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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Recent Comments

Comments 4001 to 4050:

Shalom Wulich at 04:44 AM on 18 June 2022

Antarctica is gaining ice

Hi Philippe,

If your replly was to me then:

1. What is significant is irelevant to my questions since I'm raising 2 concerns. Why a when a wrong model trend of Antarctic sea ice is not mentioned and why Arctic sea ice is ? Why arent the the full picture of trends is discussed.

2. Alternatively why was it so important to show a model forcasting dramatical reduction of Antarctic sea ice (also if it's irelevant, why bother) but once measured data arrives and it doesnt fit the model abandon this Antarctic sea ice and dont mention it in the SPM ?

Crookall21649 at 04:30 AM on 18 June 2022

EGU2022 - A personal diary from a science enthusiast perspective

Terrific post, Baerbel - you really captured the essence of it all. Many thanks too for:

Helping to convene EOS1.8 Climate & ocean literacy;
Your presentation in EOS1.8 Climate & ocean literacy;
Helping to chair the Townhall Meeting TM8.

Philippe Chantreau at 01:26 AM on 18 June 2022

Antarctica is gaining ice

When this myth was addressed, there was a small upward trend of Antarctic sea ice, that was squeaking by the statistical significance criteria.

As of now, the Antarctic sea ice long term trend in the satellite record is difficult to distinguish since the margin of error is more than twice as large as the trend(!): 0.6% +- 1.6% per decade.

Incidentally, 2022 saw the lowest Antarctic sea ice extent in the satellite record.

https://nsidc.org/data/seaice_index

None of this really affects the basic argument in this myth rebuttal, which is that the loss of land based sea ice is a concern for sea level rise, whereas variations in sea ice are not.

The data does not allow to identify any significant long term change at this time, although what has been happening since 2014 certainly seems interesting.

Shalom Wulich at 23:35 PM on 17 June 2022

Antarctica is gaining ice

1. You mentioned that Antarctic sea ice is irrelevant. As if saying "Lets focus on the Antarctic land ice we are losing".

2. I'm wondering why is this trend not relevant but other are. Why dismiss any trend that shows different behaviour than expected.
3. By saying expectedI see that the models for arctic sea ice fit well with measured trend while models for Antartic sea ice got it wrong. So can you comment on why the model for Antartic sea ice got it wrong and is the same model used also for Arctic ?
4. Comment 3 is also is clearly inline with Key section from IPCC Assesment Report "AR5", 2014 where it accuratly reports trends of sea ice in Arctic but dont mention the different trend in sea ice in Antartic. Why did IPCC include the Arctic sea ice (i.e. it's relevant) but omitted the Antartic sea ice (i.e. you seem to claim it's irelevant). Do you thing it's because it interfers with the main message which implys that "ice is melting dramatically"

Thanks,

Shalom

Shalom Wulich at 23:35 PM on 17 June 2022

Antarctica is gaining ice

1. You mentioned that Antarctic sea ice is irrelevant. As if saying "Lets focus on the Antarctic land ice we are losing".

Thanks,

Shalom

One Planet Only Forever at 14:13 PM on 17 June 2022

A durable U.S. climate strategy … or a house of cards?

It is indeed incorrect to claim that only one issue matters or that one action will be the solution to a complex multi-faceted problem like the diversity of harm and destruction being caused by human pursuits of impressions of success and status relative to others.

However, the authors appear to have missed the harmful influence power of the science of misinformation and disinformation marketing.

"Deny, Deceive, Delay: Documenting and Responding to Climate Disinformation at Cop26 and Beyond by King et al., Institute for Strategic Dialogue" highlighted in "Skeptical Science New Research for Week #24 2022" is recommended reading. I have not completed reading it. But the 7 specific Policy Asks presented appear to be an important focus for implementation by elected representatives wanting to correct the harmful reality that has developed due to a lack of such policies.

I would add that the authors need to be careful when using the term Freedom, like their statement "The price of freedom, human health, and planetary health is constant vigilance on these and many more issues." Freedom has become weaponized to include the freedom to believe whatever is desired to excuse doing whatever is desired. It should only be "Freedom diligently governed and limited by the pursuit of increased awareness and improved understanding of how to be less harmful and how to be more helpful to others who need assistance". The authors may have intended that understanding. But what needed to be said could have been said without using the term Freedom -> 'Developing a sustainable healthy diversity of human societies fitting in as part of a robust healthy planetary environment ...' says what needs to be said without invoking the now weaponized Freedom term.

Evidence 'limits what can be sustainably believed'. Evidence limits Freedom of belief. And the ethic of Do No Harm further limits Freedoms. Contrary to the preferred beliefs of the delayers, deniers and doubters, the required corrections of what has developed have been correctly exposed by climate science. The science correctly limits what can sustainably and justifiably be believed and claimed. And it indicates the required rapid correction of the over-development in harmful directions due to the delay in corrective actions through the past 30 years. And pushing for that rapid change is required from leaders 'even if it is believed to be impractical' (50% of car sales in the USA being electric by 2030 is required). 'Setting lower bars' is the scam of the delayers that has so successfully developed the much more massively harmful and challenging current problem. The delayers need to lose some of their 'harmfully hard won status'.

Perhaps another Policy Ask would be along the lines of: Have elected representatives removed from office, not rely on 'the next election' to correct things, if they make repeated public declarations, or take repeated actions, in their roles as leaders that are contrary to 'pursuing increased awareness and improved understanding of what is harmful and how to limit harm done and help those who need assistance' (if they show a resistance to learning to be less harmful). Alternative Truth based harmful misunderstandings need to be kept from influencing the actions of leaders.

One Planet Only Forever at 07:36 AM on 17 June 2022

Skeptical Science New Research for Week #23 2022

The report “Cost increase in the electricity supply to achieve carbon neutrality in China” is indeed a robust evaluation of the likely future costs of electricity after the correction of the market failure free-riding by harmfully exploiting non-renewable fossil fuels. The resistance to rapid correction of the market failure is making the situation worse for the future generations than it has to be. And the most important, and most powerfully resisted (or attempted to be ignored), understanding is that energy consumption and other consumption, needs to be reduced with the highest per capita consumers leading the correction to less consumption. More ‘less harmful consumption’ can be worse that the status quo (a case in point is Alberta increasing oil sands operations excused by the new things having ‘lower emissions per unit of production’ while the already built stuff is permitted to continue be more harmful).

The full evidence-based cost of harmlessly using fossil fuels (paying to fully neutralize the harm) should have been the market pricing requirement all along. The costs would have steadily increased as the evidence of the harms were identified (no need to try to develop popular support for imposing a carbon tax today). Instead the socioeconomic-political system failed by ‘permitting harm to be done’, then deeming that what was permitted cannot be made to be corrected in a way that is detrimental to those who had developed substantial benefits from the harmful activity.

The current generation of humanity faces the daunting task of correcting the massively incorrectly produced results of that massive market system failure. And climate scientists have faced the challenge of being understood, being faced with vicious significant resistance to their improved understanding becoming common sense knowledge. Perceptions of advancement or superiority due to burning fossil fuels are harmful misleading if they can’t be continued without continued fossil fuel use. But demands that the ‘correction of the harmful results of the market failure’ must not reduce developed perceptions of advancement or superiority remain intensely irrationally harmfully popular.

And, indeed, it is likely that the higher cost of electricity after the transition to net-zero would not just apply to China. The following is the electricity generation mix and electricity generation per capita for several nations (electricity generation data is from Our World in Data. Population data is from Worldometer):

% Coal (fossil fuel generation/total generation TWh) [Total TWh/million]
Norway 0.03% (<1.0/151=<0.7%) [151/5.42=27.9]
Sweden 0% (2/171=1.2%) [171/10.1=16.9]
Canada 5.5% (106/623=17%) [623/37.7=16.5]
USA 21.6% (2509/4157=60%) [4157/331=12.6]
Australia 50.8% (174/247=70%) [247/25.5=9.69]
New Zealand 5.4% (10/45=22%) [45/4.8=9.4]
France 1.05% (49/549=8.9%) [549/65.3=8.4]
Germany 28.8% (272/574=47%) [574/83.8=6.85]
China 63.6% (5664/8460=67%) [8460/1439=5.88]
Denmark 15.1% (8/33.4=23%) [33.4/5.8=5.76]
Italy 5% (167/283=59%) [283/60.5=4.68]
South Africa 84.4% (198/230=86%) [230/59.3=3.88]
Brazil 4.1% (120/640=19%) [640/213=3.0]
India 73.7% (1313/1697=77%) [1697/1380=1.22]

South Africa, India and Australia have high coal generation percentages like China. But all fossil fuel generation, not just coal, needs to be ended soon. And that indicates that the US, Italy and Germany also have a major generation transition challenge like China’s. And a significant concern could be the high per capita electricity generation of nations like Norway, Sweden and Canada.

I listed the nations in order of electricity generation per capita for a reason. A better future, and advancement of humanity, can be understood to have less per capita energy use and less per capita consumption of resources. That ‘improvement understanding’ would require renewable energy systems to operating in ways that minimize consumption of non-renewable resources (ideally fully recycling the non-renewable resources) and not produce accumulating harmful consequences (no problems getting bigger). That would only be achieved by competition for popularity or profitability if there is significant monitoring and governing that pursues improved awareness and understanding of how to minimize harm done and help those needing assistance.

But, of course, there is much more to understand about why electricity is being generated. The very high value in a nation like Norway may be close to being a valid minimum amount of electricity generation for a nation to have all of its members live at least a basic decent life. Alternatively, it could be due to large amounts of electricity used for an activity like fossil fuel extraction and exporting (like happens in Alberta, Canada where I live – a province with a population that is comparable to Norway). Given the history of free-market consumerism and aspirations for the luxuries of higher status, it is likely that a significant amount of unnecessary consumption is occurring in high electricity consuming nations like Norway (and regions like Alberta).

Returning to the evaluation of the future situation in China. The study’s authors based their work on China’s 2050 annual electricity demand being 14,900 TWh (200.9 PWh is reported to be 13.5 times China’s 2050 electricity demand). For the current population of China that would be 10.3 TWh/million (on the high side of current consumption per capita). But the population in China is expected to peak soon and decline by 2050. The BBC Futures article "Could China’s population start falling?” indicates that China’s population may peak this year (or peaked last year) almost a decade earlier that forecasts made in 2019. The indicated 2021 population of 1412 million as the peak would mean China’s 2022 population will be 37 million lower than presented by WorldoMeter (which are based on UN Population Division estimates). And research referred to in the BBC Futures article indicates that China’s population peak will be followed by a decline of 1.1 percent per year (down to 587 million by 2100). That decline raises the question of the wisdom of over-building a more expensive to build renewable energy capacity if global total population will be declining soon (The recent report in The Lancet "Fertility, mortality, migration, and population scenarios for 195 countries and territories from 2017 to 2100: ..." indicates that global population is likely to peak at less than 10 billion near 2060).

China’s population in 2050 would be approximately 1030 mllion (based on a peak of 1412 million in 2022 and an annual decline of 1.1%). That would mean an approximate 2050 electricity demand of 14,900/1030=14.5 TWh/million. That would put China up to the levels of the highest consuming nations rather than seeing China, and the highest consuming nations, target developing to be closer to 5-7 TWh/million.

As indicated in the study report, renewable electricity will likely cost more. However, reducing energy demand will reduce some of the costs identified in the study. It would reduce the costs of excess demand for manufacturing components. It would also reduce the cost of system integration components. And reduced energy consumption would reduce the costs of a person’s lifestyle by having reduced energy to pay for and having that reduced amount of energy cost less.

In Summary:

Developing sustainable solutions is unlikely to happen if something easier and cheaper is allowed to compete and compromise the pursuit of doing things less harmfully and more sustainably. That aligns with a fundamental ethic of engineering – the limitations on the risk of harmful results are not to be compromised by something that is cheaper or easier. Anything failing to pass the ‘limits of harm’ requirements is not a viable alternative regardless of how much cheaper and easier it is to be more harmful. (note that a profit bias can harmfully compromise the limits of risk of harm that are established to govern the actions of engineers).

It is important to be aware that sustainable ways of living almost always ‘Cost more and require more personal effort than getting away with harmful less sustainable alternatives’. The related understanding is that more sustainable ‘renewable energy’ can be expected to be more expensive than less sustainable alternatives, even if the alternatives are called ‘green solutions because of a claim that they do not produce ghg emissions’. Note that nuclear fission consumes non-renewable non-recyclable resources and produces accumulating harmful impacts).

Also, this relates to the donut eating analogy for fossil fuels presented in the SkS OPs Planetary Dieticians and Planetary Diet:

In the developed system, equally enjoyable less harmful replacements for donuts will likely cost more than donuts. And they will also need to be limited because with the developed preferences of the system the alternatives to the donut will still be harmful or unsustainable.
Not everyone can have as much as they want. But some people will make the mistake of consuming more of the less harmful alternative because it is less harmful so more is OK isn’t it? The objective is zero harm. Not just less harm. And the objective certainly isn’t as much harm as you can afford, especially when Other people will be suffering the harm ‘you can afford’.
The most advanced highest status humans already have the ability to enjoy eating in ways that are significantly less harmful. But they also have to learn to live without harmful eating, ending their temptation to eat harmful things. And they con do it because they have access to the Best Dieticians and Personal Cooks to be able to enjoy nutritious harm free food and beverages. They can live donut free. But the poorest struggle to get their basic energy needs. And they can be stuck eating as much of whatever harmful anti-nutritious, understandably more harmful than beneficial, donuts they can find to eat. And some of the poor are so mistaken that they believe that they will have a better life if they eat more donuts (because they see the highest status people eat donuts).

In spite of the harmful actions not being essential to survival for the highest status people, it is challenging to correct something that has developed a perception of being essential or, because of massive market failure, has become almost locked in as temporarily essential to survival. It is hard to correct harmful developments in competitions for popularity, profit, status and power. And it is even harder to take away the benefits, including the benefits of perception of higher status, that were obtained via the harmful unsustainable activity and related misunderstanding.

Haiburton42 at 14:20 PM on 15 June 2022

A durable U.S. climate strategy … or a house of cards?

"Will be with us for centuries. . . "

I want to. . . Debunk this, one minute . . .

Too often youth movements are not seen as the catalysts of change that they are.

catalyst: ????????✔️

a person or thing that precipitates an event.

"the governor's speech acted as a catalyst for debate

When, time and time again, the Old While Male wins a Utah election I'm thinking, "Oh, look, now it's raining all of their to do lists. . . And cats. . . ?"

M-m-meow.

I'm saying. . . That. . . This problem will be with us for centuries is not really an accurate statement in the grand scheme of things when . . . "TIME" is a variable we are ALL aware of.

"What. . . Is. . . . This. . .?

If we lead you follow."

https://youtu.be/u46HzTGVQhg

One cognitive process that contributes to this effect is Confirmation Bias, where people selectively seek out information that bolsters their view. In one experiment, people were offered information on hot-button issues like gun control or affirmative action. Each parcel of information was labelled by its source, clearly indicating whether the information would be pro or con (e.g., the National Rifle Association vs. Citizens Against Handguns). Although instructed to be even-handed, people opted for sources that matched their pre-existing views. The study found that even when people are presented with a balanced set of facts, they reinforce their pre-existing views by gravitating towards information they already agree with. The polarisation was greatest among those with strongly held views.1

One Planet Only Forever at 12:42 PM on 15 June 2022

Planetary Dieticians

This is a good analogy. However, building on my Planetary Diets comment, the context for the dietician’s work should be expanded to be working with multiple people. And one of the objectives would be to help reduce the collective harm of avoidable future demand for health care services or other needed future adaptations or attempts to repair the avoidable harm.

In that context, the resistance of learning (lack of change of behaviour) of some patients would cause the dietician to pursue understanding of the likely developed motivations of the patients which would be influenced by the environment they developed in. Consumption-based competition driven by popularity and profit should be expected to develop powerful resistance to governing that would limit the pursuit of enjoyment and status. And it is worse if there is misleading marketing that scientifically tempts people to harmfully over-develop primal instinct-based harmful misunderstandings. That scientifically driven system of misleading marketing can promote desires for sweet, fat and salt in the pursuit of profitable popular harmful over-consumption. Examples include:

a culture development like the ‘Reward of Birthday Cake’ (the donut being like that reward)
enjoyment of salty snacks at a bar (causing you to desire more beverages)
a cultural development like being impressed by a large piece of unhealthy fatty meat (fatty fish in moderation can be a helpful part of a healthy diet)

The dietician would become aware of the harmful desires for more consumption of whatever is perceived to be enjoyable or perceived to indicate higher status. Those desires could motivate people to resist changes that reduce their perceptions of enjoyment or status. And some people can become so harmfully tempted that they irrationally declare that they will only behave better if new things are developed that they perceive to be equally or more enjoyable, and cheaper and easier, than their harmful developed preference.

If the individual is determined not to learn to limit harm done to themselves then there is little that the dietician can do to help them. Updated monitoring and explanations of the results will continue to be denied and dismissed until the patient personally suffers horrible consequences that shake them out of their developed pattern of desired harmful misunderstanding.

That leads to understanding the dilemma of the reality of higher costs for renewable energy compared to the misleadingly low costs of fossil fuel energy. Fossil fuel costs are misleading because the costs do not fully neutralize the harmful impacts. The specific case of electricity is highlighted in “Cost increase in the electricity supply to achieve carbon neutrality in China” presented as the lead item on the Skeptical Science New Research for Week #23 2022. I will make a more extensive comment about that there.

scaddenp at 06:39 AM on 15 June 2022

What role for small modular nuclear reactors in combating climate change?

macquigg - Sks space is refutation of myths with peer-reviewed science. Other sites dealt more effectively with political and economics. To my mind, a useful site for discussion of nuclear is one where nuclear scientists and engineers contribute and back their claims with peer-reviewed paper not references to blogs and opinion pieces. The opinions of practitioners vested in the industry are difficult to evaluate without peer review.

The climate controversies were not helped by people without any domain knowledge (and often wikipedia-level physics) making wild speculations and theories. I dont think an accurate evaluation of risk and benefits of nuclear power is going to come from atmospheric physicists.

macquigg at 04:04 AM on 15 June 2022

What role for small modular nuclear reactors in combating climate change?

Michael, I have said nothing about the scientific consensus on nuclear power. Please stop trying to make me your strawman. This debate is not about me. I am here to collect critiques for the Discussion pages on some articles in Citizendium. To avoid long, inconclusive debates we are summarizing the best statement from each side, focusing on just one issue at a time. If you want to raise new issues, like “no long term repositories exist”, please make that a separate issue. I will add it to our numbered list.

5) Lyman's statement about all MSRs requiring on-site processing. See my last statement on this issue at post 27. I did NOT claim that generally means all. Another strawman.
I will assume from your response at post 34 that we agree, the quote from Lyman’s paper is complete, accurate and not taken out-of-context, and that the response from ThorCon’s engineer is factually correct.
https://citizendium.org/wiki/Talk:ThorCon_nuclear_reactor#Risk_of_proliferation
We disagree on how to interpret Lyman’s words “All MSRs chemically treat the fuel”, and “generally require on-site chemical plants”.
Even if we alter the quote, changing “all” to “generally”, the ThorCon response is still correct: “ThorCon does no chemical processing online to remove fission products or anything else.” Also, I think the altered quote would still be untrue. I am familiar with three MSRs (ThorCon, Elysium’s FC-MSR, and LFTR). Only LFTR uses on-site chemical processing. I think we should leave the quote on Citizendium as is, and let the reader decide what it really means.

2) Non-fuel waste
https://citizendium.org/wiki/Talk:ThorCon_nuclear_reactor#What_about_non-fuel_waste
I have just added this:
Answer from World Nuclear Association discussion of Recycling and reuse of materials from decommissioning:
Decommissioned steam generators from Bruce Power in Canada
"These steam generators were each 12m long and 2.5m diameter, with mass 100 tonnes, and contained some 4g of radionuclides with about 340 GBq of activity. Exposure was 0.08 mSv/hr at one metre." This compares to a chest x-ray (0.02 mSv) or the minimum exposure to show a measurable increase in cancer risk (100 mSv) XKCD Radiation Chart

I am still trying to get numbers on the ThorCon reactor. I have talked to engineers at ThoCon and one who was in charge of decommissioning a big PWR. They tell me that the irradiated steel is not a big problem. Cutting is done underwater, and the pieces are handled the same as spent fuel. Nobody is being evasive here. We just can’t get experienced nuclear engineers to jump only a few days after kerfuffle in academia.

You said I “cannot find anyone who can contradict [the Krall] paper in the PNAS written and peer reviewed by experts with over 200 years of experience designing reactors.” I gave you two links in comments 9 and 10 above. Here is another:
https://www.terrestrialenergy.com/wp-content/uploads/2022/06/Letter-to-PNAS-22-06-03-final2.pdf - response from David LeBlanc, Chief Technology Officer, Terrestrial Energy; “IMSR’s actual predicted thermal neutron flux at the reactor vessel is over 1,000 times lower.” than Krall assumes.

Who are these reactor designers you say reviewed the paper? Apparently not the engineers familiar with the designs. The reviews are still rolling in, and Dan Yurman is updating his webpage:
Stanford's Questionable Study on Spent Nuclear Fuel for SMRs | Neutron Bytes

4) Material resources. I have posted your question on beryllium to our Discussion page. On the hafnium question, do we really need to worry about this? Do you really think reactors can't be built with some other material in the control rods? Are you aware that some MSRs don't even have control rods? Helium is not an issue for this reactor.
Uranium supply should be a whole separate issue. WNA has a section on Uranium Resources: https://world-nuclear.org/information-library/nuclear-fuel-cycle/uranium-resources.aspx

6) The NuScale controversy. Looks to me like a miscommunication over an issue that doesn't really matter. They are arguing about maybe a factor of two at most in a small volume of waste that is easily managed. Let’s put this question aside until we resolve #2, and let’s stop calling people dishonest.

MA Rodger at 20:58 PM on 14 June 2022

UAH atmospheric temperatures prove climate models and/or surface temperature data sets are wrong

knaugle @4&5,

As we are commenting on SkS, perhaps it would be appropriate to note that Cowtan's "Temperature plotter" is one of the resources provided here at SkS.
And do note that UAH TLTv5.6 data only runs to July 2017 so any trend comparison using more recent dates (so an end date beyond 2017.6) will be comparing apples and oranges. For Jan 2000 to Jul 2017 HadCRUT5 (not on the trend engine) yields a trend of +0.226ºC/decade, pretty-much as per GISS & BEST.

You note the OP above hasn't been updated for a while. The 20 min video mentioned by Eclectic @6 doesn't really explain why UAH TLT 5.2 evolved into UAH TLT 5.6 and then into UAH TLTv6.0. And at one point the video actually uses the table shown in Fig 1 of the OP above.

Post-v5.2 (& I am no expert but if you are interested there is a UAH log of work done which shows one side of it), the evolution of UAH TLT to become 5.6 apparently does still include being driven by folk outside UAH observing problems and the UAH folk taking a long time to notice and to admit it was a problem and then to correct the problem.
Thus v5.3 arrived in 2010 addressing a spurious annual cycle which had been known about in 2008 but apparently first spotted back in 2003.
But much of the difficulty and thus the incrementing versions is down to the performance of individual satellites.
UAH TLTv6.0 appeared in 2015 and strangely UAH are more interested in proclaiming a new lower rate of warming than explaining what the new version is adressing. But perhaps not so strange if you watch that video.

michael sweet at 12:54 PM on 14 June 2022

What role for small modular nuclear reactors in combating climate change?

Macquigg,

You are mistaken. Scientists overwhelmingly oppose nuclear power. The last group studying future energy systems that supported nuclear power gave up on nuclear in 2021. The debate is over. Abbott 2012 is accepted by the scientific community.

2) Krall et al 2022 have shown that small reactors generate much more radioactive waste and it is a disastrous problem. We have not even discussed Krall's claim that the fuel waste from many modular reactors cannot be processed and stored in currently planned long term repositories (no long term repositories exist). You cannot find anyone who can contradict a paper in the PNAS written and peer reviewed by experts with over 200 years of experience designing reactors.

4) There are many elements that are in short supply besides beryllium. Helium and uranium come to mind immediately. Your reference on uranium is incorrect. Abbott 2012 shows that the energy used to mine low grade ores is greater than the energy you get from the reactor.

5) You claim that when Lyman says "MSRs generally require on-site chemical plants" he means "all MSRs". Generally doesn't mean all. Generally means most of the time, not all. You are completely wrong.

It is impossible to have a rational discussion when you insist generally means all.

6) Nuscale accused Krall et al of having an error in their paper. That is a very serious claim in science. Nuscale was completely incorrect. Their error was massive. Their letter was not written in good faith. I note that the Nuscale letter would not have passed peer review.

TheRationalView at 12:34 PM on 14 June 2022

What role for small modular nuclear reactors in combating climate change?

nuclear waste is a non issue when compared to any other power source. Power density is orders of magnitude higher so the ecological footprint is much smaller.

Good rebuttal about SMR waste argument at 10:12

Fossil fuel burning creates climate change and aerosols

hydro creates mercury in the food chain

solar and wind have short lifetimes and their manufacturing stream has a significant chemical waste footprint.

nigelj at 08:28 AM on 14 June 2022

A durable U.S. climate strategy … or a house of cards?

"Stopping greenhouse gas pollution will require a complete transformation of the way the global community produces and uses energy. We cannot achieve that goal without sustained efforts on many fronts: technological, scientific, socioeconomic and political."

Correct, and that's the key problem, because it requires literally hundreds of simultaneous changes and solutions, and this appears to be more than humans and our institutions can cope with mentally. Otherwise we would have made much more progress by now.

Imagine if one technological thing could fix the whole climate problem, and I think people would support that even if it cost them significant money. Its a mentally digestable sort of thing and clear cut. But we don't have that, so we are struggling.

macquigg at 06:30 AM on 14 June 2022

What role for small modular nuclear reactors in combating climate change?

scaddenp, the battle against climate science deniers has been won, and SkS played a major role. Even the oil companies are now promoting wind and solar. The war against global warming is much bigger than that one battle. Climate scientists should play a major role, even if they don't understand the technical details of nuclear power. Very few of the critical issues require that level of understanding. e.g. a civil engineer building inspector could verify the safety of many of the new designs. SkS should expand its role in this debate.

scaddenp at 06:07 AM on 14 June 2022

What role for small modular nuclear reactors in combating climate change?

BraveNewClimate was blog that discussed nuclear issues and had that focus. It attracted people with the appropriate expertise which contributors did not have. Sks has been about refuting denier arguments with published science. Arguments about nuclear energy potential seldom focus on any published science so it would be hard to see how Sks could work in that space effectively. Moderation is rather informal - moderators are people who read Sks and skim the new comments. If you arent interested in the nuclear debate, then probably skimmed too quickly for effective moderation.

Eclectic at 04:25 AM on 14 June 2022

UAH atmospheric temperatures prove climate models and/or surface temperature data sets are wrong

Knaugle , this very issue is addressed by the science journalist "Potholer54" in his latest Youtube climate video. Video dated 19 March 2022, and titled "A close look at Roy Spencer's claims on global warming". (Duration 20 minutes ~ and is number 59 in his climate series.)

The video lacks the usual humorous touch by Potholer54 . . . possibly because it leans more towards discussing Spencer's intransigence - the failure to acknowledge the validity of the mainstream climate science (owing to Spencer's religious fundamentalist belief that the Earth's climate is ultimately under divine control).

One Planet Only Forever at 04:15 AM on 14 June 2022

Planetary Diets

This is a good analogy for part of the fuller more complex issue of climate science. But it is missing some important aspects of the increased awareness and understanding of what is happening and the required changes and adaptations.

It has taken some time to reduce this to the following comment on this post. I intend to provide related ‘complementary or convergent’ comments on the Planetary Dieticians post and the “Cost increase in the electricity supply to achieve carbon neutrality in China.” item that is the lead in to the Skeptical Science New Research for Week #23 2022

A important awareness/understanding to be included is that the harmful climate impact problem is the result of the collective of personal actions. Everybody’s actions add up to be the future, and invariably impact Others. Climate science understanding is that the consequences of the climate change impact actions, the benefits and harms, are unfairly experienced. The ones who benefit most from the harm done generally will not suffer a commensurate amount (most) of the harm. What is happening is a reality that is a nasty version of the Corsican Brothers fictional tale. The Brother enjoying something feels little harm. Significant harm and little of the enjoyment is experienced by the Other Brother. It is also important to understand that those suffering climate impact harm include all the people of the future who have no influence today (which is a major part of the reason that the problem has not been seriously addressed in societies governed by current perceptions of popularity and status). That is a very important difference from presenting the case that an individual, or group, is only harming themselves by their actions.

A less significant point to include is that the type of donut consumed can also be understood to make a difference. But changing to lower calorie types only reduces the rate of the problem. Ending the donut eating is what is required along with actions by the donut eater to undo the damage done by the donut consumption.

That understanding connects to the unhelpful and harmful, but valid, claims that people will only change what they do after what they have developed a liking for is able to be replaced by something they see as being as enjoyable, cheaper and easier. Many people have learned things like ‘not to drive dangerously’ or ‘not to hit Other people’ or ‘not to litter’ without the development of an equally enjoyable alternative that was cheaper or easier (and some people did not even require the threat of penalties to learn to be less harmful and more helpful).

A serious problem is the people who resist learning from the advice of experts -> related comment in Planetary Dieticians.

knaugle at 00:54 AM on 14 June 2022

UAH atmospheric temperatures prove climate models and/or surface temperature data sets are wrong

Sorry, a bit more. I agree GISS and Berkeley show higher warming, but the delta is about half large as what UAH 6.0 shows. I guess it depends what one would call "reasonable".

Regardless, this page is very dated, ending at ver. 5.2.

knaugle at 00:50 AM on 14 June 2022

UAH atmospheric temperatures prove climate models and/or surface temperature data sets are wrong

MA Rodger @3

What I have to go on was David Cowtan's Univ. York Temperature plotter. For 2000 to 2018, UAH 5.6 reported warming of +0.193°C/decade.
Global set HadCRUT4krigv2 had +0.191°C/decade. That seems reasonably close to me. I have not seen what HadCRUT5 says.

Meanwhile UAH 6.0 gives +0.141°C/decade since 2000. That seems a big downward drop. I imagine different time frames could vary the comparison, but when I used WoodForTrees to plot them all in 20,30, & 40 year increments, UAH 6.0 always stands out. 5.6 not so much.

Cowtan's Univ. of York Temperature Plotter

macquigg at 21:01 PM on 13 June 2022

What role for small modular nuclear reactors in combating climate change?

Moderator @25, Thank you for you helpful comments. I apologize to anyone on this forum who may have mistaken my statements intended as constructive criticism of the forum, to be a disingenuous swipe at anyone here. I repeated some phrases I have heard from nuclear experts who could make a valuable contribution to this forum, but decline because they see too much personal bickering. In future comments, I will avoid criticism of this forum or any debate with other members, and stick to my original purpose, which was to collect the best critiques I can find for some Citizendium articles on nuclear power. Michael’s comments have been very helpful. I will pass the substantive parts on to the engineers who designed these reactors and get their response. Please think of me as a neutral editor at Citizendium, not a pro-nuclear partisan. If I am pro-anything, it is pro-science.

I understand the specialty at SkS is climate, not nuclear engineering. My suggestion was to encourage nuclear engineers to join and contribute. You have won the battle with climate science deniers. The big question now is how to solve the CO2 problem - renewables, nuclear, or both. I would love to see SkS play the same role in resolving this question as you played in resolving the climate debate.

I have read some of the comments on your earlier nuclear energy post, the first hundred two year sago, the last dozen or so just now. I am seeing the same problem with too much personal animosity. This will discourage experts from participating. You might want to take a look at the FaceBook forum Renewable vs. Nuclear Debate for an example of excellent moderation. OK, no more criticism after this. It’s your forum.

macquigg at 12:03 PM on 13 June 2022

What role for small modular nuclear reactors in combating climate change?

I will also be more careful about links. Please delete # 26,27,28 and this post. There doesn't seem to be any private message feature like in FaceBook forums.

macquigg at 12:01 PM on 13 June 2022

What role for small modular nuclear reactors in combating climate change?

Sorry for the duplicate posts. I have had several interruptions today, and apparently closing my laptop causes the unfinished comment to post. I wish there was a way to delete or edit a just-posted comment, but I will be much more careful in the future.

macquigg at 10:52 AM on 13 June 2022

What role for small modular nuclear reactors in combating climate change?

Michael Sweet @21: I will respond to your issues one at a time when I have some good information, so this may take a while. To keep track of where we are, I will continue the previous numbering, adding two more issues.

2) Non-fuel waste. I have a call in to an engineer who has had hands-on experience decommissioning reactors. What I am hearing from reactor designers is that irradiated steel is a trivial problem compared to the much more radioactive spent fuel.

5) Lyman's statement about all MSRs requiring on-site processing. See below.

6) The NuScale controversy. Looks to me like a miscommunication over an issue that doesn't really matter. They are arguing about maybe a factor of two at most in a volume of waste that is easily managed.

7) Cs-137. I have included your critique on the Discussion page for the ThorCon reactor. Watch this space. https://citizendium.org/wiki/Talk:ThorCon_nuclear_reactor#Radioactive_gases

========

Here is one issue I think we can be done with:

5) Lyman’s claim that all MSRs require on-site chemical processing.
Here is a fresh cut-and-paste from the Executive Summary of Lyman’s 2021 paper:
“All MSRs chemically treat the fuel to varying extents while the reactor operates to remove radio-active isotopes that affect reactor performance. Therefore, unlike other reactors, MSRs generally require on-site chemical plants to process their fuel.”
This statement is contradicted on page 102 with the statement “Some MSR concepts, such as ThorCon, would not have on-site reprocessing, but the company assumes that spent fuel salt would be sent off-site for reprocessing to recover unused fuel.”
The point of this statement about on-site processing is to emphasize the risk of diversion of fissile materials from operating reactors. Reprocessing at a secure central location does not have this risk.
It looks to me that Citizendium's handling of this controversy is correct. Most readers of Lyman’s paper will not get as far as page 102. They will be left with an incorrect understanding of MSR proliferation risk.
https://citizendium.org/wiki/Talk:ThorCon_nuclear_reactor#Risk_of_proliferation

======

I am having difficulty getting nuclear engineers to participate in this forum. One of them said he doesn't engage with belligerent sophomores. Another says they just ignore the greenies, they have no influence in the countries they are dealing with. If you want this forum to continue its excellent tradition of good science above politics, please stop accusing nuclear engineers of hiding problems. Assume that everyone is acting in good faith. Let's focus on the message, not the messenger. Peer review is a plus, but honest mistakes are possible.

macquigg at 09:49 AM on 13 June 2022

What role for small modular nuclear reactors in combating climate change?

5) Lyman's statement about all MSRs requiring on-site processing. See below.

7) Cs-137. I have included your critique on the Discussion page for the ThorCon reactor. Watch this space. https://citizendium.org/wiki/Talk:ThorCon_nuclear_reactor#Radioactive_gases

========

Here is one issue I think we can be done with:

======

Moderator Response:

[BL] Contents of duplicate post deleted. I assume that you did this by accident.

macquigg at 06:14 AM on 13 June 2022

What role for small modular nuclear reactors in combating climate change?

5) Lyman's statement about all MSRs requiring on-site processing. See below.

7) Cs-137. I have included your critique on the Discussion page for the ThorCon reactor. Watch this space. [Link]

========

Here is one issue I think we can be done with:

======

Moderator Response:

[BL] Links activated.

The web software here does not automatically create links. You can do this when posting a comment by selecting the "insert" tab, selecting the text you want to use for the link, and clicking on the icon that looks like a chain link. Add the URL in the dialog box.

Also note that the specialty here at SkS is climate - and more specifically rebutting false claims about climate science. We have several people well-versed in climate science, but we do not generally have access to many people with backgrounds in nuclear power engineering. Your expectations of SkS expertise (an all-volunteer group) need to be kept reasonable

To get an idea of the history of nuclear energy discussions at SkS, you can look at this post. This is not intended to cast aspersions on you, but to help you understand the path that nuclear "debate" has often taken, and why SkS regulars may respond the way they do. (The post is short; much of the history knowledge comes from reading the comments.)

https://skepticalscience.com/NuclearEnergy.html

Assuming that everyone is acting in good faith must a struggle when you find it difficult to get nuclear engineers to participate in your forum and they use phrases such as "belligerent sophomores" and "ignore the greenies", n'est pas?

Eclectic at 04:14 AM on 13 June 2022

What role for small modular nuclear reactors in combating climate change?

Michael, thank you. As I feared, using argon as an SMR coolant is quite impractical, owing to the neutron-damping property of argon's large nucleus. And using high-pressure CO2 limits the operating temperature range of an SMR (and I gather hot elemental carbon gas would degrade an SMR's structural materials). So, a shortened life for an SMR.

A dilemma. Helium is "mined" from a finite reservoir of subterranean gas ~ with a supply from USA of about 40m cubic meters of gas, and a similar amount from Russian wells (at time of writing, a daunting political problem). And a daunting political problem, to divert helium supplies away from usage by hospitals' Magnetic Resonance Imagers & the various other liquid-helium usages for cooling superconductors (unless someone invents the long-sought high-temperature superconductors).

Back-of-envelope :- Present world energy usage about 180,000 TWh annually. Roughly equivalent to 20,000 GigaWatts continuous, of which 15% is presently electrical generation (mostly with fossil fuels).

For full electrification by year 2050 : say 30,000 GW generation, requiring 300,000 of the above-mentioned "demonstration" Chinese SMR's of 100 MW generation each.

Obviously we would struggle to produce 10,000 Chinese SMR's annually for the next 30 years, quite apart from the helium deficiency. The nett-zero-carbon electric generation target would blow out past 2060 and 2070 . . . and beyond. Even allowing these my wild guesstimates to be discounted by 75% of the total generation that may come from wind & solar generation. (And maybe some biomass-derived fuels.)

An uncomfortable situation, dollar costings aside. Ignoring the helium question, it would seem that the future role of SMR's is likely to be tiny.

michael sweet at 00:47 AM on 13 June 2022

What role for small modular nuclear reactors in combating climate change?

Eclectic:

I found this:

"Helium is an inert and transparent gas that eliminates most of the problems associated with the interaction of the refrigerant with the structural materials. In addition, it has no moderating effect on fast neutrons, which makes the GFR neutron spectrum the most resistant among fast reactors," source (there are several articles at this cite).

The gas must be non-corrosive, stable at very high temperatures and low neutron cross section. Carbon dioxide is also used but it is very high pressure (about 200 atmospheres versus 70 atmospheres for Helium) and decomposes over 700 C.

Gas cooled reactors are designed to breed more fissile material. Since enough uranium does not exist to fuel large numbers of once through reactors, breeder reactors are designed to produce more fissile material. There are many technical and proliferation problems with breeder reactors.

In general, reactor designers are limited in the materials that have the exotic properties needed in the reactors. Rare and costly materials are widely used in nuclear reactors. That is why I try to always put "the materials to build the reactors do not exist" at the end of all my posts on nuclear reactors.

Nuclear power is uneconomic and the materials to build the reactors do not exist.

Eclectic at 14:10 PM on 12 June 2022

What role for small modular nuclear reactors in combating climate change?

Michael Sweet and Macquigg :-

if you have time, please briefly educate me on the SMR choice of helium as a cooling medium. Helium is expensive and finite in supply. And so there must presumably be a good technical reason for its choice (as opposed to using the cheap and abundant noble gas Argon).

Is it that the large size of the argon nucleus absorbs too much of the fissionable fuel's neutron flux, and thus reduces the SMR's fuel efficiency? Or does the neutron flux convert the argon into undesirable radioactive potassium . . . or cause the argon to fission into other undesirable elements? Or some other reason exists?

(The mandatory 3-minute googling has failed me ! )

michael sweet at 08:19 AM on 12 June 2022

What role for small modular nuclear reactors in combating climate change?

Macquigg:

Krall et al have responded to NuScales' letter (at the end of the article). It appears that NuScales' letter is completely without merit. I guess the reviewers at PNAS know more about nuclear reactor analysis than Nuscale does. I am not surprised.

You state somewhere that you want to post "what scientists think" and not nuclear propaganda. It seems to me that you consider anything that shows nuclear weaknesses to be propaganda and accept false claims from industry as what scientists think.

I do not have time to respond on other forums to baseless complaints that scientists are biased against nuclear power.

"What scientists think" is documented in the peer reviewed literature. If you want to discuss nuclear rationally you need to consider and post what the peer reviewed literature says. Krall et al 2022 is state of the art scientific thought.

Lyman 2021 is a 135 page, very well referenced report that summarizes what many scientists think about small modular reactors. It is grim reading. I suggest that you read it entirely, as I did, so that you know more about what you hope to moderate. At least it should be linked prominently on your pages.

On page 96 Lyman discusses MSR's that do not require reprocessing. On page 97 he discusses the Thor Con MSR reactor which also does not require reprocessing. Anyone who discredits Lyman with claims Lyman says MSR's require reprocessing is wrong.

On page 91 Lyman discusses the accumulation of ¹³⁷Cs in the noble gas stream of molten salt reactors. Cite his discussion on your pages. Lyman claims that there is too much radioactive noble gas to trap and store it as Thor Con claims they will do. I will have to see peer reviewed calculations (the NRC is ok) that show it is possible to trap all the noble gasses before I will believe Thor Con. I note that Thor Con keeps this data secret and refuses to say what they will do with the ¹³⁷Cs that will accumulate in the noble gas waste stream.

Abbott 2012 should be prominently discussed on your pages. People who discount Abbott using claims that hafnium is not used in commerical reactors are wrong.

Good luck in your efforts.

There is not enough uranium (and other rare elements) to build out a significant amount of nuclear power and the reactors are too expensive. I note Eclectic's concern about helium.

Eclectic at 01:19 AM on 12 June 2022

What role for small modular nuclear reactors in combating climate change?

Macquigg @ 19 , thank you also for the info on those Chinese demonstration SMR's coming online later this year (2022). A pair of SMR's of (electrical generation) approx 100 MW output each. Not quite sure whether I would class them as Small MR or Medium MR size.

I kind of take back my "Vaporware" comment ~ if I had written more slowly & thoughtfully, perhaps I might have found a more precise term. Still, we must await the case when SMR/MMR's are coming off the production lines and are "hitting the streets" in the necessary large numbers, and at a commercially viable cost. Remembering that the world's present electrical generation is roughly 3,000,000 MegaWatts and will need to increase about eight-fold by year 2050. (Would a quarter of that have to be from SMR's ?)

The Chinese reactors are described as using helium. So they are not quite the low-tech / low material cost type that I was expecting. Helium availablity & cost could be a big problem.

macquigg at 00:35 AM on 12 June 2022

What role for small modular nuclear reactors in combating climate change?

Eclectic, I'm still waiting for a response from ThorCon on Michael's questions, and I will hold off until I get more substantive answers. Meanwhile, we can discuss the timetable for SMRs. They are definitely not vaporware. China has one already on their grid. powermag.com/china-starts-up-first-fourth-generation-nuclear-reactor/

My understanding of the urgency of global warming and the status of the nuclear and renewable rollout is that both can now proceed at full speed while we wait for a solution to the storage problem for wind and solar and for the finishing touches on advanced reactor designs. The limit now is economic - how quickly can the world build more of each to upgrade the fossil fuel plants we have now. China is taking the lead, and will probably dominate this multi-trillion dollar market. The USA, Germany, Australia and a few others will lag behind due to intense anti-nuclear sentiment in those countries, but the impact on progress against global warming will be small, because the demand for zero-carbon power will stay ahead of supply for many years. If you are worried about production rate on existing SMR designs, take a look at ThorCon's plans. "The scale up rate will not be limited by shipyard capacity, but by the rate at which the turbogenerators can be built."

Eclectic at 20:40 PM on 11 June 2022

What role for small modular nuclear reactors in combating climate change?

Macquigg @17 , thank you for your "groups.google" link. It was rather a short discussion between you and your antagonist, in 2017. Your antagonist was severely irrational & ill-informed, and showed a stiff-necked hubris, typical of the crackpot type of science denier. But at least it all had a modicum of politeness ! And I must add that your antagonist produced nothing of value for the exceedingly erudite and rational readers here at SkS. ;-)

Returning on-topic . . . it seems to me that it is rather too early to spend much time debating the usefulness of Small Modular Reactors. At present they are Vaporware. Perhaps in a decade there might be a small number up-and-running ~ but there are many impediments to their becoming available in sufficient numbers to make a timely difference to the global warming problem of this century.

macquigg at 14:36 PM on 10 June 2022

What role for small modular nuclear reactors in combating climate change?

Michael Sweet,

My time is limited and I share your desire to avoid unproductive debate. I am an editor working with two warring camps, looking to find the best obtainable version of the truth. I am not a nuclear engineer, but I do have a lifetime of experience working against junk science in industry, academia, in Federal court, and in politics. I have even used this site as a resource in a debate with a sophisticated climate science denier
groups.google.com/g/az-2-forum Everyone could see he had lost the debate when all he could do is call the basic science on this site “propaganda”. Let’s not call these nuclear engineers liars, but instead focus on the issues and get to the facts.

I’m still working on point number 2, waiting for a response from an expert who has actual experience working with irradiated steel from nuclear reactors. I will then add that to our Q&A on non-fuel waste.

I have added your comments on Cs-137 to the section on Radioactive Gases and on Beryllium to the section on LImited Material Resources. Let me know if you want to change the wording and avoid any ambiguity. We are trying to distill the best possible pro and con statements on each issue from all the blather on the Internet.

Moderator Response:

[BL] Thank you for sticking to the issues.

michael sweet at 05:24 AM on 10 June 2022

What role for small modular nuclear reactors in combating climate change?

Macquigg,

In general, nuclear discussions on the web often degrade into repetitive posts with no conclusion. It seems to me that this discussion has reached that point. The comments policy of SkS is to refrain from repeating yourself once you have made your point. I will address your numbered points above.

1) As I have described in post 14 above, you are mistaken about what the abstract of Krall et al 2022 says. Please reread post 14. Krall et al say that the total radioactive waste from modular reactors is greater than current reactors, not the fission products only, like Thor Con claim.

2) Krall et al 2022 tell us that the issue of non fuel waste is a big problem. They also tell us that the developers have hidden this problem from public view.

In order to address this problem the developers of the reactors must release a complete analysis of their nuclear waste production including a complete discription of how they did the calculation. A new press release or email to the internet is not satisfactory. Why would a press release mean anything when we already know that they have hidden this problem from us for years?

3) Nuclear developers have lied about costs since 1950. Why would you think that I will believe them now? Why are you so trusting of people who have lied to us for your entire life and more? The reactors currently being built in Georgia were projected to cost $14 billion. They are now projected to cost $34 billlion and customers have paid additional billions of interest. Tell me more about cheap nuclear reactors. I note that 15 years ago all the small modular reactor developers said they would have designs by 2020, where are those plans?

4) Reactor developers must provide tabulations of all rare materials used in their construction. This data is currently kept secret. I noticed the beryllium issue.

Apparently nuclear supporters on the internet say hafnium is not used in current reactors and discredit Abbott 2012 because of this issue. The nuclear supporters are wrong here, not the peer reviewers of Abbott 2012. Hafnium is used in the control rods of most or all current reactors.

Nuclear supporters have not accurately quantified the amounts of rare materials used in reactor construction so it is not possible to determine which materials will be the first to run out. Supporters of renewable energy proved that the materials to build out an entirely renewable system exist after nuclear supporters claimed the materials did not exist. Nuclear supporters cannot prove the materials exist since nuclear developers keep secret the materials they use. Your claim that hundreds of years of uranium exist (on another site) is incorrect, read Abbott 2012 again until you understand the issue.

Criticizing peer review makes you look very bad on a scientific site like Skeptical Science. Especially since I have shown you to be incorrect on your issues where you criticized peer review. I suggest that you stop with this argument since it makes you look like you don't know what you are talking about.

5) Lyman only says reprocessing is required if the reactors want to reach the fuel efficiency that they claim. You are wrong. Since Lyman is a white paper it was not formally peer reviewed, although I am sure it was informally reviewed. When you critize peer review you look like you do not know what you are talking about.

If you want to claim that Lyman says all MSR's require reprocessing state the page number where the claim is made. I reread the entire section on MSR's and did not see the claim you suggest.

In post 8 you say you do not understand neutron leakage. That means that you do not know much about nuclear reactor design. Then you criticize peer review by people who have devoted their entire lives to reactor design. Does that really make sense?

Moderator Response:

[BL] Please try to tone it down a bit.

One Planet Only Forever at 10:59 AM on 9 June 2022

Grim 2022 drought outlook for Western US offers warnings for the future as climate change brings a hotter, thirstier atmosphere

Thanks for re-posting this article.

I have read several articles about this. But this article includes details that were not in the other articles, particularly the presentation of the anomaly of evapotranspiration over the past 40 years.

I have, however, noticed that the scale of the anomaly did not get copied across in the repost. In the original article the scale shows that the lows of 1980's was 4 inches less than the 60.5 inch average. And the high recent values were about 5 inches above the average.

macquigg at 03:52 AM on 9 June 2022

What role for small modular nuclear reactors in combating climate change?

Michael Sweet, thank you for your detailed response. I understand your reluctance to debate "the entire Internet", and I am OK working with you in this forum. I will even put up with your personal attacks, if there is enough substance to your criticism to make it worth my time. Your comment above is a mixed bag, but allow me to deal with one issue at a time, and we can come back to the others later.

1) On the issue of fuel waste, we seem to be in agreement that all reactors have the same amount of fission products generated per unit of thermal energy. That seemed to me the main criticism, which I quoted from the abstract of the paper. Unless I got this wrong, let's move on to the next issue.

2) On the issue of non-fuel waste, I've spent several hours trying to get a clear concise answer to the general question, and what we have is too much generality, not addressing the question head-on for this particular reactor. I will relay your comments above to ThorCon, and to others on Quora.com, where I got the other answers I posted. I will ask ThorCon specifically - What happens to the "343 tonnes of irradiated steel (one of the 4 "cans") shipped out for refurbishment" stated in their article under the heading "Average per year for a 500 MW plant:" I don't think they are being evasive. More likely, they just didn't see it as a big problem.

3) On the issue of cost, again I think this issue can be left for buyers and sellers to resolve. If ThorCon says they can deliver a complete plant at $1200 per kW, don't argue with them. Place an order. Don't talk about the cost of old PWR designs, and don't assume that other countries will have the same regulatory burdens as the USA. Don't compare costs to wind and solar without storage.

4) On the issue of materials resources, specifically beryllium, I will ask ThorCon. I did read a discussion on this forum about a point in Abbott 2012, on the supply of hafnium. Most reactors, even the old PWRs don't need hafnium. That should have been caught by the reviewers of Abbott's paper.

5) On Lyman's major point that all MSRs require online processing (thereby posing a proliferation risk) what happened here? Either the MSR designers have made a major error, or Lyman's paper is another example of failed peer review. Elysium says their FNR can go 40 years without reprocessing (fast neutrons are amazing).

Skeptical Science has been an excellent forum on climate change, the best in my opinion. I hope it will be the same on nuclear energy. Put aside politics. Get to the facts.

Moderator Response:

[DB] Please refrain from personalizing things and from false claims of ad hominems. The moderators review every comment here, perhaps not always in real-time, but inexorably, like gravity.

One Planet Only Forever at 03:08 AM on 9 June 2022

Driving with electricity is much cheaper than with gasoline

My comment at 5 only compares the energy efficiency of vehicles. The NRC search tool value of Le (Litres equivalent for electricity to be compared to gasoline) is simply based on the energy in 1 litre of gasoline being equivalent to the energy in 8.9 kWh of electricity.

But there is more to be aware of when evaluating electric vs. fossil fuel powered vehicles. The CO2 emissions from gasoline are about 2.3 kg per litre (many sources present that value). And, based on the EIA answer to "How much carbon dioxide is produced per kilowatthour of U.S. electricity generation?" (other sources present similar numbers):

CO2 emissions from coal generation of electricity, without verified carbon capture and permanent locking away, is about 1 kg per kWh. That means coal based electricity without CCS produces 8.9 kg of CO2 for a Le of electricity (8.9 kWh).
CO2 emissions from natural gas generation of electricity without CCS is about 3.6 kg per 8.9 kWh. That is better than coal but still significant.

The emissions from an electric vehicle with efficiency of 2 Le/100 km powered by coal electricity without CCS would be 17.8 kg / 100 km. That compares unfavorably to a hybrid having an efficiency of 5 L/ 100 km which would produce 11.5 kg / 100 km.

The Statista "Greenhouse gas emissions generation intensity in Canada as of 2015, by province" shows a wide range of emissions from electricity generation in Canada in 2015. In 2015 the average in Cnada was 0.14 kg per kWh. But the highest level of emissions per kWh was Alberta at 0.79 kg per kWh. The emissions from an electric vehicle with efficiency of 2 Le/100 km using 2015 Alberta electricity generation would have been about 13.4 kg / 100 km. That compares unfavorably to a hybrid having an efficiency of 5 L/ 100 km which would produce 11.5 kg / 100 km.

All regions in Canada have reduced their emissions since 2015. In 2019 the Alberta emissions were down to 0.62 kg per kWh. That would be 11.0 kg /100 for an electric vehicle with an Le of 2 L / 100 km. That is slightly better than a hybrid with 5 l/100 km. But it is not as good as a hybrid with 4 l/100 km.

A final note is that paying a premium to 'get low emissions electricity' to power up an electric vehicle does not magically create additional low emissions electricity generation in a region. The region's electricity generation mix remains what it is, with the person trying to be less harmful paying a premium that most likely does not reduce the harm done by regional electricity generation.

michael sweet at 02:02 AM on 9 June 2022

What role for small modular nuclear reactors in combating climate change?

Macquigg,

I applied to Citizendium but they have not sent me anything after a week. On mature reflection, I do not have time to explain reactor safety to the entire internet. I try to respond to people who post obviously false information on this website.

I have already stated above that Thor Cons' response to radioactivity in the paper is deliberately false. Obviously you do not understand the facts of the case.

In the abstarct of Krall et al 2022 it says:

""the intrinsically higher neutron leakage associated with SMRs suggests that most designs are inferior to LWRs with respect to the generation, management, and final disposal of key radionuclides in nuclear waste." (my bold)

This means all the radionuclides in the reactor i.e. the fission products and the reactor components rendered radioactive by neutron bombardment from high neutron leakage. The paper states clearly that reactor developers have not reported the amount of reactor components that become radioactive. The paper then claims that the reactor components are a major part of the waste chain and must be calculated. Obviously all radioactive waste has to be disposed of.

This calculation should have been done by reactor designers but they have been negligent and not provided this data. Why have the designers hidden this damaging information?

According to you, Thor Cons' response is "All fission reactors produce essentially the same amount of fission products" (my bold). Thor Con deliberately ignors the entire point of the PNAS paper. The extra waste is the irradiated steel and other reactor components. Where I was raised that is deliberate falsifacation. It is not my problem that you do not understand the quotes you post.

In your discussion on Citizendum poster Lyle Elhaney posts a long comment claiming that iron does not become radioactive under neutron bombardment. He concludes:

"Other materials - some do become radioactive when drenched with neutrons for an extended time. One would need to know what materials to analyze what happens."

Krall et al 2022 now tell us. The other materials cause a great deal of problems. For one example, ⁵⁸Ni is present in large amounts in the 316 steel and is converted into radioactive ⁵⁹Ni. There are other problematic isotopes formed. Analyizing the iron alone deliberately minimizes the problem. The comment should be updated to reflect that peer reviewed scientists think this is a big problem.

Roger Bloomquist states:

"There are small concentrations of activated structural elements like cobalt. These typically have half-lives of years, not multiple decades"

The ⁵⁹Ni mentioned above as one of the major isotopes formed in the irradiated 316 steel has a half life of 72,000 years. Since it will have to be isolated for over 10 half lifes to decay that is over a million years. Where I live that is way more than "years". Bloomquists post is false and should be deleted. A new post stating that the radioactive steel will have to be stored for over a million years should be put in its place.

Nuclear designers have been claiming since 1950 that nuclear power will be cheap and safe. They have failed to produce on their promises. You are obviously new to this conversation. I suggest that you carefully read Abbott 2012 (referenced on citizendium) which gives 15 reasons why nuclear power can never produce more than 5% of all power and Lyman 2021 "Advanced" isn't always better (white paper from the Union of Concerned Scientists). I spent two weeks reading Lyman and several hours reviewing it for these posts so I am unsympathetic to your using an hour reading Krall et al. 2022.

Neither you nor Thor Con has addressed my point that there is not enough beryllium to build out more than a few Thor Con reactors. I would like to see how they calculate that a disposable reactor that only lasts 4 years can compete on price with a wind generator or solar farm. I note that they claim only that they can produce electricity as cheaply as coal while wind and solar today are cheaper than coal.

Nuclear power is uneconomic and the materials to build the reactors do not exist.

peppers at 01:54 AM on 9 June 2022

Pollution's Staggering Death-toll

Climate change is about the planets temp. rise, and pollution is only vaguely related. Not less important.

J4zonian at 22:35 PM on 8 June 2022

Planetary Dieticians

Great analogy, well presented.

The footnote/moral makes it sound like Bob can eat as many donuts as he wants without hurting his health, as long as he exercises enough. He can't.

IOW, offsets aren't the same as emission reductions. If Bob weighs 280 and is still gaining weight, it's time for him to stop eating donuts, eat only as much of everything as he needs, with a healthy mix of nutrients, and still exercise enough to lose weight.

The world has to stop emitting carbon now. It has to stop burning fossil fuels and replace them with efficiency, wiser lives, and clean safe cheap renewable energy as fast as humanly possible. It needs to replace chemical-industrial agriculture with small-scale low-meat organic permaculture; transform industry to ecological forms. No amount of offsets can make up for not doing all of that now, but we need to offset massive amounts of carbon by planting and nurturing forests, undisturbed wild grasslands, and mangroves.

macquigg at 14:30 PM on 8 June 2022

What role for small modular nuclear reactors in combating climate change?

Michael Sweet, I understand that you are busy, and not enough time to thoroughly research these issues. Me too. I know that the "propagandists" who are designing the new reactors are even busier than us, and I don't want to bother them with this debate.

Let me suggest that we avoid a long debate with lots of ad hominem, argument from authority, etc., and just focus on a few of the most important questions. I will get expert responses to any issues you care to pursue. What I need from you is a short statement on each issue, exactly the way you want it to appear on one of our Discussion pages. I will give you the same control over your statement that the "propagandists" have on the content of the articles on their own reactors. You will also have the opportuntity to modify your statement after you see their response. We need a short point-counterpoint on any unresolved issues.

On the issue of increased nuclear waste from the ThorCon reactor, I understand you think the company's response is "deliberately evasive". It looks to me like they responded perfectly to the issue as stated. I quoted the criticism directly from the abstract of the Krall paper.

Perhaps you would like to restate the issue, emphasizing what you think they are evading. If you are worried about non-fuel waste, that is a separate question, already addressed on the Discussion page.

Moderator Response:

[DB] Hotlinked URL. Please learn to do this yourself.

michael sweet at 12:56 PM on 8 June 2022

What role for small modular nuclear reactors in combating climate change?

Macquigg,

I am too busy to write a full reply to your posts right now.

A paper printed in the PNAS has much more wieght than propaganda released by nuclear plant companies. Who cares what paid shills say compared to nuclear reactor designers with decades of experience.

The issue with Thor Cons whining is that the paper clearly says that one of the major problems with small reactors is the high neutron leakage. In post 8 you say you do not understand this problem and that it is endlessly discussed on facebook. We have an clear answer to the facebook arguments: scientists think neutron leakage is a major problem. The fact that you do not understand it does not mean that it is not a problem.

ThorCons answer that you quote is deliberately evasive. Yes, the amount of fission products is about the same. The high neutron leakage of their design results in the rest of the reactor becoming much more radioactive than happens in larger reactors wiith low neutron leakage. The final result is much more radioactive waste that has to be permanently disposed of. Thor Con ignores the claims made in the paper and argues using an answer that everyone who is informed already knows. The ThorCon argument has no merit.

Where I come from that is deliberate deception.

I note that no process exists to treat the leftover salt mix in the Thor Con reactor.

In addition, ThorCon has 12 mol% Beryllium in its salt mix. There is only one large Breyllium mine in the entire world. From ThorCons' numbers I calculate that a single 1,000 MW plant would use approximately 2.5 tons of Beryllium to start up. Since total world production of beryllium is about 260 tons/year and ThorCons have to be replaced every 4 years, 400 1,000 MW ThorCons (approximately current world nuclear reactors) would use up the entire world supply. You forgot to include in your summary that there are many elements that do not exist in sufficient supply to build out more than an insignificant amount of nuclear power. (always take calculations that have not been peer reviewed with a large grain of salt. You could do the calculation yourself to check my numbers, if you know how.)

ThorCons ¹³⁷Cs claims also do not stand up to scrutiny. Much ¹³⁷Cs is carried out of the salt in the noble gas stream. They have to say what they plan to do with the ¹³⁷Cs that is mixed with their radioactive noble gasses. If it remains in the salt they have to explain how that occurs.

I suggest that you find someone who understands nuclear reactor design to moderate your thread if you want to correctly deal with the nuclear industry propaganda.

If the bleeting from the nuclear designers has any merit they can write a letter to the editor of PNAS and it will be answered in time. Until their letter is published we have to figure that the paper is correct.

I note that the rest of the responses that you have linked did not address the issue of increased radioactive waste even though that was what the headline in the newspaper was.

It is difficult to discuss nuclear power on line since the proponents of nuclear consistently make false claims.

Nuclear power is too expensive and the elements to build out the reactors does not exist.

One Planet Only Forever at 10:50 AM on 8 June 2022

Driving with electricity is much cheaper than with gasoline

Doug, Bob and peppers,

Natural Resources Canada has developed a tool for searching and comparing the fuel efficiency of personal vehicles sold in Canada.

NRC Fuel consumption ratings search tool

Setting the search "vehicle type" to be "battery-electric" finds 81 vehicle models, including 4 pickup truck models showing the following comparisons:

The most efficient vehicles (3 of the 81 models) are 1.8 le/100 km. And they are sedan style vehicles. (le is litres equivalent - see Note at end of comment).
The next most efficient models (4 models) are 1.9 le/100 km including the most efficient SUVs.
The next set (9 models) are 2.0 le/100 km and includes several SUVs.
The most efficient battery-electric truck is 3.3 le/100 km which is better than the least efficient SUV (3.6 le/100 km). And it is slightly better than the least efficient sedan which is 3.4 le/100 km.

And setting the search to only be conventional (ICE)/hybrid vehicles finds that the most efficient hybrid is 4.0 l/100 km (not as good as the least efficient battery-electric)

Note: The search can be set for "miles/gallon". But there are 2 choices because the antiquated imperial system has 2 different gallon size: "imperial (the Canadian gallon before the switch to metric in 1979)" and "US (the smaller one the US created and still uses)".

Doug Bostrom at 08:33 AM on 8 June 2022

Driving with electricity is much cheaper than with gasoline

As a hint about voting w/wallets and heavier vehicles, Ford's "F-150 Lightning" (now being delivered into customer hands) has generated about 200,000 reservation orders, with Ford needing close to order availabilty and add manufacturing capacity. Ford is being forced to consider cutting dealers out of the equation on selling these vehicles, because dealers are successfully extracting absurd markups from customers willing to pay.

Granted, these are early adopters but it remains the case that such empirical evidence as we have suggests that the love affair for "heavy" doesn't axiomatically require that heavy vehicles be farting thrashers (IC powered).

Meanwhile, the same efficiency gains that make carrying a 900+ pound battery in a sedan a productive decision apply to heavier vehicles as well. The pertinent equation after all is not K.E. = 1/2 m² v²

MA Rodger at 04:41 AM on 8 June 2022

UAH atmospheric temperatures prove climate models and/or surface temperature data sets are wrong

knaugle @2,

I would not myself say that UAH TLTv5.6 "showed reasonably close agreement" with anything other than HadCRUT4 which itself showed less warming than other SAT records like GISTEMP.

And while RSS TLTv3.3 showed lower warming than all others back in the day, RSS TLTv4.0 is now showing more warming than UAHv5.6 did.

A comparison between HadCRUT4, UAH TLTv5.6 & v6.0 and RSS TLTv4.0 is plotted in this WoodForTrees presentation. Note how UAH v6.0 diverges over a short period 2000-12 which is symptomatic of a satellite calibration issue, something the UAH folk themselves accuse other satellite records of ignoring.

knaugle at 02:29 AM on 8 June 2022

UAH atmospheric temperatures prove climate models and/or surface temperature data sets are wrong

It would be interesting to see the corrections applied to subsequent versions. I know UAH 5.6 showed reasonably close agreement with the surface datasets (and with RSS TLT v. 4). Then it was replaced by UAH 6.0 and it immediately diverged to lower warming relative to all the other sets I follow.

macquigg at 00:50 AM on 8 June 2022

What role for small modular nuclear reactors in combating climate change?

From ThorCon:

"All fission reactors produce essentially the same amount of fission products per thermal energy produced. This is immutable physics. Designs with higher thermal efficiency produce less fission products per kWh electricity produced, but this difference is less than a factor of two from the clunkiest LWR to the fanciest paper HTGR."

I am not a nuclear engineer, and I did not spend more than an hour trying to understand Krall's article, but it seems like the whole thing fails on this one point. What is wrong with the peer review at NAS?

Bob Loblaw at 22:45 PM on 7 June 2022

Driving with electricity is much cheaper than with gasoline

peppers:

The blog post does address the issue of the recent spike in gas prices as a comparison. Note that it says (emphasis mine):

Clearly, making these comparisons using high gas prices will reflect a big savings for EVs. But you’d have to go back to 2002 to find a time when the price of gasoline was consistently below the $1.41 per gallon price of driving an EV.

As for heavier vehicles being inefficent: do you have a reference for that? In general, my understanding is that vehicles with electric drive are much more efficient that IC engines at low speeds, starting, etc. Electric motors can generate high torque at low speeds - a range where IC engines are very inefficient. For truck used for many short, local trips, the advantage of an electric drive could be substantial, even if range is limited. Long hauls, not so much.

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