Exergy seems to be in the currents running through my podcast subscriptions.

@PlanetCritical has an interview with Tânia Sousa about ‘Exergy Economics’ where the emphasis is on specific examples in service to explaining the concepts (56 minutes)
https://overcast.fm/+BTFx1qLQ0U

And Nate Hagens has a very clear monologue that places exergy in the wide thermodynamic boundary of our behaviour (30 minutes) https://overcast.fm/+BTumUml6tU

I found both illuminating

Exergy Economics | Tânia Sousa — Planet: Critical

You’ve heard of energy—but do you have any idea what exergy is? On today’s astounding episode of Planet: Critical, scholar Tânia Sousa explains the concept of exergy—the quality of energy—and why it is critical to understanding our energy systems, our economies, and energy transitions. She explains energy degradation, energy efficiency, and the how differences in available energy actually create the necessary gradients for life to happen. What this means, however, is that the pockets of high quality energy deposits around the world are a gift—and when we go through them, by burning all the oil or mining all the mines, then we will find ourselves in a world where we are capable of doing much less useful work. Planet: Critical is approaching its five year anniversary, and yet this conversation felt like the very beginning of this journey, when every episode was a revelation. And so it feels important to end the year with this mind-blowing hour. Happy festivities to one and all. See you in 2026. 🌎 Subscribe to…

…The key concept is that every time work is done (moving a limb, having a thought, heating a home, generating a stupid LLM response) the scope of the operating differential between the power source and the environment (in which the work is to be done) governs the amount of work that *can* be done.

This is a power source’s exergy.
https://en.wikipedia.org/wiki/Exergy

And thus not all energy sources are created equal. Some offer innately higher gradients.

Exergy - Wikipedia

…What Nate does really well, in my view, is put this in context of the 4th law of thermodynamics.

“The maximum power principle says that if energy is available, systems will self-organize to access and use it. And flatten that gradient over time. When there’s a usable gradient and positive feedbacks, whatever designs, behaviors and structures pull more useful power tend to outcompete their alternatives…

…“That's the fourth law in a nutshell. Successful competing systems evolve to maximize power, the sweet spot of as much energy as quickly as possible.”

Look around in the news and you can see the world’s greediest doing that to a greater degree than the next person, everywhere. But…

“There's a problem. In a finite world, accessing maximum power can, at certain times, like now, imply less power available later…

…“Fossil energy gives us an explosive burst of growth, but not only are fossil fuels finite, they’re also destabilizing the climate that sustains their continued use.

Sometimes, like now, the very success of energy capture becomes the seed of an organism’s or a species’ undoing.

So here’s the question I want to begin to explore. If life self organizes to maximize energy flow, and we homo sapien sapiens figured this out, is there any chance we can recognize and bend this rule?

…“Can conscious, self-aware creatures like us introduce something akin to a fifth law of thermodynamics?

Imagine a system that maximizes not instant power, but power through time that learns to optimize something like endurance. In other words, a principle of maximum *sustained power*.”

Sounds to me like the question the rest of our lives needs to figure out some lasting answers to

…One of the themes in the discussion with Tânia above is mining. It’s only really skated over, but just enough to highlight that mining is a gradient too.

And one of the qualities of transforming energy is degradation. The process of doing transformation a lot, without invoking the processes of life, is the lowering of gradients *rapidly*.

In Mark’s linked post the question is “What if we don’t have enough?” But the question is also “What happens when we think we do?”

https://mstdn.social/@markhburton/115756784737058486

…Above I said “without invoking the processes of life” because…

I’m no physicist or ecologist or student of entropy but my superficial understanding is that life seems to have engineered some extremely valuable tricks in that it manages to slow entropy. Like industrialism, it captures energy from the environment but, crucially, life does it with unparalleled efficiency and in a way where the byproducts (organisms and their natural waste streams) are recycled regeneratively…

…Crucially for modernity, industrialism is extremely far removed from the tricks that life can do. Its major dynamic is degradation: the flattening of gradients that are never to be regenerated on human timescales.

We cannot just step away from this because we are all inducted into this pattern.

But that pattern cannot last…

…Whether we have ‘enough’ for one initial round of an ‘energy transition’ (that isn’t a transition at all because it is intent on powering more transformations in aggregate) is very far from the only pertinent question to grapple with.

It would be good if we could start to engage with this more broadly than niche degrowthers

…appending to the above exergy-themed thread, its tl;dr is essentially this post from Graydon

https://canada.masto.host/@graydon/115758794075467055

Graydon (@[email protected])

Efficiency is not a suitable objective. Efficiency is one measure by which one can usefully compare equivalently effective processes to achieve an objective. tl;dr, it doesn't matter how effectively you produce something that doesn't work. And you do have to (eventually) define "works" if you want to know what you're doing. (Arguments for efficiency rot my socks, and I've been seeing a bunch go by today.)

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@urlyman This thread continues to get to the point...
#systembreakdown
@SusiArnott I am a broken record (with some variation)