Learn About Portable Air-Conditioners

There are two types of portable air-conditioners:

1. Coolzy – provides micro-climate around people who need cooling. Coolzy is easy to carry and move where you need cooling.  Coolzy is quiet, ideal for sleeping, provides almost instant cooling in a minute or so, and is the lowest cost cooling solution overall at about $390 annual cost.

2. Old-style portable air-conditioners that claim to cool the whole room, with a large exhaust pipe attached to a window. Unfortunately, pumping hot air through the pipe heats the room and causes hot outside air to be sucked into the room through openings. As a result, the room cooling after 30 minutes is only 3 – 4 °C (5 – 7 °F), even with a large and powerful machine. Because of the high electricity consumption, the annual cost is about $650. Learn more here.

Old-style portable air-conditioners are too noisy for most people to sleep comfortably. They are not really portable at all. They are large and heavy and can only be carried with someone else to help.

Coolzy provides more intense cooling than an old-style portable air-conditioner: learn more here.


Where does Coolzy’s waste heat go?

Coolzy has no exhaust pipe. Coolzy uses so little electricity that it does not need one.

Coolzy directs its warm air exhaust to the ceiling where the heat is absorbed, just like the warm air from your fridge which you don’t notice (warm air rises naturally). Any excess finds its way out of open windows or doors.

A Coolzy releases only 340 Watts, similar to three people in the room. So, in larger rooms, Coolzy will not warm the room much at all.

In a small room, especially if it is well-insulated, Coolzy will create some warming in the upper part of the room. With good ventilation from open window or doorway, this will not be perceptible to people using Coolzy.

Later in 2022, we will release a new accessory for Coolzy soon to help remove unwanted warm air. Watch this space.

Use a fan to improve room ventilation if needed. Learn how to use a fan to provide extra ventilation for a small room.


Coolzy: 55 cm high x 29 cm x 39 cm, 17.5 kg, easy to carry.

Old Style Portable: typically 80 cm high x 40 cm x 45 cm, 32 kg, hard to move.

In moderately hot weather, Coolzy can be used on its own (as shown) or with a normal mosquito net. We recommend the optional Igloo bed tent in really hot conditions with indoor temperatures consistently over 28°C at night. The tent amplifies cooling over the bed and can also reduce energy consumption by about 30-40% which is ideal for battery and off-grid applications.

Old style portables are unsuitable for bedrooms. They are much noisier and have relatively low cooling performance compared with a split AC using the same power. Also humidity builds up in room with time.

Coolzy: use it anywhere because there is no exhaust hose

Old-style Portable: has to be close to a window to attach the large exhaust hose with the window kit

Coolzy: With a monthly running cost only about Rs 2,500 you will soon save the entire purchase cost

Old-style Portable: Monthly running cost at least Rs 10,000 (12 hours a day)

Coolzy: 800 – 1,100 Watts cooling, 300 Watts electricity (same as a few iridescent light bulbs), 0.25 tonnes CO2 over three years, equivalent to 110 litres of petrol

Old-style Portable: 3,000 – 7,500 Watts cooling, 1,000 – 2,400 Watts electricity, 1 – 2 tonnes CO2 over three years, equivalent to 450 – 900 litres of petrol.

Coolzy: all cooling directed around people using it

Old-style Portable: mixes air in room, sucks out more air than it cools and sucks in hot air from the roof space outside. Very little room cooling.

Click here for more details

Coolzy: 47 – 54 dB – quiet, like an electric fan

Old-style Portable: 55 – 63 dB – noisy, can be hard to hear people speak

Coolzy: Open

Old-style Portable: Closed

Coolzy has eliminated the exhaust hose: such a wonderful improvement. It is on caster wheels and can easily be moved where you want to use it. At 17 Kg it is easily carried too. Take it anywhere you need cooling, even outside in sheltered places.

The old-style portable comes with a hose and window kit which is fiddly to install, and only works with some windows. That means you cannot easily move it once you have installed it. Plus the exhaust hose is ugly, helps to heat the room, and makes lots of noise.

Answer: Coolzy releases only 300 Watts, similar to three people in the room. Coolzy directs its warm air exhaust to the ceiling where the heat is absorbed, just like the warmth from your fridge which you don’t notice (warm air rises naturally). Any excess finds its way out of open windows or doors.

In a humid climate like Singapore, the warmth is actually useful because it makes the relative humidity slightly lower and reduces the tendency for mould to grow on walls and other surfaces.

Coolzy works in any room, even outside in sheltered places. It creates a micro-climate, a cool zone, up to 4-5 square metres.

If the temperature inside your bedroom regularly exceeds 28°C at night, the Igloo bed tent provides extra cooling to keep you comfortable, and also provides chemical-free mosquito protection.

We always recommend the Igloo tent for sleeping with Coolzy in Pakistan.

The Igloo bed tent can also reduce the air conditioner power consumption to about 220 Watts average in the monsoon season, a valuable saving.

The Igloo bed tent also provides an ideal place to work from home, or for your baby or small child to be cool and comfortable during the day time.

We recommend keeping Coolzy near you, no more than 2 metres away. with Coolzy-Go, we recommend our Focus Enhancer accessory which extends the range and optionally directs the cool air flow at a higher angle.

If you need to cool a crowded room for 2 – 3 hours, a split AC is effective. Split ACs provide no fresh air exchange and the doors and windows need to be closed to retain the cool air so carbon dioxide, volatile organic compounds and body odours build up with time.  Prolonged use of split ACs for sleeping can cause dry itchy eyes and skin irritation from dry air and the running cost can be very high.  Expect to pay Rs 80,000 or more and at least Rs 12,000 a month for electricity if you use it for sleeping and sometimes during the day.

Ceiling fans can be effective in moderate heat.

An electric fan on a table next to a window can draw outside air through the open window and blow it across a bed to provide effective cooling for sleeping. Make sure that there is one other open window or doorway tor air to escape.

Fans provide about 2 degrees of apparent cooling. (Coolzy provides up to 10 degrees of apparent cooling, sometimes more).

Evaporative coolers (using water) cost much less than an air conditioner to run and provide cooling in the dry summer heat. Unfortunately they are noisy and relatively ineffective in the monsoon season because the relative humidity is very high, around 75% – 80%. You can use Coolzy with your evaporative cooler.

Coolzy is an Australian and Singapore based start-up company founded in 2007. Inventor James Trevelyan created the concept after experiencing summer heat in Pakistan with intermittent electricity for air conditioning.  He refined the concept with a series of prototypes, assisted by our manufacturers in Taiwan.  Our first commercial models went on sale in India and Pakistan in 2016.