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Nuclear Power Could See a Revival
shmG writes "As the US moves to reduce dependence on oil, the nuclear industry is looking to expand, with new designs making their way through the regulatory process. No less than three new configurations for nuclear power are being considered for licensing by the US Nuclear Regulatory Commission. The first of them could be generating power in Georgia by 2016."
I thought I saw this supposedly quite safe "Pebble Bed" small-scale reactor design reported on then linked to by Slashdot some time ago, but I don't see it mentioned in the article. I am not having luck finding it in the Slashdot search either. Did I dream that? One of the important features of it was that it was "walk-away safe" - as in, were the cooling system to catastrophically fail, it could not achieve "meltdown." In fact, it could be safely repaired and re-started with very little material damage whatsoever.
Actually, thorium should not be anymore complex (probably simpler) than a uranium/plutonium based reactor. But all the years of the cold war and the lure of nuclear weapons has prompted all the engineering to be spent on uranium/plutonium reactors. It's not a physics problem. It's just that since all the current reactors are uranium/plutonium, the engineering is far more developed. From a physics standpoint, thorium is well understood. But from an engineering perspective it is mostly still experimental. If energy production is your only motive, eventually thorium has to win over current conventional reactor designs. It's just a matter of time. Heck, even with the current reactors, the main reason we have nuclear waste is because we do not reprocess fuel. You can thank Jimmy Carter for that decision too. But fast breeders that would have used the waste make it easier to get the resources to build weapons too. War sucks. We need LFTR's!!!!!!
Oh, yeah! Wise guy, huh? Woob woob woob woob! Nyuk! Nyuk!
CANDU can already use spent fuel (along with dismantled warheads)
(according to wiki)
*CANDU fuel can be manufactured from the used (depleted) uranium found in light water reactor (LWR) spent fuel.*
http://en.wikipedia.org/wiki/Candu#Fuel_cycles
I've got better things to do tonight than die.
Now, if we could only reprocess the damn fuel we'd have a clean method of power generation with very little overall waste for a couple hundred years at least.
Integral Fast Reactors
On-site reprocessing of fissile materials to feed the reactor, with only minor extra fuel input required (almost 1.0 ratio reacted fuel, after reprocessing) and can be used to "burn" waste products of other reactors.
Finally had enough. Come see us over at https://soylentnews.org/
It's one thing I'm pissed off at a lot of environuts for, they have a short sighted view that is just black and white. We don't have any commercial reactors here in Australia, mainly because of the environut movements. If they wanted to do good they'd stop the crap and find out what's real and what's not.
On the other hand you have a lot of coal (85% of the electricity production plus exports). And coal by a conservative estimate kills 3 or 4 times the number of people who died due to Chernobyl each year!
Here is an estimate of the number of people whose health is affected by coal based energy production in the USA:
http://www.msnbc.msn.com/id/5174391/
So in my view the environmentalists are in fact responsible for millions of deaths due to their insistence on yet non-viable clean energy sources and their refusal of nuclear energy.
Ok... that remark was based not on the lack of insight with the engineers. It's based on the fact that it's impossible to predict the costs of decommissioning a nuclear power plant 50 years into the future. The shut down is in fact often more than 50 years after it was started up. Costs are often higher than expected (due to increased safety regulations). And I think it's not uncommon that governments have to financially assist companies when reactors are decommissioned.
Why does everyone think of nuclear power (or coal, or natural gas, or renewables) and oil as some sort of zero-sum game? Oil is used for three things mainly: transportation fuel, heating fuel in some parts of the country, and as a raw material for industrial processes. Nuclear power is good for one thing: generating electricity. While I will admit that there is plenty of small ways that we can trade off oil usage for nuclear-generated electricity, there aren't many wholesale ways of reducing oil consumption via nuclear. Are you going to heat your New England home with nuclear electricity? Will you create plastics feedstock from nuclear electricity? Even though in both cases one can do these things, we aren't about to because it's cheaper to do them using oil.
The big one is electricity, and I for one am pessimistic that we'll see a wholesale shift away from gasoline/diesel (i.e., more than 1/3 of all vehicles on the road propelled by electrical power)in anything less than 25 years.
And even then, it's not like we'll magically be trading nuclear electricity off for only imported oil. Oil is a global commodity. The determining factor of where the U.S. gets its oil from is where how much it costs. If it's cheaper or more profitable to bring it by tanker from the Middle East than it is to pull it from the Gulf of Mexico, you can bet that is where we'll get most of it. In truth, where does the U.S. import most of its oil from? Canada. Mexico provides us with as much oil as Saudi Arabia. We get more from non-OPEC nations than we do from OPEC [lots of stats here]. I am glad that the summary used the term "dependence on oil" rather than the more politically useful "foreign oil". I just wish that everyone else could wrap their head around it.
And how do you propose that happens? I'm guessing you are unaware of the fact that all modern nuclear power plants have a negative Moderator Temperature Coefficient. A positive MTC as in Chernobyl means that an increased in temperature causes an increase in power (which loops back on itself).
Highlights in the past 4 years:
Source
And of course, the article that was for this story has more information. But who reads that?
Captainpanic wrote :
Name me one nuclear power station that actually went into operation and stayed within budget while it was constructed, operated and shut down agian.
Sizewell B, a PWR that I was involved in building in the UK, was built within its time and cost budget. Hasn't shut down yet so I can't answer the last part.
"It only reduces the amount of waste if it doesn't produce other kinds of waste in equal amounts."
It doesn't produce more waste than usual.
"I highly doubt that even the newest generation of nuclear reactors takes in fissable heavy metals and outputs something at most as dangerous as CO2. I would be happy if you prove me wrong."
There will be waste, but most of it short-lived (decay to safe levels in 100-200 years). Not as harmless as CO2, but quite close not to worry about it much. As for chemical toxicity, the amount of waste is so small (even with our current reactors) that it doesn't matter. If our waste were as poisonous as arsenic but not radioactive we could have just dumped it in the sea without any problems.
A major part of the expense and construction delays are due to every reactor design being one-off and requiring individual approval by the government. The industry is now (finally) trying to get 'type acceptance' for a few well-engineered designs that can be built exactly to spec much quickly and for a lot less money.
My local utility had chosen (see legend) the GE ESBWR but has switched to the Mitsubishi US-APWR.
Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
"Fissionable material" is somewhat rare.
No it's not. Enriched uranium (U-235), used by current reactor technology, is somewhat rare, accounting for some 0.7% of all naturally occurring uranium. Breeder reactors can run on U-238, which accounts for nearly all of the remaining 99%, as well as Thorium-232, which is considerably more abundant than uranium. Breeder reactors would easily have enough fuel to last us tens of thousands of years at our current electrical consumption rates.
Asking for an example that completed its entire lifespan is basically asking for the first-of-a-kind reactors and very early generation when people were still learning the hard way.
Or the 'lemons' and plants that were shut down more due to political pressure than economic or ecological reality.
Picking the first plant off the decommisioned list at the NRC, 'Connecticut Yankee', Haddam Neck, CT. 582MW (half the size of 'modern' reactors).
Commissioned: 1968
Ceased production: 1996 (28 years)
Decommissioned: 2004
Dome demolished: 2006
Fact sheet, because the wiki page is pretty bare
110 Billion kwh - $4B or so worth of electricity, at low utility rates. 619MW? - may be measuring closer to the reactor, not removing power used to maintain the plant itself.
Decommisioning costs - not listed, but no federal funds are mentioned other than $34.1M awarded to them by the federal courts due to the feds violating the 'Nuclear Waste Policy Act(NWPA)' - The NWPA had nuclear plants pay the government a fee for each kwh generated, in exchange for them taking nuclear waste, starting in 1998. Yucca Mountain, in other words. Since they never took to accepting waste, CY had to store it themselves.
Another: 'Yankee Rowe' - 167MW. 1960-1992, 34B kwh produced($1.3B). Built for something like $45M back in 1960. No idea what the real decommisioning costs were, but was certified 'greenfield' in 1996, except for some land storing the waste until the feds pick it up(per law).
Honestly enough, in my research the feds haven't had to pick up much at all; mostly just paying for waste fuel storage expenses because the feds haven't done their job.
Now, decommission expenses are a very good reason for plants to want to keep operating; if we're really that concerned, just increase the reserve requirements for decommissioning that are built up over the life of the plant.
I don't read AC A human right
I'm kinda curious about their reactors- what systems do they have in place to prevent loss of containment if their ship gets blown to bits?
US ships with reactors are either normally underwater or the size of old WWII battleships. Even the subs are fairly large for WWII combat vessels.
Why do I mention WWII ships? Because we did a lot of testing on them.
Anyways - on to the point:
Ships are TOUGH. Even in wartime they generally dont 'get blown to bits'. Instead they get holed, take on too much water and sink. A number of times combatants ended up scuttling(sinking) their own ships after battle damage rendered them combat ineffective and unable to reach a friendly port or fleet before likely capture. After Pearl Harbor, we actually raised and repaired a number of ships.
After WWII, during testing we actually NUKED a lot of ships. Superstructure would be blown off, sometimes the smaller ships would capsize. Still, the ships were mostly intact when they sank.
So, ships are generally 'mostly intact' even when sunk by battle damage. Reactors are located close to the bottome of the ship and have additional shielding.
Basically, in the case of a uncontrolled sinking, crew or automatic systems SCRAM the reactors. The vessel sinks to the bottom, where the residual heat from the reactor is taken care of by the vast amounts of cold ocean water. If it's in shallow water, we then recover it. Deep water? Generally we leave it.
What if the reactor vessel is breached? Well, Uranium isn't actually all that water soluble, and water doesn't pick radioactivity up that easily. There's already Uranium, Thorium, and other radioactive materials dissolved in seawater. Underwater vents release all sorts of nasty stuff, but also sustain some really wierd life like lobsters that gradually cook themselves while feeding. Speaking of vents - 400C water, but 2" away it's dropped to 2C. That's how much heat dispursion capacity deep water has.
Any damage is likely to be extremely localized. Even if the fuel gets free, it's extremely dense and will likely bury itself into the seabed when it hits.
I don't read AC A human right