Review: Energy Return on Investment by Charles A. S. Hall

Hall invented the very term energy return on investment, and he’s done decades of seminal research on the phenomenon that it describes. As the current shale oil miracle goes the way of all mirages—causing the issue of energy depletion to reenter the public discourse in a big way—one can only hope that Hall’s ideas will draw a great deal of well-deserved notice.

What Future for the Anthropocene? A Biophysical Interpretation

The history of the earth system is normally described in terms of a series of time subdivisions defined by discrete (or “punctuated”) stratigraphic changes in the geological record, mainly in terms of biotic composition. The most recent of these subdivisions is the proposed “Anthropocene,” a term related to the strong perturbation of the ecosystem created by human activity.

Using Energy to Extract Energy – the Dynamics of Depletion

We now have to take into account that depletion means that, at well heads around the world, the energy to produce energy is increasing. It takes energy to prospect for oil and gas and if the wells are smaller and more difficult to tap because, for example, they are out at sea under a huge amount of rock. Then it will take more energy to get the oil out in the first place.

Measuring Energy Return on Investment at a National Level

Above all, the relevance of a national-level EROI lies in its potential to inform policy decisions that aim to manage an energy transition to a low carbon economy. In general, countries should aim to have high levels of national-level EROI, since this means that more net energy is available for use in the productive economy.

Is There Such a Thing as a “Net Energy Cliff?”

As societies and economies transition away from high net energy resources such as ‘conventional’ fossil fuels and towards lower net energy resources such as unconventional fossil fuels or renewables, either voluntarily (e.g. to fight climate change) or due to resource constraints, a number of researchers and analysts have argued that we might be approaching the “net energy cliff”…