Humans can’t convert sun energy into biological energy. We aren’t plants.

However we eat plants and we eat the things that eat plants. So do you consider plants and animals part of your environment or not?

Is the basic requirements for having an economy being a set of humans in a society that has language and culture and exchange?

There’s no free lunch

Human activity takes from the non-human environment.

Under an abstracted society which you could call capitalism if you like these resource extractions are done with no view to externalities and we know this because even in a basic undergraduate economics degree you will be told companies do not price externalities and there are no pricing mechanisms for externalities outside of Reactionary measures historically

Again I’ll reference here the entire history of ecology and cybernetics has tried to make this abundantly clear that these are all connected and the fact that you seem befuddled about these connections tells me everything I need to know about this conversation

In your opinion which society / nation / government in human history is closest to your ideal of how things should be?