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Is Safe, Green Thorium Power Finally Ready For Prime Time?
MrSeb writes "If you've not been tracking the thorium hype, you might be interested to learn that the benefits liquid fluoride thorium reactors (LFTRs) have over light water uranium reactors (LWRs) are compelling. Alvin Weinberg, who invented both, favored the LFTR for civilian power since its failures (when they happened) were considerably less dramatic — a catastrophic depressurization of radioactive steam, like occurred at Chernobyl in 1986, simply wouldn't be possible. Since the technical hurdles to building LFTRs and handling their byproducts are in theory no more challenging, one might ask — where are they? It turns out that a bunch of U.S. startups are investigating the modern-day viability of thorium power, and countries like India and China have serious, governmental efforts to use LFTRs. Is thorium power finally ready for prime time?"
Chernobyl was a graphite moderated water-cooled reactor. Any commercial nuclear plant in the U.S. is a water-moderated and water-cooled reactor.
Despite the normal perception of the word, a "moderator" actually increases the nuclear activity in a fission plant since it slows-down ("moderates") neutrons and therefore increases the probability that the neutrons cause a fission event. In Chernobyl, the coolant (water) was blown away in the pressure explosion, but the moderator (graphite) remained in place which led to the runaway meltdown.
By contrast at Three Mile Island & Fukushima, the loss of coolant led to a meltdown (literally heat causing melting to occur), but since the water moderator was also missing, the accidents did not lead to a runaway that was anywhere near as severe as Chernobyl. If Fukushima had included a pressure vessel of the same caliber as the one used at TMI, then hardly any radioactivity would have been released during the Fukushima accident.
AntiFA: An abbreviation for Anti First Amendment.
Molten salt has a lot of advantages as a working fluid over water, unfortunately the major big disadvantage outweighs all the positives.
Viz. the conditions inside these reactors would be absurdly corrosive. F salts are chemically aggressive, and that aggressive increases with temperature. That is compounded by the fact that the reactor materials will also be bombarded with significant neutron fluxes, and by the presence of all dissolved decay products in the working fluid.
We simply don't have materials that can stand up for any length of time to that kind of abuse.
I have the misfortune of living at ground zero for an ongoing wind farm build. 24/7 truck traffic, massive clouds of dust, hour plus highway shutdowns while they move their superloads, obnoxious subcontractors that ignore traffic laws, etc, etc. Then there's the ecological impact -- acres upon acres of wooded hilltops have been deforested. I truly had no idea how obnoxious it was until Google Earth got updated images. Take a look at some before and after photos of a large wind farm and see for yourself how bad it is.
All of this might be worth it if wind energy scaled the same as nuclear, or could provide the same power density, but both of those are utterly impossible. You'll never match nuclear reactions for power density, and the footprint of a nuclear power plant is no larger than that of any other modern industrial concern.
Everything in life is a tradeoff, but having lived near Three Mile Island, and now living in the midst of a wind farm, I'd take the former any day of the week. You simply didn't know TMI was there, unless you happened to have cause to drive by it. Contrast that to dozens of wind turbines, visible for miles around, along with the obnoxiousness of their build process.
Nuclear and low impact hydro are the way to go for base load. Natural gas, along with wind, and solar for the peak load.
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
Unfortunately, by the time the evidence is clear enough for even the most ardent skeptic to take seriously, it will be too late to reverse the effects.
The title of your post asks a question, that question is What's-his-name law.
Since the law in question is "If the title asks a question, then the answer is no."
Therefor it is No's Law.
Don't know something? Look it up. Still don't know? Then ask.
The article indicates that Adm. Rickover didn't like molten salt / sodium cooled reactors because the "Navy knew how to handle water". In reality, Rickover's nuclear program tried both approaches. The Nautilus (SSN-571) used a boiling water reactor, and the Seawolf (SSN-575) used a sodium cooled reactor. Both were built, both went to sea, and both performed reasonably well. But the sodium-cooled reactor turned out to be harder to maintain than the boiling water reactor, and couldn't be run at full capacity because of some design problems. so after a year, Seawolf was returned to the yards and converted to a boiling water reactor.
That was very typical of the military approach of the period - fully develop several alternatives, operate them, then dump the losers. The history of 1950s jet fighters is a striking example.
U-232 is also produced in LFTR reactors, and is HELLACIOUSLY radioactive. You can't work around U-232 with just a glove-box - you're gonna get a tan that way. It also poisons the reaction of a U-233 bomb, so you've got to separate it out, so you're back to centrifuges and the like, and you're gonna have to throw out the contaminated and radioactive centrifuges when you're done as well.
Meldroc, Waster of Electrons
In this case, Dr. No is Ian Betteridge, who coined Betteridge's Law (though obviously the idea has been around long before him).
Please define 'a lot of R&D'!
We know that breeding fissle from T90 will work.
We know the heat expansion characteristics of LF coolant/moderator.
We understand most of the implications around shutdown.
We understand far to little about the chemistry of making the reactor survive for a resonable length of time.
We understand only part of the chemistry required to seperate out various byproducts (required for a LFTR to operate)
We know there is plenty of T90 around to convert.
So yes there is a LOTS of chemical engineering to be done but there are no known show stoppers at this time.
From this we can be sure that radiation leaks are very unlikely.
Whereas is would be VERY difficult for a group of raiders to swoop in and steal the fissle material.
It would be easy for, say a government, to stockpile the fissle after it cools down. Say 6 weeks or so.
You have a very caustic liquid at hundreds of degrees which is infused with very large amounts of high level radioactive waste. Fission daughter products which in a regular reactor are solid and encased in zirconium steel and treated with utmost care are now free floating in something very hot, flowing and caustic. What if if there's an accident and it rains. Or a flood. The fission products are very water soluble.
Every power plant also has to be a very nasty chemical separation and reprocessing plant. Consider the contamination just in "normal" operation. And consider the people running them.
What happens if it cools off and solidifies? You've frozen radioactive waste in the pipes a multi-billion dollar plant, and you can't go in there for decades.
There aren't some failure modes of existing reactors, but there are other failure modes and problems.
It might be a good idea to have one or two, very highly regulated and operated with the utmost skill (i.e. not for profit) used to burn up actinides wastes from other reactors.
Coal power has rendered a good sized area including a whole town uninhabitable for the foreseeable future. A fire started in a coal seam and just won't go out. The CO levels in the town range from harmful to deadly depending on the wind at the time. Eventually, it will all fall into a sinkhole and burn.