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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

#331

Earlier quoted context omitted.

> Who exactly is investing in this "green gold"? France[0] > If it's so valuable why does no one actually want it, I mean France does... we actually gave them the tech. The reason we stopped is more political. But more people do this than just France, but they are the biggest example since 17% of their entire grid is powered from recycled nuclear. The other reason we don't do it is that it is just cheaper to buy more…

In France this 'success story' led to a state law (2015-992, from 2015, the "loi relative à la transition énergétique pour la croissance verte") stating that the part of nuke-produced electricity must fall to less than 50% in 2025, from 72% then, and that renewables must replace it. In France nuke-power is backed by gas (which produced 10,3% of gridpower in 2017). The sole reactor currently planned (Flamanville-3) is…

I'm unsure what you are suggesting here, so I want to be extra clear about the French policy and current state of affairs. As in stands, France has one of the lowest CO2 emissions per capita[0][1].

No one is saying that we should _only_ use nuclear. Not diversifying your energy portfolio is a terrible idea. France is trying to reduce its dependence upon nuclear (which is a good idea) and replace its fossil fuel infrastructure first. This is because renewables are becoming cheaper. The plan is to have a diversification of nuclear + renewables (which is what pro-nuclear advocates are fighting for). Nuclear serves as a baseload and backbone and is supported by renewables to fill the gap.

You will not find pro-nuclear supporters upset with France's decision to reduce their dependence on nuclear. In fact you will often find support. As battery technology gets better and cheaper and as price of renewables continue to fall you will also find that pro-nuclear advocates will cheer this on.

There is a big misconception that many believe people are arguing nuclear vs renewables or arguing that the grid should be _only_ nuclear. What we are arguing for is nuclear + renewables vs renewables + coal + oil + gas. The reason being that _today_ we have the technology to dramatically reduce our carbon emissions with _current_ technologies. We are looking at countries that already have successful models for emissions and saying "hey, we should do something similar to that, since it clearly works." It would be insane to not look at what models are already successful and try to say that the technologies they use are counter productive. The proof is sitting right there, all you have to do is look. We are arguing for models closer to Sweden (since we, the US, have lots of access to hydro) than were are for France's current system (though their goals would also be a good model to consider).

[0] https://ourworldindata.org/grapher/co-emissions-per-capita?t...

[1] https://www.electricitymap.org/zone/FR?wind=false&solar=fals...

[1.5] Note that Sweden also uses a significant amount of nuclear

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

#332

Earlier quoted context omitted.

This is in no way to disagree with your overall point, but marine cloud brightening looks like it might be a fairly cost-effective solution to climate change. It's unproven, but not an insane gamble either, and it has little risk of second-order consequences if it doesn't work. All that at a cost of single-digit billions per year. https://en.wikipedia.org/wiki/Marine_cloud_brightening#Costs

We have many proven solutions to the climate disaster, including, carbon tax, renewable energy, cleaner and more efficient infrastructure, telecommuting, international agreements, etc. Going after a single unproven solution (yes this includes non-existing types of nuclear energy too) is just magic at this point and it doesn’t work.

All of those reduce emissions but they don't stop them and they don't do anything about the existing already-too-high levels.

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

#333

Earlier quoted context omitted.

> the designers imagined many of the events you mentioned and more Designers are awesome. Sadly they were also unable to find some time in 50 years to raise a wall a few m so it can stand a Tsunami. It seems that the extra scrutiny, was not so extra in the real life when the company will need to allocate real money.

The event you are referring to was also a freak event. The Tohoku earthquake was the 4th largest _ever_ recorded and the largest ever recorded in Japan (by 0.2M, it is a log scale btw). The closest earthquake to that, in the region, in the previous 100 years was 0.7M lower (and the 6th largest ever recorded, in the area). The Tohoku earthquake also resulted in one of the largest tsunamis ever recorded. We should note…

There’s no free lunch but wind and solar are a hell of a lot cheaper than this.

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

#334
"The design is based on Multi-Application Small Light Water Reactor developed at Oregon State University in the early 2000s. NuScale is a natural circulation light water reactor with the reactor core and helical coil steam generators located in a common reactor vessel in a cylindrical steel containment. The reactor vessel containment module is submerged in water in the reactor building safety related pool, which is also the ultimate heat sink for the reactor. The pool portion of the reactor building is located below grade. The reactor building is designed to uphold 12 SMRs. Each NuScale SMR has a rated thermal output of 160 MWt and electrical output of 50 MWe, yielding a total capacity of 600 MWe for 12 SMRs."

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

#335

Earlier quoted context omitted.

We could dump it into the ocean and not worry about it. There's so much cooling capacity and radiation shielding in the oceans alone that we'd never run out of space, so all of the current disposal strategies are way above and beyond what's needed. Containment is solved problem. It's important to note that other energy types also produce waste. For example, coal ash is incredibly toxic and hard to dispose of, and we…

Another option which is completely safe and permanent* is drilling a borehole few km down and dumping the waste there. It's not coming back no matter what. The research done into it shows that "only" 800 boreholes would be required to store literally all nuclear waste ever produced. https://en.wikipedia.org/wiki/Deep_borehole_disposal *to a point where it was actually brought up as a negative, because if we ever want…

> It's not coming back no matter what

If you can drill down to put it in, can't you also drill down (or use the same hole) to get it out?

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

#336
post #251

Earlier quoted context omitted.

Leak to where? It's below grade and it's not under any pressure greater than atmospheric.

The elephants foot in Chernobyl was so hot that melted the concrete and dug into the soil. Is this pool bottom impossible to melt?

Chernobyl was an ancient design that didn't have many safeguards. This one had safety built in from the start, and it's smol and can be contained easily.

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

#338
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.

A small town could probably use one of these, however I don't think farmer Joe and 3 or 4 of his neighbors are going to be able to afford one of these to keep the electric smokers going for thanksgiving...

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

#339
post #139

Earlier quoted context omitted.

> 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.)

Does it count that a Navy man was killed at SL-1? https://en.wikipedia.org/wiki/SL-1 https://www.findagrave.com/memorial/67718734/richard-carlton...

Relative to how many people die every year from wood and coal smoke? I would say it doesn't count in a relative sense.

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

#340
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.

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…

It kills me that people keep not factoring in long term damage to the earth when they figure out how much energy costs.
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