It would be useful if TFA would acknowledge that their opposing opinion is from a "nuclear analyst" employed by an organization which is founded on the opposition of nuclear energy in general. Just sayin.
Last year or maybe two years ago a bunch of Redditors, physicists and engineers, were talking about getting together and actually making a LFTR or doing something along those lines.
I believe you can build a powerplant that produces less than 5 megawatts without special permission in California, and I don't think thorium is a controlled substance.
It's hard to respect an article that doesn't even mention that Thorium isn't fissile.
Myself, I expect serious development of thorium reactors to come after spikes in the price of oil and uranium, not before. Uranium and fossil fuels are just too cheap right now to justify the additional effort associated with the Thorium fuel cycle.
> If a town of 1,000 bought a 1-megawatt thorium reactor for $250,000, using 20 kilograms of thorium a year with almost no oversight, every family could pay as little as $0.40 a year for all their electricity...
Are they really arguing that thorium power would be too cheap to meter?
Uranium is a pretty small part of the cost of generating nuclear power. (<10%) What makes nuclear power expensive is the tremendous upfront cost of building a safe reactor.
Thorium reactors aren't magic; they're still nuclear reactors. They produce plenty of radioactive waste. A thorium reactor might not be as susceptible to certain types of failure as a uranium reactor, but they're still dangerous enough that it will be necessary to build them to a similarly high standard.
In some ways, thorium could be more expensive. Thorium reactors need a kick-start from a uranium reactor, so they're inherently more complicated. Thorium waste decays faster, but more intensely. Some tasks that can be done by hand in uranium reactors would require robotics in a thorium plant.
Thorium may or may not be a good idea. But to assume that it will be cheaper than uranium is a bit foolish after witnessing what a graveyard uranium reactors made of such dreams over the past sixty years.
Thank you for the skepticism. I think articles such as this need it.
If it ends up working all the better but to be ignorant of the tribulations will only lead to dismay.
We don't use thorium today because you can't make bombs from it. Uranium was chosen back in the 40s because you can bombs from the waste produced by a nuclear reactor.
The primary cost of nuclear power generation is decommissioning the reactor after the power generation is over. The Federal Government has 1 trillion dollars in nuclear reactor coming down the road. The nuclear power "industry" is long gone at that point. The decommissioned reactors get spun off into their own little corporation , and the parent corp has it declare bankruptcy, sticking us with the cost of clean up.
They don't need a kickstart from uranium. You stick thorium into the fluoride salt, the thourium absorbs particles (neutrons I think), it turns into uranium, and then goes through fission. The uranium left over is minimal.
You need a neutron source to start the transmutation of thorium into uranium. AFAIK, in every thorium reactor built to date that source is uranium mixed into the fuel.
The Manhattan Project started as something purely theoretical and produced a working, practical technology in less than a decade. Apollo 11 put men on the moon 8 years after JFK committed the country to that goal.
Both projects succeeded because they were made high national priorities, were well funded, and a "critical mass" of the best and brightest were recruited to get the job done. I don't think there's any reason to doubt that we could have practical nuclear fusion power technology in a similar time frame if the political willpower is there to give it the same high priority status that the Manhattan Project and Apollo had.
Salient points, but for the international collaboration and billions ( well! ) spent on fusion research and decades of promises thats its 10-20 years away. It's a tougher nut to crack than fission. Come on - you can get a pile to start a chain reaction pretty much accidentally. Fusion is fundamentally harder. Kinda hard to replicate a star.
I'd bet that if you were to ask a group of the scientists who are currently working on fusion technology what activity consumes most of their time and effort, the #1 answer would be "pursuing grant money". Ask an academic in any field that question and that is the answer you'll usually get. Eliminate that problem by getting all of those brains together in a well-funded lab and I think you'd be surprised at how much more productive they could be.
It's not replicating a star. As a quote from wikipedia:
The power production by fusion in the core varies with distance from the solar center. At the center of the Sun, theoretical models estimate it to be approximately 276.5 watts/m3,[41] a power production density that more nearly approximates reptile metabolism than a thermonuclear bomb.[note 2] Peak power production in the Sun has been compared to the volumetric heats generated in an active compost heap. The tremendous power output of the Sun is not due to its high power per volume, but instead due to its large size.
Fusion generators seek to harness this power where temperatures exceed millions of K. And then we use magnetic "bottles" to hold fusion in. The main problem is how to insert more material without breaking containment. As far as I can tell, it's always going to be 50 years away. I'd say that micro-singularity reactors are 'closer' than fusion.
I apologize for over-generalizing. I realize it isn't replicating a star.
The nifty thing about being a star is that you have this massive gravitational force available as your containment.
No matter how we do fusion, we'll likely need containment, and it's a vastly harder problem than "put enough fissile atoms close enough together to sustain a chain reaction." Let's face it - the big reason that fission reactors are dangerous is that stopping a reaction is as difficult or often more difficult than starting it.
There's an premise here that nuclear power is currently unsafe, which I think needs to be placed in the context of the less scary but much more widespread environmental impact of fossil-fuel based power generation.
I would suggest human beings are unsafe. It's human beings that put all Fukushima's 20 backup diesel generators in the basement, but put no backup diesel generators a few stories above or on stilts raised above a flood. Two backup diesel generator installed a few stories up, and none of this happens.
The Dutch have put their water pump generators up a few stories for a long time. New Orleans had power for their water pumps raised a few stories pre-Katrina.
Thorium, Uranium, whatever. Just make sure that whatever new reactors you make have negative void coefficients, so they shut themselves off if they get too hot. There's no reason civilian power reactors to make the same design trade offs that let us cram a nuclear reactor into a submarine.
Or are designed to get hot. Very High Temperature Reactors (VHTR) such as the pebble bed reactor design are much simpler than current designs and cool by natural circulation, the don't rely on control rods, coolant pumps, or other active systems that can fail. China are prototyping them, and research is going on elsewhere as well.
Yes, pebble beds are an example of a reactor with a negative void coefficient, since as they get hotter the substance in the outer shell of the pebble expands increasing the distance between the radioactive elements.
There's a bunch of reasons why Thorium cycle reactors, specifically molten salt reactors, haven't gained traction, but this is my favorite (via wikipedia):
>It poses a business challenge, because reactor manufacturers customarily get their long-term profits from fuel fabrication.
Glad to see razor blades, cell phones and printer cartridges aren't alone in the world.
Uranium is the dominant technology for the same reason that we use Linux. There might be better OS designs, but unices are well-established, well-understood and are tied deeply into the economic system as a whole.
The technology to turn uranium into energy is a spinoff of the nuclear weapons firmament. Swords into expensive ploughshares and all that.
There have been...what, three nuclear plant failures EVER? Ignoring Chernobyl (which was caused by political pressure on the operators of one of the earliest plants ever built) there have been a few hundred deaths attributable to nuclear energy. Compare that on a GW / fatality basis to coal mines, hydro plants, etc, and nuclear power is clearly the safest option around.
As to Fukushima...the fifth most powerful earthquake ever recorded went off a few dozen miles away with a total energy release of something like 600 million Hiroshima bombs. This caused tidal waves up to 30 feet high that rolled almost halfway around the world. Despite all that, the total effect was a thermal explosion and some radioactive steam was vented. Yes, it's bad, but it's hardly a good reason to give up the best and safest form of energy known.
You left out plutonium in the ground soil indicating a possible partial meltdown. Since,as you point out, there are only 3 failure datapoints, waiting to see how this one plays out could shed significant light on nuclear safety.
I think similarly to planes and automobiles, people over-value emotional, anecdotal evidence over scientific, verifiable evidence by a large margin when it comes to unfamiliar events. As much as you are more likely to die on the way to the airport, it's easier to visualize dying horrifically in a plane crash than in the car, as one is much rarer and harder to understand than one which you ride in every day without issue.
I think the solution to this could be to incentivize tolerance of nuclear power (maybe tax breaks to live within N miles of one), and educate those unaware of the difference, until it becomes familiar to people.
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[ 3.2 ms ] story [ 86.9 ms ] threadFound this http://www.reddit.com/r/technology/comments/a8v7q/reddit_tho...
Myself, I expect serious development of thorium reactors to come after spikes in the price of oil and uranium, not before. Uranium and fossil fuels are just too cheap right now to justify the additional effort associated with the Thorium fuel cycle.
Are they really arguing that thorium power would be too cheap to meter?
Uranium is a pretty small part of the cost of generating nuclear power. (<10%) What makes nuclear power expensive is the tremendous upfront cost of building a safe reactor.
Thorium reactors aren't magic; they're still nuclear reactors. They produce plenty of radioactive waste. A thorium reactor might not be as susceptible to certain types of failure as a uranium reactor, but they're still dangerous enough that it will be necessary to build them to a similarly high standard.
In some ways, thorium could be more expensive. Thorium reactors need a kick-start from a uranium reactor, so they're inherently more complicated. Thorium waste decays faster, but more intensely. Some tasks that can be done by hand in uranium reactors would require robotics in a thorium plant.
Thorium may or may not be a good idea. But to assume that it will be cheaper than uranium is a bit foolish after witnessing what a graveyard uranium reactors made of such dreams over the past sixty years.
Like you said, cost of fuel is a small part of generating energy. Besides, PG&E would mark up for the "privilege" of using their power. ;)
The primary cost of nuclear power generation is decommissioning the reactor after the power generation is over. The Federal Government has 1 trillion dollars in nuclear reactor coming down the road. The nuclear power "industry" is long gone at that point. The decommissioned reactors get spun off into their own little corporation , and the parent corp has it declare bankruptcy, sticking us with the cost of clean up.
That's something the Thorium proponents never told me.
Both projects succeeded because they were made high national priorities, were well funded, and a "critical mass" of the best and brightest were recruited to get the job done. I don't think there's any reason to doubt that we could have practical nuclear fusion power technology in a similar time frame if the political willpower is there to give it the same high priority status that the Manhattan Project and Apollo had.
The nifty thing about being a star is that you have this massive gravitational force available as your containment.
No matter how we do fusion, we'll likely need containment, and it's a vastly harder problem than "put enough fissile atoms close enough together to sustain a chain reaction." Let's face it - the big reason that fission reactors are dangerous is that stopping a reaction is as difficult or often more difficult than starting it.
The Dutch have put their water pump generators up a few stories for a long time. New Orleans had power for their water pumps raised a few stories pre-Katrina.
>It poses a business challenge, because reactor manufacturers customarily get their long-term profits from fuel fabrication.
Glad to see razor blades, cell phones and printer cartridges aren't alone in the world.
The technology to turn uranium into energy is a spinoff of the nuclear weapons firmament. Swords into expensive ploughshares and all that.
There have been...what, three nuclear plant failures EVER? Ignoring Chernobyl (which was caused by political pressure on the operators of one of the earliest plants ever built) there have been a few hundred deaths attributable to nuclear energy. Compare that on a GW / fatality basis to coal mines, hydro plants, etc, and nuclear power is clearly the safest option around.
As to Fukushima...the fifth most powerful earthquake ever recorded went off a few dozen miles away with a total energy release of something like 600 million Hiroshima bombs. This caused tidal waves up to 30 feet high that rolled almost halfway around the world. Despite all that, the total effect was a thermal explosion and some radioactive steam was vented. Yes, it's bad, but it's hardly a good reason to give up the best and safest form of energy known.
I think the solution to this could be to incentivize tolerance of nuclear power (maybe tax breaks to live within N miles of one), and educate those unaware of the difference, until it becomes familiar to people.
After all, if nuclear power was so safe, why do they have to pay people to live near the station? (Etc, etc.)
All human beings make mistakes. Nuclear reactors do not tolerate mistakes.