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Nuclear Power in France

world-nuclear.org

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Re: Nuclear Power in France

#281

Post by p_l »

Manuel_D wrote: post #239
derriz wrote: post #225

Earlier quoted context omitted.

Nuclear plants are also "intermittent" - the average US reactor spends 32 days offline per year. Does that mean a grid relying heavily on nuclear needs massive amounts of storage? No - it means you need to have redundant capacity which is the solution also used for wind and solar. The benefit of nuclear in this regard isn't that it's "non-intermittent" - it's that the most common failure modes for a nuclear nuclear a…

A capacity factor of over 90% is exceptionally good. Wind and solar are 35% and 25% respectively [1]. And this down time for refuelling and other tasks is scheduled in advance. This not at all comparable to solar and wind's uncontrollable intermittency. A nuclear grid requires vastly less overproduction than a renewable grid. As you point out, renewable sources end up falling back on fossil fuels to pick up the slack…

and in many places capacity factor for Solar is much lower than that

IIRC, for Poland, we're talking about needing to build 10GW worth of solar generation to get 1GW into grid on average, or 4GW of wind. Assuming ~24GWh of storage to make it capable of providing that 1GW continuously.

Re: Nuclear Power in France

#282

Post by 01100011 »

godelski wrote: post #254
01100011 wrote: post #97

Earlier quoted context omitted.

I remain a supporter of democracy but do have serious doubts regarding the ability of the majority of humankind to maintain a sufficient understanding of the increasingly complex world they control. Large portions of the US population seem to have problems with basic reasoning skills. I'm not sure the school system or western culture is capable of rectifying that anytime soon.

I think the bigger issue is that everyone feels they need to be an expert on every subject. Look at any of these conversations on nuclear and/or climate. Climate is the most complex problems humans face today yet we all pretty much act like we're experts and all pretend it's purely political will to solving the problem. Even on a tech forum where the average person is much more tech literate these beliefs and actions…

> I think the bigger issue is that everyone feels they need to be an expert on every subject.

I think people tend to view the world through the lens of their experiences. Lots of us are basically technicians these days, even a good percentage(the majority maybe) of software "engineers". I think it's easy for people to achieve some mastery in a domain and begin to believe that other aspects of the world are also similarly mastered. I'll say that most of my life I fell into that camp. I'm somewhat gifted with technology and I let my successes in the simplistic world of programming(and it really is pretty simple if you're just following recipes and calling libraries) bias my view of the world. I think my descent into libertarianism in the 00's was largely fueled by that erroneous thinking.

It's only after working on harder problems that I've come to appreciate the limits of my thinking, and the limits to which I can step into another domain and outthink the experts within it.

I think there are a lot of folks who have never worked on something subtle and complex, and to them the world is just so simple. Certain people/substances/ideologies are just purely good and others are purely evil, with no thought to the complexity of the actual world we inhabit.

> The problem isn't that the world is getting more complex. The problem is that we're unwilling to admit it.

Exactly. We better learn quick or we'll be like a toddler holding a hand grenade.

Re: Nuclear Power in France

#283

Post by p_l »

eldaisfish wrote: post #89
toomuchtodo wrote: post #53

Earlier quoted context omitted.

Renewables have zero marginal cost to generate. When the spot price goes negative, they can simply stop exporting. Other generators are paying others to take power and for the fuel they're using to generate. As renewables penetration increases, it only puts more pain on legacy generators and increases the arb opportunity for storage (which can charge when power is cheap, and discharge when demand is high). This is th…

tesla's service does not scale to gigawatts and gigawatt hours. Battery storage works for minutes of demand, not hours. At the moment, any battery tries to profit from arbitrage, not supplying continuous load. You mention zero energy prices but fail to address the major problem - reliability. The power is always on and losing power is catastrophic. The solution to the current problem is more transmission capacity. No…

While of course oversimplified, https://model.energy is interesting site to simulate the issues, as it tries to model a "base load" generation using green energy. The moment the storage costs of hydrogen go beyond ridiculously low (based on assumptions of available salt caverns), or if you try to use batteries only, the numbers game is over for non-nuclear - unless you add gas turbines which defeat the 0-emission target.

For a simulated replacement of 2GW power plant (2-3 reactors, enough to provide for a metropolitan region base load, assuming Poland for weather/solar data) using only batteries for storage, we look at needing to build:

  ~29GW of solar power
  ~12GW of wind power
  ~46.7GWh of battery storage (with ~3.5GW output)
Going for hydrogen storage, the result is

  ~10.2GW solar
  ~6.5GW wind
  ~5.5GWh battery (with 0.98GW output)
  ~1.5GW hydrogen gas turbine
  ~760GWh hydrogen storage.
All of that, to replace a 2GW power plant with non-nuclear zero emission sources. (for comparison, polish base load demand is effectively around 14GW, and we don't really have any place for more pumped storage or hydro power without some funky exclusion zones and environmental destruction)

Re: Nuclear Power in France

#284

Post by masta »

nitrogen wrote: post #88
masta wrote: post #26

What the site does not seem to talk about is that an internal commission in 2011 found[1] that the real cost per kWh is around 50-56c. Nuclear power in France is heavily subsidized, directly and indirectly. [1] https://bit.ly/3DAGW2s

Do you have a non-shortened/non-tracking link?

Page is in German: https://taz.de/Kosten-der-Atomkraft-in-Frankreich/!5101723/

Re: Nuclear Power in France

#285

Post by godelski »

01100011 wrote: post #282
godelski wrote: post #254

Earlier quoted context omitted.

I think the bigger issue is that everyone feels they need to be an expert on every subject. Look at any of these conversations on nuclear and/or climate. Climate is the most complex problems humans face today yet we all pretty much act like we're experts and all pretend it's purely political will to solving the problem. Even on a tech forum where the average person is much more tech literate these beliefs and actions…

> I think the bigger issue is that everyone feels they need to be an expert on every subject. I think people tend to view the world through the lens of their experiences. Lots of us are basically technicians these days, even a good percentage(the majority maybe) of software "engineers". I think it's easy for people to achieve some mastery in a domain and begin to believe that other aspects of the world are also simil…

I think that's kinda the path I followed too. Once I started working on really hard problems that racked my brain (problems that take months to solve _after_ I've gained expertise in the area) I started thinking about the world differently and seeing how nuanced it is. That first order approximations weren't enough to make even remotely reasonable approximations. I remember in one of my jobs my friend told me "there's a book on o-rings that's over a thousand of pages. O-rings. Just one simple device." Nuance matters a lot. It's the difference between a space shuttle exploding and not.

In a way, it is also liberating. I don't have to know everything. I can know to trust experts in the field. I know how to vet experts in fields adjacent to mine. And importantly, I know how to ask nuanced questions to people outside my field and to lean on them for help understanding problems I'm not an expert in.

Not that I don't also get egotistical and overstep my bounds. I definitely do. But it no longer hurts (as bad) when someone calls me out on it. It is more about the passion to learn now and getting rid of bad habits. Being called out now is an opportunity to learn.

Re: Nuclear Power in France

#286

Post by lazide »

cinntaile wrote: post #273
lazide wrote: post #267

Earlier quoted context omitted.

I take it you didn’t read my earlier comment? There is no engineering reason for those reactors to cost $10bln. Literally zero. There are lots and lots of other reasons why they will probably cost even more than $10bln/ea though. Just like there is literally zero engineering reason for the ‘high speed’ rail in California to cost the insane sums it is currently consuming, and will continue to consume. The reason why t…

Life is pretty darn good in lalaland where everything is just a technological problem ready to be solved. I wish I could live there.

Not sure how me pointing out that organizational and political dysfunction, corruption, and general bullshit is the reason why it is 'hard' now (and wasn't as hard 50 years ago when the currently active reactors were built since folks seemed to actually want to build them more than just siphon money out of the system or throw wrenches into the works for ideological reasons), and how it doesn't seem to have anything to do with any of the actual technical or engineering difficulty is living in lalaland - but you do you I guess?

If we wanted to build cost effective and safe reactors, we could, and have many times in the past. Near as I can tell, almost no one does (compared to some cool new idea, or what becomes a one off, or ends up going back to the drawing board 50 times - all while getting paid), so we don't.

Same with high speed rail (and a bunch of other pork projects in CA), same with subways in many big cities, etc.

Re: Nuclear Power in France

#287

Post by nehalem501 »

derriz wrote: post #179
Manuel_D wrote: post #133

Earlier quoted context omitted.

Comparing non-dispatchable sources with dispatchable sources is comparing apples to oranges. Solar is cheap, until you saturate daytime consumption and have to start building storage. Similar with wind.

Nuclear isn't dispatchable - most reactors have a design output and are not intended to be ramped up and down. They require a big chunk of actual dispatchable power (natural gas mainly) to provide demand following. LACE is a measure which takes into account the value of the generated electricity as well as the cost of production but nuclear does poorly here also as much of its output occurs when wholesale prices are…

French reactors can adjust their power outputs in 30 minutes between 100% and 20% their nominal power rating. I think we are actually the only country doing this. (EDF: "In France, a nuclear power plant is able to ramp up or down between 100% and 20% of nominal power in half an hour, and again after at least two hours, twice a day.", source https://hal-edf.archives-ouvertes.fr/hal-01977209/document bottom of page 4)

Re: Nuclear Power in France

#288

Post by nickik »

orwin wrote: post #154
nickik wrote: post #108

Earlier quoted context omitted.

There has been a lot of research into this. The main thing is actually learning effects, the second thing is 'mass production'. If you have teams that have build reactors before, they will be much better. Once you have people on their 3rd reactor, they go fast. Its kind of like other massive infrastructure projects like bridges. Basically nuclear reactors are large civil engineering projects, and you need experience…

The reason why we still use PWR is because of pilotability. When you're able to modulate the power of a reactor of 40% in 30 minutes without damaging anything or engaging any failsafe, you can reasonably make nuclear reactor follow the consumption.

PWR are not actually good at that. In theory, with a liquid fueled reactor you should be able to be almost completely load following. Most GenIV reactor that are trying to go threw regulation is able to load follow at least as good or better then PWR.

The reason we mainly use PWR is because the military wanted them for submarines and the government and industry had a massive program them into commercial use. From there we got a large amount of legacy, knowledge and infrastructure around them.

After 3 Mile Island the nuclear regulatory system changed and regulation were made technology specific. So even if you wanted it would be practically impossible to get a license for anything else. Thankfully this has now been realized and they are changing their regulation to make them less technology specific.

Re: Nuclear Power in France

#289

Post by nickik »

oezi wrote: post #120
nickik wrote: post #98

Earlier quoted context omitted.

I think all of those are not really true when we are thinking about modern plants that you would build if you were really serious. If you really go into nuclear today you would try to use something like Terrestrial Energy Molten Salt reactor or something like that. - Nuclear kills less people, that is worth some tiny risk - Nuclear waste is actually a resource for the future. You can get things like nuclear batteries…

Nuclear at this point is dead in the water. The upward trajectory of renewables is so strong that building nuclear plants is no longer viable. If anybody would change course now and start planning and building new nuclear plants it will be at least 10 years before these go online. By this time wind and solar will be another magnitude cheaper and nuclear will not be able to compete.

So your logic is, only wind and solar can improve and nuclear can never improve.

Re: Nuclear Power in France

#290

Post by felixlechat »

ronnier wrote: post #3
redm wrote: post #2

"Government policy is to reduce this to 50% by 2035." I'm no expert on Nuclear power but it seems to me were going in the wrong direction. At a time when we're investing so much money in other fuels, we could be investing that in better nuclear power, like Small Modular Reactors [1], Sodium Cooled Fission, Small Pellet reactors, etc. [2] [1] https://www.energy.gov/ne/advanced-small-modular-reactors-sm... [2] https://…

China is investing in nuclear power. https://www.forbes.com/sites/jamesconca/2021/04/23/china-wil... > As of this month, China has 49 nuclear reactors in operation with a capacity of 47.5 GW, third only to the United States and France. And 17 under construction with a capacity of 18.5 GW. None have been shut down. Nuclear provides only 2% of China’s electrical power now, but the country intends nuclear to eventually…

Nuclear provides 4.8% of China's electrical power [1] in 2020 and 2% of China's energy mix.

[1] https://ourworldindata.org/grapher/share-elec-by-source?coun...

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