Energy Slave

An energy slave is that quantity of energy (ability to do work) which, when used to construct and drive non-human infrastructure (machines, roads, power grids, fuel, draft animals, wind-driven pumps, etc.) replaces a unit of human labor (actual work). An energy slave does the work of a person, through the consumption of energy in the non-human infrastructure.

The term was first used by R. Buckminster Fuller in the caption of an illustration for the cover of the February 1940 issue of Fortune Magazine, entitled "World Energy". Alfred Ubbelohde also coined the term, apparently independently, in his 1955 book, "Man and Energy", but the term did not come to be widely used until the 1960s, and is generally credited to Fuller.

An energy slave is used to compare the productivity of a person and the energy that would be required to produce that work in the modern, oil fuelled industrial economy, although it could be applied anywhere that labor is produced with non-human sourced energy. It does not include the ancillary costs of damage to the environment or social structures. Formally, one energy slave produces one unit of human labor through the non-human tools and energy supplied by the industrial economy, and therefore 1 ES times a constant that converts to work accomplished = 1 human labor unit.

The choice to “employ” energy slaves is only at the margins of their total impact, so are called slaves because users receive the value produced by them as an entitlement of the society.

One way to look at an energy slave might be called the “macro” view. This is to look at the total flow through of energy divided by the number of persons being supported by the infrastructure where that energy is being used. It is a number that can change instantaneously as the flow through of energy changes. Although this formulation is challenged by the need to decide whom to include in the count, and the massive data-keeping it would require, it is intuitively simple because we merely divide one number by the other, and guides us in thinking about the other perspective. It is suited to large blocks of a given economy and to comparisons of economies.

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