A 60-YEAR RECORD OF THE DEMOTECHNIC INDEX OF STATES, 1960-2019
DI = (ET - EM)/EM
Where ET represents the total annual energy used (KJ/y), and EM represents the metabolic energy demand of a population (KJ/y). Therefore, DI is the scalar multiple of energy used by a state over the quantity of energy required for simple human survival on a per capita basis. The DI was calculated for all fifty states in the U.S from 1960-2019 and serves to measure the “energy intensity” of states and a proxy for energy sustainability of each state. DI values range from 2,127.03 for NY in 1973 to 4.69 for Vermont in 2016. High DI values are associated with populous states coupled with low renewable energy utilization. The long-term (multi-decadal) trajectory of the DI for each state shows their progress toward or retreat from energy sustainability. States with large contributions from renewable energy sources (especially hydroelectric power) display markedly lower DI over time, regardless of overall DI trajectory. The DI highlights states’ overall energy efficiency, dependency on non-renewable energy resources, and the impact of renewable energy sources on prospective energy sustainability. As such, the DI is an easily comprehensible measure that could be adopted to articulate sustainable energy practices.