> Yes, everything says that it's possible to create safer nuclear reactors. But our current ones aren't.

1) extraordinary claim
2) completely miss the point that the 10000 bureaucratic safety rules could be trimed by half while actually improving security and reducing costs.
3) completely miss the point that current models from Russia and China are cost effective and comply with aforementioned unoptimized rules.

> remove the safeguards, and they won't be safe anymore

most of the reactors from the 70s and 80s are still in use. they have much less safeguards and are still safe enough as in you'd better invest the saved money in saving lifes/medecine research than in those hypothethical safety gains that only drive marketing and hypocrisy.

> Adding nuclear capacity will increase the nuclear operational cost even more than renewables (because they have the same generation profile).

completely miss the point that not developing renewable and going for 100% nuclear increase overall economics.
completely miss the point that nuclear plants can contrary to renewable decrease their output in a very fine grained way. Why is that interesting? The plant cost almost the same, but does not add a significant cost by overproducing electricity. When renewable overproduce electricity (which happens all the time given enough share) the excess electricity will break the electric grid and cause a nationwide shutdown. To prevent that, the Grid operator has to sell electricity at a loss (AKA pay people to consume the electricity). Given some level this startegy won't even work and will need a special costly infrastructure optimized for burning (throwing away) excess electricity.

> But we know it's way longer than that

who is we? Where is the evidence?
Also newer reactors have a lifespan extendable to 100 years hence you need to triple or quadruple the price.
And wind, which is generally much more prevalent than solar last in most cases 20 years. In 2016 they have started (in germany) installing twice as big turbines which are likely to have shorter lifespans.

> The only solution here is storage.
> Well, eventually we will need storage. That's true for nuclear too.

nuclear doesn't need energy storage.

> Storage seems to be viable even with current tech (not using batteries)

please source, enligthen me, I am unable to find reliable information supporting this.

> Anyway, natural gas generation at night is a pretty good stop-gap

Please let's not be a joke, the discussion is about a long term fossil-free future. Not a thesis that only works until it doesn't.

> grid storage to use lithium at all

wtf, energy storage without batteries is niche. What are you refering to? Water, hydrogen? The majority should be with electric batteries AKA lithium. This should be obvious.

> renewables don't increase the consumption of fossil fuel based sources in any way

Renewable needs pilotable energies. Solar in january and december is almost non existent. How much is an empirical and country dependent question but bewteen 20-30% average share of fossil energy needed seems probable. Meanwhile 100% nuclear is perfectly doable. 70% renewable 30% nuclear is also doable but would be economically inefficient.

> both solar and coal are normally built by private business with proper accounting in practice to compare their costs

Wrong assumption, solar and wind in germany are extensively subsidized.

Anyway the most salient point about this discussion is the storage energy cost and feasability, of which you provide zero data.

regarding lithium availability:
https://www.reddit.com/r/AskScienceDiscussion/comments/q78xv...
Enough to build 8 billions cars and then zero cars for the next generation LOL.
Now add that in addition of one car per habitant we need a similar or even bigger battery for his regular electricity uses, including house heating.

Doing policies that last for just the current generation and not the next centuries is madness.
Yes we've all heard there are HUGE reserves in the oceans. Which pointless to say. There are a looot of gold in the oceans too. The density and extractability of it is the key question. The fact this is not currently used means it cost more than current methods. How much more? x10 ? x100? x10000? Who knows? Sharing technical evidence about this issues would improve the depth of the discussion but until then we are manipulating a huge existential risk.

about uranium reserves:
right, the current estimate of reserves is of a 230 year supply at current consumption. The needed consumption for 100% would be at least a x10 so let's say we ran out of uranium in 23 years if massively adopted.
1) A major point is that contrary to lithium, the mining industry of uranium is much smaller and therefore if it received mass funding, the reserves might significantly increase.
2) like lithium there are huge oceanic reserves and like lithium, this is not a solution until proven otherwise.
3) reactors that reuse MOX fuel (like e.g. France does) can significantly (how much ?) reduce uranium consumption. Note that lithium can be recycled too but setting a global systematic recycling industry is yet to be done.
4) Indeed thorium reactors (not uranium) are the ideal solution since we have thorium for the next millenium. Thoriums reactors are not just a theoretical concepts, some have been made so it is feasable. It has not been developed because the energy efficiency/economics are inferior (how much ?) although since most of the cost is on the time to build the plant anyway, this should still be a viable solution although not necessarily as cost effective as renewable here (but with an expensive energy storage grid and pragmatic designs (like russian/chinese ones) and taking into account lifespan, and renewable need for fossil fuels/gaz, it very well could be)
As for the ocean argument it seems easier to solve for uranium though which is needed in much less quantity (because of its ernergy density) and hence needs less regional density.
Note however that water filtration methods for lithium are often similar to existing desalinisation plants. Which ironically are a great specialization for nuclear power plants.