Evaporative chilling, the use of cooling towers t remove heat from a chilled water system directly, is an energy saving strategy that works particularly well in dry, cool climates with low average wet bulb temperatures. Because wet bulb temperatures are generally lower during the winter and at night, evaporative chilling has enjoyed use as a “free cooling” measure in meeting continuous cooling loads such as computer or industrial process cooling needs. Its use with building air conditioning systems, however, has been limited. HVAC designers have favored outside air cooling economizers when seeking to reduce typical building air conditioning energy use.