Abstract: An air intake unit, a compressor drawing atmospheric air through the air intake unit into the compressor unit, a cooling unit which cools the compressed air, a filter unit which filters the cooled air, a gas separator which separates the filtered air, a separated gas outlet which receives the separated gas, and a heat exchange apparatus comprising a body having a first fluid inlet and outlet, a second fluid inlet and outlet, a first fluid conduit between the first fluid inlet and outlet, and a second fluid conduit between the second fluid inlet and outlet. The heat exchange apparatus allows heat exchange between conduits and is arranged to receive compressed atmospheric air at the first fluid inlet and supply it from the first fluid outlet to the cooling unit, and receive filtered air at the second fluid inlet and supply it from the second fluid outlet to the gas separator.

Abstract: A gas intake unit, a compressor unit, a gas separator, a separated gas outlet, and a pressure control apparatus. The compressor unit draws gas through the gas intake unit and into the compressor unit. The gas separator separates the compressed gas from the compressor unit. The separated gas outlet receives the separated compressed gas from the gas separator. The pressure control apparatus controls the pressure in the gas generation apparatus between the compressor unit and the gas separator. The pressure control apparatus comprises a body portion having a fluid inlet and a fluid outlet, a pressure sensor module, a valve module, and a control module. The pressure sensor module measures the pressure of fluid in the body portion. The valve module controls the flow of fluid out of the fluid outlet. The control module receives an output signal from the pressure sensor module and operates the valve module.