Btw, further to my other reply here, don't fall into the same doomer trap as Indi (bless his heart) and "B", there is no shortage of copper or anything else needed for a solar hydrogen ecology.
Trust me I am a long practicing, well accomplished Systems Engineer, availability of materials is something we take into account very early in any analysis.
The trouble with Indi, and B, and all the other doomers, is that they are looking for proof we are doomed, when there is none.
But there is plenty of proof showing we are not doomed, but actually at birth into a new era, of being an adult species, finally adding value to our mother host, Earth, paying back our energy debt to it / her many times over.
Dooming, risks being a self fulfilling prophecy.
If we believe we are doomed, to even just carrying on with the fossil fueled destruction, then we will be dooming ourselves for sure.
To me the dooming of B, not Indi, looks like the typical things an investor lamenting the demise of investing in fossil fuels might say, actually almost exactly what the banks would like us all to believe, so that we keep doing what they need us to, to maintain their profits, just deposit all your money in their safe hands, then do us all a favor and just go and die.
Notice how Switzerland is full of Swiss banks with exactly this business model.
I even accused B once, of representing banks behind the pseudonym, and he banned me from accessing his / her stories.
Indi should choose his buddies and mentors more wisely, it seems to me, though I love his style of writing, he was and maybe still is misguided by B, and other investor doomers, in my opinion.