Sizing a Solar Swimming Pool Heating System
In general, the surface area of your collector should be equal to at least 50 percent of the pool's surface area.
Photo credit: Aquatherm Industries.
Sizing a solar swimming pool heating system involves many factors:
- Pool size
- Length of swimming season
- Average regional temperatures
- Desired pool temperature
- Site's solar resource
- Collector orientation and tilt
- Collector efficiency
- Use of a pool cover.
Solar system contractors use worksheets and computer programs to help determine system requirements and collector sizing.
Basically, the surface area of your solar collector should equal 50%–100% of the surface area of your pool. In cooler and cloudier areas, you may need to increase the ratio between the collector area and the pool surface area. Adding collector square footage also lengthens the swimming season.
For example, a 15-by-30-foot outdoor swimming pool in Florida typically requires a collector that equals 100% of the pool's square footage to accommodate year-round use. This equals 450 square feet of collectors. In northern California, most people use outdoor pools 6–8 months per year, so they typically size their systems at 60%–70% of the pool's surface area.
In any climate, you can usually decrease the required collector area by using a pool cover.
You'll also want a properly sized pool pump for a solar system. If you're replacing a conventional pool heating system with a solar system, you may need a pump larger than your current one or a separate, smaller pump to move the pool's water to and through the collectors.