Why Aren't Cruise Ships Nuclear Powered?

With the price of fuel, and the size of these gigantic cruise ships, why are they not nuclear powered in the same way the submarines and aircraft carriers are nuclear powered.

The only reason I could consider is a potential security issue, but are there other issues?

Seems like this move would conserve an astronomical amount of fuel.

Nuclear power has a bad reputation (mostly undeserved) with which the cruise industry would rather not be associated. Some ports also have declared that they will not accept nuclear-powered vessels - others haven’t banned them, but are under pressure to do so (New Zealand seems to be a leading example of this trend).

A nuclear power plant will be very expensive to design and install. Nuclear fuel ain’t cheap either. Its operation will require more and better-trained staff, which will significantly offset the advantage of not burning fossil fuels.

The main advantage of nuclear-powered ships is not lower costs, but far greater freedom from the need for frequent refueling. In the case of submarines, there is also the huge advantage of not needing air.

This is why I love this place because a good answer is always a click away.

Thanks for the replies, and Happy Happy 2005.

Regards

Well, it’s an idea not all that unheard of. There was the nuclear ship Savannah, which was a freighter that carried passengers. I don’t know if there was ever a dedicated nuclear powered cruise ship; a quick search didn’t turn one up.

In addition, SOLAS, the International Maritime Organization’s convention for safety of life at sea, even has a chapter of regulations dedicated to nuclear powered ships, and even provides for inspection procedure and certification of nuclear powered passenger ships.

Personally speaking, here’s a few point to ponder:
[ul]As mentioned by SavageNarce, there will be ports, even countries, that will probably outright ban such a ship from entering.
[/ul]
[ul]Vacationers, who are more concerned with their own happiness and safety, than the fiscal policies and economics of a cruise ship company, would probably shy away from riding around on a “nuke” ship.[/ul]
[ul]The ship would be a lightning rod for protesters, concerned port officials and security personnel[/ul]
[ul]The cruise ship companies are making very nice profits right now with their existing fleets, so why mess with that?[/ul]

All in all, it would probably just be way more trouble than it’s worth.

In addition, there’s the pesky question of disposing the worn-out reactor at the end of it’s service life. Navy vessels get special handling because they’re considered indispensable for national security, but a privately owned vessel might have a hell of a time finding a grave for it’s reactor. The Savannah was a fiasco from a cost and legal liability viewpoint.

On a nuclear submarine or aircraft carrier, everyone onboard is (presumably) specially trained for nuclear rector problems. I doubt weekly duck and cover drills are likely to be too popular with the average cruise ship vacationer.

1/ Cruise ships aren’t large, comparatively.

2/ Even large merchant ships aren’t nuclear powered

3/ Cruise ships travel to nice ports, reefs, holiday destinations, national parks, fiordlands etc. Large merchant ships travel (very largely) to coalports, oil terminals (often not even in sight of land) and grubby container terminals. Even the latter cop an enormous negative public reaction to the slightest hint of pollution or the possibility of it. Nuclear powered ships stooging around in conservation areas? Forgeddaboudit.

In short, if large merchants ships haven’t gone nuclear, cruise ships ain’t going to any time soon.

On the other hand, a nuclear-powered cruise ship sounds like the perfect plot device for the next James Bond Flick, Vaguely Stupid Title.

My background: I used to live on a nuclear powered cruise ship. The amenities weren’t much to write home about, the ports we visited were definitely second rate, and food, frankly, sucked. :smiley: It was run by the US Navy, and it’s name was the USS Virginia.

I was one of the radiological control technicians on board and for my last two years aboard I was the man in charge of giving the all-hands radcon training to all newly reporting personnel, and to everyone who wasn’t nuclear trained at least once a year. Based on what I taught I can assure you: a cruise ship wouldn’t need much training of it’s passengers for the basics of the safety concerns they have to be aware of aboard a nuclear powered vessel. Certainly it could easily be combined with the training they’re supposed to get for lifeboat and fire drills. Unfortunately, a cursory look at historical cruise ship disasters going all the way back to the SS Morrow Castle make it clear that the majority of cruise lines don’t want to annoy their passengers with this training if they can possible avoid it.

More to the point, using a Pressurized Water Reactor (The kind used by the US and Russian navies) requires a very manpower intensive crew. As a measuring stick, the Virginia class cruisers and the Ticonderoga class cruisers are very similar ships, with similar missions, displacement, and weaponry. A Ticonderoga class cruiser has a crew of approximately 400; while I was aboard Virginia we rarely had under 600. The main difference in the crew sizes was simply the engineering plants. Some of it was, yes, a larger engineering crew meant that there was a need for additional cooks, and other supporting sailors; another factor was that while we were heavier than a Ticonderoga class ship, we had more space than they did, too - so we had goodies they didn’t have. But the basic difference was the manpower requirements for the engineering plants. Cruise ships want to keep their overhead down as much as possible. If they can get adequate efficiency by using large diesel engines, which can be monitored by one or two watchstanders, why pay for 13 or 15 watchstanders instead? That’s one reason modern cruise ships are diesel powered, not oil or coal fired steam plants like in the heyday of the cruise ship.

Another reason going to overhead, is that steam plants are very maintenance instensive. Corrosion rates are controlled by three things: The reactants available, the presense or absense of liquid water, and temperature. Steam plants are hot, and use steam, so there’s a lot of water running through the piping. Let any contaminants get into that water and you can have metal getting eaten through faster than you may imagine. Chloride ions, very common in seawater, are particularly damaging. All this means that a steam plant needs relatively frequent maintenance, and replacement of parts. The diesel plants being used, don’t have this problem. They still wear out, but no where near as quickly.

Next is the very real problem with the public perception of the safety or lack of it for nuclear power. Frankly, I’d rather live next to a nuclear power plant than next to an oil refinery. But not many share my prejudices. :smiley: It would be a hard sell, and even then it would severely limit where you could go - the fact that the ship in question would be civilian might open up some ports currently closed to nuclear warships, but I wouldn’t want to count on that.

Finally, nuclear power has a couple of long term difficulties. First off neutron fluxes do bad things to metals. Over a period of time they make the metal crystals more brittle, and that gets to be a real hassle. And puts an absolute upper limit on the lifetime for one’s plant. Secondly is the whole disposal issue for reactor waste. I understand the political decision to not reprocess spent fuel, but don’t completely agree with it.

Now, none of these problems are what I’d consider insurmountable - going to a pebblebed reactor, using helium gas as the transfer fluid - would reduce both manpower and maintenance costs. The problems are just that at the moment, no one (that I know of) has built a pebble bed reactor, in spite of the many good things to be said about them. But why do all that, when diesel is going to be easier to sell to the customers anyways? And diesel techs are cheaper than rad sponges.

Just a small amendment to OtakuLoki’s excellent points. As he says, deisel mechanics are much cheaper. The training that the cruise line would need to certify for nuke operations would be expensive, and the wages commanded by those with this specialised training would be much higher (supply and demand). The economics of a cruise line depend on having minimal crew wages. In fact, many of the workers make much less that US minimum wage. They can do this because they hire foreign workers, and have foreign registration.

In short Carnival would go bankrupt very quickly if they tried this today. Never mind the capital costs of the nuke plant.

Let’s not forget that on a Naval vessel there are trained, disciplined people who face severe punishment for unauthorized entry of a reactor space. On a criuse ship you have anyone who will pay the ticket price. Unlimited proximity to a nuclear reactor by John Q. Vacationer would be a bad thing, and it would be an invitation for some sort of terrorist attack.

Maybe the cruise lines could use nuclear power to pull a New Coke thing - launch a fleet of shiny nuclear cruise ships, sit for a couple of years watching the public hate them, then relaunch their old ships, “powered by good old safe, dependable, clean diesel that you always loved so much”.

I assume you’re not implying that passengers have free access to the engineering spaces of a cruise ship, because they don’t. In July 2004, the International Ship and Port Faciltiy Security Code (ISPS) went into effect for (basically) SOLAS vessels. These regulations were in response to 9/11, and are designed to tighten up security at maritime facilities and aboard ship by mandating certain practices and procedures. The engineering spaces are “controlled areas”, and access to these spaces must be guarded against unauthorized access. The same goes for the bridge, steering spaces, anywhere “vital”. I can tell you from experience, that cruise ships take these regulations more seriously than other merchant vessels.

Prior to 7/04, cruise ships already had similiar security measures in place. In fact, cruise ships calling on U.S. ports were required to have their security plans reviewed and approved by CGHQ, else they were not allowed to call here.

Nobody cares about cruise ship security like the cruise ship industry; they already knew they were a likely terrorist target.

However, if you’re saying that just having would be terrorists on board, then yeah, that is inviting disaster. I’m sure that we’d all agree that a determined, well trained group of individuals would be able to bypass existing security measures, and eventually be able to breach security perimeters given time and tool and weapon. Regardless of the outcome, it wouldn’t be pretty. Fortunately, I can’t imagine a cruise ship company willing to risk it.

I’m saying that a nuclear reactor on a mobile, general public accessible platform would be madness. Besides, to cause incredibly high levels of contamination you wouldn’t even need to get to the reactor itself, just something like the heat exchanger.

Yeah - I’m inclined to agree with you on that point, especially nowadays.

That’s why I mentioned the pebble bed reactor plans. Unlike PWR designs, they don’t activate the heat transfer medium (Well, not appreciably…) and helium gas doesn’t carry wear and corrosion products through the core to be activated themselves. Pebble bed reactors are also inherently stable, one of the new generation of reactors that can’t be made to melt down, even if you take all the coolant out of the core at once. I don’t know how they’re moderated off the top of my head, though, so it may be possible to take them prompt critical - I’m not sure whether they’re a fast or thermally controlled design.

I’m not advocating the use of nuclear power in cruise ships, just saying that the risks for contamination may be far less than you seem to believe.

(Now, if you want to make the Homeland Security’s favorite nightmare: a dirty bomb, a PWR is juuuuuuust right. sigh Adm. Rickover was a genius, but he also designed his plants to be operated by intelligent, informed, and confident personnel. As such, his plants are not idiot-proof, just very robust.)

This is starting to get really technical, so if anyone wants to continue the discussion I’d be glad to, but we might want to move it over to GD or some other forum. And, I have to admit, in reality I’m a trained technician, not an engineer, let alone a scientist. I can intelligently operate said plants, and discuss the design philosophy behind the one I operated, and some of the gross details of others I’ve read about. That does not make me an expert.

[sailor hijack]So, OtakuLoki, would my time at D1G have helped me find my way around #2 plant on the Virginia? Folks who had served on the Bainbridge and the Long Beach told me that their plants were almost indistinguishable from D1G.[/sailor hijack]

Yeah, from what I hear. We were a D2G plant which AIUI was different mostly in the core properties. I don’t know, myself, since I wasn’t a D1Git, but rather qualled on S3G instead. (Last class of ELT to go through, IIRC) Though, I thought that Long Beach was a C1W plant, not D1G.

[Warning! anecdote]
I travelled on the QEII (although pre-9/11) from Southampton to Tenerife with my (then)boss, who was somewhat unconventional in his methods (for unconventional, read: completely raving bonkers); although I was working on board, I travelled as a passenger.
Once we were through the security/customs/check-in, we boarded the ship by walking up a conveyor where they were loading provisions; we then made our way up through various holds, passages and spaces filled with clanking machinery, to emerge through a panelled door into a passenger gangway on one of the lower accomodation decks. Nobody challenged us at any point; they were all too busy and we strode on as if we knew exactly where we were going.

Of course, I don’t mean to suggest that we’d have such an easy time of it now, and I’m certain that something as important as a nuclear power plant would be under special security anyway; I merely offer this anecdote as a (sort of) counterpoint to the assertion that passengers don’t get to go where they shouldn’t.
The cruise line and the vessel may have policies, rules and procedures (and I’m sure these are much tighter today than they were those few years back), but in the general chaos (and there’s a heck of a lot of this when a ship is in port on one tide and sailing, fully resupplied with all new passengers on the next), not everything always goes according to plan.