Solar heaters are the most popular method of heating swimming pool water in Australia. But if you are looking to invest in a solar heating system for your backyard pool, it is important to do plenty of research. Solar heating has advantages and disadvantages, and with so many different systems on the market, it’s essential to choose the right system for your pool and the conditions where you live.
This is why we have put together this handy guide to solar pool heating, containing everything you need to know to help you make the right purchase decision.
How Does Solar Pool Heating Work?
Solar pool heating is the cleanest, most environmentally-friendly way of heating your pool water. It harnesses the natural energy from the sun via a solar collector. The pool water is pumped through a series of tubes over the solar collector at a constant rate. It is returned to the pool at a warmer temperature, and as the action is constant, it ensures the heat reaches all areas of the pool.
The pump requires a very small amount of electricity — usually under 1kW per hour — to run. Aside from this, all the energy used by the system is derived directly from the sun.
The Advantages of Solar Pool Heating
As solar pool heating runs almost exclusively from the natural, renewable energy source of sunlight, it is a safe method of pool heating that is kind to the environment.
Solar heating is also by far the most cost-effective means of heating your swimming pool water. The prices of gas and electricity are rising all the time, so installing a solar heating system for your pool will save you a significant amount of money on your energy bills. Many systems now come with automated controls, enabling you to set your chosen water temperature and times of operation. This reduces energy wastage even further, and saves you even more money.
Solar heating systems are also relatively cheap to install. The average cost of a system, including installation, is between $3,000 and $6,000, which can easily be recouped in the savings you will make on your household bills.
If you do not currently have a pool water heating system installed, a solar heating system will enable you to get more enjoyment from your pool. Even in the height of summer, most pools are not warm enough to relax in comfortably, as the water temperature is always cooler beneath the surface. Those who live in cooler parts of Australia can sometimes only use their pools for three or four months of the year. A solar heating system can increase the temperature of your pool water by anything between two and 10°C, making it much more comfortable for swimming and relaxing in. It also enables you to use your pool in the spring and autumn as well as the summer.
Moreover, solar heating systems are extremely low-maintenance, with many continuing to work efficiently for up to 10+ years without needing to be repaired or replaced.
The Disadvantages of Solar Pool Heating
If you live in a warm climate that gets a lot of sunshine, a solar heating system should be sufficient on its own to warm your pool water to a comfortable temperature for most of the year, and perhaps even all year round. However, solar heating systems are not nearly as effective in cooler parts of the country with more frequent cloudy or rainy conditions. They can even be less efficient in windy weather.
This means that if you live in a cooler state, you may need to run your solar heating system in conjunction with an electric pump or gas system if you want to enjoy your pool for more months of the year.
Solar heating can also sometimes be slow to warm the water and will not be able to achieve the same temperatures on different days, as it depends on the weather. If your pool has a spa section, you will need a higher, more consistent temperature to benefit from hydrotherapy treatments, which makes a gas heater a more suitable solution.
The Different Types of Solar Pool Heating Systems
All solar pool heating systems work on basically the same principle, with the water being pumped out of the pool, through the system which has been heated by the sun, and back into the pool at a warmer temperature.
However, there are a number of different types of solar heating systems that operate slightly differently and come with their own set of benefits.
1. Thermal Solar Collectors
These are the most common types of solar heating systems. The solar collectors, sometimes known as solar panels, are usually positioned on the roof of your house, although sometimes they can be located nearer to the pool.
The most affordable solar collectors are made from rubber or plastic matting, and your pool water is passed over them via a series of tubes. These solar collectors are ideal if you live in a warm, sunny climate, but they are not usually as effective in cooler temperatures. This means they may not heat your pool for as many months of the year, but they can be used in conjunction with other forms of pool heating.
Glazed solar collectors are much more efficient. However, they are made from toughened glass, copper, and aluminium, which means they are also much more expensive. However, glazed collectors are far more effective at collecting heat in cooler weather, so they are a more sensible choice if you live in a cooler, cloudier area. They can often provide enough heat for you to enjoy your pool all year round.
2. Evacuated Tube Collector System
An evacuated tube collector system is considered to be the most efficient heating method for swimming pools, although it is significantly more expensive than a thermal system. It is likely to cost you at least 20 percent and up to 100 percent more. However, evacuated tube collector systems are much more reliable at collecting heat, even in cooler climates. This means your pool water will achieve a warmer temperature and heat more quickly.
An evacuated tube collector system has a network of small glass tubes within larger glass tubes, creating a vacuum between the two. As the sunlight heats the glass, the heat is trapped in the vacuum and transferred to a heat exchanger. This is attached to a water box.
The pool water is pumped through the water box, where it is warmed by the heat exchanger before flowing back into the pool at a higher temperature.
These systems are ideal for climates that receive less sunlight, as they are much more efficient at containing heat energy due to their insulation system. The water can be heated to a higher temperature, even when there is not much sunshine or the weather is windy.
3. Solar Pool Covers
A solar pool cover is a solution for people looking at purchasing a pool with a swimming pool cover. Solar pool covers are usually made out of the polyethylene (PE) bubble layer formed in a profile that is consistent in thickness. They enable you to save more of the sun’s warmth – on some days, your pool can warm up up to 8˚C. On top of warming up the pool water, solar pool covers foster water savings, save on heat loss, cleaning and chemicals. They are typically priced in the $1,500 to $3,000 range.
Things to Consider When Choosing a Solar Heating System
Bigger pools need more heat, so the size of your solar collector should be appropriate for the size of your pool. Ideally, your solar collector area should cover at least 80 to 100 percent of the size of your pool in metres squared.
Your collector should also be positioned in an area where it is going to receive maximum exposure to sunlight. It’s best if it can face north, although it will still be almost as effective if it faces up to 45 degrees from north in either direction. However, make sure your solar collector is not positioned in the shadows of trees or tall buildings, as this will reduce the amount of heat it can produce.
If you want to make your solar heating system even more efficient, you can use a pool cover whenever your pool is not in use. This will help the water to retain a warmer temperature. Choosing a cover in a darker colour is even more beneficial because it will absorb more heat from the sun and warm the water to a higher temperature, so the pool will feel more comfortable as soon as you get in — even before the system has had chance to heat the pool thoroughly.
Having Your Solar Pool Heating System Installed
All solar pool water heating systems should be installed by a licensed professional, and it is essential to consult with them first to make sure you are choosing the most efficient heating system for your pool. This will depend on the climate where you live, and whether you are running your system in conjunction with any other type of pool heating. Most solar heating systems require separate pumps and lines suitable for solar power.
You should also choose an established, experienced company that offers extended warranties. Many companies now offer warranties of 10 years or more on solar heating systems. Make sure the warranty covers you for all kinds of damage, and that the system itself is fit for purpose and suitable for the climate in your state or territory.
If you would like more advice about choosing a solar water heating system for your pool, please contact us. Our highly experienced team can answer all your questions, giving you the confidence to choose a solar heating system that will continue to warm your pool for many years to come.