You can pedantically point out that nuclear isn't truly unlimited. But once you're getting to the point of energy sources lasting millions of years, the term "renewable" becomes academic. You could just as easily point out that the sun will eventually run out of hydrogen.
1. https://en.wikipedia.org/wiki/Life-cycle_greenhouse_gas_emis...
2. https://www.forbes.com/sites/jamesconca/2016/07/01/uranium-s...
Source: https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2051332
Uranium's incredible energy density means increases in raw uranium costs is negligible (enrichment is a much more expensive part of the overall nuclear fuel cost). From the previously linked article:
> Over the last twenty years, uranium spot prices have varied between $10 and $120/lb of U3O8, mainly from changes in the availability of weapons-grade uranium to blend down to make reactor fuel.
> So as the cost of extracting uranium from seawater falls to below $100/lb, it will become a commercially viable alternative to mining new uranium ore. But even at $200/lb of U3O8, it doesn’t add more than a small fraction of a cent per kWh to the cost of nuclear power.
Uranium isn't recyclable: there is no satisfactorily running fast-breeder.
My point was not about costs but about emissions. Extraction and immediate post-processing (before enrichment), and therefore ore grade, have a major impact on emissions: see figure 5 in the referenced communication (Werner, Heath).
Seawater: "pumping the seawater to extract this uranium would need more energy than what could be produced with the recuperated uranium" Source: http://large.stanford.edu/courses/2017/ph241/jones-j2/docs/e...
Uranium recycling is not the same thing as breeder reactors. It's essentially the same nuclear enrichment we do to natural uranium to bring it up to concentrations of U235 as usable fuel, just used on spent fuel rather than virgin uranium.
Also, for uranium sea water extraction the plan is to drop buoys with the absorbtion material and let natural currents bring water into contact with it. Pumping all that water out of the ocean would of course be stupid.
Recycling: however breeders are AFAIK the most efficient way to tackle this (however it is so difficult there is no adequate industrial reactor, after ~70 years of prototypes and research). Other ways don't seem very appealing, for example France ceased to recycle in 2013.
Yes, since the 1980's a fair amount of Grand Plans aimed a extracting uranium from seawater. Nothing industrial yet. I won't hold my breadth.
> This is flat out wrong.
No, it's not: https://news.ycombinator.com/item?id=26673987 and https://news.ycombinator.com/item?id=26603464.
Indeed, and neither are solar, wind, hydro or any other - they all have environmental impact for producing the panels, turbines, dams, etc. So there are actually no exceptions at all, anywhere, which makes the classification completely useless. Could we get back to the topic now?
This is flat out wrong. Containing, mining, recycling and long term storage are so extremely costly and energy hungry that it does not make any economically sense in mid term to use nuclear power. And do not forget. Nuclear is not renewable. It has to be mined. There are mines which will be empty sooner than generally expected. And any kind of mass produced „nuclear battery“ which will eventually end up in land fill is a risk not worth taking. It reminds me of the story about leaded fuel. Yeah maybe a few cars are no problem. But scale up the pollution and boy will you be in trouble.