I would argue that the steam and even combustion engine are much easier to build than a solar panel, if you know how.
If he was given detailed instructions, I believe a mediaeval blacksmith could have build a steam engine. As soon as we go to 17th/18th century, we can probably build a combustion engine. Sure, it will be a bad engine, but it will do the job of burning refined oil and spinning.
But a solar panel? You need clean rooms, which need air purification, you need working knowledge of semiconductor manufacturing. Much harder than a solar thermal steam engine and a few lead or zinc batteries.
I would argue that the steam and even combustion engine are much easier to build than a solar panel, if you know how.
If he was given detailed instructions, I believe a mediaeval blacksmith could have build a steam engine. As soon as we go to 17th/18th century, we can probably build a combustion engine. Sure, it will be a bad engine, but it will do the job of burning refined oil and spinning.
But a solar panel? You need clean rooms, which need air purification, you need working knowledge of semiconductor manufacturing. Much harder than a solar thermal steam engine and a few lead or zinc batteries.
Mad Max would be a lot different using those first primitive engines instead of the V8 and whatnot.