Evaporative Coolers
Evaporative coolers, or ‘swampies’ as they are commonly known, have become common fixtures on the roofs of many Victorian homes since the 1960s. Evaporative Coolers are affordable to run based on their low energy requirements and generally have a lower capital cost than their refrigerated counterparts and provide quiet, effective cooling in many highly populated areas of Victoria.
Significantly, an estimated 15 billion litres of water per annum is associated with the operation of evaporative coolers in Victoria, with about 550,000 units operating in the residential sector alone.
An innovative study undertaken by the Australian Institute of Refrigeration Air Conditioning and Heating (AIRAH) in 2011 provides further insights into the water usage of evaporative coolers in the residential and commercial sectors in Victoria.
This study was funded by the Smart Water Fund and involved input from the Department of Sustainability and Environment (DSE), Victorian water corporations, evaporative cooler manufacturers/distributors and the Plumbing Industry Commission.
Evaporative coolers use water in two ways – through the process of evaporating water to provide cool air, and secondly to reduce mineral build up through a bleed off or dump process. The dump process is where excess water is discarded in one go, whereas a bleed system releases smaller amounts over time.
The study found that most residential systems bled or dumped on average 20 litres of water an hour, a significant amount and an area that could be improved. It was also found that a dump system uses less water than a bleed system.
A key finding of the study showed that by operating our evaporative coolers at the correct settings and keeping them well maintained, we can collectively save up to 2.5 billion litres of water per year across Victoria.
Best Practice Guidelines and Plumbers Training
The study results have been used to develop awareness raising material for end users (residential and non residential) and design engineers.
To complement this awareness material AIRAH has partnered with the Plumbing Industry Commission to develop training for plumbers focusing on water efficiency measures for evaporative coolers. The training for plumbers will focus on the modification process for evaporative coolers to improve their water efficiency.
Water efficiency for evaporative coolers Best Practice Guidelines:
Non-residential guidelines (PDF~1MB)
Further information on evaporative coolers can be found on the AIRAH website.