What to know before buying portable cooling
Check whether it is compressor or evaporative
Compressor portable ACs produce hot exhaust air that must vent outside via a hose. Evaporative and mini air coolers usually do not need a hose, but they cool less aggressively and work best as close-range personal cooling.
Single-hose vs dual-hose
This only applies to compressor portable ACs. Single-hose units are simpler to set up. Dual-hose models are slightly more efficient because they draw in outside air for cooling rather than recirculating room air. For most UK homes, a single-hose model is fine.
What size room will it cool?
Compressor portable ACs are typically rated in BTU. A general guide:
| BTU Rating | Room Size |
|---|---|
| 7,000–8,000 BTU | Up to ~15m² |
| 9,000–10,000 BTU | 15–22m² |
| 12,000+ BTU | 22–30m² |
Running costs
A typical compressor portable AC draws 700–1,200W. Smaller evaporative coolers can be much lower, sometimes around 50–80W. At average UK electricity rates (~28p/kWh), running an 800W compressor unit for 8 hours costs around £1.79; a 55W evaporative cooler costs around 12p for the same period.
Portable cooling FAQ
Is an evaporative air cooler the same as an air conditioner?
No. A compressor air conditioner actively removes heat from the room and vents it outside. An evaporative cooler uses water evaporation and airflow, so it is better for close-range comfort than full-room cooling.
Do portable air conditioners use a lot of electricity?
Compressor portable AC units often use around 700–1,200W. Smaller evaporative coolers may use much less. Use the running cost calculator to compare products.
Do I need a window kit?
You need a window or vent kit for compressor portable AC units with an exhaust hose. Mini and evaporative coolers usually do not need a hose.