The entropy law and the impossibility of growth

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In the debate about whether economic growth can be sustained, the most popular answer is that technological progress will always find a solution. Renewable sources of energy, electric cars, and “smart” solutions are believed to be already paving the way for a greener future. The concept of circular economy, which claims that every waste could become a resource to fuel forward the economic process, is also gaining in popularity.

However, the majority of economists of today, despite their claim to follow science and reason, still seem to deny ones of the most fundamental laws of physics – the laws of thermodynamics. These are laws that do nothing less than rule the functioning of the physical world, matter and energy. As the economic process is based on interactions with matter and energy, it is impossible to take out the natural resources out of the economic equation.

Let’s first start with pure science

First of all, it is important to remind you that in a closed system, energy and matter cannot be created. They can only be transformed and their quantity always remains constant. This is the law of conservation of energy – the first law of thermodynamics. We can define a “closed system” as a system with no interaction of any kind with the environment outside the system.

Earth is theoretically not a closed system but at a human scale it is almost closed except for two cases:

Regarding matter, we sometimes receive meteorites from space. But the quality and the quantity that we receive make that extra matter irrelevant for the economic process.

Regarding energy, the only one we receive from out of Earth is solar energy (in a very abundant quantity). As we will see later, this has very important implications for our modern economies.

That being said, let’s jump on the second law of thermodynamics – the law of entropy.

First, what is entropy? The Webster’s Collegiate Dictionary (1948) gives the following simplified definition: “a measure of unusable energy in a thermodynamic system”. In France, the Larousse Dictionary (1975) says more simply: “a scale that allows to estimate the degradation of energy in a system”.
Looking at it from a human perspective, energy can have two states: usable and unusable. For example, coal is usable energy because a man can transform it into heat or mechanical energy. When coal is burned, its chemical energy remains constant. But its usable energy or free energy has been transformed into unusable or linked energy in the form of heat, smoke, and ashes.

When the amount of unusable or linked energy increases, it is said that the entropy increases.

And according to the law of entropy: “In a closed system, entropy always increases irreversibly”.

In practice, that means that energy and matter keep degrading. It is the fundamental reason why, with time, food gets spoiled, our houses will fall apart, our tools and machines will eventually break down, and… we will all die one day. Nothing is permanent. When it comes to energy, that law means that every transformation of energy (from chemical to mechanical, for example) creates thermal energy (heat) and that heat can never be converted back into another form of energy (in a closed system).

It is because of this law that you can never form an ice-cube from melted water without an additional input of energy. Similarly, you can never make a new car wheel from the particles that got detached off the wheel from friction. The wheel is forever degraded and the particles forever lost (to us). The wheel can never be made new again without an external input – new matter and energy. In the examples above, the piece of coal, the ice-cube, and the wheel are said to be in a state of low entropy, while their degradation creates a state of high entropy.

Why is the law of entropy a problem for our modern economies?

Fortunately for us, the sun is there to slow down Earth’s entropy increase. The constant additional energy input from the sun allows living organisms to sustain and perpetuate themselves. In theory, if the ecological conditions remain the same on Earth, life can thrive until the Sun ends.

However, our modern economies are energetically only marginally dependent on the Sun. Energy inputs mostly rely on extracting and mining fossil fuels and minerals, such as coal, oil, gas, uranium, sand, various rocks, metals, and rare earths. For example, 78% of all electric power today is generated from fossil fuels. Even solar panels need for their construction extracted raw materials, such as rare earth. These resources are renewed in such a long period of time that they are considered from human perspective non-renewable.

This causes a very big problem of sustainability of our modern civilization.

For example, agriculture, the foundation of civilization, is today highly dependent on fossil fuels for fertilizers, pesticides, and machines (plowing, processing, packaging, transporting). When we eat a salad, we no longer eat the product of solar energy (sun for the plant to grow, sun for the growing of food necessary for the farmer to have energy to farm). We “eat” a mix of solar energy and fossil fuel energy. The same logic applies for modern medicine. In fact, Joseph Tainter, anthropologist and author of The Collapse of Complex Societies in 1988 considers that ⅔ of humans today are alive because of oil.

A popular solution comes from recycling. However, the process of recycling requires a high amount of energy and resources, and therefore its benefits are only marginal.

As shown by Grosse (2010), in an economy where material consumption increases, recycling can only delay resource depletion. The author takes the example of steel, the best-recycled material worldwide. At a current 62% recycling rate and with a yearly rise in consumption of 3.5%, recycling is only delaying depletion by 12 years. If we keep consumption rates steady, even increasing recycling rates to 90% would only add an extra seven years before depletion.”(European Environmental Bureau (EEB), 2019)

EEB also explains: “Since materials inevitably degrade through time (2nd law of entropy), they can only be recycled into the same products for a limited number of times before they have to be used to produce other products with lower “quality”. Put another way, sooner or later, any recycling is necessarily downcycling”.

The process of degradation of energy and matter is naturally happening constantly. But the human activities, dictated by the necessity of exponential economic growth, accelerate this process to such an extent that solar energy is not enough to compensate and limit the entropy increase.

The problem is, the amount of accessible matter on Earth is limited. Even if matter is present in astronomical quantities on Earth, only a small portion is accessible and not everything is relevant for the economy. Everywhere on the planet we are being confronted with diminishing returns. That means that we need to make more and more effort in order to extract less and less resources.

The solution is therefore to get rid of our dependence on energy and matter coming from fossil fuels and other minerals, and relink the civilisation as much as possible to the abundant energy of the Sun and sun-dependant sources of matter, like wood. This is the physical condition for a sustained long-lasting human life on Earth. The other option, continuous growth, will inevitably decrease humanity’s capacities to survive in the lung run. However, relinking our civilisation with the Sun implies a development that does not exceed the speed of the natural cycles. For materially rich countries, it therefore means a degrowth of energy production and consumption. For poor countries, this means to grow just until a certain limit. For every country on the planet, it is necessary to define and aim for a steady-state economy. Only such an economy could really succeed in “meeting current generation’s needs without compromising the ability of future generations to meet their own needs” (official definition of sustainable development).

With time, a growth economy inevitably leads to the collapse of our civilization and the threat of climate change today even means the potential collapse of Earth’s ability to sustain life.

In conclusion, the laws of thermodynamics pose a question to humanity. On the one hand, mankind can have a very short life but exciting and extravagant (for a minority, mainly rich people) thanks to the rapid depletion of resources’ stocks and degradation of the environment derived from extractive and processing activities. On the other hand, we could collectively choose a very long life by reducing the pace of extractive activities to the minimum. For a modern man busy with futile activities dictated by advertisements and competition that means choosing a life that seems to be more monotonous, physically more demanding, and less exciting. In reality, the degrowth perspective aims to build an economy of “enjoyment of life” (Nicholas Goergescu-Roegen) or “frugal abundance” (Serge Latouche) in which humans get a new sense of community living and take more pleasure from caring and being (spiritually growing) than accumulating goods (spiritually regressing).

This text is inspired by the 2006 augmented French edition of the book “The Entropy Law and the Economic Process”, 1971, from Nicholas Goergescu-Roegen.

Note: Nicholas Goergescu-Roegen himself was not very happy with his own conclusions, aware that they could hardly become popular. He clearly put out of question the idea of a return to the caves (or to the trees) and wrote a series of general recommendations:

  1. Eradicating war and the arms industry,
  2. International help from the rich countries to the poor countries,
  3. Population reduction and control,
  4. Fighting against energy waste,
  5. Limiting the industry to produce just what is necessary,
  6. Ending with “fashion” that pushes us to throw away usable products,
  7. Restructuring the industry to produce durable and repairable products,
  8. Slowing the pace of our lives to allow for more time used in an intelligent manner instead of futile activities.

In his book, he also briefly criticises the use of nuclear energy on the basis that it generates heat pollution, disturbs rivers ecology, and it allows for the development of other harmful industries. For a critic of mass energy production, you can read our article inspired by books from Ivan Illich: Energy, Equity, and Democracy.