The Return of the “Double Exponential”

For the first time in 20 years we are seeing the re-emergence of the “Double Exponential.” The Double Exponential occurs when energy consumption growth not only reflects exponential growth in population, but also exponential growth in per capita energy (or oil) consumption. By plotting world energy consumption along with world population, we can see that energy growth outpaced population growth until the oil crisis in 1973 (actually this relationship had been true for a long time previous to the oil crisis). Growth in both per capita energy consumption and in population boosts energy growth and hence the “Double Exponential” curve.