Patent ID: 8001799

Claim:
An air-conditioning system for a vehicle comprising: multiple heat sources for performing cooling operation, one of which is an evaporator to which refrigerant compressed by a compressor is supplied, wherein the compressor is driven by an engine for driving the vehicle, and the other of which is a heat accumulator for storing the heat of the refrigerant; means for comparing a first input energy amount, which is an increased amount of fuel to be consumed by the engine necessary for generating a unit cooling capacity by the evaporator with a second input energy amount, which is an increased amount of fuel already consumed by the engine and which is necessary for generating the unit cooling capacity by the heat accumulator; and means for selecting one of the first and second input energy amounts, whichever is smaller than the other, for preferentially using such selected input energy amount in order to perform the cooling operation to control the temperature of the vehicle inside air.