young kid with food on his chin

Sustainability and energy | Feeding everyone is basic thermodynamics

Humans are needy because we cannot risk the failure of our chemical engines. Now there are so many of us sustainability and energy are intricately linked.

The standard definition of sustainability runs along the lines of meeting the needs of the present without compromising the ability of future generations to meet their needs which is only possible with sustainability and energy but may also be impossible with it. 

Food, water, and shelter are essential to human life. Fail to obtain one or more of these fundamentals and the complex chemical engine that is our body succumbs to entropy and we die. 

In modern times we also need each other because no one person has all the skills to gather enough food, water and shelter and avoid the perils nature coughs up. 

We all need help.

Neediness that becomes a handicap sending a person to a therapist is an expression of this fundamental reliance on each other. We function well together because our solution to defy entropy is creating innovation and technology to gather and exploit nature’s resources. This is best done in groups or, if you prefer, teams.

Our neediness is an expression of human success.

Is neediness sustainable?

Can we carry on being needy? 

We could all transcend to the virtual mountaintop and meditate away our egoic selves to leave our needs behind. Then death would stalk us all, because human life is only sustained with food, water, and shelter. 

Even the monk on the mountaintop has to eat and drink. He also can’t Wim Hoff his breath through a blizzard expected on mountaintops. He’ll need some shelter. 

As we have seen, meeting these fundamental needs for 8 billion people is a 22 trillion calories-a-day task—an sustainability and energy problem.

This is not how sustainability is defined. 

The standard definition of sustainability with the most traction is “Meeting the needs of the present without compromising the ability of future generations to meet their needs”, which shortens to profit, planet, and people. 

This could be about sustainability and energy, but instead, it tends to be about the broader use of resources that generate profit.

Thermodynamic definition of sustainability and energy

Meeting human needs is ultimately an energy transfer. 

Staying alive requires energy because the organisation of cells and chemistry in the body is not thermodynamically the natural state of matter. The organisation of cells and organs takes energy to maintain the complexity. The endogenic energy from food for metabolism is more achievable with access to shelter in the cold winter.

So here is an alternative definition for sustainability with energy in mind 

“A cyclic process is sustainable if and only if (i) It is capable of being sustained, i.e., maintained without interruption, weakening or loss of quality ‘forever,’ and (ii) The environment on which this process feeds and to which it expels its waste is also sustained forever.”

Patzek, T.W., 2004. Thermodynamics of the corn-ethanol biofuel cycle. Crit. Rev. Plant Sci. 23 (6), 519–567.

This sustainability and energy definition better reflects the truth that for a system to keep functioning, it has to be fed and cannot deplete the sources of the inputs beyond their capacity to replenish. This applies to human bodies, all pother organisms and the ecosystems they inhabit. It also applies to human social systems.

Although closer to sustainability and energy than the anthropocentric profit, people and planet, this thermodynamic definition has some implications.

  1. A cyclic process cannot release waste chemicals into the environment, i.e., its net waste production must be close to zero “forever”, or the context is altered, and the cyclic process weakens or loses quality
  1. A sustainable cyclic process cannot release heat into the environment at a rate too high for the Earth to export to the universe; otherwise, the environment warms. 
  1. A requirement to define “forever” given that in perpetuity fails to understand nature. Patzek chose a timeframe shorter than forever, 5,000 years for human civilisation, the age of Egypt’s oldest surviving wood structure.

What humans do in this version of sustainability and energy is turn the sun’s current and ancient energy stored temporarily in plants and livestock or for longer in fossil fuels into people—as of late 2022, 8 billion chemical engines that are converting biomass energy into heat and using a whole lot more to make that experience as comfortable as they can.

What we forget is that the energy pulse from fossil fuels is vast. The extra people we made from it is somewhere between 4 and 6 billion more than photosynthesis can support.

Feeding everyone alive will need an energy subsidy to channel extra photosynthesis into food. 

young mixed-race boy eating a cake to feed his chemical engine—a test of sustainability and energy

Is basic thermodynamics sustainable?

Almost everything humans do is unsustainable because all significant human activities are linear and irreversible—mining of minerals, oil, gas, coal, soil, groundwater, ecosystems, biodiversity, etc. 

We are not good at cycles.

Humans also dump toxic chemicals everywhere in the environment (atmosphere, water, and land) that change the cycling conditions. And keeping the thermodynamic theme, one of the primary pollutants—greenhouse gases—also makes it harder for the excess heat to escape into space.

Everyone knows all this after just a moment of consideration.

The stuff that we buy, including food, comes from somewhere else, is consumed by us, and then thrown away or flushed down the toilet. It leaves us to go somewhere else. 

Maybe we think that a landfill is just a hole in the ground that the garbage trucks fill up or that the sewer takes waste and miraculously cleanses it at the water treatment plant.

It doesn’t. 

Current human actions put sustainability and energy at odds. Energy use is biologivcally inevitable. Only we have added exogenous energy from fossils to turbocharge resource use. The energy needed to make all the goods and provide all the services demanded by humanity generates waste as physics dictates.

Just ask the oceans what they think about plastic.

no scientist can claim that the human economy is sustainable

Bolson, N., Yutkin, M., Rees, W., & Patzek, T. (2022). Resilience rankings and trajectories of world’s countries. Ecological Economics, 195, 107383.

What sustainably FED suggests

Neediness is the human condition.

We are needy beings because, at a primal level, we have to find fuel to maintain our chemical engines, or we die. 

But there is more than basic metabolism in our sustainability and energy story. Humans fine-tune our miraculous talent for resource use to make our lives more comfortable because physical comfort is easier on the body’s chemical engine. 

No matter that comfort is corrupted by the drive to achieve it and we don’t know when to stop adding more comfort. And this neediness is insatiable. It will not go away.

Then we found fossils as a miraculous external energy source and set about converting that energy into more people. That pulse of extra people, several billion of them, who are here, because we tapped an external energy source, makes sustainability and energy impossible without 1) maintaining an eternal energy source and 2) curbing our neediness. 

Our best sustainability and energy hope is to find another clean energy source to keep the human engines running until neediness is mastered and our population declines back to the limit imposed by planetary boundaries.

Wish everyone luck.

Science Source

Bolson, N., Yutkin, M., Rees, W., & Patzek, T. (2022). Resilience rankings and trajectories of world’s countries. Ecological Economics, 195, 107383.

Hero image from photo by Marcus Neto on Unsplash


Mark is an ecology nerd who was cursed with an entrepreneurial gene and a big picture view making him a rare beast, uncomfortable in the ivory towers and the disconnected silos of the public service. Despite this he has made it through a 40+ year career as a scientist and for some unknown reason still likes to read scientific papers.

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