I think the idea is to use energy input collected from the sun to push our material resources in a circle instead of the way we do it now, which is to use previ

I think the idea is to use energy input collected from the sun to push our material resources in a circle instead of the way we do it now, which is to use previously stored sun energy to push our natural resources in a line from a more useful place/form to a less useful place/form. This linear method leaves us with both less useful material and less easily collected energy when we're done. We will have to change over sooner or later and it gets harder if we wait until later. The thermodynamics of it is simple. The energy input of a nearby star means its not a "closed system". There's plenty of energy input to keep it all going. How to use it is the choice. Eventually the costs of idealistic schemes will balance out, probably with interest, at the point where there is no longer a choice; the stored energy collected and spent, and our material wealth buried in landfills after being reduced to its least useful form.