After the excitement of installing a new pool, when the initial novelty has worn off, most often, it only gets used for a few months each year. Heating your pool not only serves to increase the value of your home, but it results in the family spending more time through the year using it, making your investment so much more worthwhile. Do solar power heater works for this purpose well?
Solar pool heaters do work, and they are one of the best uses of solar power. Depending on the technology you decide upon, a solar pool heater is very cost-effective. Not all solar pool heating systems are equal, and you must choose the best technology wisely.
Solar pool heaters have advanced since the old pool heat pumps, which were inefficient and energy-intensive. These systems often required 5kw of energy to produce 1kw of heat. The new systems used either in isolation or together generate energy much more efficiently.
Do Solar Pool Heaters Work?
Yes, heat pumps do work. Several different technologies are available, and each has its pros and cons. Some can plug into an existing solar electricity system; in these instances, make sure that the power draw is within the capabilities of your system.
Each type of solar pool heating system is explained in more detail in the section below:
Heat Pumps Are The First Choice
Modern heat pumps are efficient and a considerable improvement on the older technology. They don’t use electricity to create heat (which would involve a high energy workload). Instead, heat pumps effectively operate on the reverse basis to your domestic refrigerator.
- Your regular swimming pool pump draws the water through the filter, and instead of going straight back to the swimming pool, it is first directed through the heat pump.
- The only energy the heat pump uses is the amount that is required to drive a fan. This fan draws the warm air from the surrounding environment through a piping system filled with non-CFC refrigerant.
- This action transfers the heat from the environment to the refrigerant.
- The refrigerant is compressed, which makes it super-heated. The resultant heat is transferred to the water, which is then returned to the pool.
- A swimming pool heat pump can adjust the temperature of a pool fast
- Modern heat pumps use only 1kw of energy to generate 1 kW of heat, which is substantially more effective and efficient than the old technology.
- The impact on your solar power system will need to be calculated to ensure sufficient capacity is available.
The downside of modern heat pumps is that they do not work in icy environments. As they operate by drawing the heat from the surrounding air, there is insufficient energy for the heat pump to extract if it is too cold.
Solar Heating Cover Are Effective Technology
Solar heating covers work by trapping the free energy released by the sun. Energy transfers to the water resulting in the water heating up.
The best combination of technologies is when a solar heating cover is used with a heat pump. Both the heat pump and the cover work to heat the water during the day, and the cover helps reduce the heat loss overnight.
Another benefit of solar heating covers is that they reduce evaporation and save on water costs.
Are Solar Mats (Panels) Worth Considering?
Solar mats are solar tubes installed on the roof of a house.
The pool water is pumped through the tubes and into the mats after being filtered. Similar to heating covers, solar mats trap the sun’s energy and transfer this as heat energy to the water as it passes through.
Solar mats don’t require any outside power source as they use the water pumped by the filter motor.
To be effective, they should be installed on the roof closest to the pool.
Inclement or cloudy weather will affect the ability of the mats to heat the water.
Dome Shaped Collectors Are An Interesting Option For Very Small Pools
Dome-shaped collectors are a unique consideration for small swimming pools or hot tubs. Using the same principles as Solar Mats, pipes are installed into a dome-shaped device.
As the water is pumped through the dome-shaped device, the free energy from the sun is transferred to the water resulting in the water heating up.
The downside of Dome-shaped collectors is that they generally can only heat 5,000 liters of water each day; this makes them ineffective in an average size pool of 50,000 liters. However, it does make them a viable option for tiny splash pools or Jacuzzies.
Which Technology Gives The Most Bang For The Buck?
A few factors should be considered when evaluating the various available devices. The most important questions are:
- Your heating system should be able to heat the water between 0.2°C and 0.25°C per hour. In an eight-hour day, you can expect a temperature rise of 2.0°C.
- What is the desired heat for the pool?
- What is the ambient temperature?
- What is the size (volume) of the swimming pool?
- How long will you allow for the pool to heat up?
For our example:
- The pool will be an average size measuring 8m x 4m with an average depth of 1.5m
- The ambient temperature is 20°C
- The desired pool temperature is 28°C
- The system must achieve the desired temperature in 48 hours
On this basis, the following cost/benefit analysis is achieved.
Heat Pumps In Combination with A Heat Blanket
Without a blanket, you will need a heat pump with a power rating (heating ability) of 16.68kw (Cost US$ 650.00)
With a heat blanket, you will need a heat pump with a power rating of only 10.56kw (Cost US$ 450.00) to achieve the same benefit.
A Solar cover for this pool will cost +-US$150.00. If they are combined with the smaller heat pump, a total cost of US$ 600.00 results. In addition, a heat blanket will add the other advantages previously discussed.
If your primary solar system can manage the power requirements of a swimming pool heat pump, this combination is the technology that offers the best return.
Solar Pool Mats (Panels)
Solar pool mats can be tailored for the above variables, including how long you want to use the pool through the year.
If you want to add the “shoulder months” (two months on either side of spring and autumn), the solar mats can be sized to 50% of the pool area. If you want to use the pool for 8 – 10 months, you will need panels measuring the same area as the pool.
In the example set out above, the mats will need to be 32m2. These will cost approximately US$1,000
Conclusion
Swimming pool solar heating systems have come a long way in the last few years. The available options offer a real improvement in swimming pool temperature management.
Solar heat pumps are now an efficient and reliable method to heat your pool and make it useable for the majority of the year.