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> first of being that at 70x current nuclear power we're going to reach peak uranium in 2 to 5 years.

Can you show your math?



https://web.archive.org/web/20090320104608if_/http://www.neu...

optimistic prediction at current usage pin peak uranium around 270yr without breeding.

now add 70x more reactor and that's that.

if we ever get to thorium breeders we get a chance of sustaining society for 120years, so 3-5 generation down the road.. and every year of 70x nuclear without breeders we lose a fifth of that.


This ignores many factors. Why are you assuming we won't reprocess fuel like France does? The CANDU reactors can already use Thorium. Why are you assuming we wouldn't have breeder reactors? If we ever actually ran the risk of running out of uranium, the price would rise and it would become viable to extract uranium from sea water - there is at least 4 billion tons of uranium in sea water.

If we derived all of our electricity from nuclear reactors, we would have enough fuel for at least tens of thousands of years (probably millions of years, but who knows how high electricity consumption will grow over the next few thousand years...) At any rate, by the time we would run out of uranium we likely would have mastered nuclear fusion.


lovely. presented with data the reaction is a fuckton "but what if"

well guess what the onus of proof is on you.


>... presented with data

Let's see... You take a report 16 years old and then you cherry pick the 270 number by ignoring all the other factors that wold be relevant if the world decided to get all of its energy from nuclear energy.

According to your link, you ignored reprocessing and using breeder reactors Relying on breeder reactors adds over another 8,000 years to the expected lifetime.

That 8,000 year number is conservative for several reasons:

Over time, we get more efficient use of nuclear fuel:

>...Over the years 1980 to 2008 the electricity generated by nuclear power increased 3.6-fold while uranium used increased by a factor of only 2.5.

We've continued to more sources of uranium in recent years:

>...The world's known uranium resources increased by at least one-quarter in the last decade due to increased mineral exploration

http://www.world-nuclear.org/information-library/nuclear-fue...

The report simply makes a mention of thorium as an unconventional resource, but doesn't include it in the calculation.

>...Today uranium is the only fuel supplied for nuclear reactors. However, thorium can also be utilised as a fuel for CANDU reactors or in reactors specially designed for this purpose. Neutron efficient reactors, such as CANDU, are capable of operating on a thorium fuel cycle, once they are started using a fissile material such as U-235 or Pu-239.

>...Thorium is reported to be about three times as abundant in the Earth's crust as uranium.

http://www.world-nuclear.org/information-library/nuclear-fue...

With breeder reactors, it becomes economical to get uranium from sea water:

>...Such arguments ignore the fact that usual estimates of the world’s uranium resources refer to quantities available at the current market price of about $40 per pound. At that price, uranium supply contributes about 0.2 cents/kW h to the cost of electricity from light-water reactors. However, if used in breeder reactors, the cost/kW h is reduced by more than a factor of 100, so one can afford to use much more expensive uranium. For example, uranium costing $1000/lb would contribute only 0.03 cents/kW-h to the cost of electricity and would thus represent less than 1 % of the total cost. At that price, the fuel cost would be equivalent to that of gasoline priced at a half cent per gallon. How much uranium is available at a price of $1000 per pound? There are large supplies available at far below that cost in the Conway granite of New England and the Chattanooga Shales of Tennessee, but for the longer-range viewpoint we concentrate here on uranium from the oceans. It now seems quite certain that uranium can be extracted from the ocean at well below $1000 per pound (best estimates are that current technology can produce it at $200–400 per pound) and there is even some optimism that it can 1 become competitive at current market prices ($40/lb). It is clear, then, that uranium from seawater must be considered as a completely acceptable fuel for breeder reactors, contributing less than 1% to the cost of electricity. In terms of fuel cost per million BTU, even at $400/lb the uranium cost is only 1.1 cents, whereas coal costs $1.25, OPEC oil costs $5.70, and natural gas costs $3–4. ... All of the world’s present electrical usage, 650 GWe, could therefore be supplied by the uranium in seawater for (4.6×10 /650) = 7 million years.

http://large.stanford.edu/publications/coal/references/docs/...

Just in the last couple of years there have been advances in getting uranium from seawater which would lower the cost:

>...New technological breakthroughs from DOE’s Pacific Northwest (PNNL) and Oak Ridge (ORNL) national laboratories have made removing uranium from seawater within economic reach and the only question is - when will the source of uranium for our nuclear power plants change from mined ore to seawater extraction? ... Stephen Kung, in DOE's Office of Nuclear Energy, says that “Finding alternatives to uranium ore mining is a necessary step in planning for the future of nuclear energy.” And these advances by PNNL and ORNL have reduced the cost by a factor of four in just five years. But it’s still over $200/lb of U3O8, twice as much as it needs to be to replace mining uranium ore.

Obviously no one is going to pay double (or more) just to get uranium from seawater, but if the price of uranium start to get expensive due to shortages, we can get uranium from seawater with relatively little impact on the price of electricity.

>...the reaction is a fuckton "but what if"

You need to re-read what I wrote. I did not write a bunch of "What if" hypotheticals. I pointed out you missed a huge number of factors that would influence the result. It would be as if someone claimed we couldn't supply the world's power through solar/wind because of the increased need for rare earths and they didn't include the impact of recycling or opening up mining operations in other parts of the word that are currently uneconomical. I would call them out on that just like I did here.


> you ignored reprocessing

dude, can you read 4 sentences or your limit is around two/three? because in the fourth I did consider reprocessing.

> sea water

which only exist in lab test scale and done massively would demolish ecosystems whole, because it's done by dropping huge capture sheets for months long

all of these are about as far from implementation as fusion, and you won't see holding me breath for that. in the meanwhile, we'd be out of uranium and then what are we going to use to bridge the gap?

that's why the 'just build 70x more nuclear plant' is untenable as a whole

but you just cherry picked what was convenient and didn't even brought anything interesting to the discussion, just lab stage prototypes and nothing to get us from here to there, which is the critical part of this thing whole.

same reasoning as the first guy I responded to:

> build 70x more plants > eat up all convenient uranium > ???? > profit!

well guess what, that ??? is what I was addressing. the technology is not yet there. how far is it? we don't even know that yet, that's the amount of information from your links.

and in the between?


>dude, can you read 4 sentences...

Ad Hominem.

We are done here.


Hey man I appreciated you response to my question. I'm frankly very impressed you had the data to back up your assertions.


Sounds like that might tide us over until fusion. We probably should've invested more into fusion.


we don't have working breeder tho




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