Our paper1 discussed the conditions for which a theoretical counterclockwise (ccw) and inherently irreversible cycle could be a refrigerator. We found three necessary and self-consistent criteria for refrigeration. One criterion required that all heat absorption occurred at temperatures below those at which heat was emitted. In addition we also speculated that refrigerators required two adiabatic segments, although by themselves adiabats were not a sufficient condition. Dr. Bizarro's Comment2 presents a ccw Stirling cycle as a counterexample to our findings.
We maintain that the ccw Stirling cycle cannot function as a viable refrigerator since it violates one of our criteria mentioned earlier, and has no adiabats. The Stirling cycle has two isotherms and two isochors, as pictured in Fig. 1. As we explain below, it is Bizarro's handling of the isothermal segments that is the primary source of an error that invalidates his analysis and conclusions. In Sec....
