Eco-efficiency trends in the UK steel and aluminum industries: differences between resource efficiency and resource productivity

Measures of eco-efficiency—broadly understood as "getting more from less"—often include an economic and an environmental variable. The latter is often seen as the more problematic variable, particularly when used in relation to impacts of public concern. But an analysis of resource and value trends in the U.K. steel and aluminum industries over the last 30 yr showed that there are significant problems associated with using economic variables in measures of eco-efficiency at the sectoral level. The research found that the U.K. steel and aluminum industries have improved the effectiveness with which they use natural resources, but that this has been accompanied by a decline in the economic output (value added) per unit of material or energy consumed. These seemingly contradictory results can be explained by the fall in the price of metals in real terms, and by the competitive pressures that necessitate the cutting of production costs and indirectly lead to a fall in the measure of economic output of the relevant industry. The research also suggests a logical terminology to bring consistency and coherence to the broad field of eco-efficiency indicators, with an important distinction made between measures that examine the value output per unit of physical input, and measures that examine the physical output per unit of physical input. Both these types of indicators are important, as they highlight different aspects of eco-efficiency.