Energy Loss in Pools – Part 2

In Blog by TMI Sustainable Aquatics

In our last blog our friend Cory Willis told us a little about the evaporation and how it affects energy loss in a pool.  This week we’ll look at a solution.

____________________________________

Since evaporation is the major source of heat loss for all swimming pools, to minimize evaporation one must cover the pool. Covering the pool with a pool cover when it is not in use is the single most effective means of reducing pool heating costs

Pool covers also provide many other benefits beside the tremendous energy savings. They conserve water by reducing the amount of make-up water needed by 30-50%. They can reduce chemical consumption by 35-60%. They also cut cleaning time by keeping dirt and other debris out of the pool.

It is highly recommended that the first step to cutting pool energy loss be the evaluation of the economics of using a swimming pool cover.

The Department of Energy had prepared a chart years ago that showed the cost savings for covering your pool with a pool blanket when not in use. The typical range for pools is 78°- 82° F. Keep in mind, however, that the energy consumption for each degree rise in temperature will cost from 10-30% more in energy costs depending on your location.

In warmer climates the percentage is higher due to the relatively low cost of heating a pool at 78° F. the chart below shows costs of heating pools in different parts of the country to different temperatures. The figures are based on a 1000 square foot outdoor pool heated with an 80% efficient natural gas heater at $.50 per therm. The pool is uncovered for 8 hours per day.

Location Season Temperature
78° 80° 82°
Miami 1/1-12/31 $1335 $1780 $2250
w/cover 1/1-12/31 $260 $365 $500
Phoenix 3/1-10/31 $865 $1110 $1385
w/ cover 3/1-10/31 $60 $105 $160
Dallas 4/1-10/31 $945 $1200 $1535
w/ cover 4/1-10/31 $115 $175 $255
Atlanta 4/1-10/31 $1065 $1405 $1800
w/ cover 4/1-10/31 $200 $265 $370
Los Angeles 5/1-10/31 $1165 $1485 $1815
w/ cover 5/1-10/31 $105 $190 $295
Kansas City 5/1-10/31 $896 $1170 $1490
w/ cover 5/1-10/31 $180 $260 $340
New York 5/1-9/30 $905 $1190 $1490
w/ cover 5/1-9/30 $130 $185 $250
Chicago 5/1-9/30 $1013 $1295 $1585
w/ cover 5/1-9/30 $135 $185 $240
Denver 5/1-8/31 $1292 $1560 $1835
w/ cover 5/1-8/31 $110 $145 $225
Boston 5/1-8/31 $1070 $1310 $1565
w/ cover 5/1-8/31 $145 $205 $288
Minneapolis 6/1-9/30 $832 $1110 $1360
w/ cover 6/1-9/30 $120 $155 $240
San Fran 6/1-8/31 $975 $1160 $1355
w/ cover 6/1-8/31 $120 $200 $295
Seattle 6/1-8/31 $953 $1115 $1285
w/ cover 6/1-8/31 $190 $265 $345

But if you don’t want the initial expense and lack of storage space for a pool blanket cover, technology has a liquid solar pool cover that you add to your pool water that will cover your pool surface when it is not in use and just needs replacing on average as once a month. When you look at the entire volume of your swimming pool being lost through the evaporation process in a year, putting a “lid” on your pool surface is a smart investment.