Justifying the incorporation of the materials balance principle into frontier-based eco-efficiency models

Frontier-based models are an alternative to traditional eco-efficiency ratio indicators. This paper considers two different types, environmentally adjusted production efficiency models and frontier eco-efficiency models, and tries to find justification for incorporating the materials balance principle (MBP) in them. Similar importance is attached to the economic and environmental outcomes of a production process. Like economic outcomes can be derived from inputs and outputs and respective prices, some cases allow for deriving environmental outcomes from the production function with the MBP. After an overview of attempts to incorporate environmental issues in production efficiency models and some reflections why MBP has been neglected in environmental economics and production efficiency analysis, the paper gives basic principles to incorporate the MBP in conventional production efficiency methods and shows how this adjustment leads to a more diversified diagnosis of eco-efficiency. Finally, potentialities and bottlenecks are discussed. Exploiting the MBP in production efficiency and eco-efficiency analysis will facilitate more pro-active eco-efficiency research.