Solar Heating in Your Pool

The arrival of Earth Day is an annual reminder to think about energy efficiency, but it really should be a topic to consider all year round.

One very effective and relatively easy way to recoup significant energy savings is to heat your swimming pool with a solar panel system – particularly if you compare the installation and operations costs (for solar, much of that is the former, then the system becomes self-sustaining over time; with propane, you’ll have less initial expense but an ongoing operation cost). Depending upon how much sun the panels get, you could have enough heat to raise pool water temperature by as much as 15-30 degrees.

Imagine a garden hose lying in the sun. When you turn the water on, the first blast is typically warm, if not actually hot, since heat has been accumulating in the plastic tubing. That’s the basic theory of solar heating, with a few other moving parts.

How Does Solar Heating Work?

It’s a simple proposition: Water is circulated from the pool into a solar collector (more on this next), where it is exposed to the sun’s energy. Once the water in the collector becomes warmer than the pool water, a valve releases it back into circulation in the pool, and this cycle continues as long as the water in the panels is warmer than the water in the pool.

Types of Solar Collectors

There are different kinds of solar collectors, and the type you’ll need depends mostly on two things: the specific use(s) for the system and the climate in your area.

For instance, if you’ll only be using your pool seasonally, an unglazed collector system is a likely choice. Unglazed collectors don’t include a glass covering (glazing); instead, they are constructed of heavy-duty rubber or plastic treated with an ultraviolet (UV) light inhibitor to extend the life of the panels. This is a simple design with inexpensive parts, so it’s less expensive than its glazed cousin.Solar heating panels near a poolMeanwhile, glazed collector systems are generally more complex – involving copper tubing on an aluminum plate with an iron-tempered glass covering – and are therefore more expensive. However, glazed collector systems typically capture solar heat more efficiently than unglazed systems, so they make more sense for colder weather areas where you hope to extend your pool heating panels on a roof poolsideFor additional information about solar swimming pool heaters, visit the Department of Energy website.