The Entropy of Cities Part 1

At a recent visit to the home of a client, our host, while touring us around his property, noticed a screwdriver on top of a windowsill.?He immediately called the attention of one of his househelp to put the misplaced tool to its storage.?He then explained to his guests that he takes immediate action even on small things like that to avoid them from growing into larger states of disorder, even citing the 2nd principle of thermodynamics.?I was quite impressed with the analogy. He was right, after all.?In an open system, things will tend towards increasing disorder, as physics tells us. The principle applies to every aspect of life and the known universe. As physicist Adam West said, “To maintain order and structure in an evolving system requires the continual supply and use of energy whose by-product is disorder”.?

?The incident had me contemplating about entropy and the metabolism of cities.

?A city is an open system which can exchange both energy and matter with its surroundings. Like biological organisms, the organization of cities is maintained by a constant input of energy and is offset by an increase in the entropy (disorganization) of the surroundings, through the emission of heat, waste, and pollutants.?The flows of energy and material absorbed by an urban area are transformed (metabolized) into productive and more complex output (goods, information, social structures) and are also used to sustain order within the system and avoid?degradation (entropy).?This continuous input of energy and resource through the system enables a city to thrive amid its increasing complexity.

Our Insatiable Demand for Energy

Societies and human organizations multiply an individual’s productivity by orders of magnitude.?This is the reason for the existence of cities—compounding human productivity to create material wealth and prosperity for many.?This attribute comes at a cost, however, in the form of energy input.?Our individual biological need for energy is only about 2,000 calories per day, or about 100 watts--the equivalent amount of energy needed to power a light bulb.?We now live in an evolved society, however, that requires us to not just satisfy our biological metabolic requirements but to also sustain our social metabolism.?On average, a typical person now needs about 3,000 watts per day to sustain his lifestyle--using tools, vehicles, and gadgets with embodied energy. The average person is effectively using 30 times more energy than what he naturally needs. But this is only a global average. A person living in a wealthy country such as the United States consumes about 11,000 watts per day, using energy that has been processed to produce the things that sustain our modern life. Progress and prosperity come with a big energy price tag.

?But the transformation and consumption of energy is just one side of the thermodynamic coin.?The second law states that the inevitable consequence of transforming energy into useful work and in maintaining order within a system is that it produces useless, disorganized by-products of waste and heat in the process.?Disorder inevitably accompanies growth and change.

?Natural systems have evolved to extract near-limitless energy from an external source (the sun) and to process wastes in a closed loop where byproducts are consumed by other organisms within the ecosystem, thus achieving a low entropy state.

?Man’s discovery of fossil fuels led to the extraction of finite internal energy sources to supply the vast quantities of energy required by modern society. The sobering reality is both the extraction of energy and the production of waste (pollution, carbon emissions) are happening at a rate and volume beyond the capacity of natural systems to recharge and assimilate.?This is the reason for the concurrent crisis of fuel scarcity and climate change that we are facing. We have, effectively, accelerated entropy.

Is there hope?

?Are we therefore in an accelerating and irreversible descent into disorder and chaos? While there is no escaping the laws of physics, we can shift from our state of high entropy towards one of lower entropy.?For one, we can shift sourcing our energy from our internal finite carbon stocks towards the more abundant external sources such as the sun. We can create new tools, buildings and transportation systems that will be less energy- and material-intensive. We can change our linear systems of production and consumption to more circular models, emulating the closed cycles of nature. We can be less consumptive and less wasteful.

?It will take a tremendous leap and a conscious effort to build a low-entropy society. It will require leveraging the collective innovation and knowledge that cities are good at producing to transform nearly every aspect of modern civilization. And just like the misplaced screwdriver, the best way is to confront the disorder sooner rather than later.

Original article published in the Philippine Daily Inquirer, August 2022