We operated 5 high power, uncontained graphite moderated production reactors at Hanford for years, along with N-reactor, a combined production/power reactor of the same type. I toured N-reactor while it was operating in 1969. JFK thought it was important enough to attend it's groundbreaking.
N-reactor was shutdown in 1987 and has since been dismantled.
My point being that these plant ran for probably 100 plant/years without a serious incident. Not the safest possible design, but, with competent workers, not a "crime against humanity" either.
Vaughn, Ontario Hydro uses the Candu reactors which are heavy water reactors, would this make a difference in thier ability to quickly handle grid load demands?
You would need to ask someone who knows for sure, but I doubt it. (I am an ex-nuclear reactor operator, not a nuclear scientist)
The principle works like this: For a reactor to work, there must be some substance to slow the neutrons down so that some of them can successfully mate with an atom of uranium. This substance is called a moderator. Water makes a great moderator (heavy water makes an even better moderator). When you heat up water(even heavy water), it gets less dense and then it does not moderate as well. When you cool down water, it gets denser, moderates better, you get more fission reactions, which generates more power, which heats up the reactor, which heats up the water, which reduces its density, which tends to reduce the reactor's power.
So let's review: When you place more load on the reactor, you are drawing heat from it, which tends to cool it down, which tends to make it produce more power. This is the famous "negative power coeficient" that makes pressurized water reactors tend to automatically produce exactly the proper amont of energy.
There are design factors that can give a reactor more or less temperature coeficient, but the main reason that nuclear reactors are ran nearly "flat out" is because of the cheap fuel, not because it is difficult to control their output power. You would not want to live within 100 miles of a nuclear reactor that was difficult to control.
On Wed, 10 Oct 2007 05:33:50 -0700, with neither quill nor qualm, "azotic" quickly quoth:
Hell, we haven't been able to get past bullshit the enviros like Rachel Carson (_Silent Spring_ author) spewed even though she later disovered that her research was bogus and _recanted_ much of it! Thinner eggshells in raptor eggs had been happening or over fifty years before DDT was invented.
The fear mongers for nuclear still play the worst case scenario despite thousands of man years of good manners on the part of nuke reactors.
Let's hope that the enviros find coal too polluting (it really is; ditto charcoal) and opt for nuke power some time in the near future.
-- Ultimately, the only power to which man should aspire is that which he exercises over himself. -- Elie Wiesel
If you know that much, then you also know that the Chernobyl plant was built without a containment barrier, and it damn sure was a "crime against humanity" that would never have been allowed in the western world. And you also know that no commercial graphite moderated power reactor has ever been built in the United States (for good reason). Chernobyl is only useful as an example if you insist on scaremongering, because no truly civilized society would allow such a dangerous thing to be built.
On Wed, 10 Oct 2007 23:08:24 -0400, with neither quill nor qualm, "Ed Huntress" quickly quoth:
Shit, you would ask that. I've read it in several places. First in _State of Fear_ (not one you'd recognize as valid), then in, um, I think in one of Ronald Bailey's books, probably _Earth Report 2000_. I'll see if I can scare up an exact quote.
In the interim, check these out:
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-- Ultimately, the only power to which man should aspire is that which he exercises over himself. -- Elie Wiesel
Note that I didn't *demand* "cites," only that I asked if you wouldn't mind saving me some time, if you knew where your information came from. d8-)
I'm aware of the controversies surrounding _Silent Spring_. I was just curious about what she is supposed to have said that would amount to recanting "much of it."
BTW, and FWIW, the last two of those articles grossly misrepresent the evidence on DDT and eggshell thinning. There really is no scientific controversy about it, and there hasn't been since the early '70s. I don't know about the scientific evidence for or against general claims concerning toxic pesticides, but the DDT/eggshell research is one I do know about.
We *did* build uncontained graphite moderated reactors. Nine of them by my count. Many of the Hanford production reactors ran at thermal power levels greater than most commercial power reactors. N-Reactor, which supplied commercial power for many years ran at 4000MW.
So my question is, were the 9 Hanford reactors a "crime against humanity", safetywise?
And you missed my point twice, apparently purposely. I was specifically talking about commercial power reactors. I make no claim to any special knowledge about the Hanford reactors, but the honest answer to your question might well be "yes" on many levels, not just safetywise. Both sides did some really despicable things to gain advantage in the cold war. For example: I have been to the medical clinic for the Rocky Flats workers that were purposely not educated about the dangers of the materials they were working with. It is not a pretty sight.
That said, the discussion has been about commercial uses of nuclear power, not military weaponry.
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