Let’s simply state what the First Law of Thermodynamics is. From Wiki:
First law of thermodynamics: When energy passes, as work, as heat, or with matter, into or out from a system, its internal energy changes in accord with the law of conservation of energy. Equivalently, perpetual motion machines of the first kind are impossible.
So whether you’re talking of a steel shell around a heated sphere, or a gas around a planet, or a component of a gas around a planet, ask yourself the question:
“Does it pass energy as work, heat, or with matter, into the sphere or planet?“
Consider the passive steel shell around the internally heated sphere, the so-called steel greenhouse.
1. Does the passive steel shell do work on the sphere? No, it doesn’t touch the sphere, or at most, simply rests upon the sphere’s surface.
2. Does the passive steel shell send heat to the sphere? No, it’s passive firstly, and secondly, it’s cooler. It has no heat to send to the sphere. Therefore, it sends no heat to the sphere.
3. Does the passive steel shell pass matter into the sphere? No, there’s no exchange of matter.
Therefore, the shell does not cause the sphere to heat up beyond the heat input that the sphere is internally provided. QED.
The same goes for a gas around a planet, in the context of the sophistically-named “radiative greenhouse effect” of climate pseudoscience.
The First Law of Thermodynamics is all you need to debunk climate alarm, and its sophistical greenhouse effect.
Comical, really.