[wongarsu]

As long as the gas plants aren't burning any natural gas, I would say that's fair.

Standing by to supplement power on load spikes is one of the primary roles of gas plants (together with pumped hydro), and that they didn't need to supply any electricity over those six days is noteworthy.

From a climate standpoint there also isn't much wrong with having generating capacity in fossil fuels, what matters is how many greenhouse gases and how much pollution they put out. Which isn't much if they are just standing by.

[gustavus]

Of course if they had a nuclear base they wouldn't even need the natural gas plants.

[adrianN]

No? Either you have enough nuclear to cover 100% of peak demand, in which case you just run them exclusively (at a terrible capacity factor) because nuclear is almost exclusively capex, or you don't, in which case you need gas peakers.

[ajross]

Nuclear is emphatically not an instant-on hot backup. Plants take time to spool up, and very importantly time to cool down. Fukushima happened because you can't just turn a reactor off, it produces energy that has to go somewhere while the intermediate fission products decay over hours-to-days.

[troupo]

> Nuclear is emphatically not an instant-on hot backup. Plants take time to spool up, and very importantly time to cool down

All modern nuclear plants work in load following mode with ability to change ant the rate of 3-5% of their rated capacity per minute.

Graph and text on page 8: https://www.oecd-nea.org/upload/docs/application/pdf/2021-12...

> Fukushima happened because you can't just turn a reactor off,

Fukushima happened because the plant was hit with both an earthquake and a flood significantly exceeding its operational parameters (already extremely high)

[ajross]

> Fukushima happened because the plant was hit with both an earthquake and a flood significantly exceeding its operational parameters (already extremely high)

That's exactly the incorrect analysis that caused the meltdown!

That use of "and" and "both" is simply wrong. It wasn't an unforseeable collision of two events, it was a single event (an earthquake) with a predictable correlate (a tsunami). It's not like people didn't know that tsunamis follow earthquakes, and no one who does know that would make the argument you just did.

[troupo]

https://news.ycombinator.com/item?id=38304582

[VaxWithSex]

Nobody seems to get that these operational parameters were set and approved and told to be save and then they were still exceeded, lol.

[troupo]

This was literally the definition of a black swan event: "an event that comes as a surprise, has a major effect, and is often inappropriately rationalized after the fact with the benefit of hindsight"

[hef19898]

No, Japanese authorities and TEPCo knew tgat earthquakes and tsunamis could happen, and usually together. They planned for it, they simply planned insufficiently, so quite the opposite of a black swan.

[hef19898]

There is basically nothing correct in your statement.

[avar]

In this scenario you could just run the nuclear plant all the time, but just direct its electric production to heating a giant pool of water or whatever.

Then when the grid needs more power you do less of that, and instead send electricity to the grid.

[ajross]

Yes, but the point is that the problem is isomorphic to wind or solar: you get power when you don't want it. So nuclear isn't backstopping any particular need, it has the same drawbacks. The reason gas plants are used as peaker plants is that they can be turned on and off more or less instantly.

[avar]

You're just assigning magical value to "turn it off".

That's only a big deal with fossil fuels due to the fuel cost, the fuel cost of nuclear is marginal.

Yes, I agree that it's stupid to build a (big) nuclear power plant only to use it to boil an Olympic sized swimming pool most of the time.

But that's stupid because we're over-relying on "green" energy that can't provide baseload power.

It's even more stupid with fossil fuels, now you also need an entirely different backup infrastructure, but the fossil one pollutes much more than nuclear.

[hnaccount_rng]

The problem with your logic is, that nuclear is _only_ competitive with a 100% utilization rate/capacity factor. Only with these 90+% capacity factors do you get to competitive rates per kWh produced. Otherwise the initial CapEx is just too large, especially in a non-zero rate environment, as these plants are _already_ scoped/calculated/financed to 40 years. At 90+% capacity factor! That amount of CapEx is basically impossible without either very high earning potential (that’s why TSMC works. Everyone will just pay their price) or government backing (because then you don’t have to care about financing and optionality costs and can just pay for it with taxes). Neither one will be possible, at least in western societies

(And yes this ignores a certain amount of externalities, like the tendency of requiring large scale evacuations in their surroundings every second decade, but we can set that aside, as it’s irrelevant for the economic argument above)

[acchow]

Or powering GPU compute centers. When the grid needs more power, these dynamically power down (raise LLM generation prices)

[tuatoru]

Electrolyzing water to make hydrogen for ammonia (fertilizer) and industrial chemical feed stocks, please.

[notTooFarGone]

This guy doesn't understand nuclear

[helloooooooo]

How would they regulate fluctuations in demand? Nuclear can’t do that. You need storage, or a reasonably scalable generation medium. Nuclear as a base load is moot

[robocat]

> Nuclear can’t do that

You are repeating a myth.

Load following is used in France: https://www.oecd-nea.org/nea-news/2011/29-2/nea-news-29-2-lo...

It mostly isn't used in the US due to regulations. https://news.ycombinator.com/item?id=36254716

The reason load following is not generally used is because because the economics of nuclear (large fixed costs) favour base load.

[pydry]

You can technically use nuclear power plants as load followers in much thr same way that you can technically keep warm by setting $50 bills on fire.

Load following with a nuclear plant basically means provisioning a 2GW plant and then using, say, 0.5GW of that - throwing away the rest.

(since the vast majority of the cost is capex not fuel)

Every kilowatt hour produced by that 2GW power plant is already 5x the cost of a kilowatt hour produced by a wind farm. If you assume it is used for load following that goes from 5x-20x depending on capacity utilization.

Pumping water uphill (snowy 2, coire glas, etc) is way way WAY cheaper and the geography to do that is ridiculously common.

Electrolyzing water and storing hydrogen underground is way cheaper too, and can be stored for months cheaply.

[survirtual]

Nuke plant -> btc mining with excess load when load is not demanded Nuke plant -> consumers when in demand

Pretty easy equation, much more reliable and much more scalable and not subject to the whims of the elements / can be done anywhere and on any planet in the solar system.

[rcxdude]

BTC mining is the exact opposite of scalable: there's a fixed supply of BTC available to mining, so you can only pay for so many nuclear power plants with it. Even the entire bitcoin market cap is about enough for 20 nuclear power plants, optimistically (and that's ignoring the cost of the miners themselves, risk, etc, etc).

[bobthepanda]

It’s mentioned that it runs the equipment harder, and France did have to shut down a large number of plants for maintenance recently: https://www.bloomberg.com/news/articles/2023-03-11/french-nu...

[natmaka]

Load-following runs the equipment harder, indeed.

There are safety-related limits (power modulation proportion, duration of a pause needed after each modulation, modulations frequency...) to nuclear load-following capacity, and the very combustible status is a major parameter.

Pertinent document (French ahead!): https://www.sfen.org/rgn/expertise-nucleaire-francaise-suivi...

Quote: « un réacteur peut varier de 100 % à 20 % de puissance en une demi-heure, et remonter aussi vite après un palier d’au moins deux heures, et ce deux fois par jour »

Proposed translation: "a reactor power output can vary from 100% to 20% in 30 minutes, then after 2 hours can go back to 100% at the same speed, and can cycle this way 2 times per day".

This is quite a good performance when it comes to load-following (French engineers are very good at this), however it is insufficient in the real world (save any ridiculously expensive over-provision of nuclear reactor, most idling) and very weak compared to gas turbines performances.

Even in nuclear-packed France (which exports electricity) fossil fuels are also burnt in order to produce electricity since nuclear's inception, for most of the load-following and peak (about 9% in 2021), and it would be much worse without hydro. https://ourworldindata.org/grapher/share-elec-by-source?coun...

On the other hand green hydrogen (produced by intermittent renewables at over-electric-generation time) can be stored then used at insufficient-generation time.

[flextheruler]

Didn’t Germany just put its nuclear power plants on standby instead of shutting them down last year

[kuchenbecker]

Control rods modulate the output.

[fomine3]

Fuel cost is a somewhat minor cost for nuclear plants, so it's not much worth to do it

[malfist]

Not quickly

[flashback2199]

Not great, not terrible