How Much Electricity Does an 18,000 BTU Air Conditioner Use?
Real-world numbers for a typical Thai household running an 18,000 BTU AC, plus a quick formula you can use for any unit.
By เจิดพงษ์ มากกูล1 min read

An 18,000 BTU split-type air conditioner draws roughly 1,600–2,000 watts at full load. In real use the average over an hour is lower because inverters reduce power once the room is cool.
The simple formula
For an inverter unit averaging 1,400 W:
Inverter vs non-inverter
A non-inverter 18,000 BTU runs at full draw the entire time — expect 30–40% higher bills compared to a comparable inverter model.
Three quick savings
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