Solar pool heating is an eco-friendly solution that harnesses the sun’s energy to warm your pool water, offering a cost-effective heating solution that can extend your swimming season by months.
All solar heating systems operate under the same basic premise, regardless of the brand or model. Pool water is circulated through a series of tubes known as ‘the collector’. This is generally made of EPDM rubber or PVC/TPR and assembled into multi-tube panels which are located on the roof of your home. When water travels through the collector it absorbs heat from the sun and is returned to the pool as warm water. Couldn’t be simpler.
Just because it’s simple, doesn’t necessarily mean it’s effective. There are a range of physical and environmental factors that influence the efficacy of a pool solar heating system, so it’s worth a bit of pre-planning to get it right.
Collector size and density
The collector area is usually expressed in m2. The larger the area, the more efficient the system becomes. As a rule, collector density correlates directly with your pool's surface area.
Ideal location
The ideal location is one that enjoys direct sun exposure throughout the day. In the southern hemisphere, that means placing the collector on a north-facing roof. It is possible to achieve a little extra performance through proportional increases in the collector area, but the highest gains will always be from solid direct exposure to sunlight – six unobstructed hours per day is ideal.
Control system
You can control heating demand by using a temperature-sensing system. It will ensure that the heating only kicks on when the sun’s energy can be effectively harnessed.
Determining the appropriate collector area is a bit of a balancing act between efficiency and your pool's unique characteristics. The Australian Standard AS3634 governs solar heating systems for swimming pools and offers practical guidance. Using Sydney, Newcastle and Wollongong as an example, the standard suggests the collector area should be about 60% of a pool's surface. However, variations in local climate, shading, roof orientation and the collector type all call for adjustments to ensure an optimal result. SPASA suggests a minimum area of 80% for most installations offers a more balanced outcome.
Efficient water circulation relies on the right pumping setup. This can be either a dedicated pump or your existing pump, but only if it meets the following critical criteria:
It must maintain the required pool water turnover rate for filtration purposes
It must not exceed the manufacturer's maximum pressure limit if the solar circuit is added
It must have capacity to handle the static head and friction losses introduced through addition of the solar circuit
The average domestic solar installation requires a minimum flow rate of around 100 to 200 litres per minute to operate effectively. In most circumstances this means a dedicated solar pump is required.
When selecting your pump, check that the collector’s minimum design flow rate can be met – this will vary depending on the tubing diameter. In addition, when using a dedicated pump, you’ll need to include a strainer to prevent dirt and debris blocking the collector as the water circulates.
For obvious reasons, timeclocks are ineffective for controlling solar systems. Temperature-sensing controllers are a far more practical solution, operating the pump system only when heat can be gained from the sun, maximising efficiency and preventing the cooling effect of circulating water through a cold collector.
Once your system is installed and handover complete, you should have the following information:
Certification – a document certifying successful installation and commissioning of your system.
A comprehensive component list – this should outline major components and equipment details, including collector size, control system specifics, and pump specifications.
Warranties – copies of warranties from both component manufacturers and installers.
Operational guidelines and equipment manuals – these should outline the operational, maintenance and servicing instructions in an easily understandable format.
Installer information – records of installation dates and contracting installer details.