>>13730100You are a wizard. You want to create a system in within a vacuum chamber that is at 0K.
Normally, you have to supply the entire internal energy: that is, the heat energy and the work required to hold the thing together. However, let's say that you create your system in a chamber with an atmosphere - a gas, so to speak. That way, whatever you're creating within your system is mechanically coupled to the gas. Now, if you want to create your system, you'll still need to supply the heat, but thanks to the mechanical coupling you no longer have to provide the work: the atmosphere within your chamber does that for you.
So, the energy you need to provide is no longer the full internal energy: it's the enthalpy. You're basically getting a discount in energy costs.
