Problem formulation and quantification in energy analysis

Conflicting practices in energy analyses are discussed in relation to the problem formulation. The information needed to choose between known production alternatives in order to save energy is not a thermodynamic description of energy flows. What is necessary to know, is how much the considered alternatives require of scarce resources, and what their yield of goods and services is and the possible environmental effects. Aggregation of inputs and aggregation of outputs in physical units, in particular energy units, are discussed. Aggregates which can not be given a rational interpretation in relation to energy conservation must be rejected. Inputs which cannot be aggregated, however, may still be important substitutes. Land for example can be used to produce biomass to substitute for fossil fuel and fuel can be used to substitute for land and labour. For substitution, it is important to consider energy use in relation to the use of other scarce resources. In order to choose between alternatives, we have to attach values to the physical consequences of actions. Values depend on the degree of scarcity of different resources, of how important we consider satisfaction of various demands and of our concern for future generations. These values vary through space and time, and between individuals and interest groups.