Your author probably has many opinions that are best termed “minority opinions.” That is, these are not shared with the opinions of the main incumbent experts in a particular field. These include the intersection of nuclear-electric generation and renewable power generation. I consider nuclear-power a renewable form of generation, mainly because (1) there is no shortage of Uranium used as the active component in fuel, (2) although Natural uranium consists of 99.3% U238 and 0.7% U325, and the latter is the only type usable for active-fuel in nuclear reactors, U238 can be “bred” into plutonium which is also usable for active-fuel. Plutonium is usually extracted from spent nuclear-fuel, purified and used to enrich new fuel elements. This process is much more complex than described in the last sentence, but there is no risk of running out of active reactor-fuel within the next few-centuries-to-millennia, which would be my definition of “renewable”.
