Japan To Create a Nuclear Meltdown 222
Taco Cowboy writes "Japanese researchers are planning an experiment to better understand what transpires during a nuclear meltdown by attempting to create a controlled nuclear meltdown. Using a scaled down version of a nuclear reactor — essentially a meter long stainless steel container — the experiment will involve the insertion of a foot long (30 cm) nuclear fuel rod, starting the fission process, and then draining the coolant. The experiment is scheduled to take place later this year."
Great (Score:5, Insightful)
What could possibly go wrong?
By the way, didn't they have to hand in their license to do nuclear stuff already?
What could possibly go wrong? (Score:1, Insightful)
Re:Great (Score:5, Insightful)
I believe that's what they want to find out.
Good Idea (Score:4, Insightful)
It seems so obvious to me now, having seen the idea in print. This is not the sort of thing that is easy to analyze. A test is really a good way to understand the phenomenon. The paradigm where engineers attempt to make sure it never happens has its limits. Looking at what happens during the failure will allow engineers to develop meaningful "defense in depth" measures.
Regards,
Jason C. Wells
Re:Great (Score:5, Insightful)
And, it should be noted, they want to find out in controlled conditions with sufficient protective equipment in a facility explicitly configured for this kind of situation. This is science.
Redundant? (Score:5, Insightful)
Re:Great (Score:5, Insightful)
This is science.
The problem is that it should have been done decades ago. You're supposed to test failure modes before you declare something safe. That's doubly true of something as potentially dangerous as nuclear meltdowns.
Re:Good Idea (Score:5, Insightful)
The paradigm where engineers attempt to make sure it never happens has its limits. Looking at what happens during the failure will allow engineers to develop meaningful "defense in depth" measures.
That was understood decades ago, and has been SOP for that long in other safety critical applications like aircraft. The fact that it wasn't done before this is extreme negligence.
Japan needs their reactors restarted.. (Score:4, Insightful)
The situation with the imports of coal and oil / gas is not sustainable.
Renewable sources are part of it, but they do not have the energy density for baseload required to run a modern society. Japan is a nation with limited resources. Their power options are limited. Import of power from neighbors isn't a great long term move for sovereignty.
This puts them between a rock and a hard place, so to speak. Mark my words though, those reactors will be fired up, because they need to be. They should build more.
The scale of the amount of energy consumed by modern civilization is head-spinning. Nuclear is our only real option. Existing technologies should be deployed, and new ones researched. No politician in the west has the balls to do that, so we're going to burn every drop of oil instead, largely because nobody ever looks at the numbers and amount of energy required. (I however, did.)
Thankfully, China may save us.
I just hope the nuclear option picked isn't the one with the warheads. That will fix the problem too. There is some quality black humor and irony there.
Re:Great (Score:3, Insightful)
The problem is that it should have been done decades ago.
Well at least we're getting round to it now. Nuclear energy was deployed well before it was ready to produce electricity in such scale, and the insecurities we built into the plants because our engineering wasn't up to the task yet produced many violent and unfortunate accidents. But we're going to have to embrace nuclear energy in one form or another if we plan to have a cheap source of clean and reliable energy in the coming centuries. It's best research into preventing nuclear core accidents and preventing any radiation leaks be done as thoroughly and frequently as possible.
Re:Great (Score:5, Insightful)
Fukushima's containment vessel could (and did) contain the molten core... but not the hydrogen explosions that also occurred inside the reactor chamber because of the total coolant loss.
My language should imply that nuclear reactors are safe against the foreseen failure modes. At Fukushima Daiichi, it was not expected that all of the coolant systems would fail at once and that repairs would be hampered by the tsunami damage.
Re:Great (Score:5, Insightful)
Good luck with that. IDB Reference Characteristics of LWR Nuclear Fuel Assemblies from the 1996 Integrated Database Report (copied from Nuclear Tourist [nucleartourist.com]) mentions a fuel rod assembly containing 185 kg uranium. In contrast, Little Boy which destroyed Hiroshima contained 64 kg uranium, and that was certainly not a 100% efficient fission reaction.
It is not realistic to design nuclear power plants to withstand the maximum energy you could get out of the reaction. That would kill off the nuclear industry.
Feel free to start discussing whether it is realistic to get all the energy out of the 185 kg uranium. You can argue that it is less highly enriched than bombs, and that it is entirely unlikely that uranium which is mostly U-238 is going to suddenly decide to fission. I completely agree, but then we are no longer protecting against the maximum energy that could get released.
Re:Great (Score:3, Insightful)
Fukushima's containment vessel could (and did) contain the molten core...
I didn't claim otherwise. I said existing reactors aren't designed to contain a nuclear accident as a whole, so that the environment would be unaffected. Your language implied that existing reactors had that capability, because you reduced what's a whole array of potential safety problems to just the capability of the containment vessel to contain a molten core.