Described is a large, thin frame gas cooled electric generator for power generation, having a gas cooled rotor arranged along a centerline of the generator; a gas cooled core arranged coaxially and surrounding the rotor; a plurality of coils arranged within the core; a support frame arranged to fixedly support the core and rotationally support the rotor; a gas cooling system that circulates a cooling gas within the generator; a pressurizing system that variably pressurizes the cooling medium to a maximum pressure of one bar relative to atmospheric pressure; and a pressure boundary member that surrounds a plurality of the rotor and an entirety of the core and stator windings, the frame configured to operatively contain an internal cooling medium pressure of 2 bar relative to atmospheric pressure.