When you think about keeping cool inside a building on a hot day and the equipment that is used to achieve this, you’re most likely to think of traditional refrigerant air conditioning.

It’s what most of us have in our cars, it’s what is used in many offices and shops to keep temperatures down. However, air conditioning like this has only been around since the early 1900s. Before this time, a simple, yet effective method was utilised and is one still used is to this day.

A natural occurrence

Evaporative cooling is something that naturally occurs near waterfalls, streams, over lakes and oceans. For centuries the application of this natural process has been keeping people comfortable in the heat.
The origins of using this way of cooling can be traced back to ancient times. Examples of primitive evaporative cooling go back to the ancient Egyptians where slaves would fan jars of water to cool royalty. Other examples of using this and similar methods can be found in Indian, Iranian and Mexican historical paintings and texts.

Refining the technology

Over the years, the use of evaporative cooling has been refined for more commercial use. This commercialisation initially began in the USA at the very start of the twentieth century. It was during this time that the evaporative coolers we’re familiar with today, with pumps, valves and pads, were designed. Since then, the fundamental design of an evaporative cooler hasn’t changed a lot, which is largely down to the simplicity of the science behind how they work.

It is safe to say though that there as been a lot of fine-tuning since the first commercial design of an evaporative cooler. With better parts and controls, as well as the introduction of filtration, the modern-day evaporative cooler has come a long way from the early twentieth century. Since their early refinement, evaporative cooler units have been used across many different applications including cotton mills, print works and textile factories to name some of the first.

Over the years, there have been some less successful applications for evaporative coolers such as in cars, and in buildings housing swimming pools but we’re now in the position where we know the best use for this type of technology. What’s more, this technical understanding means that highly effective, large-scale evaporative cooling systems that involve numerous units and airflow manipulation have been designed and implemented thousands of times across the world. As such, factories, warehouses, gyms, large retail units and bakeries are all feeling the benefits of this proven, natural method.

Modern-day application

Over the last few years, there has been a resurgence in the popularity of evaporative cooling, with companies looking for an alternative to air conditioning. Many companies have been seeking to move away from refrigerant systems as they don’t fit with their carbon reduction targets.

Evaporative cooling is a greener, more cost-effective* solution thanks to its low energy usage, which makes it the perfect alternative for companies trying to be more environmentally friendly. It is a fresh air technology that doesn’t use recirculated air, which keeps oxygen levels high and means environmentally damaging refrigerant gasses aren’t used. What’s more, it is more effective than air conditioning for many applications such as warehouses and factories as open doors and windows have no adverse effect on performance and running costs. All this makes evaporative cooling the ideal solution for keeping down temperatures in large spaces, which is something with which traditional air conditioning struggles.

*Evaporative cooling costs typically 90% less than air conditioning in running costs and up to 50% less in capital spend

A tried and tested solution

Evaporative cooling in its most basic form has been keeping people, processes and products cool for centuries and continues to do so today. With more and more companies turning to this system of cooling, it’s clear that this is not a solution for the history books, it is a very relevant and successful method of cooling that is currently being used by millions of companies across the globe.


Watt J.R. (1986). History of Evaporative Cooling. In: Evaporative Air Conditioning Handbook [online]. Boston: Springer. [Viewed 27 March 2020]. Available from: https://link.springer.com/chapter/10.1007/978-1-4613-2259-7_2

AZEVAP., (2020). History of Evaporative Cooling Technology [online]. AZEVAP. [Viewed 27 March 2020]. Available from: https://slate.com/culture/2013/07/a-history-of-air-conditioning.html

Oremus, W., (2013). A History of Air Conditioning: From ancient mountains of snow to the window units of today. Slate. [Viewed 27 March 2020]. Available from: https://www.azevap.com/history-technology.php