Abstract: A system for and method of rotating a transfer wheel providing heat and/or moisture exchange between two counter-flowing air streams. The system comprises: a frame; a transfer wheel including a transfer matrix mounted and rotationally secured relative to the frame so that the wheel can rotate through the two counter-flowing air streams and heat and/or moisture can be transferred between the two counter-flowing air streams; and a first plurality of motor components fixedly mounted relative to the wheel so that components of the first plurality function as a rotor of a motor, and a second plurality of motor components fixedly mounted relative to the frame so that components of the second plurality function as a stator of a motor; wherein power supplied to motor components of the second plurality causes the transfer wheel to rotate through the two counter-flowing air streams.