ON average Your car Air Conditioning is about 5 Tons (60,000 BTU) at highway speeds.
Yes sixty-THOUSAND BTU, not a typo. The compressor has to operate at a variety of speeds, from idle to redline, and a wildly wide range of thermal load, and temperature.
for more details find out the part no of compressor & search the specs over google. then convert kw
at avg 3- 5 hp is drawn by the ac compressor.