Decomposition Analysis of Aggregate Energy Intensity Changes in Tunisia over the Period 1980-2007

The aim of this paper is to investigate the main factors that have contributed to the decline in aggregate energy intensity of the Tunisian economy, during the period 1980-2007. Using the Logarithmic Mean Division Index (LMDI) decomposition method, we decompose the total changes in energy intensity into inter-fuel substitution effects, technological effects, and structural effects. The decomposition analysis is carried out at two levels of sectoral disaggregation (3 sectors and 13 sub-sectors) and uses three energy sources: petroleum, natural gas, and electricity. Our results show that the main contributor to the decline in energy intensity of the Tunisian economy throughout the period studied is the technological effect. This result was confirmed when we decomposed the energy intensity changes in the industrial and service sectors. On the other hand, the inter-fuel substitution effect contributed to increasing energy intensity, but without affecting its general downward trend. Finally, for the structural effects, we observed a significant mutual effect of cancellation at sector and sub-sector levels.