A fluid compression system, comprising: a hermetically-sealed housing having a rotatable shaft arranged therein, the hermetically-sealed housing defining a plurality of internal cooling passages (150a, 150b, 152a, 152b) and the rotatable shaft having a motor rotor section and a driven section, wherein the motor rotor section is adapted to rotate the driven section; a motor arranged within the hermetically-sealed housing, coupled to the motor rotor section of the rotatable shaft, and in fluid communication with at least one of the plurality of internal cooling passages; a compressor arranged within the hermetically-sealed housing and axially-spaced from the motor, the compressor being coupled to the driven section of the shaft and configured to receive and compress a process gas; a plurality of radial bearings arranged along the rotatable shaft and configured to support the motor rotor and driven sections, each radial bearing of the plurality of radial bearings being in fluid communication with at least one of the plurality of internal cooling passages; a blower arranged within the hermetically-sealed housing and coupled to a free end of the rotatable shaft, the blower being configured to circulate a cooling gas through the plurality of internal cooling passages to regulate the temperature of the motor and the plurality of radial bearings; and a gas-to-gas heat exchanger disposed downstream from and fluidly coupled to the blower, the gas-to-gas heat exchanger configured to receive the cooling gas from the blower and a flow of the process gas to reduce the temperature of the cooling gas, characterised in that the process gas is used as the cooling medium in the heat exchanger, and wherein the flow of the process gas is compressed process gas discharged from the compressor. a hermetically-sealed housing having a rotatable shaft arranged therein, the hermetically-sealed housing defining a plurality of internal cooling passages (150a, 150b, 152a, 152b) and the rotatable shaft having a motor rotor section and a driven section, wherein the motor rotor section is adapted to rotate the driven section; a motor arranged within the hermetically-sealed housing, coupled to the motor rotor section of the rotatable shaft, and in fluid communication with at least one of the plurality of internal cooling passages; a compressor arranged within the hermetically-sealed housing and axially-spaced from the motor, the compressor being coupled to the driven section of the shaft and configured to receive and compress a process gas; a plurality of radial bearings arranged along the rotatable shaft and configured to support the motor rotor and driven sections, each radial bearing of the plurality of radial bearings being in fluid communication with at least one of the plurality of internal cooling passages; a blower arranged within the hermetically-sealed housing and coupled to a free end of the rotatable shaft, the blower being configured to circulate a cooling gas through the plurality of internal cooling passages to regulate the temperature of the motor and the plurality of radial bearings; and a gas-to-gas heat exchanger disposed downstream from and fluidly coupled to the blower, the gas-to-gas heat exchanger configured to receive the cooling gas from the blower and a flow of the process gas to reduce the temperature of the cooling gas, characterised in that the process gas is used as the cooling medium in the heat exchanger, and wherein the flow of the process gas is compressed process gas discharged from the compressor.