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Smaller reactors bring nuclear power closer to fulfilling its promise

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Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#231

Post by HappMacDonald »

idiotsecant wrote: post #188
ViewTrick1002 wrote: post #125

Earlier quoted context omitted.

Please, don’t cite the LFSCOE paper again. Citing it shows you have a beef against renewables. That paper uses one renewable source, like only solar, and 2018-19 cost data for storage. A real grid is made up of a mix of sources, which is why the research lately has focused on system costs. All those analyses find that renewable grids are far cheaper than if involving new built nuclear power. Here are two modern paper…

A) I am an electrical engineer who makes a living designing control systems for renewable generation. I know more about most of this than just about anyone in this conversation. B) the post I am replying to is specifically calling for a 98% solar grid.

You replied to: "The most cost efficient new-build grid is 90-98% solar/wind/battery depending on your locales insolation & wind coverage. (Source Ember Energy)"

https://news.ycombinator.com/item?id=49477559#49481711

There's a big difference between "letting the facts guide the path" and tilting at strawmen built out of straw nobody else even brought into the discussion.

If you'd like to make the point that "cost of panels" can be misleading when supporting components and interconnects begin to take up the lion's share of costs then that sounds like a noble thing to remind folk of, but ideally not as a segway into shilling more fracking which includes untold environmental costs as externalities.

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#232

Post by reformdEngineer »

pfdietz wrote: post #59
briffle wrote: post #58

Earlier quoted context omitted.

> If it's so much cheaper to build multiple small reactors, just build one big plant with 24 small reactors. That is literally the plan with several designs like NuScale (and I think TerraPower). The plan with NuScale is to ship the reactors on rail or barge, and then truck it in the last few miles. So they cost savings is in not having to custom desgin the actual components for each site, and build them on site. Sta…

NuScale infamously failed to get their reactor funded in Utah (UAMPS and the CFPP), it was just too expensive. Costs kept rising, large utilities declined to sign up, and in the end those utilities remaining were going to hit the contractual off ramp so it was just cancelled. I have some links to minutes of municipal utility meetings in Idaho Falls that showed the wheels coming off (even though there was great local…

Can you share the links? Would be interested to see! Thank you in advance

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#233

Post by ViewTrick1002 »

chickenbig wrote: post #230
ViewTrick1002 wrote: post #121

Earlier quoted context omitted.

Not sure what relevancy a 2019 paper has today? It also seems like they are constraining the system to have no overproduction. It’s like assuming that a fossil based system has all its producers generating the expected capacity factor and then smoothing out the season and daily demand changes with storage. Due to the difference between summer and winter demand such a fossil system would also need to have months of st…

> Not sure what relevancy a 2019 paper has today? The underlying demand and production has not changed so much since then. The requirements for storage still exist, and strongly depend on when the power is delivered as well as needed. > a fossil system would also need to have months of storage Coal and gas also get produced in the winter at a relatively constant rate. Plus we know how to handle piles of coal, caverns…

We have vastly moved the scientific frontier of modeling our energy systems since 2019.

All those analyses find that renewable grids are far cheaper than if involving new built nuclear power.

Here are two modern papers on the subject:

https://www.csiro.au/-/media/Energy/GenCost-2025-26-Final/Ge...

https://www.sciencedirect.com/science/article/pii/S036054422...

I find it telling that you call it an ”economic problem” and ”intermittents”. It seems like you have an axe to grind, but not much backing your standpoint anymore. So you’ve fallen to using derogatory.

Those same fossil fuels have the same economic ”crowding” out problem when cheaper sources in the same class delivers.

A single cycle gas turbine would love to get paid running at 100% all year around. It doesn’t because CCGT plants with higher efficiency undercut it.

Just like what happens in renewables. They start crowding out each other. Storage steps in and solves the peaks. More renewables come online until they ”crowd each other out” and around we go.

That’s called being a market. Which you nuke fans seems deathly afraid of given the economics of new built nuclear power.

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#234

Post by hvb2 »

agarwaen163 wrote: post #143
hvb2 wrote: post #2

> but SMRs should be cheaper and easier to construct. The word should is doing some real heavy lifting there. Especially given the subject. I guess we'll know in 2030 when one should come online.

Except Valar already did it earlier this year.

Not sure what you're referring to but in June they achieved criticality in a demo. While a good milestone that's not at all a functioning reactor connected to the grid. Let alone anything like a repeatable consistent production of said reactor.

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#235

Post by chickenbig »

ViewTrick1002 wrote: post #233
chickenbig wrote: post #230

Earlier quoted context omitted.

> Not sure what relevancy a 2019 paper has today? The underlying demand and production has not changed so much since then. The requirements for storage still exist, and strongly depend on when the power is delivered as well as needed. > a fossil system would also need to have months of storage Coal and gas also get produced in the winter at a relatively constant rate. Plus we know how to handle piles of coal, caverns…

We have vastly moved the scientific frontier of modeling our energy systems since 2019. All those analyses find that renewable grids are far cheaper than if involving new built nuclear power. Here are two modern papers on the subject: https://www.csiro.au/-/media/Energy/GenCost-2025-26-Final/Ge... https://www.sciencedirect.com/science/article/pii/S036054422... I find it telling that you call it an ”economic problem”…

> https://www.csiro.au/-/media/Energy/GenCost-2025-26-Final/Ge...

It is interesting to see how large-scale nuclear is handled.

120% and 60% increase in cost for FOAK and NOAK (Table 2-1), plus no learning rate for nuclear construction beyond that (Table C.2).

Interest rates during construction unfairly penalise nuclear as "GenCost uses the simplest way which is to increase the capital cost by the assumed discount rate raised to the power of the construction time" (page 97)." This results in ~20% increase in capital costs against other simple scenarios like equal construction costs across each year.

30 year plant lifetime, rather than say 60 years. That results in ~10% increase in capital costs.

> Those same fossil fuels have the same economic ”crowding” out problem when cheaper sources in the same class delivers.

That line of reasoning only works if there is something to make one plant more expensive to produce electricity than another. For natural gas the cost of fuel is far greater than the CAPEX. For intermittents only the variable OPEX can distinguish between generators, which is mostly for wind and I guess most severely for offshore wind. Cannibalisation is the big problem for intermittents. The notion of succession doesn't work for them.

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#236

Post by dalyons »

UltraSane wrote: post #223
dalyons wrote: post #218

Earlier quoted context omitted.

thats, not true at all. Safety costs a little, but they are fundamentally massively complicated, huge, specialized, EXPENSIVE things to build. They require 100s of staff to run at all times. The insurance is so expensive only nation states can back them. The economics are flawed because on modern grids with cheap renewables, they will never pay back the ridiculous up front capex. Relaxing regulations changes very lit…

You can't compare wind and solar to nuclear you have to compare wind and solar with enormous amounte of battery storage which is extremely expensive and it would be hard to make enough storage

You just keep moving the goalposts and not responding to arguments. Until you have some idea of how nuclear is ever going to be cost competitive on today’s grids, good day to you.

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#237

Post by [deleted] »

UltraSane wrote: post #224
dalyons wrote: post #89

Earlier quoted context omitted.

it is not at all a perfect match for nuclear. Solar produces incredibly cheap power for the daytime hours, pushing the nuclear off the grid (why would a data center buy expensive nuke power in the hours when cheap renewables are available?). Nuclear needs to be running and selling power at its high price 24/7 for it to be even close to economically viable. Only supplying power that people want(due to its high price)…

Data centers need power at night

[deleted]

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#238

Post by dalyons »

UltraSane wrote: post #224
dalyons wrote: post #89

Earlier quoted context omitted.

it is not at all a perfect match for nuclear. Solar produces incredibly cheap power for the daytime hours, pushing the nuclear off the grid (why would a data center buy expensive nuke power in the hours when cheap renewables are available?). Nuclear needs to be running and selling power at its high price 24/7 for it to be even close to economically viable. Only supplying power that people want(due to its high price)…

Data centers need power at night

How about you try to explain how this changes the economics of nuclear, and I’ll wait.

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#239

Post by pfdietz »

reformdEngineer wrote: post #232
pfdietz wrote: post #59

Earlier quoted context omitted.

NuScale infamously failed to get their reactor funded in Utah (UAMPS and the CFPP), it was just too expensive. Costs kept rising, large utilities declined to sign up, and in the end those utilities remaining were going to hit the contractual off ramp so it was just cancelled. I have some links to minutes of municipal utility meetings in Idaho Falls that showed the wheels coming off (even though there was great local…

Can you share the links? Would be interested to see! Thank you in advance

Here's one of the meatier ones (Feb. 2023).

https://idahofallsidaho.gov/AgendaCenter/ViewFile/Minutes/_0...

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#240

Post by pfdietz »

agarwaen163 wrote: post #147
pfdietz wrote: post #59

Earlier quoted context omitted.

NuScale infamously failed to get their reactor funded in Utah (UAMPS and the CFPP), it was just too expensive. Costs kept rising, large utilities declined to sign up, and in the end those utilities remaining were going to hit the contractual off ramp so it was just cancelled. I have some links to minutes of municipal utility meetings in Idaho Falls that showed the wheels coming off (even though there was great local…

Your last point is entirely backwards and missed the scaling concept entirely. I suggest you watch a documentary on the Model T. The point being that these aren't civil projects once it's modular. The prices and material are what's being optimized. To compare to large RPVs and BWRs efficiency is idiotic as that's the only place they beat SMRs and the known downside to SMRs which is the point of scaling it. It has alw…

> The point being that these aren't civil projects once it's modular.

But that's simply wrong. All the projects (except for silly microreactors which don't have a prayer of being competitive) involve substantial civil engineering.

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