Inequality and energy: Revisiting the relationship between disparity of income distribution and energy use from a complex systems perspective

To consider the impacts of economic inequality on energy consumption efficiency we need indicators that take into account the complexity of the economic and energy systems. We also need decision support tools that help incorporate such indicators into policy analysis. Drawing inspiration from urban studies and ecology, in this paper we develop a scaling indicator for income disparity in national economies that is a measure of system complexity and does not presuppose any distribution as ideal. The scaling indicator is calculated for 2010 income distribution data for countries. We show that rising disparity - measured using this indicator calculated; a) for distributions of incomes across consecutive twentieth percentiles of population in national economies and; b), for distributions of population density in census blocks in metropolitan statistical areas affects energy consumption efficiency in a diametrically different manner in cities and nation states leading to a higher urban carbon footprint while increasing energy efficiency nationally. The different nature of these two systems explains the results. We then modify tools for visualizing complexity from urban studies and ecology to explore the correlation between income disparity and energy efficiency in national economies.