Thanks for the comment. I think you're probably right about the spectrum of storage costs and nuclear/renewable hybrids. That's something I hope to explore in future modeling work with a colleague here at MIT.
Just to be clear: as I noted in the intro sentance, this post is focused on nuclear in combination with variable renewables like wind and solar, not more reliable sources like hydro, geothermal, or biomass.
Also, while solar better aligns with electricity demand than wind, that doesn't solve the integration issues with nuclear. If it reaches a penetration level where at mid-day, solar is producing close to 100% of load, nuclear will have to cycle off. Solar also is closer to peak, but not really on-peak. In nearly all regions, peak demand is experienced in late afternoon or early evening, not midday when solar systems are at 100%. So what we're seeing in some of the modeling around here (MIT) of high-penetration of solar is that the remainder of your system (i.e. excluding solar) becomes a "double peaking" system: you get a peak in late morning, then a big trough as solar ramps up around midday, then another sharper peak in the afternoon/evening as solar falls off and peak demand picks up. That actually increases rather than decreases the need for fast-ramping system capabilities. California regulators have dubbed this the "Duck Curve," while Jeff St. John calls the even more pronounced situation in Hawaii the "Nessy Curve" (both for their shapes).