Using nuclear boats for disaster relief

BW,
I can provide some input on this, but I'm a bit wary of providing specifics. AC Power generation via steam turbines is pretty significant and is generally equivalent to industrial 480 vac/60hz. No secret there. The biggest problem is the logistics of getting the power off the ship and into the grid. Shore power connections for any marine vessel are pretty much based on power demand while in a standby condition, so are not capable of full power flow, but >1000 amps could be easily provided.

Nuclear reactors, both civilian and naval, do not use a significant amount of water once the system is full after initial construction. They are closed loop systems, very similar to a radiator cooling system for a vehicle. That being said, all major water borne vessels have the ability to produce potable water from seawater. Different vessels obviously have different capacities, based on equipment needs and manning as much as anything else. Even the smallest water generation plants can provide thousands to tens of thousands of gallons a day. It's easy to fill a tank and then pressurize it to force water to flow through a hose and off the vessel.

Civilian and naval nuclear reactors reject heat to a steam generation system, which has it's own separate closed water system. Imagine the radiator again, except this time, the engine runs hot enough that the radiator stays at 250 degrees. Instead of air cooling the radiator, you have the radiator enclosed in a tank of water, which constantly boils like a coffee pot. The tank has a pipe on the top that allows steam to pass to a turbine generator. The steam spins the turbine, which turns a generator (think of a windmill). After the steam is depleted of energy, it condenses to water again and is pumped back into the tank in a never ending cycle. Only minor amounts of makeup water are needed to keep this loop full. The only additional cooling water needed is to provide cooling to any steam that hasn't condensed after passing through the turbine. This isn't enough to cause a significant water heating issue at the power levels we're talking about and the dilution rates from the surrounding water. Commercial reactors that operate at 98% of capacity 24/7 are a different story.

It would be interesting if some day we decided to take a boat scheduled for decommissioning and instead convert it to a disaster relief vessel. THAT would be a pretty kick-a** vessel, as it could be specialized for the application.

 

Asked....and most excellently answered above.

A decommissioned bird-farm (or even an active one) is a much better disaster relief platform.....but there are other auxiliary platforms that can serve as well.

Unfortunately.....we're down to 10 CVNs active if memory serves.
I know.
Most people count 11, but one or two are always in the yard for maintenance and upgrades.

The USS Enterprise was recently struck from the register and is now being 'de-fueled' and since she was built in the 50s that's probably appropriate, but the first of the Nimitz class CVNs (Nimitz herself) is slated to go off-line in 2022-ish.
One can imagine short cycling a CVN out of service, removing all of the offensive armament, painting them white, and having a platform that can serve VERY admirably if not terribly economically as a disaster relief platform.
Her reactors are a generation newer than Enterprise's, and since there would be no need for steam cats, her water generating abilities would be impressive.

The USNS Mercy class of hospital ships serve as a good model for the advantages and disadvantages of re-purposing a ship to do different and better things.....appropriate since Comfort is en route to PR as I type this.
Mercy and Comfort used to be (of all things!) oil tankers, and some of the challenges in converting them into 1,000 bed floating hospitals specializing in providing trauma care in expeditionary conditions required some unfortunate compromises.

Fun Fact:
Hospital ships have no offensive armament, and attacking one is a de facto war-crime, yet Comfort has a Combat Action Ribbon to her credit.
I'll bet there is an interesting story about that!

 

The Russians are already building nuclear ships for the sole purpose of providing power to a city. Though I think barge is a more accurate term.
Russian floating nuclear power station - Wikipedia

As for a purpose built, or reassigned military, ship for disaster relief, that would probably generate more goodwill for the US than building another warship.

 

Keyword: River.
That's a pretty big heat sink.

I've tied up at Roosevelt Roads and at the piers closer to the city in SJ.....and AGW notwithstanding the boat never really had much of a problem with waste heat - although my anecdotal experiences were in situations where we were not supplying ________ worth of shore power.
Even with the ravages of climate change, SSTs are only in the 80's on the surface, and one presumes that 25' down they're a little cooler.

 

It's been a bunch of years, but I'm pretty sure the seawater delta T of a condenser is only a couple/few degrees. Using a naval ship as an emergency power source for off-hull loads is like using a prius HV battery to operate a radio. The amount of % capacity used would be extremely low, all temperatures/flows/etc would reflect that. Remember, civilian plants are operating at near full design capacity their entire life. They have to be designed to control that heat/waste generation 24/7. The only time a mobile reactor will ever hit near full capacity (which can sometimes be adjusted for by parallax error, I'm sure ETC knows what I mean) is when the main engines are wide open.

 

LOL....

I remember when Engineering used to make reports following the usual drills that propulsion was "Unlimited."
Once.....our skipper responded by saying:
"Very Well.......HELM!!! All ahead flank, Maneuvering, make turns for Two Hundred knots!!" (**)



(**) In the interest of security, I point out that while this folksy anecdote is quite true, I changed the actual number somewhat.
It was intended by the skipper as satire even though the order was logged and signed in the deck log.....and following this the official report to control was changed somewhat following engineering casualties.
US Submarines may or may not actually be capable of speeds in excess of even 100 miles per hour.....

Yes.....I know.
It was a long walk for a short punch line.....

I remember it well because US Navy nukes are usually quite humorless while they are on the clock......which explains their peerless safety record.

Just to put a bow on all of this, I would have NO HEARTBURN with increasing FEMA's operating budget enough to back-haul an active CVN (carrier) and use it for disaster relief.....or building one from the keel-up.

Mercy and Comfort need to be replaced, and one of their more glaring disadvantages is being highlighted right now by the long transit time from Sand Dog to Rosey.

Not as much of a problem with a different hull......

 

Knock, knock . . .excuse me sir, you need to come with us. . . . .

Besides, it was really 300 mph.

 

Cavitation damage....no comment.

Depth gauges......very plausible.

I've heard a lot of sea stories about isolated (or.... non-isolated) shallow and/or deep depth gauges, and the reason for this is that waaaaaaaaaaaaaay back when submarines did not have porcelain shi......er (*) commodes they primarily used mechanical gauges to register keel depth.......because.......they're mechanical.
They work when the lights go out.
They work when hydraulics fail.
They do NOT work when humans fail to line them up properly, which is why submarines are more anal about checklists than airdales....because they have been doing them longer, and NOT doing them usually results in the same kind of memorial services....

The kind with nothing much left to bury.

Depth gauges work (as one might imagine) by knocking a hole in the pressure hull and running a small but rather thick walled pipe all the way up to the gauge where the drivers are.
Since the people inside the pressure hull want most of the water to stay on the other side of the hull, all such piping (or hull penetrations) have at least one isolation valve, and sometimes (usually) more than one.....because.......defication occurs.

SO.....
The reason you have shallow and deep depth gauges is that when you're near periscope depth. feet MATTER more, and so you need a fine-scale gauge when operating close to the surface, but since there's limited space and you don't want a gauge the size of a beach ball cluttering up the instrument panel, there are two gauges..........actually, a lot more than two gauges including one that went click-click-click......as you went up or down. But the ship's control party might or might not be distracted by other evolutions in progress (or bone grinding fatigue, on the mid-watch) and the gauges in front of the three people actually driving the boat have been known not to have been lined up properly.
I personally may or may not know of at least one boat that broached when ordered depth was much deeper.....and I personally may or may not know of at least one boat that sloooowly departed their safe operating envelope in the other direction followed somewhat later by a frantic "Whiskey Tango FOXTROT???!!!!?? call from the torpedo room....(they have seawater pressure gauges and somebody did the math......)

Oh yes.
VERY Plausible!!!

Sea Stories sometimes vary little from a fairy tale but sometimes???
They're actually true.
There's a famous line that fairy tales are different only because they always begin with.....Once Upon A Time.

 

A C-130 driver once told me about a C-5 flying over NYC(pre-9/11) having a sudden auto-pilot failure that put the plane through a split S before diving towards the heart of the city. The pilots were lucky or good that day, and the plane was retired after landing.

 

I do believe ETC is referencing the USS Greenling SSN 614 (I was on the 606 and 719) .....better known as the greenthing. Google search will provide some blogs that discuss this event in generalities. But, I do know that the times I passed by that boat, you could see the stress the hull plates endured. We used to joke about it every time we saw it, but you know those guys dropped some bricks that day.....remember. seawater pressure is 44 psi per 100 feet of depth. I believe the standard military supplied public info back in my days was that our submarines are capable of operating at depths exceeding 400 ft. Looks like this may have been changed to 800 ft and is easily found online.

The below info is from wikipedia, I make no claims one way or the other as to its accuracy.

World War II German U-boats generally had collapse depths in the range of 200 to 280 metres (660 to 920 feet). Modern nuclear attack submarines like the American Seawolf class are estimated to have a test depth of 490 m (1,600 ft), which would imply (see above) a collapse depth of 730 m (2,400 ft).

 

Under English law, using this sort of ship to provide electricity would be assault and battery.

 

This statement is absolutely true - and that's a no shi**er...

 

You got a charge out of that, didn't you?

 

It is important for me to be able to comment on current affairs.

 

Please enlighten me. None of my Airedales would ever sit still long enough to check a list.

Posted via the PriusChat mobile app.

 

The problem in PR is that the electrical infrastructure has been essentially destroyed. Putting energy into the grid is not going to help if the distribution system is broken. Rather than nuclear powered electric generators, wouldn't it be a lot easier, and cheaper, to just get diesel and gasoline to the places that have generators, and generators to the places that need them? I think that cooling the reactors while at a dock is more of a problem than it seems. We switched to shore power immediately upon docking.