Does Evaporative Cooling Use Gas or Electricity?
Evaporative cooling systems are an economical alternative to refrigerated air conditioning, but a fundamental question often clouds the conversation: what energy source do they use?
Many homeowners wonder if evaporative cooling uses gas or electricity, or a combination of both. The uncertainty often stems from homes that have gas ducted heating, leading to the assumption that a ducted cooling system might also use gas.
And if you have add-on cooling to your gas ducted heating, it does. But evaporative cooling systems are different to refrigerated cooling. In short, evaporative cooling systems run exclusively on electricity, not gas.
However, unlike reverse cycle air conditioning, the electricity isn’t used to create coldness through a chemical process. Instead, it powers the mechanical components that enable the natural process of water evaporation, which is what actually cools the air.
Table of Contents
Electricity Powers the Fan Pump and Motor
The system’s electricity consumption is limited to two main components: a powerful fan that draws air into the unit and pushes it into your home, and a small water pump. This pump circulates water from the unit’s reservoir (water tank) to saturate the cooling pads.
The real cooling magic happens when hot, dry air is pulled through the water-soaked pads. As the water evaporates, it undergoes a phase change from liquid to gas, a process that absorbs heat from the air. This natural process, known as the latent heat of vaporisation, is what significantly lowers the air temperature.
How Evaporative Cooling Works
At its core, evaporative cooling mimics the refreshing feeling of a breeze over water. When water transitions from a liquid to a vapor, it requires energy, which it pulls in the form of heat from its surroundings. This heat absorption is what makes the resulting air feel cooler.
We mentioned earlier there are a few important parts:
- a fan
- a water pump
- absorbent cooling pads
- a water tank or connection
The pump keeps the pads wet, and the fan draws outside air through them, initiating the cooling process. The cycle is continuous: the pump saturates the pads, the fan pulls hot air through them, the water evaporates and cools the air. The fan then circulates this fresh, cooled air throughout the home.
Evaporative Cooling in a Cost Effective Way to Cool Your Melbourne Home
Because ducted evaporative cooling systems only need to power a fan and a small pump, their energy consumption is dramatically lower – often up to 75% less – than refrigerated air conditioning systems. Why? Refrigerated cooling must run a power hungry compressor.
Installation costs are often lower than ducted air conditioning (even with the current VEU rebates), and the real savings accumulate over time. Lower daily running costs lead to a significantly reduced total cost of ownership throughout the cooling system’s lifespan.
If you service your evaporative cooling system before summer each year, it should last you decades. The lifespan of refrigerated air conditioning is around 10-15 years. We compare this further in our post on evaporative cooling vs air conditioning.
The Key Benefits of Evaporative Cooling Are More Than Just Savings
The advantages extend far beyond lower electricity bills, encompassing environmental and health benefits.
Lower Carbon Footprint
Using much less electricity means it creates a smaller carbon footprint. This makes it a good choice for homeowners who care about the environment.
No Harmful Refrigerants or Greenhouse Gases
Traditional air conditioners use refrigerant gas. These can be strong greenhouse gases. Evaporative cooling uses only water instead. This eliminates the risk of releasing harmful chemicals into the atmosphere.
Continuous Air Changes Per Hour and Ventilation
Evaporative systems constantly draw in 100% fresh, outside air. This air is filtered through the wet pads, providing excellent ventilation and improving indoor air quality compared to the recirculated air of standard refrigerated air conditioning units.
Doors and Windows Can Remain Open
For the system to work effectively, windows or doors must be left slightly open to allow the humid, cooled air to exhaust. This creates a pleasant, breezy environment rather than a sealed, stuffy one.
Climate Suitability is Important to Consider
While highly effective, installing an evaporative cooler is not a one-size-fits-all solution.
The system’s cooling capacity is directly tied to the evaporation rate, which is highest in low-humidity environments. In dry climates, it can lower air temperatures significantly, but if you live in a humid area (down near Williamstown or Altona for example) reverse cycle technology would be the better option for you.
According to Sustainability Victoria, Melbourne’s average humidity in summer is between 40-50%, which is why evaporative cooling has long been installed alongside gas ducted heating in Melbourne.
Evaporative cooling uses water, something to consider in arid regions. However, the amount is often modest compared to the electricity needed to run central air conditioning systems.
20 Years
Experience
Professional
and Licensed
24 Hour
response time
Parts and labour
Guaranteed
Residential
& Commercial
Service
Melbourne Wide
No hidden
Cost
Clean Installation
Service
