The efficiency of a vapor compression system is increased by coupling the evaporator with either the intercooler of a two-stage vapor compression system or the compressor component. The refrigerant in the evaporator accepts heat from the compressor component or the refrigerant in the intercooler, heating the evaporator refrigerant. As pressure is directly related temperature, the low side pressure of the system increases, decreasing compressor work and increasing system efficiency. Additionally, as the heat from the compressor component or from the refrigerant in the intercooler is rejected to the refrigerant in the evaporator, the compressor is cooled, increasing the density and the mass flow rate of the refrigerant to further increase system efficiency.