Customers can significantly reduce swimming pool heating costs and energy use by using a pool cover. In the accompanying tables, one can see the costs of heating pools with and without pool covers in different U.S. cities.

For example, a standard size outdoor pool in Seattle operating an 80 percent efficient gas heater for 8 hours a day from the beginning of June until the end of August incurs an annual heating cost of about $2,078. That same pool using a cover costs just more than $200 per year to heat.

Whether the pool has solar, or a gas or heat pump heater, the financial savings is real.

Although pool water loses energy in several ways, evaporation is by far the largest source of energy loss. Evaporating water requires tremendous amounts of energy. It only takes 1 Btu) to raise 1 pound of water 1 °F, but each pound of 80 °F water that evaporates takes 1,048 Btu of heat out of the pool.

Obviously, covers don’t save any energy if they never get used. That’s why it’s important to consider ease of closure and opening, in addition to how often the pool is realistically used. Options range from manual, semi-automatic, or fully automatic pool covers.

Image shows pool heat loss