Find yourself in your element!
Let sort out our Thermodynamics for a bit…
Hello! If you are reading this post it is because you are interested in simple explanations! When water froze last winter till the time the ice melted and paths reopened, Thermodynamics always was there. It is about time to sort it out! It may take us some energy, but all invested work has its rewards!
How does Thermodynamics connect with the Climate Emergency? I am Enrique García Franco, a chemical process engineer, and today we are going to talk about Thermodynamics. Typically, people feel scared, as relating it to complexity.
As its name suggests, Thermodynamics is the branch of Physics dedicated to the study of energy flow (Thermo + dynamics). As Homer Simpson would say, the world obeys the strict Laws of Thermodynamics. When we make use of the concept of Law in Science, it means they are universally present. Let’s look at the consequences of the Second Law in plain words.
We all know how complicated it is to manage a file directory. It is much easier to save everything on the desktop and call it “this one”. As is the natural tendency, time goes by and the clutter inside the computer keeps growing. What do you do then? You tidy it up! And for this, it is necessary to invest some effort in systemizing and renaming, so that they are easily accessible.
Well, right there, with a simple example, we have the Second Law of Thermodynamics, which tells us that within the computer (Universe), every action has a natural spontaneous tendency towards disorder. And, conversely, that gaining order is to fight against inertia, requiring effort (work).
Let us go now to the chemical world. To get started, let’s imagine a cyclist like the one in the GIF:
It comes naturally to him to go downhill, and on top of that, he does a cool pirouette. He can do it by following the natural tendency (henceforth on inertia).
However, anyone with a developed critical capacity would be shocked by this other reverse situation, where the cyclist climbs without apparent effort:
If we think in chemical terms, the mountain that the cyclist descends has its counterpart in the energy level G, which is known as Gibbs Free Energy. We imagine the cyclist at the top of the slope:
At the chemical level, what the Second Law of Thermodynamics tells us is that the reaction will advance down the mountain of the energy level G, following the natural tendency. In the jargon we describe the reaction as being spontaneous because it occurs without any external effort. In fact, we can take advantage of this situation and extract useful work from it. If we now consider the reaction
Carbon + Oxygen → Carbon Dioxide
This reaction from left to right is largely spontaneous. When oxygen combines with a fuel, the reaction is of the combustion type. We have all cooked at barbecues with the heat given off the by the campfire, as in the photo below:
While burning fuels is perhaps what the closest at hand, the first thermodynamists already warned us of the consequences we are already living today. If everyone burns to extract useful energy (cooking, heating, travel, manufacturing …), the big dilemma is that all the carbon dioxide released to the atmosphere. And there seems to be something wrong.
The accumulation in the atmosphere has a direct consequence on the average temperature of the planet, according to a mechanism known as the Greenhouse Effect. The graph below shows what happens to radiation as it passes through the atmosphere.
The ray of sunlight passes through the atmospheric layer, carrying energy from the Sun. When it is reflected at the surface, it loses some of its energy. Something has changed. Just then it encounters the atmosphere again, where it turns out that CO2 now interacts with ray and traps some of its energy upon reflection. The net result is a warming of the atmosphere, which is propagating around the planet, including the ocean currents and polar ice caps.
This effect, much to the chagrin of the denialists, is seen in the following graph. A direct correlation between increasing carbon dioxide levels and average global temperature is evident. Clear, isn’t it?
One might think that the trend is inevitable and that we are moving towards the end of an era. I, as an applied scientist, think not. The graph obeys a consumption trend. A life model. But what would happen if other considerations were considered when commissioning industry? Is there room for other concerns?
The answer to that has been given by Europe, although it has gone unnoticed in the COVID milieu. The models that are truly sustainable over time are those that bring together the so-called 3P´s: People, Profit and Planet. Their activity has a controlled impact on the environment, while generating an economic benefit that projects them into the future. In addition, the communities where they are located benefit from their implementation. Each of these three partners wins something from the implementation.
Although this might be thought typical of the world of management, it overlaps with Thermodynamics.
The cyclist must always go downhill, obeying the Second Law. But is that the end of the story? Is the Earth condemned to perpetually go down the hill? If we keep spending energy, is there any other energy input? In fact, yes! We orbit around a star, the Sun, which radiates energy to us. Among other phenomena, it perpetuates the water cycle, in which seawater is evaporated to form clouds and rain.
The Sun is our greatest ally in overcoming the tendency towards equilibrium. And this has already been noticed by several players in the chemical world. Let’s give a clear example.
Refineries typically harness crude oil as a business case. In order to do so, it is combined with a substance, not present in nature, named Hydrogen. Hydrogen is found in abundance when oxidized and is no other than plain water!
Bringing water to its reactive form to jump from there to value-added compounds, is energetically costly. It opposes the inertia of lowering G. But what would happen if this energy came from renewable sources? Can you imagine jet fuel with no carbon footprint? Well, combining green hydrogen with carbon dioxide happens spontaneously. Think of taking that CO2 from forestry waste. Net zero Carbon balance.
In conclusion, we have seen that the world is governed by the Laws of Thermodynamics, which categorically exist. Any spontaneous conversion must go down the slope of the energy level G. To raise it, useful work must be invested. But the Earth is not an isolated system, because we receive energy from the Sun. The combination of technology and the political will can help us to bend the carbon dioxide concentration curve in time.
Author: Enrique García Franco, LinkedIn, YouTube channel
This entry is a collaboration result within the Collective Intelligence Development Network stemming from the webinar, please check it on our YouTube channel. For the updates, connect us on LinkedIn!
