Maxwell's Demon Kitchen Friend

On their entrance to your kitchen, all molecules have their temperature measured, and depending on their kinetic energy are assigned either to the fridge or the cooker. Middling molecules are excluded, and passed directly into the waste disposal unit.

Thus efficient use is made of all molecules, no matter what their kinetic energy: active ones are used to heat, and sluggish ones to cool. This works because in any gas the molecules have a range of kinetic energies, and thus the individual molecules have a wide range of temperatures.

[I'm hoping for some quantum mechanical effect to toggle on and off the "R" in the final word of the title.]