Low-cost energy-efficient vehicle air conditioning system

An energy-efficient vehicle air conditioning system (10) includes a variable capacity refrigerant compressor (12) having a capacity control valve (17) with integral refrigerant sensors (142, 144) and control circuitry (228), and a driver interface panel (92) for selecting the discharge air temperature and inlet air source, and for selecting either a normal control mode or an energy-efficient control mode. When the energy-efficient control mode is selected, control setting indicators (118, 120) prompt the driver to request full-cold discharge air temperature and recirculated cabin air, and the control circuitry (228) initiates a compressor capacity control based on the refrigerant sensor information and a measure of the outside air temperature to produce a suitable discharge air temperature at a reduced power consumption level.