DE-93-12-3 -- Energy Requirements and Potential Savings for Heated Indoor Swimming Pools

Reports that in a series of tests the rate of evaporation form the quiet water surface of a large indoor swimming pool was measured and correlated with air and water temperature and air humidity. Precise measurements of change in water level and of steam consumption in the pool water heater were both used to determine evaporation rates. Finds good agreement of the two methods. States the form of the evaporation rate equation published in the 1991 ASHRAE Handbook-HVAC Applications was confirmed. Actual evaporation from the quiet water surface varied from 0.020 to 0.055 lb/(h.ft2). These rates are 76% of those obtained by the use of the published equation at the measured conditions. Recommends that a 73% factor be used as a multiplier in the ASHRAE equation for evaporation from quiet indoor pools at elevations less than 1,000 feet above sea level.

KEYWORDS: Testing, swimming pools, evaporation, indoor, air temperature, humidity, water temperature, calculating, energy consumption, heating, ventilation.