Nuclear Power

I think the biggest reason is the cost. In short, naval reactors do not use the same type of fuel as commercial reactors, so refueling them would make it cost prohibitive.

How so?

Can you (or someone) expand on this a little. This seems an interesting idea.

It has to do with the level of enrichment. Naval reactor use highly enriched uranium to enable a higher power density (and hence make the reactors smaller for the same power output). Commercial fuel uses uranium enriched to ~4% U-235 (96% U-238). Naval fuel is nearly the reverse and this is what drives the cost.

One could refuel a commercial reactor of the same size many times over (somewhere in the 20-30x neighborhood) for the cost of one naval refueling.

Doesn't the more enriched uranium increase the power output of the reactor? So more expensive in, but more power out... would it not eventually pay for itself? Or would it be $1.00-$1.50/kwh versus $.05/kwh (for example)?

A somewhat appropriate way to think of it might be to use a car/gasoline analogy.

For the same car, boosting the octane (increasing the enrichment) does provide additional power. Or for the same power consumption level, you would use less gas. Enriching it does much the same.

The prices are close between a high and low octane, so it isn't completely unreasonable to imagine a car that would run more cost efficient using a more expensive gas.

In the case of enriched uranium, the prices are nowhere near each other (between reactor grade and naval fuels). I'm sure the numbers have changed slightly since I first heard them, but it would be like paying $60/gal for gas. (For electricity, the $1/kW-h is probably not far off)

Thanks for the reply. After I posted, I did as we so often suggest around here and searched the internet. My findings are very close to your explanation.

Might this additional fuel expense be offset by the fact that the equipment is existing, technicians are available to operate and maintain them, procedures exist for acquisition and disposition of ²³⁵U... these sorts of logistics.

You're absolutely right in that there is a great cost benefit in place for all the reasons you cited. Not to mention the "red tape" is done as well.

From a pure cost standpoint, you might be right. However, from what I've learned, the major cost for running a power plant is the fuel, so my gut tells me probably not cost feasible. I guess one would have to just crunch some numbers to be sure.

I can't imagine it would be more expensive than building entirely new reactors.

I'd pay ten bucks just to get tour of one!

Hey guys... have a look at this blog, posted today at CR4.

Somebody is taking your idea!

I'm guessing these are using different fuel than the military reactors.

For some reason this thread never made it into the Daily Digest. It didn't get the kind of discussion I thought it would...

It'd surprise me if they used the same type of fuel that military reactors use. I tried digging briefly into it to find some specific details and didn't turn up anything.

I would have thought quite a few people would have chimed in. I expected the anti-nuke people to rant a bit at the very least. Maybe you could try opening a new discussion to get it in the daily.

If you wanted it on the DD, you should have titled it 'Free Power', or some other well established attention and comment getter.

Regarding different fuel; so what? That is an issue for the engineers, perhaps they are living within the rules about acquisition that are in place. Is changing some of these rules impossible? Make the new power station a military reservation, and secure it. Initialize, startup, and not refuel for 30 years? I like it! I still think this is a discussion-worthy idea... what about doing so in world relief efforts, like Haiti? All of those container houses we discussed need lights.

I can find information about decommissioning the ships, but no information about the reactors... are they re-purposed as a unit for something already? Disassembled and scrapped out? Buried with waste? Is there some reason (or several reasons) these simply cannot be used as you ask?

I was looking forward to some more discussion as well. Oh, well, someone was bound to derail the thread anyway... US military is the devil, nuclear power is the devil...

Maybe I should have titled it "Gravity=Energy=HHO"

Here's a link to a slough of info on Russia's program.

http://www.nti.org/db/nisprofs/russia/naval/technol/reactors.htm

Regarding different fuel... there are alot of concerns. Cost aside, I'd like to point out the level of U-235 enrichment can be to "weapons grade" levels. This makes for a sticky situation. U-235 weapons are simple in design and easy to construct. From the link above the reactor would contain some 115-250 kg of uranium... I don't remember the number exactly, but the minimum amount of material to build a weapon is ~25kg. Divide it out and multiply by the number of proposed reactors sitting offshore and... well, let's hope we can secure them all.

From discussions I've had, I understand the decommissioned plants are cut from the ship (as a whole), filled with concrete, and disposed of (I never got clarification as to whether this meant "deep sixed" or buried. I don't know if it's true or not.

I'd agree the concept is worth exploring though.

Aside from the above, I think one important consideration would be the equipment lifetime. As I understand it, naval system were originally designed with a 30 yr life time in mind. Congress said, 'that's well and good, but we don't have the budget to produce more ships at 30 years.' And magically, we have ships with a 30 year design life extended to 40 years. As with the civilian nuke plants that had their permits extended at the end of design life, naval ones were too. How long do you want to operate a plant that is already 10 years beyond its design lifetime?

Well, the age of the plants is a valid reason to discontinue using them. I had not considered there was a 'Cash for Nuclear Clunkers' program, but every machine does simply wear out.

This is an elemental enough idea that if it were economically feasible, the demand high enough, and the project readily acheivable then someone would have done so by now.

Still thought provoking. Good discussion.

[edit] ChaoticIntellect, I read through your two links. Nicely done. Very informative.

I just found this regarding the naval reactor decom...

http://www.armscontrol.ru/subs/disposal/proe1210.htm

and the life expectancy has expired....can turn out to be very costly.

And the carriers have facilities to offload it nuclear wastes....you didn't know that did you. Try getting the permits for disposal.