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New nuclear fuel source would power human race until 5000AD

theregister.co.uk

51–60 of 114 posts

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

#51

I really thought this was going to be about Thorium. Surprise - its about extracting Uranium from seawater.

I can not figure out why more effort is not put into thorium nuclear technology research. The only reason I have heard why thorium is not being considered is because it is not weaponizable. Are there any other reasons why thorium based nuclear fission is not being pursued as an energy source?

Uranium is cheap in most places, and we're already set up to use it. In order for thorium to be compelling, you need to either have problems with your uranium supply, or reactors that take advantage of its properties to be better in other ways.

That's why thorium is not a bigger priority. There is some R&D on it; for example, the Chinese pebble bed reactor program is working on using thorium.

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

#52
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…

I don't think there are any Chernobyl-like reactors in operation today. Even if the design of reactors like ones at the Fukushima plant may be considered horribly flawed (they should be able to cool themselves passively, with no external power input whatsoever, after someone hits the scram button) the magnitude of the disaster is much smaller.

An article posted here a couple days back mentions the hot zones around Fukushima are 3x less radioactive than downtown Denver. This is something to think about.

Also, we must consider what other options we have for power generation. Can solar, wind and hydro generate all the power we need? How long until we can build economically viable fusion plants?

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

#53
post #45

Earlier quoted context omitted.

The technology has not been fully developed, there only have been research reactors. Developing reactors for it would require significant investments and apparently no government is willing to invest in it.

>there only have been research reactors Well not exactly. They tried over here, but it eventually lead to nowhere. 2bn for 4 operational years. https://en.wikipedia.org/wiki/THTR-300

That was a solid-fuel reactor. The one people are excited about these days is liquid-fueled. Oak Ridge built a couple small reactors in the 50's and 60's.

Liquid fuel brings several advantages, like being able to extract fission products that poison the reaction, giving you very high fuel efficiency. And if it overheats, a frozen plug melts and drains all the fuel into a tank designed to passively cool it.

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

#54
post #51

Earlier quoted context omitted.

I can not figure out why more effort is not put into thorium nuclear technology research. The only reason I have heard why thorium is not being considered is because it is not weaponizable. Are there any other reasons why thorium based nuclear fission is not being pursued as an energy source?

Uranium is cheap in most places, and we're already set up to use it. In order for thorium to be compelling, you need to either have problems with your uranium supply, or reactors that take advantage of its properties to be better in other ways. That's why thorium is not a bigger priority. There is some R&D on it; for example, the Chinese pebble bed reactor program is working on using thorium.

I guess this is the natural outcome, when we expect the government to be the driver of scientific research. When the ones controlling the purse are also the ones we hold responsible for defense, then defense is bound to be a core focus of what gets researched.

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

#55

I really thought this was going to be about Thorium. Surprise - its about extracting Uranium from seawater.

I assume if you can extract Uranium from sea water, you are very close to extract Thorium. In any case, we are all set up to use Uranium and Thorium still require a lot of R&D, politics and safety regulation before we can start generating commercial power with it.

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

#56

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…

Essentially yes. The ocean is a fantastic dump for radioactive material. Also, it only takes 10 ft of water to block all radiation, alpha, beta and gamma.

However. Radioactive 'waste' is actually really useful. We can recycle it and use it. It's just a matter of regulations and cost. I'd much rather make our radioactive by products readily accessible for when we can use it as either fuel (only need a higher neutron flux) or extract elements for various uses.

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

#57
post #39

as rauljara mentions, the claim that fukishima was victimless is a bit bloated. nothing i've seen or heard leads me to believe that nuclear waste management is a sustainable thing. this sounds like the oceanic equivelant of fracking.

nothing i've seen or heard leads me to believe that nuclear waste management is a sustainable thing

Keep reading.

http://www.world-nuclear.org/info/inf04.html

Disclosure: Former US Navy radiological controls MOS.

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

#58
post #49
post #25

5000AD estimate is complete bullshit. Our energy consumption doubles every ~20 years (15 to 35 by various sources). In only 10 doublings (200 years) our energy consumption will increase 1,000 times. After 20 doublings (400 years), it will increase 1,000,000 times. I expect by then we will be using mostly fusion and/or the energy of the Sun (and/or some new energy source).

Don't you think we might not stay on that curve forever? At some point growth in access to western amenities (climate control, transportation, better food) will level off, and population growth will level off. Also in 1000 years we'll have athletes who finish races before they begin.

> Don't you think we might not stay on that curve forever?

Not forever, but the exponential growth is inevitable while the resources are available and are used more and more efficiently.

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

#59
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 haven't read that book, but I get the point about the critique. I think it's important to acknowledge the many errors that have resulted from both ignorance and negligence, but also to consider how scientific rigor and engineering methodologies like redundancy and planning for failure mean that we don't have to fly blind; also, the more we postpone implementation of alternative designs (such as those for thorium reactors), the greater the risks from maintaining outdated reactors become. There are many reactors that I'd like to see shut down for either design or geographic reasons, and the best argument for decommissioning them is that we can produce the same amount of power at lower cost and risk.

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

#60
The problem with nuclear power generation today is it's always way more expensive than promised, in often unpredictable and sometimes not-easily-quantifiable ways. Add the uninsurable nature, the constant risk of human error/decision making increasing the risk factor (eg. not decommissioning old plants), and waste problem, and it gets even less attractive. Meanwhile, renewable energy and power grid improvements continue to be underfunded, and everyone claims the only alternative is coal.
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