Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

A Thorium-Salt Reactor Has Fired Up for the First Time in Four Decades

thoriumenergyworld.com

Post reply on HN
Print view View original

71–80 of 170 posts

Re: A Thorium-Salt Reactor Has Fired Up for the First Time in Four Decades

#71

Post by SoMisanthrope »

jopsen wrote: post #62
SubiculumCode wrote: post #55

Anyone with insight on this I read years ago: http://www.popularmechanics.com/science/energy/a11907/is-the... I worry that that if Thorium reactors become very very common because they are thought to be very safe (e.g. behind your house common, as some have bragged), but they turn out to be dangerous...we will have a real problem.

I think it's unlikely that we'll want to have people playing with radio active waste in their backyard.. We have decent electricity grids, if reactors become financially viable, first goal will be to power the grid. I don't see any profit margin in decentralizing the grid.

Gen IV reactors are more cost effective than solar or wind. https://en.m.wikipedia.org/wiki/Generation_IV_reactor

Passive cooling has already been applied successfully to the US nuclear sub fleet. While most reactors cannot operate at-power, they can be cooled without aid, while sub-critical.

Maybe someday that tech will trickle down to the civilian world?

Re: A Thorium-Salt Reactor Has Fired Up for the First Time in Four Decades

#72

Post by SubiculumCode »

hexane360 wrote: post #61
SubiculumCode wrote: post #55

Anyone with insight on this I read years ago: http://www.popularmechanics.com/science/energy/a11907/is-the... I worry that that if Thorium reactors become very very common because they are thought to be very safe (e.g. behind your house common, as some have bragged), but they turn out to be dangerous...we will have a real problem.

I'm not sure if this is a real possibility given our current understanding of nuclear physics and reactor design. We have enough knowledge to fully understand how a reactor like this would function. Past incidents have been caused by design flaws that were known at the time. It's not a matter of lack of knowledge so much as a lack of good management and regulations.

To be clear the worry was not about a meltdown, but that Thorium can be used to create Plutonium 233, per the article I cited.

Re: A Thorium-Salt Reactor Has Fired Up for the First Time in Four Decades

#73

Post by ornel »

PaulHoule wrote: post #46
mschuster91 wrote: post #37

Earlier quoted context omitted.

> (One thing nuclear does not cause) However, two problems remain: 1) where to get the raw material? African mines are not exactly known for adhering to human or environmental rights, also African mines, by nature of being in Africa, don't create American jobs. Same is valid for the other major sources of nuclear fuel, all of which aren't the USA. 2) where to dump all the nuclear waste? I mean, people have debated to…

The use of thorium in the MSR is perhaps 30x more fuel efficient than the current light water reactor. Large amounts of thorium have been buried in the desert by the U.S. government. Also, sufficient deposits exist in the U.S. to support centuries of use. As for nuclear waste, the real reason why the problem appears intractable is that nuclear waste is not waste. The LWR gets only 2% or so of the energy in uranium, t…

Doesn't reprocessing produce a lot of high level waste as a byproduct, thereby worsening the waste problem?

And I understand the Japanese had an experimental breeder reactor for a long time and never achieved actually producing any commercially viable electricity. They did get lots of plutonium, though, which may be turned into bombs any moment.

Re: A Thorium-Salt Reactor Has Fired Up for the First Time in Four Decades

#74

Post by btilly »

itcrowd wrote: post #66
hexane360 wrote: post #63

Earlier quoted context omitted.

To the downvoters: This is technically correct. #1: (charged particles traveling faster than the speed of light) in water #2: charged particles traveling faster than (the speed of light in water)

Technically, it is technically incorrect. There is no "speed of light", there is only "speed of light in [medium]".* Therefore, interpretation #1 doesn't make sense. Maybe colloquially people refer to the speed of light in vacuum as "the speed of light", but again, that is technically incorrect. *And more technically there's group and phase velocity which may or may not be equal.

This is BS.

Go to 10 physicists and say, "Is c the speed of light?" Odds are that most will say, "Yes." And while some may suggest more exact terminology, not one will fail to understand what you meant.

Furthermore at the subatomic level, light always goes at c. Even if you're in water. It has no other actual speed. Thanks to interactions between light and a medium it looks like photons go slower through the medium. But that's no different than the fact that current traveling through metal acts approximately like it is being carried by electrons of some other mass and velocity. (Or even, in some cases, like the absence of an election. This fact is critical to the operation of a transistor.) But "acts approximately like" and "is" are two different things.

Re: A Thorium-Salt Reactor Has Fired Up for the First Time in Four Decades

#76

Post by Sukotto »

I think we're making a serious PR mistake calling these "Thorium Reactors" even though the term is accurate.

"Reactor" evokes "Nuclear Reactor". For many people, "nuclear reactor" is a deeply loaded term. Likewise "Thorium" (and other words that end in "-ium") sounds dangerously like "plutonium" and "uranium".

It doesn't matter how much better/safer this technology is. Don't expect the public to respond positively when we use those words. There's too much knee jerk, "no nukes!" baggage.

We should start calling these "salt power stations" or something else accurate, yet non-threatening. Otherwise, IMHO, it will be a steep uphill battle getting public and legislative support for building these things, regardless of their many benefits.

Re: A Thorium-Salt Reactor Has Fired Up for the First Time in Four Decades

#77

Post by acidburnNSA »

SubiculumCode wrote: post #72
hexane360 wrote: post #61

Earlier quoted context omitted.

I'm not sure if this is a real possibility given our current understanding of nuclear physics and reactor design. We have enough knowledge to fully understand how a reactor like this would function. Past incidents have been caused by design flaws that were known at the time. It's not a matter of lack of knowledge so much as a lack of good management and regulations.

To be clear the worry was not about a meltdown, but that Thorium can be used to create Plutonium 233, per the article I cited.

Right. A Thorium-232 atom that absorbs a neutron becomes Protactinium-233 which decays to Uranium-233, a fissile nuclide like U-235 and Plutonium-239. This is how the controlled chain reactor works but like any fissile material it also has potential weapons uses. Thus, Thorium reactors require safeguards and monitoring just like any other peaceful nuclear reactor.

Re: A Thorium-Salt Reactor Has Fired Up for the First Time in Four Decades

#78

Post by nnfy »

Sukotto wrote: post #76

I think we're making a serious PR mistake calling these "Thorium Reactors" even though the term is accurate. "Reactor" evokes "Nuclear Reactor". For many people, "nuclear reactor" is a deeply loaded term. Likewise "Thorium" (and other words that end in "-ium") sounds dangerously like "plutonium" and "uranium". It doesn't matter how much better/safer this technology is. Don't expect the public to respond positively wh…

At least this way you convince the educated public that you are credible.

We should avoid names inspired by what amounts to political correctness, because people who see through the names may distrust us further.

However, I do appreciate your point, and I agree that it is a problem. I think the attitude, at least from young white collar professionals, is warming up to nuclear.

Re: A Thorium-Salt Reactor Has Fired Up for the First Time in Four Decades

#79

Post by acidburnNSA »

philipkglass wrote: post #29
igravious wrote: post #15

Earlier quoted context omitted.

I thought it was the other way around in fact. That they don't produce nuke-weapon-ready material meant that this avenue was not profitable from a security perspective. I may be recalling this incorrectly and I haven't re-checked but I think that's correct?

No, that is incorrect, though it has often been repeated by less technically informed advocates of the thorium fuel cycle. The vast majority of the world's commercial nuclear reactors are light-water-moderated pressurized water reactors or boiling water reactors (PWR and BWR respectively). The actual military origins of these light water reactors is that they were originally researched for submarine and ship propulsi…

Oh my god thank you for understanding this and explaining it so well. I spend a lot of time trying to suppress the sinister-LWR myth.

Real reasons MSRs declined include [1]:

* The existing major industrial and utility commitments to the LWR, HTGR, and LMFBR.

* The lack of incentive for industrial investment in supplying fuel cycle services, such as those required for solid fuel reactors.

* The overwhelming manufacturing and operating experience with solid fuel reactors in contrast with the very limited involvement with fluid fueled reactors.

* The less advanced state of MSBR technology and the lack of demonstrated solutions to the major technical problems associated with the MSBR concept.

[1] http://www.energyfromthorium.com/pdf/WASH-1222.pdf

Re: A Thorium-Salt Reactor Has Fired Up for the First Time in Four Decades

#80

Post by NinoScript »

velodrome wrote: post #7

This technology, if viable, could help solve our current nuclear waste problem. Valuable materials could be recycled (by separation) for additional use. https://en.wikipedia.org/wiki/Nuclear_reprocessing#Pyroproce... https://youtu.be/oAVCaUonrbE?t=12m7s

I wasn't expecting to see George Lucas on that video, I kinda got distracted because of him.
Post reply on HN