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The construction knowledge struggle is real. There are people overseas, particularly in some S. Korean and (yes) Japanese construction managers. The Gen-II LWRs they were building on time and on budget would be perfectly sufficient to stave off global warming. We could as a world decide to have those guys swoop in and re-teach us how it's done if we really decided to. Of course, the whole supply chain has to be ramped up, which is pretty non-trivial.

Hey, it looks like TerraPower at least has some people who share your pet theory [1].

[1] https://www.worldscientific.com/doi/abs/10.1142/978981314899...

Nice! Always happy when my crazy theories are backed up by engineers actually working the problem :).

Honestly, I think for the LWRs in the US, it's more of a financing and risk problem than anything. As I understand it, the two South Carolina LWRs failed mainly because the fracking boom created a glut in natural gas prices. Now no one is willing to make any bets on energy prices 20-years out [2]. Note that I'm not sure if these were Gen-II.

At least from a cost standpoint, building LWRs the way we used to is akin to Space Shuttle launches: Awesome idea 30 years ago, but they match the finance risk profiles of energy markets today.

Re: construction. Funny enough, there's actually a industry-wide skilled construction squeeze in the US right now [1]. After the '07 crash the number of new workers going into construction dropped precipitously. Now when we need skilled project managers there isn't enough to fill demand.

[1] https://www.usnews.com/news/the-report/articles/2018-06-15/t...

[2] https://www.nytimes.com/2017/07/31/climate/nuclear-power-pro...

Space Shuttle launches, looked like an awesome idea 30 years ago but was really stupid already back then...

That supply chain ramp up is going to be more damage done, and at this point to stave off climate change every new plant would need to be primarily used for some sort of carbon capture technology

Naval reactors are very different. They dont, most of them, generate electricity. Thier steam pushes propellers. And they are also self-contained within ships. Getting the power from the reactor to shore is a huge task, the bigger task imho. Naval reactors are also smaller and not as efficient than a civilian reactors. They are biult for different priorities (low manning, variable power, long operation at very low power, decades between refits etc). And they have a failsafe not applicable to a civi reactor near a city: evacuate and sink it to the bottom.

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

Says that the reactor also powers other systems. And sometimes the motor is electric.

Makes sense. Why would you build a nuclear reactor and then only use the steam to power the motor?

Tiny generator compared to overall reactor power. Standard diesel engines also produce far more motive power than electrical capacity.

No comment on the other points but the reactors in the new Ford-class carriers generate electricity, not steam, which is part of the reason those carriers use electric catapult.

Ford’s propulsion is still steam but it generates a tremendous amount of electrical power for its other systems

I believe France’s boomers and the next gen SSBN the US is designing both have electric drive.

Isn’t this a bit of a “if you can dodge a wrench, you can dodge a ball” question though? Electricity generation and direct steam propulsion both drive turbines, the principal of shipboard operation is well proven.

The bigger issue in my mind is that the nuclear powered ships spend a tremendous amount of time in port ( at least compared to the downtime of a land based power station) and then often just sail around bad weather rather than get hammered by it.

That is why i said most. The new trend is towards "all electric" drive. But even there, the power isnt being turnef into clean a/c for general use. The reactor, generator, and electric motor are all a tight unit designed to throttle together.

”the reactors in the new Ford-class carriers generate electricity, not steam”

All nuclear reactors generate steam. That steam then drives a turbine which generates the electricity.

The difference in the Ford class is that the steam turbine is bigger, powering most of the ship’s systems via an electrical bus rather than by piping steam around the ship. This approach reduces complexity and maintenance costs.

High temperature reactors use helium as the coolant can use the brayton cycle turbines instead of steam turbines. https://en.wikipedia.org/wiki/Brayton_cycle

https://en.wikipedia.org/wiki/Very-high-temperature_reactor

I wouldn’t say zero experience:

https://ocw.mit.edu/courses/electrical-engineering-and-compu...

> They dont, most of them, generate electricity.

wat? They most assuredly generate electric power. It's just that the bleed steam the sub needs for electric power is trivial compared to the motive power sent to the main reduction gear. They carry diesel generators for emergency use only.

Diesel? Won't that suck out all the air? Or poison everyone with CO?

Certainly they must be surfaced in order to run the diesel generators. See the "emergency use only" that was part of the sentence the previous poster wrote.

All reactors generate steam.

The steam is used to run generators and provide electricity, as well as run engines that drive screws (propellers are on airplanes).

Naval reactors are smaller than civilian reactors, but are far more efficient and use different fuel.

And "evacuate and sink" isn't an option in a multi billion dollar strategic asset.

> All reactors generate steam.

The Soviet Alfa-class used molten lead-bismuth coolant. (Which was run through a separate steam generator to generate steam, granted).

Though there's no principal reason why steam has to be the working fluid. Supercritical CO2, for instance, has many attractive properties.

> Naval reactors are smaller than civilian reactors, but are far more efficient

Hmm, define "efficient"? Efficient as in conversion of heat to mechanical power? Or use of uranium fuel? Or what?

Props as in...screws? Propeller shafts that drive...screws?

"Screws" is A naval term for a propeller. Technically a propeller could also be a paddle wheel, a jet-drive, or ducted propeller sometimes called a propulsor. Screws are also sometimes called "wheels" by fishers. Everyone has their own terms. Naval people use slang to differentiate themselves from laypersons. I'm in an airforce. We don't take colloquial language so seriously.

No, that's not why we use slang, and a propeller and a screw are actually different.

France did that in the 1980s. France has 58 power reactors, of four basic designs.

I think Russia just launched a floating 70 megawatt nuclear power plant quite recently

https://gizmodo.com/russias-floating-nuclear-power-plant-has...

It's more like what a diesel generator is to a power plant, but it's mobile (has to be towed but transportation is quite cheap). It should get the job done. Sadly only the BRICs (mostly Russia) have small modular reactors in operation or under construction, the rest of them range from conceptual designs to licensing stage. Of those, I liked NuScale's design.

https://en.wikipedia.org/wiki/Small_modular_reactor

I would not want to live near any russian nuclear reactor. Russia's handling of these is extremely poor. Just look at the fate of their nuclear-powered submarines.

http://blogs.reuters.com/great-debate/2014/05/27/russias-nav...

Are you hinting at Kursk? It did not even leak for the year it was laying on seabed.

Example: Germany paid more than 550 million Euro and provided expertise&people to help securing rotting nuclear reactors from Russian submarines:

https://de.rbth.com/wissen-und-technik/79917-russische-atom-...

If Germany invested that amount of money into Russia, you can bet that it was urgent.

Hopefully Russia has shown more care dealing with their Nuclear power plants...

https://www.dw.com/de/russland-entsorgung-von-atom-u-booten-...

http://www.faz.net/aktuell/politik/lager-fuer-alte-atom-u-bo...

All in all the West (!!!) provided many more billions for the safety of those approximately 120-180 (!) nuclear-powered submarines.

https://www.zeit.de/2013/07/Russisches-Polarmeer-Atom-U-Boot...

Pictures:

https://www.bmwi.de/Redaktion/DE/Downloads/A/abruestung-atom...

Russia also has submarines buried at the ground in the arctic sea. Like the K-27 in the early 80s.

https://www.maritime-executive.com/editorials/russia-updates...

Sunken objects:

> 17,000 containers of radioactive waste; 19 ships containing radioactive waste; 14 nuclear reactors, including five that still contain spent nuclear fuel; the K-27 nuclear submarine with its two reactors loaded with nuclear fuel and 735 other pieces of radioactively contaminated heavy machinery.

Would seem to me that there should be a way, with smaller, standardized designs, to pre-fab most of the precision stuff and just assemble it on site. The things that are hard about older designs are the need for very strong, perfectly cast concrete for the high pressure containment vessel, and the high-pressure precision-welded plumbing for the reactor coolant.

The nonradioactive steam handling, turbines and electrical generators should be quite similar to what's used in conventional coal/natural gas plants.

>This makes each one effectively as expensive as the last.

And as dangerous.

Great point. Maybe time for a large dedicated body to cut costs and improve quality.

Yep, the report the podcast mentions (from the breakthrough institute) compares how similar industries (like pharma and spaceflight) manage regulation while still fostering innovation [1]. A lot of the differences are around nuanced things like having clear checkpoints for regulation and points of contact from the regulating bodies.

[1] https://www.greentechmedia.com/articles/read/struggling-nucl...

I sincerely hope you realize oceans are functioning ecosystems and not conveniently located safe zones for nuclear disasters. This is the sort of cavalier attitude toward the nuclear waste and accident problem that permeates nearly every HN thread on this topic — and it comes up a lot.

Add NIMO to the list of social blockage

While we need to be aware of environmental impacts, the same is true of how to mitigate them using existing processes. The French recycle their fuel. Eventually it's not usable in their traditional reactors. They ship the waste to a plant that creates glass logs. The material is then safely stored, as a solid, underground.

The US does a poor job of recycling due to the fact that it listened to the environmentalists and anti-terrorist groups in the 70s. Jimmy Carter was told that recycling was bad for the environment (won't someone think of the children if the train overturns), was not cost effective, and would lead to nuclear proliferation due to terrorists dropping from the sky and stealing the train to Mexico [2].

Now we can recycle, and we can reuse the fuel to breed new fuel sources. If we did this 30 years ago, even just the first half of the last clause, we would not be looking down the barrel of climate change.

1 - https://www.zdnet.com/article/what-france-plans-to-do-with-i...

2 - https://www.forbes.com/sites/realspin/2014/10/01/why-doesnt-...

* Edit a typo thing of the children -> think of the children.

Well, except we would, because the cost of nuclear plants didn't go to zero and still suffers from NIMBY, especially after Three Mile Island.

Which is all a shame given how much better modern designs are.

> (won't someone think of the children if the train overturns)

> proliferation due to terrorists dropping from the sky

This is exactly what I mean by a cavalier attitude towards these problems. It is dismissive, uses manipulative phrasing like the president "was told" that removes his agency, paints environmentalists as all powerful agents of manipulation, etc.

France is not a perfect example. Fukushima demonstrated the kind of disaster that can happen despite best efforts and good operating records, and there is much debate in France about the risks of relying on nuclear going forward.[1]

[1] https://en.wikipedia.org/wiki/Nuclear_power_in_France

We shouldn't ignore waste or accident problems of course but it's always important to compare them to the alternatives. Given the problem of ocean accidification it's hard to see how replacing fossil fuel plants with nuclear isn't a net ocean environmental win. And replacing a coal power plant in china with a nuclear a nuclear plant you know is going to have a Fukushima meltdown in 30 years is still better for people and the environment. Or 10 "clean coal" power plants in the US with 10 nuclear plants of which 1 will melt down.

Of course, it's far better for health and the environment if we can replace them with solar and batteries. But perspective on the dangers of nuclear compared to fossil fuels is important.