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The Rise of Small Nuclear Plants
ColdWetDog writes "The Oil Drum (one of the best sites to discuss the technical details of the Macondo Blowout) is typically focused on ramifications of petroleum use, and in particular the Peak Oil theory. They run short guest articles from time to time on various aspects of energy use and policies. Today they have an interesting article on small nuclear reactors with a refreshing amount of technical detail concerning their construction, use, and fueling. The author's major thesis: 'Pick up almost any book about nuclear energy and you will find that the prevailing wisdom is that nuclear plants must be very large in order to be competitive. This assumption is widely accepted, but, if its roots are understood, it can be effectively challenged. Recently, however, a growing body of plant designers, utility companies, government agencies, and financial players are recognizing that smaller plants can take advantage of greater opportunities to apply lessons learned, take advantage of the engineering and tooling savings possible with higher numbers of units, and better meet customer needs in terms of capacity additions and financing. The resulting systems are a welcome addition to the nuclear power plant menu, which has previously been limited to one size — extra large.'"
To minimize sound possibly?
Not even a little. Nuke plants are noisy. This actually poses a problem aboard nuclear subs. Of course a carrier isn't stealthy to begin with, especially not if deployed in a battle group, so the reactor noise isn't relevant.
The GP asked why the navy would use a nuke if a gas turbine would do the job. Fuel is the biggest answer, as a nuclear reactor needs refueling infrequently, and removing the need for large fuel tanks leaves more room for other stuff - in the case of a carrier, the "other stuff" would include aviation fuel and munitions, two things needed in quantity. In the case of a sub, the reactor is desirable in that it lets you stay submerged more or less indefinitely, since you can electrolyze water for oxygen.
Other than those two situations (carriers and subs), naval nuclear reactors are uncommon for exactly the reason given at the beginning of the thread: cost.
Erotic is when you use a feather. Exotic is when you use the whole chicken.
WRONG. The technology to reprocess nuclear fuel has existed for more than half a century and is currently employed the world over. Just not in the U.S. In fact breeder reactors incorporate reprocessing into the design to use a fraction of the fuel and produce a fraction of the waste of those reactor types permitted in the U.S.
The problem with nuclear waste is one of politics, not of technology. Following on the heels of Gerald Ford's ban of commercial plutonium reprocessing, Jimmy Carter signed an order to ban the reprocessing of spent commercial nuclear fuel. Regan overturned the ban in 1981 but there was no funding provided to start up reprocessing facilities nor has the DOE provided license for anyone to do it. While they've waffled a bit during the Bush-Obama presidencies the DOE presently doesn't want domestic reprocessing. This has accordingly put a rather big crimp in the success of the GNEP which had closed loop nuclear power as a primary goal.
Two of my imaginary friends reproduced once
Sure, if you had some way of searching the ocean for faint traces of hydrogen bubbles, and if said bubbles co-operated by not reacting with anything in the meantime. So far as I know we've never developed anything like that. Now, to put on my paranoid hat for a second, "so far as I know" could just mean that attempts to do this were classified, though I think the easier explanation is that nobody has bothered.
I don't want to say it isn't possible, because that's the sort of sentiment that invites the universe to prove me wrong, but lets just say it's a needle in a haystack sort of problem. You'd be looking for faint chemical trace over a vast area, with the trace in question being chemically reactive enough to virtually guarantee it won't linger. At a minimum, your solution would need to be used over a narrow search region.
Now, look at the problem from the opposite direction. Stealth under water is relative. A submarine, however well designed, however well commanded, can be found using existing methods, provided you know roughly where to look for it. Think of how many shipwrecks have been found by searching the general area they sunk, often decades or more after the fact. Now, factor in that those wrecks are on the ocean floor, meaning it's harder to spot them on active sonar than a sub, that the wrecks are utterly silent instead of just mostly silent, and that many of those wrecks were found using non-military hardware (meaning a few boats with active sonar pinging the ocean floor, instead of a fleet of warships and air-dropped sonar buoys).
The key concept here is knowing where to look. If all you know is that a sub is somewhere in the Atlantic, then you aren't going to have much luck finding it. If you know where to look, you don't need anything like a hypothetical hydrogen searching method when more straightforward options exist.
Erotic is when you use a feather. Exotic is when you use the whole chicken.
Really? and how would keep anyone from taking the whole thing breaking it apart somewhere else and selling the valuable fuel grade uranium on the black market?
Or worse yet, using the uranium and all the radioactive parts of the reactor for a dirty bomb?
Or even worse yet, trying to do one of the above, but fucking up and letting all kinds of radioactive liquids drain in the drinking water underground?
In most of these small reactor designs the fissionable material has nearly no value as a weapon. For example, a Pebble Bed Reactor uses balls of graphite and fissionable material which can be difficult to re-process into something other than fuel. A dirty bomb is of little concern because, again, it's much easier to just mine new material rather than use the fuel for these reactors.
Lastly, the modern designs for reactors are extremely safe. They have less chance of contaminating groundwater supply than building solar panels (a process that requires tons of heavy metals, organic wastes, and wastewater) or operating a coal-fired power plant. Not to mention that once you are done using the fuel and reprocessing it into new fuel you are left with a small amount of concentrated waste with either extremely short (degrades quickly to harmless elements) or extremely long (emits nearly no radiation) lifetimes.
The modern nuclear reactor designs are vastly better than the units built 40+ years ago, it's a shame that we haven't been building them. Instead we are maintaining older units because the red tape is too much to bother building new units to replace the aging ones. THAT'S your recipe for disaster!
Sapere aude!
In 1974, I was a member of the commissioning crew of the USS Virgina (CGN-38). It was nuclear powered. They made several more of that class. When they needed to be refueled they were all decommissioned. So why did the Navy want to pay for the fuel for a conventional powered ship rather than paying the expense of refueling a nuclear powered ship? It is strange since when I retired from the Navy, every ship that I had been a member had already been mothballed even those ships that were built after I had first joined. The only nuclear powered ships today are aircraft carriers and submarines. Submarines are nuclear powered since they do not need oxygen to run. Conventional powered submarines need to surface to run their diesels to recharge their batteries and thus were exposed during that time. Aircraft carriers are large enough to save money over conventional power so unless the Navy goes back to nuclear powered ships, they belief in only big nuclear reactors. It would be nice if the Navy could build a ship with nothing but laser weapons powered by a nuclear reactor.
Nuclear power is cheap and clean. It is cheap enough that France exports large amounts of electricity to Italy, Germany, and the UK. The importing countries closed or scaled down their nuclear power investments to placate local enviro-weenies but are OK importing it, even if the reactors are right next to the border. France has some of the cheapest electricity costs in Europe. So I do not get where you are coming from.
Check the DOE energy reports. In the US nuclear power generates more electricity than wind, solar, hydro and other renewables combined. If CO2 is considered a pollutant there is no clean coal.
I'd recommend looking at this post.
First, the nuclear power industry pretty much has the best safety record going. Per dollar of product produced, it kills the least amount of people. Let's see, in the past decade it's killed, what, 3 people (the 3 Japanese workers in a reprocessing plant that got stupid by using a steel bucket instead of the multi-million machine intended for the purpose). Just this year, in the USA, for oil and natural gas we have the Deepwater horizon, which killed 11. China regularly loses hundreds each year, we lost 25 in the explosion at Massey this year. 34 miners lost their lives the year before in various incidents.
Second - Let's look at Yankee Rowe - third commerical nuclear reactor. Shut down early due to concerns that the reactor vessel might be becoming brittle.
Cost: $36M in 1960, $209M in 2k dollars
Decommission: $450M($567M), worst case. $320M($403M) is the 'basis average'.
During it's life, Yankee Rowe produced 34 Billion kwh, achieving a sub-performing 74% capacity factor - most of the newer reactors still in service are well over 90%.
So, going by an average 3 cents a kwh, that's $1.02B in electricity produced. That leaves $244M for operations and profit during it's time. So not very expensive, though not as good as would be hoped. If you go by the worst case decommission costs. Basis average would be a lot better, as would it have been if the reactor had lasted it's expected lifetime.
Third - You have got to be kidding me. 19.4% in 2007
Fourth - So nuclear power needs loan guarantees to proceed. Wind and Solar power need cash subsidies, often in excess of half their cost! Heck, your 'clean coal' got more subsidies than nuclear - $29.81/MWh for 'clean coal', Solar $24.34 and wind around $23.37, nuclear got only $1.59/MWh
In total dollars:
Refined Coal: $2,156M
Solar: $14M
Wind: $724M
Nuclear: $1,267M
The biggest problem with coal is air pollution. There is technology available to reduce pollution to negligible levels, but nobody wants to use it because it's "too expensive". Instead of flushing a few Billion down the toilet with nuclear power, we could put that money into clean coal technology.
Still have the problems with fly ash and such, so it's still not 'clean', and at that point your 'clean coal' is more expensive to install than nuclear, as well as more expensive to operate.
I don't read AC A human right
And that is why you toss it back into a feeder reactor as fuel to and let the neutron radiation break it down for you.
Yes, sodium gets activated by the neutrons. Yes, it's highly radioactive then. But, it's quite short lived (15 hours for Na-24, 2.6 years for Na-22) so it's not as big a problem as you imply. Na-22 is a beta decay, so that's not problematic. Na-24 is the one that has dangerous radiation as it emits gammas. But with a 15 hour half life, it decays very quickly.
The daughter products aren't a problem either (Ne-22 and Mg-24), they're both stable.
In the US in situ leaching is used.
Basicly you pump a mix of water and baking soda into the ground and the uranium disolves in it.
Then you pump it back up and extract the uranium.
Baking soda isn't high on my list of things I'm afraid of getting in my water.
Pretty clean and safe.
waste storage wouldn't be too hard if it was treated as a technical problem, unfortunatly politicians who consider the words "nuclear" and "satanic" interchangable screwed that one up.