Using dome – shaped connectors to heat your pool

dome-shaped How to heat a swimming pool for free (well, almost free)

Solar dome connectors work in a similar way to solar mats.  However, with a dome connector, the piping is rolled up into a dome shape.  Heating for pools takes place within this dome.

Solar dimes take up far less space than solar mats.  A 8 x 4 meter pool which is 1,5m deep will only need ten domes.  This because each dome heats up a large amount of water.

It is best to use solar domes for small pools.  This is because, like solar mats, domes are dependent on sunlight.  You will also use a lot of energy to push water into and through, the domes.

Domes are slightly cheaper to buy than solar mats.

Solar ring heaters for pools

solarring_heater How to heat a swimming pool for free (well, almost free)

If you want to solar heat your pool but are not yet ready to buy a solar pool blanket, you could always use solar rings.

Solar rings are like a solar pool cover broken into smaller rings or circles.  They make cost effective heating for pools.  They are also very easy to use.

All you need to do is throw a couple of solar rings into your pool.  The amount you will need will depend on the surface area of your water.

Your rings will absorb heat while they float.  They will also connect to each other, locking together to heat your pool.  This is because each of  the solar rings have a magnet which attracts them to one another.

Solar rings create  21,000 BTUs of heat per day

Cost: $50 – $250

Heat pool water with a floating blanket

floating-blanket How to heat a swimming pool for free (well, almost free)

A floating blanket helps to protect your pool from evaporation.  The blanket is made out of vinyl and has air bubbles to help it float.

If you use this blanket it will heat pool water by retaining heat.  It does an excellent job but it is not safe for children.  In fact, the blanket presents a safety risk.

As the blanket is free floating it can wrap around a person who stands on it, presenting a hazard.  This isn’t a great pool heating choice for families with small children.


If you’ve been asking how to heat a swimming pool for free, you’ll see that there are many different ways.  Heating a swimming pool can be cost-effective.  By heating your pool you will be able to extend your swimming time.  We hope you have found this article useful and will be able to find an effective solution to heating your pool.

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