How Do I Use a Solar Cover on a Pool?

Solar pool covers can help stop algae growth.
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Solar pool covers can have surprising benefits. Chesaning Union School in Michigan, for example, reduced its energy costs by 55 percent, saving $9,000 a year, simply by installing a solar pool cover (see References 1). That level of savings is not unusual. Anyone can save on energy, water and expenses related to heating by installing and correctly using a solar pool cover.

Understanding Pool Covers

Swimming pools lose energy primarily through evaporation. Evaporation rates vary based on the pool and air temperature, air humidity and wind speed. Higher temperatures and wind speeds and lower humidity result in faster evaporation and added energy costs, even for indoor pools. Pool covers minimize evaporation, which can save up to 70 percent on heating costs. On outdoor pools, solar pool covers do even more: They collect solar energy and transfer it into pool water as heat. (See References 2)

Choosing Your Cover

Among the several types of solar pool covers, the most affordable is a bubble cover, which looks much like bubble packing material but is made of thicker plastic. Vinyl covers are constructed of heavier material, and usually last longer but cost more. Insulated vinyl covers are the most costly, because they consist of multiple layers of vinyl that improve heat entrapment. Be sure not to choose an opaque cover; the solar cover should be clear or translucent to help the pool collect solar energy. (See References 3)


Multiple methods work for installing a cover; the simplest and cheapest is simply to cover your pool manually. However, that can take some work. You can also buy a pool cover reel that rolls the cover up automatically or manually. Choose the option that fits your budget and your lifestyle. A improperly used pool cover provides limited benefits. (See References 3)

Daily Use

Keep your solar pool cover in daily use throughout the swimming season. The most effective method is simply to remove the cover when the pool is in use, and then replace it when the swimmers are finished. Because solar pool covers are not completely transparent, they can reduce solar energy absorption by 5 to 15 percent. In areas with dry air and brisk winds, however, protecting your pool from evaporation more than makes up for this loss. You should consider the temperature differential between your pool water and the air, as well as humidity and winds in your area, when deciding whether to cover your pool during the day or leave it uncovered. During the months when your pool is not in use, remove the solar cover and store it. (See References 3)

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