That needs to be put into your calculations too.

- Jake

If you only spend 20 minutes of the rest of your life on economics, go spend them here.

Then you moved the goalposts rather far from supplying electricity to the Ruhr area industry :-)

electrifying nearly all energy use

As JakeS said, such electrifying can improve energy efficiency greatly, lowering the generating capacity needed. I add that solar thermal (which is spreading rapidly in Germany) and geothermal (which I see as significant by 2030) can give heat energy without electrifying.

Yield per-square-of panel is not the same as yield per - square of plant.

Correct, you need North-South separation (for Sun-following plants, East-West too). However, just because that, not all the surface you contemplated is 'covered'. For rooftop plants, separation is provided by North-facing roof sides, courtyards, gardens and streets (the latter also for plants installed on highway noise barriers).

_{*Lunatic*, n.
One whose delusions are out of fashion.}