"Energy slave" is a term coined by Buckminster Fuller in 1940 to draw attention to fossil fuels, the invisible workforce that enables our modern lifestyles and technology. Just like the human slaves of past eras, these energy slaves will one day stop working for us, and when they do, our entire system built upon them will collapse. Nate Hagens calculates that: > 98% of physical labor in the modern world is done by machines which in turn are 85% powered by energy dense carbon compounds.  Few think about it, but 1 barrel of crude oil, at 5.8 million BTUS, for which we currently pay $70, contains the work equivalent of 4.5 years of human labor, for which we pay (in USA) $140,000.  The average American uses 54 of these ‘barrels’ per year directly, with an additional 10-20 via imported goods, equating to ~300 ‘fossil slaves’ supporting our lifestyles. - https://www.resilience.org/stories/2018-05-08/where-are-we-going/ How would we feel knowing that we require the equivalent of 300 human slaves working for us year-round in order to sustain our lifestyles? That thought alone should motivate us to begin downscaling our energy needs. After almost two centuries of living off the backs of our energy slaves, we need to begin emphasizing the value of human physical labour once more. This might seem to be an extreme view. After all, can't we replace fossil fuels with nuclear power, or wind and solar energy? And in the worst case scenario, can't we go back to using animals for labour? There is good reason to believe, however, that none of these alternatives will lead us towards gradual descent instead of collapse. In their book How Everything Can Collapse, authors Pablo Servigne and Raphaël Stevens give a lot of data points which support this view. One important number is something called Energy Return on Investment (EROI), which measures the relation between energy produced and energy invested. This is important because extracting energy always requires some expenditure of available energy, and we can only use the surplus for other activities, such as powering our cars and smartphones. The authors explain: > At the beginning of the twentieth century, US oil had a fantastic EROI of 100:1 (for one unit of energy invested, one hundred units were recovered). You hardly needed to start digging before the oil started gushing. In 1990, it had fallen to only 35:1, and today it is about 11:1. As a comparison, the average EROI of the world production of conventional oil is between 10:1 and 20:1. In the United States, the EROI for oil sands lies between 2:1 and 4:1, that for agrofuels between 1:1 and 1.6:1 (10:1 in the case of ethanol made from cane sugar), and for nuclear power between 5:1 and 15:1. The EROI for coal is about 50:1 (in China, 27:1), for shale oil about 5:1 and for natural gas about 10:1. All these EROIs are not only declining, but declining at an accelerating rate since it is always necessary to dig deeper and deeper, go further out to sea and use ever more expensive techniques and infrastructures so as to maintain the level of production. Think, for example, of the energy that would be needed to inject thousands of tons of CO2 or fresh water into ageing deposits, and the roads that would need to be built, and the kilometres that would have to be covered in order to reach the remote areas of Siberia … > – Servigne, Pablo; Stevens , Raphaël. How Everything Can Collapse (pp. 32-33). Wiley. Kindle Edition. The situation isn't any better with renewable energy: > In the United States, concentrated solar power (those big mirrors in the desert) produces a yield of around 1.6:1. Photovoltaics in Spain produce around 2.5:1. As for wind power, it initially seems to offer a better yield of about 18:1. Sadly, these figures do not take into account the intermittent nature of this type of energy and the need to back it up with a storage system or thermal power plant. If we take this into account, the EROI for wind turbines comes down to 3.8:1. Only hydroelectricity apparently offers a comfortable yield of between 35:1 and 49:1. But besides the fact that this type of production seriously disrupts natural habitats, a recent study has shown that 3,700 projects underway or planned across the world would increase global electricity production by only 2 per cent (from 16 per cent to 18 per cent). > – Servigne, Pablo; Stevens , Raphaël. How Everything Can Collapse (p. 33). Wiley. Kindle Edition. And here is the conclusion to the argument: > The problem is that our modern societies need a minimum EROI to maintain all the services currently offered to the population. The principle of energy use is roughly the following: we first allocate all the energy surplus we have to the tasks essential for our survival, such as food production, building and heating our habitats, making our clothes, and running health systems in the cities. Then we split the remaining balance between the systems of justice, national security, defence, social security, health and education. Finally, if we have any energy surplus left, we use it for our entertainment (tourism, cinema, etc.). > > Today, the minimum EROI to provide all of these services has been assessed as within a range of between 12:1 and 13:1. In other words, there is a threshold beneath which we should not venture unless we are prepared to decide collectively – and with all the difficulties that this implies – which services are to be maintained and which it will be necessary to give up. With an average EROI in decline for fossil fuels, and an EROI of no more than 12:1 for the majority of renewable energies, we are coming dangerously close to this threshold. > – Servigne, Pablo; Stevens , Raphaël. How Everything Can Collapse (p. 34). Wiley. Kindle Edition. --- Resources: Australian artist Stuart McMillen has done some great comic explainers and essays on: - [energy slaves](https://www.stuartmcmillen.com/comic/energy-slaves/#page-1) - [energy return on investment (EROI)](https://www.stuartmcmillen.com/blog/energy-slaves-reflections-4/)