Economics
The economics of using evaporative cooling are surprising to most people. An 85% reduction in energy used compared to a conventional air conditioning unit seems too good to be true. Compared to air-conditioning which uses mechanical refrigeration, the operating cost of heat evaporative exchanging are 90% less than air conditioning. There are, now a days in operation, more than 20 millions of residential evaporative cooling in all world, saving approximately 60 millions of petroleum’s drum and avoiding the emission of 27 billions of CO2 pound yearly. In the USA, only the fair of residential evaporative cooling moves US$ 180 millions in the year, with more than 4 millions of units installed. The cost per unit of equipment is between US$ 35 for simple direct system and US$ 2,000 for completely systems with ducts, and the average cost between US$ 300 and US$ 700. The direct settling reduce the operation costs between 25% and 40% when it is compared with costs of mechanical refrigeration only, to produce the same cooling effects. A direct/indirect system accounts for saving between 40% and 50% energy in moderately wet areas. On farm evaporative cool storage was found to be technically feasible at reducing potato storage losses by as much as 50% over farmer’s methods. However, the additional cost of ECS may be too high to encourage widespread adaptation.