Combining indicators of energy consumption and CO2 emissions: a cross-country comparison

When countries are compared in terms of their carbon emission intensities, carbon emissions are normally considered as a function of either energy consumption, GDP, population or any other suitable variable. These can be termed as partial indicators as they consider emissions as a function of only one variable. Simultaneous consideration of more variables affecting carbon emissions is relatively complex. In this paper, several variables are simultaneously considered in comparing carbon emissions of countries using a new mathematical programming methodology, called the Data Envelopment Analysis. We have illustrated the use of the methodology with four variables representing CO2 emissions, energy consumption and economic activity. The illustrative analysis shows that Luxembourg, Norway, Sudan, Switzerland and Tanzania have been considered the most efficient countries, followed by India and Nigeria. Central European countries such as Poland, Romania, the Czech Republic, and South Africa are the least efficient.