1. Nominal efficiency

Efficiency was first considered in industrial circles in the 90s, after a WBCSD(*) commission had taken it on board. The emergence of this concept on the economic scene corresponds to the recognition of a new dimension of technology, since until now it was only a question of yield, i.e. the ratio between the resources mobilized and those incorporated in an object. But this calculation was made all other things being equal. This was without taking into account environmental effects, and without any idea of measurement.