an autodidact meets a dilettante…

‘Rise above yourself and grasp the world’ Archimedes – attribution

advancing solar 2 – more on electrons, holes, dopants and electromagnetic fields

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Jacinta: So in the last post we were joking about the horrors of physicists and engineers manipulating innocent electrons and forcing them to work for us, gratis. It comes to mind that there are people who are intelligently dubious about the manipulations of scientists – Bernard Beckett, in his 2007 book Falling for science, comes to mind, as does Yuval Noah Harari in Homo deus. ‘Scientism’ was used for a while as a pejorative, especially during the debates on the values of religion ‘versus’ science…

Canto: Yeah, but – I don’t want to dwell on this issue now, except to say that the critics of science are usually not very literate on the subject. So we were talking about dopants, which are impurities that can be added to the silicon crystal lattice to mess up its fine balance, so to speak. Boron is an example – it has three electrons ready for bonding, leaving a ‘hole’, a p-type space, and presumably a loose electron to carry the charge. And then there’s phosphorus, which has five such electrons – so one to spare after bonding, which they call an n-type situation. Positive charge carriers (p-type) and negative charge carriers (n-type) is how they describe it.

Jacinta: Right, so they layer these two types together: ‘The positive holes and negative electrons migrate towards each other’. The electrons will jump into the p-type and the holes jump into the n-type [they don’t explain how holes can jump]. This causes an imbalance of charge, because now the p-type side has more negative charges, and the n-type side has more positive charges’. This apparently creates an ‘electromagnetic valve’, which allows, or perhaps forces, electrons to pass through in one direction only.

Canto: This isn’t very clear to me, but let’s continue. Maybe you have to do it, and so see it working, to get a full grasp. So, a sufficiently energetic photon enters the p-type side (the boron-doped side) of the solar cell, knocking an electron loose to float within the material. It will either recombine with a hole, and fail to create a current, or it can enter the electromagnetic field – that valve thing between the p-types and n-types, also called a depletion layer for some reason. The effect, apparently, is that it accelerates the electron into the n-type side, which of course tends to lack p-type ‘holes’, but the electromagnetic field most cruelly prevents the electron from passing back to the p-type side.

Jacinta: Yes, it’s still a bit fuzzy, but on the n-type side some ‘holes’ are somehow transported across this electromagnetic field junction, where they recombine with electrons. so one side of this junction or valve becomes negatively charged, the other positive. This creates a ‘potential difference’, aka a voltage!

Canto: Explained neatly for us as ‘The difference in electric potential between two points, which is defined as the work needed per unit of charge to move a test charge between the two points’. Just saying.

Jacinta: So, as our video-maker tells us, we can then add ‘some mental contacts and an external load circuit’ and we have created a current, presumably, as the electrons will ‘pass along the circuit to recombine with the holes on the other side’. And that’s your solar cell, apparently. But I barely understand a word.

Canto: Well, doing and seeing, as I’ve said. But there’s problem with adding this metal to the upper surface as it blocks some of the light needed for the cell to function effectively. So, problems with solutions that create problems. So engineers keep working on new shapes and materials for optimisation. They’re trying to minimise the metal coverage and electron resistance in getting into the circuit. Topology optimisation is one subject of research, using computerised algorithms.

Jacinta: And it’s fascinating but hardly surprising that this sort of research is producing shapes for solar cells that resemble leaves – which after all are like little solar cells resulting from millions of years of evolution.

Canto: Hmmm, not like ours, plants don’t use the sun to make electricity. But this quote from the video is thought-provoking:

Vascular tissue on a leaf does not perform photosynthesis. It instead brings the water that is essential for photosynthesis to the leaf and extracts the useful products, serving a similar purpose as our electric contacts – so of course plants have developed the perfect shape to optimise the energy they can absorb from the sun… However, most solar cells use a simple grid shape, as it is cheap to manufacture.

Inevitably this means an efficiency loss, measured at around 8%. So, in conclusion, a current silicon solar cell has an efficiency, under lab testing, of around 20%. The drop to 18% shortly after operating has resulted in hundreds of scientific papers, and it seems to have to do with the use of boron, as the drop didn’t occur when boron was replaced with gallium. Something to do with a ‘boron oxygen defect’, so there’s been a lot of work done on trying to reduce the ‘concentration of oxygen impurities in the silicon wafers’, caused by the Czochralski process, the standard process for silicon wafer manufacturing. Almost all silicon solar cells are made this way. Recent research using a special imaging technique found that boron oxygen molecules converted to ‘shallow acceptors’ when exposed to light:

In essence they observed the defects transforming into little electron traps that acted as recombination sites, and thus reduced the time and probability of electrons entering the circuit to do work.

It’s something I can almost grasp. And with this knowledge, engineers, whose grasp is way firmer than mine, can find some kind of fix for the problem and get that efficiency up well beyond the 20% mark.

Jacinta: Well, this has indeed been a knowledge-expanding journey. Pour qu’une chose soit interessante, il suffit de la regarder longtemps. You mentioned the depletion layer, which caught my attention. It’s a central feature of semiconductor physics, also called depletion zone, depletion region, junction region and more. The depletion zone is so called because of the depletion of carriers in the region. Charge carriers presumably. Any rate, this region, and understanding it, is key to understanding the physics of semiconductors. The Wikipedia article on what they call the depletion region is a useful supplementary to our discussion. We might explore all this further, or not, depending on our own depletion levels…

References

The mystery flaw in solar panels  (video)

https://en.wikipedia.org/wiki/Depletion_region

 

Written by stewart henderson

September 21, 2022 at 3:18 pm

advancing solar, the photovoltaic effect, p-type semiconductors and the fiendishness of human manipulation

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how to enslave electrons – human, all too human – stolen from E4U

Canto: Back to practical stuff for now (not that integral calculus isn’t practical), and the efficiencies in solar panels among other green technologies. Listening to podcasts such as those from SGU and New Scientist while walking the dog isn’t the best idea, what with doggy distractions and noise pollution from ICEs, so we’re going to take some of the following from another blog, Neurologica, which was also summarised on a recent SGU podcast.

Jacinta: Yes it’s all about improvements in solar panels, and the materials used in them, over the past couple of decades. We’re talking about improvements in lifespan and overall efficiency, not to mention cost to the consumer. Your standard silicon solar panels have improved efficiency since the mid 2000s from around 11% to around 28% – something like a 180% improvement. Is that good maths? Anyway, it’s the cheapest form of new energy and will become cheaper. And there’s also perovskite for different solar applications, and the possibility of quantum hi-tech approaches, using advanced AI technology to sort out the most promising. So the future is virtually impossible for we mere humans to predict.

Canto: Steven Novella, high priest of the SGU and author of the Neurologica post, suggests that with all the technological focus in this field today, who knows what may turn up – ‘researchers are doing amazing things with metamaterials’. He takes a close look at organic solar cells in particular, but these could possibly be combined with silicon and perovskite in the future. Organic solar cells are made from carbon-based polymers, essentially forms of plastic, which can be printed on various substrates. They’re potentially very cheap, though their life-span is not up to the silicon crystal level. However, their flexibility will suit applications other than rooftop solar – car roofs for example. They’re also more recyclable than silicon, which kind of solves the life-span problem. Their efficiency isn’t at the silicon level either, but that of course may change with further research. Scaling up production of these flexible organic solar materials has already begun.

Jacinta: So, I’ve mentioned perovskite, and I barely know what I’m talking about. So… some basic research tells me it’s a calcium titanium oxide mineral composed of calcium titanate (chemical formula CaTiO3), though any material with the ‘perovskite structure’ can be so called. It’s found in the earth’s mantle, in some chondritic meteorites, ejected limestone deposits and in various isolated locations such as the Urals, the Kola Peninsula in Russia, and such other far-flung places as Sweden and Arkansas. But I think the key is in the crystalline structure, which can be found in a variety of compounds.

Canto: Yes, worth watching perovskite developments in the future.  I’m currently watching a video from Real Engineering called ‘the mystery flaw of solar panels’, which argues that this flaw has been analysed and solutions are being found. So, it starts with describing the problem – light-induced degradation, and explaining the photovoltaic effect:

The photovoltaic effect is the generation of voltage and electric current in a material upon exposure to light. It is a physical and chemical phenomenon.

Jacinta: Okay can we get clear again about the difference between voltage and current? I know that one is measured in volts and the other in amps but that explains nout.

Canto: Well, here’s one explanation – voltage, or emf, is the difference in electric potential between one point and another. Current is the rate of flow of an electric charge at any particular point. Check the references for more detail on that. Anyway we really are in the middle of a solar revolution, but the flaw in current solar panels is that newly manufactured solar cells are being tested at a little over 20% efficiency, that’s to say, 20% of the energy input from the sun is being converted into electric current. But within hours of operation the efficiency drops to 18% or so. That’s a 10% drop in generation, which becomes quite substantial on a large scale, with solar farms and such. So this is the problem of light-induced degradation, as mentioned. So, to quote the engineering video, ‘[the photovoltaic effect] is where photons of a particular threshold frequency, striking a material, can cause electrons to gain enough energy to free them from their atomic orbits and move freely in the material’. Semiconductors, which are sort of halfway between conductors and insulators, are the best materials for making this happen.

Jacinta: That’s strange, or counter-intuitive. Wouldn’t conductors be the best for getting electrons moving? Isn’t that why we use copper in electric wiring?

Canto: That’s a good question, which we might come back to. The first semiconducting material used, back in the 1880s, was (very expensive) selenium, which managed to create a continuous current with up to 1% efficiency. And so, silicon.

Jacinta: Which is essentially what we use, in inedible chip form, in all our electronic devices. Pretty versatile stuff. Will we always have enough of it?

Canto: Later. So when light hits this silicon crystal material, it can either be reflected, absorbed or neither – it may pass through without effect. Only absorption creates the photovoltaic effect. So, to improve efficiency we need to enhance absorption. Currently 30% of light is reflected from untreated silicon panels. If this wasn’t improved, maximum efficiency could only reach 70%. So we treat the panels with a layer of silicon monoxide reducing reflection to 10%. Add to that a layer of titanium dioxide, taking reflection to as low as 3%. A textured surface further enhances light absorption – for example light might be reflected sideways and hit another bump, where it’s absorbed. Very clever. But even absorbed light only has the potential to bring about the photovoltaic effect.

Jacinta: Yes, in order to create the effect, that is, to get electrons shifted, the photon has to be above a certain energy level, which is interesting, as photons aren’t considered to have mass, at least not when they’re at rest, but I’m not sure if photons ever rest… As the video says, ‘a photon’s energy is defined by multiplying Planck’s constant by its frequency’. That’s E = h.f, where h is Planck’s constant, which has been worked out by illustrious predecessors as 6.62607015 × 10−34 joule-seconds, according to the International System of Units (SI). And with silicon, the photons need an electromotive force of 1.1 electron volts to produce the photovoltaic effect, which can be converted, apparently, to a wavelength of 1,110 nanometres. That’s in the infrared, on the electromagnetic spectrum, near visible light. Any lower, in terms of energy (the lower the energy, the lower the frequency, the longer the wavelength, I believe), will just create heat and little light, a bit like my brain.

Canto: I couldn’t possibly comment on that, but the video goes on to explain that the solar energy we get from the sun, shown on a graph, is partially absorbed  by our atmosphere before it reaches our panels. About 4% of the energy reaching us is in the ultraviolet, 44% is in the visible spectrum and 52% is in the infrared, surprisingly enough. Infrared red light has lower energy than visible light but it has a wider spectrum so the total energy emitted is greater. Now, silicon cannot use light above 1,110 nms in wavelength, meaning that some 19% of the sun’s energy can’t be used by our panels.

Jacinta: Yes, and another thing we’re supposed to note is that higher energy light doesn’t release more electrons, just higher energy electrons…

Canto: And presumably they’re talking about the electrons in the silicon structure?

Jacinta: Uhh, must be? So blue light – that’s at the short-wavelength end of the visible spectrum – blue light has about twice the energy of red light, ‘but the electrons that blue light releases simply lose their extra energy in the form of heat, producing no extra electricity. This energy loss results in about 33% of sunlight’s energy being lost.’ So add that 33% to the 19% lost at the long-wavelength end, that’s 52% of potential energy being lost. These are described as ‘spectrum losses’.

Canto: Which all sounds bad, but silicon, or its reaction with photons, has a threshold frequency that ‘balances these two frequency losses’. So, it captures enough of the low-energy wavelengths (the long wavelengths beyond the infra-red), while not losing too much efficiency due to heat. The heat problem can be serious, though, requiring active cooling in some climates, thus reducing efficiency in a vicious circle of sorts. Still, silicon is the best of threshold materials we have, presumably.

Jacinta: So, onto the next piece of physics, which is that there’s more to creating an electric current than knocking an electron free from its place in ye olde lattice, or whatever. For starters, ye olde electron just floats about like a lost lamb.

Canto: No use to anyone.

Jacinta: Yeah, it needs to be forced into doing work for us.

Canto: Because humans are arseholes who make slaves of everything that moves. Free the electrons!

Jacinta: You’ve got it. They need to be forced to work an electric circuit. And interestingly, the hole left when we’ve knocked an electron out of its happy home, that hole is also let loose to roam about like a lost thing. Free electrons, free holes, when they meet, they’re happy but the circuit is dead before it starts.

Canto: This sounds like a tragicomedy.

Jacinta: So we have to reduce the opportunities for electrons and holes to meet. Such is the cruelty of progress. For of course, we must needs use force, taking advantage of silicon’s unique properties. The most excellent crystal structure of the element is due to its having 4 electrons in its outer shell. So it bonds covalently with 4 other silicon atoms. And each of those bonds with 3 others and so on. A very stable balance. So the trick that we manipulative humans use to mess up this divine balance is to introduce impurities called dopants into the mix. If we add boron, which has 3 outer electrons, into the crystal lattice, this creates 3 covalent bonds with silicon, leaving – a hole!

Canto: How fiendishly clever!

Jacinta: It’s called a p-type trick, as it has this ‘positive’ hole just waiting for an electron to fill it. Sounds kind of sexy really.

Canto: Manipulation can be sexy in a perverse way. Stockholm syndrome for electrons?

Jacinta: Okay, there’s a lot more to this, but we’ve gone on long enough. I’ve had complaints that our blog posts are too long. Well, one complaint, because only one or two people read our stuff…

Canto: No matter – at least we’ve learned something. Let’s continue to rise above ourselves and grasp the world!

Jacinta: Okay, to be continued….

References

Organic Solar Cells and Other Solar Advances

https://www.theskepticsguide.org/podcasts

https://news.mit.edu/2022/perovskites-solar-cells-explained-0715

The Mystery Flaw of Solar Panels (Real Engineering video)

https://byjus.com/physics/difference-between-voltage-and-current/

Written by stewart henderson

September 18, 2022 at 8:12 pm

an interminable conversation 9: some basic physics

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yer most basic sine graph

Jacinta: So it’s time for us oldies to go to school, and get into physics from scratch, including the maths.

Canto: Yes, we’re not going to go all historical this time, much as we love all the nerdy characters to be encountered, instead we’re going to go with the concepts, from simple to complicated. I’ve found a collection of videos, called ‘crash course physics’, and we’re going to follow the ineffable logic of the presenter, Dr Shini Somara, to reach the pinnacle of sagesse en physique. Starting with basic motion in a straight line.

Jacinta: Exciting. I’ve done that. But in this first episode she deals with cars and acceleration, inter alia, including its maths. Equations! Time, position, velocity and acceleration will be explained/analysed in simple terms for this starter.

Canto: Kinematic equations – we’re going to the Kinema! So, motion in one direction on a straight line. You’re stopped at a red light, and then put your foot on the accelerator when it goes green. Seven seconds later (precisely), there’s a siren behind you – a police car is asking you to stop. They give you a ticket for speeding in a 100kph zone.

Jacinta: So, in 7 seconds you’re up to more than 100kph? I know nothing about cars but that’s unusual? Is it?

Canto: I’m sure car nerds can tell us, but so can google. There are plenty of cars that can get to 100 in less than 4 secs, even less than 3. Supposedly. Anyway, you’re doubtful about the police claim, but you can’t be sure, your speedometer is stuffed. How can you challenge the police claim, using maths?

Jacinta: You can’t, and anyway in Australia you’d be defected for a stuffed speedo.

Canto: But this is the USA, the land of shitty libertarian laws. So you’re travelling in one direction, one-dimensionally, so to speak. So the key variables here are the afore-mentioned time, position, velocity and acceleration. We also have to bear in mind change in position, aka displacement, which could have a positive or negative value – in this example, clearly positive. Now, velocity is about how that displacement occurs over time. It also can have a positive or negative value. Acceleration is about changes in velocity over time. You can feel that change – positive or negative – when you’re ‘thrown’ forward or backward on acceleration or braking.

Jacinta: So Dr Somara presents graphs that are fairly easy to read for a stationary vehicle, and one moving at a constant velocity. The vertical x-axis measures position or displacement in metres from an initial position, the y axis measures time. A stationary vehicle will show a straight horizontal line from the moment it stopped until it starts to move again. Constant velocity will show a straight line moving diagonally along both axes. An accelerating vehicle will of course show a curving line, curving up to the vertical, while a decelerating one will be curving to the horizontal.

Canto: So that’s a simple position v time graph, now to look at velocity and acceleration slightly differently, with velocity in metres/second on the vertical axis and time on the horizontal, and with acceleration in metres per second per second, that is, metres per second squared, on the vertical axis, and time, in seconds, on the horizontal. So this relates all our variables, time, position, velocity and acceleration. Average velocity is the change in position over time, and acceleration is the change in velocity over time. To get average velocity you divide change in position by change in time. 

Jacinta: But as Dr Somara says, subtraction is also a feature – to find out ‘change’ you subtract initial value from final value, which sounds right but somehow seems to contradict the previous….

Canto: One’s talking about a change, the other about an average. They’re quite different. So the change in a particular value, or variable, is symbolised or abbreviated as delta, ∆. So, v = ∆x/∆t, average velocity (the v should have a bar above it, but I haven’t learned how to do that – will I need an extra keyboard?) equals change in position over change in time. For Dr Somari’s example, the car moved from 4 metres to 13 metres (the change in position), i.e. a value of 9 metres for ∆x. This occurred over 3 seconds, apparently, which divides as 3m/sec for average velocity over that period. But of course the car was accelerating during that period. The equation for acceleration is a = ∆v/∆t, for average acceleration.

Jacinta: Okay, and we can, apparently handily, rearrange the equation to get v(average) = v(at time zero) + at. This equation is called the Definition of Acceleration. Tadaaa! Constant acceleration is equal to the change in velocity divided by change in time. This is the first of the two main kinematic equations, which links velocity acceleration and time.

Canto: Okay now our physicist turns to gravity (g), which here on Earth is a force causing acceleration at 9.81 m/sec squared. But then she talks about the second kinematic equation, the Displacement Curve, which involves acceleration, starting velocity and time in order to calculate displacement:

x(position) – x(at time zero, initial position) = v(initial velocity)t +1/2a(acceleration)t(squared).

All of which looks very messy because I haven’t learned how to do the proper notation. Anyway this links acceleration as change in velocity to velocity as change in position. Right?

Jacinta: Uhhh, yeah. And the other kinematic equations, we’re assured, are just rearrangements of this dynamic duo. So apparently this takes us back to our speeding issue at the start. The initial velocity was 0, the time was 7 seconds. The displacement curve²equation/formula can be used to work it all out, or at least the acceleration. Our physicist tells that x – x (initial position) is 122 metres, which equals initial velocity (zero) multiplied by 7 seconds (which must surely be zero?)  plus I/2a (which is to be found) multiplied by 7s squared, which is 49 seconds. So 122m = 0 + 49 (49) multiplied by half the acceleration, which by calculation I discovered to be close to 2.5, so the acceleration was approximately 5 metres per second squared.

Canto: It works out! And, following our expert, we can use the Definition of Acceleration formula to arrive at final velocity. It’s basically V + at, or 0 + 5 X 7, so a speed of 35 m/sec, which in km terms is about 126 km/h. Amazing! We got the maths. There is hope!

Jacinta: Well they’re diving into the deep end with crash course physics, as the next video is all about calculus and derivatives. About which I have no idea.

Canto: Yes, maths are the basis of physics, and we lost contact with complex maths decades, though I’m quite good at multiplication. But calculus, duh. Though our teacher tells us that it’s all just about accurately describing change.

Jacinta: Important – she goes on to explain things called derivatives, but I note in the inset:

Not all equations have derivatives! When we say ‘equations’ here, we really mean a function – an equation with only one output for each input. More specifically, we’re talking about functions that have derivatives.

I’m looking forward to clarification of all that.

Canto: So calculus explains the why’s and wherefores of change through derivatives. She also mentions integrals early on, as ways of calculating area under a curve – which we actually mentioned in those terms in a previous post.

Jacinta: We sound smart sometimes. So, derivatives. Dr Somara returns to the car and speeding example. The car drives off after the police incident, accelerating of course. But we don’t have a direct measure of the acceleration, but we know positional change over time. This is apparently equal to amount of time driving, squared, X = t².  After 20 secs of driving, some kind of roadside ‘detector’ reveals the car’s speed. The driver takes time to register that she’s going even faster than 126 mph.

Canto: Dumb blond? Maybe not, maybe the detector is dodgy. How to find the velocity at the moment she passes it? Which, according to Dr Somara is the derivative of her change in position. And this is also about limits. These are key ideas:

Limits are based on the idea that if you have an equation on a graph, you can often predict what it’s going to look like at one point, just by knowing what it looks like at the surrounding points.

Jacinta: So our teacher gives the example of graphing x = t² when t approaches the limit of 0. So remember we have our time on the horizontal, and distance covered (or displacement, or positional change – it seems ‘distance’ is a no-no in this maths) on the vertical axis. So, moving back to zero from t=1 and x=1 she finds that when t=0.5, x=0.25, and when t reaches 0.1, x=0.001, so both values approach zero. This apparently shows what happens when you make intervals smaller. Another definition:

An interval is just a range on a graph. It’s the space between two points on the horizontal axis.

Of course, because that’s the time axis, generally. This is great parroting, but then when parrots copy their trainer perfectly they’re regarded as brilliant.

Canto: So we’re calculating the average velocity over a particular interval – from 15 to 20 secs. We use the equation v = ∆x/∆t (∆x is change in position, ∆t is change in time). The change in position, after subtraction, was 175 metres, the change in time 5 secs. So the average velocity works out as 35 m/sec. But this is only an average, and doesn’t take into account acceleration. But using limits gets us closer to the number we want. You can calculate your average over increasingly small intervals to arrive at an increasingly accurate figure.

Jacinta: So, sticking with our teacher, velocity is an equation that describes change in position, acceleration describes change in velocity. Velocity is thus the derivative of position and acceleration is the derivative of velocity. This is expressed in writing, using, for example, the power rule, expressed using variables and their numbered exponents. So x = t² is an equation that works here. To calculate the derivative, you take the exponent, 2, and put it in front of the variable, and subtract 1 from the exponent, and that’s the derivative, 2t. In full, the derivative of x = t² is 2t.

Canto: That’s a trick, as Dr Somara said, but it’s not really explained. She says ‘no matter how [you’re accelerating], your velocity will be 2t – double the number of seconds’. So I think it depends on those seconds. After 5 seconds, say, you’re travelling at 5m/sec, but after 20 secs, your speed is 40m/sec. So dx/dt = 2t ‘which is just a way of saying, mathematically, we’re taking the derivative of x with respect to t’. But it’s also written differently sometimes: if f(t) = t², then f'(t) = 2t. And I’m guessing that f stands for function, but I don’t quite know what a function is.

Jacinta: A function is:

in mathematics, an expression, rule, or law that defines a relationship between one variable (the independent variable) and another variable (the dependent variable). Functions are ubiquitous in mathematics and are essential for formulating physical relationships in the sciences.

That’s from Britannica online. So to continue, if f(t) = t², then f'(t) = 2t. That’s to say, f prime (t) = 2t, according to our teacher, who doesn’t explain ‘prime’. Do we have to do a maths course before we do this physics course? Does it have to do with prime numbers?

Canto: Apparently not. The symbol can serve a number of purposes in maths. Let’s just leave it for now. Using the power rule we can find other derivatives, e.g. x = 7t to-the-power-6. This equation has the variable t, and its exponent 6. We take the exponent and put it in front of the 7t variable, multiplying the number and subtracting 1 from the exponent, 42t to-the power 5. That’s to say dx/dt = 42(t to the power of 5). But maybe that shouldn’t be bracketed. And when the exponent is a fraction or decimal, the derivative of, say t to the power of one half is 1/2t to the negative one half. You always minus one, I don’t know why.

Jacinta: Ours is clearly not to reason why, at least not yet. This derivative trick works for negatives too. In the case of x = t to-minus-2, the derivative (dx/dt) = -2t to minus 3. Not very comprehensible, and then she mentions the dread word, trigonometry, used for calculating triangles, their angles and sides. Apparently physics uses right-angled triangles a lot. We shall see.

Canto: Indeed, let’s get into it. The derivatives of sine x and cosine x. If you have a right-angled triangle with an adjacent angle x, sin(x) = the length of the opposite side divided by the hypotenuse. For cosine, cos(x) it’s the length of the adjacent side divided by the hypotenuse. So, sin(x) = o/h, cos(x) = a/h. ‘So the graphs will tell you what those ratios will be, depending on the angle’.

Jacinta: I’m not sure if I really understand this, but let’s move on into further weird territory, in which sin(x) is plotted on a graph going from -360° to 360° on the x (horizontal) axis (that’s the ‘phase’, in degrees) and -1 to 1 on the y axis. At x = -90° and x = 90° the curve turns – that’s at every 180°. At those points the equations aren’t changing and the derivative is zero. Between the points the derivative oscillates from positive to negative. That derivative is in fact cos(x). I’m not sure why, but the derivative of cos(x) is -sin(x), the derivative of -sin(x) is -cos(x) and the derivative of -cos(x) is sin(x), for future reference. I’m hoping it’ll all become clear some day. Graphing all these will provide the proofs, evidently.

Canto: Yes, so Dr Somara finishes off this vid with another derivative that’s important in calculus, e×, the derivative of which is also e×, always. e, like π, is an irrational number which is quite vital to calculus, apparently. And even finance. Can’t wait to find out. So with the preceding we can, supposedly, take any equation for position and calculate the derivative, and so, velocity. And for velocity, your acceleration. Using integrals, which we’ll soon learn about, we can go backwards from acceleration to velocity, and from velocity to position. Presumably that will be next time.

Jacinta: So easy…

References

 

Written by stewart henderson

September 14, 2022 at 8:05 am

an interminable conversation 8: eddy currents, Ampere’s Law and other physics struggles

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easy peasy

Canto: So we were talking about eddy currents, but before we get there, I’d like to note that, according to one of the various videos I’ve viewed recently, this connection between electricity and magnetism, first observed by Faraday and Henry, and brilliantly mathematised by James Clerk Maxwell, has transformed our human world perhaps more than any other discovery in our history. I think this is why I’m really keen to comprehend it more thoroughly before I die.

Jacinta: Yeah very touching. So what about eddy currents?

Canto: Okay, back to Wikipedia:

Eddy currents (also called Foucault’s currents) are loops of electrical current induced within conductors by a changing magnetic field in the conductor according to Faraday’s law of induction or by the relative motion of a conductor in a magnetic field. Eddy currents flow in closed loops within conductors, in planes perpendicular to the magnetic field. They can be induced within nearby stationary conductors by a time-varying magnetic field created by an AC electromagnet or transformer, for example, or by relative motion between a magnet and a nearby conductor.

Jacinta: Right. All is clear. End of post?

Canto: Well, this ‘perpendicular’ thing has been often referred to. I’ll steal this Wikipedia diagram, and try to explain it in my own words.

So, the eddy currents are drawn in red. They’re induced in a metal plate (C)…

Jacinta: What does induced actually mean?

Canto: That’s actually quite a difficult one. Most of the definitions of electrical induction I’ve encountered appear to be vague if not circular. Basically, it just means ‘created’ or ‘produced’.

Jacinta: Right. So, magic?

Canto: The fact that an electric current can be produced (say in a conductive wire like copper) by the movement of a magnet suggests strongly that magnetism and electricity are counterparts. That’s the central point. That’s why we refer to electromagnetism, and electromagnetic theory, because the connections – between the conductivity and resistance of the wire and the strength and movement of the magnet (for example it can be made to spin) will determine the strength of the electric field, or the emf, and all this can be calculated precisely via an equation or set of equations, which helps us to use the emf to create useful energy.

Jacinta: Okay, so this metal plate is moving, and I’m guessing V stands for velocity. The plate is a conductor, and the nearby magnet (N – that’s the magnet’s north pole) produces, or induces, a magnetic field (B) – or it just has a magnetic field, being a magnet, and this creates a current in the plate.

Canto: Which is perpendicular to the magnetic field, because what causes the current in the plate is the movement of electrons, which can’t jump out of the plate after all, but move within the plane of the plate. And the same would go for a wire. There’s also the matter of the direction, within the plane, of the current – clockwise or anticlockwise? And many other things beyond my understanding.

Jacinta: Would it help to try for a historical account, going back to the 18th century – Franklin, Cavendish, even Newton? The beginning of the proper mathematisation of physical forces? I mean, all I wanted to know was how an induction stovetop worked.

Canto: That’s life – you wonder why x does y and you end up reflecting on the origin of the universe. I’ve looked at a couple of videos, and they explain well enough what happens when a magnet goes inside an electrified coil, but never really explain why. But let’s just start with Faraday. He was a great experimenter, as they all tell me, but not too much of a mathematician. Faraday wasn’t the first to connect electricity with magnetism, though. H C Ørsted was the first, I think, to announce, and presumably to discover, that an electric current flowing through a wire produced a magnetic field around it. That was around 1820, which dates the first recognised connection between electricity and magnetism. The discovery was drawn to the attention of Andre-Marie Ampère, who began experimenting with, and mathematising, the relationship. Here’s a quote from Britannica online:

Extending Ørsted’s experimental work, Ampère showed that two parallel wires carrying electric currents repel or attract each other, depending on whether the currents flow in the same or opposite directions, respectively. He also applied mathematics in generalizing physical laws from these experimental results. Most important was the principle that came to be called Ampère’s law, which states that the mutual action of two lengths of current-carrying wire is proportional to their lengths and to the intensities of their currents.

Jacinta: That’s interesting – what does the mutual action mean? So we have two lengths of wire, which could be flowing in the same direction, in which case – what? Do they attract or repel? Presumably they repel, as like charges repel. But that’s magnetism, not electricity. But it’s both, as they were starting to discover. But how, proportional to the lengths of the wire? I can imagine that the intensity of the currents would be proportional to the degree of attraction or repulsion – but the length of the wires?

 

Canto: You want more bamboozlement? Here’s another version of Ampère’s law:

The integral around a closed path of the component of the magnetic field tangent to the direction of the path equals μ0 times the current intercepted by the area within the path.

\int \mathrm{B} \cdot \mathrm{d} \mathrm{l}=\mu_{o} I
Jacinta: Right. Why didn’t you say that before? Seriously, though, I do want to know what an integral is. I’m guessing that ‘tangent to’ means ‘perpendicular to’?
Canto: Not quite. Forget the above definition, though it’s not wrong. Here’s another definition:
The magnetic field created by an electric current is proportional to the size of that electric current with a constant of proportionality equal to the permeability of free space.
Jacinta: No, sorry, that’s  meaningless to me, especially the last bit.

Canto: The symbol in in the equation above, (μ0), is a physical constant used in electromagnetism. It refers to the permeability of free space. My guess is that it wasn’t defined that way by Ampère.

Jacinta: I understand precisely nothing about that equation. Please tell me what an integral is, as if that might provide enlightenment.

Canto: It’s about quantifying areas defined by or under curves. And a tangent – but let’s not get into the maths.

Jacinta: But we have to!

Canto: Well, briefly for now, a tangent in maths can sort of mean more than one thing, I think. If you picture a circle, a tangent is a straight line that touches once the circumference of the circle. So that straight line could be horizontal, vertical or anything in between.

Jacinta: Right. And how does that relate to electromagnetism?

Canto: Okay, let’s return to Ampère’s experiment. Two parallel wires attracted each other when their currents were running in the same direction, and repelled each other when they were running in the opposite direction. It’s also the case – and I don’t know if this was discovered by Ampère, but never mind – that if you coil up a wire (carrying a current), the inside of the coil acts like a magnet, with a north and south pole. Essentially, what is happening is that the current in a wire creates a magnetic field around it, circling in a particular direction – either clockwise or anti-clockwise. The magnetic field is ‘stronger’ the closer it is to the wire. So there’s clearly a relationship between distance from the wire and field strength. And there’s also a relationship between field strength and the strength of the current in the wire. It’s those relations, which obviously can be mathematised, that are the basis of Ampère’s Law. So here’s another definition – hopefully one easier to follow:

The equation for Ampère’s Law applies to any kind of loop, not just a circle, surrounding a current, no matter how many wires there are, or how they’re arranged or shaped. The law is valid as long as the current is constant.

That’s the easy part, and then there’s the equation, which I’ll repeat here, and try to explain:

\int \mathrm{B} \cdot \mathrm{d} \mathrm{l}=\mu_{o} I
So, that first symbol represents the integral, and B is the magnetic field. Remember that the integral is about the area of a ‘loop’, so the area of B, multiplied by the cosine of theta (don’t ask) with respect to distance (d), is equal to a constant, (μ0), multiplied by the current in the loop (I).
Jacinta: Hmmm, I’m almost getting it, but I’ve never really met trigonometry.
Canto: Well the video I’m taking this from simplifies it, perhaps: ‘the total magnetic field along the loop is equal to the current running through the loop times a constant number’. So, it’s an equation of proportionality, I think. And the constant – mu0, aka the magnetic constant – has a numerical value which I won’t spell out here, but it involves pi and newtons per amps squared.
Jacinta: So you’ve used a ‘crash course physics’ video for the last part of this conversation, which is useful, but assumes a lot of knowledge. Looks like we may have to start those videos almost from the beginning, and learn about trickonometry, and integers, and so much els
Canto: ……..
References
https://web.iit.edu/sites/web/files/departments/academic-affairs/academic-resource-center/pdfs/Amperes_law.pdf
https://en.wikipedia.org/wiki/Integral
https://www.sciencefacts.net/amperes-law.html

Written by stewart henderson

August 30, 2022 at 7:56 pm

an interminable conversation 7: East Turkestan and the question of genocide

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the uneasy life…

Canto: So several years ago I was invited, sort of, to take over an English class for NESB students at Wandana Community Community Centre in Gilles Plains, a north-eastern suburb of Adelaide, here in sleepy South Australia. Some of the students had been coming to my class in the city, because they were unhappy with their then teacher at Wandana. My city class had people of all ages, from 16 to 60, Indians, Africans and Europeans. The Wandana group was always women, of Middle Eastern appearance, most but not all wearing hijabs. So I accepted this offer, and found myself in the pleasant company of a lively group of women, many of them young mothers taking advantage of the community centre’s creche facilities. During introductions I asked about their native countries. There were a couple of Iraqis (Kurds in fact), one Afghani, and a large number of women from East Turkestan, a country I’d never heard of. I’d heard a bit about the ‘Stans’, but other than Pakistan and Afghanistan I wasn’t sure of any other names or locations…

Jacinta: East Turkestan is their name for Xinjiang Province in north-west China.

Canto: You’re spoiling my story. I just accepted that there was a country called East Turkestan, and that these women were Muslim, and seemed to know each other well, and liked to ask political questions and engage in argument, and seemed to amusingly dominate their husbands who came to pick them up after class. I became friendly with the centre’s social worker, also from East Turkestan. She it was who ‘recruited’ me to Wandana. She spoke perfect English, and filled me in on the East Turkestan story. The region was, as you know, called Xinjiang Province by the Chinese, and had been part of China for some time, but its inhabitants were clearly not Han Chinese, and saw themselves as completely separate as a people, if not as a nation. So I was intrigued, but just accepted it as one of the anomalies of cultures and nations…

Jacinta: Like the non-existent but presumably real Kurdistan?

Canto: Precisely…

Jacinta: Life is weirdly unfair like that, when you have cultures or language groups that would make sense as properly official nations, with their recognised boundaries, their vote at the UN, their good or bad governments, and then you’ve got made-up nations, created by exterior forces, like Afghanistan, and dozens of African nations decided at the Berlin Conference of 1884-5 or the Balkan and other states at the Other Berlin Conference of 1878, or was it the other way around?

Canto: Yes, nations are often such arbitrary creations and then their inhabitants get all nationalistic and xenophobic and irrational about ‘their’ piece of land. Anyway, my thoughts on East Turkestan took a different turn when the social worker asked me to help write a letter to the Federal Immigration Minister regarding her brother, an Australian citizen who had returned to his native region for a holiday and had ended up in prison in Kazakhstan, across the border from Xinjiang. I was assured that he had done nothing wrong, but I couldn’t get any more details apart from the claim that Uyghurs (she didn’t use this term, which I didn’t know about until after I’d left Wandana) were being arbitrarily imprisoned in the province, and if they fled to Kazakhstan they were also in danger, due to dodgy dealings between that country and China. Anyway, I left for more lucrative pastures shortly afterwards, but I very much doubt that our letter had the required result.

Jacinta: That Adelaide suburb, Gilles Plains, apparently houses the largest Uyghur community in Australia.

Canto: Yes, and since I left Wandana, more than a decade ago, the oppression of the Uyghur people has worsened – or maybe I just know more about it. It seems their region was kind of in the way of the Belt and Road project, and/or some of the population there were getting uppity about autonomy, and certainly not conforming to a one-China ideology, so the Party started getting aggressive, which bred more Uyghur violence, which led to mass disappearances and ‘re-education camps’ and some talk about using them as fields for harvesting organs.

Jacinta: Yes, these claims have been aired for years, and of course strenuously denied by the Party, though a paper was quite recently published in the American Journal of Transplantation(!), entitled ‘Execution by organ procurement: Breaching the dead donor rule in China’, which purports to find evidence of such things, though as far as I can see, no evidence is provided as to specific ‘donors’.

Canto: So all of this Uyghur stuff has been brought back to mind by my reading of the book China Panic, by David Brophy, a historian of Uyghur nationalism and a senior lecturer in modern Chinese history at Sydney University. Chapter 6 of the book is called ‘Human rights and Xinjiang’, and it provides much interesting and sobering background info. It seems that the Uyghurs, and Muslims in general (not all Uyghurs are Muslim), have become the Party’s new villains, replacing the Falon Gong of recent years. Promoting their faith to their fellows can elicit a hefty prison sentence. As with the Party’s treatment of Tibetans, but more so, Uyghurs’ visible and behavioural differences from bog-standard Han-ness are seen as a security threat. They’re also stigmatised as ‘backward’, hence the re-education gimmick, which taps into the standard racism that will be familiar to Australians who know our history of stealing indigenous children and providing them with a proper Christian education. With the USA still under the influence of the post-September 11 ‘war on terror’ it was hard to garner too much sympathy for the Uyghurs from that country and its allies, including Australia, but the lack of response, and worse, from Muslim countries has been disappointing, to say the least. Here’s how Brophy puts it:

In fact, at the most recent meeting of foreign ministers of the Organisation of Islamic Co-operation, they went so far as to ‘commend the efforts of the People’s Republic of China in providing care to its Muslim citizens’ – an appalling stance.

It seems that some of these countries had their own problems with minorities, and felt that crack-downs in the name of ‘national solidarity’ were justified – and of course there’s the question of valuable financial ties with China. And there was also just plain ignorance about Uyghur identity, at least early on.

Jacinta: Well, think of the Palestinians – it seems nobody is on their side, certainly on a national level, outside the Middle East.

Canto: Well, I’ve read at least two books by Palestinians about their history and their plight. And there are pro-Palestinian movements and groups, here in Australia and elsewhere, but the Uyghurs don’t have that profile…

Jacinta: I bet they have some articulate spokespeople and writers…

Canto: They’d have to be outside China. But that’s worth exploring. Anyway, Wikipedia has an article, Uyghur genocide, which says it straight, and makes for sickening reading.

Jacinta: So what is to be done?

Canto: The big question. China under The Party is, unsurprisingly, more than reluctant to sign up to any human rights conventions. As Wikipedia puts it: 

In December 2020, a case brought to the International Criminal Court was dismissed because the crimes alleged appeared to have been “committed solely by nationals of China within the territory of China, a State which is not a party to the [Rome Statute of the ICC]”, meaning the ICC couldn’t investigate them.

The lack of public awareness and sympathy for these people, who could be described as just as in thrall to their religion as many United Staters are to theirs, might also be due to the lingering ‘war on terror’, and the consequent anti-Muslim prejudices evident here in Australia as elsewhere. All we can do here is highlight the plight of these people, and counteract propaganda against them, which is going on here, courtesy of Chinese pamphleteers, young people who I suspect know nothing about the real situation.

Jacinta: That’s an important point. A recent study found that the Chinese have far more faith in their government than, for example, Russians have faith in theirs. I presume that’s because Russians are more connected to the WEIRD world than the Chinese, most of whom have never at any time sniffed the chance of getting out from under paternalistic fascism. Their media has been far more controlled for far longer. Though still, there is hope from expat Chinese, and even temporary residents, students who express love for being in a ‘freedom country’, if only for a few years.

Canto: Well, you may have gotten this idea about China’s faith in their government and its media from the Skeptics’ Guide to the Universe, episode 893, in which, in its science or fiction section, Steve Novella trumped most of the Rogues with the item – ‘Reported trust in the media in 2021 was highest in China at 80%, and lowest in Russia at 29%, with the US in between at 39%’, which turned out to be ‘science’. As Novella pointed out, this was reported trust. It may well be that the Chinese population, after what they’d been through with Mao and the Tiananmen crack-down, and now with their latest thug, wouldn’t dare to stand up against the ubiquity of state media.

Jacinta: So it’s up to outsiders to speak up, and to encourage Uyghur expats to speak up, to allow them a voice and provide a listening ear and a sense of due outrage at the horrors being inflicted upon them.

References

David Brophy, China panic: Australia’s alternative to paranoia and pandering, 2021

https://en.wikipedia.org/wiki/Uyghurs

https://www.theskepticsguide.org/podcasts (ep 893)

Written by stewart henderson

August 29, 2022 at 8:54 pm

An interminable conversation 6: trying to understand inductive cooking.

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the guts of an induction cooker, I believe

Canto: So, with all the fuss and excitement about renewables, we should continue the near impossible task of trying to get our heads around electricity, never mind renewable sources of electricity. It’s still electrickery to me. For example, Saul Griffith in The Big Switch recommends inductive electric stoves as a replacement for gas, which many swear by because they appear to heat your pot immediately, or at least very quickly compared to those old ring electric heaters…

Jacinta: Yes, but as Griffith says in that book, you can tell the gas isn’t too efficient because you feel yourself getting hot when you’re near the stove. That’s heat that isn’t going into the pot. Apparently that doesn’t happen with inductive electricity, which heats the pot just as rapidly if not more so, but almost nothing’s ‘wasted’ into the surrounding air.

Canto: Unless you like to feel toasty warm in the kitchen. Anyway we’re talking about induction cooktops,to give them their proper name, apparently. The old electric cooktops had those coils, and they’re what we grew up with. Here’s a summary from the Forbes website:

Also known as radiant cooktops, electric cooktops offer centralized heat. Electric cooktops have an electrical current that flows through a metal coil underneath the glass or ceramic surface. The coil becomes hot and starts glowing due to the electrical resistance. It will transfer its heat through the glass using infrared energy. This means the burner holding your pot or pan is the one that gets hot. Your food is then cooked by the transfer of heat between the cooktop and the pot. There is residual heat for an undetermined amount of time with electric cooktops, which is why these ranges tend to have an indicator light letting you know that the burner is still warm.

Jacinta: Metal coils under glass or ceramics…? As I recall, they were just coils, not under anything. They were grey. But maybe they were ceramic, with metal embedded within, or on the underside. I wish I was the type who pulled things apart to see how they worked, like geeky kids. And wtf is ‘infrared energy’? As far as I remember, the coils turned visible red when hot, not invisible infrared.

Canto: You see the red light but you feel the infrared heat. The heat you feel from the sun is in the non-visible part of the spectrum – the infrared and beyond. On the other side of the visible spectrum is the ultraviolet and beyond. I think.

Jacinta: So which side has the long wavelengths and which side has the short? – not that this would mean much to me.

Canto: Infrared radiation is about longer wavelength, lower frequency waves than visible light, and ultraviolet radiation is higher frequency and shorter wavelengths. So they bookend invisible light, if you will. But the longest wavelength, lowest frequency waves are radio waves, followed by microwaves, while the highest frequency, shortest wavelength radiation is gamma rays. Whether there are forms of radiation beyond these ends of the spectrum, I don’t know.

Jacinta: I’ve heard of gravitational waves, which were only detected recently. What about them?

Canto: They can have almost infinitely long wavelengths apparently. So to speak. Obviously if they were ‘infinitely’ long, if that’s even meaningful, they’d be undetectable. But let’s get back down to earth, and the most useful energy. Here’s how the Red Energy website describes induction cooktops:

Basically, a standard electric or gas cooktop transfers heat (or conducts heat) from the cooktop to the pot or pan. Whereas, an induction cooktop ‘switches on’ an electromagnetic field when it comes into contact with your pot or pan (as long as the cookware contains a ferrous material like iron or steel). The heat comes on fast and instantly starts cooking the contents.

Jacinta: Okay that explains nothing much, as I don’t know, really, how an electromagnetic field works (still stupid after all these years). As to ferrous cookware, I didn’t realise you could use anything else.

Canto: Well the same website says that, given the speed of heating, you might need to upgrade to cookware that can take the stress, so to speak. As to the electromagnetic field thing, Red Energy doesn’t really explain it, but the key is that an electromagnetic field doesn’t require the heating of an element – those coily things.

Jacinta: They’ve eliminated the middle man, metaphorically speaking? I’m all in for eliminating men, even metaphorically.

Canto: Thanks. So I’m trying to get my head around this. I need to delve further into the meaning of this magical, presumably infrared, heat. The essential term to explore is electromagnetic induction, and then to join that understanding to the practical aspects, yer everyday cooking. So this goes back to the working-class hero Michael Faraday, and the Scottish hero J C Maxwell, which will be fun, though of course I’m not at all nationalistic, but…

Jacinta: Canto isn’t a particularly Scottish name is it?

Canto: My real name is Camran Ciogach Ceannaideach, but I prefer a simpler life. Anyway electromagnetic induction has a great variety of applications, but this is the ultimate, i.e Wikipedia, definition:

Electromagnetic or magnetic induction is the production of an electromotive force across an electrical conductor in a changing magnetic field.

Jacinta: None the wiser. What’s an electromotive force?

Canto: Called emf, it’s ‘the electrical action produced by a non-electrical source, measured in volts’. That’s also Wikipedia. So a non-electrical source might be a battery (which is all about chemistry) or a generator (all about steam in industrial revolution days -creating mechanical energy).

Jacinta: So the infernal combustion engine somehow converts petrol into mechanical energy? How does that happen?

Canto: Off topic. This is really difficult stuff. Here’s another Wikipedia quote which might take us somewhere:

In electromagnetic induction, emf can be defined around a closed loop of conductor as the electromagnetic work that would be done on an electric charge (an electron in this instance) if it travels once around the loop.

Jacinta: Right, now everything’s clear. But seriously, all I want to know is how to get rid of that middle man. We were talking abut cooking, remember?

Canto: So emf is also called voltage, or measured in volts, which I seem to recall learning before. Anyway, nowadays electromagnetic induction is everywhere – for example that’s how money gets removed from your bank account when you connect those cards in your wallet to those machines in the shop.

Jacinta: So they’re zapping your card, sort of?

Canto: I’ve looked at a few sites dealing with electromagnetic induction, and they all give me the same feel, that it’s like weird magic. I suppose because they explain how it works but not why.

Jacinta: Shut up and calculate?

Canto: Anyway, induction cooking has been around for more than a century, but it’s really catching on now. They always say it’s more direct, because it doesn’t involve heating an element.

Jacinta: Don’t you know it’s magic?

Canto: No, it’s magnetic. Which explains nothing. But let me try another website, this time Frigidaire:

Induction cooktops heat pots and pans directly, instead of using an electric or gas-heated element. It boils water up to 50 percent faster than gas or electric, and maintains a consistent and precise temperature. The surface stays relatively cool so spills, splatters and occasional boil-overs don’t burn onto the cooktop, making clean-up quick and easy…. Induction cooking uses electric currents to directly heat pots and pans through magnetic induction. Instead of using thermal conduction (a gas or electric element transferring heat from a burner to a pot or pan), induction heats the cooking vessel itself almost instantly….. An electric current is passed through a coiled copper wire underneath the cooking surface, which creates a magnetic current throughout the cooking pan to produce heat. Because induction doesn’t use a traditional outside heat source, only the element in use will become warm due to the heat transferred from the pan. Induction cooking is more efficient than traditional electric and gas cooking because little heat energy is lost. Like other traditional cooktops, the evenly heated pots and pans then heat the contents inside through conduction and convection…. Important: For induction to work, your cookware must be made of a magnetic metal, such as cast iron or some stainless steels.

Jacinta: So I’m not sure if that gets closer to an explanation, but what’s surely missing is how magnetism, or a magnetic current, creates heat. It doesn’t use an ‘element’, but it must use something. I know that heat is energy, essentially, and presumably an electric current is energy, or force, like emf, which is also energy…

Canto: Yes it’s very confusing. The Wikipedia article gets into the maths fairly quickly, and when it describes applications it doesn’t mention cooking… Hang on, it takes me to a link on induction cooking. So here’s a definition, similar to the Frigidaire one, but a little more concise. Something to really zero in on:

In an induction stove (also “induction hob” or “induction cooktop”), a cooking vessel with a ferromagnetic base is placed on a heat-proof glass-ceramic surface above a coil of copper wire with an alternating electric current passing through it. The resulting oscillating magnetic field wirelessly induces an electrical current in the vessel. This large eddy current flowing through the resistance of a thin layer of metal in the base of the vessel results in resistive heating.

I’ve kept in the links, which I usually remove. For our further education. So it’s the resistance of the metal base of the pan that produces heat. Something like incandescent light, which is produced through the resistance of the tungsten filament, which makes it glow white (this was a light bulb moment for me). So you really have to use the right cookware.

Jacinta: Thanks for the links – yes, the key is that ‘resistive heating’, also called Joule heating. James Joule, as well as Heirnrich Lenz, independently, found that heat could be generated by an electric current, and, by experimental testing and measurement, that the heat produced was proportional to the square of the current (which is basically the emf, I think), multiplied by the electrical resistance of the wire. So you can see that the wire (or in cooking, the pot) will heat more readily if it has a high electrical resistance. This can be stated in a formula: , where P is the heating power generated by an electrical conductor (measured usually in watts), I is the current, and R is the resistance.

Canto: So we’ve made progress, but it’s the relation of magnetism to electricity – that’s what I don’t get, and that’s the key to it all. I think I understand that an electric current creates a magnetic field – though not really – and I get that an alternating current would induce an oscillating magnetic field, I think, but is this just observation without understanding? That electricity and magnetism are connected, so just shut up and calculate as you say?

Jacinta: So how, and why a high frequency alternating current creates a dynamic field, that’s what we’re trying to understand. And what’s an eddy current?

Canto: I think we’ve had enough for now, but we’re getting there….

Written by stewart henderson

August 27, 2022 at 5:20 pm

How Australia is faring on global indices

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park yourself here?

 

Many Australians were greatly relieved at the change of Federal government from May 21 2022. Australia hadn’t been faring well on the international stage, especially with respect to the global warming crisis, but also regarding political governance and other issues. Of course the Labor government has only been in office for three months, so I don’t expect judgements to have turned around significantly at this point. The purpose of this piece is to describe Australia’s position on a number of international surveys, and then to return to those surveys in about twelve months’ time to see if and how the view of Australia internationally has changed.

I was motivated to write this by a passage in David Brophy’s book China Panic, in which he mentioned two such international surveys, the CIVICUS monitor, which apparently measures democratic credentials, and Transparency International’s Corruption Perception Index. I’d never heard of these surveys, which is hardly surprising for a dilettantish autodidact. Three surveys I have monitored are the Economist Intelligence Unit’s Democracy Index, the OECD’s Better Life Index and the UN’s Human Development Index. So now we have five, and counting. What follows is my attempt to summarise their most current findings.

The CIVICUS monitor. CIVICUS is, as far as I can tell, not an acronym. Based in Johannesburg, the organisation describes itself as:

a global alliance of civil society organisations and activists dedicated to strengthening citizen action and civil society throughout the world…. Our definition of civil society is broad and covers non-governmental organisations, activists, civil society coalitions and networks, protest and social movements, voluntary bodies, campaigning organisations, charities, faith-based groups, trade unions and philanthropic foundations. Our membership is diverse, spanning a wide range of issues, sizes and organisation types.

According to Brophy, the CIVICUS monitor downgraded Australia’a democratic status (in the broad sense described above) from ‘open’ to ‘narrowed’ in 2019. The latest findings, from 2021, are unchanged. To explain, the monitor divides the world’s nations into 5 levels, which, top to bottom, are open, narrowed, obstructed, repressed and closed. On further inspection, I’ve found that there’s a ‘live rating’, last updated for Australia on 25/5/22, a few days after the election. Hopefully things will have improved by 2023. To compare a few other countries – New Zealand, Canada, Ireland, Uruguay, Suriname, Taiwan, Portugal and most Northern European countries are classed as ‘open’. Other ‘narrowed’ countries include Namibia, Italy, France, the UK, Japan  and Bulgaria. Obstructed countries include the USA, Brazil, South Africa, Ukraine, Poland, Indonesia and Morocco. A colour-coded map provides an at-a-glance reference to any country of interest. The repressed and closed countries can generally be guessed at. China, Vietnam and most Middle Eastern counties are classed as ‘closed’.

The Corruption Perceptions Index (CPI). The CPI is a product of Transparency International, which advertises itself thus:

Transparency International is a global movement working in over 100 countries to end the injustice of corruption. We focus on issues with the greatest impact on people’s lives and hold the powerful to account for the common good. Through our advocacy, campaigning and research, we work to expose the systems and networks that enable corruption to thrive, demanding greater transparency and integrity in all areas of public life.

First set up in 1993 by an ex-World Bank official, Peter Eigen and like-minded associates, first-hand witnesses of global corruption, the organisation was established in then recently re-unified Berlin.

An article in The Conversation, posted in late January 2022, points out that in 2012 Australia ranked level with Norway in 7th position as to ‘cleanness’. The 2021 index, to which The Conversation refers, sees Australia as having slipped to 18th while Norway has risen to 4th, out of 180 countries. Much of what Brophy writes in China Panic is an account of why the country I happen to have ended up in has fallen so far so fast. The Economist Intelligence Unit, which publishes the Democracy Index, is one of the sources for this index, along with Freedom House and the World Justice Project. The three equal top countries on this index are New Zealand, Denmark and Finland, and the bottom three are Somalia, Syria and South Sudan. Anyway, re Australia, this one will be worth watching over the next few years.

The Democracy Index. I’ve written about the Democracy Index, inter alia, in a previous piece. It’s produced by the Economist Intelligence Unit, associated with The Economist magazine in the UK. Here’s their raison d’être blurb:

The EIU Democracy Index provides a snapshot of the state of world democracy for 165 independent states and two territories. The Democracy Index is based on five categories: electoral process and pluralism, civil liberties, the functioning of government, political participation, and political culture. Based on their scores on 60 indicators within these categories, each country is then itself classified as one of four types of regime: full democracy, flawed democracy, hybrid regime or authoritarian regime

Australia ranks a fairly creditable 9th on the Democracy Index list for 2021, well below NewZealand (2nd) but also well above the country we’ve been showing so much allegiance to in recent decades, the USA, which ranks 26th and is considered a flawed democracy. According to the index’s ratings, the world is inching towards hell in a hand basket – 70% of the world’s nations have become less democratic in the last twelve months, and this downward trend has prevailed for some years. Australia, though, has been faring worse than most. I don’t have access to the previous rankings, but each nation is given an annual score out of ten. Australia’s 2021 score is 8.90, compared to 8.96 in 2020. The score has regularly dropped from a high of 9.22 in the years 2010-2012, the period of the Rudd-Gillard Labor Prime Ministerships.

The OECD Better Life Index. This measures the ‘life experience’ of an ‘elite’ group of about 40 of the world’s wealthiest countries, members of the Organisation for Economic Cooperation and Development, according to eleven different criteria, including education, environment, safety and health. When I first accessed the index, about 6 or 7 years ago, Australia was ranked number 2 across all criteria, behind the ever-triumphant Norway, and well ahead of the US in around 12th spot. Currently Australia is ranked 7th, and the USA 8th. Norway still ranks first.

On looking into Australia’s ranking for each criterion (the 11 criteria are housing, income, jobs, community, education, environment, civic engagement, health, life satisfaction, safety and work-life balance) I can’t help but scratch my head at some of the results. Australia ranks 1st for ‘civic engagement’, but 20th for ‘community’ (!!??). I would have thought that one entails the other. Also, Australia ranks 2nd for housing (but city rental has become unaffordable for most young people), and 2nd for education, which again surprises me from a general persecutive, though our post-grad sector definitely punches above its weight. At the other end of the spectrum, Australia ranks 30th for safety, another surprise. The OECD claims that the average homicide rate for member countries is 2.6 per 100,000 inhabitants. According to the Australian Institute of Criminology, Australia’s homicide rate for 2019-20 was 1.02 per 100,000, the highest in nearly ten years, but clearly well below the OECD average. Of course, homicide is only one measure, but I’ve not heard of Australia having a high crime rate in general. Strange. But the worst ranking is 33rd for work-life balance!? But having rarely worked a day in my life, I couldn’t possibly comment.

The UN Human Development Index (HDI). Here’s the blurb about this one:

The Human Development Index, or HDI, is a metric compiled by the United Nations and used to quantify a country’s “average achievement in three basic dimensions of human development: a long and healthy life, knowledge and a decent standard of living.” Human Development Index value is determined by combining a country’s scores in a vast and wide-ranging assortment of indicators including life expectancy, literacy rate, rural populations’ access to electricity, GDP per capita, exports and imports, homicide rate, multidimensional poverty index, income inequality, internet availability, and many more.

The HDI website only provides information from 2019 and places Australia in a tie with The Netherlands at 8th in the world, with a score of .944 on a scale from 0 to 1. Norway again gets top spot, just ahead of Ireland and Switzerland. Interestingly, Australia ranks higher than four countries it likes to compare itself with, the UK, New Zealand, Canada and the USA, but little explanation is given for the ranking, which appears to be have been stable for a few years.

So, to summarise, I don’t know what to make of all these indices, which I suspect subtly influence each other in their ratings. We appear to always make the top ten, but rarely the top 5. If we could take advantage of our climate and resources to be be a greater power in renewables, instead of lagging (except in domestic rooftop solar) as we have done over the last decade, we could really make the world pay more attention to us, for better or worse.

References

David Brophy, China Panic: Australia’s alternative to paranoia and pandering, 2021

https://monitor.civicus.org

Global Ranking

https://en.wikipedia.org/wiki/Democracy_Index

https://www.oecdbetterlifeindex.org/#/11111111111

https://worldpopulationreview.com/country-rankings/hdi-by-country

Written by stewart henderson

August 24, 2022 at 4:04 pm

an interminable conversation 5: the RET, Mike Cannon-Brookes, and Big Gas issues

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Jacinta: So I’ve heard of this thing called the Renewable Energy Target (RET) – in fact I first heard about it years ago but I’ve paid little attention. Tell me more.

Canto: There’s a government website, the Clean Energy Regulator site, which purports to explain everything. Here’s the briefest statement about it:

The Renewable Energy Target is an Australian Government scheme designed to reduce emissions of greenhouse gases in the electricity sector and encourage the additional generation of electricity from sustainable and renewable sources.

Of course they have much more to say, in positive-speak, about it all, but a wee footnote at the bottom caught my attention:

In June 2015, the Australian Parliament passed the  Renewable Energy (Electricity) Amendment Bill 2015. As part of the amendment bill, the Large-scale Renewable Energy Target was reduced from 41 000 GWh to 33 000 GWh in 2020 with interim and post-2020 targets adjusted accordingly.

I believe the ultra-conservative Tony Abbott was PM in 2015, and the Fossils were calling the shots, as Marian Wilkinson’s The Carbon Club relates. Anyway, it’s a certificate system based on megawatt hours of power generated, and the rather pathetic target was apparently reached, based on approvals of large solar and wind installations, in the second half of 2019.

Jacinta: That’s something perhaps, but the IPCC wasn’t particularly impressed. The Clean Energy Council’s website, Ecogeneration, has boosted the achievement, describing the RET as ‘the most successful emissions reduction policy of all time for Australia’s electricity system’. But it hasn’t had any competition! And ominously, Kane Thornton, CEO of the Clean Energy Council, is quoted as saying ‘the industry doesn’t need new subsidies, we just need certainty’, etc etc, which contradicts everything I’ve heard from Saul Griffith, Mike Cannon-Brookes and others… we’ve been subsidising the fossil fuel industry forever, haven’t we? It’s rebuilding our manufacturing base that needs subsidising. Renewable energy has already become the cheaper option, but we have no EV manufacturing here and only one PV manufacturer.

Canto: Interesting Mike Cannon-Brookes interview in the Financial Review, which introduces the term ESG to me. This stands for Environmental, Social and Governance, perhaps in that order, as factors to be considered in any investment. Which all sounds v positive. And he’s very positive about ESG, which is a positive thing.

Jacinta: Yeah, apparently he’s a billionaire. How the fuck do people become billionaires? Why is it ever allowed?

Canto: Yeah, obviously it’s not just about working hard, like the Congolese in the diamond mines, and various slave populations over the centuries, whose only reward was death. Nature just ain’t fair. Herr Cannon-Brookes is co-founder of a company called Atlassian, which I’ve never heard of. Nor have I heard of their major products, such as Jiro and Trello, which are used by ‘teams’, but I don’t think they play soccer.

Jacinta: Sounds like they’re in the business of business, which is certainly none of our business.

Canto: Yeah, it’s probably all about digital environments. We’re about 40 years out of date. We need to stop reading books, paper is so 20th century.

Jacinta: Anyway, getting back to renewable energy …

Canto: Well this interview with Cannon-Brookes, he sounds pretty sincere, for a billionaire. They’re just people I suppose. If a bit weird. He’s very positive about renewables, and running his business that way, and pretty honest about the issues – like offloading the problem onto others, as he admits to having done, and facing that issue squarely. You know, like Australia exports coal and gas, and doesn’t take responsibility for the emissions. Like Norway.

Jacinta: They don’t have to take responsibility, the way the current system works. Apparently, as of July 2020, Australia became the world’s biggest gas (LNG) exporter, overtaking Qatar. That’s from the Climate Council. It’s hard to keep track of all these organisations. Anyway, Australia was exporting about 80 million tonnes of LNG per year two years ago. According to the latest, it was 77.7 MT (in 20-21 financial year). The article said it has ‘retained its crown’ as the world’s largest exporter. Shouldn’t that be a dunce’s cap?

Canto: So many people are late in getting with the program. By the way, China has taken over from Japan as our number one LNG buyer – adding to our problems with that fascist government. In any case the argument would be – and I’ve heard it stated in a public forum – that we owe our wealth as a nation to these exports, and by extension, to our trading relation with China. .

Jacinta: Well, it’s interesting that the price of gas is rising domestically. Presumably this has something to do with so much of our gas going offshore? And renewables, though growing, are hardly ready to fill the domestic energy gap, right?

Canto: So this is all new stuff to get my head around, but a ‘Bloomberg Green’ video linked below has it that the Australian Competition and Consumer Commission (ACCC) has produced an interim gas report, a forecast for 2023. It predicts that the supply of gas for next year will fall short of demand by about 56 petajoules – 3% of total demand. This doesn’t sound like much, but with rising gas prices… Anyway the ACCC is recommending that the federal government bring into force the ‘Australian Domestic Gas Security Mechanism’, pressuring LNG exporters to reserve some of those earmarked exports (70 to 75 percent of production) for the domestic market. Now, some 11% of those exports aren’t covered by long-term contracts – they’re available for those as bids for them, and there might be a few countries bidding, considering the global situation.

Jacinta: Hmmm, sounds like a seller’s market, with impoverished buyers, including domestic ones. So the idea is that the government can intervene to force gas exporters to sell some of their stuff here, with reduced profits?

Canto: Yes, but whether they do is a question. The video goes on to talk about Australia’s new emissions reduction target of 43% on 2005 levels by 2030, with the aim of net zero emissions by 2050. Interestingly, the Bloomberg economist says that while it’s good news to get clear targets after years of nothing much, the targets are still a bit weak. Most notably, only 3% of passenger vehicles sold last year were EVs, and with no manufacturing here in the foreseeable future, the chances of EVs reaching 89% of sales by 2030 – Labor’s target – are surely minuscule.

Jacinta: Yes, but all the other cars purchases would be overseas-made vehicles, wouldn’t they?

Canto: Hmmm, so there might have to be legislation to favour EV imports, as well as plenty of infrastructure… And a turnaround in public attitudes, which I don’t presently see.

Jacinta: Returning to gas, the Australia Institute, which appears to be a left-leaning public policy think tank, has a critique of our gas exporters in another, very brief, video. It just advises turning our backs on gas tout de suite. Forget reserving gas for the domestic market – which might involve something more or less in the form of a bribe to the exporters. Instead, electrify everything, of course. More pronto than pronto, to make up for a lost decade of relative inaction. They describe it as a gas export crisis, in which domestic prices are soaring because so much of our gas is going offshore. A win-win for the gas companies.

Canto: So, is this the situation? Gas companies are in the business of profit. They sell gas overseas, even at the expense of the domestic market, because they can, because they’re owned by private individuals, they can sell to the highest bidder. And If this means gas is scarce domestically, and in high demand, because we’ve become dependent on gas, we haven’t been weaned off it, the gas companies can make another killing on the domestic market? They’re holding us to ransom, so to speak?

Jacinta: Oil and gas companies in the US as well as in Australia are making huge profits currently, due to scarcities caused by war, embargoes and such…

Canto: The Australian Domestic Gas Security Mechanism was designed to ensure sufficient domestic supply, but it’s not very efficient, and the domestic supply target is too low. Some state governments, notably Western Australia, have a higher domestic reserve, but of course what we need is to switch to renewable-based electric as quickly as possible, to get out from under the control of the fossil fuel barons.

Jacinta: Are gas companies subsidised here?

Canto: Do koalas shit in the trees? Renew Economy has a scathing article about this, posted today. It describes companies like Santos recording super-massive-record profits this year, and the term ‘war profiteering’ is mentioned. This has also been at the expense of the domestic market. Here’s a quote:

Santos categorically stated its project would not affect the domestic market because it would not buy gas out of the domestic market. But that is exactly what it has done. Santos bought large volumes of gas out of the domestic market in the first half of 2022, forcing domestic prices above export prices in the last six months. These actions have generated super profits, gouged from domestic gas consumer and forcing up domestic electricity prices to unaffordable levels. Santos has broken its approval conditions and IEEFA calls on the government to cancel their export licence.

The IEEFA, for our info, is the Institute for Energy Economics and Financial Analysis. Bruce Robertson, who wrote the Renew Economy article, has a similar piece on the IEEFA website. The thing is, the domestic reserve could be raised, and made non-negotiable (it isn’t at present) without having much of an effect on these windfall profits. As it is, gas companies are largely ignoring existing reserve requirements. The ACCC has the capacity to prosecute but apparently has no intention of doing so. They’re also doing nothing to tackle these companies’ collusion re price-fixing and tax avoidance. There’s something rotten about all this. Clearly we’re not going to wean ourselves from gas as quickly as we should, but we certainly shouldn’t be pumping up and sending off ever more of the stuff.

Jacinta: Well, yes, considering that the aim is to electrify everything, and people are starting to get on board with this, that means no new gas fields, so what are these companies going to do with these massive extra profits, other than line the pockets of CEOs and their immediate underlings?

Canto: Well, there will still be offshore markets for the foreseeable, so keep on despairing. Two months ago, the Sydney Morning Herald ran an opinion piece by Tony Wood of the Grattan Institute, arguing for a ‘windfall profit tax’ considering that some importers are paying ‘more than four and up to 10 times the contract prices’. The Federal Treasurer, Jim Chalmers, isn’t interested. And so the rich get richer, for the time being….

References

https://www.cleanenergyregulator.gov.au/RET/About-the-Renewable-Energy-Target

Marian Wilkinson, The Carbon Club, 2020

RET reached ahead of 2020 target

https://www.afr.com/policy/energy-and-climate/mike-cannon-brookes-on-esg-agl-and-why-australia-needs-no-more-gas-20220616-p5au3b

What the frack? Australia overtakes Qatar as world’s largest gas exporter

https://www.upstreamonline.com/lng/australia-remains-worlds-top-lng-exporter-but-it-could-lose-its-crown-this-year/2-1-1147625

Santos windfall: Australia is swimming in subsidised gas and we’re giving it away

https://ieefa.org/resources/why-government-must-break-eastern-australias-gas-cartel

https://www.smh.com.au/national/all-australians-should-share-in-record-profits-from-overseas-gas-sales-20220608-p5aryk.html

 

 

Written by stewart henderson

August 17, 2022 at 11:16 pm

Amazing internet, female science communicators and fighting global warming: an interminable conversation 4

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from Renew Economy – SA doing quite well

 

Jacinta: As I’ve said many times – or at least I’ve thought many times – the internet is surely the greatest development in human history for those interested in self-education. Can you think of anything to compare?

Canto: Not really. The printing press was important, but literacy rates were much lower when that came out – which makes me think that universal education, which includes literacy of course, must be up there. But of course it was never really universal, and I suppose neither is the internet, but it appears to have penetrated further and wider, and much faster than any previous technology…

Jacinta: Universal education was more or less compulsory, and so very top-down. Not self-education at all. The internet gives every individual more control…

Canto: And most choose to stay within their own social media bubble. But for those keen to learn, yes the internet just gets more and more fantastic. 

Jacinta: And the trend now is for spoken presentations, with bells and whistles, rather than reams of writing, which can be off-putting…

Canto: Well, our stuff is pretend-speak. We don’t do videos because we’re both extremely ugly, and even our voices are hideous, and we haven’t a clue about bells and whistles. 

Jacinta: Sigh. Consigned to obscurity, but we must perforce mumble on into the vacuum of our little internet space. Even so, I’d like to enthuse, however impotently, about the many excellent female science presenters out there, with their vodcasts or vlogs or whatever, such as Australia’s Engineering with Rosie, as well as Kathy loves physics and history, Sabine Hossenfelder and Dr Becky. And I’ll keep an eye out for more.

Canto: But of course we still love books. The most recent read has been Saul Griffith’s The Big Switch, a call to action on renewables, particularly here in Australia. 

Jacinta: So with a change of government, Australia is now going to try and catch up with the leading nations re renewable energy and generally changing the energy landscape. So it’s time to turn to the Renew Economy website, the best Australian site for what’s happening with renewables. First stop is the bar graph that’s long featured on the site. It shows that the eastern states, Queensland, NSW and Victoria, are the problem states, still heavily reliant on coal. Victoria is arguably worst as it relies on brown coal for about two thirds of its supply. 

Canto: And the other two states use black coal, but they’ve developed a lot more solar than Victoria. They are, of course, a lot sunnier than Victoria. What’s the difference between the two coals, in environmental terms? 

Jacinta: Black coal, aka anthracite, is generally regarded as a superior fuel. It contains less water than brown coal, aka lignite, and more carbon. You have to use quite a lot more brown coal – maybe 3 times as much – to extract the same amount of energy as anthracite. According to Environment Victoria,

Brown coal is pulverised and then burned in large-scale boilers. The heat is used to boil water and the steam is used to drive turbines that generate electricity. When brown coal is burnt it releases a long list of poisonous heavy metals and toxic chemicals like sulphur dioxide, mercury, particulate matter and nitrogen oxides. By world standards these pollutants are poorly monitored & controlled, and they impose a staggering health cost of up to $800 million every year.

I’ve left in the links, which are to other Environment Victoria articles. Clearly this website isn’t government controlled, as it castigates heavily subsidised ‘boondoggle’ projects intended to keep the brown coal afloat (very problematic for mining). These projects have apparently gone nowhere. However the site does mention the ‘recent’ announcement of an electric vehicle manufacturing plant in the Latrobe Valley, providing at least 500 jobs. But since the article isn’t dated, I don’t know how recent it is. PLEASE DATE YOUR ARTICLES. 

Canto: Yeah, and please do your research Jazz. That plant, announced in 2018, was scrapped last November. Apparently it was announced ahead of the 2018 election. And over-hyped, as it was never guaranteed that the ‘promised’ 500 jobs would be created. Politics. 

Jacinta: Sad. Manufacturing has been in a sorry state in Australia for years. As Saul Griffith points out, we rely largely on the raw materials – crushed rocks – we export to keep our economy going, but if we could switch to other crushed rocks for the growing renewable energy economy we would be even better off. Further, if we added value through processing this material at home, we might be even better off financially, and we wouldn’t have to import those processed materials as we do now. Our two biggest imports are petrol and cars. If we could produce that stuff here we wouldn’t be paying for another country’s production costs, according to Griffith. Though I’m not quite sure if it’s that simple. 

Canto: So you’re talking essentially about manufacturing in Australia. The Reserve Bank (RBA) has an interesting article on this topic, and here’s a quote from the opening summary: 

Manufacturing output and employment have fallen steadily as a share of the Australian economy for the past three decades… the increase in the supply of manufactured goods from low-cost sources abroad, exacerbated by the appreciation of the Australian dollar during the period of rising commodity prices, impaired the viability of many domestic manufacturers and precipitated the closure of some manufacturing production over the past decade. While the recent exchange rate depreciation has helped to improve competitiveness of Australian producers, so far there is only limited evidence of a recovery in manufacturing output and investment.

Economics isn’t my strong suit, but I think I understand what ‘exchange rate depreciation’ means. Something like the exchange rate has swung a bit more in our favour (for home-grown manufacturing) than it was before..

Jacinta: But wouldn’t the exchange rate between us and other countries vary greatly from country to country? Or maybe they take an average, that’s to say of the countries we tend to trade with?

Canto: I suppose so. The article goes on to say that manufacturing hasn’t declined so much as commodity exports have increased. Commodities being raw materials, mostly. And by the way, this article is from the June quarter of 2016, and I suspect things have gotten worse for this gap between manufacturing and commodities. So, not so out-of date re trends. It claims that ‘over the 2000s, strong Asian demand for Australian commodities led to a sharp increase in the terms of trade and an appreciation of the Australian dollar’. 

Jacinta: Well, we all appreciate the Aussie dollar…

Canto: Appreciation just means a rise in value. An increase in the terms of trade means an increase in the trading price agreed by any two countries, for example Australia and China, our big bogey man trading partner. Here it might mean beneficial terms of trade for Australia specifically. So basically, manufacturing has stagnated, and declined as a percentage of total output, which includes commodities. Manufacturing industries as an employer have declined quite sharply – as I can personally attest to. I’ve worked in five different factories in my life, all of which have since closed down – for which I take no responsibility. 

Jacinta: So there would be a lack of skilled workers in manufacturing, unless… do we make solar panels here? And what about the old car factories we had here – Mitsubishis and Holdens, remember? Though I presume making EVs would require a whole different skill-set, and besides, wouldn’t it be largely automated? 

Canto: Well, in February – that’s 2022 – the Australia Institute posted a highly optimistic media release entitled ‘Australia ready to become sustainable EV-making powerhouse: new research’. And with the new federal government elected in May, this hope, expressed in a report from the AI’s Carmichael Centre, Rebuilding Vehicle Manufacturing in Australia: Industrial Opportunities in an Electrified Future, may actually be realised, at least partially. But before I explore that report – solar photovoltaic manufacturing in Australia. A recent (early July) Guardian article reports that ‘China controls over 80% of the global photovoltaic (PV) solar supply chain, with one out of every seven panels produced worldwide being manufactured by a single factory’. And China is actually increasing production, so as to dominate the market. Diversification is urgently required. Meanwhile, Australia is suffering a labour shortage in the field. The International Energy Agency (IEA) has found that ‘one in three installation jobs in Australia – including electricians and installers – were unfilled and at risk of remaining unfilled in 2023’. Tindo Solar is our only home-grown PV manufacturer, and is expanding its output, but clearly this is dwarfed by China’s production. Also there’s a problem with expending production here because, currently, it actually creates more carbon emissions. We need to ‘create renewables with renewables’, which local experts are saying is now more cost-effective than ever. So, back to the report on vehicle manufacturing in Australia. It’s a job trying to access the full report, so I’ll rely on the media release. It describes our country as ‘uniquely blessed’ to rebuild our car manufacturing capabilities, retooled to EVs, but this will require essential government input – a view very much consistent with Griffith’s. Here are some of the recommendations from the report:

  • Establishing an EV Manufacturing Industry Commission
  • Using tax incentives to encourage firms involved in the extraction of key minerals – primarily lithium and rare earths – with local manufacturing capabilities, especially emerging Australian EV battery industries
  • Introducing a long-term strategy for vocational training, ensuring the establishment of skills to service major EV manufacturers looking to set up operations Australia
  • Offering major global manufacturers incentives (tax incentives, access to infrastructure, potential public capital participation, etc) to set up – especially in Australian regions undergoing transition from carbon-intensive industries
  • Introducing local procurement laws for the rapid electrification of government vehicle fleets

Jacinta: So, as Griffith points out, we need to do some lobbying for this ourselves. Here in SA, we have a sympathetic state government as well as a federal government keen to make up for lost time, or at least saying all the right things. Where do we start? 

Canto: The Clean Energy Council has a website that encourages everyone to get educated (they cite a number of resources such as Renew Economy and ARENA), to spread the word, and of course to actually invest in renewable energy, which we, as impoverished public housing renters, aren’t in a great position to do, though we are trying to get our Housing Association to explore renewable options, and to lobby the government in our name. 

Jacinta: I think I’m starting to feel more optimistic…

References

Saul Griffith, The big switch: Australia’s electric future. 2022

Difference Between Black and Brown coal

Nem Watch

https://www.abc.net.au/news/2021-11-10/electric-vehicle-factory-deal-in-latrobe-valley-collapses/100608074

Australia ready to become sustainable EV-making powerhouse: new research

Click to access bu-0616-4.pdf

https://www.carmichaelcentre.org.au/rebuilding_vehicle_manufacture_in_australia

https://www.theguardian.com/australia-news/2022/jul/08/australia-could-see-a-solar-cell-renaissance-if-global-supply-chain-is-diversified

https://www.cleanenergycouncil.org.au/herenow/get-involved

Written by stewart henderson

August 6, 2022 at 7:29 pm

more oxytocin fantasies: an interminable conversation 3

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not sure if this measures a significant difference

 

Canto: So, as it turns out, the bonobo-oxytocin connection is all the rage on the internet. I mean, there are at least two articles on it. Here’s a quote from a PubMed article called ‘Divergent effects of oxytocin on eye contact in bonobos and chimpanzees’:

Previous studies have shown that bonobos and chimpanzees, humans’ two closest relatives, demonstrate considerable behavioral differences, including that bonobos look more at others’ eyes than chimpanzees. Oxytocin is known to increase attention to another’s eyes in many mammalian species (e.g. dogs, monkeys, and humans), yet this effect has not been tested in any nonhuman great ape species.

Jacinta: Hmm, so how do they know this? Presumably they’ve dosed subjects with oxytocin and measured their eye contact against controls?

Canto: No no, they know that bonobos have more eye contact than chimps, simply from observation. So they might infer from this that bonobos produce more oxytocin naturally than chimps…

Jacinta: So do women produce more oxytocin than men I wonder? I presume women make more eye contact than men.

Canto: Well in this study they dosed both bonobos and chimps with oxytocin, and the effect – more eye contact – was greater in bonobos than chimps. In fact, chimps even tended to avoid eye contact when shown images of conspecifics.

Jacinta: So, it’s a matter of interplay between this hormone/neurotransmitter and social conditioning?

Canto: Maybe, but you’d think that an increase in this supposedly touchy-feely hormone would act against social conditioning. Isn’t this the point of that drug, ecstacy? That it reduces social inhibitions…  But presumably nothing is ever so simple. Being poor, I only have access to the abstract of this paper, but another abstract, which looks at the effects of oxytocin and vasopressin on chimps, describes them as neuropeptides, just to confuse matters. The abstract also refers to about a dozen brain regions, as well as specific oxytocin and vasopressin receptors, so it gets pretty complicated.

Jacinta: Okay, vasopressin… from Wikipedia:

Human vasopressin, also called antidiuretic hormone (ADH), arginine vasopressin (AVP), or argipressin, is a hormone synthesised from the AVP gene as a peptide prohormone in neurons in the hypothalamus, and is converted to AVP. It then travels down the axon terminating in the posterior pituitary, and is released from vesicles into the circulation in response to extracellular hypertonicity (hyperosmolality). AVP has two major functions… etc etc

Canto: Okay thanks for that, let’s stick with oxytocin for now. It’s produced in the hypothalamus, a smallish region buried deep within the brain, just below the larger thalamus and above the even smaller amygdala. It releases and manages a variety of hormones. Brain signals are sent to the hypothalamus, exciting it to release oxytocin and other hormones, which are secreted into the bloodstream by the posterior pituitary gland….

Jacinta: Can you tell me what oxytocin is actually made of? Its structure? The term ‘hormone’ is just a black box to me.

Canto: Okay, here’s a diagram of oxytocin to try and make sense of:

It’s a polypeptide. A peptide is basically an amino acid chain. FYI:

An amino acid is an organic molecule that is made up of a basic amino group (−NH2), an acidic carboxyl group (−COOH), and an organic R group (or side chain) that is unique to each amino acid. The term amino acid is short for α-amino [alpha-amino] carboxylic acid.

Jacinta: So these are coded for, ultimately, by genes?

Canto: Yes, we’re heading backwards here, but each amino acid is encoded by a sequence of three of the four base pairs in our DNA. Anyway oxytocin, among other things is sometimes given to women while in labour. It helps with the contractions apparently. I’ve also heard that the recreational drug ‘ecstasy’, or MDMA, works essentially by releasing oxytocin.

Jacinta: It just so happens I’ve found an interesting 2014 paper published in Neuropsychopharmacology, my new favourite journal, called ‘Effects of MDMA and Intranasal Oxytocin on Social and Emotional Processing’, and here’s a quote from the abstract:

Oxytocin produced small but significant increases in feelings of sociability and enhanced recognition of sad facial expressions. Additionally, responses to oxytocin were related to responses to MDMA with subjects on two subjective measures of sociability. Thus, MDMA increased euphoria and feelings of sociability, perhaps by reducing sensitivity to subtle signs of negative emotions in others. The present findings provide only limited support for the idea that oxytocin produces the prosocial effects of MDMA.

Canto: That is interesting. If that finding can be replicated, I’d say forget the MDMA, dose people with oxytocin. A small but significant increase in feelings of sociability might just be enough to transform our human world.

Jacinta: Hmmm. Small but significant – that sounds a mite contradictory.

Canto: Not the same as significantly small. That slightly significant dose, administered to Messrs Pudding and Pingpong and their enablers, might’ve saved the lives of many Ukrainians, Uyghurs and advocates of multiculturalism, democracy, feminism and other wild and woolly notions. And it doesn’t really transform characters, it just softens their edges.

Jacinta: Yes it’s a nice fantasy – more productive than butchering the butchers, a fantasy I occasionally indulge in. But not workable really.

Canto: Why not? We dosed petrol with lead, and look at how that worked out. It certainly had an effect. In Japan they still use radium baths (at very low levels) for health purposes, even claiming it as a cure for cancer. I’m not sure if oxytocin baths can ever be a thing, but if so I’m sure there will be early adopters.

Jacinta: Well, it’s good to think positively. Oxytocin is often thought of as a bonding hormone between mother and child. The key would be to ensure it facilitates a more general bonding: to cause Mr Pingpong, for example, to see Uyghur, Tibetan, Yi, Limi, and all the other non-Han ethnicities in China as his sisters – or lovers even, revolting as that would be to those peoples.

Canto: Better than being their oppressors and exterminators.

Jacinta: Slightly. But I wonder, quite seriously, if, assuming such a dose of bonding could be effectuated, we could still function as the sometimes rational, problem-solving, highly creative species we indubitably are. Would there be a price to pay for all that oxytocin? And how would this affect all those other hormones and neurotransmitters and all their myriad effects? Humans are notorious for causing extra problems with their solutions, e.g lead, DDT, etc etc.

Canto: Well, there’s no need to worry about the fallout from this solution as yet. I just googled Putin and oxytocin together and came up empty. Obviously we’re way ahead of the curve.

Jacinta: Haha, it’s not a curve these days, it’s a pivot. Get with the program!

References

https://pubmed.ncbi.nlm.nih.gov/33388536/

https://www.yourhormones.info/hormones/oxytocin/

https://www.acs.org/content/acs/en/molecule-of-the-week/archive/o/oxytocin.html

https://www.britannica.com/science/amino-acid

https://www.wsj.com/articles/BL-JRTB-11551

 

Written by stewart henderson

August 4, 2022 at 10:38 pm