INTAKE REQ FOR AN ATLAS COPCO GA75

HI,I HAVE A DOOR OPEN IN ORDER TO GET FRESH AIR TO THE AIR COMPRESSOR UNIT.UNFORTUNATELY THE FRESH AIR COMES FROM AN AC UNIT. I WONDER HOW MUCH OF THE AC UNIT IS CONSUMED BY THE AIR COMPRESSOR. SUCH AMOUNT OF ENERGY WILL JUSTIFY THE INSTALLATION OF A MAKE UP UNIT PLEASE ADVISE THE BEST PROCEDURE TO DETERMINE HOW MUCH MONEY I AM THROWING AWAY.THANKS IN ADVANCE RICK, NEW MEXICO