[PaulHoule]

I don't believe it.

The problem with nuclear energy is not the availability or the cost of the fuel but the capital cost of the reactor and the high level of financial and operational risk involved with the construction. For instance there is an unlimited amount of handwringing over a closed fuel cycle costing a little more than an open fuel cycle but nobody points out that the capital cost of the reactor dwarfs fuel cycle costs for any fuel cycle -- no nukes hate reprocessing so they won't point this out and nukes don't want to remind you of the capital cost problem.

For every NPP that's had a nuclear meltdown there have been 20 that had a financial meltdown before they've even turned it on.

It drives me up the wall that big tech companies want to buy "a reactor" or an unspecified "SMR" but never an AP1000 (reactor that's actually been built) or even a BWRX300 (an SMR that might actually get built.) If there wasn't any bullshit a new build AP1000 would probably have a 10 year lag at least but...

... in the current international tariff situation it's almost impossible that any full-size or even moderate-sized reactor will be built in the US in the forseeable future because the US has no super-heavy press that can forge a nuclear reactor vessel. Japan, China, Korea, the UK, and many other countries have them and in the neoliberal world of a year ago we could have just had one made for us and shipped in by boat. The BWRX300 is the only western SMR that is far along and the pressure vessel will be made in Canada -- it's going to cost plenty no matter what but put 35% on top of that and you're doing the no nukes job for them. Way to go.

I want to see it work but I am not seeing realistic plans from the likes of Microsoft and Google, just the hot air from a 100W lightbulb when we really need 10,000,000 times as much heat!

[just_human]

> The problem with nuclear energy is not the availability or the cost of the fuel but the capital cost of the reactor and the high level of financial and operational risk involved with the construction.

Yes, in US and western Europe it's been practically impossible to build new reactors since the 90's for capex and regulatory reasons (both are related). However, we used to be able to build reactors significantly cheaper and faster and I'd argue we're on the path to do it again later this decade. There's no technical reason we can't solve this problem: there's bipartisan support for nuclear, willing financial backers, and no demand shortage. We're going to see 100+ gigawatts of new nuclear in the western world in the next 20 years.

[PaulHoule]

I want to see a real explanation of the bungling that makes projects go 3x late and over budget and it is not "environmentalists" who might make it go 20% late.

I've looked long and hard and not found an explanation of the bungling fitting the facts better than that it's like a poker game: the vendor never believed in the sticker price, but the vendors figured that once there were chips in the pot the sunk cost fallacy would mean the buyers would never fold.

Thing is, they do, at least in the U.S.

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

I think NuScale was trying to be honest about costs but the buyer in Utah built a process in which they could control costs by folding early and they did. Europe, China, and other places have more engineering thinking and less financialization and they're more likely to "stay the course" but as an engineer I'm not sure this is right -- it might work for China but not for Europe.

On one hand I'm glad to see GE get the BWR, especially the work done on ESBWR, back into the game with the BWRX300, but the costs they are quoting are too freaky low and their talk about "design to cost" makes it seem like they just quote the cost number that they need to be competitive with the solar sticker price without storage which will lure in the public as opposed to being competitive to whatever the (unknown) solar + storage sticker price will turn out to be. (e.g. highly variable because it depends by "how frequent blackouts will your accept?")

[just_human]

Lots of interesting history here, but most relevant was that regulatory and process changes starting in the 80's made it increasingly expensive to build reactors. As a result, reactor construction companies (notably Westinghouse) went bankrupt and no entity was willing to take financial risk to build new reactors. Western Europe is a different story, where political parties aggressively shutdown healthy nuclear plants and passed laws preventing new nuclear.

Much of this regulation and process overhead is now being rolled back in the US (by both political parties) and Europe is slowly coming around to allowing new nuclear. NuScale is one of many next gen companies (I hope they're all successful), but the traditional large reactors are also great and can be built cost effectively.

[PaulHoule]

I don't believe it -- although ideology makes explanations like that popular with a lot of people.

The cost escalations and bungling were well in progress before the TMI. The NRC streamlined the reactor approval processes in the 1980s by trying to separate the licensing of a standard reactor from the licensing of the site -- nobody took them up on the offer.

In the case of AP1000 builds both Sumner and Vogtle were held up for years because they were waiting for Chinese factories to figure out how to make parts, in some cases they never figured it out and they had to source them elsewhere. Factory modular construction was supposed to prevent bungling at the site but replaced it with bungling at the factory.

In theory the factories got up the learning curve and if somebody ordered another AP1000 it would be different, in practice the AP1000 is a Chinese reactor and the Chinese gave up on it for the Hualong One which there are (oddly enough) two designs for, which goes back to the designs the French were using back when they were building many plants on time and on budget... which is maybe a good thing, but they look pretty quick to move on to the Hualong Two and before they get up the learning curve on that one they'll be switching to the Three...

I'll agree that the Europe hired somebody who thinks like Amory Lovins to design the EPR and really did bungle the politics more than the engineering, but that's not the story in the US.

[vlovich123]

Regulatory requirements were definitely a real thing. One of the drivers was that nuclear companies were required by law to match the price of oil and any surplus profits from that had to be reinvested into safety and that set the bar for new safety requirements. What that meant was the 1970 oil crisis created a new level for nuclear safety beyond what was needed and that was locked in for future construction. The entire history of nuclear energy is one of bungled regulation and given the political power oil companies have had and continue to have, it’s not surprising given the existential threat nuclear posed.

[pfdietz]

> One of the drivers was that nuclear companies were required by law to match the price of oil and any surplus profits from that had to be reinvested into safety and that set the bar for new safety requirements.

This sounds like utter bullshit. Got references?

[nomel]

> Much of this regulation and process overhead is now being rolled back in the US

Bar graphs showing decreasing regulatory cost on page 6. Pretty dramatic recent change.

https://www.nei.org/CorporateSite/media/filefolder/resources...

[magicalhippo]

Here in Norway there's now talk about nuclear power, after a long time of little to no interest.

However they can't even put up wind turbines anymore, due to NIMBY issues, environmental concerns and whatnot. We had a ton of such projects but it's just about ground to a halt now.

And since our distribution network sucks, we've had a ~100x price difference between north and south for a long time now due to that, you can't just put it in the middle of nowhere.

As such I have very little faith they'll manage to put up a nuclear reactor in the near future, at least not close to initial cost and time. And none of that has to do with the details of building a nuclear reactor.

That said, there's change on the horizon. At least more and more people seem to be realizing that if they don't want wind turbines, they don't want huge swathes of solar panels and they don't want to alter more rivers then there's not a lot of options left on the table.

[XorNot]

It's just experience in most cases. We don't build enough so the management and project structures and experience to do it never get a chance to be efficient.

The right thing to do with something like the Vogtle plant for example would be to keep building them since you've just paid some very expensive costs learning what causes delays, but the knowledge of what gets the plant built - because it was built - is still there and fresh.

[PaulHoule]

That's why I wish we had more information about what happened to the AP1000 than has gotten out.

[johncolanduoni]

This is the idea behind the “small modular” part of SMR. Current nuclear projects are huge, largely bespoke efforts that require a bunch of contract firms working together on different parts of the project. The idea of SMR is to push most of the necessary parts one after another from a factory. The best analogy I’ve heard for this is comparing how the Japanese built planes in WWII (in small batches done by craftsmen) to how the US did (with an assembly line following a documented process). I buy the conceptual argument, but there are a lot of details to work out.

[ViewTrick1002]

We’ve been trying to build ”SMR”s since the 1950s and a bunch has been built throughout the decades.

https://spectrum.ieee.org/amp/the-forgotten-history-of-small...

The problem is also: who pays for the hundreds of prototypes before the ”process” has worked?

[johncolanduoni]

I guess the answer might be hyperscalers that want cheap electricity to run LLM inference. They’re already throwing tens of billions at AI, what’s a few billion more to have a chance at super cheap energy for their new data centers?

[bruce511]

Nuclear proponents argue that renewables (solar, wind) are not base-load, and nuclear is. They are correct.

But the people building power generation are doing it on a for-profit basis. Since solar is cheaper to deploy, faster to deploy, simpler to maintain and so on, that's what for-profit people build.

In other words, on the one hand you have large generators, requiring years of planning & permitting, a decade of construction, endless court battles from the anti-nuclear folks, generating returns 15 years from now, competing with the exact opposite (cheap, quick to build, beloved by eco folks, easy to run and maintain, off the shelf parts etc).

From a capital point of view its a no brainer. Capital follows profit, and solar is very profitable.

Nuclear may be good policy. Base Load may be very desirable. But unless govt is putting up the capital it just won't get funded. (Nuclear plants are being built, like in China, but using govt capital, which sees a return in more than just cash terms.)

There are lots of strong arguments for Nuclear. But Nuclear proponents need to address the capital requirements above all. Until the capital problem is solved, every other argument is useless.

[PaulHoule]

One radical answer that question which is often neglected for the facile "regulations" explanation is that we quit building coal burning power plants at the same time we quit building nuclear plants because the steam turbine and heat exchanger cost too much compared to natural gas plants.

If that's really the case then a Gen 4 reactor that runs at higher temperature, uses printed circuit or other advanced heat exchangers and a Brayton cycle gas turbine could win on the capital cost but it's easier said than done. There's not a lot of hope I think the LWR but the BWRX300 is at least trying to do it by deleting the heat exchanger and the only way you're going to get costs down radically will be by deleting things. Commercial Gen 4 reactors are at least 20 years out and we should have gotten started 20 years ago.

[philipkglass]

One radical answer that question which is often neglected for the facile "regulations" explanation is that we quit building coal burning power plants at the same time we quit building nuclear plants because the steam turbine and heat exchanger cost too much compared to natural gas plants.

The timing undermines this theory. The US added one nuclear reactor to the grid in 1996 then zero until 2016 (sort by first grid connection date here):

https://pris.iaea.org/PRIS/CountryStatistics/CountryDetails....

The US built an additional 58 coal generating units between 1995 and 2009 (see section "Age comparison of coal plants"):

https://www.gem.wiki/Existing_U.S._Coal_Plants

Combined cycle natural gas units were already cheaper to build in 1995, but the gradually rising natural gas prices over the next ~12 years meant that coal could still compete on cost for electricity generation. The cheap fuel for coal units counterbalanced the slower, more expensive construction process. It wasn't until fracked natural gas drove fuel prices down that coal unit construction ended in the US.

[jabl]

A lot of the natural gas plants are combined cycle, which includes a steam Rankine bottoming cycle.

[perihelions]

I don't see how this isn't dispositive on the economics question. That markets (overwhelmingly) choose to build combined-cycle natural gas plants, choose to add the Rankine bottoming cycle, means the marginal cost of the steam turbine is *less* than the marginal cost of the fuel saved by the efficiency gain. That's the case even in the USA; and natural gas elsewhere in the industrial world is integer-multiples more expensive.

The natural gas plants without steam turbines are precisely the load-following plants that run for a fraction of the time (or at a fraction of their capacity); the relative weight of capital vs. fuel costs is inverted. (Or those, like xAI in Memphis, which are rapidly assembled in rushed desperation. I wonder if that will be a trend in the datacenter boom: designs limited, not by costs under normal market conditions, but bottlenecks affecting rushed projects. Nuclear SMR's would seem to be worst at this—the designs they expect to use haven't even been built yet!)

[PaulHoule]

Yes, and the bottoming steam turbine is 1/3 the size of a steam turbine rated for the full power output so… radical capital cost reduction.

It isn’t just the turbine but the heat exchangers, in a PWR the ‘steam generators’ are water-water heat exchangers that are usually larger in volume than the reactor vessel. Many LMFBRs had two stages of heat exchangers (sodium-sodium and sodium-water) even larger heat on the water though SuperPhenix has relatively affordable secondary heat exchangers and never had them catch on fire.

[jabl]

> Yes, and the bottoming steam turbine is 1/3 the size of a steam turbine rated for the full power output so… radical capital cost reduction.

It's a cost reduction, but likely not radical when talking about a nuclear power plant. For a cost breakdown of a nuclear plant see

https://world-nuclear.org/information-library/economic-aspec...

So the "conventional island", which would include the steam turbines, condensers, generators etc. is about 15% of the cost. Reduce that to a 1/3 the size, and cost drops to 5% of the total, a savings of 10%. Probably even not that much, since a steam turbine 1/3 the size probably costs more than 1/3 the cost of a "1/1" size turbine. And then the remaining 2/3 of the power output would have to be generated some other way, so would shift cost somewhere else. Of course, some part of the cost of the nuclear island can be attributed to steam production as well. In any case, all in all I don't see this as making or breaking the economics of a nuclear plant. The issues that cause nuclear plant costs to skyrocket lie elsewhere (and no, just blaming regulations is overly simplifying it as well, though a popular scapegoat).

(I'm not sure, but I suspect what's making coal non-competitive with gas isn't so much the steam turbines, but rather that there's more labor and machinery involved in burning coal than gas, from mining, transportation, pulverizers, and then all kinds of exhaust gas treatment used at least in the civilized world, ash handling etc.)

> It isn’t just the turbine but the heat exchangers, in a PWR the ‘steam generators’ are water-water heat exchangers that are usually larger in volume than the reactor vessel.

Yes, that's true. The BWRX300, which of the current crop of SMR's is probably the one with the most realistic prospects of actually being built somewhere, is a BWR, and the maker claims one reason for the supposedly good economics is that they have spent a lot of effort on minimizing construction cost and equipment needed. We'll see, I guess. I think historically the economics of BWR's vs PWR's is mostly a wash.

> Many LMFBRs had two stages of heat exchangers (sodium-sodium and sodium-water) even larger heat on the water though SuperPhenix has relatively affordable secondary heat exchangers and never had them catch on fire.

The follow-up ASTRID project, which never left the drawing board, used a sodium-air (or might have been nitrogen, to avoid issues with trace contaminants in air since it was all closed cycle anyway?) heat exchanger and Brayton cycle turbomachinery, to avoid any potential issues with sodium and water. I think it was supposed to have slightly lower thermal efficiency than an equivalent steam plant, but maybe somewhat lower capital cost.

[credit_guy]

When a big tech wants to build some huge datacenters, where they plan to put hundreds of thousands of ultra-expensive GPUs, they want to run those GPUs as close to 100% of the time as possible. Every hour the GPUs don't run costs them money. From the point of view of Microsoft, having an SMR next to a datacenter makes perfect sense. Solar and wind can do the job, if coupled with batteries and/or natural gas. But than you need a grid operator. If all you need is electricity for a datacenter, and you don't care about being connected to the rest of the grid, then you want as simple a solution as possible. And an SMR promises to be just that, a turn-key solution to get continuous and constant electricity.

[bruce511]

I think "promises" is the key word there. Data centre's want power, as you say, but they want it now, not 15 years from now.

So yes, when SMR's are "off the shelf" (aka from "order" to producing) , including permitting, construction etc, within a couple years then they are appealing.

I don't think we're quite there yet.

[credit_guy]

Sure. But this is why what Microsoft did here was just a hedge. It did not cost them much (if anything at all) to become a member of the World Nuclear Association. If the SMRs become reality a few years down the road, and if the demand for datacenters increases significantly because of the increased use of LLMs, then they stand to benefit a lot. If either of this does not pan out, then what's the risk for Microsoft?

[johncolanduoni]

The point of the baseload argument isn’t the “desirability” of power sources that can provide baseload, it’s the necessity. Renewables that can be scaled up (i.e. not niche cases like geothermal) are all too inconsistent to replace the entirety of generation without storage. Other tactics like long range transmission can reduce the amount of storage needed but not eliminate it. Fully replacing generation with renewables isn’t just unprofitable without storage, it’s impossible.

Storage is making great strides but for it to get good enough to fully convert the grid we need qualitative advances in the underlying technology, not just manufacturing scale driving down prices.

[pfdietz]

There is necessity with baseload plants: they have to be run at high capacity factor or else their economics go all to hell. This is especially true of nuclear where capex dominates. So describing something as "baseload" is actually describing a defect: it's a generation technology that cannot be practically dispatched.

[johncolanduoni]

It’s only a defect if you try to make the grid 100% nuclear, just like solar’s variation is only a defect if you try to go 100% solar. It’s not a competition where either is likely to “win”, they’re just two different tools for power generation.

[bryanlarsen]

It wouldn't be a defect if it was complementary to solar. But it's the same defect as solar/wind, so it is a defect.

[johncolanduoni]

How is it the same defect? Nuclear plants can run all the time and have to if they have any hope of recouping investment. Solar can’t run all the time but is super cheap so it doesn’t have to. You still need responsive capacity but even if you keep natural gas around for that you’ve made a massive dent in fossil fuel usage - bigger than solar or nuclear could do without the other.

[bruce511]

Of course electricity at night is highly desirable. But there are no economic incentives to build it.

From a purely financial point of view, base load is not appealing. Whereas cheap solar is appealing. If I have a billion$ to invest, I know which one I'm choosing. I'm maximizing return, not "societal good". Which is why govt is best placed to build base load, since they optimize for societal good, not profit.

To make base load appealing to investors we need expensive power at night. But that's countered by local battery storage.

To be clear, this is not a "what we need" argument. It's a capital argument. Private Power suppliers chase profit, and there's more profit in daytime power than nighttime power.

[johncolanduoni]

> Of course electricity at night is highly desirable. But there are no economic incentives to build it.

Wait, what? Who is going to accept having no power at night at their house? Ignoring the fact that the intra-utility trade does provide a direct economic incentive, nobody is going to live somewhere the power companies can’t keep the lights on 24 hours a day most days (in the developed world anyway).

[bruce511]

You're looking at this from the consumer point of view. But consumers provide income, not capital.

Consumers may, or may not, have a choice of power providers. They can choose to "accept" what is on offer, or remove themselves from the grid. But they have very little negotiating power.

Actually it's pretty easy for (residential and office consumers to spend their own capital on batteries and inverters. Most homes consume (or can be set to consume) reasonably low power at night. A 20 kw/h battery will cover most homes easily.

(Solar panels aren't necessary for this.)

The capital cost, and savings therefrom, put a hard limit on what suppliers can charge for night time power. And of course storage is just as attractive to suppliers. (More capital-attractive than say a nuclear plant.)

As consumers we are used to simply announcing our needs. And assuming companies will expend any capital necessary to meet those needs. In practice it doesn't work that way, as rural phone/internet/cable consumers will testify.

Once you see electricity generation as a capital issue, not a consumer issue, things get clearer.

[ZeroGravitas]

The point of separating electricity artificially into "baseload" and "peaking" was the quirk of engineering that made coal and nuclear cheaper if you ran them flat out.

In a world where both solar and wind are massively cheaper, that entire paradigm collapsed. Even more so when you can reuse the same hydro and gas that was working as peaking as "firming" to complement the new model.

[nomel]

Here's a nice pie chart of the costs:

https://ifp.org/nuclear-power-plant-construction-costs/

[ksec]

> BWRX300

I believe Rolls Royce is pretty close as well. But both have yet to deploy a single working example. And it doesn't seem we are anywhere close to see one yet.