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Is Nuclear Energy the Answer?

Posted on 13 June 2019 by scaddenp

Abbott 2011  and Abbott 2012 doesn’t think so but perhaps there are better analyses? For discussions of economics, levelized cost estimates of various electricity technologies can be found here and here.

Nuclear energy is quite commonly proposed as the solution to reducing GHG emissions. As soon as this gets raised on an article's comment thread, there has been a bad tendency for on-topic discussion to be completely derailed by proponents for and against.

We have repeatedly asked for nuclear proponents to provide an article for this site which puts the case based on published science but so far we haven't had a taker. The proposal would need to be reviewed by Sks volunteers. In lieu of such an article, this topic has been created where such discussions can take place.

However, in the absence of a proper article summarizing the science, stricter than normal moderation will be applied to ensure that all assertions made for or against are backed by references to published studies, preferably in peer-reviewed journals.

Update - October 2020

This post has been up for a little over a year now, and has received over 200 comments. Now seems like a good time to add some clarification.

First of all, the challenge to "nuclear proponents" to provide an article requires that the article "summarize the science". It is not the desire of Skeptical Science to provide a one-sided, pro-nuclear assertion. The expectation is that an article would provide a balanced review of all aspects of nuclear energy as a practical, affordable, realistic source of low-carbon energy.

If you think of yourself as a "nuclear advocate", then writing a balanced article will be difficult for you. This is not a place for "lawyers' science", where the role is to pick a side and pretend there is no other reasonable argument. This is not about winning an argument - it is about coming to a common understanding based on all the available evidence.

If you think that criticism of your position represents an "anti-nuclear bias", then writing a balanced article will be difficult for you.

If you think that you are the only one that truly understands nuclear energy, then you are probably wrong.

Review of any submitted article will not be at the level of a review of a professional journal article, but anyone submitting an article needs to be prepared to have their positions examined in detail for weaknesses, missing information, lack of support in the peer-reviewed literature, etc. If you find it tough to accept criticism in the comments thread, then you will not find review any gentler.

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Comments 301 to 350 out of 362:

  1. 'You keep posing conspiracy theories about governments sabotaging nuclear.'

    Hardly conspiracy theories. Governors Brown in California and Cuomo in New York, Prime Minister Naoto Kan in Japan, and Presidents Tsai Ing-wen of Taiwan and Moon Jae-in of South Korea, made no secret of their determination to close their respective nuclear industries. In Europe, Green parties have been demanding the energy portfolio in return for joining coalitions, and then closing reactors even when it means funding new gas plants or resurrecting coal.

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  2. Macquigg:

    I went to comment on your "more neutral forum" and I have been blocked. I only posted there once and did not violate the site rules.

    The moderators here allow nuclear posters. So much for your "neutral" forum.

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  3. Both renewables and nuclear decarbonize.

    Fell, H., Gilbert, A., Jenkins, J. D., & Mildenberger, M. (2022). Nuclear power and renewable energy are both associated with national decarbonization. Nature Energy, 7(1), 25-29. [Link]

    ...which is a response to flawed analysis found here:

    Sovacool, B. K., Schmid, P., Stirling, A., Walter, G., & MacKerron, G. (2020). Differences in carbon emissions reduction between countries pursuing renewable electricity versus nuclear power. Nature Energy, 5(11), 928-935. [Link]

    Nuclear is low carbon, on par with wind and solar, right?

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  4. Sekwisniewski:

    Analysis of lifecycle emissions of nuclear power compared to renewables by scientists generally indicate that nuclear plants emit 5-10 times as much carbon dioxide as renewables.  Nuclear industry sources find emissions are comparable.  Who do you believe?.

    Jacobson 2009 reviews the data at that time.   Since 2009 renewables have reduced their emissions while nuclear has not changed.  In addition, Jacobson calculates emissions due to opportunity cost.  

    It takes about 2-4 years to plan and build wind and solar plants.  It takes about 10-14 years to plan and build a nuclear plant.  For the entire time you are building the nuclear plant you have to use fossil fuels.  You save much more carbon by building the rapidly completed renewable energy plants.

    Since 2009 the cost of renewables has plummeted.  Nuclear costs have risen.  Nuclear reduces carbon much slower and at much greater cost.  For me that is not "on par" with wind and solar.   Some people do not care about time and cost and feel nuclear is comparable.

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  5. "Who do you believe?" - wow, so much science! What is going here, folks? Is this some kind of bait for trolls? This thread does not look like a serious effort to summarize knowledge on nuclear, so I don't think anyone will respond.

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    Moderator Response:

    [PS] As stated in the article, the primary purpose of this thread is to keep nuclear discussions away from other threads for people who want to talk about it. No one on the SksSc team has any particular expertise in the science of nuclear power though some frequent commentators here are well versed.

    SksSc would welcome guest contributions that are willing to focus on peer-reviewed papers. We would especially welcome any peer-reviewed rebuttals of Abbott. We are not particularly interested in the opinions of self-proclaimed experts that are not willing to back their assertions with reviewed references.

    Other sites are definitely a better place to discuss the economics, safety and politics of nuclear power.

  6. This 2021 paper refutes the conclusions of Sovacool et al. I don't believe the authors have any connection to the nuclear industry.

    CO2 emissions of nuclear power and renewable energies:
    a statistical analysis of European and global data

    'Our results are in complete contradiction to a recent publication (Sovacool et al. in Nat Energy 5:928–935,2020. The authors of this paper conclude that nuclear power does not reduce the CO2 emissions, but renewable power efficiently does. In addition, they argue that these two technologies crowd out each other. The possible reason for their claims may result from a specific conditioning of the data. In contrast, our analysis clearly confirms the adequacy of both nuclear and renewable power generation.'

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  7. John ONeill @306,

    You do your reputation no favours when you say of Wagner (2021) 'CO2 emissions of nuclear power and renewable energies: a statistical analysis of European and global data' that you "don't believe the authors have any connection to the nuclear industry." You appear not to even have noted that there was but one author. And had you checked you would find Frederick Wagner was an emeritus professor of Plasma Physics, so deeply connected to the technology, and that his commentary (eg here) shows his connections also to the industry. But that doesn't make his paper unreliable although it is good to read such work before nailing its colours to your own masthead, even if as in this case the battle is against a pretty easy target, which Sovacool et al (2020) certainly is. Maybe you have not noted that presented @303 is another swip at Sovacool et al., namely Fell et al (2020) 'Nuclear power and renewable energy are both associated with national decarbonization'.

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  8. John Oneil:

    In your post at 392 you claimed:

    "'Over the last 50 years, countries that adopted nuclear power consistently reduced emissions intensity, by more than three times as much as those that went without nuclear."'

    Your link was apparently not peer reviewed.  Your most recent links suggest similar reductions between nuclear and renewables.  My cite found renewables resulted in less emissions.  As I said at 296, I doubt we will agree on his topic since different papers reach different conclusions.

     Your citations only address emissions during the running of nuclear plants, the opportunity cost emissions of nuclear are about 10 times the total emissions of wind and solar due to the very long build times of nuclear.  They are calculated in Jacobson 2009, linked above at 304, and are the main reason Jacobson rejects nuclear as a future power source.  In addition, since it takes 10-14 years on average to build a single nuclear plant we would see no nuclear power from proposed plants before 2035.  That is after all electricity should be converted to low catbon.  2035 is too late.

    Nuclear is too expensive, takes too long to build and there is not enough uranium.

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  9. The mention of "opportunity costs" ties into what I suspected may be leading to the differences in estimates/opinions here.

    "Opportunity cost" is a common term in economics, and may need a little explaining. Let's say that I have $1000 sitting in a bank account, making 3% interest. One point of view is "hey, that's great! In a year, I'll have $1030! What a good investment!" But if a different investment vehicle will turn that $1000 into $1050 in a year, then I am actually losing out on $20 of lost income - $20 of money that could have been mine next year if I had switched investments. Although I think I am making $30 in the year, I have lost the opportunity to make another $20 - the "opportunity cost" of my current choice of investment.

    What Michael Sweet is saying is that the "cost" of nuclear needs to include the lost opportunity of reducing carbon emissions while we wait for nuclear to be built. The carbon emissions in the next 30 years will be either 30 years of wind built today, or 10 years of fossil fuels plus 20 years of nuclear if we say "but direct emissions from nuclear are as good or better than wind".

    Going back to the $1000 investment, are we further ahead if we invest at 3% for 30 years, or nothing for 10 years and 5% for 20 years? You need to include the opportunity cost of "nothing for 10 years" to make an accurate comparison.

    It's kind of like Popeye's friend Wimpy: "I'll gladly pay you next Tuesday for a hamburger today".

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  10. A few problems with the opportunity emissions of nuclear:

    1. if they are added to lifecycle emissions, they'd need to be subtracted from fossil emisions,
    2. nuclear may be built to replace aging nuclear (repowering),
    3. nuclear coming online in the future may cover new demand arising from clean electrification,
    4. any other source should have opportunity emissions added too.
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  11. A few problems with that list, sekwisniewski.

    1. It doesn't matter whether you label them as "nuclear' or "fossil". The emissions end up in the atmosphere.
    2. If nuclear is being built to replace existing nuclear, then it doesn't replace fossil-fuel-based capacity and does nothing to reduce fossil fuel emissions.
    3. Other sources coming on line now can also cover future demand.
    4. Yes. The calculations need to cover all sources of electricity, and all the CO2 emissions that are produced if a particular path is chosen. Cherry picking a compartmentalized view - where you only count emissions when a plant is operating (e.g., wind vs. nuclear) and you ignore how this fits into the overall picture - is a bad approach.
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  12. Replying to 311:

    1. You can't add opportunity emissions to lifecycle emissions, because it violates the conservation of mass, if those lifecycle emissions are then used to calculate physical emissions. 

    2. Another counterfactual to maintaining nuclear is replacing it with a mix of fossil and renewable sources. Fossil backup of renewables is suggested in Abbott (2012). Renewables replacing nuclear wouldn't reduce emissions either according to your logic, which does not seem to be a good framing.

    3. Yes, but when nuclear covers new demand opportunity emissions of = 0.

    4. Absolutely, we've got to take the overall picture into account, which is studied in the field of energy systems modeling.

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  13. Seriously, sekwisniewski? "Conservation of mass" arguments?

    Taking life-cycle emissions, using only what happens during construction and operation of the plant violates the "conservation of a consistent argument" requirement when looking at item 4. Either we are taking the entire system and results into account, or we are selecting only the part that supports a particular argument (AKA cherry picking).

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  14. Replying to 313:

    Of course, by definition the lifecycle emissions should account only for a given source (wind, solar, nuclear, hydro, etc) LIFECYCLE. Once we've established those, we could construct various scenarios of building those sources in time in an interacting system. Only then could we optimize and assess if there are "opportunity emissions" for different scenarios, i.e. does including nuclear bring us faster/cheaper to net zero or not? Still, these wouldn't be lifecycle emissions. Does this make sense?

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  15. sekwisniewski:

    I already said:

    It doesn't matter whether you label them as "nuclear' or "fossil". The emissions end up in the atmosphere.

    What matters is complete accounting. Item 4, which I think we agree on.

    "Getting faster to net zero" is not necessarily the issue. Minimizing total emissions between now and "getting to net zero" is what matters.

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  16. Replying to 315:

    Bob Loblaw:

    "Getting faster to net zero" is not necessarily the issue. Minimizing total emissions between now and "getting to net zero" is what matters.

    I did not intend to suggest otherwise and used "faster/cheaper" quantifiers as possible scenario constraints.

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  17. The difference between getting to net zero first versus minimizing the total emissions between now and reaching net zero is not a trivial distinction.

    Look at the following figure. The red line reaches zero after 40 years. The blue line has not quite reached zero after 60 years. The total emissions under the red line are about 3x the total under the blue line. Waiting 30 years for "better technology" is not a good choice.

    Getting to net zero

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  18. The graph with the concave blue line and the convex red line is actually a good cartoon of what actually happened to the electricity emissions of France and Germany, the exemplars of the 'Mesmer plan' accelerated reactor buildout, and the 'Energiewende' attempt to decarbonise with mainly wind and solar. French electricity emissions, and fossil fuel use, plummeted, and are still among the lowest in Europe, even though at the moment, the nuclear industry is only running at 34% of its capacity. Germany started later, its emissions have gone down much more slowly, it's still producing on average 3 to 4 times as much CO2 as France, and there's no guarantee that the reduction curve will get steeper - at the moment, it's not looking good, with mothballed coal plants being started up to replace the Russian gas that's supposed to be 'firming' solar and wind. Peak power production over the last 24 hrs was 69 GW, close to the full capacity of either solar, 65 GW, or wind, 64 GW. But solar averaged only about 11 GW, and wind only 14 GW. German nuclear, unlike French, has been running at 98% capacity all day. The batteries that will supposedly back variable renewables are nowhere to be seen. Pumped hydro makes an appearance for just four hours, at from 2 to 11% of demand. Meanwhile, the 'brown coal', of which Gemany is the world's largest user, continues to be the largest single source of electricity, as it has been for the last thirty

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  19. John Oneill:

    ...and if we had an expectation that the conditions that led to early development of nuclear in places such as France could occur again, and provide us with large quantities of nuclear energy in the very near future at reasonable/competitive cost, then nuclear would be a useful path in the future.

    But like they say in any investment advice, "past performance is not indicative of future results". You really need to make sure that the conditions that led to past performance will actually exist and continue in the future.

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  20. The current price estimate for NuScale power (the first modular reactor to propose building a plant) has been increased to $89/MWH.  That includes $4 billion in subsidies from the government and $30 per MWh from the Inflation Reduction Act (IRA).

    Typical utility scale solar installations currently cost about $24 per MWH in the USA although that also includes some subsidies from the IRA.  Perhaps the next proposed modular reactor will be able to reduce the price so that they are only a factor of two greater than solar power.

    For those new to the nuclear argument, NuScale said in 2008 that they would have operating reactors by 2020.  I doubt that the NuScale reactors will be built.

    Nuclear is too expensive, takes too long to build and there is not enough uranium.

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  21. David-acct:

    It is not my problem that you have not done your homework and do not know that France nuclear reactors shut down on weekends. From Wikipedia:

    "France's nuclear reactors comprise 90 per cent of EDFs capacity and so they are used in load-following mode and some reactors close at weekends because there is no market for the electricity.[59][10] This means that the capacity factor is low by world standards, usually in the high seventies as a percentage, which is not an ideal economic situation for nuclear plants."

    It is common knowledge among those who have done their homework that France generates too much nuclear power at night.  They sell some at a loss to their neighbors (presumably those who use cheaper solar during the day).  They shut down some reactors on the weekends since no-one wants the power.  

    In 2022 France generated approximately 279 TWh of nuclear electricity.  Their installed capacity was 61.4 GW.  I calculate their capacity factor at 51.8%.  They forecast generating about 330 TWh in 2023 which gives a capacity factor of 61% in the unlikely event that they make their forecast.  They have to shut down many reactors on hot days.  Will that work with record hot summers?

    Since nuclear reactors can't really load follow (in France they just shut them down on weekends), they generate too much power when load is low and not enough when load is high.  They average out the daily usage in the data youo show so that it appears that they generate more usable power than they really do.  They sell at night at a loss and buy during peak power at the highest prices.  France uses their reactors differently than other nuclear countries because they were stupid and over built their reactor fleet. 

    They have limited storage so they turn off the reactors.  In the USA the biggest pumped hydro storage plants were built to store nuclear power at night for use during the day peak.  Nuclear supporters ignore the immense cost of storage for nuclear reactors while exaggerating the cost of storage for renewable energy. 

    No current scientific groups studying future energy systems recommend building any nuclear plants.

    I recommend you read more background information (this thread would be a good start) so that you don't keep repeating long debunked nuclear myths.

    Nuclear is too expensive, takes too long to build and there is not enough uranium.

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  22. I posted this on another thread where questions were raised about nuclear.

    David-acct at 12:

    I went back and looked at your link to French electricity generation where you claim: :

    "This link from France's gov shows no such shutting down of nuclear on weekends."

    My emphasis. The days are not cherry picked, they are the only days I looked at. 8/10 is a Thursday and 8/5 is a Saturday.

    date time Power MW
    8/10 2:45 31645
    8/10 13:45 30424
    8/5 4:15 28489
    8/5 16:15 25548

    Several question about this raw data occured to me.

    1) You state clearly that the data shows no nuclear power stations were shut down. Please explain why the power generated on the weekend is so much less than the power generated on Thursday. How does this show that no power stations were shut down over the weekend? It appears to me that about 6 of 31 power stations (20%) were turned off.

    2) On both days they are generating more power at night when power is generated at a loss than they are generating during the day when the price of electricity is much higher. Can you explain why the "always on" nuclear plants generate less power during the most expensive part of the day than they do when electricity is cheapest?

    This example proves beyond doubt that examining cherry picked factoids without any analysis is a complete waste of time. Please do not cite raw data any more. You need to cite analysis of data that filter out gross errors.

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  23. I would like participants here to clarify one thing: "shut down."

    Growing up in France, I got to do school field trips to nuclear power plants. On these occasions, engineers would instruct us on basic elements of these plants' operation. A reactor is rarely "shut down" except for major maintenance or emergency/abnormal procedures. The reaction can be slowed, the reactor isolated from the rest of the system and/or generators taken offline, is that what we're talking about here? Otherwise it would imply taking the reactor below critical level and that is not practical if it is to be used again, especially on short notice.

    Slowing down the reactor can be necessary when cooling is an issue, when the weaather is already hot and they want to avoid spilling too much warm water in the environment. This has become more of a concern as river water temperatures have been increasing. It could be why power output is higher at night in August. Unless of course, these dates are under European format, which would place them in October and May.

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  24. Phillippe Chantreau,

    My understanding is that many reactors stop generating electricity on weekends for economic purposes.  Since France often has cooling issues on hot summer days, and they are reported to be in drought, a lack of cooling water could also contribute to less generation.  If a reactor was off line both days for cooling issues it would not have registered in the data I copied (a good reason not to do your own analysis).

    Here are my personal definations:


    If a reactor is taken off line so that it no longer generates electricity it has been shut down.  It does not matter what the reason is or if they keep the reactor hot so that it can be more rapidly started up again.  I do not know the Wikipedia defination.

    If a reactors power output has to  be reduced for any reason that is a partial shut down and is an indication that the reactor is an unreliable power supplier.  I note that nuclear supporters frequently claim that reactors are "always on".  

    What is your defination of shut down?  If they insert all the control rods the chain reaction stops. The decay of radioactive fission products continues to produce a very large amount of heat.  Enough heat to keep the boilers hot and requiring a large amount of water to prevent disasters.  For me that is completely shut down but a nuclear technician might have a different defination. 

    Do you have a link that describes what the French do on weekends to lower nuclear power output by 20%?  I would  also like to know why they generate less power during the peak periods than during the low at night.  I suspect waste heat is causing at least some of the decline (as you mention).

    My understanding is that some reactors are taken below the critical level.  The control of reactors is extremely complex so I could be incorrect.

    The dates are from August 2023.

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  25. I know next to nothing about nuclear reactors but I know coal-fired power stations well. When less power is needed then less coal is fed into furnace (making a mile of other adjustments especially to air flow and feedwater as well), so steam output is reduced. I would assume nuclear similarly slows output by slowing the nuclear reaction. To me, a partial shutdown is stopped one or more generation units not reducing steam output.

    All steam plants have to reject heat back into the environment to convert steam back to water, usually by cooling towers. High summer temperatures play havoc with this especially if there are restrictions on temperature of cooling water going back into rivers. This usually means easier (and more efficient) to generate at night. If close to limit, then you have to reduce power as the day warms up.

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  26. Scaddenp:

    My understanding is that it is much more difficult to ramp up/down a nuclear plant than a coal plant.  Some of the reaction products poison the chain reaction.  If you change the reaction conditions the balance between the chain reaction and poisoness elements in the waste also changes.  It is difficult to keep everything under control.  You cannot shut the reaction down and then start it up again immediately like a coal plant can.  In the USA none of the reactors can load follow.  In France some of the reactors can slowly ramp production (maybe 1-2% per minute).  It is hard to find references that describe how France lowers their production.

    Here David-acct claimed that nuclear plants ran 92% of the time at full power.  France currently has installed nuclear nameplate of 61.4 GW.  The highest capacity factor in the two days I looked at was 51.5% in the middle of the night.  The lowest was was 41.6% during peak power.   

    The point is that claims that nuclear plants are "always on" are easily demonstrated to be false.  Cold weather, hot weather, drought, flooding, nearby fires and other natural changes can all cause reactors to shut down on short or no notice.

    In a renewable energy world stored power will be most valuable.  Baseload power will not be valuable.  Baseload power that shuts down during peak times is very low value.  If the reactors in France were not owned by the government they would be bankirupt.

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  27. Michael,

    As you said yourself, you looked at 2 days of nameplate capacity percentage. Perhaps that is not quite enough to form a good perception of how the power mix is managed. I do not share your assessment, which I think is a little too hasty and lacking context.

    During the day, solar picks up considerably. Over a 24 hours summer day, it changes from 0% of the mix to over 20%. You looked at the percentage of nameplate capacity, but if flexibility is to be a part of the system, it is inevitable that this percentage be low during some periods. Solar picks up to 23% of the total capacity during the peak demand time of the days I looked at, and that was pretty close to the variation in total demand. It is therefore not surprising that nuclear's share be reduced, especially if waste heat is to be limited.

    This site shows generation by source as the data is compiled. I find the graph very interesting and the ability to compare time periods is handy too:


    It also shows that coal, gas and oil make up a very small percentage of the mix. Although GHG emissions were not the main concern when this system was developped, it did reach the goal of achieving a very low level of dependence on fossil fuels. That is a good thing, no matter what, under the circumstances that we are now facing.

    I do not see the ability to be flexible as a weakness. Flexibility was in the plans for a long time for the nuclear part of electricity in France. The increase in river water temperatures is what was not planned for. Design features can allow to exploit warm/hot water instead of discharging it, as has been done in Olkiluoto (albeit somewhat experimentally or small scale).

    These plants exist and generate enormous amounts of electricity without greenhouse gases production. They do have a useful role to play, and they can be succesfully integrated in a cleaner system:


    Flexibility is not a bad thing: 



    You seem to suggest that no new nuclear produciton should be added anywhere in the world. I think it is debatable and depends on local and grid factors. Of course there are problems that can not be ignored. Waste, safety, waste heat, vulnerabilities from natural factors. Every solution has problems and vulnerabilites. There is no free lunch.

    By the same token, the question that is the title of this entire thread is ill posed. There is no single solution to the problem we face. There is no silver bullet, but the fight is on and any ammo that has a chance of reaching a mark should be used. I do not see a massive ramp up of nuclear generation under the form we have it now (gen III reactors at best) as the solution, but it does not mean that there is no merit in the existing plants, or that new ones muct be banned under all circumstances. No way of generating electricity without producing CO2 should be discarded.

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  28. Phillippe Chantreau,

    This thread is now 328 posts long.  I maintain that nuclear electricity is too expensive, takes too long to build and there is not enough uranium to build more than a handful of plants. 

    The plants in Georgia cost over $30 billion to build and billions of dollars additional were charged to customers while the plants were being built.  They will each generate 1117 MW of power.  With a 90% cacpacity factor that will be about $15,000 per megawatt of power source.  In 2020 in the USA capacity weighted solar cost was about $1655 source. (It is less now).  You can build 10 times as much solar than nuclear for a billion dollars.  If you want the nuclear plant to be able to load follow you dramatically decrease the amount of power generated and increase the capacity adjusted cost.

    It takes 10-14 years to build a nuclear plant.  During that entire time you have to generate your power using fossil fuels.  Solar plants take only 2-4 years to build and often start generating when they are half built.  The CO2 pollution during constructiion of nuclear is more than the total CO2 cost of solar farms.

    The supply of uranium is limited.  There is not enough uranium to generate more than about 5% of world power.

    Informed people can disagree on what they think about nuclear.  I think that since nuclear is uneconomic, takes too long to build and there is not enough uranium that it is a waste of resources building any new plants.  The time and costs are already sunk for existing plants so if they can conpete economically they can stay (most existing  nuclear plants cannot compete economically). 

    If you think it is worth investing in expensive, slow, unsafe nuclear plants go for it.  It is a free country. 

    I don't bother to discuss nuclear waste, the safety of nuclear plants, hot water pollution and vulnerability to natural disasters because the economics of nuclear plants are so bad.  

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  29. sekwisniewski:

    Sovacool et al. have since published a reply to the supposed refutation, pointing to serious flaws in said paper:

    Sovacool, B.K., Schmid, P., Stirling, A. et al. Reply to: Nuclear power and renewable energy are both associated with national decarbonization. Nat Energy 7, 30–31 (2022). [Link]

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  30. I am responding to Cork here.

    At post 9 in the linked thread you said:

    "Converting Uranium only plants to thorium /uranium plants would reduce many of the issues"

    When I pointed out that it is impossible to substitute thorium into existing reactors you backpedeled and said at 11 

    "Maybe not today, maybe tomorrow"

    Maybe you should read more of the background on nuclear so that you don't propose more impossible solutions.  Why should I consider anything you say when you start off proposing impossible solutions and then change the goal posts when I call you out?  We don't need thorium reactors, we have wind and solar.

    Thorium does not accumulate in large economically recoverable reserves.  You would be better off trying to recover uranium from the ocean, another impossible task.

    I remember reading about cheap nuclear power designs in Scientific American when I was 15.  They sounded good.  All failed spectacularly.  I am now 65 and nuclear engineers can no longer fool me with their fantasies.

    In France their reactors are falling apart and they have to shut down during the hottest parts of the day when demand is highest.  "Always failing" describes it best.  They have not paid off the loans they took out to build their reactors 40 years ago.  If they were a private business they would have been bankrupt decades ago.

    Bill Gates claimed in 2006 that they would have running reactors in 2020.  17 years later they do not even have a design ready to submit to the regulators.  They gave up on their original design as hopeless and have a new design they hope will be complete someday in the distant future.

    Solar is the cheapest energy in the world with wind as its only compeditor.  Public money spent on nuclear is simply wasted.  That money should be spent installing solar and wind or buiding transmission lines to make the grid stronger. 

    China installed about 100 GW of solar capacity last year alone.  World nuclear capacity has been flat since 2000.  There is not enough nucear under construction to replace existing old plants as they retire.

    Nuclear is too expensive, takes too long to build and there is not enough uranium.

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  31. Per Michael's remarks, it's certainly a curious thing that we continue vigorously debating nuclear power's role as a central player in energy supplies even as it's been outpaced by events. 

    Along the lines of trying to identify a signficant role for Newcomen steam engines— in the year 1900, when triple expansion steam engines were fully evolved. 

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  32. By their fruits ye shall know them. Finland recently switched on its long-delayed Olkiluoto reactor, and promptly joined the select group of countries and regions with power emissions below 100 grams CO2 equivalent/kWh.

    Average for August -

    Finland 67g (47% nuclear)

    France 43g (78% nuclear)

    Germany 370g (37% wind and solar)

    California 282g (25% wind and solar, 9% nuclear)

    Ontario 98g (58% nuclear)

    South Australia 245g (58% wind and solar)

    California's only remaining nuclear plant was saved at the last minute - Governor Newsom realised his state was heading for blackouts. Ontario has recently announced plans to build four small modular reactors - plus four large reactors.

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  33. On Wednesday Nuscale cancelled their plant in Idaho.  That was the most advanced project of small modular reactors in the western world.  The price of the power was too high, even after the government spent over $600 million on the project.  It was supposed to be built on a location that used to have a fossil plant so water intakes and electrical connections to the grid were already built.

    Nuclear is too expensive, takes too long to build and there is not enough uranium.

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  34. This peer reviewed paper fron 2021 in IEEEaccess reviews the issues with small modular reactors.  They conclude that SMR's will be at least twice as expensive as large reactors and the rest of the claims by SMR supporters are simply a bunch of stuff.  It is unlikely that more than a very few demonstration reactors will ever be built.  Those that are built will be paid for by governments.  I note that the nuclear indusry has made many claims over the past decades that were a bunch of stuff.

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  35. I think you're confusing the Nuscale proposal with Bill Gate's planned Terrapower reactor in Wyoming, Michael. Nuscale was to build at the desert site of Idaho National Laboratory, which has had plenty of test reactors built, but no real power plants. The consortium of local power suppliers who'd agreed to proceed at $58/MWh baulked at $89. (Offshore wind projects on the East Coast are suffering the same fate, as materials price rises lead to a consumer backlash.)

    Terrapower's proposed Natrium plant in Kemmerer, Wyoming, is the one to go next to a former coal plant. It's a much more radical design than Nuscale's, but with pretty deep pockets funding it. One of the reactors its design was based on did run at Idaho National Lab - the Experimental Breeder Reactor II. EBR2 had no electrical generation, and its heat output was only a fortieth of Natrium's, but it ran fairly trouble-free for thirty years.

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  36. John ONeil:

    Are you addressing my link at 334?  If you read the link it describes all modular reactors as costing at least twice as much as large reactors.  This is due to economies of scale.  Modular reactor supporters claim that by manufacturing thousands of reactors they will be able to learn by doing and reduce the cost of manufacture.  I note that this does not happen most of the time in the nuclear industry.   

    The link provides analysis that shows it is virtually imposssible for modular reactors to be produced at the low prices that supporters claim.  In addition, the costs of renewable energy continue to rapidly decrease.  Modular reactors are trying to compete with coal.   Coal is already too expensive compared to renewables.

    I note that Terrapower claimed they would have operating reactors by 2020.  They have not yet submittd a design to the regulators.

    I note that there is no process for disposing of the sodium coolant after it becomes radioactive.

    Nuclear power is too expensive, too slow to build and the materials do not exist.

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  37. “The Westinghouse AP300™ Small Modular Reactor is the most advanced, proven and readily deployable SMR solution. Westinghouse proudly brings 70+ years of experience developing and implementing new nuclear technologies that enable reliable, clean, safe and economical sources of energy for generations to come.
    Our AP1000® reactor is already proving itself every day around the globe. Currently, four units utilizing AP1000 technology are operating in China, setting performance records. Six more are under construction in China and one AP1000 reactor is operating at Plant Vogtle in Georgia while a second nears completion.” ?

    Contents snipped

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  38. "I note that there is no process for disposing of the sodium coolant after it becomes radioactive." - michael sweet wrote at 337.

    Metallic sodium coolant can be converted to sodium carbonate and disposed as LLW (Low-Level Waste), which was done with previous sodium-cooled reactors. Source: Nuclear Waste Attributes of SMRs Scheduled for Near-Term Deployment Nuclear Fuel Cycle and Supply Chain (2022) by Argonne National Laboratory, pages 17-19.

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  39. Sekwisniewski,

    Perhaps I should have said there is no approved method of disposal of the sodium waste.  Given that there is no approved repository for the existing  high level waste either, perhaps that is no reason to worry about.

    I note that Terrapower originally had a completely different design that they gave up on.  Terrapower has not applied for a design certification yet.  Design certifications normally take 2 years or more.  How does that fit into Terrapowers' plan to start construction this year?  Where are they going to get the 16.5% enriched uranium now that Russia (the only current supplier) is constrained due to the Ukraine war?  It takes many years to develop a new fuel chain.

    According to your link the Natrium reactor would generate 345 MWE.  SMR's are generally described as under 300 MWE.

    I would prefer to delay any discussion of modular reactors until they have at least applied for design certification.

    My first argument is always that nuclear is not economic.  I am waiting for a cost estimate for the first natrium reactor.  Bill Gates will be able to foot the cost, but that does not mean it will compete with renewables.

    Nuclear is not economic, takes too long to build and there are not enough rare minerals.

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  40. Natrium is not designed to compete with wind, but to complement it. I believe Warren Buffet has an interest in it, and his fund also owns large wind farms in Wyoming. Unlike most reactors, Natrium does not depend on selling steady base-load power. The sodium from the hot end is 200C hotter than the steam from a conventional light water reactor, and is to be run through a heat exchanger to heat a store of nitrate salts, as pioneered by solar thermal plants such as Ivanpah in California. The nitrate salt is pumped from a cold tank to a hot tank, both insulated, and is a much cheaper way to store energy than batteries. When the wind's blowing, the whole output of the reactor goes into filling the hot tank. When the wind dies, the reactor's output is used to heat steam for a turbine, as is the hot salt. The plant produces nothing when the wind's blowing, and prices are low, but when the wind drops and spot prices rise, it can make 50% more than its maximum nuclear output for as many hours as the hot tank lasts.

    Whether it will be economic is another story, but Kemmerer welcomes employment to replace the coal plant it's losing. The proposed Nuscale plant, in contrast, was to be in the middle of nowhere. The regional suppliers who had agrred ten years ago to put an option on it can get plenty of power from gas, but they expected a carbon price to penalise that. No carbon price eventuated. 

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  41. John ONiel,

    The Natrium plant can only store about 2 1/2 hours of the plant power output.  It can only generate 50% more power for 5 1/2 hours.  That is not really load following.  The overwhelming majoriity of the time it will have to run full out competing directly with renewable electricity producers.  You need to read the details of the proposal instead of just the industry propaganda sheets.

    I am surprised that you consider the Nuscale location to be "in the midddle of nowhere" compared to Kemmerer.  Kemmerer is the seat of county government with a population of 2,414 in 2020.  That is hardly a booming metropolis.  There are no towns with a poppulation over 12,000 within 100 km.  The biggest employer is the coal power plant that is shutting down.  The Nuscale location must have a few people to support the Idaho National Lab.  It appears to me that it would be difficult to be further "out in the middle of nowhere" than Kemmerer.  Where will the workers building the plant stay for the seven years of construction?

    Whenever I examine nuclear supporters claims closely I find that they are not supported by the data.

    Nuclear is not economic, takes too long to build and there are not enough rare minerals.

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  42. I would add, at least battery storage has the benefit of arbitrage (storing cheap renewables during peak generation to sell back later), whereas, nuclear is just expensive. Period. The only benefit I can see is relative to overall demand, where battery storage may run into deployment problems at full scale. Perhaps there nuclear can take up some of the available slack.

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  43. Pacificorp East, which owns the Kemmerer plant, has 7.5GW of coal capacity, and made 47% of its power from coal, 23% from gas in 2023. Wind and solar combined totalled 25% over the year. Like most grids, its power profile shows an evening peak, with a relative drop overnight, a pattern the Natrium reactor could follow. Wind over the last eight days in the area has been producing 6-7% of power produced, versus 20-30% for the seven preceding days - not the kind of variation that could be easily covered by batteries. Daily solar over the last month has varied from 2.09% of the area's production to 6.51% ( @Electricity Maps)

    If the reactor proves successful, there are plenty of other areas where a coal plant could be replaced by nuclear, especially one with the potential to load follow, and eventually to run on transuranics and depleted uranium.

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  44. John, to my mind you are still not addressing the key - why would you invest money in expensive nuclear rather than cheap renewables with storage? What wind and solar are producing now isn't the relative no. The question is what could they produce for the same money spent on the nuclear plant?

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  45. It's not what they are producing now, it's the extreme variation between what they produce at different times, and always will do. Solar obviously varies from zero to ~100% of its capacity on its best day, at any one time, but also by not much less, averaged over longer periods. Wind's minima are not so low, but even places in the trade wind belt have months well below the average. Mawson Staion in Antarctica, which is battered by near-constant catabatic winds (strong enough to destroy one of the wind turbines there), still has a calmer season. Modern economies facing loss of power are not analagous to reptiles - they can't just shut down for a while. Proponents of solar celebrate yearly records in capacity, but their predictions of a corresponding decrease in fossil use, or even of coal use, fail every year (covid excepted.) Fossil fuels still make up about 80% of energy use, as they have done for the last forty years, and they continue to grow every year. A few places have managed a majority of electric power from wind and solar, always backed up by either hydro, or imports of fossil-generated electrons. Academics such as Mark Jacobson's Stanford group, or the Lappeenranta University team, confidently predict 95% plus of all mankind's energy will be from wind and solar; so far work on huge sectors such as transport, steel and fertilisers has hardly even begun. That being so, why would you not support at least research on an energy source that is already larger than wind and solar combined, and that is the primary power source, not just for low-population examples such as Uruguay, Iowa and South Australia, but for major economies like France, Ukraine and Ontario ? Which three, incidentally, have all recently committed to a major expansion of their already large nuclear sectors.

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  46.  It is difficult to reply to a post filled with so many half-truths and mistakes.  All your claims have been shown to be false upthread.

    1) As you pointed out, Jacobson and hundreds of other researchers have shown that an all renewable energy system (primarily wind and solar) can support the entire economy.  It will cost trillions of dollars less than fossil fuels and save millions of lives.  Your mentioning a few days with low wind is simply fake news.  Since you provide no links to support your wild claims I will not link any either.  There are several countries that generate essentially all of their electricity using renewables, a technology that has only been installed widely for less than10 years.  France had to purchase a boatload of expensive electricity from its neighbors during the electricity crisis because their reactors failed.  I note that no energy researchers support using nuclear power as the primary energy to power the world.  Few or no researchers support using even a small amount of new nuclear energy in the future.

    2) Your claim that nuclear power "is already larger than wind and solar combined" is deliberately false.  According to Our World in Data, in 2021 wind and solar produced 2900 TWH of electricity and in 2022 wind and solar produced 3422 TWH of power world wide.  That will increase by at least 15% in 2023.  In 2021 nuclear produced 2750 TWH of power and in 2022 nuclear power produced only 2632 TWH of power.  The amount of power produced by nuclear has not increased significantly for over 20 years.  It is unlikely that the amount of nuclear power will increase for at least 10 years and it is more likely to decrease substantially as old reactors are shut down.

    3) Why would a sane person suggest pouring more public money into a failed technology like nuclear?  The "new" modular reactor proposals are old designs that were rejected in the 1950's and 1960's as uneconomic or simply too difficlut ot build.

    4) Projections of 2024 energy use are that renewable energy will be built at a fast enough rate to reduce world wide carbon dioxide emissions.  After 70 years nuclear provides less than 4% of all energy in the world and has not helped reduce carbon emissions for over 20 years.  I note that 70% of primary power produced by nuclear is wasted heating the surroundings versus essentially zero waste heat using renewables.

    5) Your claim work on using renewables for "transport, steel and fertilisers has hardly even begun" is simply false.  Nuclear has not done anything to address these technologies.  I, and millions of other people, already drive an electric car.   More electric cars are sold every year.  Electric trains are widespread.  Electric heavy trucks are being manufactured.  It is easy to make ammonia fertilizer from renewable energy.  Steel is being made with electric furnaces and using green hydrogen.  As more and more renewable energy is built it will be used for those purposes since renewable energy is cheaper than fosil fuels.  Since renewable energy has only been the cheapest energy for about 5 years there has not yet been time to build out a completely new power system yet.  After 70 years nuclear cannot even keep up with its current production as old reactors are retired.  

    6) Nuclear power in France was down by 50% last year. At all times in a system with nuclear power they require at least enough spinning reserve to cover for the sudden shut down of the reactors because nuclear reactors are prone to unplanned shutdowns at any time. This is not needed for renewables since they do not shut down with no notice. Ways to control for down transmission lines are still required.

    7) Nuclear is a failed technology.  It is too expensive and takes way too long to build.  Due to economies of scale, smaller, modular reactors will be more expensive than big reactors that are already too expensive to compete with renewable energy.  Since reactors take so long to build, the entire electrical system will be renewable before new nuclear designs are ready to be widely built.  I do not even need to mention that there is not enough uranium in the world to power more than 5% of all power, an insignificant amount.

    Whenever I examine nuclear supporters claims closely I find that they are not supported by the data.

    Nuclear is not economic, takes too long to build and there are not enough rare minerals.

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  47. Sorry, nuclear, as you cite, only provides more power than either wind or solar separately, not together. Also as you say, it hasn't done much to cut emissions for the last twenty years, largely because in the west none was being built, and fairly successful efforts were going on to shut down those plants already existing. Whether wind and solar will manage to do so this year, we shall see.

    Figures for wind and solar production were from Elecricity Maps, which I can no longer access on my computer, only on my phone app. You could try You'll be pleased to see that since Jan 26, when wind only made 3% of Wyoming's power, it's been picking up, to about a quarter, and emissions are correspondingly down, to 'only' 580grams CO2/kWh.

    If you're charging your electric car off Florida Power and Light, 23% of it last year would have been from nuclear, 5% solar. Gas did the rest. Supposedly those gas plants are to be converted to hydrogen in the next decade or so. 

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  48. John... "largely because in the west none was being built..."

    Don't you think that was primarily because it's hard to attract investment when, once built, these plants wouldn't be able to produce electricity at a competitive price? Even if projects are claiming they can produce at a lower cost, they're very far from proving that out.

    In the meantime, wind and solar continue to scale exponentially

    If you're an investor in energy markets it seems pretty darned clear where the best place to put your capital is. 

    As I said before, I think there's perhaps a place for some nuclear. I know there are going to be people out there insisting it's going to work. I'd just say that's a long, tough row to hoe.

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  49. Electricity is a natural monopoly, and its supply is a service, not a commodity. The introduction of the auction system for supply was pushed by Enron, which expanded like a cancer through the natural gas markets during the 90s, got a foothold in power through Oregon-based West Power, and proceeded to game the industry till a series of blackouts, massive power price increases, and financial scandals lead to its downfall. Enron also introduced large-scale wind into the US - after its bankruptcy, Enron Wind was the only surviving American wind manufacturer, and was bought by GE. Wind's erratic fluctuations are a natural partner for gas. Its alleged low price is for the developer - the power user pays it the same price as whatever supplier was needed to produce the last watt on the grid. Wind often bids negative prices, secure in the income from production tax credits and renewables mandates certificates. The increasingly-frequent negative wholesale prices seen, usually around midday, on high wind and solar grids are not shared by the customer at the end of the month.

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  50. "why would you not support at least research on an energy source that is already larger than wind and solar combined..."

    Current capacity of nuclear is completely irrelevant to whether it is a good investment or not. Latest LCOE from Lazard:  Note that solar plus storage beats nuclear. This way to deal with wind is either storage or integrated grid system over distance of at least 1000km.

    You are welcome to invest your money any way you like, but don't be surprized if other people reading the numbers decide that nuclear is waste of money.

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