What should be considered when installing a solar pool heating system?
You made the right decision! To heat your private swimming pool with a solar system. Heating the pool using solar energy is the most efficient, eco-friendly, economical method to extend the swim season. Choosing the proper system depends on various factors that should be taken into account such as: pool size, local ambient temperatures in your regions, ideal water temperature for you, the Sun's position.
We, at Magen eco-Energy, have been manufacturing solar pool heating systems for over a few decades. These collectors have been installed under all weather conditions and almost all regions across the globe. In the next paragraphs we will try to share our professional knowledge about installing a solar pool heating system.
Is the pool in-ground or above-ground?
Above ground pools have the same depth throughout. This piece of information is significant since there is less water to heat compared to in-ground pools that have a deeper end. That said above-ground pools lose heat from the sides which are exposed.
Is the pool covered or uncovered?
During nighttime, when temperatures drop, pool water loses the heat obtained during the day. When using a pool cover, it is possible to maintain 70% of the heat absorbed. If you decide to cover the pool when it is not in use, you will definitely save energy and make the heating process more efficient. Similarly, if you own an indoor pool, it will lose less heat during the night.
What about the weather - is it windy or calm?
For pools positioned next to the beach or in windy regions we recommend using solar collectors that are semi glazed and are designed to perform under windy conditions. To avoid heat loss, it is possible to use a pool cover, build a fence or a trench to prevent the wind from blowing over the pool surface.
Is the pool exposed to direct sunlight?
In pools that are exposed to direct sunlight, energy loss (heat) will be minimal. If the pool is especially shaded, meaning, it's not exposed to direct sunlight, it is always possible to "compensate" by installing additional solar collectors to heat the pool.
Is there space in the yard to install the solar collectors?
If you don't have the available roof space to install the solar system it is possible to install the collectors on a range of straight surfaces - pergolas, the ground, a rack or almost any surface, as long as it is exposed to direct sunlight and all collectors are together or positioned close to one another. Ideally, collectors should be mounted on a flat or tilted roof or on an elevated ground mounted rack facing South in the Northern Hemisphere (opposite in the Southern Hemisphere). If necessary, east facing or west facing roofs can be used (in that order of preference). If you have to mount collectors on a North facing slope, it is recommended to construct a reverse rack. Tip: the ideal angle for maximum solar collection should be similar to the local latitude or up to 15° higher. However, any angle that allows for self-drainage of the panel is sufficient. It is important to remember that if the heat generated by the collectors is not sufficient, it always possible to add additional collectors.
Will you choose manual or automatic control?
It is recommended to operate the solar heating system using an automatic controller that is responsible for directing pool water through the collectors when the pool requires heating and proper conditions exist. The automatic controller monitors the pool water temperature and the temperature around the collectors, and ensures pool water reach optimal temperature (as pre-defined in the controller). The controller will cease and resume its operation automatically. A manual solution usually relies on human memory…..less common and less recommended.
How many square meters/feet of collectors do I need to heat the pool?
In addition to all that is written above, our rule of thumb is that the system size should be 90-100% or pools' surface. For every "cooling" factor, mentioned above, compensation in the form of one or two collectors is required. For example: in a 30m2 [322 ft2] we normally recommend installing 30m2 [322 ft2] of solar collectors. If the pool is fully shaded, we will recommend installing one or two additional collectors.
How do the solar collectors heat the pool water?
At the very instant the controller determines the ambient temperature next to the collectors is higher than the pool water temperature, pool water is automatically directed through the solar system. Water flowing through the individual tubes is heated by the sun and returns to the pool. When the pump circulates the pool water from the pool to the collectors numerous times, pool water temperature quickly rises. The controller will cease directing water through the panels when the desired temperature predefined by the owner is reached. When the controller senses, pool water temperature drops, the pump will once again commence action and the water is heated once more. This is how we enjoy warm water heated by free energy.