I joined this group few days ago (and I’m a bit disappointed by the lake of activities but your recent messages motivated me). I’m not a "tech guy », I’m just a interaction designer so I won’t be as specific as some messages. But your conversation about the web and « renewable energy » and the « drawback » of their intermittency, reminded me a project (it’s more like an experiment) I seen some weeks ago, it’s a bit specific and anecdotic but I hope this will give you some input of a very practical case about this topic : https://www.lowtechmagazine.com/2018/09/how-to-build-a-lowtech-website.html

In short, it’s a website with a server powered by solar energy, there is a battery (12V 7Ah) and the point of the design is to by as efficient as possible (very few css, no custom font, using dithering, etc.) but in staying attractive and ergonomic.

The author of the blog also write an article about « how to build a low tech internet » giving some clue about what we are discussing : https://www.lowtechmagazine.com/2015/10/how-to-build-a-low-tech-internet.html