First new US nuclear reactor in decades enters commercial operation in Georgia • Hacker News Board

Re: First new US nuclear reactor in decades enters commercial operation in Georgia

#341

Post by Manuel_D » Tue, Aug 01, 2023, 10:51 PM UTC

Retric wrote: post #338

Manuel_D wrote: post #335

Earlier quoted context omitted.

2-6 hours is nowhere near enough to offset daily fluctuations, let alone seasonal fluctuations. Overproduction only gets you so far, unless this proposal also involves transoceanic HVDC cables. Hydropower is not exactly the same thing as storage: you can stop releasing water and build up the reservoir, but you cannot pump water up river. Even just 6 hours of storage -which would not be sufficient even with several fa…

Overproduction means you don’t ever see daily fluctuations you have a surplus every single day of the year. Unless storage gets insanely cheap that’s by far the cheapest safe option. Hydropower dams are already storage. When you don’t release the water it’s saved until you do. If you have enough rain from 3 months ago to release 10 MW 24/7 over a week then you also have enough water to release 15 MW for 12 hours and…

> Overproduction means you don’t ever see daily fluctuations you have a surplus every single day of the year.

No, this is not even remotely true. No amount of solar overproduction will let you produce energy at night. 12 hours a day (on average, depend on the season) you will not have any production regardless of overproduction. You'll have a lot of excess energy during the day, but still no energy when the sun has set. Infinity times zero is still zero. Not unless you create transoceanic HVDC cables that connect Eurasia to the Americas, literally piping electricity from one side of the world to the other. Wind also has windless days, with more extreme seasonal fluctuations. Overproduction is not a silver bullet that eliminates the need for storage. Just because you have net surplus over the course of a 24-hour period does not mean demand was satisfied at all times. This is why intermittent sources are so challenging.

> Hydropower dams are already storage. When you don’t release the water it’s saved until you do.

But you can only save energy at the rate that rainfall refills the dam. If you have a dam that refills at a rate of 10MW, you can only effectively store 10MW of excess energy. If you have 20MW of excess production, you can still only store 10MW and the other 10 MW is wasted. Dams are not batteries, they can store a lot of energy but they can only be refilled at the rate dictated by rainfall.

You also can't completely shut off a dam or the river will run dry with serious ecological consequences, and impairing downstream water supply.

Re: First new US nuclear reactor in decades enters commercial operation in Georgia

#342

Post by pfdietz » Tue, Aug 01, 2023, 11:01 PM UTC

pas wrote: post #339

pfdietz wrote: post #326

Earlier quoted context omitted.

Laws have changed a lot since the AEC existed.

without looking up we can easily bet that anti-nuclear activists did their share of lawsuits to try to get those new laws applied to the plant, so there have been reviews.

One very important milestone was the Calvert Cliffs decision in 1971, applying NEPA to nuclear construction. This was while the AEC still existed, though.

https://en.wikipedia.org/wiki/Calvert_Cliffs%27_Coordinating...

Re: First new US nuclear reactor in decades enters commercial operation in Georgia

#343

Post by 10g1k » Tue, Aug 01, 2023, 11:05 PM UTC

pfdietz wrote: post #231

10g1k wrote: post #143

My 2c: Why nuclear power is a dumb idea. Countries with nuclear reactors: 32. Countries which have had nuclear leaks or meltdowns: 15. Number of nuclear leaks and meltdowns since 1952 (only those which resulted in loss of human life or >US$50K property damage): ~100. About 60% of those have been in the USA, allegedly the most advanced country in the world with the bestest regulation of such things. Note that the USA…

The 300 years comes from the length of time the waste remains self-protecting against amateur diversion of plutonium. After that time, the fission products have decayed so much that the gamma rays are, conservatively, too weak to inhibit such diversion. It's not that waste canisters can't last more than 300 years, it's that something has to be done with the waste by that time so there's no point requiring they be cer…

The 300 years came from a specification I read, produced by the US government, for the design and construction of the canisters used to contain the waste. This was many years ago, and may have been updated.

Re: First new US nuclear reactor in decades enters commercial operation in Georgia

#344

Post by _hypx » Wed, Aug 02, 2023, 1:22 AM UTC

pfdietz wrote: post #340

_hypx wrote: post #334

Earlier quoted context omitted.

A lot of that is just anti-nuclear propaganda. Nuclear in France does not have major problems.

I'm sorry, you don't get to dismiss inconvenient facts by calling them "propaganda".

There's no such thing as a perfect solution. The problems people keep on bringing up are minor and do not qualify as serious problems.

Re: First new US nuclear reactor in decades enters commercial operation in Georgia

#345

Post by pfdietz » Wed, Aug 02, 2023, 10:42 AM UTC

preisschild wrote: post #291

chroma wrote: post #149

Earlier quoted context omitted.

Fukushima shows that even early nuclear reactors are incredibly safe. You take an aging plant based on an outdated design, construct it in an unsafe location, then hit it with the fifth-largest earthquake ever recorded, then hit it with a 20 foot high tsunami, and then it explodes ... and what were the casualties? One worker and maybe 50 early deaths due to cancers. A typical coal power plant kills more people every…

> maybe 50 early deaths due to cancers No long term deaths have been recorded yet.

They will never be recorded, because they are lost in an ocean of cancers that normally occur from other causes. That doesn't mean regulators can ignore them. Radiation is not a criminal defendant who must be presumed innocent until proven guilty.

Re: First new US nuclear reactor in decades enters commercial operation in Georgia

#346

Post by pfdietz » Wed, Aug 02, 2023, 11:57 AM UTC

Manuel_D wrote: post #256

pfdietz wrote: post #251

Earlier quoted context omitted.

Seawater extraction is even less plausible than breeders. The polyamidoxime fibers that article discusses do not have sufficiently long service lives. Also, if the uranium were to be burned in PWRs, the effective power per ocean area of uranium collectors would be much less than the effective power/area from photovoltaics. Uranium is a small fraction of nuclear's cost at current uranium prices. But eventually that ru…

Again, the energy density of uranium is such that even if seawater extraction remains expensive, it has negligible impact on nuclear power costs: https://en.m.wikipedia.org/wiki/Economics_of_nuclear_power_p... > The cost of raw uranium contributes about $0.0015/kWh Even if this increases by an order of magnitude, this is not significantly impacting the cost of nuclear power. Heck, even two orders of magnitude still a…

If lithium increased in price by 100x, we'd switch over to one of the many other options for energy storage. If uranium increases in price by 100x, burner reactors are screwed (well, even more screwed than they already are.)

Re: First new US nuclear reactor in decades enters commercial operation in Georgia

#347

Post by Retric » Wed, Aug 02, 2023, 5:42 PM UTC

Manuel_D wrote: post #341

Retric wrote: post #338

Earlier quoted context omitted.

Overproduction means you don’t ever see daily fluctuations you have a surplus every single day of the year. Unless storage gets insanely cheap that’s by far the cheapest safe option. Hydropower dams are already storage. When you don’t release the water it’s saved until you do. If you have enough rain from 3 months ago to release 10 MW 24/7 over a week then you also have enough water to release 15 MW for 12 hours and…

> Overproduction means you don’t ever see daily fluctuations you have a surplus every single day of the year. No, this is not even remotely true. No amount of solar overproduction will let you produce energy at night. 12 hours a day (on average, depend on the season) you will not have any production regardless of overproduction. You'll have a lot of excess energy during the day, but still no energy when the sun has s…

Excess per day doesn’t mean you get solar power every single second just per day, that’s what batteries are for.

> But you can only sacs energy at the rate rainfall refills the dam. > can’t completely shut off

You’re completely misunderstanding how dams are used look here: https://en.wikipedia.org/wiki/Hoover_Dam

Installed capacity 2,078.8 MW, Capacity factor 23%

Minimum flow rate isn’t 0, but is plenty low enough to have a great deal of flexibility.

Re: First new US nuclear reactor in decades enters commercial operation in Georgia

#348

Post by Manuel_D » Wed, Aug 02, 2023, 6:01 PM UTC

therealdrag0 wrote: post #275

Manuel_D wrote: post #250

Earlier quoted context omitted.

Hydro is indeed clean in that it does not emit greenhouse gases. Sure, it disrupts life around the dammed waterway. But that's way less of an impact than climate change.

Hydro emits huge amounts of GHG when flooded organic matter decomposes btw.

This is a one-time overhead emission, and I doubt it's "huge" compared to even a small amount of fossil fuel use.

Re: First new US nuclear reactor in decades enters commercial operation in Georgia

#349

Post by Manuel_D » Wed, Aug 02, 2023, 6:54 PM UTC

Retric wrote: post #347

Manuel_D wrote: post #341

Earlier quoted context omitted.

> Overproduction means you don’t ever see daily fluctuations you have a surplus every single day of the year. No, this is not even remotely true. No amount of solar overproduction will let you produce energy at night. 12 hours a day (on average, depend on the season) you will not have any production regardless of overproduction. You'll have a lot of excess energy during the day, but still no energy when the sun has s…

Excess per day doesn’t mean you get solar power every single second just per day, that’s what batteries are for. > But you can only sacs energy at the rate rainfall refills the dam. > can’t completely shut off You’re completely misunderstanding how dams are used look here: https://en.wikipedia.org/wiki/Hoover_Dam Installed capacity 2,078.8 MW, Capacity factor 23% Minimum flow rate isn’t 0, but is plenty low enough to…

> Excess per day doesn’t mean you get solar power every single second just per day, that’s what batteries are for.

...which would require an enormous and infeasibly large amount of batteries. You're right: overproduction doesn't mean you get power for every second per day. But a grid does need sufficient energy at every single second per day or you have blackouts. This is why overproduction of intermittent sources is not as useful as it sounds.

Nothing in your link about dams contradicts what I wrote: their rate of recharge is limited. You can shut off much of the turbines and let the reservoir build up, but they cannot be recharged faster than the rate at which rainfall refills the reservoir. Judging by a 2 GW capacity and 23% capacity factor, one would infer that it's refilled at a rate of ~500 MW (in reality, less than that since Lake Meade is shrinking). Completely shutting off the turbines would only refill at a rate of 500 MW. If you have 2 GW of overproduction, you can't refill Lake Meade with 2 GW of potential energy. You can shut down its turbines and let the reservoir refill at a rate of 500 MW, but the other 1,500 MW can't be used to recharge Lake Meade.

A dam is sort of like a battery but its rate of recharge is much more limited than it's rate of discharge, which is a big disadvantage when trying to capture the overproduction from intermittent sources.

Re: First new US nuclear reactor in decades enters commercial operation in Georgia

#350

Post by therealdrag0 » Wed, Aug 02, 2023, 7:17 PM UTC

Manuel_D wrote: post #348

therealdrag0 wrote: post #275

Earlier quoted context omitted.

Hydro emits huge amounts of GHG when flooded organic matter decomposes btw.

This is a one-time overhead emission, and I doubt it's "huge" compared to even a small amount of fossil fuel use.

In comparison to FF it’s small of course. But it’s billions of tons, globally more than Germany’s footprint. Which is larger than most peoples assumptions, hence the “huge”.