Direct and indirect effects of heterogeneous technical change on metal consumption intensity: Evidence from G7 and BRICS countries

Abstract

To improve metal utilization efficiency, the effects of technical change cannot be ignored. However, existing researches often ignored the heterogeneous effects of different types of technical change on metal consumption intensity. Taking the G7 and BRICS countries as samples, this article first identifies the direct effects of heterogeneous technical change on the consumption intensity of iron ores, copper and aluminum from magnitude of technical change (MTC) and biased technical change (BTC). Then, industrial structure and metal consumption are introduced as mediating variables to identify the indirect effects of heterogeneous technical change. The results show the following: (1) there is a lag in the effect of TC on reducing metal consumption intensity and its effect on iron ore consumption intensity is the most significant. Reduction of iron ore consumption intensity mainly depends on MTC, whereas the reduction of copper and aluminum consumption intensity mainly depends on BTC. (2) The effects of heterogeneous technical change on metal consumption intensity in BRICS countries were consistent with the overall samples, while the effects of BTC on the intensity of copper and aluminum are positive in G7 countries. (3) Three types of technical change can reduce metal consumption intensity through the rationalization and advancement of industrial structure, and their effects are heterogeneous for different metals. (4) TC and BTC cannot reduce metal consumption intensity through reducing metal consumption due to a rebound effect, whereas MTC can significantly reduce iron ore consumption intensity by reducing iron ore consumption.