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New nuclear fuel source would power human race until 5000AD

theregister.co.uk

61–70 of 114 posts

Re: New nuclear fuel source would power human race until 5000AD

#61
post #18

Earlier quoted context omitted.

Yes, but growth sucks. Assuming 3000 years in the article means what you think it means, consider exponential and linear growth: If energy usage doubles every 30 years (pulled that out of my ass, it's not likely the trend but divides nice into 3000) then it will last us less than 200 years If energy usage grows linearly increasing by the current amount every 30 years (so in 2042 we are using double, and 2072 we are u…

And in any case, 3000 years is still finite. There will come a time, if we don't go extinct or experience the rapture, when nuclear fuel will run out, and we'll have to use renewables anyway. Fortunately, the sun puts out a rather large amount of power, and even 200 years is a pretty good amount of time for figuring out how to capture it better.

The question really is if going to something 'harder' now is worth while. We do something more expensive (and have large oppertunity cost) to avoid problem we will only really have in 200 years.

If you look at the change of technology in the last 100 years you can only assume how small this problem will be then.

Re: New nuclear fuel source would power human race until 5000AD

#62

Let's reverse the logic. Instead of talking about how much radioactive material we're pulling from the ocean, how much could we put in? Am I mistaken in saying that we could put back in every bit of radioactive material we'd use until 5000AD and only double the natural background radiation amount? I know the math isn't exact -- it's not a symmetry -- but on a rough-order-of-magnitude basis, is that a reasonable concl…

No; the waste is far more radioactive than the fuel. Nuclear fuel rods are perfectly safe to touch when they're first made; they rapidly become more dangerous as they fission in the reactor. By the time they come out they are lethal. Then their lethality slowly dies off as the short-lived fission products decay. It would be a very bad idea to mix raw nuclear waste into the sea.

Re: New nuclear fuel source would power human race until 5000AD

#63

Let's reverse the logic. Instead of talking about how much radioactive material we're pulling from the ocean, how much could we put in? Am I mistaken in saying that we could put back in every bit of radioactive material we'd use until 5000AD and only double the natural background radiation amount? I know the math isn't exact -- it's not a symmetry -- but on a rough-order-of-magnitude basis, is that a reasonable concl…

> but on a rough-order-of-magnitude basis, is that a reasonable conclusion?

No. Uranium is barely radioactive. In contrast the waste from a power plant is very radioactive.

Radioactivity is directly related to half life: The longer the half life, the less radioactive, and the reverse as well.

Uranium 235 has a half life of close to a billion years, and 238 (the much more common kind) of nearly 5 billion years. So it's barely radioactive.

Once you "cook" it in a reactor you generate all sorts of isotopes with much shorter half lives (so none exist naturally in any quantity). Those isotopes are also much more radioactive. The good thing is that the very powerful ones don't last long.

The "worst" isotopes are the medium lived ones. Short enough to be radioactive, long enough to last for centuries. Of those Strontium-90 and Caesium-137 are the main ones.

Now you also know why nuclear fuel reprocessing is a great idea. The uranium left behind after a pass through a reactor has not been changed (it's not any more radioactive than it was before it started) - you can isolate it chemically and use it again (only a small amount actually burns each time). You still need to deal with the dangerous stuff, but the quantity is massively reduced. (Technically you can burn that as well in a reactor to other shorter lived isotopes, and essentially destroy any hazard, but I don't believe anyone does that.)

Just to respond to your actual idea, there are proposals to bury waste in subduction zones. You can find more about it via google https://www.google.com/search?q=nuclear+subduction+zone

Re: New nuclear fuel source would power human race until 5000AD

#64
post #47
post #9

"Since the Fukushima meltdown - as a result of which, not a single person is set to be measurably harmed by radiation - we know that nuclear power is safe." It seems to me like the primary danger from radiation like that leaked from Fukushima would be an increase in cancer. I think it's a little early to be claiming that Fukushima will cause no increase harm to humans. There is already evidence that it caused harm to…

Someone posted an article a while back that estimated that the levels people were exposed to would lead to about 194 extra cancers. http://online.wsj.com/article/SB1000087239639044477240457758...

Oddly enough that can sound good or bad but the wave directly caused ~15,000 deaths, so on that scale it's not really an issue.

Re: New nuclear fuel source would power human race until 5000AD

#65
post #35

Earlier quoted context omitted.

People are more frightened of things they don't understand, so effective advocacy of nuclear power requires making the effort to bridge the information gap. Also, people find concentrated acute harm more scary than dispersed chronic harm, which is why the idea of a plane crash is more disturbing than the larger number of people killed in road accidents.

If you've read Normal Accidents by Perrow, how would you respond to someone who said that a good reason is because of the extreme complexity of nuclear power coupled with our relatively new understanding of it? I think that's a pretty good criticism of nuclear power.

I would ask them if they feared computers, which are more complex, more recent, and used to control almost everything.

Re: New nuclear fuel source would power human race until 5000AD

#66
post #44

Earlier quoted context omitted.

People are more frightened of things they don't understand, so effective advocacy of nuclear power requires making the effort to bridge the information gap. Also, people find concentrated acute harm more scary than dispersed chronic harm, which is why the idea of a plane crash is more disturbing than the larger number of people killed in road accidents.

i think that the biggest problem is the potential for making places on our planet unsuitable to live in forever (for all practical purposes). people look at chernobyl and see a place that will be dangerous to all life long after they're dead. they don't want that to happen again. fukushima is potentially the next such place, albeit on a lower scale. the fact that radiation doesn't hurt doesn't help either. if our civ…

Don't forget about Centralia, Pennsylvania (http://en.wikipedia.org/wiki/Centralia,_Pennsylvania) where an underground coal fire in a coal mine has been burning since 1962, making the town uninhabitable.

Re: New nuclear fuel source would power human race until 5000AD

#67
We seem to be discussing pros and cons of nuclear. But is this assertion of reasonably extractable uranium from sea water even true? Considering the source to be theregister, what I would like to know is whether the energy available as per the paper is really as big as claimed? or is it just clever math? Keeping aside the issue of waste disposal, are the costs really that low or is the cost cleverly buried elsewhere?

Re: New nuclear fuel source would power human race until 5000AD

#68
post #15
post #13

Earlier quoted context omitted.

What is the permanent solution?

There are several. One is to dump it in the Mariana trench, let nature push it back down into the crust. If we're foresighted, we'll bombard a crater in the moon with it. It won't go anywhere, and if we need to get it back, there it is.

[deleted]

Re: New nuclear fuel source would power human race until 5000AD

#70
I thought that the Hacker News community was a lot more alert to avoiding upvoting linkbait articles like this.

First of all, the entire main story point of the article is based on PRESS RELEASES, not on peer-reviewed articles published in good-quality scientific journals.

Second, even if a statement like the premise of the article were published in a peer-reviewed article in a good-quality scientific journal, you would still want to check the methodology of the study described in the article for the "Warning Signs in Experimental Design and Interpretation" that Google's director of research, LISP hacker Peter Norvig, is always warning us about.

http://norvig.com/experiment-design.html

Third, the article is about a public policy proposal, so it's not just about physics, it's about economics and the psychology of the general public as well. As Thomas Sowell has written, "The first lesson of economics is scarcity: There is never enough of anything to satisfy all those who want it. The first lesson of politics is to disregard the first lesson of economics." What the public wants is as much energy as can be humanly desired, with total safety, and at nil cost. The efforts of politicians to reconcile these contradictory desires may very well result in a regulatory pattern that doesn't let this new technology thrive. As a matter of economics, this technology should only thrive if it genuinely provides a better cost-benefit trade-off than other proposed energy technologies, which the article hand-waves away as an issue.

Discussions on Hacker News are better if they are launched by submission of better sources. This source, on this subject, is below general community standards. We can learn more about new possibilities in energy technology from (for example) Technology Review (several HN participants regularly submit articles from that source) or The Economist (I am one of several HN participants who submit articles from that source) or the better professionally edited mainstream newspapers or general news weeklies. We don't need to rush ahead to speculate about every new press release here.

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