NNadir
NNadir's JournalA Solar Thermochemical Water Splitting Paper with Surprising Honesty of "Solar Hydrogen" Efficiency.
Before I get started, let me state categorically that I oppose solar thermal plants, all of which have been environmental and economic failures, including the in flight bird fryer at Ivanpah in the Mohave Desert. (The Ivanpah plant is a disgrace.)
However, solar thermal papers are worth reading because they are readily adaptable for use in clean energy, clean energy being limited to nuclear energy.
I've been hearing about solar hydrogen my whole adult life, and I'm not young. Usually it involves bullshit about solar PV cells and electrolysis. After 40 or 50 years, I'm still hearing about it, even though as of 2022, better than 95% of the world's hydrogen is still produced by the reformation of dangerous natural gas, or worse, coal.
I came across this paper this evening which has some surprising honesty about the thermodynamic efficiency of solar PV "solar hydrogen" efficiency: Concentrated Solar Energy with Thermal Energy Storage for Hydrogen Production by Three-Step Thermochemical Water-Splitting Cycles (Alberto Boretti Energy & Fuels 2021 35 (13), 10832-10840)
The fun part:
The indirect approach may be attractive for the low cost of photovoltaic electricity, and the good development of electrolyzers. However, it suffers from two downfalls.
First, it does not make too much sense to transform an energy carrier, electricity, into another energy carrier, hydrogen, with an efficiency very far from unity, and eventually transform back to electricity in a fuel cell. Polymer electrolyte membrane (PEM) electrolyzers have efficiencies (hydrogen fuel energy vs electricity) of ?70%. (4) The conversion of hydrogen back into electricity in fuel cells occurs with another efficiency (electricity vs hydrogen energy) far from unity at about ?50%. (5) The round trip efficiency electric to hydrogen to electric is ?28%. Thus logically, electrolyzers and fuel cells do not compete with Li-ion batteries. It does not make sense to produce hydrogen from electricity, and then use fuel cells to produce electricity again by using hydrogen, as every energy conversion has a cost.
Second, photovoltaic solar panels (for example thin-film CdTe) have solar energy collection efficiencies of only 17%. The “First solar” CdTe solar panels are the most efficient solar panels on the market at 17% efficiency. (6) Much higher solar energy collection efficiencies are permitted by concentrators to thermal energy. In principle, novel beam-down concentrators such as the Ayman solar concentrator (ASC), (7) (8) have solar energy collection efficiencies above 90%, and more traditional concentrated solar power (CSP) solar tower designs still have solar energy collection efficiencies up to 60%. The traditional steam Rankine power cycle may then be used to produce electricity from the thermal energy collected by CSE with efficiencies above 40%. High temperature advanced ultrasupercritical (AUSC) steam Rankine cycles, or supercritical CO2 Brayton cycles, permit efficiencies above 50%. This means that 24 to 30% of the solar energy can be converted to electricity in a conventional solar tower CSP, and 36 to 45% in novel concentrators. CSP (with TES) has then the additional value of dispatchability. The best perspective for hydrogen production is through the catalytic thermochemical pathway, by using thermal energy without producing electricity. Hydrogen may be produced with thermochemical water splitting (TWS) cycles with available solar thermal energy almost five times the available energy of solar photovoltaic electricity.
I added the bold.
From my perspective it does not make sense to make hydrogen from any form of solar energy simply from a land use perspective. Oh, and about that "levelized cost of solar electricity," that's nonsense too. It refers to the cost of electricity when the sun is shining and accounts for neither the environmental nor the economic cost of the necessary redundant systems.
The thermal efficiencies discussed in this paper are nonetheless useful, since they transfer directly to cleaner and far more sustainable energy, nuclear energy.
Of the 5 Ph.D. programs in nuclear engineering to which my son applied, he has heard back from three, two consisting of faculty interviews and one, with no interview, accepting him, and the other four pending. He will thus be a nuclear engineer, and I shared this interesting paper with him given the interesting thermodynamic perspective.
It's 2022; I can't understand how anyone anywhere is publishing a paper like this one.
The paper in question:
High Selectivity CO2 Capture from Biogas by Hydration Separation Based on the Kinetic Difference in the Presence of 1,1-Dichloro-1-fluoroethane (Yanhong Wang, Jinfeng Lu, Jing Qi, Xuemei Lang, Shuanshi Fan, Chi Yu, and Gang Li Energy & Fuels 2021 35 (13), 10689-10702)
1,1-dichloro-1-fluoroethane is HCFC-141b. Under the Montreal protocol its (marginal) production was banned as of 2020.
There are a zillion ways to separate CO2 from biogas in which it's not involved, not that biogas amounts to much on the scale of energy use.
Closing the Phosphorus Cycle with Sewage Sludge, Wheat Straw, and Sunflower Husks (for example).
One of the very serious depletion issues before humanity that doesn't get much attention is that of phosphorus.
Before the so called "green revolution" involving screwing up land use on this planet for so called "renewable energy," there was a real "green revolution" involving increasing the productivity of agricultural land. This real "green revolution" involved, among other things, fertilizers, the two main components being fixed nitrogen (via the energy intensive Haber Bosch process) and the nonrenewable resource phosphorus.
I am always interested in the chemical composition of ash, particularly biomass ash, as a potential source of phosphorus, as a means of capturing it before it destroys bodies of water by inducing eutrophication.
I came across this cool paper in the literature this morning while catching up on my reading:
Single Pellet Combustion of Sewage Sludge and Agricultural Residues with a Focus on Phosphorus (Gustav Häggström, Thomas Karl Hannl, Ali Hedayati, Matthias Kuba, Nils Skoglund, and Marcus Öhman Energy & Fuels 2021 35 (12), 10009-10022)
From the paper's introduction:
Utilization of biomass can help decrease the dependence on fossil fuels for heat, power, and biofuel production. This aids in the mitigation of CO2 addition to the atmosphere and combats global warming, a contemporary topic for environmental research. Another topic is that of resources and efficient utilization of existing natural reserves, including recycling of materials essential for the human ecosystem. One element vital for global food production is phosphorus. (13) This essential element is currently mined and extracted from ore deposits for further processing into mineral fertilizers. As of 2020, the annual demand of P (in the form of P2O5) is about 63 million tons, mainly extracted from ore deposits. (14) Anthropogenic use of this P can lead to eutrophication of water systems in the vicinity of agricultural land. (15) A fraction of it ends up in waste streams such as sewer systems and is subsequently processed to digested sewage sludge (SS) in wastewater treatment plants (WWTP). In the European context, some of the P in SS is utilized for fertilization of agricultural land, but large proportions are still deposited as materials with no utilization of the inherent P content. (16)
There are several methods for P recovery from SS. These options can be divided into methods of treating the SS directly in the WWTP or post-treatment of the produced digested SS. (17) The most mature direct method is struvite precipitation, where the fraction of P dissolved in the water phase is precipitated as struvite inside the WWTP, (18) but this is not applicable for P bonded in solid particles since it only targets dissolved P. For post-treatment extraction, there are mainly the thermal conversion options of pyrolysis and subsequent collection of P-rich char (19) or mono-combustion with post-treatment of the ash. (20,21) These thermal conversion processes also present an opportunity to destroy possible organic pathogens and toxins within the SS (22) and separation of volatile heavy metals from coarse ash through fractionation. (22) However, mono-combustion of SS mainly forms phosphates with low availability to plants, such as apatite and Fe-whitlockites.
Struvite, for those who don't know, is a mixed magnesium/ammonium phosphate as a form in which phosphorus can be recovered as it is only sparingly soluble. (It is the mineral that forms in kidney stones, particularly kidney stones in dogs.)
I'm a pyrolysis kind of guy myself, since pyrolysis is amenable to the utilization of the only sustainable form of energy there really is, nuclear energy. This is a combustion paper, and I'm not necessarily opposed to combustion of biomass if and only if it is done cleanly, for example under oxyfuel conditions (whereby carbon can be recovered). In any case, the ash from pyrolysis and from combustion will have similar chemical compositions.
Thus, it is with interest that I came across this table in the paper:
Here SS refers to sewage sludge, WS to wheat straw, and SH to sunflower hulls. The latter two are for reference, other biomass types of agricultural wastes can be expected to be similar. The columns with numbers in them refer to percentages of sewage sludge in the respective mixtures in percentage terms.
There is a lot of discussion in this interesting paper, but I thought I'd just refer to a paragraph in the conclusion which follows:
This is important work, albeit out of sight and thus too often out of mind. The future of humanity depends on closing the phosphorus cycle.
I trust you are having a pleasant weekend. I have to start with some snow removal stuff myself, but it's invigorating to do so.
A Nazi's Son Serves in the Isreali Army.
This is quite a story, not about Nazis really, not about Israelis, but about being a human being:
Where did Omicron come from? Three key theories
This is a news story in the current issue of Nature:
Where did Omicron come from? Three key theories
Subtitle: The highly transmissible variant emerged with a host of unusual mutations. Now scientists are trying to work out how it evolved.
It is probably open sourced.
Some excerpts:
There’s no transparent path of transmission linking Omicron to its predecessors. Instead, the variant has an unusual array of mutations, which it evolved entirely outside the view of researchers. Omicron is so different from earlier variants, such as Alpha and Delta, that evolutionary virologists estimate its closest-known genetic ancestor probably dates back to more than a year ago, some time after mid-2020 (ref. 1). “It just came out of nowhere,” says Darren Martin, a computational biologist at the University of Cape Town, South Africa.
The question of Omicron’s origins is of more than academic importance. Working out under what conditions this highly transmissible variant arose might help scientists to understand the risk of new variants emerging, and suggest steps to minimize it, says Angela Rasmussen, a virologist at the University of Saskatchewan Vaccine and Infectious Disease Organization in Saskatoon, Canada. “It’s very difficult to try to mitigate a risk that you can’t even remotely wrap your head around,” she says...
...Researchers agree that Omicron is a recent arrival. It was first detected in South Africa and Botswana in early November 2021 (see ‘Omicron takeover’); retrospective testing has since found earlier samples from individuals in England on 1 and 3 November, and in South Africa, Nigeria and the United States on 2 November. An analysis of the mutation rate in hundreds of sequenced genomes, and of how quickly the virus had spread through populations by December, dates its emergence to not long before that — around the end of September or early October last year2...
... because Johannesburg is home to the largest airport on the African continent, the variant could have emerged anywhere in the world — merely being picked up in South Africa because of the country’s sophisticated genetic surveillance, says Tulio de Oliveira, a bioinformatician at the University of KwaZulu-Natal in Durban and at Stellenbosch University’s Centre for Epidemic Response and Innovation, who has led South Africa’s efforts to track viral variants, including Omicron...
Caption:
Researchers have explained the emergence of previous variants of concern through a simple process of gradual evolution. As SARS-CoV-2 replicates and transmits from person to person, random changes crop up in its RNA sequence, some of which persist. Scientists have observed that, in a given lineage, about one or two single-letter mutations a month make it into the general viral circulation — a mutation rate about half that of influenza. It is also possible for chunks of coronavirus genomes to shuffle and recombine wholesale, adds Kristian Andersen, an infectious-disease researcher at Scripps Research in La Jolla, California. And viruses can evolve faster when there is selection pressure, he says, because mutations are more likely to stick around if they give the virus an increased ability to propagate under certain environmental conditions...
... Chronic infection
An alternative incubator for fast-paced evolution is a person with a chronic infection. There, the virus can multiply for weeks or months, and different types of mutation can emerge to dodge the body’s immune system. Chronic infections give the virus “the opportunity to play cat and mouse with the immune system”, says Pond, who thinks it is a plausible hypothesis for Omicron’s emergence.
Such chronic infections have been observed in people with compromised immune systems who cannot easily get rid of SARS-CoV-2. For example, a December 2020 case report described a 45-year-old man with a persistent infection5. During almost five months in its host, SARS-CoV-2 accumulated close to a dozen amino-acid changes in its spike protein. Some researchers suggest Alpha emerged in someone with a chronic infection, because, like Omicron, it seems to have accumulated changes at an accelerated rate (see go.nature.com/3yj6kmh)...
... Mouse or rat
Omicron might not have emerged in a person at all. SARS-CoV-2 is a promiscuous virus: it has spread to a wild leopard, to hyenas and hippopotamuses at zoos, and into pet ferrets and hamsters. It has caused havoc in mink farms across Europe, and has infiltrated populations of white-tailed deer throughout North America. And Omicron might be able to enter a broader selection of animals. Cell-based studies have found that, unlike earlier variants, Omicron’s spike protein can bind to the ACE2 protein of turkeys, chickens and mice3,7.
One study found that the N501Y–Q498R combination of mutations allows variants to bind tightly to rat ACE2 (ref. 6). And Robert Garry, a virologist at Tulane University in New Orleans, Louisiana, notes that several other mutations in Omicron have been seen in SARS-CoV-2 viruses adapting to rodents in laboratory experiments.
The types of single-nucleotide substitution observed in Omicron’s genome also seem to reflect those typically observed when coronaviruses evolve in mice, and do not match as well with the switches that are observed in coronaviruses adapting to people, according to a study of 45 mutations in Omicron8...
I seem to have had this interesting variant; but as I was triply vaccinated, I'm pretty much over it.
Interesting read, I think.
Princy Mthombeni: Nuclear energy is critical to Africa's agenda for sustainable development.
Viewpoint: Nuclear energy is critical to Africa's agenda for sustainable developmentNuclear power can play a key part in addressing African energy poverty while mitigating against climate change and helping to solve the triple threats of poverty, inequality and unemployment, but policymakers, decision takers and the general public need to be educated on its benefits, says Princy Mthombeni.
Excerpt:
Clearly a light bulb does not constitute adequate access to energy when there are so many people that desperately need clean, affordable, reliable and equitable access to energy supply for clean water, public health and jobs. This energy crisis demands that Africa should take the opportunity to shape a better energy future for Africans. This in turn directs attention to the diversity of options emerging for progressing global net-zero carbon energy transition pathways that will benefit the most vulnerable people on the planet. Nuclear power, as a source of energy that is clean, reliable, dispatchable and baseload, is key in addressing the energy poverty on the African continent while mitigating against climate change issues...
...and so on...
The first daily reading above 420 ppm this year has appeared at the Mauna Loa CO2 observatory.
Here's the carbon dioxide readings from the last 5 days:
Mauna Loa Carbon Dioxide Observatory Accessed 1/27/2022.
January 26: 420.52 ppm
January 25: 419.19 ppm
January 24: 419.80 ppm
January 23: 418.96 ppm
January 22: 417.51 ppm
Last Updated: January 27, 2022
It's a little early in the year for the data to break the previous year's record. In weekly data, the time of year that the concentrations pass that of the previous year in a February time frame. For example, in 2021, the record data for 2020, 417.43 ppm recorded for the week beginning May 25, 2020, was not passed until the week of February 28, 2021, when it was 417.97 ppm, going on to rise to 420.01 ppm for the week beginning April 25, 2021.
The data above is daily data, and the weekly data will be an average of as many daily data points are available for the week. If the weekly average exceeds 420.01 ppm in early February, part of the reason may be involved with the European reliance on coal this week given surges in the prices of natural gas. (Recorded european carbon dioxide reductions in recent years are tightly involved with the substitution of Russian gas for coal; the wind blowing regularly also had some] effect, counterbalanced by the German decision to close nuclear plants.)
I have been checking in informally all week on the Electricity Map data for Germany at different points of the day an night. The German carbon intensity for electricity for the entire time, with no exceptions, has been in the high 400s g CO2/kwh to low 500s g CO2/kw, generally running 400% to 500% higher than the carbon intensity of heavily nuclearized France. (Four large French nuclear reactors are off line to replace borated water feed lines as a result of findings in a routine inspection. They are expected to come back on line on March 31.)
There is no joy in the Energiewende world today: The current German carbon dioxide intensity is now (01/27/2022, 12:50P EST (US)) is 475 g CO2/kwh, with coal producing 25.6 GW of electrical power, wind producing 6.20 GW of electricity - 9.68% capacity utilization - and solar producing 0.413 GW of electricity - 0.71% capacity utilization.
France is at 99 g CO2/kwh at this time.
It's not going to be pretty in the climate change data world in 2022. Look for bad times ahead.
I almost forgot: the first goal of the "renewable energy" fantasy was never about climate change.
It was always about replacing the best option to fight climate change (as well as other forms of immediately deadly air pollution), nuclear energy.
How I lost track of this I don't know, since I have been pronuclear after I fully understood Chernobyl, and certainly in my early tenure here and elsewhere in the blogging world, almost all of the wind and solar advocates were far more interested in attacking nuclear energy than fossil fuels, and in many cases still are.
Recently a correspondent here kindly directed my attention to a series of podcasts of which I was unaware, that brought home this point, one a discussion of the fool Amory Lovins, another a talk with a young German pronuclear activist who has an excellent command of the history of nuclear power in Germany, as well as the history of the so called "green" anti-nuclear establishment.
They are here:
A Hard Landing for Soft Energy ft. Mark Nelson
...and...
The Grim Fairy Tale of German Electricity feat. Noah Jakob Rettberg
To be sure, they were far kinder to Lovins than I would be. The point was that he elevated his (irrational) fear of all things nuclear over every other risk, including, but not limited to, climate change.
They referred to Lovins as the "Intellectual Godfather" of Energiewende, I disagree with the use of the word "intellectual" in this context, having read as much of Lovins writing as I could stomach. (To me, his writing has the feel of a ten grade term paper, to which - were I a high school teacher, I might grade with a B- or a C+, the minus for the lack of references, the + for stringing together a specious argument in a compelling way, albeit based on false premises.)
As for Energiewende, the most gripping part of Herr Rettberg's account is the depth and level of propaganda in Germany by his teachers, members of an establishment that was at one time the radical opposition when it came to all things nuclear. I was, of course, familiar with this kind of propaganda, having been an anti-nuke in my youth, and it was, in fact, the comparison between the propaganda I'd absorbed and the reality of Chernobyl that led me to change my mind and become pro-nuclear.
The point is only this: In the minds of these people nuclear energy is more dangerous than climate change. There is something almost Trumpian in the scale of this delusion, but in the age of the celebration of the lie, there's just no talking to these kinds of people.
As the events in Germany this week are showing, where coal is providing the largest share of German electricity, and where the carbon intensity of electricity has hovered between 475 g CO2/kwh and 525 g CO2/kwh, climate change takes a back burner to anti-nuke terror, no matter how many facts one presents on the respective relative risks.
Facts define reality, but many people push reality away, although it can only be pushed only so far before the price of the consequences must be paid.
The German carbon intensity this week may be compared to levels 90 g g CO2/kwh and 115 g CO2/kwh for nuclear heavy France this week, Germany's neighboring company. This is higher than the generally given figures for nuclear energy - the Electricity Map from where these numbers come - gives 11 g CO2/kwh for nuclear based on an IPCC report's calculation, other literature gives slightly higher or slightly lower carbon intensity for nuclear. The Electricity Map however, charges carbon intensity based on the carbon intensity of nations from which a nation imports. With 4 large reactors in France down until the end of March to replace some feed pipes that didn't pass routine inspection, France has occasionally been importing electricity from dirty Germany, as well as Spain, Belgium and the UK, soiling its electricity. Also, in France, there was some willingness to drink the Wind Energy Kool-Aid, hence France is burning gas for electricity this week.
I consider this a fact, and am not really open to "alternative facts:" If one fears nuclear above all else, one will be working to assure that the climate catastrophe now underway will accelerate without limit. If one, by contrast, thinks that climate change is more of a risk than the potential for radiation release, one will insist on nuclear energy.
Climate change will not be addressed without nuclear energy. This is a fact. Facts matter.
The problem that many people have with nuclear energy is simply this that they have been trained by our culture - the world culture actually - to believe that so called "renewable energy" is a positive good, even though this positive good existed and was practiced by humanity and was largely abandoned by humanity in the 19th and early 20th century for a reason. (Some people never abandoned it; we generally consider the bulk of these people "impoverished." ) Therefore, the cultural definition of so called "renewable energy" as a positive good is questionable. (Many popular things prove to be pernicious.) If we have a healthy nuclear infrastructure, we don't have any use, except in somewhat exotic situations, for so called "renewable energy." We wouldn't need it. We could let our rivers run free, avoid access roads in our wilderness, stop tearing the Earth to pieces with mines and laying concrete on the valuable benthic ecosystem.
It is a good thing to remind oneself of the origins of ideologies, less one forget how to address them.
Herr Rettburg finds himself almost laughing about how his country sees itself as a beacon to the world, this while burning coal and dumping the waste into the planetary atmosphere. He calls his country isolated. He lives in the area where the Grimms' wrote their fairy tales, and many of the landmarks of those fairy tales are familiar with him. The Grimms' of course, did not write The Emperor's New Clothes, but had they, they might have anticipated Energiewende.
Been there, done that. I have a positive Covid test.
I'm fully vaxxed and boosted, so I'm cheering for my T-cells to kick in and smack these dumbass viruses around.
As much as I cheer for them, they don't say very much; they're probably busy, those T-Cells. (Omicron evades antibodies, but not T-Cell epitopes.)
It feels like a very, very, very bad cold, but I've been crankily plugging along. It's been going on all weekend, stuffy nose, headaches, cough, but no fever.
How the Tonga eruption is helping space scientists understand Mars
This is a news item in Nature: How the Tonga eruption is helping space scientists understand Mars
Subtitle:
(Smriti Mallapaty News, Nature 20 Jan 2022.)
An excerpt:
The unusual explosion — which has been calculated at more than 500 times the force of the atom bomb dropped on Hiroshima, Japan, in 1945 — is offering researchers a rare chance to study how water and lava interact.
Related Story:
Tonga volcano eruption created puzzling ripples in Earth’s atmosphere
Studying the Hunga Tonga–Hunga Haʻapai volcano and its evolution in recent weeks is “important for planetary science”, says Petr Brož, a planetary volcanologist at the Institute of Geophysics of the Czech Academy of Sciences in Prague.
The knowledge “might help us to reveal results of water–lava interactions on the red planet and elsewhere across the Solar System”, he says.
Front-row seat
The volcanic island, which began to form from ash and lava expelled from an undersea volcano in early 2015, piqued the interest of researchers including James Garvin, chief scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, because of its similarity to structures on Mars and possibly also Venus. “We don’t normally get to see islands form,” explains Garvin, but this one offered “a front-row seat”.
Volcanic islands typically last for just months before being eroded away. But Hunga Tonga–Hunga Haʻapai survived for years, allowing Garvin’s team to use satellite observations and seafloor surveys to study how such islands form, erode and persist1. The researchers wanted to use that knowledge to understand how small conical volcanoes found on Mars may have formed in the presence of water billions of years ago...
The caption:
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