The modern day automobile customers’ expectations are sky-high. The automotive manufacturers need to provide sophisticated, cost-effective comfort to stay in this competitive world. Air conditioning is one of the major features which provides a better comfort but also adds up to the increase in operating fuel cost of vehicle. According to the sources the efficiency of internal combustion engine is 30% and 70% of energy is wasted to atmosphere.The current Air conditioners in automobiles use Vapour compression system (VCS) which utilizes a portion of shaft power of the engine at its input; this in turn reduces the brake power output and increases the specific fuel consumption (SFC) of the engine. With the current depletion rate of fossil fuels, it is necessary to conserve the available resources and use it effectively which also contributes to maintain a good balance in greenhouse effect thus protecting the environment.This paper discusses about the study on implementing VAAcS (Vapour Absorption Air conditioning System) in automobiles using the waste heat from the engine exhaust which is generated in the process of fuel combustion, and then “dumped” into the environment even though it could still be reused for some useful and economic purpose. The use of vapour-absorption Air conditioning system for automobile air-conditioning can drastically cut down the shaft power and thus save the precious fuel and also provides better fuel consumption. Among various absorbent and refrigerant pairs used, Libr (Lithium Bromide) - Water is the most promising in this application due to high safety, high volatility ratio, high affinity, high stability and high latent heat.