Quick answer: A ton of refrigeration is 12,000 BTU/h (about 3.517 kW), so a typical 1.5-ton split AC is 18,000 BTU/h = 5.2752793 kW of cooling.
How it's calculated
The power is changed to watts, then to your unit. One mechanical horsepower is 550 foot-pounds per second, 745.7 W; the metric horsepower (PS, used by many European and Asian car makers) is 735.5 W.
Air conditioners in the Gulf are sold by tons or BTU/h of cooling: 1 ton = 12,000 BTU/h = 3.517 kW of heat removed. This is cooling output, not the electricity the unit draws, which is lower by the unit's efficiency (EER or COP). To size a unit for a room see the AC BTU calculator.
Worked examples
- A 1.5-ton AC: 18,000 BTU/h = 5.2752793 kW
- A 150 kW car engine: 150 kW = 201.15331 hp
- A 200 PS engine: 200 PS = 147.09975 kW
Common power conversions
| From | To |
|---|---|
| 1 hp | 0.74569987 kW |
| 1 kW | 1.3410221 hp |
| 1 PS | 0.73549875 kW |
| 1 TR | 12,000 BTU/h |
| 1 TR | 3.5168528 kW |
| 12,000 BTU/h | 3.5168528 kW |
| 18,000 BTU/h | 5.2752793 kW |
| 24,000 BTU/h | 7.0337057 kW |
| 1 kW | 3,412.1416 BTU/h |
| 100 kW | 135.96216 PS |
Frequently asked questions
How many kW is one horsepower?
One mechanical horsepower is 0.7457 kW; one metric horsepower (PS) is 0.7355 kW.
How many BTU is a 1-ton AC?
12,000 BTU per hour, which is about 3.52 kW of cooling.
Is BTU/h the same as electricity use?
No. BTU/h on an AC is the cooling it delivers. Its electrical input in watts is that figure divided by its energy efficiency ratio (EER).
How do I convert kW to tons of cooling?
Divide by 3.517. A unit putting out 7 kW of cooling is about a 2-ton AC, or 24,000 BTU/h.
Is PS the same as hp?
Nearly, but not quite. A metric horsepower (PS) is 735.5 W and a mechanical one is 745.7 W, so a 100 PS engine is about 98.6 hp.
How many kW is a kVA?
That depends on the power factor: kW is kVA times the power factor. A 10 kVA generator at a power factor of 0.8 gives you 8 kW.