The performance of an indirect evaporative cooler (IEC) operating to precool mixed air in a variable-air-volume system is experimentally verified in a carefully controlled laboratory environment that realistically simulates performance in a field application. The data are correlated and applied using the methodology described in chapter 36 of the ASHRAE Handbook-1984 Systems (ASHRAE 1984) to calculated energy savings and peak electric demand reduction of this IEC configuration compared to conventional vapour-air compression air conditioning. Results of these calculations for Dallas, Texas, show annual operating savings of 9% in electrical energy for cooling and a slight reduction in peak electric power demand. The seasonal energy efficiency ratio (SEER) for the indirect evaporative cooler is 70% high than that of the backup high-efficiency air conditioner, and nearly 12% of the conventional air conditioning capacity is displaced.

KEYWORDS: experiment, performance, evaporators, indirect cooling, evaporative coolers, air conditioning, variable volume air conditioning, calculating, energy conservation, energy consumption, peak load, comparing, electricity consumption, cooling