Future of energy and thermodynamic cycles

Yesterday the conEnergia conference on future prospects of energy consumption has taken place in the beautiful renaissance theater Bibiena of Mantova. Here a few notes on the seminars (I expand on my own intervention).

Matteo PolettiniIntroduction: energies in transformation

“In transformation” =  entropy.

Thermodynamics is the science of energy management. It grew alongside the industrial revolution, at a time when resources were virtually infinite. The infinity of resources is inbuilt in the foundations of Statistical Mechanics, the modern formulation of thermodynamics I work on, where it is assumed that some “infinite sink” of resources is present: in other words, that things thrown into the environment do not come back. In a way, thermodynamics is the cultural product of its time. As resources on planet Earth become scarce, so thermodynamics needs to evolve as well.

The title the conference organizers proposed is “from the line to the circle”. Let me delve on this.

The first law of thermodynamics states that energy is conserved. The second law states that energy’s quality is degraded (forget about the formulation ” the entropy of the Universe does not decrease”, that doesn’t make sense as it has no operational value). Rather, there is a whole collection of second laws, each peculiar to a machine or process. They usually go like: “it is impossible for a cyclic process to … as its only effect”. What fills the dots depends on the machine under consideration. For example: “to transfer heat from a cold to a hot reservoir” etc. Let us dissect this sentence. First, the second law signals an impossibility: from a practical point of view, it is to be used not to build things, but to be skeptical about things. It is the law of skepticism, almost an ethical judgement on the methodology by which we conduct our research. Second: it has to do with a cyclic process within the system; this is necessary if we want to restart the process and initiate its industrial reproduction. Third: the “to be filled” sentence always represents a “linear” non-cyclic transfer of some resources across the environment, from one reservoir to another. Finally: as its only effect. So, if we include further effects we might be able to operate the cycle in the other direction, and revert the flow through the environment, thus closing the environmental cycle. Then, it might be feasible to, say, recycle what has already been trashed. But now the newer effect (or, more typically, effects) will have opened up other noncyclic processes in the environment, and so on head so on. If we really want a so-called “circular”, or “cradle-to-cradle” economy, we need to close cycles sure*, but in doing so we need to assure that we don’t open other ones, and we resort to the one and only process that has the right to remain linear, that of the sun’s life **.

Often in energy-related news one hears “zero-emission” stuff has been built. That is always suspect. For example, the zero-emission train (the Independent https://www.independent.co.uk/news/world/europe/germany-unveils-zero-emissions-train-only-emits-steam-lower-saxony-hydrogen-powered-a7391581.html) running on hydrogen is obviously not zero emission: hydrogen on planet Earth is all burnt already, so to produce it we have to burn something the traditional way. “Zero-emission” then refers to the very “modern” principle that there are no emissions in Germany where the train will run, but on the other hand there will be lots of emissions in those countries of the third world where we use to throw our dirt, as if under the carpet.

So, as you see, each thermodynamic cycle that closes opens up one or many other cycles.

Finally, a more philosophical consideration: Now that I’m all into Bruno Latour, and in particular I suggest “We have never been modern”, I realize that the individual cycles we talk translate into what are called the pneumatic facts by Boyle, and that the interlacing of cycles are Latour’s “hybrids”. In this sense, this conference is “a celebration of hybrids…”.
Nicola ArmaroliThe Energy Transition

80% of the world energy consumption is still sustained by fossil fuels. Solar is growing fast. He proposes an interesting analysis of consumption in terms of energetic slaves, that is, how many humans would be needed to do the same thing (a concept from Ivan Illich). An airplane requires 1.6 milion slaves. These slaves are the carbon-carbon and carbon-hydrogen bonds of the hydrocarbons. People often think that energy is expensive. But that’s not true, fuel is even cheaper than water – and it includes a lot of taxes. Debate is mostly focused on electrical energy, but 25% is electricity consumption and 75% are fuels. There are at least two kinds of oils: the “easy one” of Saudi Arabia that literally pours out. And now we are moving towards the non-conventional oil. In one hour the sun gives the quantity of energy that humans use in one year. Sun is versatile.

Today the sun produces 2% of world energy. In italy 7%. photovoltaic is mostly silicium. Wind power in the world is equivalent to 150 nuclear plants. It has never happened in history that some simple transitions like this was this fast. Transportation is the main leverage for the energy transition. From harvesting 1m^2 of rapeseed for one year in one’s backyard, one runs the car 2km. From 1m^2 of a panel for one year on one’s backyard, one does 500 Km. Choices have to be technically informed by numbers.

The bottlenecks of the energy transition. Would it be possible that we all go by electric car, as regards the materials? Suppose we can all buy a Tesla S. 80 TWh of energy consumed in Italy. It’s actually very little. It’s not the problem of the amount of electricity to all go by electric car. The problem is that we would need 20 times the world extraction of Lithium, just for Italy.
Gianluca Ruggieri, Consuming less to produce better – The energy transition and us

Starts with the Mononoke princess, representing the conflict between the city and the forest [again, interesting link to the beginning of “We have never been modern” on the separation between man and nature]. The spirits of the forest fight back the city because of the use of wood. The age of wood finished when wood finished. Between the ‘700 and the ‘800 they moved to carbon, which before was considered to provide “bad smoke”, as described by Charles Dickens in Hard Times. The British cities are made around coal.

Next: Motown, the name of Detroit, the capital of the auto industry. The American cities are made around cars.

Now: Freiburg, Solarsiedlung. It’s easier to go by bike than by car. The houses are all exposed south. And you cannot move by car. The objective in Switzerland is to reduce to one third of the energy consumed today. The proposal came from a green politician, it was opposed, they a referendum was held and the pro-green policy won (citizens were more responsible than politicians). Germany has as objective the 50% of energy consumption by 2050, especially in buildings 80% less than today. In France they want to reduce nuclear by 50%.

He mentions that he has a collection of energetic scenarios built in the past and they were wrong. They are not meant for prediction, but for understanding.

Italy imports 3/4 of the energy. Energy efficiency requires a lot of human work, so it’s also virtuous from that point of view.

How do we use energy in the house. Most of the energy that we use is for heating. We disperse it through walls, windows, or ventilation. In a typical ’70s house in Italy most of the dispersion is through walls. NZEB (“nearly zero energy building”) is now the standard in Lombardy, if you start from zero you have to build it like this. For ventilation, the air from the inside pre-heats the air from the outside.

“Il futuro non è più quello di una volta”.


Alicia Valero Delgado, Materials for the future in the energy transition

– Thanatia and the Second Law of Thermodynamics

An hypothesis about an Earth where all concentrated energy resources have been exploited and dispersed in the crust. We have to understand and know where we are in this process. The equilibrium state of life is death. If you don’t do anything to the system it will degrade. Everything that is different from the dead environment has “exergy”, which is a measure of the quality of energy. The “exergy” or “utility” of resources allows to put everything into the same units and it allows to compare things.

An “equilibrium” approach to thermodynamics. The sun allows directly or indirectly to regenerate that which has become degraded. So the question is “Are we approaching Thanatia? And at which rate?”.

– Towards a green energy transition?

ITC <-> Gold, tin, niobium, tantalum
Biomass <-> phosphorous
Wind <-> permanent magnets Nd, Dy, Pr, Sm and Co (rare earths, critical if we want to have wind power that has little maintenance, which is crucial if we want to have the wind power offshore)
Photovoltaics <-> In, Te, Ga, Ge, As, Gd
LETs and screens: Y, Eu, Tb, In, Sn
Batteries: <-> Ni, Mn, Co (absolutely critical!), Cd, La, Ce, Li
Electric vehicles <> La, Imanes permanents

“Multicolor economy”, not green! because we are going to use a lot of the periodic table. From here to 2020, 2030, 2040 etc. exergetic analysis of the energy transition. -25% less exergy in terms of fossil fuels, and +16% exergy more in raw materials.

Conventional power plants do not need rare materials. Which is more efficient: the old light bulb (tungsten, aluminum, glass, that’s it), the fluorescent, the LED is 10X more efficient. The fluorescent was a horrible idea. The LED is good.

You have to consider the quantity in the crust, and the energy required to extract, which increases exponentially the rarest the materials will become. As regards copper, in ten years 30% copper extraction more, but 46% energy cost of extracting copper.

They have assessed supply risks from a physical/geological point of view. We defined a risk scale. High: cumulative demand 2016-2050 > availability. Medium: there is a momentary difference between supply and demand.

Very high risk: Ag, Cd, Co, Cr, Cu, ga, In, Li, Mn, Ni, Pb, Pt, Te, Zn.

Lithium availability: Hubbard-sort of peak. The peak depends on what is in the ground, and no one know exactly what it’s in the ground. And even in the most optimist assumption the peak is just a few decades away.

The case of phosphorous is also problematic, because it exists but it is localized: most of it is in Western Sahara (I didn’t know this). The green oil: it cannot be replaced, and it is absolutely necessary for agriculture.

Today, mining is between 8% and 10% of the world energy consumption.

We need to recycle more, because at the moment is really bad.


– Towards a circular economy?

Share, repair, etc. Circular economy for everything? How to reuse tiny microparticle in cosmetics, in paintings, in the etc. Is the cure worse of the disease? Circular economy is impossible, we call it “spiral economy” because everything gets degraded in any case.

The value of durability. We have to increase the diameter of the spirals.

It is fashionable to say. We are developing great materials through the mixture of great materials: metal mixology. We need a global assessment of how it is expensive to separate them back.

reducing consumption, dematerialization, substitution of critical raw materials, and increase of the spirals.

Matteo Zuin, For a carbon-free energy: research in thermonuclear fusion

“It’s important to understand that in physics we have absolutely no idea of what is energy…”

R. Feynman.

[my opinion: Energy is conserved. It’s the other way around! That which is conserved, that’s energy. It’s not a law, it’s a definition!]

[I couldn’t take notes here because of low battery.]


Students of the high schools

Two students from scientific high schools. Our carbon footprint.

Surface of wood surface necessary to absorb the carbon dioxide.

62% of Km is car alone. 33% in two people.

We need to consider numbers to take sensible decisions.


Fabio Di Menna, Energy ad food systems: waste and opportunities

The relationship between food and energy is even intrinsic to physical units. The Joule is the energy necessary to raise an apple by one meter. The calorie is necessary to heat water.

Food energy and drinkable water are three aspects that cannot be separated.

Waste: food that is thrown away but that is edible. 33% of the world production is wasted.

world BALANCE (2014) Diagram of Sanct….??? Very interesting diagram.

When we talk about energy we also need to talk about equity. OECD countries use mostly fossil, Africa mostly biomasses.

They considered a comprehensive energy balance of milk produced in Missouri USA and in Emilia-Romagna in 15 farms… We have more energy input for the industrial production of food than there is inside the food itself. They considered energy in working and packaging salad according to different branding necessities.


The problem with incentives
Marco Grasso, Climate policy and consumption-based carbon accounting

He starts saying that his argument is more theoretical, abstract, and less “sexy”. With the Paris meeting countries made some pledges declaring what they intend to do in terms of nationally determined contributions. This is contrary to the Kyoto protocol to pretend to say how countries should have done the transition, a very top-down approach. The unit measure of emissions are measured in terms of the production of the emission of those goods and services that are produced. This is often made in Taiwan, and made in China etc. 2°C is sort of the unanimously considered the boundary (without scientific arguments, a bit naive). Even in the better of hypothesis Paris brings us beyond that. Hurricanes enter the discussion. Some thinkers believe catastrophes are needed to take action. The acceptance of responsibility has slowed down the reaching the compromise, and the compromise is very modest.

What could unblock, or favor to go beyond Paris before the “global stocktake” in 2023. He proposes to pass from emission basing on production bases accounting (PBA) to consumption based accounting (CBA), there already exist databases from the second half of the ’80s (it is not a problem of measurement). The advantages would be in terms of equity (the countries that have polluted more would pay more), efficacy (it would stimulate international collaboration), and more politically doable.

An example: sharing the carbon budget. He and a coauthor published on Nature Climate Change trying to look at what would happen. We Europeans have off-shored our productions via colonialism.


* We should also make sure that the cycles that we open are not much bigger and expensive that the original one. Unfortunately assuming the opposite is a quite realistic attitude, as notes Fukuoka in his The one straw revolution.

** Even assuming that technologies could be invented to invert the chemical reactions that occur (for the most part) in the production of energy, and even assuming that we become so smart to produce very cheap and ecological technologies in this respect, I’m actually skeptical of the theoretical possibility of using the sun as the only source of both the energy input and the technology. If that was the case, we would have a “no-cradle-to-cradle” theorem… In this respect, it would be interesting to study wether “nature alone” (that is, that thing that was running basically up until the industrial revolution) did the whole thing just using the sun, or there was some “linear” (though minimal) consumption of earthly resources.





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