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Small nuclear reactors: tiny NuScale reactor gets safety approval

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Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#91

Post by liability »

adrianmonk wrote: post #39
EricE wrote: post #12

This is huge. Not only are micro reactors far more economical, it dramatically reduces the need to maintain a massive nationwide grid and provides flexibility to people in remote areas including greater autonomy. Efficiency should be greater without massive transmission line losses. Might start fewer fires in California too.

I'm not an expert, but I'm not convinced about it reducing the need to maintain a nationwide grid. Nuclear reactors take ages to ramp up and down. It's basically going to be generating the same amount of power 24x7, but demand is going to fluctuate. The more other areas you're connected to, the more opportunity there is to send that power to someone who can use it. Obviously there's a law of diminishing returns at so…

> Nuclear reactors take ages to ramp up and down.

Naval reactors are apparently very fast in this regard, so it's evidently not an inherent property of nuclear power.

(The USN also has an unparalleled record of safely operating reactors; more that 5,000 reactor-years clocked without major incident.)

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#92

Post by epistasis »

rubber_duck wrote: post #23
toomuchtodo wrote: post #16

Earlier quoted context omitted.

The economics are yet to be borne out. I believe the NuScale cost (feel free to correct me if this information is wrong) is still above the cost of renewables and storage [1] but below that of traditional PWRs (684Mw @ $3 billion [2], ~25 cents/kwh [3]), which is competitive in places like Hawaii (which is still relying heavily on diesel fuel for what solar isn't providing) and geographies with limited land or renewa…

Thing is this kind of design benefits massively from economies of scale, same kind of thing that has drawn the price of PV down and other green energy.

Up until recently the "economy of scale" meant massive reactors when it came to nuclear, and small modular reactors were abandoned because people didn't think they could be economical.

We have radically different construction skill sets now than we did in the 1970s, so the economics may be different now, and it could have been that the planners were wrong before.

But I'm any case, until a few of these have shipped, I'm not sure we'll know the true cost.

These are manufactured like airplanes, a few at a time. Whereas solar has massive plants with hundreds of thousands of the same part assembled and shipped. I'm hopeful that they will provide another tool in the fight against climate change, but not super optimistic. There are many many technologies that are at a similar stage of development that could be used instead, such as cheap hydrogen electrolyzers, long-duration storage flow batteries, etc. And if these other techs succeed, they will also help SMR nuclear, assuming SMR nuclear can compete with renewables on cost!

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#93

Post by marshray »

nickik wrote: post #70
marshray wrote: post #42

I think it's disingenuous to argue the economics of nuclear without mentioning: "DOE reported that it faced an estimated $494 billion in future environmental cleanup costs — a liability that roughly tripled during the previous 20 years." https://www.gao.gov/assets/700/696956.pdf

It disingenous of you to argue that all DoE cost from the last 60 years have any implication on a modern nuclear site build. When nuclear started they had no idea how to do things and had to do a lot of things very fast. The waste majority of those cost are not because of civilian nuclear reactor, but rather creation of nuclear weapons. Site cleanup cost are a factor, but not a huge one considering a site can be acti…

Perhaps you'd like to link to some figures for the cost of permanent disposal of commercial waste?

Or were you just planning to let the grandkids deal with that?

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#94

Post by jessaustin »

jabl wrote: post #73
jdeibele wrote: post #69

One thing not addressed is physical security. As pointed out by @adrianmonk it would take many of these tiny reactors to generate the same amount as a typical older reactor. Older reactors are designed like fortresses, supposedly able to take a direct hit by a commercial jet and survive. They have armed guards, etc. It would be interesting to see how they would try to protect these. Typical electrical substations are…

The idea is to put multiple reactors at the same site, not to spread out mini reactors all over the landscape. So the end result would be a powerplant that produces about as much power as a "normal" nuclear power plant, just that it contains many small reactors instead of a few big ones.

This undermines some of the claimed benefits. A bunch of little Fukushima Daiichi reactors in the same location wouldn't have fared any better than the actual Fukushima Daiichi reactor.

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#95

Post by trothamel »

marshray wrote: post #76
acidburnNSA wrote: post #71

Earlier quoted context omitted.

There are good permanent disposal methods available. The deep geologic repository under construction in Finland is probably the best example. More info here: https://whataboutthewaste.com People use "what about the waste" as a reason to not use nuclear. Yet, fossil and renewable biofuel waste is (as mentioned) just dumped into the biosphere where it ends and estimated 8 million lives early per year, according to the…

That option doesn't exist in the US. We have no permanent disposal facilities, not even in the planning stage. https://www.gao.gov/key_issues/disposal_of_highlevel_nuclear...

https://www.wipp.energy.gov/ is one, though that's for government rather than commercial waste.

It's a matter of political will at this point.

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#96

Post by dodobirdlord »

e12e wrote: post #75
acidburnNSA wrote: post #71

Earlier quoted context omitted.

There are good permanent disposal methods available. The deep geologic repository under construction in Finland is probably the best example. More info here: https://whataboutthewaste.com People use "what about the waste" as a reason to not use nuclear. Yet, fossil and renewable biofuel waste is (as mentioned) just dumped into the biosphere where it ends and estimated 8 million lives early per year, according to the…

Unfortunately that doesn't quite solve the problem of getting waste from reactor to storage site.

It’s not really much of a problem. You leave the waste in a cooling pond at the plant for a couple of decades while you wait for all the really threatening stuff to decay, and then drive it where it needs to go in a truck. It’s a bunch of big metal rods in canisters. It can’t really “spill” and if it does you just pick it up and put it back in the truck. Uranium and plutonium are really not very threatening to human life.

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#97

Post by jabl »

sarcasmatwork wrote: post #4

fyi, OSU college has a 1-megawatt research reactor. https://www.oregon.gov/energy/facilities-safety/facilities/P... https://www.corvallisadvocate.com/2012/got-nuke-state-of-the...

A lot of universities around the world have research reactors.

Back when I worked at my alma mater, I could see the reactor building across the yard from the coffee room. Still waiting for that third eye to start growing out of my forehead.

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#98

Post by manfredo »

marshray wrote: post #76
acidburnNSA wrote: post #71

Earlier quoted context omitted.

There are good permanent disposal methods available. The deep geologic repository under construction in Finland is probably the best example. More info here: https://whataboutthewaste.com People use "what about the waste" as a reason to not use nuclear. Yet, fossil and renewable biofuel waste is (as mentioned) just dumped into the biosphere where it ends and estimated 8 million lives early per year, according to the…

That option doesn't exist in the US. We have no permanent disposal facilities, not even in the planning stage. https://www.gao.gov/key_issues/disposal_of_highlevel_nuclear...

We do have a permanent disposal facility built, but congress chose to forbid its operation. This is a self inflicted problem: we don't have a permanent disposal facility because we refuse to use the permanent disposal facility we built.

https://en.m.wikipedia.org/wiki/Yucca_Mountain_nuclear_waste...

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#99

Post by liability »

e12e wrote: post #75
acidburnNSA wrote: post #71

Earlier quoted context omitted.

There are good permanent disposal methods available. The deep geologic repository under construction in Finland is probably the best example. More info here: https://whataboutthewaste.com People use "what about the waste" as a reason to not use nuclear. Yet, fossil and renewable biofuel waste is (as mentioned) just dumped into the biosphere where it ends and estimated 8 million lives early per year, according to the…

Unfortunately that doesn't quite solve the problem of getting waste from reactor to storage site.

Besides the obvious NIMBY problems, are there any problems with sealed casks transported by train?

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#100

Post by natcombs »

jhallenworld wrote: post #52

Here is the NRC website about this reactor: https://www.nrc.gov/reactors/new-reactors/smr/nuscale.html Here is an interesting sub-report: https://www.nrc.gov/docs/ML2022/ML20224A525.pdf Information withheld for security reasons. One item concerns the "ultimate heat sink". What happens when the ultimate heat sink is lost? Well a design assumption is that it is not lost: https://www.nrc.gov/docs/ML2020/ML20205L410.pdf…

>> What happens when the ultimate heat sink is lost?

What's an example event where the ultimate heat sink might be lost?

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