Air conditioning in the automobile has become an important area of research. The performance of an air conditioning system in an automobile depends upon three basic important factors such as compressor speed, evaporator load, and condensing temperature. How these factors when varied affects the COP of the system have been detailed in this review paper. Several performance studies on various refrigerants (R134a, R152a, CO2 and R1234yf) used in the automotive air conditioning system operating with various conditions revealed the better COP for R152a in comparison with R134a, whereas COP of R1234yf and CO2 was observed to be slightly lower than R134a. However, safety measures must be followed while using R152a due to its slightly flammable nature (ASHRAE A2 group). In this work, various alternative air conditioning systems used for automobiles have been presented in detail. Copyright © 2020 Inderscience Enterprises Ltd.