Abstract
Exploring the relationship between energy intensity and per-capita income for the period of 1981- 2015 in 42 countries has been targeted in this study. In order to achieve that target, the study has used the fixed effect model for these 42 countries. A non-linear relationship between energy intensity and per capita income has been ascertained. The surge in per-capita income gives birth to the rise of energy intensity in the beginning however, the energy intensity begins to fall down when the per-capita income reaches at the specific level. And, that specific level has been invested as US $ 5499.07 in this study. The main contribution of this study is to ascertain the threshold level of income and support the inverted U-shaped linkage between energy intensity and per capita income. The per capita income has been discovered as one of the main determinant of energy efficiency in the conclusion of this study that helps out the policy engineers in launching the policy instruments causing increase in per-capita income; but, that increase in per- capita income will only be saluted if the energy intensity falls down at higher levels of per-capita income. The study concludes that the rise of industrialization gives boost to the energy intensity but it does not mean that it put the promotion of industrialization on the back burner. Instead, it advises the policy designers to take steps to decrease the destructive offshoots of industrialization on energy intensity.