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Distributed "Nuclear Batteries" the New Infrastructure Answer?
Posted by
ScuttleMonkey
on Mon Jan 05, 2009 03:59 PM
from the not-in-my-backyard dept.
from the not-in-my-backyard dept.
thepacketmaster writes "The Star reports about a new power generation model using smaller distributed power generators located closer to the consumer. This saves money on power generation lines and creates an infrastructure that can be more easily expanded with smaller incremental steps, compared to bigger centralized power generation projects. The generators in line for this are green sources, but Hyperion Power Generation, NuScale, Adams Atomic Engines (and some other companies) are offering small nuclear reactors to plug into this type of infrastructure. The generator from Hyperion is about the size of a garden shed, and uses older technology that is not capable of creating nuclear warheads, and supposedly self-regulating so it won't go critical. They envision burying reactors near the consumers for 5-10 years, digging them back up and recycling them. Since they are so low maintenance and self-contained, they are calling them nuclear batteries."
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Critical (Score:5, Insightful)
Well, it has to go critical (k=1) if there is a constant power output...
Re:Critical (Score:5, Informative)
Parent
Re:Critical (Score:5, Insightful)
That's exactly right, but people prefer letting the papers think for them.
I don't know if that's it so much as the "papers" seem to know what they're talking about. I don't. Critical? K? These are things I know nothing about. There are people on /. who swear on all things holy that nuclear power is completely safe, almost to the point of suggesting Chernobyl and 3 mile island were trivial, not actually radioactive, or hoaxes. There seem to be other people who say there is no such thing as safe nuclear power. Both camps seem to know a lot more about it than I do. You guys work it out and then tell me which it is. In the mean time, I'm pulling for solar power. It works for plants, and I have yet to hear any controversey about will solar panels explode. And don't suggest that people who don't know the ins and outs of nuclear power are dumb or I'll start quizing you on developmental neurobiology.
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Re:Critical (Score:5, Informative)
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Re:Critical (Score:5, Informative)
Also Chernobyl was due to bad design and poor saftey and maintainence procedures.
Nuke is not 100% safe, but you could also get crushed under a solar panel or more-likely have the chemicals and other pollutants used in making the panel poison you.
Nuke can be safe and clean as well as relatively cheep with proper care and maintenance. It isn't a gift from Maya the Earth Goddess but then again it isn't a scheme by some villain from Captain Planet either.
Parent
Re:Critical (Score:5, Informative)
Very true but perhaps understated. Even the poor procedures at Chernobyl were ignored. From what I have seen, the operators in the space of an hour managed to do practically every DON'T in their procedural manual, including overriding the safety systems to withdraw more control rods than was permitted under any circumstance.
That coupled with an inherently unsafe design and wildly fluctuating power output (due also to operator error) perfectly set the reactor up for a thermal runaway.
With appropriate fuel reprocessing, nuclear has the potential for the LEAST environmental impact of any power source including wind (kills birds, spoils view), solar (takes up large land areas), and hydro (kills fish, prevents return to spawning grounds).
Parent
Re:Critical (Score:5, Informative)
I remember reading that it takes more energy to build a Solar power system than that system will deliver in it's expected lifespan. Is this true?
No.
To elaborate: picture a 200W solar panel [solarhome.org], it weighs about 30lbs and has a lifetime of 20 years or more. In those 20 years, if you average 8 hours a day of full output, that's 1.6kWh per day, or over 11 Megawatt hours. A moderately sized factory might consume [wikipedia.org] 11 megawatts, but if it's that big, it had better be turning out more than 1 solar panel per hour.
Parent
Re:Critical (Score:5, Informative)
Disclaimer: That's not to say that we haven't learned anything in the 40 years since TMI was designed. I find it absurd that we stopped making nuke plants. We should be building shiny new safe ones so that we can decommission all the old time bombs.
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Re:Critical (Score:5, Informative)
The "saving the day" was way after the meltdown. The big concern was the hydrogen bubble formed in the reactor vessel by the reaction between steam and the much hotter than normal Zircaloy fuel cladding. The problem was the risk of the hydrogen causing an explosion that would rupture the vessel.
The meltdown was a concern from the regard of waste handling (as you can't simply pull the fuel cells out of the core like for a normal refueling) and due to the risk of destroying the first layer of containment (the reactor vessel). Even if the melting core material had ruptured the vessel however, that's why reactors in Western nations have a containment vessel to hold the contaminated material (and keep radiation levels outside the containment vessel at background levels).
Keep in mind that TMI-2 was scrammed the entire time the core was melting down -- this was not a runaway nuclear reaction, this was a loss of core cooling (a nuclear core will generate "decay heat" for some time after it is shutdown). So a meltdown is not a concern for radiation generation per se but rather for nuclear plant integrity.
Are nuclear meltdowns an issue? Of course they are -- they wreck a tremendously expensive nuclear core and the cleanup is it itself even more expensive than normal. But it is nowhere near the same league as Chernobyl (which violently blew up due to managing to achieve "prompt criticality [wikipedia.org]", which is the criticality you want to avoid).
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Re:Critical (Score:5, Insightful)
3 mile island was trivial. Chernobyl was due to crappy Soviet engineering, management, and maintenance. We've had plenty of time to learn from their mistakes.
Solar panels don't explode, but every solar panel is manufactured with some pretty nasty chemicals. Is the guaranteed environmental impact of manufacturing billions of solar panels less of an issue than the minuscule risk of a melt down?
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Re:Critical (Score:5, Interesting)
You say nuclear power's problems have been mitigated by learning from our mistakes, why would the same not be true for solar?
The use of nasty chemicals in solar manufacturing is not a "mistake", it's an intentional and necessary part of the process. I won't say it's impossible not to, but that would be the discovery of a fantastic new manufacturing technique, not learning from a mistake.
Whereas Chernobyl was a mistake that we have learned from.
Parent
Sexay! (Score:5, Funny)
Three-headed fish coming to a pond near you!
why not just do this with solar. (Score:5, Interesting)
why bring back the risk of meltdown/contamination. This can be achieved using solar and wind. same distributed concept. Just instead of a power cell you have a house covered with solar panels or a wind generator.
Yes this wont' work everywhere but it is viable in many high demand locations ergo Southern California.
Re:why not just do this with solar. (Score:5, Informative)
Solar takes a lot of space and puts out a lot less power. It's also costlier. And the process of manufacturing solar panels is horrible for the environment.
Nuclear power is, believe it or not, the cleanest technology we have available, even if you consider the highly radioactive waste and the (typically minute) risk of meltdown.
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Re:why not just do this with solar. (Score:5, Insightful)
Pebblebeds, here we come!
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Re:why not just do this with solar. (Score:4, Insightful)
Are you dense? Nuclear = 24/7 power. Solar = sometimes power.
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Re:why not just do this with solar. (Score:5, Interesting)
Batteries aren't efficient for a large scale solution. They're short-lived, they're low capacity, and energy is lost in the charging process.
Batteries using crappy technology are all of those things, but there's one battery technology that was invented 108 years ago that still impresses: the Edison Cell; nickel-iron-potash. Yeah, admittedly it's bulky and heavy per kwh, and expensive, and capacity temporarily takes a hit in a cold environment, but it's not short lived. There are cases on record where these have been in service (or worse, put away and neglected) for 50 or more years, and are still in perfect condition with nearly 100% of their original as-built capacity.
They have no memory effect; they tolerate conditions that kill other types, such as being left indefinitely in a fully discharged state, or grossly overcharged, or kept on indefinite float charge; the plates do not degrade; electrolyte vapour or spills do not corrode metals in the nearby environment.
They can be readily acquired in cell sizes up to 1220ah 1.2v, even by individuals. The cells can be put in series and series-parallel to get any desired energy capacity.
http://en.wikipedia.org/wiki/Edison_cell [wikipedia.org]
http://www.beutilityfree.com/content/index.php?option=com_content&view=article&id=44&Itemid=129 [beutilityfree.com]
http://www.beutilityfree.com/content/pdf_files/NiFeFlyer.pdf [beutilityfree.com]
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Advantages of nukes. (Score:5, Insightful)
They are more flexible and more reliable.
1. You can site them anywhere. Solar and wind have to be sited where there is solar and wind.
2. They are available 24/7. Solar and wind are up to mother nature.
3. They have a higher power density. You need less area to power a bunch of homes. This translates into more safety, and ultimately a lower land use footprint, leaving more room for, well, things that live in the environment.
4. Lower environmental risk. We have barely studied the long term effects caused by draining energy out of the wind, or, of robbing the ground from solar energy to convert to electricity. The aggregate effects of billions of windmills and solar panels upon the earth are not understood. With nukes, we know the risks. We might have a meltdown, some radiation, and a leak, but that's about it.
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Re:why not just do this with solar. (Score:4, Insightful)
Windfarms are only profitable with government subsidy; wind mills cost more energy than they make in there serviceable lifetime (Hence the need for subsidy). Bad for bat populations, which are already in decline.
Solar panels are fantastically bad environmentally. They require the production of green house gasses far worse than CO2, lifetimes are limited and exponentially decay. They require toxic batteries to work, and are unreliable due to weather. 14% efficiency. Also, bad for ground-level wildlife.
The only real alternatives are:
Those are listed from worst to best in terms of available output.
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Wow; combat garbage with more garbage, eh? (Score:4, Informative)
The subsidies are far far far less than what is plowed into Coal, oil, OR NUKES. In addition, with our the subsidies, wind produces less than
As to the bats, well, how much life do you think is dying from Mercury, lead, etc. emission in the air by coal and oil. How many died from that recent ash release?
Solar panels are fantastically bad environmentally. They require the production of green house gasses far worse than CO2, lifetimes are limited and exponentially decay. They require toxic batteries to work, and are unreliable due to weather. 14% efficiency. Also, bad for ground-level wildlife.
You are kidding, right? Green House gases far worse than CO2. Like water? Limited Lifetime? You mean 30-50 years? They require energy storage to work 24x7 (i.e. base power), not necessarily toxic batteries. 14% efficieny? The systems vary any where from 7% (thin film) to 35% on newer products (using mags). Bad for ground-level wildlife? You mean something on the roof is bad for the ground? Hmmmm.
Of course, the worse part about your statement is that it assumes SOlar PV. Solar Thermal is actually at the same cost as coal.
The only real alternatives are:
Solar algae (2-4% efficient)
Geo-thermal (limited places)
Wave/tidal (possible local environmental impacts, high maintenance costs)
Nuclear (low risk, high output, radioactive half-lives are down to 200 years)
Again wow. Just wow.
Solar Thermal was missed in all your stuff.
Algae 2-4% efficient?????
Geo-thermal. Have you even read the current study by MIT? Google for it. If you consider only shallow geo-thermal, then USA will only produce about 10GW of power via it. BUT deep geo-thermal can produce more than 1/2 of America's total power need (that assumes everything on electrical) before 2050.
Nukes half-lives down to 200 years? ONLY if you run it through IFR. Of course, that was killed and the program needs to be re-started (if nothing else, just to use our nuclear waste up).
Look, I am a big fan of nukes (more of the IFR), BUT, spreading garbage about AE does not help the cause. This is
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Re:why not just do this with solar. (Score:5, Funny)
I like this concept. *cough* Get something that could meltdown,
Better get that cough looked at, might be from the local coal plant.
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Re:why not just do this with solar. (Score:4, Informative)
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Re:why not just do this with solar. (Score:5, Informative)
to be fair there would be virtually no waste to worry about if reprocessing were allowed.
Our current problem is that spent fuel still contains much fissle material, and reprocessing fuel rods to get the material out is disallowed by the DOE.
If you reprocessed the fuel to make new fuel, and were left with only the low level waste then the radiation hazard would be fairly comparable with coal ash.
-nB
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Re:why not just do this with solar. (Score:5, Interesting)
"Virtually no waste" translates into "Japan believes it has correctly accounted for all the plutonium in its reprocessing network even though accounting errors have resulted in a thousand kilograms going missing."
Reprocessing is clearly a desirable thing to do from all kinds of standpoints, but the issues of safe transport for the cores and actually maintaining a sufficiently accurate inventory on the fissile material create huge practical problems.
Remember, over a decade or two you will be moving millions of kg of material around for reprocessing, so if you inventory control is 99.9% accurate you will still have enough missing plutonium to make a hundred-odd nice little nuclear bombs.
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Re:why not just do this with solar. (Score:5, Insightful)
The best would be to recycle the waste and whatever is left over put into a subduction zone.
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Re:why not just do this with solar. (Score:5, Insightful)
Why fire it into the sun? Reprocess it, and throw it back in the reactor. Do that enough times, and the stuff you pull out at the end would be "cool" waste: easy to store, not all that radioactive.
The waste problem right now is extreme because the amount of fissile material left in the waste is huge. The reason we don't reprocess is essentially political; reprocessed waste can very easily be "bomb grade" fissile material.
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Re:why not just do this with solar. (Score:5, Insightful)
Nuclear is only 'green' when you exclude the waste issue.
And the (radioactive) pollution caused by uranium mining for the indigenous people of northern Niger and other places.
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BIG psychological barrier (Score:5, Insightful)
Remember, there are still people out there that think powerlines cause cancer, and that vaccinations cause autism, despite scientific evidence.
Nuclear uis a huge red button. I don't think this option is politically viable except in rare circumstances.
I can see it working for small islands and other population centers that are far away/cut off from other population centers. If you are talking about a largish island that has no power supply on it, then it might work. Or an Alaskan town far from everywhere else.
But I can't see someone putting one of these things say in the middle of NYC, Los Angelos, or even on Long Island
Re:BIG psychological barrier (Score:5, Interesting)
Parent
Peace through mini nukes! (Score:5, Informative)
The liquid metal reactor takes advantage of the physical properties of a fissile metal hydride, such as uranium hydride, which serves as a combination fuel and moderator. The invention is self-stabilizing and requires no moving mechanical components to control nuclear criticality. In contrast with customary designs, the control of the nuclear activity is achieved through the temperature driven mobility of the hydrogen isotope contained in the hydride. If the core temperature increases above a set point, the hydrogen isotope dissociates from the hydride and escapes out of the core, the moderation drops and the power production decreases. If the temperature drops, the hydrogen isotope is again associated by the fissile metal hydride and the process is reversed. The chemical isotope splits chemically when it gets too hot. Just like water boils and turns into steam, you can design the water system to not exceed the boiling point of water. You would have to keep the water under pressure to force higher temperatures.
The safety systems will be similar but the reactor cores are different between the Triga (fuel rods in a pool type reactor) and the Hyperion Power Generation Uranium Hydride (liquid metal) reactor.
If you were going to blow it up, it would take a lot of explosives -like blowing up a 15-20 ton buried bank vault. A lot of explosives to penetrate the concrete cask and then more to blow through however many feet of dirt it is buried under.
It would not add much to the cost to have sensors and digital video camera security to these things. So extreme tunneling, attempts to move it or blow it up should be easily detectable and action taken.
For the amount of effort and explosives it would take then just take those explosives and add radioactive material (available in mines and in less secure facilities and sources) and then put your dirty bomb anywhere. Thus there is no incremental risk.
The nuclear material is tougher to turn into nuclear bombs than using raw uranium, which a terrorist could get from natural sources (mines etc...). Again no incremental risk (we are adding no new risk as there is an easier existing path).
For getting oil from oil shale this system can supply heat instead of natural gas. Hyperion also offers a 70% reduction in operating costs (based on costs for field-generation of steam in oil-shale recovery operations), from $11 per million BTU for natural gas to $3 per million BTU for Hyperion. Over five years, a single Hyperion reactor can save $2 billion in operating costs in a heavy oil field. A lot of the initial one hundred orders are from oil and gas companies.
A single truck can deliver the HPM heat source to a site. The device is supposed to be able to produce 70 MW of thermal energy for 5 years. That means that the truck will be delivering about 10.5 trillion BTU's to the site. Natural gas costs about $7 per million BTU which would would cost $73 million.
It would be better to compare the HPM to diesel fuel, which currently costs about 2 times as much per unit of useful heat as natural gas and still requires some form of delivery for remote locations. In some places, fuel transportation costs are two or three times as much as the cost of the fuel from the central supply points.
In certain very difficult terrains, or in places where there are people who like to shoot at tankers, delivery costs can be 100 times as much as the basic cost of the fuel.
Initially these units will be in remote areas near oil sand projects and they will not be directly under people's houses. Do people live directly over power transformers or oil refineries ? The first few thousand can be placed on the site of existing nuclear and coal plants which have a few square miles of space. Even if there eventually there was one for every twenty thousand or ten thousand homes, they would be situated in some industrial zoned area. For eastern europe and island developments, the units will be sited several hundred meters from where people
NIMBY (Score:4, Insightful)
Yup. (Score:3, Insightful)
Not exactly. (Score:5, Insightful)
"Hyperion Power Generation Inc. has developed a garden shed-sized nuclear reactor that can produce enough heat to generate 25 megawatts of electricity for up to 10 years.
That's enough energy to power 20,000 homes, but still tiny by current nuclear standards."
These are not going to be burried in peoples back years.
A small town might have one city may have a few scattered around. A factory may have one or a data center.
As too what could go wrong? Well maybe they are as safe as they say. I would be willing to bet that they are pretty dang safe. If so then they could be great. Think of all the small villages in Northern Canada or Alaska that depend on diesel fuel truck or flown in. Or think of small nations like the Bahamas.
Yea this sounds great if it is safe.
Rapid discharge nuclear battery... (Score:3, Funny)
http://www.globalsecurity.org/wmd/systems/images/w87-design.jpg [globalsecurity.org]
Say Aircraft carrier (Score:5, Insightful)
These have been working of submarines and aircraft carriers for decades.
It is high time some of that military tech comes to civilian use.
If you are afraid of nuclear power, you are on the wrong website.
This is supposed to be for technologically informed people.
Yes, start in remote areas. Islands etc where running power lines is a major expensse would be the best places to start. NY and LA prefer to export the pollution to the suburbs.
I always get a kick out of this... (Score:5, Insightful)
But America gets half its power from coal, which dumps literally tons of thorium and uranium and mercury into the air due to fly ash every year.
Re:I always get a kick out of this... (Score:5, Informative)
One reactor design is made to prevent critical events from forming. Toshiba's 4S reactor. The reactor uses a neutron reflector to bounce neutrons back at the reactor core, heating it up as the reflector moves up and down. The faster the reflector moves, the more energy is produced. Something breaks, meeting SCRAM conditions, the reflector simply stops moving, the reactions stop, moving back down to relative background conditions. The design is modular, the core is sealed at the factory and moved to the site in a single piece containment vessel. Being sodium cooled poses risks, but is manageable.
This design will provide 10 MW @ 75% capacity for 20-30 years.
Parent
Technical inaccuracy in summary. (Score:4, Interesting)
"The generator from Hyperion is about the size of a garden shed, and uses older technology that is not capable of creating nuclear warheads, and supposedly self-regulating so it won't go critical."
This statement is incorrect, a reactor has to be critical to produce power.
Criticality refers to the rate at which the chain reaction of fission is occurring. If the reactor is sub-critical, then more neutrons are absorbed then causing new fissions. In this state, the reactor power exponentially decreases to zero. When the reactor is critical, exactly 1 fission is caused on average for each neutron released, which means the reactor is at a constant power. Super-critical means the reactor is increasing in power. A special case of criticality related to nuclear bombs is called prompt-super-critical. For more info, see the wiki [wikipedia.org] article.
I am not sure of the details of these designs, but I bet they use a fuel type similar to university research reactors. This fuel is a uranium-hydride mixture. The moderation for the neutrons is built into the fuel itself, but it has an extremely strong negative temperature coefficient. This means that any increase in power, and thus temperature, reduces the reactivity, which lowers the power back to the equilibrium level. It is physically impossible for the reactor to overpower.
For a neat demonstration of this effect, see this youtube video [youtube.com]. It is the research reactor at Penn State performing a pulse. Basically, a control rod is hydraulically ejected from the core, causing the power to spike to thousands of times the rated power, but only for a microsecond. The power just as quickly goes back down to normal by itself, because of the intrinsic safety of the fuel design.
Re:Didn't the Russians do this? (Score:4, Informative)
I did on-site service work recently for a 'union man' who did some work at a nearby nuclear power plant. He told me that after they were suited up they walked in and decided they were bill gates, mr burns, and homer simpson. They were told to move a radioactive part and 'burns' asked 'gates' if he was going to go get that. He said, "Hell no, I'm not moving that fucking thing. I'm Bill Gates, I'll buy homer a six-pack and that dumb bastard'll do it". Apparently the staff at the plant didn't find it as funny as they did.
He also had screen by screen pictures of the computer-based nuclear safety exams they all used to cheat their way in and could have walked right off the set of the sopranos but that is another story.
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Re:Didn't the Russians do this? (Score:4, Informative)
Probably RTGs [wikipedia.org], which the USSR put in a lot of lighthouses and other remote places that needed power (with poor documentation, so nobody knows where all these things are anymore). They take a radioactive source (preferably a pure-alpha emitter, since they're easy to sheild, but theoretically any radiation will work) then use the Seeback effect to generate electricity.
What it sounds like they're doing in this article is having an actual nuclear reactor with fissionable material, rather than just generating power off of radiation. They seal it up, bury it, and don't expect to have to do any maintenance for 10 years or so. The fuel source is unsuitable for weapons (it could, of course, make a dirty bomb, but those are more about fear mongering than an actual threat), and has the same self-regulating properties as a pebble bed, where fission simply stops if it gets too hot. At $30 million each, I could easily see these getting bought by medium-sized municipalities to cover their energy needs, though it's a bit much for the totally decentralized grid that the article talks about.
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Re:Didn't the Russians do this? (Score:4, Funny)
> the travellers slept by them for the tens of thousands of watts of heat they throw off
When I travel in cold climates I often like to sleep next to tens of thousands of watts of heat. Really takes the edge of a frosty night. Of course I'll sleep by megawatts of heat if I can find it, for a real warm night.
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Re:Need more guarantees than that (Score:5, Interesting)
Most reactors are built in such a way that automatically prevents them from going over critical (critical is where you want to be, as someone already pointed out). The very nature of their design, assuming something doesn't mess up, keeps them safe.
The thing is, even though reactors are built with countless safety features, something could still go wrong. That's why you have professionals constantly (or at least daily) monitoring everything. Now, if you go and produce millions of mini-reactors, put them in the backyards of regular citizens, give them nothing but automated monitoring, and leave them going for awhile, something is eventually going to go wrong. It still might work on a one-community-at-a-time basis, though. As long as appropriate precautions are taken, nuclear power is extremely effective and clean (compared to coal).
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Re:Need more guarantees than that (Score:5, Insightful)
So you know the full environmental impact of covering deserts with solar collectors, do you? You wouldn't half look stupid if your desert became a wetland in a short space of time because you cooled the region too much.
Removing significant amounts of energy from waves and tides could also have interesting environmental side effects.
Basically you're going to get some form of side effect whenever you convert large amounts of energy from one form to another. The questions are: what are the effects, and are we willing to accept them?
Not saying nuclear is better. just pointing out the downside (never mentioned, possibly unknown) of the so-called "renewable" energy sources.
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Re:Need more guarantees than that (Score:4, Insightful)
"So many more sane options than nuclear."
Umm not at all. Western Nuclear power stations have a great safety record. The soviet reactor that people like to throw out would never be built in the west.
Also tides and waves are to different things and tidal power only works in certain locations and could have a large impact on the environment.
We don't have ample power from dams and geothermal. They are limited as well.
Calling nuclear power insane is just mindless FUD.
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Re:Need more guarantees than that (Score:5, Interesting)
Summary is incorrect. The "nuclear battery" (incorrect name) would have a 99.5% chance of "going critical". After all, that's what nuclear power plants do. What they mean is that the plant would have an infinitesimally small chance of achieving super-criticality. Super-criticality would be a very bad thing, but even that can be mitigated with enough cement. End result? The reactor will be as safe or safer than installing a Diesel Generator in the same location. But it will be more powerful, economical, and environmentally friendly.
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Re:Need more guarantees than that (Score:4, Interesting)
Summary is incorrect. The "nuclear battery" (incorrect name) would have a 99.5% chance of "going critical". After all, that's what nuclear power plants do. What they mean is that the plant would have an infinitesimally small chance of achieving super-criticality. Super-criticality would be a very bad thing, but even that can be mitigated with enough cement.
Even plain-ol criticality (or sub- for that matter) can be bad if it's producing too much heat for the system to take out. Say for example because whatever fluid is being used to extract said heat for power generation purposes stops flowing. Then you have a meltdown, i.e. the nuclear core melting. TFA says it's meltdown, not criticality, that is virtually impossible, so score another one for bad /. summaries.
The modern way to prevent this is with naturally self-regulating reactors (as opposed to say relying on control rods to cool the reactor down). Pebble bed reactors do it by having the uranium in the center of the pebbles so that at the right temperatures they are at the right density for a critical reaction. When they get hotter, they expand, and the reaction slows down. Natural, physical self-regulation. No machine to fail, no control logic to have a bug, it's the laws of physics saving your ass. I like that.
Here's the paragraph on how this one works: "When uranium hydride gets too hot, above 550 degrees Celsius, it will shed hydrogen atoms. The hydrogen flows out of the core and is stored in special storage trays within the reactor. As the fuel loses hydrogen atoms it begins to naturally cool. As it cools, it will retrieve the hydrogen atoms from the trays."
So again, self-regulating based on temperature, sounds pretty cool. The only thing I don't like is that it still relies on a fluid flow, so if somehow the storage trays were collapsed in a way that didn't let the hydrogen to escape, I would think that the increased pressure would mean the uranium hydride would hold onto its hydrogen at higher temperatures. But I'm anything but a chemist or nuclear physicist.
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Re:Need more guarantees than that (Score:5, Informative)
The irony is that a Coal Plant is actually MORE radioactive than a Nuclear Plant!!
http://www.sciam.com/article.cfm?id=coal-ash-is-more-radioactive-than-nuclear-waste [sciam.com]
Hint: It in the ashes and it affect 1 mile around it. Don't eat stuff from your garden!
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reading is hard.... (Score:4, Funny)
I think that you'd have to be realy drunk to drive 75mph UNDERGROUND.
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Re:nuclear warheads? (Score:5, Informative)
There are two kinds of nuclear bomb-- Uranium and Plutonium. In order to get a Uranium bomb, you have to have highly enriched Uranium (a high U-235 to U-238 ratio). These reactors don't have anywhere near the U-235 ratio for that. The second option is Plutonium which is not a naturally-occurring substance. It is the by-product of some kinds of fission, and can be made in a specially designed nuclear reactor. These aren't those kinds of reactors, so you're not going to get enough Plutonium to be useful in weapons development.
Thus, one of these things wouldn't be much of a head-start over just mining some Uranium ore.
Parent
Re:Edison wins, in the end (Score:4, Informative)
The concept of "local power" was first advocated by... Thomas Edison. He was advocating small power stations all around a municipality for local distribution via his DC-based systems.
Westinghouse's AC system, however, allowed for transmission of power great distances. Despite using his name, and some patents, most of what we use today owes more to Westinghouse than Edison.
Just for clarity (and to shake my fist at Schoolhouse Rock), if you're going to refer to Edison's DC, then you should refer to Tesla's AC (not Westinghouse's). And the only reason Edison "advocated small power stations all around a municipality" was because that's the only way his baby, DC, would work. DC just doesn't travel well.
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