I was about to post a similar sentiment. I allowed it since the thought experiment expressed that there is no current knowledge, and you don't get to fission without going through the industrial revolution (extreme temperatures, quality of metals, support services required by a stable/advanced society).
However, the author goes into quite a bit of detail about the validity of photo-voltaic panels, having obviously done some research into how solar panels work, life-expectancy, manufacturing. It's for this reason why I'm wondering why fission wasn't researched.
Nuclear is carbon-neutral, it's about 1000x the energy density of combustion, have lifetimes of several generations, and (at least in the States) have security measures that would make it resilient to "post-apocalyptic" scenarios. It seems ripe for this kind of thought-experiment.
If all conventional power was replaced with the current technology used in most nuclear power plants we would be out of fissionable material within a year. I'm not sure how long it would last if we use breeder reactors though...
I think you mean fissile instead of fissionable [1]. Current reactor technologies consume a very small fraction of fissionable material. Reactors discharge nearly as much fissionable material as they take in. And the lifetime of uranium resource is highly dependent on the price you are willing to pay. Seawater contains enough uranium to supply all reactors in the world at current consumption rates for ~60,000 years [2] estimated to only be about 8x the current spot price [3]. Using fast reactor technology that has already been developed and researched heavily could also stretch the resource by another factor of 100X or more.
While nuclear fission is an important component of our power-generating technology, it's a hard to see an 18th century society developing it as a solution to a shortage of charcoal.
No nuclear energy technologies get a mention in the article which seems like a strange omission.