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hwillisyesterday at 1:23 PM7 repliesview on HN

And a contrasting article from IEEE: https://spectrum.ieee.org/the-forgotten-history-of-small-nuc...

> Samuel B. Morris, the general manager and chief engineer of Los Angeles’s Department of Water and Power, traveled all the way to Geneva in 1955 to attend the first International Conference on the Peaceful Uses of Atomic Energy. There, he made a case for small reactors, arguing that because the “number of small units…is many times the number of large units,” there could be “economy in development and repetitive manufacture” of the small units.

> But nothing in the history of small nuclear reactors suggests that they would be more economical than full-size ones. In fact, the record is pretty clear: Without exception, small reactors cost too much for the little electricity they produced, the result of both their low output and their poor performance.

For me, SMRs don't pass the smell test. Buying one big plot of land for a reactor, building one power interconnect, having a localized water impact is way easier and cheaper than many. Even if its cheaper to build small reactor vessels, MANY of the other costs become more expensive in larger numbers. Costs that you can ignore while you're just building a prototype.

If it's so much cheaper to build multiple small reactors, just build one big plant with 24 small reactors. Thing is the nuclear reactor part is only 10-15% of the plants full cost: https://world-nuclear.org/information-library/economic-aspec...


Replies

mayamayesterday at 2:15 PM

> Even if its cheaper to build small reactor vessels, MANY of the other costs become more expensive in larger numbers.

There is no way SMR could beat solar+battery power cost even now. With sodium and other batteries projected to reduce storage cost, it is even more unlikely that SMR could be price competitive in future grids. SMR is the only way that dying western nuclear industry could attempt to deal with ballooning compliance and finance costs and hope for revival. China or India doesn't have this compliance cost and still build conventional nuclear.

Even for the SMR usecase that got funding recently, mega datacenter electricity, there is new geothermal power companies getting funding and are transitioning from pilot projects to production. Some are using tech that is already being used in oil fracking industry for decades, so new geothermal tech scaling up has far less roadblocks technology and compliance wise. So other than military and mobile civil applications like nuclear icebreaker, I don't see the chance of SMR succeeding anywhere else.

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arpinumyesterday at 1:49 PM

SMR is driven by funding, insurance, and regulation. China doesn't have these issues and builds conventional at a great price. China is building 37 reactors, only 4-5 are SMR-type units, and are larger at 600MW. The rest are standard PWR, and the 40+ in planning are dominating by standard PWR.

Regulatory risk is too high, building too infrequent to understand costs, funding for first-of-its-kind is too hard for nuclear in most countries. SMR makes it fundable. New designs give the hope that regulatory burdens can be lowered.

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briffleyesterday at 2:33 PM

> 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. Standard reactor, standard monitoring systems, standard control room able to monitor multiple reactors, etc.

Plus, when you have 12 of them onsite in one large area, you can take one offline for refueling, and still produce power with the rest of them.

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nradovyesterday at 7:40 PM

Security costs are also an obstacle. Any nuclear reactor requires 24×7 armed security and that's largely a fixed cost regardless of power output. You need almost as many guards for a small reactor as a large one.

throw0101dyesterday at 4:43 PM

> For me, SMRs don't pass the smell test. Buying one big plot of land for a reactor, building one power interconnect, having a localized water impact is way easier and cheaper than many.

Some things would depend on the specific location and the grid around it:

The Point Lepreau Nuclear Generating Station in New Brunswick may be 'overkill' because when it goes down every few years for inspections/retooling, there's little other redundancy available. SMRs would be useful for that regional grid: install 3-4 and one can go down with less fuss.

In (e.g.) Poland there were small/medium coal-fired generation stations near coal mines. If the mines are now empty (or retired for climate change), then the grid connections could be reused for SMRs on an existing generation site: less need to find a new site and build new power pylons, etc.

gwbas1cyesterday at 6:57 PM

There's a political issue. Just look at how hard it's been to protest all the new gas plants that came up over the last ~20 years. The reason is that we built many small gas plants, instead of a handful of large ones. It divided up the protesters to the point where they couldn't work together.

When we built less, but larger, nuclear power plants, they're easier to protest. If we can make SMRs economical, it makes it significantly harder to protest.

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tastyfreezeyesterday at 1:52 PM

SMR proposals still use one plot of land. The plant is just built to house multiple reactors.