> (china is provably much more cost efficient at doing large projects than anyone else albeit at a high human cost)
Tesla and SpaceX is proving that with the right leadership, western countries can also do large projects. Anyway, I think we should let international corporations compete for such projects, kind of like ship construction or more remotely, the car industry.
> Ending the day with half of that production in a battery nets you an LCOE around $50 and that is falling by 15%/year with little indication of slowing down.
That is great, and I'm a huge believer in solar for many purposes in suitable climates. Where I live, though, we have about 4-6 hours of faint daylight in the middle of winter, when it's really cold.
Also, unlike nuclear, no country has so far been able to demonstrate an electrical grid that is powered exclusively by renewables (and Europe has tried). So far, everyone who tried, ended up with a huge reliance on (mostly Russian) natural gas, while having prices quite a bit above $50/MWH LCOE (for the grid as a hole). Currently, consumer facing prices are above $500/MWH, and may reach $1000/MWH this winter.
If some country wants to invest in a plan to make them independent of natural gas without nuclear, I wish them the best of luck, but in my opinion, nuclear is the proven path. Also, it's not like one cannot do both at the same time.
> Wind is a similar story (although not dropping as precipitously) and moderately anti-correlated.
Wind also has longer variance in supply. To some extent, making a grid the size of Australia may lower the variance, but at the cost of a grid that competes with nuclear in zero day investment costs while bringing its own set of political risks (especially in places where the grid needs to span many countries with different cultures).
> spend it on a new system that is $3/MWh
With all due respect, this is a fantasy number. When you're not including the storage and/or distribution needed to provide stable supply, this number means nothing. (Or rather, it's only relevant as long as only a small fraction of the power comes from such a source.)
Actual costs (LCOE, including enough enough storage to provide stable supply) are much higher. Different estimates exist. Your $50/MWh is probably the lowest I've seen. Typically I see $100-$200/MWH when including moderate storage, and several times that (up to $1000/MWH) when including enough storage to last several days with very little wind.
From my point of view, paying $30-$50/MWH for stable electricity production, with the lowest carbon emissions (construction emissions for concrete, etc, are about the same as the best renewables), low dependence on minerals that are in short supply (rare earths, etc) using proven technology is quite fair.
Hopefully, renewables, thorium, fusion etc will continue to develop to a point where they become clearly superior to nuclear in terms of price. But if so, I see that as a potential upside. Building more nuclear provides a hedge against the risk that this will take a long time.
> And then there's all the geopolitical problems going nuclear entails for the large portion of the world who aren't allowed to make their own fuel.
It's not for every country, but unlike natural gas, there are enough deposits in stable democratic western countries to power all such countries.
Also, there are alternatives sources for China and Russia to not worry too much about the risk either. India, being somewhat in-between these worlds would probably be able to source fuel from at least one.
And unlike natural gas, transporting nuclear fuel is quite trivial, due to the energy density.
Finally, it's not like we need to have 100% of one source of energy. Some should probably go mostly renewable (Australia, for example), due to climate. Some already have plenty of hydro, and some would benefit from having more (or much more) nuclear.
Some might also need to go for fossil fuels, at least as backup. I'm thinking of smaller islands, for instance (like Hawaii). But it would be good if we could soon start to REDUCE the dependence on fossil fuels, instead of consuming more and more every year, globally.