The commercial and residential sector demands high cooling requirement, which is mostly achieved
by using conventional cooling systems like split ACs, chillers or VRF. These systems currently produce 100 MT
of CO2 per annum and hence contribute significantly to carbon emissions. To mitigate such environmental
impacts, using low energy cooling systems like an indirect-direct evaporative cooling system (IDEC) is an
energy efficient alternative as it uses energy only for pumping water and blowing air.
This study evaluates the cooling performance of IDECs. The wet bulb effectiveness (WBE %) was calculated
from the hourly measured values of air temperature (Ta °C) and relative humidity (RH %). These parameters
were measured at inlet and supply air. Energy consumption of the IDEC, air blower fan, and water pump were
monitored every hour. Thermal comfort surveys were conducted to establish a relation between the
effectiveness of IDECs, the cooling energy consumption and degree of occupants’ comfort. ∆Ta of 5- 6 °C and
saturation deficit of as 30-35% was observed. During August-October WBE varied from 55-83% with an energy
consumption range of 29-30 kWh. Whereas, for November-December, WBE varied from 41-67% with energy
consumption range of 23-28 kWh.