Fusion Energy on the Horizon? Again?

The big news recently as reported in Nature (13 December) was that researchers at the US National Ignition Facility carried out a reaction that made more energy than was put in. That looks great, right? The energy crisis is solved. Not so fast. What actually happened was that 192 lasers delivered 2.05 MJ of energy onto a pea-sized gold cylinder containing a frozen pellet of deuterium and tritium. The reason for all the lasers was to ensure that the input energy was symmetrical, and that caused the capsule to collapse under pressures and temperatures only seen in stars, and thermonuclear weapons. The hydrogen isotopes fused into helium, releasing additional energy and creating a cascade of fusion reactions. The laboratory claimed the reaction released 3.15 MJ of energy, roughly 54% more than was delivered by the lasers, and double the previous record of 1.3 MJ.

Unfortunately, the situation is a little less rosy than that might appear. While the actual reaction was a net energy producer based on the energy input to the hydrogen, the lasers were consuming power even when not firing at the hydrogen, and between start-up and shut-down they consumed 322 MJ of energy. So while more energy came out of the target than went in to compress it, if we count the additional energy consumed elsewhere but necessary to do the experiment, then slightly less than 1% of what went in came out. That is not such a roaring success. However, before we get critical, the setup was not designed to produce power. Rather it was designed to produce data to better understand what is required to achieve fusion. That is the platitudinal answer. The real reason was to help nuclear weapons scientists understand what happens with the intense heat and pressure of a fusion reaction. So the first question is, “What next?” Weapons research, or contribute towards fusion energy for peaceful purposes?

Ther next question is, will this approach contribute to an energy program. If we stop and think, the gold pellet of frozen deuterium had to be inserted, then everything line up for a concentrated burst. You get a burst of heat, but we still only got 3 MJ of heat. You may be quite fortunate to convert that to 1 MJ of electricity. Now, if it takes, say, a thousand second before you can fire up the next capsule, you have 1 kW of power. Would what you sell that for pay for the gold capsule consumption?

That raises the question, how do you convert the heat to electricity? The most common answer offered appears to be to use it to boil water and use the steam to drive a turbine. A smarter way might be to use magnetohydrodynamics. The concept is the hot gas is made to generate a high velocity plasma, and as that is slowed down, the kinetic energy of the plasma is converted to electricity. The Russians tried to make electricity this way by burning coal in oxygen to make a plasma at about 4000 degrees K. The theoretical maximum energy U is given by

    U  =  (T – T*)/T

where T is the maximum temperature and T* is the temperature when the plasma degrades and the extraction of further electricity is impossible. As you can see, it was possible to get approximately 60% energy conversion. Ultimately, this power source failed, mainly because the cola produces a slag which damaged the electrodes. In theory, the energy could be drawn in almost 100 % efficiency.

Once the recovery of energy is solved, there remains then problem of increasing the burn rate. Waiting for everything to cool down then adding an additional pellet cannot work, but expecting a pellet of hydrogen to remain in the condensed form when inserted into a temperature of, say, a million degrees, is asking a lot.

This will be my last post for the year, so let me wish you all a Very Merry Christmas, and a prosperous and successful New Year. I shall post again in mid-January, after a summer vacation.

Meanwhile, for any who fell they have an interest in physics, in the Facebook Theoretical Physics group, I am posting a series that demonstrates why this year’s Nobel Prize was wrongly assigned as Alain Aspect did not demonstrate violations of Bell’s inequality. Your challenge, for the Christmas period, is to prove me wrong and stand up for the Swedish Academy. If it is too difficult to find, I may post the sequence here if there were interest.

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A Solution to the Elements Shortage for Lithium Ion Batteries?

Global warming together with a possible energy crisis gives us problems for transport. One of the alleged solutions is battery powered cars. This gives three potential problems. One of these is how to generate sufficient electricity to power the batteries, but I shall leave that for the moment. The other two relate to chemistry. A battery (or fuel cell) has two basic electrodes: a cathode, which is positive, and an anode, which is negative. The difference in potential between these is the voltage, and is usually taken as the voltage at half discharge. The potential is caused by the ability to supply electrons to the anode while taking them at the cathode. At each there is a chemical oxidation/reduction reaction going on. The anode is most easily answered by oxidising a metal. Thus if we oxidise lithium we get Li  ➝ Li+  + e-. The electron disappears off to the circuit. We need something to accept an electron at the cathode, and that is Co+++, which gets reduced to the more stable Co++.  (Everything is a bit more complicated – I am just trying to highlight the problem.) Now superficially the cobalt could be replaced by a variety of elements, but the problem is the cobalt is embedded in a matrix. Most other ions have a substantial volume change of the ions, and if they are embedded in some cathode matrix, the stresses lead it to fall to bits. Cobalt seems to give the least stress, hence will give the batteries a longer life. So we have a problem of sorts: not enough easily accessible lithium, and not enough cobalt. There are also problems that can reduce the voltage or current, including side reactions and polarization.

In a fuel cell we can partly get over that. We need something at the cathode that will convert an input gas into an anion by accepting an electron, thus oxygen and water forms hydroxide. At the anode we need something that “burns”, i.e. goes to a higher valence state and gives up an electron. In my ebook “Red Gold”, a science friction story relating to the first attempt at permanent settlement of Mars, a portable power source was necessary. With no hidden oil fields on Mars, and no oxygen in the air to burn it if there were, I resorted to the fuel cell. The fuel cell chemistry I chose for Mars was to oxidize aluminium, which generates three electrons, and to reduce chlorine. The reason for these was that the settlement on Mars needed to make things from Martian resources, and the most available resource was the regolith, which is powdered rock. This was torn apart by nuclear fusion power, and the elements separated by magnetohydrodynamics, similar to what happens in a mass spectrometer. The net result is you get piles of elements. I chose aluminium because it has three electrons and hence more power capacity, and I chose chlorine because it is a liquid at Martian temperatures so no pressure vessel was required. Also, while oxygen might produce a slightly higher voltage, oxygen forms a protective coating on aluminium, and that stops that reaction.

An aluminium battery would have aluminium at the anode, and might have something in the electrolyte that could deposit more aluminium on it. Thus during a charge, you might get, if chlorine is the oxidiser,

4(Al2Cl7)-   + 3e-  → Al  +  7(AlCl4)-   

which deposits aluminium on the anode. During discharge the opposite happens and you burn aluminium off. Notice here the chlorine is actually tied up in chemical complexes and the battery has no free chlorine. Here, the electrolyte is aluminium chloride (Al2Cl6). For the fuel cell, we would be converting the gas to a complex at the cathode. That is not very practical on Earth, but the enclosed battery would be fine.

The main advantage of aluminium is that it gets rid of the supply problem. Aluminium is extremely common on Earth, as the continents are essentially made of aluminosilicates. The cathode can be simple carbon. A battery with this technology was proposed in 2015 (Nature 520: 325 – 328) that used graphite cathodes. It was claimed to manage 7,500 cycles without capacity decay, which looks good, but so far nobody seems to be taking this up.

Now, for an oddity. For discharge, we need to supply (AlCl4)- to the anode as it effectively supplies chlorine. Rather than have complicated chemistry at the cathode we can have an excess of AlCl4– from the start, and during charging, store it in the cathode structure. During discharge it is released. So now we need something to store it in. The graphite used for lithium-ion batteries comes to mind, but here is an oddity: you get twice the specific capacity, twice the cell efficiency and a 25% increase in voltage by using human hair! Next time you go to the hair dresser, note that in the long term that might be valuable. Of course, before we get too excited, we still need such batteries to be constructed and tested because so far we have no idea how such hair stands up to repeated cycles.

What we do not know about such batteries is how much dead weight has to be carried around and how small they can be made for a given charge. The point about cars is that eventually the critical point is how far will it go on one charge, how long does it take to safely recharge, how much volume of the vehicle does it take, and is it flammable? The advantage of the aluminium chloride system described above is that there are probably no side reactions, and a fire is somewhat unlikely. The materials are cheap. So, the question is, why hasn’t more been done on this system? My guess is that the current manufacturers know that lithium is working, so why change? The fact that eventually they will have to does not bother them. The accountants in charge think beyond the next quarter is long-term. Next year can look after itself. Except we know that when the problem strikes, it takes years to solve it. We should get prepared, but our economic system does  not encourage that.

This and That from the Scientific World

One of the consequences of writing blogs like this is that one tends to be on the lookout for things to write about. This ends up with a collection of curiosities, some of which can be used, some of which eventually get thrown away, and a few I don’t know what to do about. They tend to be too short to write a blog post, but too interesting, at least to me, to ignore. So here is a “Miscellaneous” post.

COP 27.

They agreed that some will pay the poorer nations for damage so far, although we have yet to see the money. There was NO promise by anyone to reduce emissions, and from my point of view, even worse o promise to investigate which technologies are worth going after. Finally, while at the conference there were a number of electric buses offering free rides, at the end of the conference these buses simply disappeared. Usual service (or lack thereof) resumed.

Fighting!

You may think that humans alone fight by throwing things at each other but you would be wrong. A film has been recorded ( https://doi.org/10.1038/d41586-022-03592-w) of two gloomy octopuses throwing things at each other, including clam shells. Octopuses are generally solitary animals, but in Jervis Bay, Australia, the gloomy octopus lives at very high densities, and it appears they irritate each other. When an object was thrown at another one, the throw was far stronger than when just clearing stuff out of the way and it tended to come from specific tentacles, the throwing ones. Further, octopuses on the receiving end ducked! A particularly interesting tactic was to throw silt over the other octopus. I have no idea what the outcome of these encounters were.

Exoplanets

The star HD 23472 has a mass of about 0.67 times that of our sun, and has a surface temperature of about 4,800 degrees K. Accordingly, it is a mid-range K type star, and it has at least five planets. Some of the properties of these include the semi-major axis a (distance from the star if the orbit is circular), the eccentricity e, the mass relative to Earth (M), the density ρ  and the inclination i. The following table gives some of the figures, taken from the NASA exoplanet archive.

Planet     a              e            M        ρ           i

b           0.116      0.07       8.32      6.15      88.9

c           0.165      0.06       3.41      3.10      89.1

d           0.043      0.07       0.55      7.50      88.0

e           0.068      0.07       0.72      7.50      88.6

f           0.091      0.07       0.77       3.0        88.1

The question then is, what to make of all that? The first thing to notice is all the planets are much closer to the star than Earth is to the sun. Is that significant? Maybe not, because another awkward point is that the inclinations are all approaching 90 degrees. The inclination is the angle the orbital plane of the planet makes with the equatorial plane of the star. Now planets usually lie on the equatorial plane because that was also the plane of the accretion disk, so something has either moved the planets, or moved the star. Moving the planets is most probable, and the reason the inclinations are all very similar is because they are close together, and they will probably be in some gravitational resonance with each other. What we see are two super Earths (b and c), two small planets closest to the star, which are small, but very dense. Technically, they are denser than Mercury in our system. There are also two planets (c and f) with densities a little lower than that of Mars.

The innermost part of the habitable zone of that star is calculated to be at 0.364 AU, the Earth-equivalent (where it gets the same radiation as Earth) at 0.5 AU, and the outer boundary of the habitable zone is at 0.767 AU. All of these planets lie well inside the habitable zone. The authors who characterised these planets (Barros, S. C. C. et al. Astron. Astrophys. 665, A154 (2022).) considered the two inner planets to be Mercury equivalents, presumably based on their densities, which approximate to pure iron. My guess is the densities are over-estimated, as the scope for error is fairly large, but they certainly look like Mercury equivalents that are somewhat bigger than our Mercury

Laughing Gas on Exoplanets

One of the targets of the search for exoplanets is to try and find planets that might carry life. The question is, how can you tell? At present, all we can do is to examine the spectra of atmospheres around the planet, and this is not without its difficulties. The most obvious problem is signal intensity. What we look for is specific signals in the infrared spectrum and these will arise from the vibrations of molecules. This can be done from absorptions if the planet transits across the star’s face or better (because the stellar intensity is less a problem) from starlight that passes through the planet’s atmosphere.

The next problem is to decide on what could signify life. Something like carbon dioxide or methane will be at best ambiguous. Carbon dioxide makes up a huge atmosphere on Venus, but we do not expect life there. Methane comes from anaerobic digestion (life) or geological activity (no life). So, the proposal is to look for laughing gas, better known as nitrous oxide. Nitrous oxide is made by some life forms, and oddly enough, it is a greenhouse gas that is becoming more of a problem from the overuse of agricultural fertilizer, as it is a decomposition product of ammonium nitrate. If nothing else, we might find planets with civilizations fighting climate change!

Reducing Electricity Usage in Your Refrigerator

When thinking about battling climate change, did you know that a major electricity consumer in your house is your refrigerator? The International Institute of Refrigeration (yes, there are institutes for just about everything) estimates that about 20% of all electricity used is expended on vapour compression refrigeration. The refrigerator works by compressing a vapour, often some sort of freon, or in industry, with ammonia, and when compressed it gives off heat. When you ship it somewhere else and expand it, the somewhere else gets colder. This is also the principle of the heat pump and various air conditioning units. Compress gas here to add heat from a heat exchanger; ship the gas there and expand it, where it cools a heat exchanger. The compression and expansion of gas moves heat from A to B, hence the name heat pump. Also, the refrigerant gases tend to be powerful greenhouse gases. One kilogram of R410a has the same greenhouse impact as two tonne of carbon dioxide. Refrigerants leak into the atmosphere from faulty equipment or when equipment is not properly disposed of.

It is possible to heat or cool without any gas through the Peltier effect. Basically, when electric current passes between two conductors, heating or cooling effects may be generated. There are commercial solid-state such cooling systems, but they suffer from high cost and poor efficiency, in part because the effect is restricted to the specific junction.

There is an alternative. Some solid state materials can cool when they are subjected to strain, which is generated from an external field, such as  the electric or magnetic fields, or simply pressure. So far most efforts have been focused on the magnetic field, and one material, Mn3SnC apparently gives significant cooling,  but the magnetic field has to be greater than 2 tesla. That means expensive and bulky magnets, and additionally the refrigerator, if it used them, would have to be a “no-go” area for credit cards, and possibly people with a pacemaker. Even aside from direct messing with the pacemaker, losing all those bitcoin just because you wanted a cool beer could lead to medical problems.

However, there has been an advance. Wu et al. (Acta Materiala 237: 118154) have taken the Mn3SnC and coated it with a piezoelectric layer of lead zirconate titanate. Don’t ask me how they come up with these things; I have no idea, but this is certainly interesting. They probably do it by looking through the literature to find materials already known to have certain properties. Thus a piezoelectric effect is where you generate an electric voltage by applying pressure. Such effects are reversible so if you can generate a voltage by applying pressure to something, you can generate pressure by applying a potential difference. Recall that pressure also can generate a cooling effect. Accordingly, by applying an electric field to this coated material a cooling effect was obtained equivalent to that of a 3 tesla magnetic field. When the electric field is removed, the temperature returns to where it was. How useful will this be? Hard to tell right now. The temperature drop when applying a field of 0.8 kV/cm was slightly under 0.6 of a degree Centigrade, which is not a huge change while the voltage is tolerably high. Interestingly, if you apply a magnetic field you also get a temperature change, but in the opposite direction – instead of cooling, it heats. Why that is is unclear.

As you might guess, there is still a significant distance to go before we get to a refrigerator. First, you have to get the cooling into some other fluid that can transport it to where you need it. To do that you have to take the heat out of the cooling fluid, but that will heat up your unit, so you need another fluid to take the heat to where it can be dissipated. We have very roughly the same cycle as our present system except we are not compressing anything but we have two fluids. Except I rather think we will be, because pumping a fluid involves increasing its pressure so it flows. The alternative is to put the material across the rear wall of the refrigerator thus to cool the interior and have the heat dissipated out the back. The problem now is the change of temperature is rather small for the voltage. This is not so much a problem with fluids transporting it, but if the solids transport it, the solids are always heated by the environment so your temperature drop is from the room temperature. Half a degree is not very helpful, although you could increase the electric field. Unfortunately, to get a big enough temperature change you might be into the spark jumping region. Lightning in the kitchen! Finally, do you want the back of your refrigerator to be carrying even a kilovolt electric field? My guess is this effect may remain a curiosity for some length of time.

Economic Consequences of the Ukraine War

My last post mentioned the USSR collapse. One of the longer term consequences has been this Ukraine war. Currently, there have been problems of shelling of the Zaporizhzhia nuclear plant, and this appears to have happened in that our TV news has shown some of the smashed concrete, etc. The net result is the plant has shut down. Each side accuses the other of doing the shelling, but it seems to me that it had to be the Ukrainians. Russia has troops there, and no military command is going to put up with his side shelling his own troops. However, that is far from the total bad news. So far, Ukraine has been terribly lucky, but such luck cannot last indefinitely. There are consequences outside the actual war itself. The following is a summary of some of what was listed in the August edition of Chemistry World.

The Donbas area is Ukraine’s heavy industry area, and this includes the chemical industry. Recently, Russian air strikes at Sieverierodonetsk hit a nitric acid plant, and we saw images of the nitrogen dioxide gas spewing into the atmosphere.

Apparently, in 2017 Ukrainian shelling was around a chemical plant that contained 7 tonne of chlorine. Had a shell hit a critical tank, that would have been rather awkward. Right now, in the eastern Donbas there is a pipeline almost 700 km long that pipes ammonia. There are approximately 1.5 million people in danger from that pipeline should it burst; exactly how many depends on where it is broken. There are also just under  200,000 t of hazardous waste stored in various places. The question now is, with all this mess generated, in addition to demolished buildings and infrastructure, who will pay what to clean it up? It may or may not be fine for Western countries to use their taxes to produce weapons to give to Ukraine, but cleaning up the mess requires the money to go to Ukraine, not armament-making corporations at home.

The separation of the Donbas has led to many mines being closed, and these have filled with water. This has allowed mercury and sulphuric acid to be leached and then enter the water table. During 2019, a survey of industrial waste was made, and Ukraine apparently stores over 5.4 billion t of industrial waste, about half of which is in the Donbas. Ukraine has presumably inherited a certain amount, together with some of the attitudes, from the old Soviet Union. From experience, their attitude to environmental protection was not their strong point. I recall  one very warm sunny morning going for a walk around Tashkent. I turned a corner and saw rather a lot of rusty buildings, and also, unbelievably, a cloud. How could water droplets form during such a warm dry climate? The answer was fairly clear when I got closer. One slight whiff, and I knew what it was: the building was emitting hydrogen chloride into the atmosphere and the hydrochloric acid droplets were the reason for the rust.

Meanwhile, some more glum news. We all know that the sanctions in response to the Ukraine war has led to a gas shortage. What most people will not realize is what this is doing to the chemical industry. The problem for the chemical industry is that unlike most other industries, other than the very sophisticated, the chemical industry is extremely entangled and interlinked. A given company may make a very large amount of chemical A, which is then sold as a raw material to a number of other companies, who in turn may do the same thing. There are many different factories dependent on the same raw chemical and the material in a given chemical available to the public may have gone through several different steps in several different factories.

An important raw mixture is synthesis gas, which is a mix of carbon monoxide and hydrogen. The hydrogen may be separated and used in steps to make a variety of chemicals, such as ammonia, the base chemical for just about all nitrogen fertilizer, as well as a number of other uses. The synthesis gas is made by heating a mixture of methane gas and water. Further, almost all chemical processing requires heat, and by far the bulk of the heat is produced by burning gas. In Europe, the German government is asking people to cut back on gas usage. Domestic heating can survive simply by lowering the temperature, although how far down one is prepared to go during winter is another question. However, the chemical industry is not so easily handled. Many factories use multiple streams, and it is a simple matter to shut down such a stream, but you cannot easily reduce the amounts going through a stream because the reactions are highly dependent on pressure, and the plant is in a delicate balance between amount processed and heat generated.  A production unit is really only designed to operate one way, and that is continuously with a specific production rate. If you close it down, it may take a week to get it started again, to get the temperature gradients right. One possibility is the complete shutdown of the BASF plant at Ludwigshafen, the biggest chemical complex in the world. The German chemical industry uses about 135 TWhr of gas, or about 15% of the total in the country. The price of such gas has risen by up to a factor of eight since Russia was sanctioned, and more price rises are likely. That means companies have to try to pass on costs, but if they face international competition, that may not be possible. This war has consequences far beyond Ukraine.

Gorbachev: A Man for What Season?

Mikhail Sergeyevich Gorbachev is dead, and the eulogies are flowing thick and fast, but mainly from those outside Russia. He may well have the record for the most praise for someone who made the worst botch-up of the job he was appointed to do. He is praised in the West for dismantling the Soviet Union, but that was the last thing he was trying to do. He believed that liberalizing the economy would improve the lot of Russians. After he was deposed and the USSR fell, the GDP of Russia almost halved, and only too much that was left fled the country in the hands of a few oligarchs. You see comments by Bill Browder on how bad Putin is, but he made a billion dollars from the ignorance of the ordinary Russian and according to Russia, he never paid a cent in tax to Russia. Quite simply, Gorbachev gave the country that hated Russia (the US) what it wanted and completely failed Russia. He had a dream, but he never checked to see whether it was realistic, and he never had a workable plan to implement it.

Gorbachev’s early important jobs related to agriculture. The Soviet Union should have been a major food exporter, but in the 1970s, in part because of poor weather, it had to import grain. Gorbachev was supposed to do something about this, and his response was to blame central decision-making. That may well have been a factor, but it was not the required answer. I visited the USSR in the early 1980s, and in a drive through the countryside of Uzbekistan the problem was easy to see. There were huge areas of the steppe that had been ploughed, and then, nothing. Not even harrowed to at least make it look as if something was being done. But in small “oases” there was extremely intense productivity. Those in the collective were given very small areas of land for themselves to use, and basically they concentrated on that. This was where almost all the local food came from, a tiny percentage of the total land. Now, if I could see this in a short visit which was really more as a tourist (I was getting over jet lag and enjoying a weekend before heading to Moscow for what I went there for) surely Gorbachev could have found this out if he wanted to.

Part of my life has been devoted as a consultant to fixing problems, and my first rule of fixing a problem has always been, first examine the problem in intense detail and understand it. To examine it, you actually have to go and look at it yourself. Reading a report is no good unless there is a recommendation to fix it, because if whoever wrote the report does not know how to fix it, perforce (s)he does not understand it. This is probably a major failing of leaders everywhere, but it was much worse in the USSR. If the leader cannot take the time off to look at it, he should delegate to someone who can. At this time fixing agriculture was Gorbachev’s main job; he was the delegated man, and at this point he failed. The USSR kept importing food, which also was a drain on foreign currency. One could argue that the system prevented success, but Gorbachev had Yuri Andropov as a friend, and if he could persuade Andropov, almost certainly what he recommended would be done. The simple answer is the farmers had to have an incentive to increase the communal yield. That introduces the most significant problem in economics: how to properly reward people. Something needed to be tried, such as giving small groups of farmers (since they had to maintain some part of communism) the right to take shares of the yield from a block of the commune land.

When Gorbachev became effectively the leader of the USSR, he had learned nothing from his agrarian program, and while he recognized industry needed a better output and productivity, he still relied on central planning, while ignoring implementation. A plan that might work is only of use if there is a working procedure to make it work. For his plans to work, first he had to remove the many layers of bureaucrats between the major decision and implementation. His first move was to remove the “old guard”. This was a clear mistake as a first move. They knew someone younger was needed, which was why they put him there. Many should have been potential allies. His replacements included people like Yeltsin, who ended up doing everything he could to subvert Gorbachev. Gorbachev was not a good judge of character, and completely failed the next step: if you want to run a central system the top priority is to find someone who gets things done. They are seldom people who play the political game making fine speeches praising Lenin. Gorbachev tried to introduce some sort of limited private enterprise and market economics, but because of the layer of incompetents under him and his demand that central planning be retained, that did not work.

The next major blunder was “glasnost”; giving the people the right to complain. There was too much to complain about. Freedom to criticize is all very well, but if the criticisms are going to be well-grounded and nobody is fixing them, the society fragments. Gorbachev apparently thought that if the people knew about all the problems they would rally behind his efforts to fix them. That was ridiculous. The noisiest dissidents are the least constructive. He needed fixers in place before allowing people to shout out what needed fixing. After all, a lot was obvious. Again, I recall going into a building in the old USSR that was supposed to be where you bought things. The shelves were empty. Fixing food production and providing a range of consumable goods should have been the first priority. If everyone had more to purchase, and higher incomes from the increased productivity, now open criticism would be harmless.

Gorbachev made an impression on Western leaders. The nuclear disarmament treaty was an achievement, but when it came to the reunification of Germany and the USSR giving the Warsaw Pact countries their independence from Moscow control, Gorbachev badly needed to ensure that NATO did not march East. Given that he was offering a lot, he needed a signed treaty ensuring the “neutral zone”. He could have obtained that from the Eastern countries, although he probably also needed the US to agree, but for some reason he made no effort at all, which eventually brings us to the current Ukraine conflict. He was to permit some of the republics to leave the USSR, but he made no effort to settle the legal conditions of doing so, which later led to the Georgian and now Ukrainian problems. The USSR owned all the factories, etc, in the breakaway republics, but these ended up in the hands of a very few oligarchs.  Gorbachev had great ideas, but was seemingly uninterested in the details of achieving them, or of ensuring decisions were not undermined by others. The end result was the rule of Yeltsin, and the impoverishment of a very large fraction of the population, the transfer of virtually all of Russia’s industrial and resource assets into the hands of a few oligarchs, the almost halving of the nation’s GDP, and all this really followed from Gorbachev’s inept governance. Gorbachev seemed to think people would rally behind to get the best outcome. That is delusional. They follow incentives or they fly off in different directions. He failed to provide incentives or control where things went. He achieved nothing of substance for those who depended on him. He is popular with those who took advantage of him.

Nuclear War is Not Good

Yes, well that is sort of obvious, but how not good? Ukraine has brought the scenario of a nuclear war to the forefront, which raises the question, what would the outcome be? You may have heard estimates from military hawks that apart from those killed due to the blasts and those who got excessively irradiated, all would be well. Americans tend to be more hawkish because the blasts would be “over there”, although if the enemy were Russia, Russia should be able to bring it to America. There is an article in Nature (579, pp 485 – 487) that paints a worse picture. In the worst case, they estimate deaths of up to 5 billion, and none of these are due to the actual blasts or the radiation; they are additional extras. The problem lies in the food supply.

Suppose there was a war between India and Pakistan. Each fires nuclear weapons, first against military targets, then against cities. Tens of millions die in the blasts. However, there is a band of soot that rises into the air, and temperatures drop. Crop yields drop dramatically from California to China, and affect dozens of countries. Because of the limited food yields, more than a billion people will suffer from food shortages. The question then is, how valid are these sort of predictions?

Nuclear winter was first studied during the cold war. The first efforts described how such smoke would drop the planet into a deep freeze, lasting for months, even in summer. Later studies argued this effect was overdone and it would not end up with such a horrific chill, and unfortunately that has encouraged some politicians who are less mathematically inclined and cannot realize that “less than a horrific chill” can still be bad.

India and Pakistan each have around 150 nuclear warheads, so a study in the US looked into what would happen in which the countries set off 100 Hiroshima-sized bombs. The direct casualties would be about 21 million people. But if we look at how volcanic eruptions cool the planet, and how soot goes into the atmosphere following major forest fires, modelling can predict the outcome. A India-Pakistan war would put 5 million tonne of soot into the atmosphere, while a US Russian war would loft 150 million tonne. The first war would lower global temperatures by a little more than 1 degree C           , but the second would lower it by 10 degrees C, temperatures not seen since the last Ice Age. One problem that may not be appreciated is that sunlight would heat the soot, and by heating the adjacent air, it causes it to rise, and therefore persist longer.

The oceans tell a different story. Global cooling would affect the oceans’ acidity, and the pH would soar upwards (making it more alkaline). The model also suggested that would make it harder to form aragonite, making life difficult for shellfish. Currently, the shellfish are in the same danger from too much acidity; depending on aragonite is a bad option! The biggest danger would come regions that are home to coral reefs. There are some places that cannot win. However, there is worse to come: possibly a “Nuclear Niño”, which is described as a “turbo-charged El Niño”. In the case of a Russia/US war, the trade winds would reverse direction and water would pool in the eastern pacific ocean. Droughts and heavy rain would plague different parts of the world for up to seven years.

One unfortunate effect is that this is modelled. Immediately, another group from Los Alamos carried out different calculations and came to less of a disastrous result. The difference depends in part on how they simulate the amount of fuel, and how that is converted to smoke. Soot comes from partial combustion, and what happens where in a nuclear blast is difficult to calculate.

The effects on food production could be dramatic. Even following the small India-Pakistan war, grain production could drop by approximately 12% and soya bean production by 17%. The worst effects would come from the mid-latitudes such as the US Midwest and Ukraine. The trade in food would dry up because each country would be struggling to feed itself. A major war would be devastating, for other reasons as well. It is all very well to say your region might survive the climate change, and somewhere like Australia might grow more grain if it gets adequate water, as at present it is the heat that is the biggest problem. But if the war also took out industrial production and oil production and distribution, now what? Tractors are not very helpful if you cannot purchase diesel. A return to the old ways of harvesting? Even if you could find one, how many people know how to use a scythe? How do you plough? Leaving the problem of knowing where to find a plough that a horse could pull, and the problem of how to set it up, where do you find the horses? It really would not be easy.

Burying Carbon Dioxide, or Burying Cash?

In the last post, I expressed my doubt about the supply of metals for electric batteries. There is an alternative to giving up things that produce CO2 and that is to trap and sequester CO2. The idea is that for power stations the flu gases have the CO2 removed and pumped underground. That raises the question, how realistic is this? Chemistry World has an article that casts doubt, in my mind, that this can work. First, the size of the problem. One company aims to install 70 such plants, each capable of sequestering 1 million t of CO2. If these are actually realized, we almost reach 0.2% of what is required. Oops. Basically, we need to remove at least 1 billion t/a to stand still. This problem is large. There is also the problem of how we do it.

The simplest way is to pass the flu gases through amine solvents, with monoethanolamine the most common absorbent used. Leaving aside the problem of getting enough amine, which requires a major expansion of the chemical manufacturing industry, what happens is the amine absorbs CO2 and makes the amine carbonate, and the CO2 is recovered by heating the carbonate and regenerating the amine. However, the regeneration will never be perfect and there are losses. Leaving aside finding the raw materials actually synthesizing the amine takes about 0.8 MWh of energy, the inevitable losses mean we need up to 240 MWh every year to run a million tonne plant. We then need heat to decompose the amine carbonate, and that requires about 1 MWh per tonne of CO2 absorbed. Finally, we need a little less than 0.12 MWh per tonne of CO2 to compress it, transport it and inject it into the ground. If we wanted to inject 1 billion t of CO2, we need to generate something like 840 TWh of electricity. That is a lot of electricity.

We can do a little better with things called metal organic frameworks (MOFs).These can be made with a high surface energy to absorb CO2 and since they do not form strong chemical bonds the CO2 can be recovered at temperatures in the vicinity of  80 – 100 degrees C, which opens the possibility of using waste heat from power stations. That lowers the energy cost quite a bit. Without the waste heat the energy requirement is still significant, about half that of the amines. The comes the sting – the waste heat approach still leaves about 60% of what was absorbed, so it is not clear the waste heat has saved much. The addition of an extra step is also very expensive.

The CO2 content of effluent gases is between 4 – 15%; for ordinary air it is 0.04%, which makes it very much more difficult to capture. One proposal is to capture CO2 by bubbling air through a solution of potassium hydroxide, and then evaporating off the water and heating the potassium carbonate to decomposition temperature, which happens to be about 1200 degrees C. One might have thought that calcium oxide might be easier, which pyrolyses about 600 degrees C, but what do I know? This pyrolysis takes about 2.4 MWh per tonne of CO2, and if implemented, this pyrolysis route that absorbs CO2 from the air would require about 1.53 TWh of electricity per year for sequestering 1 million t of CO2.

When you need terawatt hours of electricity to run a plant capable of sequestering one million tonne of CO2, and you need to sequester a billion t, it becomes clear that this is going to take an awful lot of energy. That costs a lot money. In the UK, electricity costs between £35 – 65 per MWh, and we have been talking in terms of a million times that per plant. Who pays? Note this scheme has NO income stream; it sells nothing, so we have to assume it will be charged to the taxpayer. Lucky taxpayer!

One small-scale effort in Iceland offers a suggested route. It is not clear how they capture the CO2, but then they dissolve it in water and inject that into basalt, where the carbonic acid reacts with the olivine-type structures to make carbonates, where it is fixed indefinitely. That suggests that provided the concentration of CO2 is high enough, using pressure to dissolve it in water might be sufficient. That would dramatically lower the costs. Of course, the alternative is to crush the basalt and spread it in farmland, instead of lime. My preferred option to remove CO2 from the air is to grow plants. They work for free at the low concentrations. Further, if we select seaweed, we get the added benefit of improving the ecology for marine life. But that requires us to do something with the plants, or the seaweed. Which means more thinking and research. The benefit, though, is the scheme could at least earn revenue. The alternatives are to bankrupt the world or find some other way of solving this problem.

Limits to Growth

A little over fifty years ago, the Systems Dynamics group at MIT produced a 200-page book called The Limits to Growth. Their message was, continued economic and population growth would deplete Earth’s resources and lead to global economic collapse by 2070. At the time, this was considered heresy. The journal Nature was scathing (See vol 236, pp 47 – 49, 1972). How could the foundations of industrial civilization, such as coal mining, steel-making, oil production, crop spraying, cause lasting damage? It was accepted that such industries caused pollution, but such effects were considered to be only temporary. At the time computer modelling was looked down upon. This is understandable; at the time computers were quite primitive compared with now, and big computers were only available to the major organizations. I recall four years before that someone doing a chemical bond calculation and coming back from the computer with what looked like a couple of kg of printout. His problem was that his program only produced two answers, depending on what he changed in the code. The answers were zero or infinity. As I remarked, the truth would be somewhere in between.

It is unlikely that any other computer model has made a bigger impact. There are still debates, but it is now clear that our activities have made irreversible environmental effects. As I have also noted in a previous post, there is also significant resource depletion. The elements have not gone anywhere, but that does not help if they are so diluted with other material that we cannot use them. Of course, it is arguable we could with unlimited energy, but we do not have that. The sun effectively produces unlimited energy, but it is too far away; here all it delivers is approximately 1360 W/m^2 at the top of the atmosphere, which is reduced to somewhere between 1000 – 1150 W/m^2 on a surface at right angles to the radiation at the surface. These numbers have to be divided by three for a 24-hr day, assuming no clouds.

The obvious problem for people is economic growth. Some people assume that economic growth can continue if we adopt technology much faster, particularly employing more renewable energy. Others argue we have to abandon the idea of growth. Was living as per we did in, say, 2016 that bad? One problem is that politicians need votes, and to get them they want to raise GDP. Thus if there is a choice of what to do, politicians will go for that which produces the most jobs. Excessive spending on the military increases jobs; corresponding spending on healthcare does not, but which is the more useful?

One analysis (Rockström et al. 2009, Nature 461: 472 – 475) argued there were boundaries. If we stayed within these the planet would adjust and correct our behaviour, but as we approached those boundaries (i.e. too much of something is being emitted) the planet may respond in a non-linear and often in an abrupt way. Most of these thresholds depend on one, or sometimes more, variables. They suggest ten such processes have such boundaries, three of which, biodiversity loss, climate change, the nitrogen cycle, are already exceeded, while a fourth, the phosphorus cycle is close to the breaking point and a fifth, ocean acidification is troublesome. Two more, chemical pollution and atmospheric aerosol loading were not quantified. Three, fresh water use, land use, and ozone depletion are considered to be under control.

The last time the poles were essentially ice-free the CO2 levels were approximately 450 ppm. As can be seen from my last post, exceeding that seems inevitable without drastic action. For biodiversity, extinctions are currently about 100 – 1000 times greater than natural. Biodiversity is very important to maintain the resilience of the system. The production of nitrogen fertilizer and the cultivation of legumes convert around 120 million t/a of nitrogen, which is more than the combined efforts of all Earth’s terrestrial processes. This ends up as pollution, it erodes resilience of some of the plant life, and it sends nitrous oxide into the atmosphere, and this makes a major contribution to greenhouse forcing. Excess nitrogen fertiliser leads to turbid waterways, lakes, etc, and sometimes pronounced algal blooms. About 20 Mt of phosphorus is mined each year, and about half of this finds its way into oceans. This is around eight times the natural erosion rate. When critical levels of phosphate enter the oceans, large scale anoxic events occur, which can lead to mass extinctions of marine life. The authors conclude that as long as we do not exceed the thresholds, we can pursue long-term economic and social development. Our problem is, we are crossing some.

Energy Sustainability

Sustainability is the buzzword. Our society must use solar energy, lithium-ion batteries, etc to save the planet, at least that is what they say. But have they done their sums?. Lost in this debate is the fact that many of the technologies use relatively difficult to obtain elements. In a previous post I argued that battery technology was in trouble because there is a shortage of cobalt, required to make the cathode work for a reasonable number of cycles. Others argue that we could obtain sufficient elements. But if we are going to be sustainable, we have to be sustainable for an indefinite length of time, and mining is not sustainable; you can only dig up the ore once. Of course, there are plenty of elements left. There is more gold in the sea than has ever been mined; the problem is that it is too dilute. Similarly, most elements are present in a lump of basalt; just not much of anything useful and it is extremely difficult to get it out. The original copper mines of Cyprus, where even lumps of copper could occasionally be found, are all worked out, at least to the extent that mining is no longer profitable there.

The answer is to recycle, right? Well, according to an article [Charpentier Poncelet, A. et al. Nature Sustain. https://doi.org/10.1038/s41893-022- 00895-8 (2022)] there are troubles. The problem is that even if we recycle, every time we do something we lose some of the metal. Losses here refer to material emitted into the environment, stored in waste-disposal facilities, or diluted in material where the specific characteristics of the elements are no longer required. The authors define a lifetime as the average duration of their use, from mining through to being entirely lost. As with any such definition-dependent study, there will be some points where you disagree.

The first loss for many elements lies in the production state. Quite often it is only economical to obtain one or two elements, and the remaining minor components of the ore disappear in slag. These losses are mainly important for specialty elements. Production losses account for 30% of rare earth metals, 50% for cobalt, 70% for indium, and greater than 95% for arsenic, gallium, germanium, hafnium, selenium and tellurium. So most of those elements critical for certain electronic and photo-electric effects are simply thrown out. We are a wasteful lot.

Manufacturing and use incur very few losses. There are some, but because materials are purified ready for use, pieces that are not immediately used can be remelted and used. There are exceptions. 80% of barium is lost through use; it is used in drilling muds.

The largest losses come from the waste management and recycling stage. Metals undergoing multiple life cycles are still lost this way; it just takes longer to lose them. Recycling losses occur when the metal accumulates in a dust (zinc) or slag(e.g. chromium or vanadium), or get lost in another stream, thus copper is prone to dissolve in an iron stream. Longest lifetimes occur for non-ferrous metals (8 to 76 years) precious metals (4 to 192 years), and ferrous metals (8 to 154 years). The longest lifetimes are for gold and iron.

Now for the problem areas. Lithium has a life-cycle use of 7 years, then it is all gone. But lithium-ion batteries last about this long, which suggests that as yet (if these data are correct) there is very little real recycling of lithium. Elements like gallium and tellurium last less than a year, while indium manages a year. Before you protest that most of the indium goes into swipeable mobile phone screens and mobile phones last longer than a year, at least for some of us, remember that losses occur through being discarded at the mining stage, where the miner/processor can’t be bothered. Of the fifteen metals most lost during mining/processing, thirteen are critical for sustainable energy, such as cobalt (lithium-ion batteries), neodymium (permanent magnets), indium, gallium, germanium, selenium and tellurium (solar cells) and scandium (solid oxide fuel cells). If we look at the recycled content of “new material” lithium is less than 1% as is indium. Gallium and tellurium are seemingly not recycled. Why are they not recycled? Metals that are recycled tend to be like iron, aluminium, the precious metals and copper. It is reasonably easy to find uses for them where purity is not critical. Recycling and purifying most of the others requires technical skill and significant investment. If we think of lithium-ion batteries, the lithium reacts with water, and if it starts burning it is unlikely to be put out. Some items may have over a dozen elements, and some are highly toxic, and not to be in the hands of the amateur. What we see happening is that the “easy” metals are recycled by organizations that are really low-technology organizations. It is not an area attractive to the highly skilled because the economic risk/return is just not worth it, while the less-skilled simply cannot do it safely.