Out Of Crisis Comes Improvement
It is extremely important that we make a move toward nuclear power and I'm dismayed at those who are using the crisis in Japan to argue that we can't. Ron Bailey has a wiser approach at reason:
One hopeful possibility is that the Japanese crisis will spark the development and deployment of new and even safer nuclear power plants. Already, the Westinghouse division of Toshiba has developed and sold its passively safe AP1000 pressurized water reactor. The reactor is designed with safety systems that would cool down the reactor after an accident without the need for human intervention and operate using natural forces like gravity instead of relying on diesel generators and electric pumps. Until the recent events in Japan, the Nuclear Regulatory Commission was expected to give final approval to the design by this fall despite opposition by some anti-nuclear groups.One innovative approach to using nuclear energy to produce electricity safely is to develop thorium reactors. Thorium is a naturally occurring radioactive element, which, unlike certain isotopes of uranium, cannot sustain a nuclear chain reaction. However, thorium can be doped with enough uranium or plutonium to sustain such a reaction. Liquid fluoride thorium reactors (LFTR) have a lot to recommend them with regard to safety. Fueled by a molten mixture of thorium and uranium dissolved in fluoride salts of lithium and beryllium at atmospheric pressure, LFTRs cannot melt down (strictly speaking the fuel is already melted).
Because LFTRs operate at atmospheric pressure, they are less likely than conventional pressurized reactors to spew radioactive elements if an accident occurs. In addition, an increase in operating temperature slows down the nuclear chain reaction, inherently stabilizing the reactor. And LFTRs are designed with a salt plug at the bottom that melts if reactor temperatures somehow do rise too high, draining reactor fluid into a containment vessel where it essentially freezes.
It is estimated that 83 percent of LFTR waste products are safe within 10 years, while the remainder needs to be stored for 300 years. Another advantage is that LFTRs can use plutonium and nuclear waste as fuel, transmuting them into much less radioactive and harmful elements, thus eliminating the need for waste storage lasting up to 10,000 years. No commercial thorium reactors currently exist, although China announced a project earlier this year that aims to develop such reactors.
Pournelle has a good explanation of numbers and such, but I was struck by this:
"The important lesson from Japan is that we took obsolete reactors with old designs and safety features, and subjected them to a 9.0 quake and a very large tsunami, and the damage to the planet is an unfortunate but hardly decisive event. It is now time to stop worrying about this mess until things settle and we can see precisely what we have learned, and factor that into the next generation designs. Note that almost everywhere in the world we are building reactors with much better design and far better safety features than those being destroyed now. Concentration on how awful is the nuclear mess takes our attention off the economic and human disasters from the earthquake and tsunami." Jerry Pournelle
Jerry in his piece explains that even his numbers are too high, and they are still low... Because this issue will continue until everything is cool, people are going to continue to look at this small nuclear issue, and miss the part where hundreds of thousands are displaced, a million dont have water, and thousands are missing...
I am figuring that this will set nuke energy back another 50 years... look at what the minimal happening at Three Mile did, not much ahs been built since. this is actually bad, and will make the nimby's much stronger in their worrying.
Put another way though... It took a tsunami caused by a 9.0 earthquake to do this. This was NOT caused by the earthquake itself. Imagine how many magnitudes safer a modern design would be?
http://www.jerrypournelle.com/view/2011/Q1/view666.html#worstcase
SwissArmyD at March 16, 2011 10:09 AM
That reactor was 40 years old. The newer ones with updated designs ARE safer. And not because of the situation in Japan.
The tsunami knocked out the diesel back-up generators that were to supply power to pump coolant to the core in the event the reactor was knocked out by an earthquake.
Everything worked as planned...until they ran out of plans. The back-up plan didn't have a back-up plan.
"Plans are nothing. Planning is everything." - Dwight David Eisenhower
Conan the Grammarian at March 16, 2011 10:35 AM
And think of the advantages.
If we are ever invaded in the USA (a near constant fear of right-wing nut-spending on our military, so I assume this is a legitimate fear), we can just tear down the coolant systems on our coastal nukes.
They will blow skyhigh, taking out the invaders with them!
Of course, who would want to invade the USA, and for what reason? But nice to know we have our nuke boobytrap option.
BOTU at March 16, 2011 11:03 AM
Sigh.
"Another advantage is that LFTRs can use plutonium and nuclear waste as fuel, transmuting them into much less radioactive and harmful elements, thus eliminating the need for waste storage lasting up to 10,000 years."
No.
When you cause fission, you produce fission fragments. H and F Tank Farms at Savannah River Site contain 30+ million gallons of previously-processed waste. Hanford has another several million gallons. It is being treated to extract remaining transuranic (heavy metal) isotopes and encase them in specialized glass/stainless steel containers.
Haven't you heard of Yucca Mountain?
The volume can be reduced by removing non-radioactive material, like water, from the mixture of waste and other materials, but a fission fragment is a fission fragment is a fission fragment, and they are produced by the pound in all fission reactor operation.
The waste produced depends on the fuel. Even for gasoline, you're not getting just flowers and bunnies when you start out with crude in the ground.
Radwaste at March 16, 2011 2:57 PM
I'll mention here that the Fujinuma Dam burst on Saturday, washing away houses and leaving behind a pile of dead & missing:
http://en.wikipedia.org/wiki/Fujinuma_Dam
If current events demonstrate that nuclear reactors must be banned forever, then I would be delighted if anti-nuclear activists could point out which structures or sources of energy meet their standards of inherent safety.
Martin at March 16, 2011 7:50 PM
Anyone who remembers TMI and actually looked into it knows that someone developed better fools; not that the system failed.
If you do your research -- you find that some of the best coal comes from the Appalachian mountains. Also uranium nuggets can be found around the Appalachian mountains. Want to take a guess which power plants have a higher background radiation level?
The duck & cover attitude persists to this day. Take a guess who started it?
Jim P. at March 16, 2011 8:43 PM
Raddy, the thorium reactors breed thorium-232 into uranium-233, don't they? Do you know what the typical fission products are for U-233 fission? I'm not finding anything with Google.
Cousin Dave at March 16, 2011 9:16 PM
Here you go Cousin Dave, fission product yields for U-233:
http://ie.lbl.gov/fission/233ut.txt
Martin at March 16, 2011 10:40 PM
For comparison, U-235:
http://ie.lbl.gov/fission/235ut.txt
Martin at March 16, 2011 10:42 PM
And plutonium-239:
http://ie.lbl.gov/fission/239put.txt
Note that yields of some troublesome species like Sr-90 & Cs-137 are somewhat higher for U-233.
Martin at March 16, 2011 10:56 PM
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