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There's no measure by which nuclear energy is the "energy of the future". It's too complex, too expensive and it doesn't scale. SMRs are proving to be a fever dream with ever rising costs and the number of nuclear reactors in operation is decreasing year by year and both Wind and PV are now each producing more electricity than nuclear.

Nuclear has had its moment. That moment is gone.

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PWRs are not really that complicated. They are just very hot metal rods inside a thick steel pressure vessel that boil water to make steam.

"Nuclear has had its moment. That moment is gone."

When CO2 caused climate changed is posed to be civilization altering this is a very very foolish thing to say.

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Nuclear energy is still turning water to steam, no really future like.

Turning sun light to electricity on the other hand is more that

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Every SMR startup is failing. The more they progress, the more they revise their costs upwards.

SMR make as much sense as space datacenters. You can gaslight investors, you can gaslight HN, you can gaslight a national parliament full of lobbyists, but you can't gaslight thermodynamics.

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> Every SMR startup is failing.

https://news.ycombinator.com/item?id=48586648

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Have you read the comments?
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>SMR make as much sense as space datacenters.

you are in this thread a lot, so i am guessing you must be very familiar with the industry. maybe you can help me understand:

is the wikipedia on SMRs incorrect/lying when they say that there are commercially operating SMRs since 2020?

and how have so many smart people and companies been duped into seriously considering SMR technology if SMRs apparently break the laws of thermodynamics?

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>commercially operating

And struggling, propped up by taylor-made laws and public money.

>how have so many smart people and companies been duped into seriously considering SMR technology if SMRs apparently break the laws of thermodynamics?

Never said they break the laws of thermodynamics. They are just inefficient and will never be more efficient than alternatives such as... Bigger nuclear reactors.

Or solar.

And how long have you been out there? Have you never seen investors dumping and wasting billions in dead-ends? Never seen a mania before?

Nuclear attracts clever people, but it isn't smart nor wise.

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Efficiency is not the problem. We have plenty of nuclear fuel.
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I think you have a misunderstanding of what a SMR is supposed to be.

Nuclear power plants are eye watering levels of expensive. The require massive scale and cost with lengthy approvals and requirements, the fundamental idea of SMRs is to move that cost and approvals into a smaller scale so that multiple standard units can be produced and deployed in a turnkey situation, they still will be expensive but the time to deploy and cost will be significantly reduced.

We also know SMRs work very well, considering the majority of the US Navy is powered entirely with SMRs and have been for a very long time. Off the top of my head ship power has been exported to local areas for disaster relief

Solar is absolutely fantastic and your average person should not be hawking at solar for your home to offset your power bill. The problem with solar is that you need power 24/7 and solar will not make power in the night.

I don't think the likes of Westinghouse, Siemens, Rolls Royce and GE are duped. They are trying to solve a very hard problem!

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>The problem with solar is that you need power 24/7 and solar will not make power in the night.

Ok, question: for the cost of one nuclear power plant, how many batteries can you have?

For the cost of the R&D of one next generation nuclear reactor design, how many next generation battery and solar panels technologies can you develop?

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This is such a silly argument. Battery and solar technologies are progressing regardless of people building nuclear. It's simply not the case that we can stop investing in nuclear and use that money to accelerate battery/solar.

The best energy strategies are all-of-the-above.

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> For the cost of the R&D of one next generation nuclear reactor design, how many next generation battery and solar panels technologies can you develop

This is a horrible argument. Yeah, let’s not spend money improving technology. We wouldn’t have increased Solar panel efficiency if we followed such ill advice.

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>'taylor-made' Says it all, doesn't it
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>Never said they break the laws of thermodynamics.

true, you said "gaslight thermodynamics", which i have no idea what that means, so i took a guess at what you were implying.

>never be more efficient than alternatives such as... Bigger nuclear reactors.

is efficiency really the only metric to be considered? i feel like available space, availability of alternatives, time to complete construction, etc. are worthwhile to consider.

>And how long have you been out there? Have you never seen investors dumping and wasting billions in dead-ends? Never seen a mania before?

considering the length of time and sheer number of people, companies, and governments worldwide considering/investing in SMR tech it seems unlikely to be a mania. but i am not an expert. you are talking like you are one, which is why i am asking questions.

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>i feel like available space, time to complete construction

All of these favor again bigger reactors.

>considering the length of time and sheer number of people, companies, and governments considering/investing in SMR tech it seems unlikely to be a mania.

All of the Swiss energy companies are asking to be bailed out in advance of the investment in nuclear.

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Sweden recently did the same: in order for companies to agree to make new reactors, the government had to promise them a price floor for the electricity they produce. The price floor suggested is more than twice the current price on the spot market. That means that, for the lifetime of those reactors, Swedish taxpayers will be subsidizing production of nuclear power. I thought the idea was that they would be profitable? What happened to the political right’s love of the free market? When politicians go fixing prices with this kind of ”advance bailout”, it just makes it look like they are trying to get a nice retirement job in the nuclear power sector…
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Base load generation.

Yes, we have hydro.

Wind is way too unpredictable, solar is too.

So, we can only have 2 powers to provide base load in Sweden.

https://www.svk.se/om-kraftsystemet/kontrollrummet/

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>All of these favor again bigger reactors.

how does having less available space favor a bigger reactor?

and how is constructing a bigger reactor faster than constructing a smaller one?

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There are two ways of achieving economies of scale: making things bigger or making more of them.

For small quantities, the former is usually more effective -- making things bigger lets you make fewer of them, reducing costs.

For large quantities, a factory can enable insane economies of scale.

SMR proponents are talking about building dozens of reactors. That fits very firmly in the "small quantity" column where economies of scale almost always favor building things bigger.

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If you need 500 MW, you build one 500 MW reactor, not five 100 MW reactors. They will take more space.

As for speed, a 100 MW reactor is not commissioned in 1/5 of the time a 500 MW reactor is.

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I think the promise of SMR is that the 1/5th reactor can be built in 1/2 the time. And you build five of them in parallell. And you have your power sources gradually online over about the same time as one ”big bang” build would take.

I don’t think it’s going to work out that way, but that’s how it’s being sold.

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Even like that, it is not clear-cut. 1/5 in 1/2 the time is still 2.5 shorter per worker, and building in parallel require multiplying expert builders, which is not easy (as it takes time to acquire the expertise and you don't want to learn a trade to build one project and have nothing to do next).

But, yes, I get it is how it is sold. Just that even sold like that, people with common sense should say "wait a minute, that's obviously not that simple".

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Just a guess (I'm not the previous user), but I guess you need to look at the space _per GWh_?

If a big nuclear reactor takes 10x more space but has 20x more capacity, then it means not having much space favors the big nuclear reactor rather than building 10 small ones that will take twice more space.

(and same for the time)

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its probably my fault for not making myself clear. i mean when the available space is constrained to a specific amount of space that cannot be exceeded.

just picking random numbers:

i have 1 square mile available. a big reactor takes 4 square miles. i cannot fit a big reactor, despite the bigger reactor being more efficient.

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well, I don't think that there is a real problem of "1 square mile is available but not 4 square miles" (this is a different sentence than "there is not enough space"). Especially as small reactor also need to be placed very specifically. So even then, it is still possible that the advantage is for big nuclear plant, as they are still more compact per GWh.
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>"1 square mile is available but not 4 square miles" (this is a different sentence than "there is not enough space").

how are these different? one is an example, one is general, but they communicate the exact same point. if you have something that requires 4 sq. miles, you cannot fit it into a place that is 1 sq. mile in size because there is not enough space to fit it.

>as they are still more compact per GWh.

i am really struggling here... if i cannot fit something large, whether the large thing is "more compact per GWh" does not matter. i only have so much physical space to work with. if its too big, its too big.

for a more easily visualized example, you cannot fit a reactor from three mile island into a submarine. efficiency doesnt come into the equation, because physical space constraints get in the way first.

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What are the challenges they face?
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One is regulatory. At least in the US, every nuclear reactor that produces at least 100 MW needs to carry a 375 million dollar insurance policy at minimum. Under 100 MW there is an alternate schedule that ranges from 5 million to 75 million scaling based on output. But the net result is that it's still more profitable to built a single large reactor, since a 1 GW reactor is less to insure than 10 100 MW reactors. This is written into law, it would require Congress to change it.

Second is that nuclear reactor efficiency tends to improve with size. The ratio of thermal watts to electric watts tends to be better with large reactors. I'm not super well versed on the engineering tradeoffs here by my rough understanding is that waste heat scales with surface area while useful energy extraction scales with volume.

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In the grand scheme of things, that doesn't seem to be too expensive. According to the NRC, insurance is per site, and additional reactors on a site don't increase the insurance nearly as much as the first. The example they give is $1.1 million annual premium for a $500 million policy, with multi-reactor sites going up to $1.5 million. They also mention property insurance ($1.06 billion policy) and they didn't discuss the premiums on that, but as it's not liability insurance it's probably cheaper.

The big costs are still going to be the cost of siting and building the reactor, the fuel, and the ongoing cost of running it. They pay off over a very long time horizon, so it's also the opportunity cost.

https://www.nrc.gov/reading-rm/doc-collections/fact-sheets/n...

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Doesn’t China have SMRs?
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Just one so far and it's not particularly small compared to a more conventional reactor.

Russia actually does have a smallish SMR but it wasn't terribly cheap to build nor operate. IIRC it is in the form of a ship and used to power a city somewhere in the north.

SMR has a place for sure but no one has demonstrated the unit costs savings of making a lot of them yet.

You can actually get some, if not most, of the economy of scale by doing a fleet build of one specific design. The US seems to be working on that and picked the Westinghouse AP-1000. I think that initiative has a decent chance of succeeding. The first few will be slow and expensive to build (even China has had delays with their nuclear roll out) but the subsequent ones will get cheaper and faster to build. This is how some countries did it during the first nuclear power expansion era.

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How are SMR's "gaslighting themodynamics"? I mean, sure, I can accept that they're not economical with current tech, but it's not a frigging' perpetuum mobile, it's feasible technology.
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Thermodynamics are the reason why SMR aren't, and will never, be economical. A bigger nuclear reactor will always undercut your price per watt.
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> Thermodynamics are the reason why SMR aren't, and will never, be economical.

And the link between thermodynamics and the price of electricity is what?

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Your small nuclear reactor is going to need almost as much engineering , plumbing, safety mechanism, personnel, maintenance, etc... as your big nuclear reactor.
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Not if it's mass produced
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Let's distribute the risk everywhere, what could go wrong?
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The value propositions of SMRs are logistics and re-use of existing infrastructure. The idea is that you could have easily transportable reactors that you can plop down in an existing coal plant, and then reuse the turbine, dynamo, etc. that are already in place.

The fact that we haven't seen more widespread use of SMRs suggests that you're right. But it's important to point out that there are cost saving opportunities that could potentially reduce the net price per watt despite worse thermodynamic efficiency.

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The mindset that makes people stuck in time. Sorry but SMRs are potentially very cheap. Not at this point. ,but when operated on scale they will be. You need to start
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"SMR make as much sense as space datacenters."

So a whole lot of sense given the entire US Navy uses them and I already have one datacenter operating up in space (small test unit that over 3 months has provided ZERO issues) and a bigger one heading up into orbit next year when it's done being made.

"but you can't gaslight thermodynamics"

No but you can certainly conflate them like you're doing right now.

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The Navy uses highly enriched uranium for its reactors, something like 70-80% enrichment. This is a non starter for civilian use, on account of proliferation concerns. That, and the enrichment requirements drive up fuel costs.
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Naval reactors use HEU specifically so that humans can live and work in close proximity for long periods of time.

Land-based deployments don't have this constraint.

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>the entire US Navy uses them

Is the business of the US Navy to sell electrity on the market?

You are the one conflating things that have absolutely no connections.

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Yes, SMRs probably have a small niche market on military-adjacent applications.
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Ok, this is interesting. I am skeptic about DC's in space, but I do appreciate people actually doing stuff. What is it computing up there. How did you get it up? How does one usually talk with their satellite. I guess you don't merely have a dish since it's probably not geostationary.
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