What's the difference between a portable air conditioner and an air cooler?

In the rush to secure the best cooling appliances during the UK's soaring temperatures, it's easy to end up buying something that doesn't quite work the way you expected. Whilst the best fans are fairly straightforward, there's a lot more confusion when it comes to the best portable air conditioners and air coolers – and importantly, they're not the same thing.

Whilst air conditioners and air coolers might sound like they do a similar job, they actually work very differently. The biggest distinction is that an air conditioner actively lowers the temperature of a room, whereas an air cooler mainly creates a cooler-feeling breeze.

Keep reading to find out exactly how they differ, and which one might be the better choice for you.

What's the difference between an air conditioner and an air cooler?

I've previously summarised the 3 reasons why everyone needs a portable air conditioner, but it's all to do with the way they work. A portable air conditioner uses a refrigerant and compressor to draw in warm air, cool it and push colder air back into the room. The unwanted heat is then expelled outside, usually through an exhaust hose positioned through a window. As a result, an air conditioner can reduce the temperature of a room, making it particularly effective during a heatwave.

That said, there are a few downsides. Portable air conditioners tend to be larger, louder and more expensive than air coolers, both in terms of the initial purchase price and running costs. You'll also need somewhere suitable to position the exhaust hose, which can make them a little more awkward to set up.

An air cooler, sometimes called an evaporative cooler, takes a much simpler approach. It draws warm air through water-soaked pads or a water reservoir, using evaporation to produce a cooler-feeling breeze before pushing it back into the room. Some models also allow you to add ice packs for an extra cooling boost.

However, an air cooler doesn't actively remove heat from the room in the same way an air conditioner does. It might make you feel noticeably cooler when you're sitting nearby, but you shouldn't expect it to dramatically bring down the temperature of an entire room.

Which is best?

It really depends on what you're looking for. Air coolers are generally cheaper to buy and run, and they're easier to move around. They're particularly useful in hot, dry conditions, although they can become less effective when humidity is already high because evaporative cooling adds moisture to the air.

If your priority is actually lowering the temperature of an entire room, a portable air conditioner is the clear winner. It'll cost more and require a little more setup, but it'll provide much more substantial cooling when temperatures really start to climb.

However, if you mainly want something affordable and easy to use that can provide a refreshing breeze without the installation or running costs of an air conditioner, an air cooler could make much more sense.