Friday, October 04, 2019

SF6: how unknown greenhouse gas may almost match, maybe trump the known one

Many people have completely lost their mind. The time for discussions and rational thinking has ended, they say, and now it's the right time to mindlessly listen to mentally disordered teenagers and to panic. Well, the fact that it is implausible for the climate change to cause global problems, at least in the following centuries, doesn't matter for them.

In reality, we known many examples of extra CO2 emissions that are caused "somewhere in the process", at a slightly less visible place – the production of batteries or electric cars, wind turbines, the tractors moving over the fields while producing biofuels, and many more.

Matt Ridley has pointed out this great new example related to the wind energy – SF6; click for a BBC story. Sulfur hexafluoride. I can't resist to brag that we call it "fluorid sírový" in our superior Czech chemical terminology. The suffix in the adjective "-ový/-ová" (the same one we add to create female surnames) actually contains the "hexa" information (we have different suffixes for the other oxidation states 1-8 which are called the "oxidation number" in Czech), "síra" is sulfur. Wouldn't it be cleverer if oxides of carbon weren't monoxides, dioxides etc. but rather carbonic, carbonish, carboneque, carbonian, carboner, carbonest, carbonisian, and carbonician oxides, or whatever suffixes the English linguists would invent instead?

It's a gas that is routinely added to prevent short circuits. In recent years, it just happened that the wind power plants needed a very large amount of this gas. You know, the people around the new wind power plants are faithful Gr#tins who are said to make the world a better place by doing mindless crazy things. So by preventing short circuits in the wind turbines and the stations connected to them, they're surely preventing global warming as well, right?

Here you can see how it's absolutely critical for these "invisible effects" to be managed by experts who actually have the expertise and who are careful enough to know what they are doing. SF6 simply is a greenhouse gas, too. Its global warming potential is said to be between 22,000 and 24,000 – which means that one ton of SF6 produces as much warming as 22,000-24,000 tons of CO2; SF6 is often labeled the world's most potent greenhouse gas. This comparison is made over the 100-year time scale.

The global warming potential of SF6 is 16,000 and 33,000 over the 20-year and 500-year periods, respectively. All these numbers are much larger than one. Most of this largeness may be attributed to the huge lifetime of SF6 in the atmosphere – it is a whopping 3200 years. If you look at the distant enough future, thousands of years from now, most of the extra CO2 will be reabsorbed while SF6 will be stuck in the atmosphere.

What is the warming caused by the greenhouse effect from this SF6 we are adding?

We must know the overall emissions first. Mankind produces some 36 billion tons of CO2 (the carbon atoms make about 10 billion tons, the remaining 26 billion tons is the oxygen atoms). SF6 emissions are growing rapidly but, as you can also see on this PDF page, they are partly a corporate secret. So we can't even learn how much SF6 is emitted. The page quotes an estimate 10,000 tons. But it's totally plausible that the actual number is higher, perhaps much higher.

Multiply it by the global warming potential 23,000 – and you will get some 230 million tons of the CO2 equivalent from SF6 emissions annually. That's about 150 times fewer than the actual CO2 emissions. But you know, wind energy is also producing less than 5% of the world energy. Multiply the SF6 emissions to 20, to upgrade wind energy to 100% of the current energy production, and then the CO2-to-SF6 ratio of the greenhouse effect would be just 7 to 1 or so.

And it's simply damn possible that the actual SF6 emissions are 7 times higher than the estimates. It's also possible that aside from SF6, there are some other gases emitted somewhere in the process whose greenhouse effect may be comparable to the SF6 emitted during the same time. Or gases that cause warming by reducing the cloud cover because they dissolve the cloud condensation nuclei. Or something else.

You know, when I was writing the paragraphs above, I didn't know the answer in advance. No one can know the answer in advance. I wasn't even quite sure (although I expected) that the SF6 warming would be smaller than the actual warming from CO2. And I am not 100% sure that I will insist on my numbers or admit a mistake after a reader finds it. The outcome depends on rather nontrivial calculations – although my calculation was straightforward. You can't replace these calculations by a religious faith. This is really the main point of my article.

One always has to think, the society should think, and abstract enough quantities such as the greenhouse gases and their potency which we can't see with our naked eyes (only Greta PBUHer may see CO2 in the air) simply must be checked by someone who is calm, honest, competent, and who knows not only the required elementary school algebra but also the relevant physics and chemistry and some engineering to be sure that the proportionality-based calculations aren't naively overlooking some extra effects or nonlinearities etc. Sometimes the elementary school algebra isn't enough and you need to do simulations of differential equations and more.

Similar comments apply to the solar panels, batteries that are supposed to store the energy from the "preferred" intermittent sources, and other parts of the "better world" that is being pushed down our throats by the Gr#tins. Even if the greenhouse effect caused by humans were important in any sense – it is not – this answer would still open lots of detailed technological questions about the procedures that are actually involved in one technology or another. The right method to optimize an abstract quantity is always a scientific or technological question that must be primarily analyzed by experts – it is never primarily a moral, political, let alone religious question.

And if some dangers became real and urgent – there are no dangers related to the climate today, let alone dangerous ones – it would be even more important to do the calculations and the choice of technologies properly. It would be even more important to rely on educated, skillful, intelligent, and calm experts.

Of course, the radicalized people may react to observations about SF6 or any "complex subtleties" in three basic ways: either they admit that their whole mindless approach was wrong and they fix it; or they will keep on denying the effect of SF6 because that's what most of them have done so far and this denial is arguably a part of their religious orthodoxy, as they see it and worship it; or they may admit that SF6 may also matter and they will better ban the wind turbines, too. The second reaction is a path to ban any progress because the opinions about anything can never change again; the third reaction is a path back to the caves because any kind of life of billions of people outside the caves unavoidably involves similar complexities.

No comments:

Post a Comment