Very nice article, thanks. It reminds me of "Renewable Energy - without the hot air" https://www.withouthotair.com/, by the late David MacKay; somewhere in the book he also depicted how much of the UK would have to be covered with solar panels to produce the country's electricity.

However, energy is one aspect, power is another; and there things get a bit more difficult when it comes to balancing power consumption and production, over a day or over a year. I did similar back-of-an-envelop calculations for wind energy: https://peter-wurmsdobler.medium.com/could-wind-farms-power-every-uk-home-by-2030-power-analysis-e920ff5b5ee2