The point is that while all these costs may seem eye watering & renewables do indeed not have that problem directly (they can have their own set of cost and ecological problems indirectly through requiring storage), they are actually comparatively tiny & it's only because fossil fuels externalize most of their cost that we don't have an easier baseline to compare against. There's varying estimates for how much climate change is costing us but some metrics have it at ~1T/year alone (not including all the healthcare costs associated with pollution from burning fossil fuels as those are even harder to estimate).
As for why I ignore Fukushima or Chernobyl, that's because for the next phase of scaling out nuclear, we shouldn't really be building LWRs. We should be building nuclear designs that fail safe (e.g. nuclear reactors). Even still, LWR designs being built today are much much safer than the designs used for Chernobyl and Fukushima. As for cost overruns and scandals, I can't really comment on them as I don't know any details except to say that cost overruns and scandals are not unique to large scale nuclear projects. Solar has it's own share of problems where grid operators are struggling with rooftop solar (see the political battle in California) & figuring out how to handle the variability of solar plants since we still don't really have scalable storage solutions (arguably maybe we should be mandating that some solar and wind plants have onsite storage to more accurately represent the cost of adding those renewables to the grid & is an externality frequently ignored when discussing the cost of solar/wind).
Don't get me wrong - solar & wind are great. If we can do more of it then great. I just think at a fundamental technological level it can't scale as quickly to replace fossil fuel dependency in the energy grid on any timescale that matters for us addressing global warming.
The cost is not relatively tiny, it's actually quite significant. Nuclear at least allows for better accountability & management of the waste it produces. Unfortunately accountability & management has been rather poor, diminishing the potential.
I am not entirely sure what your point is about reactor design. Did you mean we shouldn't build more BWRs? Agreed. If you mean we should focus on HWR like CANDU or experimental molten salt reactors, those have their downside. Deuterium is expensive & molten salt is corrosive & not commercially proven. If you really want nuclear you go with off the shelf proven designs like AP1000, but even then there are hurdles to build these as these boondoggle projects have shown. Yes every sector has scandal, but massive rate hikes & tens of billions in overruns is atypical & undermines the promise of what nuclear was sold as to those ratepayers.
Nuclear is go big or go home, and we can't socialize losses & liability while privatizing profit. Nuclear is also unattractive to the commercial market due to long-term ROI & project/liability risks. Effectively it needs to be a massive energy independence program funded by the government. I don't see that happening though.
As for why I ignore Fukushima or Chernobyl, that's because for the next phase of scaling out nuclear, we shouldn't really be building LWRs. We should be building nuclear designs that fail safe (e.g. nuclear reactors). Even still, LWR designs being built today are much much safer than the designs used for Chernobyl and Fukushima. As for cost overruns and scandals, I can't really comment on them as I don't know any details except to say that cost overruns and scandals are not unique to large scale nuclear projects. Solar has it's own share of problems where grid operators are struggling with rooftop solar (see the political battle in California) & figuring out how to handle the variability of solar plants since we still don't really have scalable storage solutions (arguably maybe we should be mandating that some solar and wind plants have onsite storage to more accurately represent the cost of adding those renewables to the grid & is an externality frequently ignored when discussing the cost of solar/wind).
Don't get me wrong - solar & wind are great. If we can do more of it then great. I just think at a fundamental technological level it can't scale as quickly to replace fossil fuel dependency in the energy grid on any timescale that matters for us addressing global warming.