Energy Consumption and Income: An International Panel Smooth Transition Model of the uznets Curve

This paper investigates the potential threshold effects of the relationship between per capita Energy consumption and national income. Using a panel threshold regression model، we derive country-specific and time-specific income elasticity for 13 OPEC countries over the period (1980–2008). The results show that the income elasticity of energy consumption for these countries is less than 1. Furthermore، the relationship between energy consumption and income seems rather nonlinear، changing over time and across countries. We see a fall of elasticity when the income level increases. More precisely، it is an inverted-U-shaped curve، indicating that the fall is more important when the income level is relatively high.