A $200-Million Floating Nuclear Plant?

Roland Piquepaille writes "In 'A Floating Chernobyl?,' Popular Science reports that two Russian companies plan to build the world's first floating nuclear power plant to deliver cheap electricity to northern territories. The construction should start next year for a deployment in 2010. The huge barge will be home for two 60-megawatt nuclear reactors which will work until 2050... if everything works fine. It looks like a frightening idea, don't you think? But read more for additional details and pictures of this floating nuclear power plant."

Safety

[LiquidCoooled]

Where else could you get an unlimited supply of coolant?

Hell, if this goes pear shaped, you could drop the core miles beneath the sea never to be seen again.

Nuclear isn't necessarily scary

[selil]

Nuclear power isn't necessarily scarier than coal or oil fired furnaces doing the same thing. The critical issues of radioactivity have largely been fixed. Pebble Bed Reactors and other self monitoring technologies also don't produce waste product like other types of reactor.

Pirates?

[TiraX]

Maybe pirating can be a reborn and profitable proffesion again? yarr?

It could be worse

[solevita]

Nuclear disasters on ships waiting to happen are nothing new in that area of the world. Russia still maintains a policy of keeping nuclear waste onboard container ships in the Arctic Sea:

http://news.bbc.co.uk/2/hi/europe/5391586.stm

Hardly the first floating Nuclear Power Plant

[balsy2001]

The US and Russian Navies have been doing this for 50 years! This is the first commercial venture to do it, but the military has done it safely and effectively. The US Navy has over 5500 reactor years of operations without a nulcear accident. Also, this is not the first time that power from these reactors has been put into the power grid. Any US Navy vessel that is in port and connected to shore power (which they almost always do in port) can and have provided electricity to the grid if needed. This was done in charleston after a huricane.

Re:Nuclear isn't necessarily scary

[ObsessiveMathsFreak]

Pebble Bed Reactors and other self monitoring technologies also don't produce waste product like other types of reactor.

Yes, instead they convert unspent nuclear material into PR-atons, a mysterious form of matter than passes through everything except gullible brain material, a substance which they interact with causing delusions of security and wellbeing.

I'm not even going to bother linking to the Wikipedia article on PBRs as it's long since been pitted and scarred by the feuding and petty editing between the various factions in the nuclear power debate. What I will say is that pebble bed reactors do produce nuclear waste. Quite a lot as it turns out. But probably not as much as buring peat logs, or cows breaking wind or whatever else someone decides to bring up.

Quite frankly, I seriously doubt that nuclear power is even all that cheap anymore, once the cost of PR spreading FUD is factored in.

Re:USS Enterprise, Nimitz, etc

[LWATCDR]

Actually you are incorrect.
The Enterprise actually has 8 reactors! The Enterprise was so expensive that the next class of carriers where not The Kitty Hawk class had four ships in it. Two of them are still in service.
What everyone is forgetting is the US did build a floating reactor into an old Liberty ship. In the late sixties it was used in Panama.

Re:Land-based power supply troubles?

[balsy2001]

Fuel rods are typically stationary. What moves are control rods, typically made of materials with high neutron cross sections like Hf. Reactors can also put nuclear poison into the reactor coolant to help reduce the reactivity of the core. You are correct about reactors (at least all of the ones I am familiar with) do have fail safe systems that shut down the reactor during an accident. They plant can produce all of the power it needs (just like navy vessels). Therefore, it needs no other power source.

Re:So

[Anonymous Coward]

"The worlds finest nuclear powered aircraft carrier"

Those who said that were smoking crack. As a former Navy Nuke I am fully aware that the Enterprise (aka the 'Exposureprise') was certainly a groundbreaking (seabreaking?) nuclear craft. And it is a fairly safe nuclear ship. But lets just say that there were a lot of lessons learned from this ship that the US Navy decided to fix with newer designs. Probably the finest nuclear aircraft carrier would by any of the more modern Nimitz class carriers. They were able to be built with decades of experience from Naval prototype reactors, submarine reactors, and of course shiploads of experience from the Enterprise.

Re:Land-based power supply troubles?

[X-rated Ouroboros]

In multi-core facilities, it's not uncommon to have power for the offline plants' coolant pumps supplied by the operating plant. I'm not aware of any nuclear power plant design that is not capable of being self-sustaining insofar as suppling it's own power loads while operating. If this is a single core design (haven't RTFA), you'd need shore power to keep the plant systems running when the reactor is shutdown for maintenance. Also, the fuel doesn't move. Control rods of neutron absorbing material are moved to control core reactivity.

Re:Land-based power supply troubles?

[Chayak]

That's technically incorrect... you don't withdraw the fuel rods. You lower the control rods. With modern reactors it's very hard to have them melt down as many will scram automatically if outside of set parameters. That and there is always ways to inject material into the primary coolant loop that will greatly impede fission esentially killing the reactor until it is flushed out. I can't go into very much detail on any of it but I served on one of those US underwater nuclear power plants for a number of years.

Article is misleading...

[Tavor]

A floating Chernobyl is unlikely.
Although these articles don't specify, it's likely the floating NPP (Nuclear Power Plant) will be based on the VVER design (which is inheriantly a lot more stable) as opposed to the RBMK that Chernobyl used. The RBMK [wikipedia.org] design had a nasty design flaw, which the world became aware of in 1986 [wikipedia.org].

That being said, the RBMK design has been made much safer since the Soviet era, with many remaining reactors being decommissioned soon anyway. So yeah, apparently TFA's author didn't do their homework.

Re:Land-based power supply troubles?

[coobird]

The output of a nuclear reactor is controlled by inserting and withdrawing the control rods [wikipedia.org] into the core, which controls the rate of the fission chain reaction by absorbing neutrons. (Absorbing the right number of neutrons is the key to keeping the reactor critial [wikipedia.org], where the fission events are allowed to run at a constant output, or subcritical where the chain reaction is suppressed.) The control rods are moved in and out of the reactor core using motors or other mechanisms, which usually require power.

A nuclear power plant itself needs power for the monitoring and operations of the systems that run the plant. Pumping the coolant in the cooling loops, moving the control rods in and out of the core, monitoring of the system status, and other tasks needed to run the plant, requires power.

A nuclear power plant is only producing electrical power when its stream turbines are running -- and there are times when the turbines aren't running such as during maintainance or testing, a time when the plant is referred to as being "offline." Even if the turbines aren't making power, the reactor core needs to be constantly cooled, as the radioactivity from the core (from the fissile fuel and fission products) gives off heat. Basically, at all times when the plant is still in operation (even if no power is being generated) the nuclear power plant needs power.

Re:USS Enterprise, Nimitz, etc

[Libertarian001]

The Big-E (my boat) has 8 reactors. That's not because they thought it was a good idea, but because it was a test-bed. Their are several different reactor and steam plants (GE and Westinghouse, different versions of each) on that ship. Those 8 reactors are comparable in output to the 2 used on all the Nimitz class CVNs.

To my knowledge, all US CVNs other than the Enterprise have just 2 reactors. IIRC, subs have just the one (but I wasn't a bubblehead, so don't quote me).

Re:Nuclear Is Quite Scary

[Terrigena]

Anything nuclear will create waste, you are mistake. Pebble Bed reactors are designed to prevent catastrophic reactions, but these are still possible. A containment leak would allow the atmosphere within the reactor to reach temperatures high enough to melt the graphite moderating cuticle. Pebble bed reactors are not realistic in an age of terrorism, they produce more waste and the mechanised fuel handling is more likely to result in disaster (see Hamm-Uentrop, West Germany). Never mind the logistics of TRACKING each and every pebble from its birth to final resting place in yucca mountain (which is near a fault line). The problem of nuclear energy and its waste has not been solved. As long as waste remains on the planet, it is a threat. I have absolutely NO IDEA how anyone could claim that the problem of nuclear waste is no longer a problem. I think the only explanation is the radiation from too much time spent within the leaky storage facilities at hanford or eating potatoes growing near Chernobyl has gotten to you. Look no further than the Hanford Nuclear Reservation in Eastern Washington (US). Our Federal government has done a good job of keeping this disaster under wraps for the most part. This is because the administration would like you to believe nuclear energy is safe, so that they can gain public support for the reintroduction of the technology to our energy production matrix.

Re:Nuclear isn't necessarily scary

[dasunt]

I believe (and correct me if I'm wrong) that the really nasty waste tends to be really nasty for short periods of time -- years or decades. Radioactivity is energy, and materials that are highly radioactive are releasing a lot of energy at a rate it cannot sustain for a long period of time.

The low-level radiation tends to last for a lot longer, since it releases less energy.

A candle that burns twice as bright burns half as long.

This is also why nuclear power plants have cooling pools for nuclear waste -- for the first few years, the waste produces enough heat (energy) and radioactivity to make moving and storing much more difficult.

*cues "the more you know" music*

Btw, many nuclear wastes tend to be heavy metals, and thus are prone to causing heavy metal poisoning. But this seems to be often (purposely?) overlooked, since opponents of nuclear power seem to focus on the much more "scary" radioactivy, and proponents don't want to mention more downsides of nuclear power.

Umm....

[kf6auf]

The USS Enterprise has 8 A2W reactors (210 MW) and Nimitz class aircraft carriers have 2 A4W reactors (194MW). So yeah, 2x60W reactors can power much less than a nuclear aircraft carrier.

Re:Safety

[Anonymous Coward]

We're talking about TWO full scale reactors on a barge.

No, these are only 60-Megawatt reactors. Full scale nuclear reactors are about 1,000-Megawatts.

Re:Safety

[kextyn]

I just want to point out a few facts here. Nimitz class carrier has 2 A4W reactors outputting 94 MW each. These carriers also have a crew of 3,200 ship's company and 2,480 in the air wing. This new facility will be powered by 2 KLT-40S reactors outputting 60 MW each. So yes, this may be a different scale of power generation. But it's a smaller scale then what the US Navy has floating already.

Re:Land-based power supply troubles?

[TooMuchToDo]

You are indeed correct Sir. This is called a SCRAM. In the event of a catastrophic failure, electric motors release rods into the reactor to completely shutdown the fission reaction. In the US, I believe this is mandatory to have a commercial reactor in production.

From Wikipedia: http://en.wikipedia.org/wiki/SCRAM [wikipedia.org]

"In modern nuclear power plants, the control rods are lifted by electric motors against both their own weight and a powerful spring. A SCRAM rapidly (less than four seconds, by test) releases the control rods from those motors and allows their weight and the spring to drive them into the reactor core, thus halting the nuclear reaction as rapidly as possible."

Also, most people are ill-informed as to why Chernobyl occured:

From Wikipedia: http://en.wikipedia.org/wiki/Void_coefficient [wikipedia.org]

"A positive void coefficient means that the thermal power output increases as the void content inside the reactor increases due to increased boiling or loss of liquid moderator or coolant. If the void coefficient is large enough and control systems do not respond quickly enough, this can form a positive feedback loop which can quickly boil all the coolant in the reactor. This happened in the Chernobyl accident."

It's illegal to build positive void coefficient reactors in the US for this reason. Negative coefficient reactors won't have runaway reactions.

Re:Safety

[trentblase]

This thing: 2 60MW reactors Nimitz Class Aircraft carrier: 194MW I'd say it's about the same scale. http://www.naval-technology.com/projects/nimitz/ [naval-technology.com]

Small reactors

[AJWM]

We're talking about TWO full scale reactors on a barge.

No, we're talking two relatively small reactors on a barge. Typical nuclear power reactors for feeding the electrical grid are in the 600 to 1000 megawatt range, not 60 MW, and most facilities have more than one (the Pickering and Darlington facilities near Toronto have 8 650 MW and 4 850 MW reactors respectively).

The reactors aboard an aircraft carrier do more than just run the lights, they can push the whole thing at speeds in excess of 40 knots (how much in excess isn't exactly talked about -- but even that is more than fast enough to water ski behind!). Ditto for nuclear subs -- plus they provide air and water for the crew (hydrolysis and reverse osmosis).

Modern nuclear submarines typically use reactors up to 200 MW, the French Rubis-class subs use a 48 MW reactor, Russia's Oskar-II class uses 2 190 MW reactors. Surface ships like aircraft carriers or the Kirov-class battle cruiser use two reactors each up to 300 MW each.

Re:Nuclear isn't necessarily scary

[Waffle Iron]

Yep - and the so-called 'Clean Coal' approach concentrates naturally occurring radioactivity to the extent that the waste produced by even the most modern coal fired power plants has comparable amounts of radioactivity to nuclear plants.

That's just plain wrong. You're confusing the oft-quoted factoid that a coal plant *releases* more radioactivity into the environment than a nuclear plant along with its long-term storage facilities. (As long as Murphy's law is held at bay for 10,000 years or so.) That does not mean that the coal plant *produces* anywhere near as much radioactivity as a nuclear plant. If you want a demonstration, I'll go stand in a room full of unshielded barrels of coal ash and CO2 for 12 hours, and you go stand in a room full of unshielded spent fuel rods for 12 hours. We'll see which of us is able to walk back out.

Nuclear power has problems - but they are all solvable within our technological reach.

With current technology, nuclear power will not put a serious dent in world energy use before we run out of fissionable uranium. If nuclear power is to be the answer to the world's energy needs, we will have to switch over to using breeder reactors almost exclusively. This technology hasn't exactly had a great track record in the real world; it would need a huge amount of work get safe breeder reactors producing power in quantities an order of magnitude greater than current simpler nuclear technologies. In fact, I assert that such a feat is no more feasible than the other technologies you brush off as being too hard or immature.

Re:Umm....

[some_hoser]

When comparing reactor powers, you really need to make sure you know what convention they are using when they say power - thermal power, or electric power? The thermal power of a plant is usually about 3x the electric. A 1000 MW (electric) plant runs at about 3000 MW (thermal). In the field they'll say MWe or MWt. A 60MWe reactor will be about the same as a 180MWt reactor. Another point is that on the nuclear powered ships, so cut down on space they have to use small (in terms of volume) reactors, and they use fairly highly enriched uranium (up to 90%), so the pressure inside gets much higher, and so they are more dangerous that conventional reactors. On a large barge, however, they have less space constraints so could go for a less energy dense and safer reactor.

Re:Safety A few numbers...

[davidsyes]

Umm, the CARRIERS have 2 reactors, each of which can supply enough megawatts to cities of around 20,000 people, even back in the 70's. Maybe they can provide juice to more nowadays. (CVAN-65/CVN-65 Enterprise has **8**, but probaly only 4 to 6 at any time are up and running with maybe 2 on hot-standby and the other to in some other unpublished state of readiness due to the sheere expense of recoring the -65.)

1,000 people in the crew? Try some 3,800 crew and 2,200-2,800 in the air wing, plus the Marines detachment and any "riders" (CIA types, spooks, foreign observers, etc...) and you're talking about 6,000 people.

Even the SSN (fast attack and boomers/nuke missile) boats could provide power to tens of thousands if the right shore hookups are provided for on the pier.

However, this probably isn't an ideal situation as shipboard power reactors are meant to deliver power QUIETLY in a small space, and this imposes limitations on power output and other things land-based reactor operators might not be burdened with. There are very real limitations, other than their being military-grade reactors with any number of issues such as security, secrecy, and more. Otherwise, the dozens from the Thresher/Scorpion class, Tullibe, Skipjack, LA and some of the Ohio boats could have been floated and used for power. However, the oil industry would have balked and probably would have funded the eco-guardians.

Then, the eco-guardians would whip out all the studies indicating that disrupted and elevated thermal gradients have been and would continue to ruin fish spawning sites, kill off plankton, algae, seaweed and other aquatic life along the coastlines (if the plants are submerged and tethered). And on and on and on....

Re:Nuclear isn't necessarily scary

[flyingfsck]

Yup, one can safely chew and swallow plutonium (some crazy scientist actually did that as a demonstration). The only damage will be to your teeth. It would be like chewing on a steel nail. With a half life of 25000 years, plutonium doesn't radiate, so the main danger is that it is a little poisonous, but to do anything, it needs to dissolve and being a solid metal, that doesn't happen easily, so if you swallow a plutonium pellet, it will pass through your body quite harmlessly. Compared to that, the liquid mercury is much worse and we eat mercury all the time in the form of salmon, tuna and dental fillings... It is the schtuff with short half lives that are problematic and since they decay rapidly, they become less problematic rather quickly - a self correcting problem. The real danger of a nuclear power plant lies in the Chernobyl type of fire, where the whole place goes up in smoke, creating a huge mess. This risk is reduced by building the reactors differently. Chernobyl was a carbon mederated reactor, so the obvious solution is to eliminate the carbon from the reactor design and modern reactors don't use carbon, for this very reason.

Re:Nuclear isn't necessarily scary

[WindBourne]

There is no power source that you will make everyone happy. Crazy environmentalists don't like wind power

Do you want to know why we have difficulties getting things done in the USA?

1. Because one crazy group of ppl are busy accusing the other side of being crazy. Sadly, we are now so polarized on issue that we are stymied from getting anything done. My suggestion is that if you want to get things done on this, quite calling the other side crazy. Environmentalist have a point. But even with that said, we have to pick our poison. Time to go for Nukes and Alternatives.
2. One side of the issue is saying that we need nukes, but are busy killing funding for it while lowering taxes on Oil research. The gist is, look directly at our crazy policies. Cuts to SERI while increasing research and tax cuts into Oil.

Once the above stops and we offer tax cuts for nukes and alternatives, then we will see it take off. Until then, we will continue to support Haliburton.

BTW, the biggest fighters of the wind power occured back east on some rich island that is LOADED with republicans. They are not crazy environmentalists. Oh, the other time was one place in California where the site was killing a number of endangered birds. But by simply chosing a different site, those wascally environmentalist were all happy. But the rich republicans back east still are not happy.

Re:Nuclear isn't necessarily scary

[thogard]

Thanks to the fine people at greenpeace, its illegal to do research on splitting the waste into short term waste and reusable fuel. Since no one can do any research or refine it, it just sits there being the boogeyman. While the pools do get warm, they aren't providing enough heat to be useful.

Re:Nuclear isn't necessarily scary

[Anonymous Coward]

Considering France has over 10 times the population and 24 times the area of Massachusetts I don't think that's a problem.

Re:Safety

[frdmfghtr]

Umm... this is a slightly different scale of power generation. Those ships and submarines which are nuclear powered have really small reactors. The power (and more importantly pressure) generated in a small Navy sub reactor is "small" compared to this beast. We're talking about TWO full scale reactors on a barge.

Yes, this is a change in scale, but in the other direction...Naval reactor plants are BIGGER than these two plants, power-wise. The S6G plant in the Los Angeles-class subs alone is more powerful than these two plants. While I've never worked on this particular plant, I don't doubt what wikipedia has to say about it.

S6G: http://en.wikipedia.org/wiki/S6G_reactor [wikipedia.org]

I DO have extensive experience operating older S5W reactor plants, and while I'm not about to give specs on it, I will say that it cranked out more power than one of these proposed floating plants.

As far as an aircraft carrier goes, the typical crew complement is 5000...and it can move in excess fo 30 knots. The electrical load ALONE is 32 MW, not to mention the power needed to drive 95,000 tons through the water at 30+ knots.

In short...these barges are small compared to Naval reactor plants.

Re:No accidents?!?

[treeves]

I agree with the *real* officer (NUPOC = NUclear Power Officer *Candidate*) and I also call BS on the story about transferring 500 gallons of reactor coolant to a sub tender in Groton. I was an ELT (Engineering Laboratory Technician) aboard a nuclear submarine, that, part of the time I was on her, was stationed in Groton (New London Submarine Base). ELTs are the enlisted guys who do the steam plant and reactor plant water chemistry analyses. I am certain that there is no reason take reactor coolant out of the primary loop and move it to the tender (and lots of reasons not to!). The only time that sort of thing would be done is during a refueling overhaul, in a shipyard. A boat in Groton would go to Portsmouth (NH) Naval Shipyard for that. The boat I was on had a 78 MW S5W reactor plant. 120MW is not that impressive especially when you don't have the space constraints of a submarine reactor compartment.

Re:Umm....

[Anonymous Coward]

The number that everyone is using appears to be from the shaft horsepower output of the Nimitz class carriers. This is obviously convertable into MWe.

Re:Umm....

[confused one]

for what it's worth, the Enterprise was overhauled a few years back... and they replaced the 8 smaller reactors with 2 larger reactors, to bring it up to the same equipment standard as the Nimitz class. (I know this because I live within a few miles of Newport News Shipyard, where they did the work).

Re:Scary?

[steve_bryan]

...and limited [nuclear] fuel supply...

Is that the sound of a knee jerking or have you actually bothered to check? Here is a reference [stanford.edu] that indicates that the uranium supply (economically recoverable) would last billions of years though it does not assume exponential growth or anything similar. It does assume breeder reactor technology. In other words we would have to worry more about the Sun burning out first.

Re:Nuclear isn't necessarily scary

[ralphbecket]

Look at this web site: http://www.nei.org/index.asp?catnum=3&catid=746 [nei.org]

You should also look into the risks associated with large chemical plants. Some of the compounds used in bulk in large-scale industrial chemistry are frighteningly toxic: a worst case scenario would be on a par with an extreme nuclear accident.

I quote from the site above:

The NRC must approve containers used to transport used nuclear fuel. Before the agency certifies container designs, the containers must meet rigorous engineering and safety criteria. In addition, the container designs must be able to pass a sequence of hypothetical accident tests involving forces greater than the containers would experience in actual accidents.

These test conditions have included:

        a 30-foot free fall onto an unyielding surface, which would be equivalent to a head-on crash at 120 mph into a concrete bridge abutment

        a puncture test allowing the container to fall 40 inches onto a steel rod six inches in diameter

        a 30-minute exposure to fire at 1,475 degrees Fahrenheit that engulfs the entire container

        submerging of the same container under three feet of water for eight hours.

Containers also are subject to separate testing under 200 meters of water for eight hours.

In addition to the tests required for NRC certification, engineers and scientists at Sandia National Laboratories in New Mexico conducted a wide range of tests on used nuclear fuel transportation containers in the 1970s and 1980s. These tests included:

        running a flatbed tractor-trailer carrying a container into a concrete wall at 84 mph

        placing a container on a rail car that drove into a concrete wall at 81 mph

        placing a container on a tractor-trailer broadsided by a train locomotive traveling at 80 mph.

In all cases, post-crash assessments showed that the containers, although slightly dented and charred, would not have released their contents.

The NRC also conducted a study in 1987 to evaluate further the ability of used fuel transport containers to withstand real accidents. Using data from severe accidents of all kinds, the NRC concluded that transport containers designed to NRC requirements would withstand actual accidents.

Other Sandia tests evaluated a terrorist attack, subjecting a container to a device 30 times more powerful than a typical anti-tank weapon. The test resulted in a quarter-inch-diameter hole through the primary containment wall.

The NRC estimates that such a hole would have resulted in the release of less than 10 grams--about one-third of an ounce--of used fuel.

In combination with actual testing, transportation container manufacturers use computer programs and scale models to evaluate the containers' protective capabilities and verify--with a substantial margin of safety--that the containers meet NRC requirements.

NRC regulations also require the establishment of a security plan to ship used nuclear fuel safely to the used fuel repository at Yucca Mountain, Nev., and implementation of this plan before shipments begin. The NRC will track and monitor these shipments carefully over the entire route. The agency must review and approve the plan and procedures to protect against radiological sabotage or theft in advance.

Re:Umm....

[confused one]

oops, apparently I was wrong... this may have been planned at one point but didnt' happen. So much for local knowledge...

Also note the difference between commercial vs. mi

[Anonymous Coward]

Didn't see a post commenting about this (maybe i'm just mistaken perhaps).

Civilian/commercial reactors are designed not only to avoid meltdowns but to make it impossible to achieve critical mass. They use low % enriched fuel and, usually, aren't breeders. They swap out fuel regularly and are actually fairly inefficient with regards to their power density.

MILATARY reactors however use a much higher % of enriched fuel. They have a MUCH higher power density. (look at the size of a nuclear plant vs an entire sub). Not sure if mil reactors are breeders, but they're clearly not meant to have partial fuel swaps on a regular basis. As a result of this, milatary reactors DO have the ability to reach critical mass in worst-case situations. While you're not likely to actually get a nuclear explosion you DO have a much greater ability for a horrible melt-down, worst-case, etc. etc. etc.

Civilian/commercial reactors are incredibly safe overall. IMHO we should be building them as fast as we can. Even greenpeace has switched it's opinion! Nuclear waste is recyclable ... except many anti-nuclear groups fight tooth-and-nail against anything to do with nuclear *anything*. Even recycling ... since it potentially creates more nuclear fuel. If everyone would carefully examine their nuke-fear ... they'd realise how silly they are. More people die in a year (hell, probably a month) due to cancer or aids or several other reasons than have died in the history of mankind to nuclear power/weapons/waste/radioactivity.

The first floating reactor - USS Sturgis

[SoLoman33333]

The USS Sturgis, stationed at the Panama Canal. The Department of Energy describes the Sturgis as follows: STURGIS Floating Nuclear Power Plant; Designation MH-1A, Location: Gatun Lake, Canal Zone; Principal nuclear contractor: Martin; Pressurized water reactor, Capacity: 10,000 net kW(e), Authorized 45,000 kW(t), Initial criticality, 1967; Shutdown (permanently), 1976. The vessel provided power to the Canal Zone. It was the first floating nuclear power plant and, for nearly three decades, appeared to be the last. In 2008, the Russians plan to bring on line the next floating nuclear power plant.

Re:Why

[kahrytan]

This device works 24/76, with or without the sun.

SolarMission's solar thermal power station will generate electricity 24-hours a day. The power station will be at its most efficient on hot days when energy is most needed and peak prices are paid for electricity. Innovative design will enable the power station to store heat and continue to generate energy during the night. This special feature enhances the commercial viability of the power station and gives SolarMission a consistent competitive advantage over other forms of renewable energy generation.

To correct original reply. It is 20.25 square miles.

Tower: 3000 feet high, 400 feet Diameter
Concrete: 750,000 cubic yards
Collector: 3.5 miles diameter (30 million square yards) glass/polycarbonate/plastic film
Turbines: 32 units x 6.25 MegaWatt
Land: 20.25 square miles (4.5 x 4.5)
Output: 200 MegaWatts (200,000 households)

Re:Safety

[Anonymous Coward]

Okay, great... Let's do a back-of-the-envelope calculation here:

1. Mass of reactor pile: ca. 1000 kg
2. Number of reactors: 2
3. Mass of entire facility, containment structures, etc: less than 1e9 kg (wildly overestimated!)

Let's assume that all of (3) is contaminant, just for fun!

versus

1. Volume of Indian Ocean: 2.9e17 m^3
2. Volume of Atlantic Ocean: 3.5e17 m^3
2. Volume of Pacific Ocean: 6.7e17 m^3

We'll also underestimate the mass at 1000 kg/m^3.

Let's contaminate just the "tiny" Atlantic:

Even diffusion of 1e9 kg contaminants as a solute through 3.5e20 kg ocean as solvent, stir vigorously per your recipe:

something that would diffuse evenly

gives us 2.9e-12 kg/kg, or less than three parts per trillion by mass.

In a cubic metre of Atlantic Ocean water we then get 2.9 micrograms of contaminant.

Let's make it all 238-Uranium, just for fun:

Standard atomic mass: 238.02891 (g/mol)

So, 1kg of 238-U has 4.2 moles, or 2.5e24 atoms per kilogram, or 2.5e15 atoms per microgram, or 7.25e15 atoms per cubic metre of Atlantic Ocean.

238-U has a half-life of 4.468e9 years which is 1.4e17 seconds.

In a cubic metre of the Atlantic ocean, we then have -- to start -- less than one nuclear disintegration per minute.

So, some problems here:

1. It's not going to diffuse evenly, mainly because the fuels are mostly contained in ceramics and metals which are stable under most conditions, and secondly because the ocean does not stir itself very thoroughly or rapidly.

2. The really dangerous stuff with short half lives will act as local toxins until dispersed by the ocean.

3. The much less dangerous stuff will quickly be diluted to the point of harmlessness.

4. There will be *no* contamination beyond a tiny fraction of the ocean, even given maximal stirring.

but

5. It would be *better* to have the contamination disperse evenly and rapidly through the whole ocean, to dilute the contaminants enough to be non-toxic.

how do you contain something that would diffuse evenly

You don't want to! You want to spread it out quickly and evenly. But that's even harder that concentrating it in one location where it's REALLY REALLY toxic instead of diffusing a bit and being merely toxic.

Re:Nuclear isn't necessarily scary

[phayes]

Oh, Bull. The largest proposed windmill project in the eastern USA was the windfarm that was proposed for Cape Cod Bay. Is was killed by opposition from the senior DEMOCRATIC senator from Massachusets: Ted Kennedy.

http://www.boston.com/news/nation/articles/2006/04 /27/kennedy_faces_fight_on_cape_wind/

Re:150 nuclear warheads?

[Anonymous Coward]

I won't even bother signing in.

Ohio class boomers carry 24 Nuclear missiles and an unknown number of nuclear torps. Each missile carries 5 x 475Kt mk5/w88's (reduced from maximum for treaty reasons additional mass dedicated to penetration aids) or up to 14 100Kt mk4/w87's. Hiroshima was around 20Kt so this is some serious counter value throw weight on each boat. That's why they were built, anyone who wants to take out the Us ad better take out every boat or the counterstrike annihilates the attacker, hence the MAD defence policy.

So each Ohio carries upto (24 x 14) 336 warheads not counting non SLBM warheads in the torp rooms. Thats enough sunshine for anyone.