Swimming pool heating costs can be significantly reduced by using a pool cover. Use of a pool cover also can help reduce the amount of chemicals (chlorine, etc.) required by the pool. Outdoor pools gain heat from the sun, absorbing 75%–85% of the solar energy striking the pool surface. Though a cover decreases the total amount of solar heat absorbed by the pool, the cover eliminates heat loss due to evaporation and reduces heat loss at night through it's insulating properties. Most swimming pool heat loss is through evaporation.
The heating effectiveness of a cover depends on type. A transparent bubble cover is the most effective, as it allows the largest amount of solar flux into the pool itself. Thermal bubble covers are lightweight UV stabilized floating covers designed to minimize heat loss on heated swimming pools. Typically they are only fitted in spring and fall (autumn) when the temperature difference between pool water and air temperature is greatest. They raise temperature of a pool by around 11 °Celsius, after being on the pool for a week. Bubble covers are typically applied and removed by being rolled up on a device fitted to one side of the pool (see Covers on our Web Page). Covers fall apart after 4 or 5 years due to sun exposure, overheating in the sun while off the pool, and chlorine attacking the plastic. Bubble covers should be removed during super chlorination.
A vinyl cover absorbs more sunlight directly, allowing temperature to rise faster, but ultimately prevents the pool from reaching as high a temperature as a clear cover. Vinyl covers consist of a heavier material and have a longer life expectancy than bubble covers. Insulated vinyl covers are also available with a thin layer of flexible insulation sandwiched between two layers of vinyl to be fitted to pools in areas of that have high evaporation This is an effort to conserve water, as much water evaporates and transpires.
An alternative is a slatted pool cover, which unlike a bubble cover is, ridged enough to put on and off the pool automatically. The slats are buoyant so they float on top of the water and are operated with an electric roller which can be sited either in the pit below the water line or above the deep end of the pool.
Rollers located in the pit end of the swimming pool are great because it leaves the pool deck Un-cluttered and makes the job of pulling on and off the cover light work. This type of cover is very efficient and is available with solar panels and will help maintain your pools temperature during those very cold winter months. Often used in conjunction with a pool heater this is the ideal cover for those who like to use their pool all year around.